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HomeMy WebLinkAbout1.0 ApplicationRoaring Fork Water and Sanitation District WASTEWATER TREATMENT FACILITY SITE APPLICATION (REGULATION 22) FOR EXPANSION OF EXISTING DOMESTIC WASTEWATER TREATMENT WORKS OCTOBER 2007 P REPARED BY: SCHMUESER GORD ON MEYER, I NC. 11 8 W . 6rn STREET, SUITE 200 Glenwood Spring s, CO 81601 COLORADO DEPARTMENT OF PUBLlC HEALTH AND ENVIRONMENT Water Quality Control Division 4300 Cherry Creek Drive South Denver, Colorado 80246-1530 (303) 692-3574 APPLJCATION FOR SITE LOCA TJON APPROVAL FOR EXPANSION OF AN EXISTING D01\1ESTIC WASTE\VATER TREATMENT WORKS (Section 22.5, of Regulation No. 22) Applicant: Roaring Fork Water and Sanitation District 945-2144 Address: P.O Box 1002 City, State , Zip: Glenwood Springs, CO 81602 Email Address rfwsd@sopris.net Primary Contact (for project inquiries): Chris Lehrman Consulting Engineer: SGM Address: 118 W. Sixth Street, Suite 200 City, State, ZIP: Glenwood Springs, CO 81601 Email Address chrisL@sgm-inc.com A. Summary of information regarding existing wastewater treatment plant: 1. Existing Location (Legal Description): NEl /4, NEl/4, Section U Township: T7S Range : 89W County: Garfield Lat. 39.451662 Long . -107 .112111 for Wastewater Treatment Works Phone: 970·- Phone: 970-945-1004 Phone:970-945-1004 2. Type and capacity of treatment facility proposed: Extended Aeration -0.214 MGD expansion (0.321 MGD total) Processes Used: Mechanical bar screen for grit removal, Flow measurment, Activated Sludge, secondary clarification, di sinfection, tertiary filtration, aerobic digestion ofbiosolids Hydraulic: 0.321 MGD gal/day (maximum monthly average) Organic: 964 lbs. BOD 5/day Present PE: 1070 Design PE: 3210 % Industrial: 0% 3. Location of Facility: % Domestic: 100% Attach a map of the area , which includes the following: (a) 5-mile radius: all sewage treatment plants, lift stations, and domestic water supply intakes. (b) I-mile radius: habitable buildings , location of public and private potable water wells, and an approximate indication of the topography. 4. Effluent disposal: Surface discharge to watercourse (name) Roaring Fork River -See "other" WQCD-3b (Revised 6/06) Page 1 of 4 Subsurface disposal N I A Land Appl ication N I A Evaporation N I A Other (lis t): Wetlands ad jace nt to th e Roari1rn Fork River -The Di strict is still exp loring the option of being capable to discharge to both the R.F. River and th e wetla nd s depending on th e time of yea r. 5. W hat is th e distance down stream fr om th e di sc harge to th e nea res t domestic water s upply intake? 9 miles Na m e of Supply: City of Glenwood Springs Address of Supply: 806 Coo per, Glenwood Springs, CO 8 1602 What is th e distance down str ea m from th e discharge to the nea res t other point of diversion? 17 miles Na me ofUser: Town of Ne w Castle Address ofUser: P .O . Box 90, New Castle, CO 81647 6. Will a State or Federal gra nt /loan b e sought to finance any portion of this project? No 7. Estimated project cost: $2,000,000 .00 8 . Present z oning of site area? PUD Zoning within a 1-mile radius of s ite -define de s ignation(s)? PUD , Agricultural/Resedential/Rural Density, Agricultural/Industrial, Commercial General, Commercial Limited 9. Who owns the land upon which the facility will be constructed? RFWSD (Please attach copies of the document creating authority in the applicant to construct the proposed facility at this site .) 10 . Who h as the responsibility for operating the proposed facility? RFWSD 11. Who is financially re sp onsible for the construction and operation of the faci l ity? RFWSD 12. Names and addresses of all municipalities and water and/or sa nitation districts within 5-miles downstream of the proposed wastewater tr ea tm ent fa c ility site . No municipal or Di strict WWTFs are located within 5-miles dO\vnstream. The fol lowing are privately owned sys tem s: H-Laz y-F Mobile Home Park , Mountain Meadows MHP, El Rocco MHP (Attach a se parate sheet of paper if necessary) 13 . I s th e facility in a 100-yea r flood pl a in or other natural ha za rd area? No If so , what prec aution s are b eing taken ? None neces sa ry Ha s the flood plain been designated b y the Colorado Water Conse rvation Board, Department of Natural Resources, or WQCD-3b (Revised 6/06) Page 2 of4 other agency? F E MA (Agency Name) If so , what is that de s ig nation ? N / A Plant sit e is abo ve the flood way and flood plain 14. Please identify any a dditional factor s that mi ght he lp the Water Quality Control Divi sion make an informed decision regarding your application for s ite approval. An ex is ting WWTF already exists at thi s site and is functioning well within its discharn.e permit. The original se rvice plan and site appli c ation contemplated this expan sion. (Attach a separate sheet of paper if necessary) B. If the facility will be located on or adjacent to a site that is owned or managed by a federal or state agency, send the agency a copy of this application for the agency's review and recominendation. C. Recommendation of governmental authorities: The application shall be forwarded to the planning agency of the city, town , or county in whosejurisdiction(s) the treatment facility is to be located. The applicant shall obtain , from the appropriate planning agency (agencies), a statement(s) of consistency of the proposal with the local comprehensive plan(s) as they relate to water quality (subject to the provisions of22 .3(6). The application shall be forwarded to the water quality planning agency (agencies) for the area in which the facilities are to be constructed and for the area to be sen1ed by those facilities . The applicant shall obtain, from the appropriate planning agency (agencies), a statement( s) of consistency of the proposal with any adopted water quality management plan( s ). If you have any further cornn1e11ts or questions , please call (303) 692 -3574. I certify that I am familiar with the requirements of the "Site Location and Design Approval Regulations for Domestic \\lastewater Treatment \\I or ks". An engineering report, as described by the regulations, has been prepared and i s enclosed. Date I 0/16/07 Joey Fetzko . District Administrator Typed Name and Title *This form must be signed by the applicant. This form cannot be signed by the Consulting Engineer. Date I. 2 . ~ .). 4. WQCD-3b (Revised 6/06) Recommend Yes Approval No Signature and Title of Representative Managem ent Agency (if different from entities listed below) County (if site is located in an unincorporated area of the County) City or Town (if site is located within 3 miles of the boundaries of a City or Town) Local Health Authority Page 3 of4 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~---~~- ~ D () 9 vJ O" ~ (!) :::. CJ> (!) 0.. °' ---0 ~ N 0 00 "d "' 5 5 [JO )> [JO (!) ::s (") '< ~ • ·~· JO . . ... • '1 I ·-----".:,_ '<.:::); +"--~--;;· 2~i :~'.~-... __ ,ll .. · --t .... ~i.;;7 ., ·,~~ ;>9 ~~'"• ·\._:~;;;;: • -, " ~t; .... r~ , :;--'\. ... . ...-...--. " . . .. _, ---~ . ".i\ \ ~i'i • ,7! '" I ....,_ • \ . " ,.·L · ;,.. . ~"N ·~~ i.;-::-if.~ .. ,, · ... .. -' ; .1 .,.,m:,, . ---. , ::.-·"'l 'XJ• ~c~· "· " ... ' ' .;.r::';' •. ' I ·. " ~ ~ o1o -·-• • -• -· : • . e :,hf;._• • ~., Tl rl . "' f'. 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I ,r"-,., ';(..}: ' • ' ' • ~ ' '<:"' ~ ... ,y ..... • 1 ~' / .r-...... 1 ,,1 ~~ /'!( /..-:.::::. -·· . ~tl!trc Lc _L, ... =~'.~ _:i':::: '/. :, ~. · 1 1\ \ , : .'"1':7..1_~ ~ ;~ ... ;,rf ·.::' ·: . 1 " '-·~~:.::~ ,; ~ • 0 • .7 i·'@\ 1 f ... 'IP·:. ..... ,: y ._::., " ~ ~ 6 SCHMUESER I GORDON I MEYE I 18 W. 6TH STREET, SUITE 200 -R GLENWOOD SPRINGS, COLORADO 8 I 60 I "-= --::-:-:--::-::--:-'.:-=:-::---~------__!._:_:_=.::..=:_: <970> 945· I 004 FAX (970> 945-5948 E N G I N E E Rs I s u R v E y 0 R s ASPEN , COLORADO (970> 925-6727 CRESTED BUTTE , CO (970) 349-5355 • • 6 SCHMUESER ENG NEERS GORDON MEYER N 1'. <;URVEYORS I I 8 W . 