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HomeMy WebLinkAbout1.00 General Application Materials 1800 Larimer Street Denver, CO 80202 February 14, 2024 Via email to ghartmann@garfield-county.com and pberry@garfield-county.com Glenn Hartmann, Director of Community Development Philip Berry, Senior Planner 108 8th Street, Suite 401 Glenwood Springs, Colorado 81601 RE: Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild Project— Pre-Application for Temporary Use Permit Dear Mr. Hartmann and Mr. Berry: Public Service Company of Colorado (PSCo), a Colorado corporation conducting business as Xcel Energy, is requesting a Temporary Use Permit (TUP) for a temporary construction area (TCA) within Garfield County (County) that is a part of the Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild (Project). Approximately 0.20 mile of the existing line occurs within County jurisdiction, with the remaining length within City of Glenwood Springs jurisdiction. A Garfield County Location & Extent (L&E) Permit (LAEA- 10-21-8869) has been approved for the 0.20-mile portion of the line that traverses County jurisdiction. A City of Glenwood Springs L&E permit and 1041 permit (Planning File #45- 23) have been approved for the approximate 2-mile portion of the line that traverses City jurisdiction. Project representatives met with County staff at the Pre-Application Conference for the TUP, held on December 12, 2023. The enclosed TUP application was prepared per the requirements outlined in the Pre-Application Conference Summary and Sections 4-120 and 4-203 of the Garfield County Land Use and Development Code. This request for a TUP only applies to the TCA within County jurisdiction. We look forward to working with you during the ongoing permit process. Please feel free contact me by telephone at (303) 285-6533 or email at jennifer.l.chester@xcelenergy.com, or our permitting consultant, Amy Sherman, Tetra Tech, by telephone at (719) 755-3170 or email at amy.sherman@tetratech.com. Sincerely, Jennifer Chester Xcel Energy Siting and Land Rights, Manager 1800 Larimer St Denver, CO, 80202 Community Development Department 108 8th Street, Suite 401 Glenwood Springs, CO 81601 (970) 945-8212 www.garfield-county.com LAND USE CHANGE PERMIT APPLICATION FORM TYPE OF APPLICATION Administrative Review Development in 100-Year Floodplain Limited Impact Review Development in 100-Year Floodplain Variance Major Impact Review Code Text Amendment Amendments to an Approved LUCP LIR MIR SUP Rezoning Zone District PUD PUD Amendment Minor Temporary Housing Facility Administrative Interpretation Vacation of a County Road/Public ROW Appeal of Administrative Interpretation Location and Extent Review Areas and Activities of State Interest Comprehensive Plan Amendment Accommodation Pursuant to Fair Housing Act Pipeline Development Variance Time Extension (also check type of original application) INVOLVED PARTIES Owner/Applicant Name: ________________________________________________ Phone: (______)_________________ Mailing Address: ______________________________________________________________________ City: _______________________________________ State: _______ Zip Code: ____________________ E-mail:_______________________________________________________________________________ Representative (Authorization Required) Name: ________________________________________________ Phone: (______)_________________ Mailing Address: ______________________________________________________________________ City: _______________________________________ State: _______ Zip Code: ____________________ E-mail:_______________________________________________________________________________ PROJECT NAME AND LOCATION Project Name: _____________________________________________________________________________________ Assessor’s Parcel Number: 218505400065 Physical/Street Address: ________________________________________________________________ Legal Description: ______________________________________________________________________ _____________________________________________________________________________________ Zone District: ___________________________________ Property Size (acres): __________________ PROJECT DESCRIPTION REQUEST FOR WAIVERS Submission Requirements The Applicant requesting a Waiver of Submission Requirements per Section 4-202. List: Section: ______________________________ Section: _________________________________ Section: ______________________________ Section: _________________________________ Waiver of Standards The Applicant is requesting a Waiver of Standards per Section 4-118. List: Section: ______________________________ Section: _________________________________ Section: ______________________________ Section: _________________________________ I have read the statements above and have provided the required attached information which is correct and accurate to the best of my knowledge. ______________________________________________________ __________________________ Signature of Property Owner or Authorized Representative, Title Date OFFICIAL USE ONLY File Number: __ __ __ __ - __ __ __ __ Fee Paid: $_____________________________ Existing Use: ____________________________________________________________________________________ Proposed Use (From Use Table 3-403): ____________________________________________________ Description of Project: __________________________________________________________________ 1.The Decision you are appealing. 2.The date the Decision was sent as specified in the notice (date mailed). 3.The nature of the decision and the specified ground for appeal. Please cite specific code sections and/or relevant documentation to support your request. 4.The appropriate appeal fee of $250.00. 5.Please note a completed Appeal Application and fees must be received within 30 calendar days of the date of the final written Administrative Interpretation. For Appeal of Administrative Interpretation please include: Glenwood Springs to Mitchell Creek Electric Transmission Line Rebuild Temporary Use Application February 2024 Presented to: Garfield County Community Development 108 8th Street, Suite 401 Glenwood Springs, CO 81601 Submitted by: Xcel Energy 1800 Larimer St, Suite 400 Denver, CO 80202 This page intentionally left blank. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild Glenwood Springs to Mitchell Creek Electric Transmission Line Rebuild Garfield County Temporary Use Application Submittal Temporary Use Submittal Requirements Requirement per Pre-Application Conference Summary Location in Permit Application General Application Materials Application Form Behind Cover Letter Section 2a Payment of Fees Section 2b Signed Payment Agreement Form Section 2c Appendix A A narrative describing the request and related information Section 2d Proof of Ownership Section 2e Appendix B-1 A recorded Statement of Authority Section 2f Appendix C A Letter of Permission Section 2g Appendix B-2 Names and mailing addresses of property owners within 200 ft. of the subject property Section 2h Appendix D A copy of the Preapplication Summary Section 2i Appendix E Vicinity Map Section 3 Figure 1 Description of Applicant Section 4 Temporary Use Description Section 5 Copy of all previous approvals Section 6 Impact Analysis Section 7 Compliance with Section 7-1301 Temporary Use Section 8 Compliance with Article 7 Standards Section 9 Waiver request from submittal requirements according to 4-202, specifically addressing the review criteria for each waiver request Section 10 Waivers from Article 7 Standards Section 11 Requirement per Section 4-120 of the Garfield County Land Use and Development Code Location in Permit Application Fees Section 2b Section 12 Appendix A Description of Applicant Section 4 Section 12 Location and Extent Review Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild Applicant that is not the Property Owner Section 4a Section 12 Appendix B Temporary Use Description Section 5 Section 12 Copy of all Previous Related Approval Documents Section 6 Section 12 Impact Analysis and Proposed Mitigation Section 7 Table 3 Section 12 Requirement per Section 4-203 of the Garfield County Land Use and Development Code Location in Permit Application Professional Qualifications Section 13a General Application Materials Section 13b Application Form Behind Cover Letter Section 2a Section 13b Ownership Section 2e Section 13b Appendix B-1 Adjacent Property Owners and Mineral Owners and Lessees Section 2h Section 13b Appendix D Fees Section 2b Section 13b Appendix A Project Description Section 2d Section 5 Section 13b General Requirements for Maps and Plans Section 13b Combination of Map and Plan Requirements Section 13b Applications for Major Projects Section 13b Vicinity Map Section 3 Section 13c Figure 1 Site Plan Section 13d Appendix F Grading and Drainage Plan Section 13e Appendix G Landscape Plan Section 13f Impact Analysis Section 7 Table 3 Section 13g Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild Rezoning Justification Report Section 13h Statement of Appeal Section 13i Development Agreement Section 13j Improvements Agreement Section 13k Traffic Study Section 5.d Section 7.e Table 3 Section 8.d Section 13l Water Supply and Distribution Plan Section 7.d Table 3 Section 13m Wastewater Management and System Plan Section 7.d Table 3 Section 13n Floodplain Analysis Section 7.d Section 8.c Table 3 Section 13o Location and Extent Review Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 1 Contents Page 1. Introduction ........................................................................................................................................... 5 1a. Regulatory Framework .................................................................................................................. 5 1b. State of Colorado .......................................................................................................................... 5 1c. Garfield County ............................................................................................................................. 5 1d. City of Glenwood Springs .............................................................................................................. 5 2. General Application Materials .............................................................................................................. 7 2a. Application Form ........................................................................................................................... 7 2b. Payment of Fees ........................................................................................................................... 7 2c. Signed Payment Agreement Form ................................................................................................ 7 2d. Narrative Describing the Request and Related Information ........................................................... 7 2e. Proof of Ownership ........................................................................................................................ 7 2f. Statement of Authority ................................................................................................................... 7 2g. Letter of Permission ...................................................................................................................... 7 2h. Names and Mailing Addresses of Property Owners within 200 ft. of the subject property ............. 8 2i. Copy of the Pre-Application Summary .......................................................................................... 8 3. Vicinity Map ........................................................................................................................................... 8 4. Description of the Applicant ................................................................................................................ 8 4a. Applicant that is not the Property Owner ....................................................................................... 8 5. Temporary Use Description ................................................................................................................. 8 5a. Project Context .............................................................................................................................. 8 5b. Temporary Construction Area ....................................................................................................... 9 5c. Construction Methods ................................................................................................................... 9 5d. Construction Duration and Timing ............................................................................................... 10 6. Copy of all Previous Approvals ......................................................................................................... 11 7. Impact Analysis and Proposed Mitigation ........................................................................................ 11 7a. Air Quality .................................................................................................................................... 11 7b. Noise ........................................................................................................................................... 11 7c. Light ............................................................................................................................................ 12 7d. Water, Stormwater, Wastewater .................................................................................................. 12 7e. Other Impacts .............................................................................................................................. 12 7.e.1 Roads and Traffic ........................................................................................................ 12 7.e.2 Public Rights-of-Way ................................................................................................... 13 7.e.3 Public Parks ................................................................................................................. 13 7.e.4 FAA Required Evacuations .......................................................................................... 13 8. Compliance with Section 7-1301 Temporary Use ............................................................................. 14 Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 2 8a. The applicant, or a member of the applicant’s household, has not applied for a permit for the same or similar use more than twice within the prior twelve (12) month period. (7- 1301. A.)...................................................................................................................................... 14 8b. The use does not result in any negative long-term impact to adjacent properties, public infrastructure, or existing environmental conditions. (7-1301.B.) ................................................. 14 8.b.1 Adjacent Properties ..................................................................................................... 14 8.b.2 Public Infrastructure ..................................................................................................... 14 8.b.3 Environmental Conditions ............................................................................................ 14 8c. The use minimized any significant, adverse short-term impact to adjacent properties, public infrastructure, or existing environmental conditions. (7-1301.C.) ...................................... 15 8d. Pedestrian and vehicular traffic associated with the use are not hazardous or conflict with the existing and anticipated traffic in the neighborhood. ...................................................... 17 8e. Utility, drainage, and other necessary facilities to serve the proposed use will be provided. ..................................................................................................................................... 17 8f. The Temporary Use location protects the public health, safety, welfare, environment, infrastructure, and wildlife resources of Garfield County ............................................................. 17 8.f.1 Public Health, Safety and Welfare ................................................................................... 17 8.f.2 Environment..................................................................................................................... 18 8.f.3 Infrastructure.................................................................................................................... 18 8.f.4 Wildlife Resources ........................................................................................................... 18 9. Compliance with Article 7 Standards ................................................................................................ 21 10. Waiver Request from Submittal Requirements According to 4-202 ............................................... 27 11. Waivers from Article 7 Standards ...................................................................................................... 27 12. Requirements Per Section 4-120 ....................................................................................................... 27 13. Requirements Per Section 4-203 ....................................................................................................... 27 13a. Professional Qualifications (4-203.A) .......................................................................................... 27 13b. General Application Materials (4-203.B) ...................................................................................... 28 13c. Vicinity Map (4-203.C) ................................................................................................................. 29 13d. Site Plan (4-203.D) ...................................................................................................................... 29 13e. Grading and Drainage Plan (4-203.E) ......................................................................................... 29 13f. Landscape Plan (4-203.F) ........................................................................................................... 29 13g. Impact Analysis (4-203.G) ........................................................................................................... 30 13h. Rezoning Justification Report (4-203.H) ...................................................................................... 30 13i. Statement of Appeal (4-203.I) ..................................................................................................... 30 13j. Development Agreement (4-203.J) ............................................................................................. 30 13k. Improvements Agreement (4-203.K) ........................................................................................... 30 13l. Traffic Study (4-203.L) ................................................................................................................. 30 13m. Water Supply and Distribution Plan (4-203.M) ............................................................................ 30 13n. Wastewater Management System Plan (4-203.N) ...................................................................... 30 13o. Floodplain Analysis (4-203.O) ..................................................................................................... 30 14. Bibliography ........................................................................................................................................ 31 Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 3 Appendices Appendix A: Payment Agreement Form Appendix B: Proof of Ownership and Landowner Authorization Appendix C: Statement of Authority Appendix D: Names and Addresses of Property Owners within 200 Feet of the Subject Property Appendix E: Pre-Application Summary Appendix F: Site Plan Appendix G: Drainage Memo Appendix H: Geotechnical Engineering Report Appendix I: Revegetation Plan Appendix J: CPW Correspondence Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 4 Tables Table 1: Land Use Permit Requirements and Applicability to Project ............................................................ 6 Table 2: Anticipated Project Schedule ......................................................................................................... 11 Table 3: Best Practices to Minimize Temporary Construction Impacts ........................................................ 15 Table 4: Compliance with Article 7 Standards ............................................................................................. 21 Table 5: Compliance with Section 4-120.B Submittal Requirements ........................................................... 27 Table 6: Professional Qualifications............................................................................................................. 28 Table 7: Compliance with Section 4-203.B Submittal Requirements ........................................................... 28 Figures Figure 1: Vicinity Map Figure 2: Water Resources Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 5 1. Introduction Public Service Company of Colorado (PSCo), a Colorado corporation conducting business as Xcel Energy, is requesting a Temporary Use Permit (TUP) for a temporary construction area (TCA) within Garfield County (County) that is a part of the Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild (Project). Xcel Energy is proposing to rebuild the existing 2.25-mile portion of 69-kilovolt (kV) transmission line in unincorporated Garfield County and the City of Glenwood Springs (City). The existing transmission line must be rebuilt because it has reached the end of its operational life. The rebuilt transmission line will be in the same alignment as the existing route that connects the existing Glenwood Springs Substation, located northeast of the Glenwood Hot Springs Resort, to the existing Mitchell Creek Substation, located northwest of the Glenwood Meadows shopping center (Figure 1). Approximately 0.20 mile of the existing line is located within County jurisdiction, with the remaining length within City jurisdiction (Figure 1). A Location and Extent (L&E) permit was approved by Garfield County on January 10, 2024 (LAEA-10-21-8869) for the portion of the Project located in Garfield County. This request for a TUP applies to the TCA within County jurisdiction (Figure 2). Project representatives met with County staff at the Pre-Application Conference for the TUP, held on December 12, 2023. This request for a TUP was prepared per the requirements outlined in the Pre-Application Conference Summary and Sections 4-120 and 4-203 of the Garfield County Land Use and Development Code. 1a. Regulatory Framework City code and state statues apply to the Project in addition to County TUP regulations. The regulatory requirements are described in the following sections and Table 1. All required land use, environmental, and construction permits will be obtained prior to the start of and maintained during construction. 1b. State of Colorado Colorado Statutory Provisions apply to the Project, including a notice and consultation with local permitting jurisdictions. 1c. Garfield County The Garfield County L&E Permit (LAEA-10-21-8869) has been approved for the 0.20-mile portion of the line that traverses County jurisdiction just west of Highlands Drive. Transmission poles will be placed in four locations in unincorporated Garfield County (pole locations 133-136). 1d. City of Glenwood Springs The City of Glenwood Springs L&E permit and 1041 permit (Planning File #45-23) have been approved for the approximate 2-mile portion of the line that traverses City jurisdiction. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 6 Table 1: Land Use Permit Requirements and Applicability to Project1 Jurisdiction Title Trigger Statutory Reference Status State of Colorado Notification of Intention to Submit Permit Application for Major Electrical Facilities Filing permit application for location, construction, or improvement of major electrical or natural gas facilities. CRS 29-20-108 (4) (a) On October 22, 2020, Xcel Energy submitted a Notification of Intention to Submit Permit Application for Major Electrical Facilities with the Pre- Application Conference Request for the L&E Application City of Glenwood Springs L&E Permit Project proposed by a publicly owned utility City of Glenwood Springs Code of Ordinances 090.060.050(d) Xcel Energy received L&E permit approval from the City of Glenwood Springs on December 12, 2024 (Planning File #45-23). City of Glenwood Springs 1041 Permit Site selection of major facilities of any public utility to be located within the City of Glenwood Springs City of Glenwood Springs Code of Ordinances 070.080.030 Xcel Energy received 1041 permit approval from the City of Glenwood Springs on January 4, 2024 (Planning File #45- 23). Garfield County L&E Review Project proposed by a public utility, unless the public utility project is a designated activity of a State interest Garfield County Land Use and Development Code, Article 4-111, (1) (D) Xcel Energy received L&E permit approval from Garfield County on January 10, 2024 (LAEA- 10-21-8869). Garfield County Temporary Use Permit Proposed activities such as storage yards for construction activities; temporary batch plants; or helicopter landing to deliver construction materials. Garfield County Land Use and Development Code, Article 4-120 Xcel Energy is complying through this permit application and subsequent process for approval. 1 Xcel Energy’s understanding is that the County Code requires copies of all relevant permits for which the TCA will be used. Thus, despite being located outside of the County’s jurisdiction, permits from the City of Glenwood Springs are included in this table for completeness. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 7 2. General Application Materials 2a. Application Form The completed application form is included as part of this permit package, located behind the cover letter. 2b. Payment of Fees The $250.00 planning review fee for the TUP Application will be paid upon receipt of an invoice. 2c. Signed Payment Agreement Form The Payment Agreement Form is included as Appendix A. 2d. Narrative Describing the Request and Related Information Xcel Energy is requesting a TUP for the TCA within County jurisdiction to support the construction of the Project. The TCA will be used as a temporary construction yard, a helicopter fly yard and for material staging, construction access, and conductor wire pulling. This TCA will be used to stage construction equipment and materials including temporary construction trailers, cranes, and steel poles. This TCA is also necessary for construction crew parking, materials setup, and stringing the conductor wire. This TCA will not require grading, but the area will be mowed prior to use. At the end of the construction phase, all equipment will be removed from the TCA and the TCA will be restored generally consistent with preconstruction conditions, as provided for in the easement agreement. Rutted and disturbed areas will be revegetated. Additional information regarding the TCA use is included in Section 5. 2e. Proof of Ownership Xcel Energy has secured an easement agreement with the property owner, Jozefa Fit. A copy of this agreement is provided in Appendix B-1. 2f. Statement of Authority A Statement of Authority is provided as Appendix C. 2g. Letter of Permission Xcel Energy has secured an easement agreement with the property owner, Jozefa Fit. A copy of this agreement is provided in Appendix B-1. As explained in the letter included in Appendix B-2, since Xcel Energy holds an easement for the TCA, it holds a recognized property interest in the land on which the TCA is proposed and does not require consent of the surface landowner to submit the TUP application. Thus, no letter of consent signed by the landowner is included in this TUP application. See Appendix B for additional detail. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 8 2h. Names and Mailing Addresses of Property Owners within 200 ft. of the subject property The names and addresses of property owners within 200 feet of the parcel owned by Jozefa Fit (the “Fit Parcel”) have been provided in Appendix D along with a map depicting the properties. 2i. Copy of the Pre-Application Summary A copy of the Pre-Application Summary is provided in Appendix E. 3. Vicinity Map A Vicinity Map is included as Figure 1. 4. Description of the Applicant Xcel Energy is a major U.S. regulated electric and natural gas delivery company that serves approximately 3.7 million electric and 2.1 million natural gas customers across parts of eight Midwestern and Western states. PSCo is a Colorado corporation conducting business as Xcel Energy. 4a. Applicant that is not the Property Owner Xcel Energy holds permanent and temporary easements for the Fit Parcel, for the transmission line and the TCA respectively. This TUP application submittal addresses only the TCA on the Fit Parcel to be used during construction of the Project. A redacted signed agreement with the landowner is provided in Appendix B. 5. Temporary Use Description This TUP application is for the use of only the TCA within Garfield County. The remaining portions of the Project within Garfield County were approved under L&E Permit #LAEA-10-21-8869. 5a. Project Context Xcel Energy is proposing to rebuild a section of an existing 69-kV transmission line in City jurisdiction and unincorporated County jurisdiction to replace aging infrastructure and to ensure continued delivery of economic, safe and reliable electric service to customers in western Colorado. The existing transmission line was originally built in the 1940s, and a portion was rebuilt in the 1960s. The transmission line segment between the existing Glenwood Springs and Mitchell Creek substations needs to be rebuilt because it has reached the end of its operational life. The location of the corridor for the existing line was established more than 70 years ago. The line will be rebuilt to current industry design standards that include additional measures to reduce wildfire risk and use of the existing transmission line corridor and access routes, where possible. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 9 Approximately 0.20 mile of the existing transmission line occurs within County jurisdiction, with the remaining length within the City jurisdiction (Planning File #45-23). The TCA is located northwest of the intersection of Donegan Road and Highlands Drive, located near pole locations 133 and 134, within unincorporated Garfield County. The TCA will be used during the construction and installation of Project components within both County and City jurisdiction (Figure 1). The TCA is located directly adjacent to the existing transmission line along a flat, elevated mesa that is set back from major roads and dense development, making it an ideal location for a helicopter fly yard. Being directly adjacent to the existing transmission line will enable the helicopters to fly directly along the transmission line easement, minimizing the number of homes and businesses that will be impacted by helicopter activity. 5b. Temporary Construction Area The TCA will be used as a temporary construction yard, a helicopter fly yard, and for material staging, construction access and conductor wire pulling. This TCA will be used to store and stage construction equipment and materials, including temporary construction trailers, skid steers, crew haul trucks, work trucks and plastic barrels for storage of smaller materials. Portable toilets for crews and dumpsters for construction waste will be provided at the TCA for use during construction. This TCA is also necessary for materials setup and stringing the conductor wire. Equipment to support pole replacement activities including digger trucks, air compressors, cranes and bucket trucks may be parked at the TCA. Soil stockpiles generated from pole excavations will be temporarily stored at the TCA before being hauled off- site. Equipment to support helicopter operations including a helicopter, crew truck, helicopter fuel truck and water truck/trailer will be located at the TCA. A designated helicopter landing zone is shown in the TCA Site Plan, provided as Appendix F. Equipment to support conductor wire pulling activities, including the following, will be located at the TCA: truck/trailer mounted pulling equipment, tractor trailer wire boat, truck with tensioner, trailered hydraulic tensioner, fiber tensioner and a V-Groove Conductor pull with a trailer. Pole and material delivery to the TCA will originate from the helicopter fly yard in Glenwood Springs. The truck delivery route will follow Traver Trail south to Highway 6, Highway 6 west to Donegan Road, Donegan Road north to Highland Drive, then Highland Drive north to the access drive. The TCA does not require grading and will only require mowing and/or mulching. A Site Plan showing the layout of the TCA is provided in Appendix F. At the end of the construction phase, all equipment will be removed from the TCA. The TCA in Garfield County will be restored by revegetating rutted or disturbed areas generally consistent with preconstruction conditions, and as required by the easement agreement. Materials will be delivered by semi-trucks or flatbed trucks. Access to the TCA will be from a private driveway for which Xcel Energy has obtained a permit located west of Highlands Drive and north of Donegan Road. During construction, the access road will be used for vehicle, equipment and material ingress and egress to the TCA. 5c. Construction Methods Project construction work is expected to occur in phases which generally include the following: construction access and vegetation clearing, equipment mobilization and material delivery, foundation construction, pole placement, conductor stringing, and land restoration. Set-up of the TCA will need to be Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 10 conducted prior to construction. The access road will allow construction crews and vehicles to access transmission line pole locations and the TCA. After the preparation work is complete, work on the transmission poles will begin. Two poles will be located adjacent to the TCA. The new pole foundations will consist of concrete reinforced with steel that can range in diameter and depth based upon the subsurface conditions. Once construction crews drill the hole for the new pole, the foundation will be installed, and the hole will be backfilled. The four transmission pole locations (133-136) in Garfield County will be placed using a helicopter. Helicopter installation involves assembling the transmission poles in the material staging area then transporting each pole by helicopter to its installation location to be lowered into place. Helicopter installation enables access to areas that are difficult for construction vehicles to traverse, minimizes construction impacts such as erosion, and expedites construction. This type of installation improves construction efficiency and avoids ground disturbance in areas of steep terrain. Due to the nature of helicopter installation and Federal Aviation Administration (FAA) safety requirements, residences and businesses will be required to evacuate if they are within a certain distance of a helicopter that is carrying a suspended load. Xcel Energy and the construction contractor will coordinate with the FAA during helicopter operations and obtain all required permits, including a Congested Area Plan (CAP). Xcel Energy and the construction contractor will provide residents with prior notice where evacuations are required. The TCA will also be used as a pull-site. Once all the transmission poles are in place, the conductor wire is strung using a temporary pulley system attached to the insulators. TCAs are required at specific angles to ensure the conductor wire is pulled in line with the poles, remaining in alignment. The existing poles will be removed by crane, or in areas of steep terrain, by helicopter and the Project will be energized. After construction, the work areas and ROW will be restored. The Project will not require water (other than water for construction), or wastewater treatment. Water for construction will be trucked in from a permitted source. 5d. Construction Duration and Timing Construction is expected to begin in Spring 2024, pending permit approvals. Construction and restoration activities are expected to be completed and the Project will be put into service by Summer 2024. See Table 2 below for the anticipated Project schedule. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 11 Table 2: Anticipated Project Schedule Timeline Activity Spring 2024 Permanent Improvements Spring 2024 Vegetation Management Spring 2024/Summer 2024 Construction of Transmission Poles Spring 2024/Summer 2024 Removal of Existing Poles Summer 2024 In Service Summer 2024/Fall 2024 Restoration 6. Copy of all Previous Approvals A summary and status of all relevant permitting documents is included in Table 1. Copies of approved permits can be provided to Garfield County upon request. 7. Impact Analysis and Proposed Mitigation The TCA within Garfield County is located on a parcel that is zoned Rural and has an existing transmission line through the area. Temporary uses, such as the TCA, are allowed in any zone district pursuant to Section 3-401.D of the Land Use and Development Code. The access road is an existing private driveway for which Xcel Energy has obtained a permit. Potential impacts would be temporary and limited to the construction phase. 7a. Air Quality Short-term effects related to construction are anticipated from a temporary increase in construction vehicles, which may increase fumes and fugitive dust from construction equipment exhaust (fumes) and from clearing and preparing areas for construction (dust). The short-term effects are not expected to cause a public nuisance. Water trucks will be utilized during construction activities to suppress dust from vehicles and equipment as necessary. 7b. Noise Construction-related noise will result in temporary short-term increases in noise near the TCA. Short-term noise will result during construction, helicopter operations, foundation installation, and assembly and erection of the transmission line poles. Short-term noise is anticipated from construction equipment such as auguring machines, helicopters, heavy machinery and trucks. While one 12-hour shift per day is anticipated during construction, helicopter use will be limited. Helicopter operations out of the TCA in Garfield County are anticipated to occur for a total of 4 days over the construction period with a duration Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 12 of 12 hours per day. Construction vehicles and equipment will be maintained in proper operating condition and equipped with manufacturer’s standard noise control devices (e.g., mufflers or engine enclosures). 7c. Light It is anticipated that one 12-hour shift per day (Monday through Saturday) will be worked during transmission line construction. Construction would be during daylight hours, early morning to early evening, thus no lighting plan is currently anticipated to be necessary. If additional hours are anticipated for shift work, temporary lighting may be required to ensure safe construction activities at night. Temporary lighting would be a combination of light plants and truck-mounted lights and only used as needed. Glare is not expected from construction including from vehicles, equipment, or materials. 7d. Water, Stormwater, Wastewater The TCA has been sited to avoid water resources and will avoid impacts to wetlands, other waters of the U.S. (WOTUS) and regulated floodplains (Figure 2). The access road will utilize an existing private driveway for which Xcel Energy has obtained a permit; minor grading is required where the existing private road meets Highlands Drive to accommodate construction equipment. Impacts to water resources are not anticipated to result from the use of the TCA or from the minor grading work near Highlands Drive. Best Management Practices (BMPs) will be utilized to meet stormwater, grading, and erosion control requirements. Construction contractors will work with the County to obtain and follow all related construction permits. Road improvements are not expected within County jurisdiction. If road improvements are needed, Xcel Energy will acquire any necessary grading, stormwater, and erosion control permits and comply with permit requirements. Xcel Energy will acquire the necessary access easements where access routes traverse private property. Prior to construction, a Stormwater Management Plan (SWMP) will be developed, and a Storm Water Permit for Construction Activities will be obtained from the Colorado Department of Public Health and Environment (CDPHE). Xcel Energy will comply with permit requirements, Garfield County standards, and construction protocols to ensure that the use of the TCA does not violate water quality standards. Xcel Energy can provide copies of the stormwater permits to the County, as necessary, prior to the start of construction. A permanent water supply will not be required for activities at the TCA, and no impacts to existing water rights are anticipated. Water to be used during construction will be obtained from a permitted source. Construction activities at the TCA will not create any wastewater nor will the TCA have any facilities requiring wastewater treatment. Portable temporary bathrooms will be on site during the construction period and will be serviced on a regular basis. 7e. Other Impacts 7.e.1 Roads and Traffic Utilization of the TCA in Garfield County will involve the use of Highlands Drive and a private road leading to other homes in the surrounding area. Traffic to the TCA will be limited to work crew vehicles, construction equipment, and equipment delivery vehicles. It is not anticipated that construction equipment Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 13 or labor transportation will have a significant impact on traffic volumes or flow on local roadways or state/county highways. Any increases in traffic will be short-term in nature and limited to the construction time period near the TCAs and transmission pole locations. Helicopter operations out of the TCA in Garfield County are anticipated to occur for a total of 4 days over the construction period with a duration of 12 hours per day. During helicopter operations out of the TCA in Garfield County, it is anticipated that the helicopter will make between 1 and 8 trips per day to pole installation locations. When helicopters are carrying suspended loads and need to fly over a private or county road or highway, construction crews will temporarily pause traffic, per FAA requirements. County Road 130/Donegan Road is anticipated to be affected by temporary road closures when the helicopter passes overhead, carrying loads to poles 141 through 140; these impacts are anticipated to last approximately 4 days. A lane closure with flaggers is anticipated during work on poles 141 and 142; this closure is anticipated to last approximately 8 days. County Road 164/Midland Ave is anticipated to be affected by lane closures with flaggers during construction work on poles 145 through 147; this closure is anticipated to last approximately 14 days. Traffic stops will occur when the helicopter passes overhead with a suspended load; traffic stops are anticipated to last between 5 to 15 minutes depending on the specific work being performed. Breaks will occur during this duration to allow traffic to clear. Construction updates and schedules will be discussed with Garfield County as details are determined. 7.e.2 Public Rights-of-Way Public ROW will not be impacted as part of the TCA use. Traffic impacts from helicopter activities are discussed in Section 7.e.1. 7.e.3 Public Parks The TCA is not located near any public parks and will not cause impacts. 7.e.4 FAA Required Evacuations Due to the nature of helicopter installation and FAA safety requirements, residences and businesses will be required to temporarily evacuate if they are within a certain distance of a helicopter that is carrying a suspended load for the duration of time that the load is passing overhead. Xcel Energy has applied for and will acquire a CAP from the FAA prior to construction. Xcel Energy will also coordinate with the FAA during helicopter operations. Xcel Energy and the construction contractor will provide residents with prior notice if evacuation is required. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 14 8. Compliance with Section 7-1301 Temporary Use 8a. The applicant, or a member of the applicant’s household, has not applied for a permit for the same or similar use more than twice within the prior twelve (12) month period. (7-1301. A.) Xcel Energy nor its contractors, consultants or other associated persons have previously applied for a TUP for the TCA located in Garfield County for the Project. 8b. The use does not result in any negative long-term impact to adjacent properties, public infrastructure, or existing environmental conditions. (7- 1301.B.) 8.b.1 Adjacent Properties The TCA use will not result in any negative long-term impacts to adjacent properties because the TCA will be restored and returned to the original use upon completion of construction. Impacts will be limited to short-term impacts associated with construction, as described in Section 7. This TUP request is part of a larger project to replace aging electric infrastructure of the Glenwood to Mitchell Creek 69-kV transmission line. The Project will benefit adjacent properties by mitigating wildfire risk through rebuilding the existing aging infrastructure. 8.b.2 Public Infrastructure Local government services, transportation infrastructure, educational facilities, housing, water (other than trucked-in water for construction), sewage and wastewater treatment, public transportation, existing businesses, and social services are adequate to support the TCA use due to the small size of the construction crew and temporary nature of the construction activities. Given the relatively small size of the crews needed for construction of the Project, no impacts to emergency health care facilities or law enforcement services are anticipated. In Garfield County, one private driveway will be utilized to access the TCA during Project construction. While minor grading is required where the private road meets Highlands Drive, no road improvements are anticipated. Xcel Energy has engaged in landowner negotiations where the access road to the TCA traverses private property and will address any associated impact mitigation measures. 8.b.3 Environmental Conditions The TCA use will not result in any negative long-term impacts because the TCA will be restored and returned to the original use. It is not anticipated that the Project will result in new, permanent, adverse impacts. The TCA within Garfield County is zoned Rural and has an existing transmission line through the area. Potential impacts would be temporary and limited to the construction phase. Mowing will be required in the TCA, and Xcel Energy will revegetate the area after construction is complete. Potential impacts to environmental conditions are addressed in Section 7 and 8.f. of this TUP application. BMPs to minimize temporary construction-related impacts are included in Table 3. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 15 8c. The use minimized any significant, adverse short-term impact to adjacent properties, public infrastructure, or existing environmental conditions. (7- 1301.C.) Short-term impacts are expected to occur during construction and use of the TCA. A summary of proposed BMPs is included in Table 3. Table 3: Best Practices to Minimize Temporary Construction Impacts Resource Description of BMPs Air Quality Water trucks will be utilized during construction activities to suppress dust from vehicles and equipment as necessary. Biological Resources The TCA use will avoid or minimize impacts to habitat as practicable. Impacts to most vegetation will be temporary and limited to the TCA. The TCA will be cleared of tall vegetation and mowed, though the extent of vegetation removal for construction will be limited. Measures will be implemented to minimize the spread of noxious weeds. The Project will adhere to BMPs and erosion control measures, and the area will be revegetated and managed for noxious weeds. To avoid or minimize potential impacts to migratory birds and raptors, including eagles, Xcel Energy will conduct tree/vegetation clearing during the nonbreeding season for birds (September 1 – April 15) if feasible. If vegetation clearing cannot occur during the nonbreeding season, vegetation clearance surveys, raptor nest surveys, and burrowing owl surveys may be conducted per USFWS and CPW guidance to identify avian nesting activity and determine appropriate avoidance buffers (CPW 2020, CPW 2021) or monitor active nest sites until determined to be inactive. Cultural Resources No cultural resources have been identified in the TCA. The access road to the TCA follows an existing road for which Xcel Energy has obtained a permit, thereby minimizing impacts to cultural resources. Land Use The TCA use will be located adjacent to the existing transmission line to be rebuilt. The land is zoned Rural and, during construction, uses within the TCA will be limited to construction activities. After construction, the TCA will be restored and returned to the pre-construction use. Where residential and/or business evacuations are needed per FAA requirements, Xcel Energy and the construction contractor will provide residents with prior notice and coordinate with the County, as needed. Xcel Energy and the construction contractor will coordinate with the FAA during helicopter operations and obtain all required permits. Noise Construction vehicles and equipment will be maintained in proper operating condition and equipped with manufacturer’s standard noise control devices (e.g., mufflers or engine enclosures). Natural Hazards Xcel Energy conducted a geotechnical study along the transmission line alignment to assess soil conditions and design the foundations accordingly (Appendix H). One bore location was located at the TCA in Garfield County. No significant natural hazards have been identified in this area. Professional engineers will guide construction and do not foresee any risks in this area. In the rare event of a fire emergency, Xcel Energy will likely be aware of an issue before the general public or emergency responders. Nevertheless, the public is encouraged to contact Xcel Energy’s emergency number: 800-895-1999 with any concerns or in case of an emergency.. Each construction vehicle will be equipped with fire mitigation tools, shovels, a pick axe, portable water cans and fire extinguishers. Additionally, a water truck will be located at the TCA. Xcel Energy will coordinate closely with the local fire department and first responders and consult with them to discuss any concerns within their response area. Xcel Energy offers free online safety training to fire departments and first responders that is based on national standards through its Responding to Utility Emergencies Program. Socioeconomic Given the relatively small size of the crews needed for construction and the temporary nature of the construction activities, no impacts to availability of public resources and services are anticipated. During construction, revenue may moderately increase for some local businesses, such as restaurants, gas stations, grocery stores, and hotels as well as other local businesses due to spending by Xcel Energy’s contractors or employees. Soils and Geology During construction, Xcel Energy’s contractor will minimize any soils impacts by strictly adhering to a CDPHE- regulated SWMP and will institute and maintain erosion and sediment control BMPs designed to protect soils and prevent erosion. In areas that are difficult for construction vehicles to traverse, helicopter installation will be Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 16 Resource Description of BMPs used to minimize potential erosion impacts in areas of steep terrain or limited accessibility. Xcel Energy conducted a geotechnical study along the transmission line alignment to assess soil conditions and design the foundations accordingly (Appendix H). Toxic and Hazardous Substances Materials used during construction and operation will be used and disposed of in compliance with all applicable federal, state, and local regulations. Construction, operation, and maintenance activities will comply with applicable federal, state, and local laws and regulations regarding the use of hazardous substances. Construction activities will be performed by methods that prevent entrance or accidental spillage of solid matter, contaminants, debris, and other pollutants and wastes into flowing streams or dry watercourses, lakes, and underground water sources. Activities will follow BMPs for the management of wastes to avoid and minimize effects from potential spills or other releases to the environment. Transportation When helicopters are carrying suspended loads and need to fly over a private or county road or highway, construction crews will temporarily pause traffic, per FAA requirements. County Road 130/Donegan Road is anticipated to be affected by temporary road closures when the helicopter passes overhead, carrying loads to poles 141 through 140; these impacts are anticipated to last approximately 4 days. A lane closure with flaggers is anticipated during work on poles 141 and 142; this closure is anticipated to last approximately 8 days. County Road 164/Midland Ave is anticipated to be affected by lane closures with flaggers during construction work on poles 145 through 147; this closure is anticipated to last approximately 14 days. Traffic stops will occur when the helicopter passes overhead with a suspended load; traffic stops are anticipated to last between 5 to 15 minutes depending on the specific work being performed. Breaks will occur during this duration to allow traffic to clear. Construction updates and schedules will be discussed with the County as needed as details are determined. Vegetation The TCA use will avoid or minimize impacts to vegetation generally as practicable. Impacts to most vegetation will be temporary and limited to the TCA. The TCA will be cleared of tall vegetation and mowed ahead of construction, though vegetation removal will be limited. Measures will be implemented to minimize the spread of noxious weeds in the ROW. The Project will adhere to BMPs and erosion control measures outlined in the SWMP. Once construction has been completed, the TCA will be restored in a manner generally similar to its condition prior to construction and as may be provided for in private agreements. This work may include fence repair, rut removal, decompaction, tilling, seeding, and stabilization measures. All areas not needed for ongoing operations and maintenance will be reclaimed (re-seeded compatible with Xcel Energy’s vegetation management standards) as soon as practicable following construction. A Revegetation Plan is provided in Appendix I. Visual Resources Construction vehicles, equipment, and materials will be temporarily visible in the TCA along with increased activity related to construction. Once construction is complete, the TCA will be restored in a manner generally similar to its condition prior to construction Waste Enclosed containment will be provided for trash disposal. Construction waste, including trash and litter, garbage, other solid waste, petroleum products, and other potentially hazardous materials, will be removed and taken to a disposal facility authorized to accept such materials. Construction activities will be performed with methods that prevent entrance or accidental spillage of solid matter, contaminants, debris, and other pollutants and wastes into flowing streams or dry watercourses, lakes, and underground water sources. All activities will follow BMPs for the management of wastes to avoid and minimize effects from potential spills or other releases to the environment. The use of the TCA will not create any wastewater nor have any facilities requiring wastewater treatment. Portable temporary bathrooms that will be serviced on a regular basis will be on site during the construction period. Water Resources The TCA was sited to avoid water resources and will avoid impacts to wetlands, other WOTUS and regulated floodplains (Figure 2). Construction contractors will work with the appropriate jurisdictions to obtain and follow all related construction permits. To avoid potential indirect impacts from construction-related erosion and sediment movement during construction, the Project will adhere to BMPs outlined in the SWMP, which will include erosion control and revegetation measures. Construction activities will be performed in a manner that prevent entrance or accidental spillage of solid matter, contaminants, debris, and other pollutants and wastes into flowing streams or dry watercourses, lakes, and underground water sources. All activities will follow BMPs for the management of wastes to avoid and minimize effects from potential spills or other releases to the environment. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 17 Resource Description of BMPs The Project will not impact the quantity or quality of water flowing off of the site. Xcel Energy will comply with permit application requirements, County Standards, and construction protocols to ensure that the use of the TCA does not violate water quality standards. Prior to construction, a Storm Water Permit for Construction Activities will be obtained from CDPHE and a SWMP will be developed. 8d. Pedestrian and vehicular traffic associated with the use are not hazardous or conflict with the existing and anticipated traffic in the neighborhood. Utilization of the TCA in Garfield County will involve the use of Highlands Drive and a private road leading to other homes in the surrounding area. Traffic to the TCA will be limited to work crew vehicles, construction equipment, and equipment delivery vehicles. It is not anticipated that construction equipment or labor transportation will have a significant impact on traffic volumes or flow on local roadways or driveways. Any increases in traffic will be short-term in nature and limited to the construction time period near the TCAs and transmission pole locations. Section 7.e.1 of this application discusses the anticipated traffic impacts associated with helicopter activities. 8e. Utility, drainage, and other necessary facilities to serve the proposed use will be provided. No new or upgraded utilities, drainage or facilities are anticipated to be needed to serve the TCA. Construction will not create runoff in excess of previous site levels and will not change existing topography or adversely affect drainage. There will be no alteration in the pattern or intensity of surface drainage as a result of construction. To avoid potential indirect impacts from construction-related erosion and sediment movement during construction, the Project will adhere to BMPs outlined in the SWMP, which will include erosion control and revegetation measures. 8f. The Temporary Use location protects the public health, safety, welfare, environment, infrastructure, and wildlife resources of Garfield County 8.f.1 Public Health, Safety and Welfare It is not anticipated that the TCA use will have any impacts to public health, safety or welfare. In order to protect public safety, Xcel Energy will follow FAA evacuation requirements during helicopter activities. Helicopter installation will be used in areas with steep terrain and involves assembling the transmission poles in the material staging area then transporting the poles by helicopter to installation locations to be lowered into place. Helicopter installation enables access to areas that are difficult for construction vehicles to traverse, minimizes construction impacts such as erosion, and expedites construction. This type of installation improves construction efficiency and helps protect the environment in areas of steep terrain. Due to the nature of helicopter installation and FAA safety requirements, residents and businesses will be required to temporarily evacuate when a helicopter carrying a load is within a certain distance outlined in the CAP. Xcel Energy and the construction contractor will coordinate with the FAA during helicopter operations and obtain all required permits. Xcel Energy and the construction contractor will coordinate with the City on the evacuation plan and provide residents with prior notice if evacuation is required. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 18 8.f.2 Environment The Impact Analysis is discussed in Section 7 and BMPs are discussed in detail in Section 8.C and Table 3. 8.f.3 Infrastructure The TCA use is part of a larger project to improve the electrical infrastructure in City jurisdiction and a portion of County jurisdiction. Xcel Energy is proposing to rebuild a section of an existing 69-kV transmission line to replace aging infrastructure and to ensure continued delivery of economic, safe and reliable electric service to customers in the County and western Colorado. The existing transmission line was originally built in the 1940s, and a portion was rebuilt in the 1960s. The transmission line segment between the existing Glenwood Springs and Mitchell Creek substations needs to be rebuilt because it has reached the end of its operational life. The location of the corridor for the existing line was established more than 70 years ago. The line will be rebuilt to current industry design standards that include additional measures to reduce wildfire risk and use of the existing transmission line corridor and access routes, where possible. The use of the TCA creates no additional demand for transportation infrastructure, educational facilities, housing, water (other than trucked-in water for construction), sewage or wastewater treatment, or public transportation. Existing businesses and social services are adequate to support the use of the TCA due to the small size of the construction crew and temporary nature of the construction activities. Given the relatively small size of the crews needed for construction of the Project, no impacts to emergency health care facilities or law enforcement services are anticipated. Section 7.e.1 of this application discusses the anticipated traffic impacts during construction. 8.f.4 Wildlife Resources The TCA use will avoid or minimize impacts to habitat as practicable. Impacts to most vegetation will be temporary and limited to the TCA. The TCA will be cleared of tall vegetation and mowed prior to the start of construction activities, however, vegetation removal will be limited. Measures will be implemented to minimize the spread of noxious weeds. Construction work will adhere to BMPs and erosion control measures outlined in the SWMP. Xcel Energy requested Environmental Reviews from CPW and USFWS on March 22, 2022 but did not receive a response from either agency. Xcel Energy followed up with CPW, requesting another Environmental Review on August 11, 2023. CPW reported that there are “limited adverse impacts to wildlife resources” (Appendix J). Xcel Energy will continue to coordinate with CPW and USFWS through permitting, construction, and operation of the Project as needed to ensure compliance with all applicable federal and state regulations. To avoid or minimize potential impacts to migratory birds and raptors, including eagles, Xcel Energy will conduct tree/vegetation clearing during the nonbreeding season for birds (September 1 – April 15) if feasible. If vegetation clearing cannot occur during the nonbreeding season, vegetation clearance surveys, raptor nest surveys, and burrowing owl surveys may be conducted per USFWS and CPW Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 19 guidance to identify avian nesting activity and determine appropriate avoidance buffers (CPW 2020, CPW 2021) or monitor active nest sites until determined to be inactive. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 20 This page intentionally left blank. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 21 9. Compliance with Article 7 Standards Table 4: Compliance with Article 7 Standards Article 7 Standard TUP Compliance Division 1: General Approval Standards 7-101. Zone District Use Regulations The TCA is located on a parcel that is zoned Rural. Temporary uses, such as the TCA, are allowed in any zone district pursuant to Section 3-401.D of the Land Use and Development Code. Article 3 of the Garfield County Land Use and Development Code states that the Rural Zone District is “intended to protect the existing character of the area from uncontrolled and unmitigated residential, commercial and industrial use. The zone district provides for the use of natural resources, recreational development, rural residential, and other uses” (Garfield County 2023). The TCA will be located adjacent to the existing transmission line to be rebuilt. During construction, uses within the TCA will be limited to construction activities. After construction, the TCA will be restored and returned to the pre-construction use. Article 3, Section 3-401 (D) states that “temporary uses may be allowed in any zone district in accordance with the procedures of Section 4-120” (Garfield County 2023). Application Submittal Requirements outlined in Section 4-120 of the Garfield County Land Use and Development Code are addressed in Sections 2b, 4, 5, 6 and 7 of this application. 7-102. Comprehensive Plan and Intergovernmental Agreements Garfield County Comprehensive Plan 2030 outlines key policies and strategies in four chapters that support the County’s vision for 2030 (Garfield County 2020a). The Vision for Garfield County is dedicated to managing and directing growth to dedicated Urban Growth Areas and other areas that can accommodate growth cost effectively, in order to create thriving communities while promoting a diverse, sustainable and healthy economy, protecting wildlife, maintain or improving the quality of our natural environment, and preserving the county’s rural and western heritage. (Garfield County 2020a). This TCA use is in conformance with this vision as it supports the rebuild of an existing transmission line that provides electric service to meet existing and future needs. Chapter 2 Future Land Use Chapter 2 of the Comprehensive Plan outlines five major themes to support future land use in Garfield County. One theme focuses on development in Urban Growth Areas (UGAs), preferred locations for municipality expansion. According to the Garfield County Future Land Use Map, Glenwood Springs has two UGAs near the Project (Garfield County 2020b). Each community is expected to extend services and infrastructure to development in the UGA that substantially complies with their plan for the UGA (landowners and the respective municipality are strongly encouraged to enter into pre-annexation agreements that provide commitments with respect to extensions of service and infrastructure, densities, etc.).The TCA use supports maintaining the City’s viability as a town center by supporting the rebuild of an existing transmission line that will continue to provide reliable electric service to the area. (Garfield County 2020a). Chapter 3, Section 4—Economics, Employment and Tourism Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 22 The vision of Chapter 3 Section 4 of the Garfield County Comprehensive Plan 2030, emphasizes economic development in and around County population centers. The Colorado State Demography Office (CSDO) projects that from 2017 to 2040 the County’s population will increase by an average of 1,287 persons per year. This is a 55% increase from the annual average between 2001 and 2017. The CSDO projections highlight important planning considerations concerning where and how to accommodate the future growth, and how to ensure that public infrastructure and services will accommodate this growth (Garfield County 2020a). The TCA use supports the rebuild of an existing transmission line, strengthening the existing energy infrastructure and ensuring continued reliable energy service to Glenwood Springs. The Project ultimately supports the growth of industrial, commercial, and residential uses in the surrounding areas. Policy 3—Visual, Traffic and Environmental Impacts The strategy for Policy 3 is to ensure that impacts from industrial development (including mineral extraction) are adequately mitigated to minimize negative impacts on tourism, quality of life resources and community character. Sections 7 and 8 of this permit application detail the anticipated temporary visual, traffic, and environmental impacts and BMPs associated with the TCA use. Policy 4—Economic Resiliency and Diversity Policy 4 aims to strengthen the County’s economic resiliency for employment and income generation by continuing to diversity the economy (Garfield County 2020a). Several strategies associated with this policy focus on encouraging growth and expansion of existing industries within the County. The TCA use will support the rebuild of an existing transmission line to revitalize and strengthen the electric infrastructure within the County. Section 8—Natural Resources The vision of Chapter 3 Section 8 of the Garfield County Comprehensive Plan 2030 emphasizes the need to protect and/or mitigate the impacts to biological resources. The TCA is located adjacent to the existing transmission line alignment within the County, reducing the impacts to surrounding land use and resources. Table 3 of this permit application details the anticipated temporary impacts mitigation related to the environment and wildlife resources. 7-103. Compatibility The TCA will be located adjacent to the existing transmission line to be rebuilt. Land uses directly surrounding the TCA include the existing transmission line and rural residential. Commercial development is located just south and southeast of the TCA. Uses within the TCA will be limited to construction activities. Anticipated temporary impacts of activities at the TCA and associated BMPs are discussed in Sections 7 and 8 of this permit application. After construction, the TCA will be restored and returned to the pre-construction use. 7-104. Source Of Water A permanent water supply will not be required for activities at the TCA as the activities are temporary in nature. Water to be used during construction will be obtained from a permitted source. 7-105. Central Water Distribution And Wastewater Systems A permanent water supply will not be required for activities at the TCA as the activities are temporary in nature. Water to be used during construction will be obtained from a permitted source. Construction activities at the TCA will not create any wastewater nor will the TCA have any facilities requiring wastewater treatment. Portable temporary bathrooms will be on site during the construction period and will be serviced on a regular basis. 7-106. Public Utilities The TCA activities will not require connection to any public utilities. The TCA use is part of a larger Public Utility project to improve the electrical infrastructure in City jurisdiction and a portion of County jurisdiction. The rebuilt transmission line will adhere to current industry design standards that include additional measures to reduce wildfire risk. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 23 7-107. Access And Roadways No new road or accesses off public ROW are proposed as a part of the TCA. Sections 7 and 8 of this application detail the anticipated impacts and BMPs related to roads and traffic. 7-108. Use Of Land Subject To Natural Hazards The TCA is not located in an area with identified Natural and Geologic Hazards. Xcel Energy conducted a geotechnical study along the transmission line alignment to assess soil conditions and design the foundations accordingly (Appendix H). One bore location was located at the TCA in Garfield County. No significant natural hazards have been identified in this area. Professional engineers will guide construction and do not foresee any risks in this area. Additionally, the activities within the TCA will be temporary and related to construction of the Project; once construction has been completed, the TCA will be restored in a manner generally similar to its condition prior to construction and as may be provided for in private agreements. 7-109. Fire Protection In the rare event of a fire emergency, Xcel Energy will likely be aware of an issue before the general public or emergency responders. Nevertheless, the public is encouraged to contact Xcel Energy’s emergency number: 800-895-1999 with any concerns or in case of an emergency. Each construction vehicle will be equipped with fire mitigation tools, shovels, a pick axe, portable water cans and fire extinguishers. Additionally, a water truck will be located at the TCA. Xcel Energy will coordinate closely with the local fire department and first responders and consult with them to discuss any concerns within their response area. Xcel Energy offers free online safety training to fire departments and first responders that is based on national standards through its Responding to Utility Emergencies Program. Division 2: General Resource Protection Standards 7-201. Agricultural Lands It is not anticipated that activities at the TCA will adversely affect agricultural operations, nor is any division or development of land proposed as a part of those activities. Land uses surrounding the TCA include the existing transmission line and rural residential. Uses within the TCA will be limited to construction activities. Anticipated temporary impacts of activities at the TCA and associated BMPs are discussed in Sections 7 and 8 of this permit application. After construction, the TCA will be restored and returned to the pre-construction use. No permanent roads are proposed as part of the TCA; Section 7a and Table 3 outline the anticipated dust impacts and BMPs during construction. No ditches are proposed as part of the TCA, nor are any impacts to existing ditches anticipated. 7-202. Wildlife Habitat Areas Sections 7 and 8 of this application detail the anticipated impacts and BMPs related to wildlife and wildlife habitat areas. Xcel Energy’s coordination with CPW on the Project is included as Appendix J. The Project’s Revegetation Plan is included as Appendix I. 7-203. Protection Of Waterbodies Sections 7 and 8 of this application detail the anticipated impacts and BMPs related to water resources. 7-204. Drainage And Erosion Sections 7 and 8 of this application detail the anticipated impacts and BMPs related to drainage and erosion. Prior to construction, a SWMP will be developed, and a Storm Water Permit for Construction Activities will be obtained from the CDPHE. Xcel Energy will comply with permit requirements, Garfield County standards, and construction protocols to ensure that the use of the TCA does not violate water quality standards. Xcel Energy can provide copies of the stormwater permits to the County, as necessary, prior to the start of construction. 7-205. Environmental Quality Sections 7 and 8 of this application detail the anticipated impacts and BMPs related to air and water quality. 7-206. Wildfire Hazards The TCA use supports the rebuild of an existing transmission line to replace aging infrastructure and to ensure continued delivery of economic, safe and reliable electric service to customers in western Colorado. The existing transmission line was originally built in the 1940s, and a portion was rebuilt in the 1960s. The transmission line segment between the existing Glenwood Springs and Mitchell Creek substations needs to be rebuilt because it has reached the end of its operational life. The line will be rebuilt to current industry design standards that include additional measures to reduce wildfire risk. During Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 24 construction, each construction vehicle will be equipped with fire mitigation tools, shovels, a pick axe, portable water cans and fire extinguishers. Additionally, a water truck will be located at the TCA. Xcel Energy developed a Wildfire Mitigation Plan in 2020 that identified eight 69kV transmission lines to be replaced by 2025 as a part of its Major Transmission Line Rebuild Plan (Xcel Energy 2020). This Project is within a portion of one of the eight transmission lines identified for replacement. This Project will mitigate the wildfire risk by rebuilding the existing aging infrastructure. 7-207. Natural And Geologic Hazards The TCA is not located in an area with identified Natural and Geologic Hazards. Xcel Energy conducted a geotechnical study along the transmission line alignment to assess soil conditions and design the foundations accordingly (Appendix H). One bore location was located at the TCA in Garfield County. No significant natural hazards have been identified in this area. Professional engineers will guide construction and do not foresee any risks in this area. Additionally, the activities within the TCA will be temporary and related to construction of the Project; once construction has been completed, the TCA will be restored in a manner generally similar to its condition prior to construction and as may be provided for in private agreements. 7-208. Reclamation This TCA will not require grading, but the area will be mowed prior to use. Surface impacts will be temporary and limited to the TCA. The TCA will be cleared of tall vegetation and mowed ahead of construction, though vegetation removal will be limited. Measures will be implemented to minimize the spread of noxious weeds in the ROW. The Project, including the use of the TCA, will adhere to BMPs and erosion control measures outlined in the SWMP. Once construction has been completed, the TCA will be restored in a manner generally similar to its condition prior to construction and as may be provided for in private agreements. This work may include fence repair, rut removal, decompaction, tilling, seeding, and stabilization measures. The TCA will be reclaimed (re-seeded compatible with Xcel Energy’s vegetation management standards) as soon as practicable following construction. A Revegetation Plan is provided in Appendix I. Xcel Energy will complete restoration activities within the duration of the TUP and will continue to coordinate with Garfield County regarding the level of acceptable vegetative cover. Division 3: Site Planning and Development Standards 7-301. Compatible Design The TCA does not feature any particular design components as it will be used as a temporary construction yard, a helicopter fly yard and for material staging, construction access, and conductor wire pulling. This TCA will be used to stage construction equipment and materials including temporary construction trailers, cranes, and steel poles. This TCA is also necessary for construction crew parking, materials setup, and stringing the conductor wire. Access to the TCA will be from a private driveway for which Xcel Energy has obtained a permit, located west of Highlands Drive and north of Donegan Road. Anticipated temporary impacts, including air, noise, and light impacts, are discussed in Section 7 and BMPs are discussed in Table 3. It is anticipated that one 12-hour shift per day (Monday through Saturday) will be worked during transmission line construction; however, additional hours may be required. Construction would be during daylight hours, early morning to early evening. 7-302. Off-Street Parking And Loading Standards No permanent parking or loading areas are proposed as a part of this TCA. This TCA will be used to stage construction equipment and materials including temporary construction trailers, cranes, and steel poles. This TCA is also necessary for construction crew parking, materials setup, and stringing the conductor wire. Construction crew parking and all other activities will be limited to the construction period. 