6TH. SUITE 200 P .O . BOX 2 I 55 P .O . BOX 3088 GLEN'MXXl SPRINGS, = 8 I 60 I ASPE N, CO 8 I 6 I 2 CRESTED BUTTE. CO 8 I 22 4 October 18, 2007 970-945-1 004 970-925-6727 970-349-5355 FX : 970-945-5948 FX : 970-925-4 I 57 FX : 970-349-5358 Fred Jarman Garfield County Planner 108 8th Street Suite 201 Glenwood Springs, CO 81601 RE: RFWSD -Site Application for an expansion of an existing domestic wastewater treatment works Dear Mr. Jarman : Enclosed you will find four copies of CDPHE Regulation 22 (Site Application) submitted on behalf of the Roaring Fork Water and Sanitation District (District) for a proposed expansion to the existing wastewater treatment facility . The previously approved site application is number 4133 and the discharge permit is CDS permit number C0-0044750. Garfield County is required to review and comment on this application. One copy is for you to keep and I will pickup the other three copies when they are signed . By way of history, the RFWSD was created in 1994 as the regional water and wastewater provider to serve the Aspen Glen P.U.D. and the surrounding developments. The District has an approved service plan on file with the County. The existing WWTF is a 0.107 million gallons per day (MGD) activated sludge fac ility with tertiary filtration followed by discharge to a natural wetland . The WWTF was master planned to be built in three phases of 0 .107 MGD, to a build out of 0 .321 MGD. The District has been experiencing growth consistent with the service plan approved by Garfield County and with the P.U .D.s approved by Garfield County in this area. The District has decided , because of the growth and the increase in construction costs, to build the last two phases of the WWTF as one phase. The District is planning on having the new expansion under construction by the fall of 2008 . Thank you in advance for your time and if you have any questions or if you would like an electronic copy of this report in PDF format , please call or e-mail : chrisL@sgm-inc.com. Sincerely , SCHMUESER GORDON MEYER, INC. q,~ Chris Lehrman, E. I. Design Engineer Enclosures : (4) RFWSD Regulation 22 Cc: RFWSD Staff ~:~~~ Louis 0. Meyer, P.E. Project Engineer OCT 1 9 200 7 ' • 1:11996196059\A-82 VWJTF Expansion Planning\2 -VWJTF Expansion Pennittingll 20071018 Fred Jannan.doc Roaring Fork Water and Sanitation District WASTEWATER TREATMENT FACILITY SITE APPLICATION (REGULATION 22) FOR EXPANSION OF EXISTING DOMESTIC WASTEWATER TREATMENT WORKS OCTOBER 2007 PREPARED BY: SCHMUESER GORDON MEYER, I NC. 11 8 W. C'' STREET, SUITE 200 Glenwood Spri ng s, CO 81601 ~ • • SITE APPLJCATJON COJ\1PLETENESS CHECKLIST Expansion of an Existing Domestic 'Vastewater Treatment 'Vorks Name of Project: Applicant Name and A.ddress: Consultant Name and Address: Type of Project: Section Elements 22 .5(1) Application submitted o~ proper form. Signatures from local authorities and planning agencies. Signed by responsible party of the proposed facility 22.5(2) Engineering Report 22.5(2)(a) Changes to existing service area and population Loading projections. 22 .5(2){b) I PELs developed in coordination with the Division. 22 .5(2)(c) I Analysis of the of the existing treatment works. 22 .5(2)(d) I Analysis of alternatives Consolidation alternatives recommended 22.5(2)(e) I Changes in the financial system 22 .5(2)(f) I Implementation plans and schedule. Estimated construction time Estimated date on which the plant will be in operation . 22 .5(3) Soils Report stating that the site will support the facility . 22.5(4)(a) I Re view comments by the management agency if necessary Regulation No. 22 Guidance Document Page 50 of 70 Please indicate where (document and page#) the submittal addresses the following ~ 22.5(4)(b) Review comm ents by the cou nt y if necessary 22 .5(4)(c) Review comm ents by the ci ty or town if ne cessa ry 22.5(4)(d) Rev iew comme nts by the loca l hea lth auth orit y. 22 .5(4)(e) Review commen ts by th e wa ter qua lit y planning age ncy. ect\ ()() 22.) IZ ~ ' Regulat ion No . 22 Guidance Document Page 51 of 70 • • • Table of Contents Engineering Report Executive Summary ................................................................................. 2 22.5(1) Application submitted on proper fonn ......................................................................... 3 22.5(2) Engineering Report ...................................................................................................... 4 22.5(2)(a) Service Area ......................................................................................................... 4 22.5(2)(b) Preliminary Effluent Limitations ......................................................................... 5 22.5(2)(c) Analysis of existing treatment works ................................................................... 6 22.5(2)( d) Consolidation analysis ......................................................................................... 7 22.5(2)(e) Financial capability .............................................................................................. 8 22.5(2)(f) Schedule ............................................................................................................... 9 22.5(3) Soils Report ................................................................................................................ 11 22.5(4) Review by other agencies ........................................................................................... 12 22.5(4)(a) Review comments by the management agency if necessary ............................. 12 22.5(4)(b) Review comments by the county if necessary ................................................... 12 22.5(4)(c) Review comments by the city or town if necessary ........................................... 12 22.5(4)(d) Review comments by the local health authority ................................................ 12 22.5(4)(e) Review comments by the water quality planning agency .................................. 12 1:\1996 \96059 \A-82 WWTF Expansion Plannin g\2 -WWTF Expan s io n Permittin g\Re g 22 Fina l.doc Page l of 12 • • • Engineering Report Executive Summary The Roaring Fork Water and Sanitation District is submitting this application to allow for the construction of an expansion to the existing wastewater treatment facility . This report follows the outline and guidelines of the "Regulation No. 22" guidance document (Site Application). This executive summary will provide a brief description of the key points in the document. 1. The District currently owns and operates a 0 .107 million gallons per day (MGD) activated sludge facility with tertiary filtration. The facility was designed in 1994 and was planned to have three phases totaling 0.321 MGD at build out. Currently, the WWTF is experiencing flows in the range of 55% of capacity and is meeting the discharge limits . The District does not have an inflow or infiltration problem. 2. The District has been experiencing an accelerated growth rate due to the shortage of housing and housing developments trying to satisfy that demand in the region . In 2007 , the District experienced a 15% per year growth rate. The growth rate is projected to continue at the same rate or higher for the next several years . 3. The construction costs in the region have also have had an accelerated growth of upwards of 25% per year. The growth has been attributed to the high cost of living, labor shortage, and the abundance of construction projects in the region . 4 . The District has decided to build the WWTF to the full build out of 0.321 MGD because of both the growth rate of the District and the increased construction costs. The Board of Directors feels like the accelerated growth rate will continue and construction costs will only go up , so it would be prudent to build the rest of the planned WWTF while the District is in a very good financial situation . 