7-303. Landscaping Standards The TCA use will avoid or minimize impacts to vegetation generally as practicable. Impacts to most vegetation will be temporary and limited to the TCA. The TCA will be cleared of tall vegetation and mowed ahead of construction, though vegetation removal will be limited. Measures will be implemented to minimize the spread of noxious weeds in the ROW. The Project will adhere to BMPs and erosion control measures outlined in the SWMP. Once construction has been completed, the TCA will be restored in a manner generally similar to its condition prior to construction and as may be provided for in private agreements. This work may include fence repair, rut removal, Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 25 decompaction, tilling, seeding, and stabilization measures. All areas not needed for ongoing operations and maintenance will be reclaimed (re-seeded compatible with Xcel Energy’s vegetation management standards) as soon as practicable following construction. A Landscaping Plan is not proposed as part of the TCA; however, a Revegetation Plan is provided in Appendix I. 7-304. Lighting Standards Anticipated impacts related to light are discussed in Section 7c of this application. A Lighting Plan is not proposed since construction activity is not anticipated to occur at night. 7-305. Snow Storage Standards A snow storage area is not proposed within the TCA. Given that the TCA is not paved, it will not be plowed in the event of snowfall. 7-306. Trail And Walkway Standards No trails or walkways are proposed as a part of the TCA. Division 13: Additional Standards for Temporary Uses 7-1301.A. The applicant, or a member of the applicant’s household, has not applied for a permit for the same or similar use more than twice within the prior twelve (12) month period. This Division 13 standard is addressed under Section 8a of this application. 7-1301.B. The use does not result in any negative long-term impact to adjacent properties, public infrastructure, or existing environmental conditions. This Division 13 standard is addressed under Section 8b of this application. 7-1301.C. The use minimized any significant, adverse short-term impact to adjacent properties, public infrastructure, or existing environmental conditions. This Division 13 standard is addressed under Section 8c of this application. 7-1301.D. Pedestrian and vehicular traffic associated with the use are not hazardous or conflict with the existing and anticipated traffic in the neighborhood. This Division 13 standard is addressed under Section 8d of this application. 7-1301.E. Utility, drainage, and other necessary facilities to serve the proposed use will be provided. This Division 13 standard is addressed under Section 8e of this application. 7-1301.F. The temporary use location protects the public health, safety, welfare, environment, infrastructure, and wildlife resources of Garfield County. This Division 13 standard is addressed under Section 8f of this application. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 26 This page intentionally left blank. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 27 10. Waiver Request from Submittal Requirements According to 4-202 Xcel Energy is not requesting any waivers from the submittal requirements outlined in Section 4-202. 11. Waivers from Article 7 Standards Xcel Energy is not requesting any waivers from the submittal requirements outlined in Section 4-202. 12. Requirements Per Section 4-120 The requirements detailed in Section 4-120.B are included in the table below along with locations in this permit application where these requirements are addressed. Table 5: Compliance with Section 4-120.B Submittal Requirements Section 4-120.B Application Section Reference 4-120.B.1. Fees This Section 4-120.B submittal requirement is addressed under Section 2.b of this application. 4-120.B.2. Description of Applicant This Section 4-120.B submittal requirement is addressed under Section 4 of this application. 4-120.B.2.a. Applicant that is not the Property Owner This Section 4-120.B submittal requirement is addressed under Section 4.a of this application. 4-120.B.3. Temporary Use Description This Section 4-120.B submittal requirement is addressed under Section 5 of this application. 4-120.B.4. Copy of all Previous Related Approval Documents This Section 4-120.B submittal requirement is addressed under Section 6 of this application. 4-120.B.5. Impact Analysis and Proposed Mitigation This Section 4-120.B submittal requirement is addressed under Section 7 of this application. 13. Requirements Per Section 4-203 13a. Professional Qualifications (4-203.A) The following table details the professional qualifications for preparation and certification of certain documents included in this permit application. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 28 Table 6: Professional Qualifications Document in Permit Application Name Qualifications HDR ENGINEERING Revegetation Plan Tara Rae Kent Sr. Environmental Scientist Brian Brown Civil Engineer – Project Manager 1670 Broadway, Suite 3400, Denver, CO 80202 Certified Ecologist, 15 years-experience in the environmental field with a focus on botany and wetlands including extensive field plant surveys and agency coordination. Senior Site Civil Project Manager with 28 years of experience in Colorado focused on site civil grading and drainage, erosion control and site revegetation. Site Plan Brian Brown Civil Engineer – Project Manager 1670 Broadway, Suite 3400, Denver, CO 80202 Senior Site Civil Engineer with 28 years of experience in Colorado with a focus on site grading, surface drainage, erosion control, and a background in geotechnical engineering. Drainage Memo Brian Brown Civil Engineer – Project Manager 1670 Broadway, Suite 3400, Denver, CO 80202 Senior Site Civil Engineer with 28 years of experience in Colorado with a focus on site grading, surface drainage, erosion control, and a background in geotechnical engineering. TERRACON CONSULTANTS Geotechnical Report Scott Myers, P.E. Regional Senior Consultant 10625 W. I-70 Frontage Rd. N., Suite 3, Wheat Ridge, CO 80033 Scott Myers is a geotechnical engineer with a professional engineering license in Colorado. 13b. General Application Materials (4-203.B) The requirements detailed in Section 4-203.B are included in the table below along with locations in this permit application where these requirements are addressed. Table 7: Compliance with Section 4-203.B Submittal Requirements Section 4-203.B Application Section Reference 4-203.B.1. Application Form This Section 4-203.B submittal requirement is addressed under Section 2.a of this application. 4-203.B.1.a. Authorized Representative This Section 4-203.B submittal requirement is addressed under Section 2.g of this application. 4-203.B.1.b. Applicant is Not the Sole Owner This Section 4-203.B submittal requirement is addressed under Section 2.e of this application. 4-203.B.1.c. Applicant is an Entity This Section 4-203.B submittal requirement is addressed under Section 2.f of this application. 4-203.B.2. Ownership This Section 4-203.B submittal requirement is addressed under Section 2.e of this application. 4-203.B.3. Adjacent Property Owners and Mineral Owners and Lessees The Section 4-203.B submittal requirement regarding adjacent property owners is addressed under Section 2.h of this application. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 29 With respect to mineral owners, written notification to mineral estate owners of the public hearing will not be provided for the Project. The state statute commonly known as “The Surface Development Notification Act” (CRS 24-65.5-101 et seq) provides that not less than 30 days before the date scheduled for the initial public hearing by a local government on an application for development, the applicant must send a notice of that hearing by certified mail to mineral estate owners (owners or lessees of the mineral estate under the property which is the subject of the application). Pursuant to the Act, the definition of an “Application for Development” covers a wide range of surface development land use approvals, but certain named development activities are specifically exempt from that definition. One exemption includes applications with respect to electric lines such as the Project. Thus, due to the nature and scope of the Project, the transmission line rebuild Project is exempt from the statutory mineral estate owner mailing notification requirements. Accordingly, based on this statutory exemption, Xcel Energy will not be including a list of owners of the mineral estate under the property which is subject to the TUP application. See Appendix B-2 for additional information. 4-203.B.4. Fees This Section 4-203.B submittal requirement is addressed under Section 2.b of this application. 4-203.B.5. Project Description This Section 4-203.B submittal requirement is addressed under Section 2.d and Section 5 of this application. 4-203.B.6. General Requirements for Maps and Plans Xcel Energy acknowledges the general requirements for maps and plans. 4-203.B.7. Combination of Map and Plan Requirements Not applicable. 4-203.B.8. Applications for Major Projects Not applicable. 13c. Vicinity Map (4-203.C) This Section 4-203 submittal requirement is addressed under Section 3 of this application. 13d. Site Plan (4-203.D) A Site Plan is included in this permit application as Appendix F. 13e. Grading and Drainage Plan (4-203.E) A Grading Plan is not included in this application as grading is not proposed at the TCA. A Drainage Memo is included in this permit application as Appendix G. 13f. Landscape Plan (4-203.F) The TCA use will avoid or minimize impacts to vegetation generally as practicable. Impacts to most vegetation will be temporary and limited to the TCA. The TCA will be cleared of tall vegetation and mowed ahead of construction, though vegetation removal will be limited. Measures will be implemented to minimize the spread of noxious weeds in the ROW. The Project, including the use of the TCA, will adhere to BMPs and erosion control measures outlined in the SWMP. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 30 Once construction has been completed, the TCA will be restored in a manner generally similar to its condition prior to construction and as may be provided for in private agreements. This work may include fence repair, rut removal, decompaction, tilling, seeding, and stabilization measures. All areas not needed for ongoing operations and maintenance will be reclaimed (re-seeded compatible with Xcel Energy’s vegetation management standards) as soon as practicable following construction. A Landscaping Plan is not proposed as part of the TCA; however, a Revegetation Plan is provided in Appendix I. 13g. Impact Analysis (4-203.G) This Section 4-203 submittal requirement is addressed under Sections 7, 8 and 9 of this application. 13h. Rezoning Justification Report (4-203.H) Rezoning is not proposed as a part of the TCA and therefore this requirement is not applicable. 13i. Statement of Appeal (4-203.I) Xcel Energy acknowledges the Statement of Appeal process. 13j. Development Agreement (4-203.J) Xcel Energy acknowledges the process for a Development Agreement, should one be required. 13k. Improvements Agreement (4-203.K) No public improvements are proposed as a part of the TCA; therefore, this requirement is not applicable. 13l. Traffic Study (4-203.L) This Section 4-203 submittal requirement is addressed under Sections 5.d, 7.e and 8.d of this application. 13m. Water Supply and Distribution Plan (4-203.M) This Section 4-203 submittal requirement is addressed under Section 7.d of this application. 13n. Wastewater Management System Plan (4-203.N) This Section 4-203 submittal requirement is addressed under Section 7.d of this application. 13o. Floodplain Analysis (4-203.O) This Section 4-203 submittal requirement is addressed under Sections 7.d and 8.c of this application. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 31 14. Bibliography CPW (Colorado Parks and Wildlife). 2021. Colorado Parks and Wildlife Recommendations to Avoid and Minimize Impacts to Wildlife from Land Use Development in Colorado. Available online at: https://cpw.state.co.us/Documents/Conservation-Resources/Energy-Mining/CPW_HPH-Map- Layers.pdf. Accessed January 2024. ———. 2020. Recommended Buffer Zones and Seasonal Restrictions for Colorado Raptors. Available online at: https://cpw.state.co.us/Documents/WildlifeSpecies/LivingWithWildlife/Raptor-Buffer- Guidelines.pdf. Accessed January 2024. Garfield County. 2023. Land Use and Development Code. Available online at: https://www.garfield- county.com/community-development/filesgcco/sites/12/Complete-Land-Use-and-Development-Code- 1.pdf. Accessed January 2024. ———. 2020a. Comprehensive Plan 2030. Available online at: https://www.garfield- county.com/community-development/filesgcco/sites/12/Garfield-County-Comprehensive-Plan-2030-2020- Update.pdf. Accessed January 2024. ———. 2020b. Garfield County Comprehensive Plan—Future Land Use 2030. Available online at: https://data-garfieldcolorado.opendata.arcgis.com/app/3fb7922108e34a2fb267272e7cb99198. Accessed January 2024. Xcel Energy. 2020. Wildfire Mitigation Plan. Available online at: https://www.dora.state.co.us/pls/efi/efi_p2_v2_demo.show_document?p_dms_document_id=931117&p_s ession_id=. Accessed January 2024. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild 32 This page intentionally left blank. Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild Figures Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. Temporary Construction Area Mitchell Creek Substation Glenwood Springs Substation GARFIELD COUNTY City of Glenwood Springs 6 82 70 Pa t h : Z : \ P r o j e c t s \ D E N \ 6 5 5 8 _ C O _ G l e n w o o d _ M i t c h e l l C r e e k \ G I S \ P r o j e c ts \ G a r f i e l d C o _ T e m p U s e _ P e r m i t \ G a r f i e l d C o _ T e m p U s e _ P e r m i t . a p r x R e v i s e d : 1 / 2 3 / 2 0 2 4 Figure 1: Vicinity Map 0 10.5 Miles I Scale is 1:48,000 when printed at 8.5" x 11" RIO BLANCO COUNTY GARFIELD COUNTY EAGLE COUNTY MESA COUNTY PITKIN COUNTY 70 Garfield County Jurisdiction Existing Electrical Infrastructure Substation Access Road Rebuild Route (60-foot ROW) Temporary Construction Area (1.4 acres) Glenwood Springs-Mitchell Creek Electric Transmission Line Rebuild Project NOT FOR CONSTRUCTION Project Features Existing Transmission Line Corridor Figure Prepared by: C. Aishman on 1/23/2024 Applicant Jennifer Chester Xcel Energy Siting and Land Rights, Manager 1800 Larimer St Denver, CO, 80202 Engineer Josh Peterson Xcel Energy Principal Transmission Line Engineer 1800 Larimer St Denver, CO, 80202 Garfield County Parcel 3-mile Buffer of Temporary Construction Area Glenwood Springs Golf Club GARFIELD COUNTY City of Glenwood Springs 6 HARVARD D R COL UM BIA C T CASTLE C T T R A V E R T R P R I N C E T O N C I SU N NY A C R E S R D GREE N W A Y D R HIG H L AN D S D R DEVEREUX R D DON EGA N RD MIDL A N D A V 70 Colorado R i v e r Pa t h : Z : \ P r o j e c t s \ D E N \ 6 5 5 8 _ C O _ G l e n w o o d _ M i t c h e l l C r e e k \ G I S \ P r o j e c ts \ G a r f i e l d C o _ T e m p U s e _ P e r m i t \ G a r f i e l d C o _ T e m p U s e _ P e r m i t . a p r x R e v i s e d : 1 / 2 3 / 2 0 2 4 Figure 2: Water Resources 0 500250 Feet I Scale is 1:5,000 when printed at 8.5" x 11" RIO BLANCO COUNTY GARFIELD COUNTY EAGLE COUNTY MESA COUNTY PITKIN COUNTY 70 Garfield County Jurisdiction Existing Electrical Infrastructure Access Road Rebuild Route (60-foot ROW) Temporary Construction Area (1.4 acres) Glenwood Springs-Mitchell Creek Electric Transmission Line Rebuild Project NOT FOR CONSTRUCTION Project Features Existing Transmission Line Corridor Figure Prepared by: C. Aishman on 1/23/2024 Applicant Jennifer Chester Xcel Energy Siting and Land Rights, Manager 1800 Larimer St Denver, CO, 80202 Engineer Josh Peterson Xcel Energy Principal Transmission Line Engineer 1800 Larimer St Denver, CO, 80202 Water Resources Well Perennial Stream/River Freshwater Emergent Wetland Freshwater Pond Wetland Riverine Wetland 100-year Floodplain 500-year Floodplain Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix A: Payment Agreement Form Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. PAYMENT AGREEMENT FORM GARFIELD COUNTY (“COUNTY”) and Property Owner (“APPLICANT”) ______ ____ ______________________________________________________________________ agree as follows: 1. The Applicant has submitted to the County an application for the following Project: __________________. 2. The Applicant understands and agrees that Garfield County Resolution No. 2014-60, as amended, establishes a fee schedule for each type application, and the guidelines for the administration of the fee structure. 3. The Applicant and the County agree that because of the size, nature or scope of the proposed project, it is not possible at this time to ascertain the full extent of the costs involved in processing the application. The Applicant agrees to make payment of the Base Fee, established for the Project, and to thereafter permit additional costs to be billed to the Applicant. The Applicant agrees to make additional payments upon notification by the County, when they are necessary, as costs are incurred. 4. The Base Fee shall be in addition to and exclusive of any cost for publication or cost of consulting service determined necessary by the Board of County Commissioners for the consideration of an application or additional County staff time or expense not covered by the Base Fee. If actual recorded costs exceed the initial Base Fee, the Applicant shall pay additional billings to the County to reimburse the County for the processing of the Project. The Applicant acknowledges that all billing shall be paid prior to the final consideration by the County of any Land Use Change or Division of Land. I hereby agree to pay all fees related to this application: Billing Contact Person:_____________________________________ Phone: (_____)___________________ Billing Contact Address: ___________________________________________________________________ City: ______________________________________________ State: _______ Zip Code: ________________ Billing Contact Email: _____________________________________________________________________ Printed Name of Person Authorized to Sign: ___________________________________________________ ______ ________________________________ (Signature) (Date) Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix B: Proof of Ownership and Landowner Authorization Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix B-1: Proof of Ownership Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. This page intentionally left blank. Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix B-2: Landowner Authorization Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. Michelle Berger Direct Dial: 303-839-3790 mberger@spencerfane.com SPENCER FANE LLP | 1700 LI NCOLN STREET, SUI TE 2000, DENVER, CO 80203 -4554 | 303.839. 3800 | FAX | spencerf ane.com February 12, 2024 VIA E-MAIL Ms. Kelly Cave Assistant County Attorney Garfield County 108 8th Street, Suite 219 Glenwood Springs, CO 81601 Re: Xcel Energy - Transmission Line 6584 Rebuild Project, Glenwood Springs to Mitchell Creek Segment (Project) - Application for Temporary Use Permit (TUP) - Clarification and Confirmation Related to Landowner Authorization and Mineral Owner Notification Dear Ms. Cave: I am writing to you on behalf of Xcel Energy regarding the above-captioned Project and related Temporary Use Permit (“TUP”) application submittal requirements. Specifically, and consistent with prior permitting practices with Garfield County (“County”), I am writing to clarify and confirm that (1) Xcel Energy has the land rights and authority to apply for the TUP without submitting a signed letter of consent from the surface fee landowner; and (2) because the Project is exempt from statutory mineral owner notification requirements, Xcel Energy will not be providing a list of mineral owners nor mailing notifications regarding the application to mineral owners. With respect to these two submittal requirements, as has been previously discussed with my colleague, Gil McNeish, and allowed for in previous land use applications, Xcel Energy’s approach and reasoning are as follows: 1. Sections 4-203.B.3.b and 4-120.B.2.a – signed easement in lieu of letter signed by landowner consenting to submission of the application. As you know, the Project includes the replacement and rebuild of one segment of an existing electric transmission line between Glenwood Springs and Rifle. As part of the rebuild Project, Xcel Energy requires a temporary construction area (“TCA”) for the storage of materials and equipment, as well as helicopter and other operations necessitated by the Project. Xcel Energy has obtained a temporary construction easement for the TCA. Because Xcel Energy has the easement for the TCA, it holds a recognized property interest in the land on which the development is proposed and does not require the consent of the surface fee landowner to submit the TUP application. Thus, no separate letter of consent signed by the landowner will be included in the TUP application. In relation to its County Location and Extent permit for the Project, Xcel Energy accepted, as a condition of approval, providing copies of the executed easements to the County prior to beginning construction on a particular parcel. Here, since Xcel Energy has already obtained the necessary easement for the TCA, a copy of the easement is included in Appendix B of the TUP application. Ms. Kelly Cave February 8, 2024 Page 2 2. Notification of mineral estate owners related to the Project site. Section 4-203.B.3.b states “If an application requires mailed notice, the application shall include . . . b. A list of mineral owners in the Subject Site.” Xcel Energy’s understanding is its TUP application will require mailed notice because the Director will be referring the application to the Board of County Commissioners for a public hearing and final decision. As Mr. McNeish and you have previously discussed, Xcel Energy is exempt from Colorado statutes requiring notification of surface development to mineral owners. As such, no list of mineral owners in the subject site is necessary. To recap Mr. McNeish’s previous correspondence and discussions with you regarding this issue, the state statute commonly known as “The Surface Development Notification Act” (CRS 24-65.5-101 et seq) provides that not less than 30 days before the date scheduled for the initial public hearing by a local government on an application for development, the applicant must send a notice of that hearing by certified mail to mineral estate owners (owners or lessees of the mineral estate under the property which is the subject of the application). Pursuant to the Act, the definition of an “Application for Development” covers a wide range of surface development land use approvals, but certain named development activities are specifically exempt from that definition. One exemption includes applications “with respect to electric lines” such as Xcel Energy’s TUP application. Thus, due to the nature and scope of the Project, the TCA is exempt from the statutory mineral estate owner mailing notification requirements, so no list of mineral owners is necessary under the Garfield County Land Use and Development Code. Based on the foregoing, Xcel Energy will not be including a separate signed letter of authorization from the surface owner of the subject property or a list of owners of the mineral estate under the property which is subject to the TUP application. Consistent with prior practices, we wanted to clarify the reasoning for this approach to avoid having the application deemed incomplete upon initial submission. Please contact me if you have any questions. Very truly yours, SPENCER FANE LLP Michelle L. Berger cc: Julie Stencel – Xcel Energy (via email) Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix C: Statement of Authority Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. CERTIFICATE OF AUTHORITY I, Kristin Westlund, do hereby certify that I am the Assistant Secretary of Public Service Company of Colorado, a Colorado corporation (the “Company”), with an address of 1800 Larimer Street, Suite 400, Denver, Colorado 80202 and I do hereby further certify the authority of the Jennifer L. Chester, Manager, Siting and Land Rights, on behalf of the Company has authority to act on behalf of the Company to execute instruments conveying, encumbering or otherwise affecting title to real property and to bind the Company in matters of land use permitting. In witness whereof, the undersigned has hereunto set their hand as of the 14th day of February, 2024. Kristin Westlund Assistant Secretary Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix D: Names and Addresses of Property Owners within 200 Feet of the Subject Property Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. Appendix D: Names and Addresses of Property Owners within 200 Feet of the Subject Property PARCEL NUMBER OWNER CARE OF NAME OWNER ADDRESS OWNER CITY OWNER STATE OWNER ZIP PHYSICAL ADDRESS PHYSICAL CITY PHYSICAL STATE PHYSICAL ZIP 218505400085 MILA PROPERTIES LLC 476 JB COURT GLENWOOD SPRINGS, CO 81601 GLENWOOD SPRINGS CO 81601 1537 130 COUNTY RD GLENWOOD SPRINGS CO 81601 218505400122 ZANCANELLA, SHIRLEY L, FAMILY LIMITED PARTNERSHIP PO BOX 1908 GLENWOOD SPRINGS, CO 81602 GLENWOOD SPRINGS CO 81602 Not available GLENWOOD SPRINGS CO 81601 218505400065 FIT, JOZEFA 141 W 6TH STREET GLENWOOD SPRINGS, CO 81601 GLENWOOD SPRINGS CO 81601 1647 130 COUNTY RD GLENWOOD SPRINGS CO 81601 218505100064 GOBBLERS KNOB LLC PO BOX 1908 GLENWOOD SPRINGS, CO 81602 GLENWOOD SPRINGS CO 81602 1651 130 COUNTY RD GLENWOOD SPRINGS CO 81601 218505100123 ZANCANELLA, SHIRLEY L, FAMILY LIMITED PARTNERSHIP PO BOX 1908 GLENWOOD SPRINGS, CO 81602 GLENWOOD SPRINGS CO 81602 Not available GLENWOOD SPRINGS CO 81601 218505100103 ZANCANELLA, ANTHONY WILLIAM & NATALIE & THOMAS A & MICHELLE A 1649 COUNTY ROAD 130 GLENWOOD SPRINGS, CO 81601 GLENWOOD SPRINGS CO 81601 1649 130 COUNTY RD GLENWOOD SPRINGS CO 81601 218505400111 P & E PROPERTIES LLC 202 SUNNY ACRES ROAD GLENWOOD SPRINGS, CO 81601 GLENWOOD SPRINGS CO 81601 1539 DONEGAN RD GLENWOOD SPRINGS CO 81601 218505416002 STRIPP, KAREN L & MARK A 1653 DONEGAN ROAD GLENWOOD SPRINGS, CO 81601-2864 GLENWOOD SPRINGS CO 81601-2864 1653 DONEGAN RD GLENWOOD SPRINGS CO 81601 218505416001 STRIPP, KAREN L & MARK A 1653 DONEGAN ROAD GLENWOOD SPRINGS, CO 81601-2864 GLENWOOD SPRINGS CO 81601-2864 1653 DONEGAN RD GLENWOOD SPRINGS CO 81601 211935408025 GLENWOOD HIGHLANDS ESTATES HOMEOWNERS ASSOC PAM SZEDELYI 601 HIGHLANDS DRIVE GLENWOOD SPRINGS, CO 81601 GLENWOOD SPRINGS CO 81601 Not available GLENWOOD SPRINGS CO 81601 218505400110 GLENWOOD HIGHLANDS ESTATES HOMEOWNERS ASSOC PAM SZEDELYI 601 HIGHLANDS DRIVE GLENWOOD SPRINGS, CO 81601 GLENWOOD SPRINGS CO 81601 Not available GLENWOOD SPRINGS CO 81601 GARFIELD COUNTY City of Glenwood Springs 6 H A RVA R D D R C OLU MBI A C T HIG H L A N D S D R DO NE G A N R D 218505400085 MILA PROPERTIES LLC 218505400122 ZANCANELLA, SHIRLEY L, FAMILY LIMITED PARTNERSHIP 218505400065 FIT, JOZEFA 218505100064 GOBBLERS KNOB LLC 218505100123 ZANCANELLA, SHIRLEY L, FAMILY LIMITED PARTNERSHIP 218505100103 ZANCANELLA, ANTHONY WILLIAM & NATALIE & THOMAS A & MICHELLE A 218 5 0 5 4 0 0 1 1 1 P & E P R O P E R T I E S LLC 218 5 0 5 4 1 6 0 0 2 STR I P P , K A R E N L & M A R K A 218 5 0 5 4 1 6 0 0 1 STR I P P , K A R E N L & M A R K A 211 9 3 5 4 0 8 0 2 5 GLE N W O O D H I G H L A N D S EST A T E S H O M E O W N E R S A S S O C 218505400110 GLENWOOD HIGHLANDS ESTATES HOMEOWNERS ASSOC Pa t h : Z : \ P r o j e c t s \ D E N \ 6 5 5 8 _ C O _ G l e n w o o d _ M i t c h e l l C r e e k \ G I S \ P r o j e c ts \ G a r f i e l d C o _ T e m p U s e _ P e r m i t \ G a r f i e l d C o _ T e m p U s e _ P e r m i t . a p r x R e v i s e d : 1 / 3 1 / 2 0 2 4 Properties within 200 Feet of the Subject Property 0 300150 Feet I Scale is 1:3,100 when printed at 8.5" x 11" RIO BLANCO COUNTY GARFIELD COUNTY EAGLE COUNTY MESA COUNTY PITKIN COUNTY 70 Garfield County Jurisdiction Existing Electrical Infrastructure Access Road Rebuild Route (60-foot ROW) Temporary Construction Area (1.4 acres) Glenwood Springs-Mitchell Creek Electric Transmission Line Rebuild Project NOT FOR CONSTRUCTION Project Features Existing Transmission Line Corridor Figure Prepared by: C. Aishman on 1/31/2024 Applicant Jennifer Chester Xcel Energy Siting and Land Rights, Manager 1800 Larimer St Denver, CO, 80202 Engineer Josh Peterson Xcel Energy Principal Transmission Line Engineer 1800 Larimer St Denver, CO, 80202 Garfield County Parcel Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix E: Pre-Application Summary Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. 