1:\1996\96059\A -82 WWTF Ex pa ns ion Plannin g\2 -WWTF Ex pansio n Permittin g\Reg 22 Fin al.doc Page 2 of12 • • • 22 .5(2) Engineering Report 22.5(2)(a) Service Area The current service area for the District includes the developments of Aspen Glen , Coryell Ranch, Midland Point, and IronBridge, all of which are located along Garfield County Road 109 and the Roaring Fork River. The projected service area will consist of the current service area plus the area on the east side of the Roaring Fork River expanding from the north on the east side of HWY 82 at the CMC intersection to the south on the east side of HWY 82 at the Cattle Creek Intersection. Presently, this area is being served by ISDS systems and small package plants . The District's service area is shown in the attached map labeled figure 1. The current population of the District is roughly 440 house hold equivalents (EQRs) with flows to the WWTF at roughly 59 ,000 gallons per day (GPD). The flows to the WWTF have been much lower than industry standards with around 130 gallons per EQR per day. The traditional industry standards are 350 gallons per EQR per day . The low flows can be explained by the high amount of second home ownership in the District and also by the high number of homes that are under construction and are not being lived in. In the projections that have been done for the District, these historical low flows were accounted for so that the WWTF was not over designed. Trends will change to much higher flows. The higher flows can be explained by more first home owners living and working in the region and the construction of the homes being completed with people moving into them. A population and loading projection study is attached as figure 2 . The growth in the district can be explained because the existing developments are roughly 30% built and they are seeing rapid growth due to the real estate values in the county. In 2007, the District has seen a 15% per year growth rate and it has been forecasted to have as much growth or more in 2008 . The District is also receiv ing preliminary requests for water and waste water service from areas in the projected service area that are not currentl y being served. In the past, these developments have not been able consolidate with the District because of the high cost of installing infrastructure to the District's facilities . 1n the future , the District is anticipating several new developments that will have the capital to extend the required infrastructure which will enable these smaller developments to connect. When the new developments are approved and begin building homes , it will accelerate the growth rate even more. On top of that , once the infrastructure is installed to their property lines , the District anticipates that several of the smaller developments wi ll connect at that t ime . 1:\19 96\96059\A -82 WW TF Expans io n Pl annin g\2 -WWTF Expans ion Permit t in g\Reg 22 Fin a l.d oc Pa ge 4of12 • • RFWSD WWTF Expansion Planning • Actual Development Plans -. ---------·-. -·-----·--. ·-------•vv vv IVu;.111 -.... u ..... lt,;lllllWll Bair Mountain Western Wayne Misc Infill Use (80 Total Aspen Glen (7% Crystal River Coryell (5% West Chase Midway Teller Cattle Creek Meadows Mobile Rudd/Cattle (1% per Gal/Day) Adjusted Year Growth Rate) Ranch Growth Rate) CMC Turnoff Carbondale Burry Ranch lronBridQe Area H Lazv F SorinQs Intersection MHP Gravel Pit Creek Year) EQRs MGD EQRs MGD Use MGD Year 2007 262 0 30 0 0 0 145 0 0 0 0 4.4 441.4 0 .132 262 .0 0 .0210 0 .074771 2007 2008 280 .3 0 31 .5 1 0 0 195 0 0 0 0 5.1 512 .9 0.154 280 .3 0 .0224 0.092201 2008 2009 300 .0 0 33 .1 2 0 0 225 0 0 0 0 5.6 565 .6 0.170 300 .0 0 .0240 0 .1037 2009 2010 321 .0 0 34 .7 3 0 0 255 0 0 0 0 0 6 .1 619 .8 0.186 321 .0 0 .0257 0.115337 2010 2011 343.4 0 36 .5 0 4 0 0 285 0 0 0 0 0 0 6.7 675.6 0.203 343.4 0.0275 0.127121 2011 2012 ~ 367 .5 0 38 .3 ' 0 ~ 5 0 30 315 0 0 0 0 0 0 7.6 763 .3 0.229 367 .5 0 .0294 0.148151 2012 2013 393 .2 0 40 .2 0 6 0 60 325 30 0 10 0 0 0 8.6 873.0 0.262 393 .2 0 .0315 0.175409 2013 2014 420 .7 0 42 .2 40 7 0 90 325 60 0 20 0 0 0 10.0 1015.0 0.304 420.7 0 .0337 0.211936 2014 2015 450 .2 0 44 .3 80 8 0 120 325 90 0 30 0 0 0 11 .5 1159.0 0.348 450 .2 0 .0360 0.248653 2015 2016 481 .7 0 46 .5 120 9 0 150 325 120 0 40 0 0 0 12 .9 1305 .1 0.392 481 .7 0 .0385 0.285573 2016 g 2017 ~ 515.4 of'~ 0 ~ 48 .9 \i.1. 160 10 0 180 ' 325 122 0 . 0 50 0 30 0 14.4 1455.7 0.437 515.4 0 .0412 0.323315 2017 2018 551 .5 0 51 .3 200 11 0 210 325 122 0 0 50 0 60 0 15 .8 1596.6 0.479 551.5 0.0441 0.357653 2018 2019 590 .1 0 53 .9 200 12 0 240 325 122 0 0 50 0 90 0 16 .8 1699.8 0.510 590.1 0.0472 0.380117 2019 2020 631.4 0 56 .6 200 13 0 270 325 122 0 0 50 0 120 0 17 .9 1805.8 0.542 631.4 0 .0505 0.402845 2020 2021 643 .0 0 59.4 200 14 0 300 325 122 0 0 50 0 150 0 18.6 1882.0 0.565 643 .0 0 .0514 0.42315 2021 2022 1¥Cl 643 .0 Ill~ ~ 0 i 62.4 •n1 200 15 0 330 325 122 0 0 50 0 150 0 19 .0 1916 .3 0.575 643 .0 0 .0514 0.433442 2022 2023 643 .0 0 65 .5 200 16 0 360 325 122 0 0 50 0 150 0 19 .3 1950.8 0.585 643 .0 0.0514 0 .44378 2023 2024 643 .0 0 68 .8 200 17 0 390 325 122 0 0 50 0 150 0 19 .7 1985.4 0.596 643 .0 0.0514 0.454165 2024 2025 643 .0 0 72 .2 200 18 0 400 325 122 0 0 50 0 150 0 19 .8 2000 .0 0.600 643 .0 0.0514 0.45854 2025 2026 643 .0 0 75 .8 200 18 0 400 325 122 0 0 50 0 150 0 19 .8 2003.6 0.601 643 .0 0 .0514 0.459634 2026 ~l 2027 'E!!\1 643 .0 ~,..~ .... 0 ~ ~"'II 79 .6 ~ 200 D 18 0 400 g 325 122 ~ 0 ,_ 0 50 0 150 -0 19 .9 2007.5 0.602 643 .0 0.0514 0.460782 2027 2028 643 .0 0 80 .0 200 18 0 400 325 122 0 0 50 0 150 0 19 .9 2007 .9 0.602 643 .0 0.0514 0.460904 2028 • • 1:11996196059\A-82 Wl/l/TF Expansion Planningl1 -Wl/l/TF System StudylUltimate Buildout.xls 10/4/2007 Figure 2 • • • 22.5(2)(b) Prelim inary Effluent Limita ti ons The Proposed effluent limitations (PELs) are attached. The PEL number is 200229. Date of PE Ls The date of the PELs is July 12, 2007 . 1:\1996\96059 \A-82 WWTF Ex pans ion Plannin g\2 -WWTF Expansion Permittin g\Re g 22 Final.doc Page 5of12 ' • • STATE OF COLORADO Bill Ritter, Jr., Governor James B. Martin, Executive Director Dedicated to protecting and improv ing the health and environment of the people of Colorado 4300 Cherry Creek Dr. S. Laboratory Services Division Denver, Colorado 80246-1530 8100 Lowry Blvd. Phone (303) 692-2000 Denver, Colorado 80230-6928 TDD Line (303) 691-7700 (303) 692-3090 Located in Glendale, Colorado http://www.cdphe .state.co.us July 12, 2007 Christine A. Bechtel, EI Schmueser Gordon Meyer 118 W. Sixth Street, Suite 200 Glenwood Springs, CO 81601 ""~,,,. '"!' ,'1-('f! '•p . , . -'r.rlt/J •..! •/ I~ . vo; ,..~., ._, ... ,.. . :-- ' . Re: PEL-200229, Roaring Fork Water and Sanitation District WWTF Dear Ms. Bechtel: Colorado Department of Public Health and Environment The Water Quality Control Division (Division) of the Colorado Department of Public Health and Environment has prepared, per your request, the Preliminary Effluent Limits (PELs) for the rehabilitation and expansion of the Roaring Fork Water and Sanitation District wastewater treatment facility (WWTF). These effluent limits were developed, as detailed in the attached document, for use as one of the submittals in your application for Site Approval. PELs developed for the WWTF (Tables 1 and 2) are based on effluent limits for pollutants of concern as established in the Regulations for Ejjluent Limitations (Regulation No. 62), and water quality-based effluent limits (see the analysis in the attached document) necessary for protection of the water quality in the receiving water. With a hydraulic design capacity of 0.32lmillion gallons per day (MGD) and discharge either to wetlands or to the Roaring Fork River, both of which are identified as stream segment COUCRF03a, the Roaring Fork W &SD WWTF may require an individual pennit, depending on the discharge location. The total ammonia limits warrant clarification. As explained in the attached document, the total ammonia water quality-based effluent limits (WQBELs) are based on assumptions, given the absence of adequate effluent and in-stream pH and temperature data. This is done per Division standard procedure and utilizes statistically determined in-stream and effluent pH and temperature conditions for various types of facilities as inputs to the Ammonia Toxicity (AMMTOX) Model. • • • Table 1 Proposed Roaring Fork W&SD WWTF Expansion Preliminary Effluent Limits for Discharge to the Roaring Fork River BOD5 (mg/I) 45 (7-day average), 30 (30-day average) BOD5 (% removal) 85 (30-day average) TSS, mechanical plant (mg/I) 45 (7-day average), 30 (30-day average) TSS , mechanical plant (% removal) 85 (30-day average) Oil and Grease (mg/1) 10 (maximum) pH (s .u.) 6.5-9.Q (minimum-maximum) .. ,, .,c;,;;,J'>'"''Qil~~r'foiii11i'xL >~'•·'·: :): .:<<':>.:·•·•·.·. , i ::.~~·::.::>:.:: ... ::.=::.~:~·;.:::,:::·~" ">. .::;:_}.. 1 • .... ~ ~~· /_:;·, ,·.:: :.,,: '.';:;;. :._·::·:::.·:: :: •• :;:·._·.;:·: Vi :.x L'M'4~'<:_d"P4FWQ.ifkt@i'Q"t!°d(fi.;11liioli /··•··., .. , .... Fecal Coliform (#/100 ml) 12 ,000 (7-day geomean), 6,000 (30-day geomean) E. coli ( #1100 ml) 4,000 (7-day geomean), 2,000 (30-day geomean) Total Residual Chlorine (mg /I) 0.5 (daily maximum), Report (30-day average) Monthly Total Ammonia , Jan . -Dec . (mg/1) Report (daily maximum), Report (30-day average) ·.:·: ;'· Table 2 .. .. .. ·.•.·· ... · .•.. ··,. · ..•. ·.•··· .. · Proposed Roaring Fork W&SD WWfF Expansion : > Prelimiriary Effluent Limits for Discharge to the Tributary Wetlands !BODs (mg/l) 45 (7-day average), 30 (30-day average) IBOD 5 (%removal) 85 (30-day average) frSS , mechanical plant (mg/I) 45 (7-day average), 30 (30-day average) rrss, mechanical plant (% removal) 85 (30-day average) Pi! and Grease (mg/I) J 0 (maximwn) tpH (s.u.) 6.5-9.0 (rninimwn-maximum) ·" Other Pollutants WQBELs !Fecal Coliform (#/100 ml) 400 (7-dav geomean), 200 (30-dav geomean) E. coli (#II 00 ml) 252 (7-dav geomean), 126 (30-dav geomean) Total Residual Chlorine (mg/l) 0.019 ( dailv maximum), 0 .011 (30-dav average) .·: ... Monthly Total Ammonia WOBELs AD BA Cs NI Ls anuarv (mg/I) 19 (daily maximmn), 5.6 (30-day average) 3.8 (2-vr average) 3.4 (30-day average) IFebruarv (mg/l) 19 (daily maximum), 5 .6 (30-day average) 2 .9 (2-vr average) 3.4 (30-day average) !March (mg/I) l 8 (dailv maximum), 5.4 (30-dav average) i 3 .1 (2-vr average) 3.4 (30-dav average) !April (mg/I) 18 (daily maximum), 5.4 (30-day average) 3.7 (2-vr averal!e) 2 .0 (30-dav average) !M.av (mg /I) J 8 (daily maximum), 5.5 (30-dav average) 2.8 (2-vr averai?e) 2.0 (30-dav average) !June (mg /J) 19 (daily maximum), 5. J (30-dav average) 1.8 (2-vr average) 2.0 (30-dav average) !July (mg/l) 19 (daily maximum), 4.4 (30-dav average) 3.4 (2 -vr average) 2.0 (30-dav average) [August (mg/I) 22 (daily maximum), 4. 7 (30-dav average) 2 .5 (2-vr average) 2 .0 (30-dav average) September (m g/I) 20 (daily maximum), 4 .6 (30-dav average) 3.2 (2-vr average) 2 .0 (30-dav average) October ( mg il) 19 (daily maximum), 5.0 (30-dav average) 3.2 (2-vr average) 3.4 (30-dav average) !November (mg/I) 18 (daily maximum), 5.5 (30-dav average) 2 .3 (2-vr average) 3.4 (30-dav average) tDecember (m g/l) 18 (daily maximum), 5.4 (30-dav average) 2 .8 (2-vr average) 3.4 (30-dav average) Additionally, since the receiving water is subject to antidegradation-based effluent limits, two- vear rolling-average limits have been detennined for discharges to the wetlands (note that antidegradation-based effluent limits did not apply to discharges directly to the Roaring Fork River); for ammonia. These are presented under ADBACs in Table 2. In effect, only the 2 • • • assimilative capacity limits apply until sufficient effluent data (two cycles) are collected to report the rolling average. Thus, the facility is expected to meet the ADBACs after two years of operation. The proposed facility may elect, as an alternative to AD BA Cs, continuing with the existing effluent mass loading to the receiving water. These limitations are called Non-Impact Limits (NIL). The maximum pounds of ammonia in the effluent are limited to the currently limited load based on the current concentration limit and the current design flow; or, where ammonia limits have not been established, the maximum historic, monthly concentration in the effluent, referred to as the implicit limit, at the current design flow. These mass values are then translated to NILs, by talcing the mass divided by the proposed design flow. If you have any questions regarding this matter, please contact me 'at (303) 692-3608. Sincerely, Ar Eric T. Oppelt, P.E. CDPH&E, WQCD cc: Kent Kuster, WQCD -Engineering Section Mark Kadnuck, WQCD -Engineering Section PEL-200229 file 3 • • • Roaring F ork WSD WWTF Preliminary Effluent Limits PEL-200229 Name of Facility PEL Number WBID -Stream Segment Classifications Designation PRELlMINARY EFFLUENT LIMITS, APPENDIX A THE ROARING FORK RIVER ROARING FORK \V &SD \VWTF Table A-1 Assessment Summary Roaring Fork W&SD WWTF •' PEL-200229 Upper Colorado River Basin, Roaring Fork River Sub-basin, Stream Segment 03a: Main stern of the Roaring Fork River, including all tributaries and wetlands, from a point immediately below the confluence with Hunter Creek, to the confluence with the Colorado River except for those tributaries included in Segment l and specific listings in Segments 3b through 10. COUCRF03a Cold Water Aquatic Life Class 1 Class 1 a Existing Primary Contact Recreation Agriculture Water Supply Undesignated I. Introduction The preliminary effluent limits (PELs) evaluation for the Roaring Fork Water and Sanitation District (W&SD) Wastewater Treatment Facility (WWTF), hereafter referred to as the Roaring Fork W&SD WWTF, was developed for the Colorado Department of Public Health and Environment (CDPHE) Water Quality Control Division (Division). The evaluation was conducted to facilitate issuance of PELs for the Roaring Fork W &SD WWTF for pollutants found to be of concern. Figure A -1 contains a map of the study area evaluated as part of PELs development. The Roaring Fork W &SD WWTF is located in Garfield County, approximately five miles north of Carbondale, Colorado. The Roaring Fork W &SD WWTF currently discharges to wetlands that are adjacent to the WWTF and considered to be tributary to the Roaring Fork River (and hereafter referred to as the "T1ibutary Wetlands"). In addition to a proposed expansion in hydraulic capacity, the facility also is considering adding a discharge point directly to the Roaring Fork River. This PEL will assess discharges to both potential receiving waters at the proposed hydraulic capacity of 0.321 MGD (0.50 cfs). For discharge to the Roaring Fork River, the ratio of the low flow of the Roaring Fork River to the proposed Roaring Fork W &SD WWTF de sign flow is 270: 1. The nearest upstream and downstream facilities had no impact on the assimilative capacities available to the Roaring Fork W &SD WWTF. Analyses thus indicate that as similative capacities of the Roaring Fork River are very large . PELs Appendix A Page 1 of 21 Last Revised by EO July 8, 2007 • • • Roaring Fork WSD WWTF Preli minary Effluent Limits ,../ \~ l Figure A-1 Study Area .:... ... 1~--::::t.r't r~1): .. _. ~--\ -Gl ·e~wo-Ci<LS'pr i0gs \ '< 1~?~ ) -: __ ,,._ r-4 ' t \ ... __ ·I -:,: , ;·· ; ) I # ~/=~/ ',, r . \ \i ~,L r Di,faio~ration \~;r.,.,. k ,;,,--·--~ --, I . .-/ UL~ Cattlel Cree ; .-.. ( .• ,. ___ .... -·· i I f j .~"-·~-----·~ Ro'.nng ,ii"' w~n ~WfF \:-~~°"'"(!:'' Rim ! -'~ .. k ·-; '.'"'-.. ~--<:-........ ,/~ ~ I ' " Y. "\ " ,.. .......... ,:-"'• f, .Crystal River-+'_i~!_' ·...:.... _______ -----.,.. •El ~ebel ·----·-----------i '.· 'boodale --.. ; ~ ,, ,x, -;; ~ _I __ . \:~ • _/,.. USGs Gage Station 09 LEGEND PEL-200229 r·'""·'>, -.. -state -County ~ Lake/Pon-0/0cean -Expressway Mi I l tary Area $t%~ii0! Hat Iona I Park ~Other Park c-1 City -county Source: US Census Bureau, Tiger Map Server -Highl'$Y -Connector ~ Stream 0 2 4 6 a "i i I ! . I I sea 1 e 1: 216103 0 1i 14 16 16 110 l<.tii :t.awrN.fi!'