1 Community Development Department 108 8th Street, Suite 401 Glenwood Springs, CO 81601 (970) 945-8212 www.garfield-county.com PRE-APPLICATION CONFERENCE SUMMARY TAX PARCEL NUMBER: Multiple DATE: 12/15/2023 PROJECT: XCEL Temporary Use Laydown Yards and Helistops OWNERS: Multiple CONTACT/REPRESENTATIVE: Corey Miller, Brooke Hines, Jen Chester, Erica Powell, Braleigh Jay, Melinda Schulze, Sara Crook, Jennifer Harris, Julie Stencel, Michelle Burger, Jose Castro, Brad McCloud, Evan Singleton PRACTICAL LOCATION: prefer address TYPE OF APPLICATION: Temporary Use for Laydown Yards and Helistops ZONING: Mostly Rural COMPREHENSIVE PLAN: Multiple I. GENERAL PROJECT DESCRIPTION Garfield County’s Land Use and Development Code is available here: https://www.garfield- county.com/community-development/land-use-code/ Temporary Use Permits are described in Section 4-120 and Section 7-1303. The following sections of this preapplication conference summary contain general submittal requirements and process outlines. The Director has indicated that he will refer these Temporary Use applications to the Board of County Commissioners for their decision. Applications for a Temporary Use should be submitted at least 60 days prior to the proposed use. Temporary Use Permits are restricted to a 6-month period and cannot be applied for on the same property more than twice in one 12 month period. There are noticing requirements which will include the start date, operating hours, and duration of the uses. Authorization of property owners needs to be included in compliance with 4-120.B.2.a. Recorded Statements of Authority need to be provided for any LLCs, trusts, or similar entities. The applications should directly respond to items found in 4-120.B.5. Impacts on neighboring properties and infrastructure will be taken into account, so the application should address these 2 topics specifically. The application should address Article 7 Standards. Divisions 1-3 and Section 7- 1301 should be specifically addressed. Any previous approvals on a parcel should be included with an application, and the application should demonstrate continued compliance with those approvals. The applications should provide information such as location, site plans, haul routes, helicopter flight paths, hours of operation, start date, duration, uses, site preparation, and site restoration. Stormwater and traffic should be addressed. If hazardous materials will be stored on site, mitigation practices should be provided to address. Wastewater management systems and water supply should also be addressed. Garfield County’s Environmental Health handles vault and haul permits for those types of wastewater systems. XCEL is undertaking multiple rebuilds of transmission lines throughout Garfield County. At this time, three broad phases are anticipated. Each will have laydown yards that double as helistops to facilitate installation of new poles in difficult terrain. Each yard should have a separate application, though staff will coordinate the review of the applications to minimize review times and hearings. Helicopter deliveries involve FAA approvals. The applications should provide information on these approvals and what mitigation activities will be involved to limit hazards to residents. Glenwood Springs - Mitchell Creek Rebuild which currently has an Location and Extent application under review; will have a single laydown/helistop in unincorporated Garfield County on parcel 218505400065. This yard will primarily be used for storage for helicopter delivery. Steep slopes to the south of this site exist, and access is taken from existing private roads/driveways. The application should demonstrate the adequacy of these systems for the proposed uses. This segment is mostly within incorporated Glenwood Springs. It does cross I70 and the Colorado River, though at this time helicopter operations will be north of these barriers. 6584 Mitchell Creel – Rifle Ute Transmission This 25 mile rebuild is scheduled for 2025 and will have 5 staging areas. Each of these laydown yards will also have helicopter activity. This section may be broken up into two small sections. This section is primarily south of I-70. A map is shown on the following pages. The applicant may need to schedule an update to this preapplication conference summary for this area as they approach the 2025 time frame. A variety of different scale of laydown yard are proposed in this section. Each application should provide specific details on the intensity of its uses to allow for the adequate review of possible impacts on infrastructure and neighbors. 6670 Rifle Ute - De Beque Transmission: This rebuild of approximately 32 miles currently has 2 proposed laydown/helistop facilities. This section is mostly north of the I-70. These facilities will primarily be fly yards with no or limited overnight storage. Materials are expected to be delivered to the sites and then taken from the facility to the construction site the same day. A project overview map is provided on the following pages. 3 Figure 2 6584 Mitchell Creel – Rifle Ute Transmission Figure 1 Glenwood Springs - Mitchell Creek Rebuild 4 Figure 3 6670 Rifle Ute - De Beque Transmission: II. COMPREHENSIVE PLAN Compliance with the comprehensive plan should be shown by any application, though for temporary uses the application may want to focus on the lack of long term impacts and limiting longer negative impacts of alternatives. III. REGULATORY PROVISIONS APPLICANT IS REQUIRED TO ADDRESS The following Sections of the Garfield Land Use and Development Code as amended apply to the Application: • Section 4-103 Administrative Review and Section 4-101 Common Review Procedures • Table 4-201 Submission Requirements and Section 4-203 Description of Submittal Requirements. • Section 4-118 and Section 4-202, as applicable. • Article 7 Standards , as applicable IV. SUBMITTAL REQUIREMENTS As a convenience outlined below is a list of information typically required for this type of application. Section 4-120 lists application materials required for temporary uses. The Director may waiver or require additional submittal requirements in accordance with Section 4-120.B. The following list can function as a checklist for your submittal. 5 General Application Materials including the Application Form (signed), payment of Fees and signed Payment Agreement Form (see attached). o A narrative describing the request and related information. o Proof of ownership. o A recorded Statement of Authority is required for any property owned by an LLC or other entity. o A Letter of Authorization is required if an owner intends to have a representative complete the Application and processing. o A Letter of Permission if property owner is not applicant. o Names and mailing addresses of property owners within 200 ft. of the subject property from Assessor’s Office Records. o Copy of the Preapplication Summary needs to be submitted with the Application. Vicinity Map. Description of Applicant (Section 4-120.B.2). Temporary Use Description which includes relevant information related to use, duration, hours, parking, traffic, sanitation, etc. This should specifically address alterations to existing conditions of approval or waivers of standards being sought as part of the temporary use. Copy of all previous approvals. Impact Analysis describing the anticipated impacts to adjacent properties, infrastructure, and environment. At a minimum it should specifically, it shall address vapor, dust, smoke, noise, light, glare, stormwater, other emanations. Impacts on infrastructure, such as roads, water, wastewater, parks, etc., shall also be addressed. The Application should demonstrate compliance with Section 7-1301 Temporary Use The Application should demonstrate compliance with Article 7 Standards, as applicable. The Application should include a waiver request from submittal requirements according to 4- 202, specifically addressing the review criteria for each waiver request. The Application should include any waivers from Article 7 Standards that the applicant wishes to pursue, in accordance with 4-118. Three hard copies and one digital copy (on a USB drive, for example) of the application are required. Both versions should be split into individual sections. Community Development Staff is available to meet with the Applicant to provide additional information and clarification on any of the submittal requirements and waiver requests. V. REVIEW PROCESS The application shall be reviewed in accordance with the procedures set forth in Section 4-120 of the LUDC. Staff will review the application for completeness, and when complete, refer it to appropriate agencies for technical review. A Director’s Determination or BOCC hearing date shall be established 6 once the application has been determined to be technically complete. Staff will create a report to be submitted to the appropriate decision marker for their decision. Public Hearing(s): X No Public Hearing, Directors Decision (with notice per code) Planning Commission X Board of County Commissioners Board of Adjustment Referral Agencies: As necessary. VI. APPLICATION REVIEW FEES Planning Review Fees: $250 Referral Agency Fees: $na Total Deposit: $250(additional hours are billed at hourly rate of $40.50) VII. GENERAL APPLICATION PROCESSING The foregoing summary is advisory in nature only and is not binding on the County. The summary is based on current zoning, which is subject to change in the future, and upon factual representations that may or may not be accurate. This summary does not create a legal or vested right. The summary is valid for a six-month period, after which an update should be requested. The Applicant is advised that the Application submittal once accepted by the County becomes public information and will be available (including electronically) for review by the public. Proprietary information can be redacted from documents prior to submittal. Pre-application Summary Prepared by: 12/15/2023 Philip Berry, Planner III Date Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix F: Site Plan Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. – Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix G: Drainage Memo Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. 1 Memo Date: Monday, January 23, 2023 Project: Xcel Energy 6584 Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild To: City of Glenwood Springs and Garfield County From: Braileigh Jay – Xcel Energy, Brian Brown – HDR Engineering Subject: Drainage Letter for Above Ground Utility Construction Xcel Energy is rebuilding the existing 2.25 mile 69 kV existing overhead electric line from the Glenwood Springs Substation, near E 6th St and N River St (NE of the Glenwood Hot Springs Pool), generally heading west to the Mitchell Creek Substation which is south of the Colorado River about half a mile east of the intersection of Devereux Road and Midland Avenue. See Figure 1 below for a general alignment of the proposed line. Figure 1 – Proposed Transmission Line alignment 2 Existing Conditions: The current overhead transmission alignment is primarily constructed with direct embed wood structures that may have guy wires or multiple poles depending on site conditions and conductor tensioning. The existing pole diameter at the ground level is between 12 – 32 inches. The ground surfacing under and immediately around the structures is mounded immediately adjacent to pole and then tapers to match surrounding undisturbed grades. The project is generally built on steeper terrain with some flatter areas along the project’s western third. There is existing access grading and limited leveling near structures in steeper hillsides. As grades become less steep, pre-existing graded access is less obvious or does not exist. Due to the nature of this project, there are currently no permanent water quality features nor existing drainage issues or concerns associated with the transmission line. The Site project area is defined by existing Xcel Energy transmission right-of-way (ROW) or easements and additional area that will be utilized by temporary construction easements. In total, this project area is approximately 20 acres (line length x easement width). However, far less of this property will be impacted by construction since impacts are generally limited to the structure locations and associated access, not the entirety of the alignment. The disturbed area is estimated to be approximately 6 acres, excluding the staging area which was permitted separately. The area of existing surface treatments, i.e. aggregate, grass, and dirt, was not calculated as it will not change due to this project. Proposed Conditions: The line rebuild is in the same alignment as the existing line. The new line structures are generally located within 5 - 20 feet of the existing structure locations in the current line alignment. The proposed structures will be a steel monopole design with one H-frame steel pole structure and either direct bury (tangent structures) or have a concrete pier foundation (corner or dead-end) structures. These structures will be 16 – 32 inches in diameter for direct bury structures and roughly 5-foot diameter for concrete pier foundations. The proposed larger diameter single pole will replace multiple smaller wood poles in numerous locations. During the monopole construction, excavated material that will not be placed back into the excavation will be spread in a thin layer around the pole or removed from the site based on site conditions and landowner agreements. Grading Impacts Where feasible, access to many structures for the project will require utilizing existing access to permit truck or equipment access. Localized pad and access grading is temporary, excluding the small pad grading at the helicopter structures. Temporary and permanent grading impacts are listed below: · New STR 114 – The current structure is on an isolated ‘point’ impacted by past grading (after the existing pole was installed) in the area. The new structure location will require grading changes to the ‘point’ to create access pad fill areas for the new pole construction. These changes impact a minor area and will promote increased site infiltration since grades will be reduced from very steep to 2.5H:1V or flatter. Hillside cuts are not required. · New STR 115 – Prior access grading after the existing pole was installed, has created a narrow access path on the north side of the existing and proposed pole sites. This requires minor cut of the remanent point where the pole is located to create a wider drive path by fill. These changes 3 impact a small area and do not substantively change grades nor surfacing of the area. Hillside cuts are not required. · New STR 141 – The proposed grading for structure access and pad is temporary and the most substantive grading change. During construction, run-on flow will be conveyed through the site. Water quality impacts will be mitigated with the use of up-gradient, intermediate, and down- gradient erosion control measures. Post-construction, topographic grades, topsoil cover, and vegetation is to be restored in impacted areas. Drainage paths and runoff are not expected to change, once area is restored. · New STR 145 & 147 – The proposed grading for both structures is on the north side of Midland Avenue. Limited pad grading is required for foundation construction, setting the structure, and tensioning conductor. As these are temporary impacts, the grades, topsoil, and revegetation will be restored to pre-construction conditions after pad removal. · Permanent helicopter pad grading sites, numerous locations – At the majority of helicopter structure locations, the compressor and structure pad sites require two 6-ft by 6-ft pads, one for safe compressor placement and one for safe structure excavation. Unless directed otherwise by landowners, these pad locations are expected to become permanent pads in the event of future pole work and associated pad reconstruction. These exceptionally small areas of grade modification with the same surface vegetation will have a de minimis impact on stormwater volume, time of concentration, direction, velocity, and water quality. Therefore, a hydraulic analysis of these small, isolated grading impacts will not be performed within local basin stormwater areas. Steel Poles The larger diameter of the proposed structures (i.e. a 2.5 foot diameter existing pole with guy wires compared to a 6 foot proposed diameter pole) will have a de minimus impact on the local stormwater drainage given the structure spacing and the proposed pole diameter increase for the larger basin area for either tangent of dead end structures. Outcome: This project will not permanently change the existing surface water flow paths, overall slopes, impervious surface area, nor time of concentration and therefore will not change the runoff volume, runoff peak, nor conveyance path for the alignment. Based on the project type and the absence of permanent stormwater drainage impacts, this type of replacement project does not require permanent water quality features be implemented. HDR Engineering Brian Brown, PE CO PE 41644 Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix H: Geotechnical Engineering Report Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. REPORT COVER PAGE Geotechnical Engineering Report __________________________________________________________________________ Xcel Line 6584 Glenwood Springs to Mitchell Creek Various Locations Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Prepared for: Xcel Energy Services, Inc. Denver, Colorado Prepared by: Terracon Consultants, Inc. Wheat Ridge, Colorado Terracon Consultants, Inc. 10625 W. I-70 Frontage Rd N, Ste 3 Wheat Ridge, Colorado 80033 P (303)423-3300 F (303) 423-3353 terracon.com REPORT COVER LETTER February 16, 2021 Xcel Energy Services, Inc. 1800 Larimer Street, Suite 500 Denver, Colorado 80202 Attn: Mr. Joshua Peterson P: (608) 469-0216 E: Joshua.G.Peterson@xcelenergy.com Re: Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Various Locations Glenwood Springs, Colorado Terracon Project No. 25205018 Mr. Peterson: We have completed the geotechnical engineering services for the project referenced above. This study was performed in general accordance with Purchase Order No. 4500532186 dated February 12, 2020 and subsequent amendments dated January 8, 2021 and February 4, 2021. This report presents the findings of the subsurface exploration and provides geotechnical recommendations concerning earthwork and the design of the proposed transmission line structures. We appreciate the opportunity to be of service to you on this project. If you have any questions concerning this report or if we may be of further service, please contact us. Sincerely, Terracon Consultants, Inc. Scott W. Borecki, P.E. Scott B. Myers, P.E. Project Engineer Regional Senior Consultant Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable REPORT TOPICS REPORT SUMMARY ....................................................................................................... I INTRODUCTION ............................................................................................................. 1 SITE CONDITIONS ......................................................................................................... 1 PROJECT DESCRIPTION .............................................................................................. 2 GEOTECHNICAL CHARACTERIZATION...................................................................... 3 Typical Profile ............................................................................................................................. 3 Groundwater Conditions .............................................................................................................. 4 Geophysical (P-wave and MASW) Survey Interpretation ............................................................. 5 GEOTECHNICAL OVERVIEW ....................................................................................... 5 Existing Fill Materials .................................................................................................................. 6 Boulders and Cobbles ................................................................................................................. 6 Geothermal Aquifer Interaction .................................................................................................... 6 EARTHWORK................................................................................................................. 7 Site Preparation .......................................................................................................................... 7 Material Types ............................................................................................................................ 7 Compaction Requirements .......................................................................................................... 8 Excavation .................................................................................................................................. 9 Grading and Drainage ............................................................................................................... 10 Earthwork Construction Considerations ..................................................................................... 10 STRUCTURE FOUNDATION RECOMMENDATIONS ................................................. 10 General Direct Embed Pole Design and Construction Recommendations .................................. 10 General Drilled Pier Design and Construction Recommendations .............................................. 11 Structure-Specific Design Tables .............................................................................................. 13 SEISMIC CONSIDERATIONS ...................................................................................... 26 CORROSIVITY.............................................................................................................. 26 GENERAL COMMENTS ............................................................................................... 27 Note: This report was originally delivered in a web-based format. For more interactive features, please view your project online at client.terracon.com. ATTACHMENTS EXPLORATION AND TESTING PROCEDURES SITE LOCATION AND EXPLORATION PLANS EXPLORATION RESULTS GEOPHYSICAL RESULTS SUPPORTING INFORMATION Note: Refer to each individual Attachment cover page for a listing of contents. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable i REPORT SUMMARY A geotechnical engineering exploration has been performed for the proposed rebuild of the existing 115 kV Glenwood to Mitchell Creek transmission line 6584 in Glenwood Springs, Colorado. Based on the information obtained from this subsurface exploration and the laboratory testing completed, the site appears suitable for the proposed construction; however, the following geotechnical conditions will need to be considered: Constructing the transmission line structures on drilled pier foundations is considered suitable from a geotechnical viewpoint. This report provides recommendations for the design and construction of drilled pier foundations and direct-embedded steel poles. Up to about 6½ feet of fill materials were encountered in the borings drilled for this exploration. We do not possess any information regarding whether the fill was placed under the observation of a geotechnical engineer. Boulders and cobbles were encountered in most of the borings drilled for this exploration. In order to advance the borings to the requested depths, a downhole hammer (ODEX) drilling technique was used in most of the borings. Difficult excavation and drilled pier installation should be anticipated during the construction of the proposed transmission line structures. Heavy-duty excavation equipment and drilling equipment will be required. Based on the 2015 International Building Code (IBC) Section 1613.3.2, the subsurface conditions encountered in the borings, and the results of the geophysical testing performed at selected locations, the seismic site classification for the sites range from C to D. This summary should be used in conjunction with the entire report for design purposes. It should be recognized that details were not included or fully developed in this section, and the report must be read in its entirety for a comprehensive understanding of the items contained herein. The section titled General Comments should be read for an understanding of the report limitations. Responsive Resourceful Reliable 1 INTRODUC TION Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Various Locations Glenwood Springs, Colorado Terracon Project No. 25205018 February 16, 2021 INTRODUCTION This report presents the results of our subsurface exploration and geotechnical engineering services performed for the proposed Line 6584 Glenwood Springs to Mitchell Creek rebuild project to be located in Glenwood Springs, Colorado. The purpose of these services is to provide information and geotechnical engineering recommendations relative to: Subsurface soil and bedrock conditions Groundwater levels Earthwork Geotechnical design criteria Seismic considerations The geotechnical engineering Scope of Services for this project included advancing nine test borings (designated as Boring Nos. 1, 3, 5 through 8, and 10 through 12) to depths ranging from approximately 29 to 41 feet below existing site grades and performing geophysical explorations at six locations (designated as Geophysics Location Nos. 1 through 4, 9, and 14). Plans showing the site and exploration locations are shown in the Site Location and Exploration Plans and Geophysical Results sections. The results of the laboratory testing performed on soil and bedrock samples obtained from the site during the field exploration are included on the boring logs and/or as separate graphs in the Exploration Results section. The results of the geophysical explorations are included in the Geophysical Results section. SITE CONDITIONS The following description of site conditions is derived from our site visit in association with the field exploration. Item Description Project Location The project is to be located in Glenwood Springs, Colorado. The approximate endpoints of the proposed transmission line improvements are 39.5506°N, 107.3209°W and 39.5598°N, 107.3523°W. See Site Location. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 2 Item Description Existing Improvements The transmission line alignment generally consists of vacant land, residential properties, and commercial properties. Current Ground Cover Ground cover along the proposed transmission line alignment are variable and general consists of grass, weeds, light vegetation, barren land, and asphalt and concrete pavements. Existing Topography The existing grade along the transmission line alignment is variable with elevation differences of up to about 200 feet. Geology Surficial geologic conditions near the site, as mapped by the U.S. Geological Survey (USGS) (1Kirkham, et al, 2008), consist of the following units: MI: Leadville Limestone Pb: Belden Formation Qdfo: Older debris-flow deposits Qdfy: Younger debris-flow deposits Qlo: Loess Qlso: Older landslide deposits Qto: Older terrace alluvium Qtu: Tufa Glenwood Springs is known for its hot springs. Most of the hot springs are reportedly associated with the Leadville Limestone and other carbonate rocks. The geologic conditions presented in this section were obtained by locating the subject site on available large-scale geologic maps. Due to the scales involved, precise location of the site can be difficult to determine. In addition, the large-scale geologic maps describe only general trends. Local variations are possible and site-specific geology may differ from those described above. A site-specific detailed geologic description is beyond the scope of this project. PROJECT DESCRIPTION Our initial understanding of the project was provided in our proposal and was discussed during project planning. Our final understanding of the project conditions is as follows: Item Description Project Description We understand the Line 6584 Glenwood Springs to Mitchell Creek rebuild project consists of rebuilding approximately 1.5 miles of existing 115kV transmission line. 1Kirkham, Robert M.; Streufert, Randall K.; Cappa, James A.; Shaw, Colin A.; Allen, Joseph L.; and Jones, James V., 2008, Geologic Map of the Glenwood Springs Quadrangle, Garfield County, Colorado, Map Series 38, United States Geological Survey. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 3 Item Description Anticipated Foundation Systems We understand the deadend structures will be constructed on cylindrical concrete pier foundations, while the tangent structures will be direct- embedded steel poles. Maximum Loads Axial: 20 to 40 kips (assumed) Lateral (shear): 20 to 60 kips (assumed) Moment: 1,500 to 3,500 kip-ft (assumed) Grading/Slopes None anticipated Underground Utilities No below-grade infrastructure will be installed as part of this project. GEOTECHNICAL CHARACTERIZATION We have developed a general characterization of the subsurface soil, bedrock, and groundwater conditions based upon our review of the data and our understanding of the geologic setting and planned construction. The following sections provide our geotechnical characterization. The geotechnical characterization forms the basis of our geotechnical calculations and evaluation of site preparation, foundation options, and pavement options. As noted in General Comments, the characterization is based upon widely spaced exploration points across the site, and variations are likely. Typical Profile Based on the results of the borings for this exploration, subsurface conditions on the site can be generalized as follows: Material Description Approximate Depth to Bottom of Stratum below Existing Site Grade Consistency/ Relative Density/ Hardness Existing fill materials consisting of clay with varying amounts of gravel, sand, silt, and limestone fragments, and sand with varying amounts of boulders, gravel, silt, and clay About 3½ to 6½ feet Variable Native soil consisting of lean clay with varying amounts of cobbles, boulders, gravel, sand, and silt, and sand with varying amounts of cobbles, boulders, gravel, silt, and clay. About 12 to 41 feet, Maximum depth explored in all the borings except for Boring No. 1 Clay: stiff to hard Sand: loose to very dense Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 4 Material Description Approximate Depth to Bottom of Stratum below Existing Site Grade Consistency/ Relative Density/ Hardness Bedrock consisting of shale About 31 feet, Maximum depth explored in Boring No. 1 Very hard Stratification boundaries on the boring logs represent the approximate location of changes in soil and material types; in situ, the transition between materials may be gradual. Further details of the borings can be found on the boring logs in the Exploration Results. A summary of laboratory test results is included in the Exploration Results. Groundwater Conditions The borings were observed while drilling and upon completion of drilling for the presence and level of groundwater. The water levels encountered in the boreholes can be found on the boring logs in Exploration Results and are summarized below. Boring No. Shallowest depth to groundwater encountered while or upon completion of drilling 1 1 None encountered 3 None encountered 5 None encountered 6 None encountered 7 None encountered 8 None encountered 10 None encountered 11 None encountered 12 About 40 feet 1. Due to safety concerns, borings were backfilled immediately after completion. Therefore, subsequent groundwater measurements were not obtained. These observations represent groundwater conditions at the time of the field exploration and may not be indicative of other times or at other locations. Groundwater levels can be expected to fluctuate with varying seasonal and weather conditions. Zones of perched and/or trapped groundwater may also occur at times in the subsurface soils overlying bedrock, on top of the bedrock surface or within permeable fractures in the bedrock materials. The location and amount of perched water is dependent upon several factors, including hydrologic conditions, type of site development, irrigation demands on or adjacent to the site, fluctuations in water features, seasonal and weather conditions. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 5 Groundwater level fluctuations occur due to seasonal variations in the amount of rainfall, runoff, and other factors not evident at the time the borings were performed. Groundwater levels during construction or at other times in the life of the structures may be higher or lower than the levels indicated on the boring logs. The possibility of groundwater level fluctuations should be considered when developing the design and construction plans for the project. Geophysical (P-wave and MASW) Survey Interpretation Terracon performed geophysical exploration services consisting of seismic refraction and MASW to better define the subsurface conditions at the subject site. Six locations (designated as Geophysics Location Nos. 1 through 4, 9, and 14) were tested in the area of the proposed transmission line structures. Terracon used a seismic refraction system (SRS) consisting of a SeismicSource DAQLink III seismograph and 24 geophones to derive subsurface seismic velocity information. Survey lines ranged from approximately 240 to 300 feet in length and had geophone spacings of 10 to 13 feet. The approximate location and layout of the survey lines are presented in the Geophysical Results. After the geophysical survey line data was processed into velocity profiles, as described in Exploration and Testing Procedures, Boring Nos. 1 and 3 were superimposed on the velocity profiles for Geophysics Location Nos. 1 and 3, respectively. Based on comparison with the velocity profiles and the subsurface conditions encountered in the exploratory borings at the selected geophysics locations, the subsurface material types were generally associated with velocity profiles to estimate the geotechnical design parameters for the proposed structure foundations in areas where exploratory borings could not be drilled. Although we typically recommend borings be performed to confirm the results of the seismic data, we understand that borings could not be performed near the seismic lines due to access conditions. It is important to note that seismic data used in lieu of borings can provide significant information about subsurface conditions, but it cannot provide the same level of geotechnical confidence as borings. The subsurface materials should be confirmed during construction and the design values should be adjusted, as needed. Full-time observation of the structure foundation construction should be performed by the Geotechnical Engineer. GEOTECHNICAL OVERVIEW Based on subsurface conditions encountered in the borings, the site appears suitable for the proposed construction from a geotechnical point of view provided certain precautions and design and construction recommendations outlined in this report are followed. We have identified Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 6 geotechnical conditions that could impact design and construction of the proposed transmission line structures and other site improvements. Existing Fill Materials Up to about 6½ feet of fill materials were encountered in portions of the site. Fill depths presented in the boring logs are approximate and the depth, lateral extents, and composition of fill should be expected to vary. We do not possess any information regarding whether the fill was placed under the observation of a geotechnical engineer. There exists the potential for construction debris and/or domestic trash to be encountered within the fill on some portions of the site. However, the potential for encountering construction debris or domestic trash is considered to be low. The fill materials should be observed for the presence of trash and debris during site grading and construction. The existing fill can be reused as engineered fill below drilling pads or temporary roads, provided the material meets the requirements of imported soils in the Material Types subsection in Earthwork, any deleterious materials are removed, and some movement can be tolerated. Some removal and replacement may be required if unsuitable or soft materials are exposed. Boulders and Cobbles Boulders and cobbles were encountered in Boring Nos. 3, 6, 7, 8, 10, 11, and 12. In order to advance the borings to the requested depths, a downhole hammer (ODEX) drilling technique was used in all the borings except for Boring No. 8. Boulders up to about 2 feet in diameter were encountered within the exploratory borings. Difficult excavation and drilled pier installation should be anticipated during the construction of the proposed transmission line structures. Heavy-duty excavation equipment and drilling equipment will be required. Geothermal Aquifer Interaction Based on the subsurface conditions encountered in the borings drilled for this exploration and the anticipated depths of the transmission line structure foundations, it is our opinion that the risk of encountering the geothermal aquifer is considered to be low. In the event that artesian conditions are encountered during the construction of the transmission line structure foundations, the contractor should be prepared with a contingency plan to manage the artesian conditions and seal the pier hole. Prior to construction, the contingency plan should be reviewed by the owner and any other entities with jurisdiction. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 7 EARTHWORK The following presents recommendations for site preparation, excavation, subgrade preparation, and placement of engineered fills on the project. All earthwork on the project should be observed and evaluated by Terracon. Site Preparation Strip and remove existing vegetation, organics, and other deleterious materials from proposed improvement areas. All exposed surfaces should be free of mounds and depressions that could prevent uniform compaction if new fill will be placed in these areas. Stripped materials consisting of vegetation, unsuitable fills, and organic materials should be wasted from the site or used to revegetate landscaped areas or exposed slopes after completion of grading operations. In areas where new fill will be places, where possible, the site should be initially graded to create a relatively level surface to receive fill and to provide for a relatively uniform thickness of fill beneath the proposed improvement areas. All exposed areas that will receive fill, once properly cleared, should be scarified to a minimum depth of 12 inches, conditioned to near optimum moisture content, and compacted. It is imperative the moisture content of prepared materials be protected from moisture loss. It is anticipated that the installation of the transmission line structures will require the use of heavy- duty construction equipment when installing the drilled piers through the cobbles and boulders and into the underlying bedrock. The stability of subgrade soils may be affected by precipitation, repetitive construction traffic, or other factors. If unstable conditions are encountered or develop during construction, workability may be improved by overexcavation of wet zones and mixing these soils with crushed gravel. Use of geotextiles could also be considered as a stabilization technique. Lightweight excavation equipment may be required to reduce subgrade pumping. Material Types Fill for this project should consist of engineered fill. Engineered fill is fill that meets the criteria presented in this report and has been properly documented. Engineered fill should meet the following material property requirements: Fill Type 1,2 USCS Classification Acceptable Location for Placement On-site clay soils CL, CH, CL-ML On-site clay soils are considered suitable for reuse as compacted fill for this project, provided the soils meet the gradation requirements presented in this section. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 8 Fill Type 1,2 USCS Classification Acceptable Location for Placement On-site sand soils SP, SC, SM On-site sand soils are considered suitable for reuse as compacted fill for this project, provided the soils meet the gradation requirements presented in this section. Imported soils Varies Imported soils meeting the gradation outlined herein can be considered acceptable for use as compacted fill for this project. 1. Controlled, compacted fill should consist of approved materials that are free of organic matter and debris. Frozen material should not be used, and fill should not be placed on a frozen subgrade. A sample of each material type should be submitted to the geotechnical engineer for evaluation. 2. Care should be taken during the fill placement process to avoid zones of dis-similar fill. Improvements constructed over varying fill types are at a higher risk of differential movement compared to improvements over a uniform fill zone. Imported soils and on-site materials for engineered fill (if required) should meet the following material property requirements: Gradation Percent Finer by Weight (ASTM C136) 100 No. 4 Sieve 50-100 No. 200 Sieve 15-75 Liquid Limit .................................................. 30 (max) Plasticity Index ............................................ 15 (max) Maximum Expansive Potential (%) .............. 1.0* *Measured on a sample compacted to approximately 95 percent of the ASTM D698 maximum dry density at optimum water content. The sample is confined under a 200-psf surcharge and submerged. Compaction Requirements Engineered fill should be placed and compacted in horizontal lifts, using equipment and procedures that will produce recommended moisture contents and densities throughout the lift. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 9 Item Description Fill Lift Thickness 8 inches or less in loose thickness when heavy, self- propelled compaction equipment is used 4 to 6 inches in loose thickness when hand-guided equipment (e.g. jumping jack, plate compactor) is used Compaction Requirements 1,2 maximum dry density (ASTM D698) for clay soils and a maximum dry density for sand soils. Moisture Content of Cohesive Soils (Clay Soils) 3 0 to +3% of the optimum moisture content Moisture Content of Cohesionless Soils (Sand Soils) -2 to +2% of the optimum moisture content 1. We recommend that engineered fill be tested for water content and comp action during placement. Should the results of the in-place density tests indicate the specified water or compaction limits have not been met, the area represented by the test should be reworked and retested as required until the specified water and compaction requirements are achieved. 2. Water levels should be maintained low enough to allow f or satisfactory compaction to be achieved without the compacted fill material pumping when proofrolled. 3. Moisture conditioned clay soils should not be allowed to dry out . A loss of moisture within these materials could result in an increase in the material s expansive potential. Subsequent wetting of these materials could result in undesirable movement. Excavation Excavations into the subsurface soils and bedrock will encounter a variety of conditions. The individual contractor(s) is responsible for designing and constructing stable, temporary excavations as required to maintain stability of both the excavation sides and bottom. All excavations should be sloped or shored in the interest of safety following local and federal regulations, including current Occupational Safety and Health Administration (OSHA) excavation and trench safety standards. Soils and bedrock penetrated by the proposed excavations may vary significantly across the site. The soil and bedrock classifications are based solely on the materials encountered in the exploratory borings. The contractor should verify that similar conditions exist throughout the proposed area of excavation. If different subsurface conditions are encountered at the time of construction, the actual conditions should be evaluated to determine any excavation modifications necessary to maintain safe conditions. Construction site safety is the sole responsibility of the contractor who controls the means, methods, and sequencing of construction operations. Under no circumstances shall the information provided herein be interpreted to mean Terracon is assuming responsibility for construction site safety or the contractor's activities; such responsibility shall neither be implied nor inferred. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 10 Grading and Drainage All grades must provide effective drainage away from the proposed transmission line structures during and after construction and should be maintained throughout the life of the structures. Water retained next to structures can result in soil movements greater than those discussed in this report. Earthwork Construction Considerations The Geotechnical Engineer should be retained during the construction phase of the project to observe earthwork and to perform necessary tests and observations during foundation excavation and construction. The stability of subgrade soils may be affected by precipitation, repetitive construction traffic, or other factors. If unstable conditions develop along construction and maintenance access roads during general construction operations, recommended options for subgrade stabilization include removal and replacement of unstable soils or mixing unstable soils with crushed gravel. The use of geotextiles could also be considered as a stabilization technique. STRUCTURE FOUNDATION RECOMMENDATIONS We understand the deadend structures will be constructed on cylindrical concrete pier foundations, while the tangent structures will be direct-embedded steel poles. The following sections present criteria for each structure location and may be used for either direct-embed structures or structures constructed on drilled piers. General Direct Embed Pole Design and Construction Recommendations The maximum end bearing pressures given in the specific structure design tables are based on the cross-sectional area of the tip of the pole. Side resistance should be applied to the surface area of the pole for that given length interval below a depth of 3 feet to reduce the effect of frost. The combination of skin friction and end bearing pressure can be used to determine the vertical compression capacity. The skin friction value should be used to determine the uplift capacity of the pole. For lateral load and overturning design, we have included LPILE© and MFAD parameters in the structure specific design tables. Lateral load design parameters are valid for maximum soil strain of 1 percent for the native soils acting over a distance of one shaft diameter. The passive pressure, coefficient of horizontal subgrade reaction, and LPILE © parameters presented in the specific structure design tables are ultimate values; therefore, appropriate factors of safety should be applied in the design. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 11 Because cobbles and boulders were encountered in the borings, heavy-duty construction equipment will be required to install the transmission poles. Due to potential sloughing and raveling, foundation concrete quantities may exceed calculated geometric volumes. General Drilled Pier Design and Construction Recommendations The end bearing capacities given are based on the cross-sectional area of the tip of the pier. Side resistance should be applied to the surface area of the drilled pier for that given length interval below a depth of 3 feet to reduce the effect of frost. The combination of skin friction and end bearing pressure can be used to determine the vertical compression capacity. The skin friction iers. The contribution of soil resistance within the frost zone should be neglected in computations of vertical and lateral capacity. For lateral load and overturning design, we have included LPILE and MFAD parameters in the structures-specific design tables. Lateral load design parameters are valid for maximum soil strain of 1 percent for the native soils acting over a distance of one shaft diameter. The passive pressure, coefficient of horizontal subgrade reaction, and LPILE parameters presented in the structure specific design tables are ultimate values; therefore, appropriate factors of safety should be applied in the pier design. Piers should be considered to work in group action if the horizontal center-to-center spacing is less than three pier diameters. A minimum practical horizontal center to center spacing between piers of at least three diameters should be maintained, and adjacent piers should bottom at the same elevation. The capacity of individual piers must be reduced when considering the effects of group action. Capacity reduction is a function of pier spacing and the number of piers within a group. The following table presents capacity reductions for closely spaced piers. Description Value Drilled Pier Spacing (Center-to-Center) >3 diameters >2 to 3 diameters 1 to 2 diameters Pier Capacity Reduction None 30 percent 50 percent 1. End bearing values do not need to be reduced for closely spaced piers, if bottoms of piers are at the same elevation. Lateral analysis should account for the center-to-center spacing and p-y multiplier values per the following table: Pier Center-to-Center Spacing (In Direction of Loading) p-multiplier, pM Row 1 p-multiplier, pM Row 2 p-multiplier, pM Row 3 and Higher 3 x diameter 0.8 0.4 0.3 Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 12 Pier Center-to-Center Spacing (In Direction of Loading) p-multiplier, pM Row 1 p-multiplier, pM Row 2 p-multiplier, pM Row 3 and Higher 5 x diameter 1.0 0.85 0.7 Boulders and cobbles were encountered within the borings drilled for this exploration. Specialized drilling equipment and/or techniques will be necessary to drill through boulders and cobbles to the anticipated pier depths. The individual contractor(s) should be provided a copy of this report to make their own determination about the means and methods required. Groundwater (if encountered) should be removed from each pier hole prior to concrete placement. Pier concrete should be placed immediately after completion of drilling and cleaning. If pier concrete cannot be placed in dry conditions, a tremie should be used for concrete placement. Due to potential sloughing and raveling, foundation concrete quantities may exceed calculated geometric volumes. Pier-bearing surfaces must be cleaned prior to concrete placement. A Terracon representative should observe the bearing surface and shaft configuration. Pier casing may be required if groundwater, loose soils, or caving soils are encountered. Casing should be withdrawn in a slow continuous manner maintaining a sufficient head of concrete to prevent infiltration of water or caving soils or the creation of voids in pier concrete. Pier concrete should have a relatively high fluidity when placed in cased pier holes or through a tremie. Pier concrete with slump in the range of 5 to 7 inches is recommended for uncased piers. For cased piers, a slump in the range of 7 to 9 inches is recommended. Pier bearing surfaces must be cleaned prior to concrete placement. A representative of the geotechnical engineer should observe the bearing surface, shaft configuration and shear ring installation. Free-fall concrete placement in piers will only be acceptable if provisions are taken to avoid striking the concrete on the sides of the hole or reinforcing steel. The use of a bottom-dump hopper, or an elephant's trunk discharging near the bottom of the hole where concrete segregation will be reduced, is recommended. The top of the piers should be cylindrical in shape. Forms may be necessary at the top of the piers in order to minimize the disturbance of the soils and to maintain a cylindrical shape. Failure to provide this shape (i.e., allowing mushrooming of pier tops) may result in additional uplift forces and unanticipated movement. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 13 For drilled piers for the proposed dead-end structures for this project, we recommend the following: Description Value Minimum length 15 feet Pier concrete slump (uncased piers) 5 to 7 inches Pier concrete slump (cased piers) 7 to 9 inches Approximate total movement 1 About 1 inch 1. Additional foundation movements could occur if water from any source infiltrates the foundation material; therefore, proper drainage and irrigation practices should be incorporated into the design and operation of the facility. Failure to maintain water content of the subsurface materials and positive drainage will nullify the movement estimates provided above. Structure-Specific Design Tables The structure-specific design tables are presented on the following pages. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 14 Boring No. 1 Description Material Type Native Sand Soils Native Clay Soils Shale Depth Below Existing Site Grade (feet) 3 to 4 4 to 12 12 to 31 LPile Soil Type Sand (Reese) Stiff clay w/out free water Stiff clay w/out free water Effective Unit Weight (pcf) 1 120 115 125 Angle of Internal Friction, (°) 34 0 0 Undrained Cohesion, c (psf) 0 1,000 4,000 Lateral Modulus, K (pci) 60 Static 1,000 Cyclic 400 Static 2,000 Cyclic 800 Strain at 50% of Maximum Stress, 50 N/A 0.005 0.004 Modulus of Deformation, Ep (ksi) 2.5 1.5 5.0 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 1.0 0.05 4.0 0.4 20.0 2.0 1. Groundwater was not encountered in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the bearing stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of th e borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 15 Boring No. 3 Description Material Type Clay Fill Materials Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 4 4 to 40 LPile Soil Type Stiff clay w/out free water Sand (Reese) Effective Unit Weight (pcf) 1 115 120 Angle of Internal Friction, (°) 0 34 Undrained Cohesion, c (psf) 2,000 0 Lateral Modulus, K (pci) Static 2,000 Cyclic 800 125 Strain at 50% of Maximum Stress, 50 0.004 -- Modulus of Deformation, Ep (ksi) 1.0 3.5 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 2.0 0.2 8.0 0.4 1. Groundwater was not encountered in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the bearing stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 16 Boring No. 5 Description Material Type Clay Fill Materials Native Sand Soils Native Clay and Clayey Sand Soils Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 3½ 3½ to 18 18 to 38 38 to 41 LPile Soil Type Stiff clay w/out free water Sand (Reese) Stiff clay w/out free water Sand (Reese) Effective Unit Weight (pcf) 1 115 120 120 120 Angle of Internal Friction, (°) 0 34 0 34 Undrained Cohesion, c (psf) 2,000 0 2,500 0 Lateral Modulus, K (pci) Static 2,000 Cyclic 800 60 Static 1,000 Cyclic 400 60 Strain at 50% of Maximum Stress, 50 0.004 N/A 0.005 N/A Modulus of Deformation, Ep (ksi) 1.0 2.5 1.5 2.5 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 2.0 0.2 8.0 0.4 4.0 0.4 8.0 0.4 1. Groundwater was not encountered in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the bearing stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for upli ft loading. Effective weight of shaft can be added to uplift load capacity. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 17 Boring No. 6 Description Material Type Native Clay Soils Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 7 7 to 41 LPile Soil Type Stiff clay w/out free water Sand (Reese) Effective Unit Weight (pcf) 1 115 125 Angle of Internal Friction, (°) 0 34 Undrained Cohesion, c (psf) 4,000 0 Lateral Modulus, K (pci) Static 2,000 Cyclic 800 125 Strain at 50% of Maximum Stress, 50 0.004 N/A Modulus of Deformation, Ep (ksi) 2.0 4.0 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 6.0 0.6 8.0 0.6 1. Groundwater was not encountered in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the bearing stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 18 Boring No. 7 Description Material Type Native Clay Soils Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 12 12 to 41 LPile Soil Type Stiff clay w/out free water Sand (Reese) Effective Unit Weight (pcf) 1 115 125 Angle of Internal Friction, (°) 0 34 Undrained Cohesion, c (psf) 4,000 0 Lateral Modulus, K (pci) Static 2,000 Cyclic 800 125 Strain at 50% of Maximum Stress, 50 0.004 N/A Modulus of Deformation, Ep (ksi) 2.0 4.0 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 6.0 0.6 8.0 0.6 1. Groundwater was not encountered in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the bearing stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 19 Boring No. 8 Description Material Type Native Sand Soils Native Clay Soils Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 9 9 to 17 17 to 41 LPile Soil Type Sand (Reese) Stiff clay w/out free water Sand (Reese) Effective Unit Weight (pcf) 1 115 115 125 Angle of Internal Friction, (°) 34 0 34 Undrained Cohesion, c (psf) 0 4,000 0 Lateral Modulus, K (pci) 60 Static 1,000 Cyclic 400 125 Strain at 50% of Maximum Stress, 50 N/A 0.005 N/A Modulus of Deformation, Ep (ksi) 1.5 1.5 4.0 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 4.0 0.1 4.0 0.4 8.0 0.6 1. Groundwater was not encountered in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the bearing stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 20 Boring No. 10 Description Material Type Sand Fill Materials Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 4 4 to 41 LPile Soil Type Sand (Reese) Sand (Reese) Effective Unit Weight (pcf) 1 115 125 Angle of Internal Friction, (°) 32 34 Undrained Cohesion, c (psf) 0 0 Lateral Modulus, K (pci) 60 125 Strain at 50% of Maximum Stress, 50 N/A N/A Modulus of Deformation, Ep (ksi) 1.0 4.0 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 1.0 0.05 8.0 0.6 1. Groundwater was not encountered in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the bearing stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 21 Boring No. 11 Description Material Type Clay Fill Materials Native Clay Soils Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 4 4 to 17 17 to 29 LPile Soil Type Stiff clay w/out free water Stiff clay w/out free water Sand (Reese) Effective Unit Weight (pcf) 1 110 115 115 Angle of Internal Friction, (°) 0 0 33 Undrained Cohesion, c (psf) 1,000 2,000 0 Lateral Modulus, K (pci) Static 500 Cyclic 200 Static 1,000 Cyclic 400 60 Strain at 50% of Maximum Stress, 50 0.007 0.005 N/A Modulus of Deformation, Ep (ksi) 0.5 0.8 1.5 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 1.0 0.1 3.0 0.3 8.0 0.4 1. Groundwater was not encountered in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the bearing stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 22 Boring No. 12 Description Material Type Sand Fill Materials Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 6½ 6½to 41 LPile Soil Type Sand (Reese) Sand (Reese) Effective Unit Weight (pcf) 1 115 120 Angle of Internal Friction, (°) 32 34 Undrained Cohesion, c (psf) 0 0 Lateral Modulus, K (pci) 60 60 Strain at 50% of Maximum Stress, 50 N/A N/A Modulus of Deformation, Ep (ksi) 1.0 2.5 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 1.0 0.05 8.0 0.4 1. Groundwater was encountered at about 40 feet below grade in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the b earing stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 23 Geophysics Location No. 2 Description Material Type Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 10 10 to 30 30 to 40 LPile Soil Type Sand (Reese) Sand (Reese) Sand (Reese) Effective Unit Weight (pcf) 1 115 120 125 Angle of Internal Friction, (°) 32 34 34 Undrained Cohesion, c (psf) 0 0 0 Lateral Modulus, K (pci) 60 60 125 Strain at 50% of Maximum Stress, 50 --N/A N/A Modulus of Deformation, Ep (ksi) 1.5 2.5 4.0 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 4.0 0.1 8.0 0.4 8.0 0.6 1. Groundwater was not encountered in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the be aring stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. 7. The recommended design parameters presented in this table are ba sed on the geophysical explorations performed at the structure location and using correlations between the exploratory borings and geophysical explorations performed at other locations along the transmission line alignment. The subsurface materials should be confirmed during construction and the design values should be adjusted, as needed. Full-time observation of the structure foundation construction should be performed by the Geotechnical Engineer. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 24 Geophysics Location Nos. 4 and 9 Description Material Type Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 40 LPile Soil Type Sand (Reese) Effective Unit Weight (pcf) 1 115 Angle of Internal Friction, (°) 32 Undrained Cohesion, c (psf) 0 Lateral Modulus, K (pci) 60 Strain at 50% of Maximum Stress, 50 -- Modulus of Deformation, Ep (ksi) 1.5 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 4.0 0.1 1. Based on the nearby borings drilled for this exploration, we do not anticipate groundwater within the upper 40 feet. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into th e bearing stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. 7. The recommended design parameters presented in this table are based on the geophysical explorations performed at the structure locations and using correlations between the exploratory borings and geophysical explorations performed at other locations along the transmission line alignment. The subsurface materials should be confirmed during construction and the design val ues should be adjusted, as needed. Full-time observation of the structure foundation construction should be performed by the Geotechnical Engineer. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 25 Geophysics Location No. 12 Description Material Type Native Sand Soils Depth Below Existing Site Grade (feet) 3 to 30 30 to 40 LPile Soil Type Sand (Reese) Sand (Reese) Effective Unit Weight (pcf) 1 115 125 Angle of Internal Friction, (°) 32 34 Undrained Cohesion, c (psf) 0 0 Lateral Modulus, K (pci) 60 125 Strain at 50% of Maximum Stress, 50 --N/A Modulus of Deformation, Ep (ksi) 1.5 4.0 Allowable Vertical Parameters End Bearing (ksf) 2,3,4 Skin Friction (ksf) 5,6 4.0 0.1 8.0 0.6 1. Groundwater was encountered at about 40 feet below grade in the boring while drilling. 2. A factor of safety of 3 was used to determine the allowable end bearing pressure. 3. Applicable for a minimum 5-foot embedment or one pier diameter into the be aring stratum, whichever is deeper. 4. Values applicable to piers bearing a minimum of 5 feet, or one pier diameter, above the bottom of the borehole. 5. A factor of safety of 2 was used to determine the allowable compressive skin friction. 6. Applicable for compressive loading only. Reduce to 2/3 of value shown for uplift loading. Effective weight of shaft can be added to uplift load capacity. 7. The recommended design parameters presented in this table are based on the geophysical explorations performed at the structure location and using correlations between the exploratory borings and geophysical explorations performed at other locations along the transmission line alignment. The subsurface materials should be confirmed during construction and the design values should be adjusted, as needed. Full-time observation of the structure foundation construction should be performed by the Geotechnical Engineer. Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 26 SEISMIC CONSIDERATIONS Based on our subsurface exploration and laboratory testing, it is our opinion that the soils have a low risk of liquefaction. The following table presents the seismic site classification based on the 2015 International Building Code (IBC), the subsurface conditions encountered within the borings, and the results of the geophysical testing performed at selected locations: Boring/Geophysics Location No. Site Classification 1,2 1 C 3 2 C 3 3 C 3 4 C 3 5 C 6 C 7 C 8 C 9 C 3 10 C 11 D 12 C 14 C 3 1. In general accordance with the 2015 International Building Code, Section 1613.3.2. 2. The 2015 International Building Code (IBC) requires a site subsurface profile determination extending a depth of 100 feet for seismic site classification. The current scope requested does not include the required 100-foot subsurface profile determination. T he deepest borings of this exploration extended to a maximum depth of about 41 feet and this seismic site class definition considers that similar subsurface conditions exist below the maximum depth of the subsurface exploration. 3. The seismic site classification determination was supplemented with the geophysical data collected at this location. CORROSIVITY The following table lists the results of laboratory water-soluble sulfate and pH testing performed on samples obtained during our field exploration. These values should be used to help determine potential corrosive characteristics of the on-site soils with respect to contact with the various underground materials that will be used for project construction. Refer to the Summary of Laboratory Test Results presented in the Exploration Results section for the complete results Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 27 of the corrosivity testing performed on the on-site soils in conjunction with this geotechnical exploration. The corrosion information presented is specific to the samples tested. If the actual soils that will be in contact with the structures at the site are different than those tested, then additional corrosion testing should be performed. Terracon is not a corrosion engineer, and our scope of work was limited to performing corrosion laboratory tests on selected samples, presenting these results, and providing a brief comparison of the results to selected criteria. A qualified corrosion engineer should be consulted if corrosion of underground utilities and structures is a concern. Boring No. Sample Depth (feet) Water-Soluble Sulfate 1 (%) pH 1 0 5 <0.10 7.0 3 0 5 <0.10 7.2 5 0 5 <0.10 6.9 6 0 5 <0.10 6.9 7 0 5 <0.10 7.6 10 0 5 <0.10 6.9 11 0 5 <0.10 8.0 12 0 5 <0.10 6.9 1. Results of water-soluble sulfate testing indicate that samples of the on-site soils have an exposure class of S0 when classified in accordance with Table 19.3.1.1 of the American Concrete Institute (ACI) Design Manual. The results of the testing indicate ASTM Type I Portland Cement is suitable f or project concrete in contact with on-site soils. However, if there is no (or minimal) cost differential, use of ASTM Type II Portland Cement is recommended for additional sulfate resistance of construction concrete. Concrete should be designed in accordance with the provisions of the ACI Design Manual, Section 318, Chapter 19. GENERAL COMMENTS Our analysis and opinions are based upon our understanding of the project, the geotechnical conditions in the area, and the data obtained from our site exploration. Natural variations will occur between exploration point locations or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or after construction. Terracon should be retained as the Geotechnical Engineer, where noted in this report, to provide observation and testing services during pertinent construction phases. If variations appear, we can provide further evaluation and supplemental recommendations. If variations are noted in the absence of our observation and testing services on-site, we should be immediately notified so that we can provide evaluation and supplemental recommendations. Our Scope of Services does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable 28 pollutants, hazardous materials, or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken. Our services and any correspondence or collaboration through this system are intended for the sole benefit and exclusive use of our client for specific application to the project discussed and are accomplished in accordance with generally accepted geotechnical engineering practices with no third-party beneficiaries intended. Any third-party access to services or correspondence is solely for information purposes to support the services provided by Terracon to our client. Reliance upon the services and any work product is limited to our client, and is not intended for third parties. Any use or reliance of the provided information by third parties is done solely at their own risk. No warranties, either express or implied, are intended or made. Site characteristics as provided are for design purposes and not to estimate excavation cost. Any use of our report in that regard is done at the sole risk of the excavating cost estimator as there may be variations on the site that are not apparent in the data that could significantly impact excavation cost. Any parties charged with estimating excavation costs should seek their own site characterization for specific purposes to obtain the specific level of detail necessary for costing. Site safety, and cost estimating including, excavation support, and dewatering requirements/design are the responsibility of others. If changes in the nature, design, or location of the project are planned, our conclusions and recommendations shall not be considered valid unless we review the changes and either verify or modify our conclusions in writing. Responsive Resourceful Reliable ATTACHMENTS Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable EXPLORATION AND TESTING PROCEDURES 1 of 3 EXPLORATION AND TESTING PROCEDURES Field Exploration Boring Layout: The locations of the borings are presented in the Site Location and Exploration Plans. The borings were located in the field by overlaying the site plan on Google Earth, recording the latitude and longitude coordinates, and staking the borings using a handheld, recreational- grade GPS unit. The accuracy of the latitude and longitude values is typically about +/- 25 feet when obtaining the values using this method. The accuracy of the boring locations should only be assumed to the level implied by the methods used. Subsurface Exploration Procedures: The borings were drilled with CME-55 truck-mounted and Diedrich D-50 all-terrain rotary drill rigs with hollow-stem augers and downhole drilling (ODEX) drilling methods. During the drilling operations, lithologic logs of the borings were recorded by the field engineer. Relatively undisturbed samples were obtained at selected intervals using a 2½-inch outside diameter modified California barrel sampler and disturbed samples were obtained using a 2-inch outside diameter standard split spoon sampler. Bulk samples were obtained from auger cuttings. Penetration resistance values were recorded in a manner similar to the standard penetration test (SPT). This test consists of driving the sampler into the ground with a 140-pound hammer free falling through a distance of 30 inches. The number of blows required to advance the barrel sampler 12 inches (18 inches for standard split-spoon samplers, final 12 inches are recorded) or the interval indicated is recorded and can be correlated to the standard penetration resistance value (N-value). The blow count values are indicated on the boring logs at the respective sample depths, barrel sampler blow counts are not considered N- values. An automatic hammer was used to advance the samplers in the borings performed on this site. A greater efficiency is typically achieved with the automatic hammer compared to the conventional safety hammer operated with a cathead and rope. Published correlations between the SPT values and soil properties are based on the lower efficiency cathead and rope method. This higher efficiency affects the standard penetration resistance blow count value by increasing the penetration per hammer blow over what would be obtained using the cathead and rope method. The effect of the automatic hammer's efficiency has been considered in the interpretation and analysis of the subsurface information for this report. The standard penetration test provides a reasonable indication of the in-place density of sandy type materials, but only provides an indication of the relative stiffness of cohesive materials since the blow count in these soils may be affected by the moisture content of the soils. In addition, considerable care should be exercised in interpreting the N-values in gravelly soils, particularly where the size of the gravel particle exceeds the inside diameter of the sampler. Groundwater measurements were obtained in the borings at the time of drilling. Due to safety concerns, the borings were backfilled with auger cuttings and patched with cold patch asphalt Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable EXPLORATION AND TESTING PROCEDURES 2 of 3 (where applicable) after drilling. Some settlement of the backfill and patches may occur and should be repaired as soon as possible. Geophysical Exploration Procedures: Terracon performed geophysical exploration services consisting of seismic refraction and MASW at six locations. Survey lines ranged from approximately 240 to 300 feet in length and had a geophone spacings of 10 to 13 feet. Terracon used a seismic refraction system (SRS) consisting of a SeismicSource DAQLink III seismograph and 24 geophones to derive subsurface seismic velocity information. The approximate location and layout of the survey lines are presented in the Geophysical Results. First-arrival travel times of compressive waves (P-waves) produced by a P-wave source were recorded. Using only the first-arrival travel times and survey geometry, the data was forward modeled using a non-linear optimization technique called adaptive simulated annealing. This algorithm determines the compressive wave velocity model for a corresponding depth and resolution with the minimum travel-time error without searching through every possible model. Multi-channel analysis of surface waves (MASW) was performed by collecting surface waves created by a seismic source consisting of a sledgehammer and a metal plate. The data was then processed using dispersion analysis software (SurfSeis, engineered by the Kansas Geological Survey) that extracts the fundamental-mode dispersion curve(s). The curves are inverted and modeled to yield a 1D shear-wave velocity profile at the center point of the array for a corresponding depth. Laboratory Testing Samples retrieved during the field exploration were returned to the laboratory for observation by the project geotechnical engineer and were classified in general accordance with the Unified Soil Classification System presented in the Supporting Information. An applicable laboratory-testing program was formulated to determine engineering properties of the subsurface materials. Following the completion of the laboratory testing, the field descriptions were confirmed or modified as necessary, and the boring logs were prepared. The boring logs are included in the Exploration Results. Laboratory test results are included in the Exploration Results. These results were used for the geotechnical engineering analyses and the development of foundation and earthwork recommendations. Laboratory tests were performed in general accordance with the applicable local or other accepted standards. Selected soil samples were tested for the following engineering properties: Water content Dry density Grain size distribution Atterberg limits Water-soluble sulfate content pH Geotechnical Engineering Report Xcel Line 6584 Glenwood Springs to Mitchell Creek Glenwood Springs, Colorado February 16, 2021 Terracon Project No. 25205018 Responsive Resourceful Reliable EXPLORATION AND TESTING PROCEDURES 3 of 3 Responsive Resourceful Reliable SITE LOCATION AND EXPLORATION PLANS Contents: Site Location Plan Exploration Plan with Aerial Image Note: All attachments are one page unless noted above. Responsive Resourceful Reliable EXPLORATION RESULTS Contents: Boring Logs (Boring Nos. 1, 3, 5 through 8, and 10 through 12) Grain Size Distribution (3 pages) Summary of Laboratory Test Results Note: All attachments are one page unless noted above. Responsive Resourceful Reliable GEOPHYSICAL RESULTS Contents: Geophysical Exploration Plan Shear Wave Velocity Profile (6 pages) P-Wave Velocity Profile (6 pages) Note: All attachments are one page unless noted above. Ge o p h y s i c a l E x p l o r a t i o n P l a n KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : 25 2 0 5 0 1 8 Depth, ft Sh e a r - W a v e V e l o c i t y , f t / s 25 2 0 5 0 1 8 Sh e a r W a v e V e l o c i t y P r o f i l e KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : 58 8 0 58 7 0 58 3 0 58 0 0 Approximate Elevation, ft Depth, ft KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : 58 2 5 Approximate Elevation, ft Sh e a r W a v e V e l o c i t y P r o f i l e Depth, ft 25 2 0 5 0 1 8 KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : 59 0 5 Approximate Elevation, ft Sh e a r W a v e V e l o c i t y P r o f i l e Depth, ft 25 2 0 5 0 1 8 KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : 57 9 0 Approximate Elevation, ft Sh e a r W a v e V e l o c i t y P r o f i l e Depth, ft 25 2 0 5 0 1 8 KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : 58 1 0 57 8 0 57 7 0 57 4 0 Approximate Elevation, ft Sh e a r W a v e V e l o c i t y P r o f i l e Depth, ft 25 2 0 5 0 1 8 KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : 58 9 0 58 4 0 58 3 0 Approximate Elevation, ft Sh e a r W a v e V e l o c i t y P r o f i l e P- W a v e V e l o c i t y P r o f i l e 25 2 0 5 0 1 8 KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : 25 2 0 5 0 1 8 KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : P- W a v e V e l o c i t y P r o f i l e 25 2 0 5 0 1 8 KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : Ge o p h o n e L o c a t i o n s P- W a v e V e l o c i t y P r o f i l e 25 2 0 5 0 1 8 KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : Ge o p h o n e L o c a t i o n s P- W a v e V e l o c i t y P r o f i l e 25 2 0 5 0 1 8 KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : P- W a v e V e l o c i t y P r o f i l e 25 2 0 5 0 1 8 KT J Pr o j e c t M a n a g e r : Dr a w n b y : Ap p r o v e d b y : Pr o j e c t N o . Sc a l e : Fi l e N a m e : Da t e : P- W a v e V e l o c i t y P r o f i l e Responsive Resourceful Reliable SUPPORTING INFORMATION Contents: General Notes Unified Soil Classification System Note: All attachments are one page unless noted above. Soft UNIFIED SOIL CLASSIFICATION SYSTEM Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A Soil Classification Group Symbol Group Name B Coarse Grained Soils: More than 50% retained on No. 200 sieve Gravels: More than 50% of coarse fraction retained on No. 4 sieve Clean Gravels: Less than 5% fines C Cu 4 and 1 Cc 3 E GW Well-graded gravel F Cu 4 and/or 1 Cc 3 E GP Poorly graded gravel F Gravels with Fines: More than 12% fines C Fines classify as ML or MH GM Silty gravel F,G,H Fines classify as CL or CH GC Clayey gravel F,G,H Sands: 50% or more of coarse fraction passes No. 4 sieve Clean Sands: Less than 5% fines D Cu 6 and 1 Cc 3 E SW Well-graded sand I Cu 6 and/or 1 Cc 3 E SP Poorly graded sand I Sands with Fines: More than 12% fines D Fines classify as ML or MH SM Silty sand G,H,I Fines classify as CL or CH SC Clayey sand G,H,I Fine-Grained Soils: 50% or more passes the No. 200 sieve Silts and Clays: Liquid limit less than 50 Inorganic:PI J CL Lean clay K,L,M PI J ML Silt K,L,M Organic:Liquid limit - oven dried 0.75 OL Organic clay K,L,M,N Liquid limit - not dried Organic silt K,L,M,O Silts and Clays: Liquid limit 50 or more Inorganic:CH Fat clay K,L,M MH Elastic Silt K,L,M Organic:Liquid limit - oven dried 0.75 OH Organic clay K,L,M,P Liquid limit - not dried Organic silt K,L,M,Q Highly organic soils:Primarily organic matter, dark in color, and organic odor PT Peat A Based on the material passing the 3-inch (75-mm) sieve B If field sample C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay. D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay E Cu = D60/D10 Cc = 6010 2 30 DxD )(D F If soil contains G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM. H I If soil contains J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. K whichever is predominant. L If soil contains group name. M If soil contains 30% plus No. 200, predominantly gravel, add N PI O PI P PI plots on or above Q Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix I: Revegetation Plan Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. 