--tr12 scale deneoos: on 11>00itor resolution • WWTF Discharge Location -tr Water Quality Sampling Station • Flow Gage Station For continued discharge to the Tributary Wetlands, it is the Division's standard procedure to assume, absent a mixing zone study, that the low flow of a wetland is zero. Thus, for purposes of this PELs analysis, the low flow is assumed to be zero. The Roaring Fork WWTF is the sole known point source contributor to this wetland. No other point sources were identified as dischargers to the wetlands. Thus, the findings of this assessment indicate that there is no di1ution, no other sources of pollutants of concern, and that assimilative capacities are equal to the in-stream standards applied to the Roaring Fork WWTF effluent discharge. Information used in this assessment includes data gathered from the Roaring Fork W &SD WWTF, the Division, the Colorado Division of Water Resources (DWR), the U.S. Environmental Protection Agency (EPA), the U.S. Geological Survey (USGS), the U.S . Census Bureau and com1mmications with the local water commissioner. The data used in the assessment consist of the best information available at the time of preparation of this PELs analysis . PELs Appendix A Page 2of21 Last Revised by EO July 8, 2007 • • • Roaiing Fork WSD WWTF Preliminary Effluent Limits PEL-200229 II. \Vater Quality The Roaring Fork W &SD WWTF discharges to the Water Body Identification (WBID) stream segment COUCRF03a, which means the Upper Colorado River Basin, Roaring Fork River Sub- basin, Stream Segment 03a. This segment is composed of the "Mainstem of the Roaring Fork River, including all tributaries and wetlands, from a point immediately below the confluence with Hunter Creek, to the confluence with the Colorado River except for those tributaries included in Segment 1 and specific listings in Segments 3b through 1 O." Stream segrrient COUCRF03a is classified for Cold Water Aquatic Life Class 1, Class 1 a Existing Primary Contact Recreation, Water Supply and Agriculture. Statewide Basic Standards have been developed in Section 31.11 (2) and (3) of The Basic Standards and Methodologies for Swface Water to protect the waters of the state from radionuclides and organic chemicals. In Section 31.11 (1) of the regulations, narrative standards are applied to any pollutant of concern, even where there is no numeric standard for that pollutant. Waters of the state shall be "free from harmful substances in harmful amounts." Total dissolved so]jds (TDS), and sediment are such pollutants of concern being discussed by Agricultural and Water Quality Standards workgroups. In order to protect the Basic Standards in waters of the state, effluent limitations with monitoring, or "monitoring only" requirements for radionuclides, organics, TDS, or any parameter of concern could be put in CDPS discharge permits. Numeric standards are developed on a basin-specific basis and are adopted for particular stream segments by the Water Quality Control Commission . To simplify the listing of the segment-specific standards, many of the aquatic life standards are contained in a table at the beginning of each chapter of the regulations. The standards in Table A-2 have been assigned to stream segment COUCRF03a in accordance with the Classifications and Numeric Standardsfor Upper Colorado River Basin and North Platte River (Planning Region 12). Note that the tem1s of and associated values that correspond to TVS and WS are further explained in the regulations . Except for ammonia, those pollutants with TVS-based and WS-based standards are not applicable to this facility and therefore no further discussion is provided as part of this analysis; ammonia is discussed further in Section IV of this analysis. Ambient Water Qualitv for the Roaring Fork River The Division evaluates ambient water quality based on a variety of statistical methods as prescribed in Section 3 l.8(2)(a)(i) and 3 I.8(2)(b )(i)(B) of the Colorado Department of Public Health and Environment Water Quality Control Commission Regulation No . 31. Ambient water quality is evaluated in this WQA analysis for use in detennining assimi lative capacities. To conduct an assessment of the ambient water quality upstream of the Roaring Fork W &SD WWTF, data were gathered from Division Station 12702 (Roaring Fork River below Confluence with Cattle Creek), located approximately 3 miles downstream from the facility . Data were limited to two data points collected in May 1998 and February 1999. Note that although these data are based on samples collected at downstream locations, they are comparable to data representative of PELs Appendix A Page 3of21 Last Revised by EO July 8, 2007 ' • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 upstream water quality . A summary of these data is presented in Error! Ref ere nee source not found .. Table A-2 In-stream Standards for Stream Segment COUCRF03a 1 :.j;k:~·c;) ,., .. · ,,(;{:{;;;; ···· . ' ' ''1Y/Y· ........... (ffi1dBiqtii.,;;:,:;; -. ... ····· ····•···.7'.i'.:\'.'fo//!:ii)\.••.••.•//'.·.J/('..?Y -...... .... ..... ,.., •• , .•.•.• ,. ··-··· . . .. ".Y e'-'~ ... ,~, .. --"',:. .. .. Dissolved Oxygen (DO)= 6 mg /I, minimum(7 mg /l, minimum during spawning) pH =6.5-9 SU Fecal Coliform chronic = 200 colonies /100 ml E coli chronic= 126 colonies/JOO ml ~ .,, '''"'''"'''ZHNYUi:'; "·•"'' 5.:··.,.,n •• :•c:.:. .··.·· ·{'ff'L'YY\Li> >.<.2•·· ··•.'.•·'··.·•><.• ··-· '6 ..... • .., ......... ., .... Un-ionized annno nia acute and chronic = TVS Chlorine acute = 0.019 mg /I Chlorine chronic= 0.011 mg /I Free Cyanide acute= 0.005 mg/I Sulfide chronic= 0 .002 mg/I Boron chronic= 0.75 mg/I Nitrite acute= 0.05 mg /1 Nitrate acute = 10 mg/l Chloride chronic= 250 mg/I Sulfate chronic= WS ,_.,...,,, ... """ ·~~,. 1111.vi iil.<.'.l!;!J:.9/.(;j(flh ''•·':w·'·=·: '!Ol:H;S..·x.•••'.ii'. (.•/!\'·-.-;/ !i·•· i / .• ·.• ii'•·•i.···•.·c····· .... -~:'""""' Total Recoverable Arsenic acute= 50 µg /l Dis solved Cadmium acute for trout and Dissolved Cadmium chronic= TVS Total Recoverable Trivalent Chromium acute= 50 µg/l Dissolved Hexavalent Chromium acute and chronic =TVS Di ssolved Copper acute and chronic= TVS Dissolved Iron chronic = WS Total Recoverable Iron chronic= 1000 µg /l Di ss olved Lead acute and chronic= TVS Dissolved Manganese chronic =WS Dissolved Manganese acute and chronic =TVS Total Mercury chronic = 0 .01 µg/l Dissolved Nickel acute and chronic= TVS Dissolved Selenium acute and chronic =TVS Dissolved Silver acute and Dissolved Silver chronic for trout = TVS Dissolved Zinc acute and chronic= TVS PELs Appendix A Page 4of21 Last Revised by EO July 8, 2007 • • • Roaiing Fork WSD WWTF Preliminary Effluent Limits PEL-200229 Table -A-3 Temp (0 C) 2 7.9 8.8 9.6 8.8 20 pH (su) 2 8.2 8.4 ,•' 8.6 8.4 6.5-9 Fecal Co lifonn (#/I 00 ml) 2 83 113 142 104 200 NH3 , Tot (mg/I) 2 0.011 0.035 0 .060 0.035 NA 2 Note J: The calculat e d mean is the geometric mean. Note that for s ummari zation purposes, the value of one was used where there :was no detectable amount because the geo metric mean cannot be calculated using a value e qual to zero. No t e 2: When sample results were be low detect ion levels, the value of zi:ro was used in accordance with the Division's standard approach for summarization and averaging purpo ses. Ambient Water Quality for the Tributary Wetlands The Division evaluates ambi ent water quality based on a variety of statistical methods as prescribed in Section 31.8(2)(a)(i) and 31.8(2)(b)(i)(B) of the Colorado Department of Public Health and Environment Water Quality Control Commission Regulation No. 31. The ambient water quality was not assessed for the Wetlands Tributary because the background in-stream low flow condition is zero, and because no ambient water quality data would exist at this low flow . III. Water Quantity