1 Memo Date: Monday, January 22, 2024 Project: 6584 Glenwood Springs Substation to Mitchell Creek Substation Electric Transmission Line Rebuild To: City of Glenwood Springs & Garfield County, Colorado From: Brian Brown – HDR Engineering Subject: Revegetation Plan Public Service Company of Colorado, a Colorado corporation conducting business as Xcel Energy, must replace the existing transmission line between the Glenwood Springs to Mitchell Creek Substations. This line crosses land within the City of Glenwood Springs (City) and in unincorporated Garfield County (County). The new structures will be within the existing transmission easement and accessed via existing private or public roads, existing and new access routes, by walk-in, or by helicopter. Temporary and permanent grading disturbance has been minimized due to a variety of reasons including the challenges of reestablishing revegetation in disturbed areas. Xcel Energy has chosen to call this a Revegetation Plan as opposed to a Landscaping Plan as the intent is to restore surface native type ground cover without the larger planting and irrigation effort often associated with a Landscaping Plan. While there are multiple construction types for this project, i.e. temporary pad grading, temporary access grading, structure base excavation, etc., they are all fairly similar. Below is the general sequential approach to minimize disturbance and promote revegetation across the project. This will have to be slightly customized to each construction type and site conditions. 1. Prior to the start of construction, a surveyor will stake pole locations, off-sets, line easement limits, access routes, temporary construction areas, and other locations of importance where field delineation is beneficial. 2. Appropriate Xcel Energy staff, line construction contractor, foundation contractor, earthwork contractor, and erosion control contractor will meet on-site to review the delineated construction impact limits. 3. Flagging or paint used to delineate where perimeter erosion control measures should be placed based on disturbance limits defined by Xcel Energy construction team (item 2 above). 4. Xcel Energy’s erosion control plan developer or erosion control install contractor will collect multiple representative topsoil soil samples for analysis along the transmission line. This analysis will focus on the potential for possible soil amendments (primarily nitrogen, phosphorus, and potassium) during seeding. 3 – 6 samples are expected based on the varying soil conditions along the line. 5. Erosion control contractor team to install perimeter erosion control measures, typically construction fence, boundary fence, sediment control logs, rock logs, and vehicle tracking control per the requirements identified in the State Stormwater Management Plan (SWMP) and City and County Grading permits. 2 6. Perform pre-construction meeting with City and County assuming that inspection and sign-off on erosion control measures is a condition of both jurisdiction’s Grading Permits. 7. Only as necessary for project, trim and remove vegetation for off-site disposal that will directly impact site grading or access. Xcel Energy to utilize trimming as much as practicable to keep root structure in place. 8. In areas where grading (temporary or permanent) is required, strip topsoil (assume top 4 inches of soil) for reuse on site. Topsoil to be segregated from other material. Topsoil to be placed along access or in other areas adjacent grading. Topsoil may be transported from immediate work area due to space constraints. Topsoil that is stockpiled for more than 14 days will be seeded for temporary stabilization. Topsoil stockpiles that are to remain dormant for more than 14 days are to have side slopes no steeper than 1H:1V. 9. Topsoil stockpiles may be placed on undisturbed adjacent ground. In this case, Xcel Energy will place a separation fabric, i.e. Mirafi 140N or like, to provide a physical indicator as to where the stockpile ends and native ground begins. Xcel Energy has had success with this approach as it reduces unwanted disturbance of native ground and allows an undisturbed but lightly ‘compressed’ topsoil layer to bounce back once topsoil and separation fabric is removed. 10. Once permanent cut/fill slopes are graded (primarily compressor pads and structure pads in helicopter delivery locations), they will be covered with topsoil within 14 days and seeded and mulched within another 14 days. This will allow permanent cut/fill face revegetation to commence as soon as possible. Work areas where active construction is anticipated, i.e. flat pad work area is not to be topsoil covered until construction work has ceased. Once construction of permanent pads has ceased, topsoil cover is to be completed within 14 days and seeding and mulching to follow within another 14 days. 11. Once temporary cut/fill slopes are graded, they will be covered with a cover crop within 14 days. This cover crop is to be maintained until work has ceased and permanent grading is restored. Restoration from temporary construction impacts are to include replacement of topsoil, seeding, and mulching. 12. Subgrade excavation material, from grading or structure excavation, will be spread on the access road, exported from the site for off-site disposal, or stockpiled in immediate or near-by work area for future use, particularly in areas with temporary grading impacts that are to have grades restored. Like the topsoil above, subsoil that is stockpiled on undisturbed ground is to have a separation fabric below the stockpile to clearly distinguish between native grade and stockpile material. This will minimize disturbance of the native grade and allow this compressed native grade to bounce back once stockpile and separation fabric is removed. Note: subgrade material is not to be spread on-site in a manner that increases the area of disturbance, i.e. broadcast or pushed outside grading disturbance limit required for drive surface or equipment pad needs. 13. Once construction is completed at a site for permanent grading impacts, i.e. conductor pull/tensioning pads and access roads, the site soil is to be ripped to loosen the subgrade due to soil compaction during construction. Following decompaction, topsoil is to be placed at a depth of 4 inches in a loose manner ready to accept seed. Unlike most topsoil requirements, rock of various gravel sizes less than 6 inches diameter is expected in the topsoil layer which is indicative of native topsoil in this area. 14. Once construction is completed at a site for temporary grading impacts, i.e. mini-excavator pads, the site rough grades are to be reestablished and the subgrade soil is to be bucket compacted to a ‘firm’ condition. Following compaction, topsoil is to be placed at a depth of 4 inches in a smooth but loose manner ready to accept seed. Unlike most topsoil requirements, rock of various gravel sizes less than 6 inches diameter is expected in the topsoil layer and is indicative of native topsoil in this area. 3 15. Soil amendments are to be added per soil analytic recommendations via mechanical broadcast or hydraulic application. City and County approved seed mix is to be spread at appropriate rates given application type, hydraulic, drill, or hand broadcast. The amendment and seed application will vary substantially based on access type with helicopter structures having a different treatment process than areas readily accessible to larger truck traffic, i.e. access for a hydraulic sprayer. In cases of hydraulic application, the seed mix may be applied with the liquid amendment or hand broadcast but in no case is seed to be mixed and applied with mulch. 16. Final erosion control cover for seeded areas will vary based on access to disturbance areas. Helicopter access areas will not have mulch applied as the impact areas are a small footprint, hydraulic and crimp mulching is not available to these sites, and broadcast straw mulch is generally not effective as the product is blown away. Truck access areas will have either straw crimp mulch (on grades less than 10 percent and low rock content soil) or a high quality hydraulically applied mulch, i.e. Flexterra HP-FGM or like, on grades exceeding 10 percent. Xcel Energy generally does not support using erosion control blankets on this project due to concerns about reduced blanket to soil contact and synthetic mesh blankets having a high synthetic content which leads to a wildlife entrapment hazard. 17. Xcel Energy will change erosion control inspection schedule from weekly to monthly inspections once initial stabilization measures (seeding and mulching) have been completed. If there are areas of concern identified during the monthly inspection that need to be addressed (i.e. erosion or lack of revegetation growth), the revegetation contractor will return to the site to address identified issues. 18. Per the required State (SWMP) and local (Grading Permits), Xcel energy will continue to maintain structural erosion control measures across the project until no longer necessary. These will primarily include down-gradient sediment control logs but may include other control measures. The sediment control logs will be fully biodegradable to reduce wildlife entrapment hazards. These measures will be removed when no longer required and seed will be hand broadcast in areas where removal has exposed or disturbed less vegetated soil. 19. Once site has met plant density cover requirements, Xcel Energy will request a post-construction site visit with the City and/or County for jurisdiction closure concurrence. NOTES: · Xcel Energy’s ability to stabilize disturbed areas with vegetation is dependent on many factors within Xcel Energy control. Unfortunately, favorable moisture conditions for germination and continued growth are beyond Xcel Energy control and a key determinate for revegetation. Xcel Energy anticipates adequate revegetation will take multiple years. Xcel Energy frequently returns to sites multiple times that are in the vegetation growth phase to address areas of erosion and reseed and/or mulch as necessary to promote vegetation stabilization. · Xcel Energy hires a separate third-party company to perform the erosion control installation, maintenance, and revegetation as well as another third-party company to perform regular erosion control inspections. These companies have long standing relationships with Xcel Energy. With this approach, Xcel Energy has trained the installation company and inspection company to meet Xcel Energy’s standards and to stay in compliance with state and local permit conditions which improve the restoration trajectory. Xcel Energy’s practice is to continue inspection and maintenance, both performed by third party contractors, until site revegetation is established. Access for the post construction inspection and maintenance will be over prescriptive rights, land owner allowed access, temporary construction easements, and the transmission line easement. 4 · See Grading Plan submittal for location and discussion of temporary or permanent grading impact areas. · Walk in only access paths are assumed to not create a disturbance that requires revegetation. · The staging area north of Structure 125 may not be restored with revegetation depending on landowner agreements. This gravel pit area may be stabilized with native or imported aggregate surfacing. Seed Mix: The following seed mix was provided by Granite Seed Company specific to Glenwood Springs with the intention of including grasses, forbs, and pollinator seeds to revegetate project disturbed areas. The seed mix can be adjusted to meet local jurisdiction directives and soil conditions once determined. Semi-Desert Loam Revegetation Seed Mixture* Species Pounds per Acre** Number of Seeds*** Western wheatgrass (Pascopyrum smithii) 3.00 8 Indian ricegrass (Achnatherum hymenoides) 2.00 6 Prairie junegrass (Koeleria macrantha) 0.50 26 Sandberg bluegrass (Poa secunda ssp. Sandbergii) 1.00 24 Galleta grass (Pleuraphis jamesii) 2.00 7 Bluebunch wheatgrass (Pseudoroegneria spicata ssp. Spicata) 2.00 6 Bottlebrush squirreltail (Elymus elymoides) 2.00 9 Total 12.50 85 *The seed mix shown is based on existing native grasses that occur in this region. Seed mix may be obtained from other suppliers. ** Pure Live Seed ***Per Square Foot Temporary Use Permit Application Glenwood Springs – Mitchell Creek Electric Transmission Line Rebuild Appendix J: CPW Correspondence Temporary Use Permit Application Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild This page intentionally left blank. 1 Sherman, Amy From:Neumann - DNR, Danielle <danielle.neumann@state.co.us> Sent:Wednesday, September 20, 2023 3:24 PM To:Sherman, Amy; Samantha Canetti - DNR Cc:Chester, Jennifer L; Jay, Braileigh V; Michel, Taylor Subject:Re: Environmental Review Request for the Glenwood Springs–Mitchell Creek Transmission Line Rebuild Project ❚❛❜ CAUTION: This email originated from an external sender. Verify the source before opening links or attachments. ❚❛❜   Hi Amy, We apologize, we thought we responded to this right away in August! Unfortunately, the email accidentally only came to me, and I didn't realize that everyone else wasn't copied. Below is the statement from our district wildlife manager. Please let us know if we can help in any other way. Hi Amy, After reviewing the request there are limited adverse impacts to wildlife resources. Thank you for the detailed letter describing information on avoiding overflights from April 15 to June 30 in production areas and from November 1 to April 30 in the winter range. If you have any further questions please let me know. Sincerely, Sami Canetti, District Wildlife Manager   On Thu, Sep 14, 2023 at 12:12 PM Sherman, Amy <Amy.Sherman@tetratech.com> wrote:  Hello Dani‐     Following up on our request for CPW review of the Glenwood Springs–Mitchell Creek Transmission Line Rebuild  Project. Do you have any updates you can provide?     Thanks much‐        Amy Sherman | Biologist/Project Manager, Rockies Team Lead  Mobile (785) 764-0698 | amy.sherman@tetratech.com Pronouns: she, her, hers Tetra Tech | Complex World, Clear Solutions™ | Science   7222 Commerce Center Drive Ste.150, Colorado Springs, CO 80919 | tetratech.com  2 This message, including any attachments, may include privileged, confidential and/or inside information. Any distribution or use of this communication by anyone other than the intended recipient is strictly prohibited and may be unlawful. If you are not the intended recipient, please notify the sender by replying to this message and then delete it from your system.      From: Sherman, Amy   Sent: Monday, August 21, 2023 12:22 PM  To: Neumann ‐ DNR, Danielle <danielle.neumann@state.co.us>  Cc: Chester, Jennifer L <Jennifer.L.Chester@xcelenergy.com>; Jay, Braileigh V <Braileigh.V.Jay@xcelenergy.com>;  Michel, Taylor <Taylor.Michel@tetratech.com>  Subject: RE: Environmental Review Request for the Glenwood Springs–Mitchell Creek Transmission Line Rebuild Project     Hi Dani‐     Thank you for your response, 9/8 will work just fine for us, thank you. Attached is the requested shapefile.     Appreciate your assistance here as I understand you have quite the workload!     Please let us know if you have any additional questions or requests.     Thanks‐        Amy Sherman | Biologist/Project Manager, Rockies Team Lead  Direct (719) 755-3170 | Mobile (785) 764-0698 | amy.sherman@tetratech.com Pronouns: she, her, hers Tetra Tech | Complex World, Clear Solutions™ | Science   7222 Commerce Center Drive Ste.150, Colorado Springs, CO 80919 | tetratech.com  This message, including any attachments, may include privileged, confidential and/or inside information. Any distribution or use of this communication by anyone other than the intended recipient is strictly prohibited and may be unlawful. If you are not the intended recipient, please notify the sender by replying to this message and then delete it from your system.      From: Neumann ‐ DNR, Danielle <danielle.neumann@state.co.us>   Sent: Friday, August 18, 2023 2:38 PM  To: Sherman, Amy <Amy.Sherman@tetratech.com>  Cc: Chester, Jennifer L <Jennifer.L.Chester@xcelenergy.com>; Jay, Braileigh V <Braileigh.V.Jay@xcelenergy.com>;  Michel, Taylor <Taylor.Michel@tetratech.com>  Subject: Re: Environmental Review Request for the Glenwood Springs–Mitchell Creek Transmission Line Rebuild Project  3    ❚❛❜ CAUTION: This email originated from an external sender. Verify the source before opening links or attachments. ❚❛❜     Also, I would like the shapefile if you can provide it. Thank you for reaching out!     On Fri, Aug 18, 2023 at 2:36 PM Neumann ‐ DNR, Danielle <danielle.neumann@state.co.us> wrote:  Thank you, Amy! We have exceptionally high workloads right now. When is our review due? Is it possible to have a deadline of 9/8/2023?     On Fri, Aug 11, 2023 at 4:04 PM Sherman, Amy <Amy.Sherman@tetratech.com> wrote:  Hello Ms. Neumann –      On behalf of Public Service Company of Colorado, a Colorado corporation conducting business as Xcel Energy, please  see the attached environmental review request for the Glenwood Springs–Mitchell Creek Transmission Line Rebuild  Project located in Garfield County, Colorado.     Please do not hesitate to contact me with any questions or additional information requests. We appreciate your  time, and look forward to your comments.     Thanks much‐     Amy Sherman | Biologist/Project Manager, Rockies Team Lead  Direct (719) 755-3170 | Mobile (785) 764-0698 | amy.sherman@tetratech.com Pronouns: she, her, hers Tetra Tech | Complex World, Clear Solutions™ | Science   7222 Commerce Center Drive Ste.150, Colorado Springs, CO 80919 | tetratech.com  This message, including any attachments, may include privileged, confidential and/or inside information. Any distribution or use of this communication by anyone other than the intended recipient is strictly prohibited and may be unlawful. If you are not the intended recipient, please notify the sender by replying to this message and then delete it from your system.           You don't often get email from danielle.neumann@state.co.us. Learn why this is important   4    ‐‐   Dani Neumann  Land Use Specialist  Northwest Region        To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.   C: 970-366-1223  0088 Wildlife Way Glenwood Springs CO 81601  danielle.neumann@state.co.us | www.cpw.state.co.us      ◉ ◉ ◉ ◉               ‐‐   Dani Neumann  Land Use Specialist  Northwest Region        5 To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.   C: 970-366-1223  0088 Wildlife Way Glenwood Springs CO 81601  danielle.neumann@state.co.us | www.cpw.state.co.us      ◉ ◉ ◉ ◉              ‐‐   Dani Neumann  Land Use Specialist  Northwest Region      To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.  C: 970-366-1223  0088 Wildlife Way Glenwood Springs CO 81601  danielle.neumann@state.co.us | www.cpw.state.co.us     ◉ ◉ ◉ ◉      1800 Larimer Denver, CO 80202 August 11, 2023 Dani Neumann Land Use Specialist Colorado Parks and Wildlife—Northwest Region 0088 Wildlife Way Glenwood Springs, CO 81601 Subject: Environmental Review Request for the Proposed Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild Project in Garfield County, Colorado Dear Ms. Neumann, Public Service Company of Colorado, a Colorado corporation conducting business as Xcel Energy, is proposing to rebuild the 2.25-mile Glenwood Springs to Mitchell Creek 69-kilovolt (kV) transmission line (Project) located in the City of Glenwood Springs and Garfield County, Colorado (Figure 1, attached). The existing transmission line must be rebuilt because it has reached the end of its useful life. The rebuilt transmission line will follow the existing route that connects the Glenwood Springs Substation, located northeast of the Glenwood Hot Springs pool, to the existing Mitchell Creek Substation, located northwest of the Glenwood Meadows shopping center. The Project must cross the Colorado River within the municipal boundary of Glenwood Springs to reach the Mitchell Creek Substation. Construction timing is being evaluated based on helicopter, construction crew, and materials availability as well as pending permit approvals. Grading for transmission line access is anticipated to begin in February 2024 followed by transmission line construction starting in April 2024. Construction activities are anticipated to be completed by Fall 2024. The construction schedule is subject to change as planning is ongoing. A GIS shapefile of Project features can be provided upon request. This letter serves as an update to the letter submitted to Colorado Parks and Wildlife in March of 2022 for the Project. We have reviewed the Colorado Parks and Wildlife (CPW) All Species Activity Mapping Data1, the list of Threatened and Endangered species on the CPW website2, and the U.S. Fish and Wildlife Service Information for Planning and Consultation online tool3, for potentially occurring federally and state-listed species and mapped high priority habitats. Most of the Project is located in developed areas along Interstate 70 that experience human activity and traffic. The 1 CPW All Species Activity Mapping Data. Available online at: https://www.arcgis.com/home/item.html?id=190573c5aba643a0bc058e6f7f0510b7. 2 CPW Threatened and Endangered List. Available online at: https://cpw.state.co.us/learn/Pages/SOC- ThreatenedEndangeredList.aspx. 3 USFWS Information for Planning and Consultation (IPaC) Resource List for the Glenwood Springs-Mitchell Creek Rebuild Project. Online tool is available at: https://ecos.fws.gov/ipac/. 2 Colorado River will be spanned by the Project in its current alignment; no impacts to fishes or riparian areas are anticipated. Trees suitable for raptor nesting within and near the Project have been observed, and raptors may nest near the Project. However, it is likely that raptors nesting near the Project would have a high tolerance for human activity due to the proximity of Interstate 70 and existing development. Bald eagles and other raptors may nest within 0.5 mile of the Project; however, the closest known bald eagle nests are located more than 1 mile west of the Project along the Colorado River. A CPW-mapped bighorn sheep (Ovis canadensis) production area is located north and east of the eastern half of the Project, but does not intersect the Project. The eastern half of the Project also just intersects the southern boundary of a bighorn sheep winter concentration area . As outlined in the CPW Recommendations to Avoid and Minimize Impacts to Wildlife from Land Use Development in Colorado4, we understand that CPW recommends that human activity and overflights be avoided from April 15 to June 30 in production areas and from November 1 to April 30 in the winter range. Along this portion of the line, helicopters must be utilized during construction for pole placement due to limited access, steep terrain, and existing development in the area. Xcel will adhere to disturbance timing restrictions within this portion of the line where feasible, however the Project schedule outlined above has been dictated by the need for replacement of the line in accordance with our Wildfire Mitigation Plan and to avoid service disruptions, and well as the consideration of weather conditions for the safety of construction crews, the helicopter pilot, and the public. In addition, Xcel will be working within the right-of-way of the line, which also lies within and adjacent to active business districts, residential use, highway use, and aerial tram operations that likely influence current behavior and use of the area by bighorn sheep. We are requesting CPW’s Environmental Review feedback regarding state species of concern in the Project area. Thank you for your assistance with this request. Please feel free contact me by telephone at (303) 282-6533 or email at jennifer.l.chester@xcelenergy.com, or please contact our permitting consultant, Amy Sherman, Tetra Tech, Inc., by telephone at (719) 755-3170 or email at amy.sherman@tetratech.com. Sincerely, Jennifer Chester Manager, Siting & Land Rights 1800 Larimer St, Suite 400 Denver, CO, 80202 4 CPW Recommendations to Avoid and Minimize Impacts to Wildlife from Land Use Development in Colorado. May 20, 2020. 5pp. Available online at: https://cpw.state.co.us/Documents/Conservation- Resources/Energy-Mining/CPW_HPH-Map-Layers.pdf. 3 Attachment: Glenwood Springs–Mitchell Creek Electric Transmission Line Rebuild Project—Vicinity Map Glenwood Springs-Mitchell Creek Electric Transmission Line Rebuild Project Figure 1: Vicinity Map c-=:.-=:.J Glenwood Springs City Boundary Existing Electrical Infrastructure ■Substation •Existing Transmission Structure to be Removed Existing Transmission Line Corridor Project Features -Rebuild Route (60-foot ROW) Access Road 0 • • Existing Transmission Structure to Remain Unchanged Preliminary New Transmission Structure Location (Glenwood Springs) Preliminary New Transmission Structure Location (Garfield County) Temporary Construction Easements Helicopter Fly Yard and Materials Staging Area Temporary Construction Easement Construction Method 0 Set by Crane 0 Set by Helicopter 0 8 500 1,000 Feet Scale is 1 :4,500 when printed at 22" x 34" NOT FOR CONSTRUCTION GARFIELD COUNTY � TETRA TECH (},, Xcel Energy" Document Path: R:\Project Warehouse\1_By Circuit\6584 Glenwood-Rifle\MXD\6584_GS_MC_TCE_Fit_Yard_8x11_Exhibit_A.mxdR. Carmody, Siting and Land Rights Temporary Construction Easement Legend !(Pole Location Transmission Line Temporary Construction Easement Transmission Line Easement Parcel Boundary MAPAREA EXHIBIT A O 0 100 Feet FIT, JOZEFAAPN: 218505400065