The Colorado Regulations specify the use of low flow conditions when establishing water quality based effluent limitations, specifically the acute and chronic low flows. The acute low flow, referred to as 1E3, represents the one-day low flow recurring in a three-year interval. The chronic low flow, 30E3, represents the 30-day average low flow recurring in a three-year interval. Low Flow Analvsis for Discharge to the Roaring Fork River To determine the low flows available to the Roaring Fork W &SD WWTF, USGS Gage Station 09081000 (Roaiing Fork River Near Emma, CO) located upstream from the facility was used. This gage station provides a conservative analysis of the low flows available to the Roaring Fork W &SD WWTF because several tributaiies contribute flow to the Roaring Fork River between the gage station and the Roaring Fork W &SD WWTF point of discharge. The local Water Commissioner confirmed that although there are ten "diversions of significance" between USGS Gage Station 09081000 and the facility, inflow from the Crystal River, alone, would contribute more than the ten major diversions take out. Thus, using the upstream gage without correction results is a conservative estimate of the low flows available to the Roaring Fork W &SD WWTF. A conservative analysis is adequate for this PELs study because the process required to subtract and to add in the various diversions and inflows to reflect the actual low flow available to the facility would be resource intensive and would not change the outcome of this analysis . PELs Appendix A Page 5 of21 Last Revised by EO July 8, 2007 • • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 Daily flows from the USGS Gage Station 09081000 were obtained and the ammal 1E3 and 30E3 low flows were calculated using U.S. Environmental Protection Agency (EPA) DFLOW software. The output from DFLOW also provides calculated acute and chronic low flows for each month. Flow data from March 12, 1998 through September 30, 2006 were available from the gage station. The gage station and tirn~ frames were deemed the most accurate and representative of current Dows and were therefore used in this analysis. Based on the low flow analysis described previously, the upstream low flows available to the Roaring Fork W &SD WWTF were calculated and are presented in Table A-4. IE3 Acute 30E3 Cluonic 135 135 Table A-4 141 I 135 I 153 I 174 I 231 I 311 I 228 I 225 I 227 I 217 I 180 I 140 141 I 135 I 153 I 175 I 258 I 346 I 228 I 225 I 227 I 217 I 180 I 140 During the months of January through March and July through December, the acute low flow calculated by DFLOW exceeded the chronic low flow. In accordance with Division standard procedures, the acute low flow was thus set equal to the chronic low flow for these months. Low Flow Analvsis for Discharge to the Tributary Wetlands Currently, it is the Division's standard approach to assume that there is no available dilution in a wetlands area until such time as a mixing zone study has been completed that demonstrates the available dilution. Thus, for purposes of this analysis, low flows are summarized in Table A-5. IE3 Acute 30E3 Chronic 0 0 PELs Appendix A 0 0 0 0 0 0 0 0 Table A-5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Page 6of21 Last Revised by EO July 8, 2007 • • • Roming Fork WSD WWTF Preliminary Effluent Limits PEL-200229 IV. Technical Analysis In-stream background data and low flows evaluated in Sections II and III are ultimately used to determine the assimilative capacity of the Roaring Fork River and the Tributary Wetl~nds near the Roaring Fork W &SD WWTF for pollutants of concern. For all parameters except ammonia, it is the Division's approach to conduct a teclmical analysis of stream assimilation capacity using the lowest of the monthly low flows (referred to as the an11ual low flow) as calculated in the low flow analysis. For anunonia, it is the standard procedure of the Division to dt:\ermine assimilative capacities for each month using the monthly low Dows calculated in the low fl'ow analysis, as the regulations allow the use of seasonal flows when establishing assimilative capacities. The Division's standard analysis consists of steady-state, mass-balance calculations for most pollutants and modeling for pollutants such as ammonia. The mass-balance equation is used by the Division to calculate the maximum allowable concentration of pollutants in the effluent, and accounts for the upstream concentration of a pollutant at the existing quality, critical low flow (minimal dilu6on), effluent flow and the water quality standard. The mass-balance equation is expressed as: Where, M2 = M 3Q 3 -M1Q1 Q1 Q1 Q1 QJ M1 M2 M 3 =Upstream low flow (1E3 or 30E3) = Average daily effluent flow (design capacity) =Downstream flow (Q1 + Q2) =In-stream background pollutant concentrations at the existing quality = Calculated maximum allowable effluent pollutant concentration =Maximum allowable in-stream pollutant concentration (water quality standards) \\'hen Q1 equals zero, as is the case when the wetlands is used as the receiving waters, Q2 equals Q3 , and the following results: M2=M3 Because the low flow (Q1) for the Tributary Wetlands is considered to be zero, the assimilative capacity of the wetlands for the pollutants of concern is equal to the in-stream water quality standards. For discharge to the Roaring Fork River, the upstream background pollutant concentrations used in the mass-balance equation will vary based on the regulatory definition of existing ambient water quality. For most pollutants, existing quality is determined to be the 85 1 h percentile. For pathogens such as fecal colifom1 and E. coli, existing quality is determined to be the geometric mean . PELs Appendix A Page 7 of21 Last Revised by EO July 8, 2007 • • • Ro aring Fork \VSD WWTF Prelimin ary Effluent Limits PEL-200229 For non-conservative param eters and ammonia, the mass-ba lance equation is not as applicable and thus other approaches are consid ered wh ere appropriate . A more detail ed di scussion of the technical analysis for these parameters is provided in the pages that follow . PoJJutants Evaluated The following parameters were identifi ed by the Division as pollutants to be evaluated for this facility: • BOD5 • TSS • Percent removal • Oil and Grease • pH • Fecal Coliform • E .coli • Total Residual Chlorine • Ammonia . There are no in-stream water quality standards for BOD5, TSS, percent removal, and oil and grease for the Roaring Fork River or the Tributary Wetlands. Thus, assimilative capacities were not determined for these parameters in this section and an antidegradation review for these parameters was not conducted in Section V. The evaluation of applicable limitations for these pollutants can be found in Section VI, Regulatory Analysis . According to the Rationale for Classifi cations, Standards and Des ignations of the Upper Colorado River, there are no existing public water supply uses downstream from the Roaring Fork W &SD WWTF. For this reason, the nitrate standard, which is applied at the point of intake to a water supply, is not evaluated as part of this analysis. During assessment of the facility, nearby facilities, and receiving stream water quality, no additional parameters were identified as pollutants of concern. Roaring Fork W &SD WWTF: The Roaring Fork W &SD WWTF is located in the NE Y'.i of the NE v.i of S 13, T7S, R89W, 6th P.M.; on County Road 109, north of Carbondale, Colorado; at 39° 27' 05" latitude No1ih and 107 ° 16' 07" West longitude in Garfield County. The proposed design capacity of the facility is 0.321 MGD (0.5 cfs). Wastewater treatment is proposed to be accomplished using a mechanical wastewater treatment process. The technical analyses that follow include assessments of the assimilative capacity based on this design capacity. Nearbv Sources An assessment of nearby facilities based on EPA' s Permit Compliance System (PCS) database was conducted. According to PCS, the nearest upstre am and downstream dischargers were: • The Tov.11 of Carbondale WWTF (COG-584050), which discharges to the Roaring Fork River, approximately five miles upstream of the Roaring Fork W &SD WWTF. Due to the extremely high dilution ratio afforded by the Ro a ring Fork River, it was unnecessary to model this facility with the Roaring Fork W &SD WWTF . PELs Appendix A Page 8of21 Last Revised by EO July 8, 2007 • • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 • The Mobile Home Management Corporatio,n ( dba the H Lazy F Mobile Home Park) (COG- 588035), which discharges to the Roaring Fork River approximately two and a half miles downstream from the Roaring Fork W &SD WWTF. Two other facilities discharge to the Roaring Fork River downstream from the Roaring Fork W&SD WWTF and they are the El Rocko Mobile Home Park (COG588029), which discharges approximately five miles dovmstrear11 from the facility of concern, and the City of Glenwood Springs WWTF (C0- 0020516), which discharges approximately nine miles downstream from the facility of concern. Due to the extremely high dilution ratio afforded by the Roaring Fork River, it was not necessary to model these facilities with the Roaring'"Fork W&SD WWTF. For discharge to the Roaring Fork River, the ambient water quality background concentrations used in the mass-balance equation account for pollutants of concern contributed by upstream sources; thus, it was not necessary to model upstream dischargers together with the Roaring Fork W &SD WWTF when determining the available assimilative capacities in the Roaring Fork River. Due to the distance traveled, the significant dilution of the receiving stream and the changes in the characteristics of the receiving stream, modeling downstteam facilities in conjunction with the Roaring Fork W&SD WWTF was not necessary. For discharge to the Tributary Wetlands, due to the in-stream low flow of zero, the assimilative capacities during times oflow flow are not affected by nearby contributions. Therefore, modeling nearby facilities in conjtmction with the Roaring Fork W &SD WWTF was not necessary . Based on available infom1ation, there is no indication that other sources were a significant source of pollutants of concern. Thus, other sources were not considered in this assessment. pH: For discharge to the Roaring Fork River, an evaluation of pH data available for the Roaring Fork River near the Roaring Fork W &SD WWTF found that the 15th percentile value was well above the minimum in-stream water quality standard and the 85th percentile value was well below the maximum in-stream water quality standard. Because only limited data are available and because an1bient water quality data indicate that no further controls are needed to meet in-stream pH standards, a complex evaluation of the assimilative capacity for pH is not warranted for this facility, and the in-stream water quality standards of 6.5-9.0 su are applied. For discharge to the T1ibutary Wetlands, the full assimilative capacity of the wetlands for pH was determined to equal the in-stream water quality standards of 6.5-9.0 su. CbJorine: The mass-balance equation was used to detennine the assimilative capacity for chlorine. There are no point sources discharging total residual chlorine within one mile of the Roaiing Fork W &SD WWTF. Because chlorine is rapidly oxidized, in-stream levels of residual chlorine are detected only for a short distance below a source. Ambient chl01ine was therefore assumed to be zero. Using the mass-balance equation provided in the beginning of Section IV, the acute and chronic low flows set out in Section Ill, the chlorine background concentration of zero as discussed above, and PELs Appendix A Page 9 of21 Last Revised by EO July 8, 2007 ' • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 the in-stream standards for chlorine shown in Section II, assimilative capacities for chlorine were calculated. The data used and the res ulting calculations of the allowable discharge concentrations, M 2, are set fo1ih below. Discharne to the Roaring Fork River l !;r/i~~~1/i~~tf(JWiff{it%!$t~t?:~~'.,l z0:iJYL(cis)*>'l ·:i·Q /'.icfiJJt,crl ·.>_f!);;fmJ '.iitd l :'?~tt ·('fiig/1Jux l :t.~~}'(Ji/iaB··•1 YAJ i(i,1f:{li)· Acute Chlorine I 135 I 0.50 I 135.5 I o I 0.019 I 5.1 Chronic Chlorine 135 0.50 135 .5 0 0.011 3.0 Discharge to the Tributary Wetlands The full assimilative capacity of the Tributary Wetlands fortotal residual chlorine was determined to equal the in-stream water quality standards of 19 µg/l (acute) and 11 µg/l (chronic). Fecal Coliform and E. coli: Available studies indicate that E. coli, which is a subset of fecal coliform, is a better predictor of potential human health impacts from waterborne pathogens. Cunently, the Water Quality Control Commission has adopted standards for both pathogens and intends that dischargers will have the option of either parameter being used in establishing their effluent limits. There are no point sources discharging these pathogens within one mile of the Roaring Fork W &SD WWTF. Thus, assimilative capacities were evaluated separately. Discharge to the Roaring Fork River In the absence of E. coli ambient water quality data, fecal coliform ambient data are used as a conservative estimate of E. coli existing quality. Using the mass-balance equation provided in the beginning of Section IV, the chronic low flow set out in Section Ill, the background concentrations contained in Section II and discussed above, and the chronic in-stream standards for fecal coliform and E. coli shown in Section 11, the assimilative capacities for fecal coliform and E. coli were calculated. The data used and the resulting calculations of the allowable discharge concentrations, M 2 , are set forth below. Discharge to the Tributary Wetlands The full assimilative c apacity of the Tributary Wetlands for fecal coliform was determined to equal the in-stream water quality standard of200 colonies/100 ml (chron ic). The full assimilative capacity of the Tributary Wetlands for E coli \Vas detem1ined to equal the in-stream water quality standard of 126 colonies/100 ml (chronic). Ammonia: The Ammonia Toxicity (AMMTOX) Model is a software program designed to project the dovmstream effects of ammonia and the ammonia assimilative capacities available to each PELs Appendix A Page 10 of21 Last Revised by EO July 8, 2007 • • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 discharger based on upstream water quality and ,effluent discharges. To develop data for the AMMTOX model, an in-stream water quality study should be conducted of the upstream receiving water conditions, particularly the pH and conesponding temperature, over a period of at least one year. There were no data available for the Roaring Fork River near the Roaring Fork W &SD WWTF that could be used as adequate input data for the AMMTOX model. Therefore, the Division standard procedure is to rely on statistically-based, regionalized data for l?ff and temperature compiled from simi lar facilities and receiving waters. Upstream ammonia data for each month were not available for discharges to the Roaring Fork River. Thus, the mean total ammonia concentration found in the Roaring Fork River as summarized in Table A-3 was used as an applicable upstream ammonia concentration reflective of each mo11th. The AMMTOX may be calibrated for a munber of variables in addition to the data discussed above. The values used for the other variables in the model are listed below: • Stream velocity= 0.3Q0.4d • Default ammonia loss rate= 6/day • pH amplitude was assumed to be medium • Default times for pH maximum, temperature maximum, and time of day of occurrence • pH rebound was set at the default value of 0.2 su per mile • Temperature rebound was set at the default value of 0.7 degrees C per mile . The results of the ammonia analyses for the Roaring Fork W &SD WWTF at both potential receiving waters are presented in Tables A-6 and A-7. Table A-6 AMMTOX Model Results for Discharge to the Roaring Fork River at the Roaring Fork W&SD WWTF Month Total Ammonia, chronic (mg/I) Total Ammonia, acute (mg/I) January >45* >45* February >45* >45* March >45* >45* April >45* >45* May >45* >45* June >45* >45* July >45* >45* August >45* >45* September >45* >45* October >45* >45* November >45* >45* December >45* >45* * -Treated municipal sanitary sewage effi uent is expected to have a total ammonia concentration Jess than 45 mgll. PELs Appendix A Page 11 of 21 Last Revised by EO July 8, 2007 ' • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 Table A-7 AMMTOX Model Results for Discharge to the Tributary Wetlands at the Roarin2 Fork W &SD WWTF Month Total Ammonia, chronic (me./}) Total Ammonia, acute (m~/l) January 5.6 19 February 5.6 19 March 5.4 18 April 5.4 18 May ' 5.5 18 I June 5.1 19 July 4.4 19 August 4.7 22 September 4.6 20 October 5.0 19 November 5.5 18 December 5.4 18 V. Antidegradation Review As set out in The Basic Standards and Methodologies of Swface Water, Section 31.8(2)(b ), an antidegradation analysis is required except in cases where the receiving water is designated as "Use Protected." Note that "Use Protected" waters are waters "that the Commission has determined do not warrant the special protection provided by the outstanding waters designation or the antidegradation review process" as set out in Section 31.8(2)(b ). The antidegradation section of the regulation became effective in December 2000, and therefore antidegradation considerations are applicable to this PELs analysis. According to the Classifications and Numeric Standards for Upper Colorado River Basin and North Platte River (Planning Region 12), stream segment COUCRF03a is Undesignated. Thus, an antidegradation review may be conducted for this segment if new or increased impacts are found to occur. For discharge to the Roaring Fork River, the ratio of the flow of the Roaring Fork River to the Roaring Fork W &SD WWTF design flow is 270: 1 a t low flows. Section 31.8 (3)( c) specifies that the discharge of pollutants should not be considered to result in significant degradation of the reviewable waters if the flow rate is greater than 100: 1 dilution at low flow. Thus, Section 31.8(3)(c) PELs Appendix A Page 12 of21 Last Revised by EO July 8, 2007 ' • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 of the regulations is met and no fuither antidegrad~tion evaluation is Decessary for discharge to the Roaring Fork River. For discharge to the Tributary Wetlands, however, the antidegradation review must proceed. The Division's Anti degradation Significance D etermination for New or Increased Water Quality Impacts Procedural Guidance provides guidance on the det erm ination of new or increased water quality impacts and significant degradation. Consistent with cunent Division procedures, the baseline water quality (BWQ) concentrations for pollutants of concern should be established so that it can be used as part of an ti degrad ation reviews. BWQ is defined by the Division as the condition of the water quality as of September 30, 2000. Furtheffl1ore, the Division specifies that BWQ concentration will include the influence of the discharger if it was in place on September 30, 2000. Accordingly, BWQ concentrations are detennined based on either downstream ambient water quality data, or based on the following equation: Where, M Q B WiQ -eff ef! + M Q -u~ uls Q eff + Quls BWQ = Qu1s Muls Qefl = Meff = Baseline water quality Upstream low flow during the antidegradation period Upstream background pollutant concentration at the existing quality during the antidegradation period 2-year average flow 2-year average effluent pollutant concentration When Q1115 equals zero, as it is considered to be when the facility discharges to the wetlands, the following results: BWQ =Meg · To establish M effi monthly average effluent concentrations available from PCS for flow, fecal coliform, E. coli, total residual chlorine, and ammonia were used. PCS data for flow, fecal coliform and total residual chlo1ine were obtained for a period of record from October 1998 through September 2000 and averaged for flow and total residual chlorine, and the geometric mean was determined for fecal coliform and E. coli. For ammonia, there were insufficient data available based on a period of record from October 1998 through September 2000, and thus data for a period of record from April 1998 through September 2000, \vhich were the only available data during the antidegradation period, were obtained. The average concentrations for each month were then determined and were used as the Mefffor the respective month. For E. coli, no effluent data were available and therefore an effluent concentration equal to 0.32 times the fecal coliform effluent concentration was used consistent with the Division's E. coli policy. PELs Appendix A Page 13of21 Last Revised by EO July 8, 2007 • • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 Pursuant to the approach discuss ed above, the equation for BWQ, and the available data, the BWQ conc e ntrations for the remainin g pote ntial pollutants of concern, except ammonia, are set forth in Table A-8 . Table A-8 BWQ Concentrations for Potential Pollutants of Concern Except Ammonia For Discharge to the Tributa Wetlands ']/Q !fJl"(I:Jfjj;:~. t{·"iJ:tJ,lliJ;j~}!· Fec a l Colifonn (#/J OO ml) 18 0.019 1.0 0 18 200 E.coli (#/100 ml) 5.8 0 .019 1.0 0 5.8 126 TRC(mg/l) 0.015 0.019 0 0 0.015 0.011 For ammonia, BWQ concentrations are calculated by incorporating the average effluent concentrations and average flow, and the ambient water quality and low flows for the antidegradation period into the AMMTOX and determining the maximum ammonia concentration downstream . In cases where the BWQ concentration exceeds the water quality standard, the calculated BWQ concentration must then be set equal to the water quality standard. This occurred for total residual chlorine. Determinations of Antidegradation Based Average Concentrations New or increased impacts on the Tributary Wetlands are expected as a result of this permit issuance because the concentration or loading based on proposed water quality-based effluent limits (WQBELs) is greater than the existing p ermit limit or load for the following pollutants: • Total ammonia for all months. Note that the evaluation of the ex isting pem1it limit and load and the water quality-based effluent limit and load is fmiher discussed at the end of this assessment. For fecal coliform, E. coli and total residual ch101ine, new or increased impacts are not expected to result from this p e nnit issuance because the proposed water quality-based effluent limits and loads are more stringent than ex isting limits and loads, and therefore the anti degradation review process is concluded for these pollutants . PELs Appendix A Page 14of21 Last Revised by EO July 8, 2007 • • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 For the bulleted pollutants, the antidegradation review procedure must continue to determine if impacts are significant. Impacts are deemed to be significant if the calculated assimilative capacity exceeds the calculated antidegradation-based average concentration (ADBAC). ADBACs are calculated using the significant concentration threshold (SCT), which is the additional amount of pollutant above BWQ concentration that would not cause significant degradation. Section 31.8 (3)(c) specifies that the discharge of pollutants should not be considered to result in significant degradation of the revie\vable waters if one of the following summarized conditions is met: • For bioaccumulative toxic pollutants such as mercury, the new or increased loading frorh the source under review is Jess than 10 percent of the exi~ting total load to that portion of the segment impacted • For all other pollutants o the flow rate is greater than 100: 1 dilution at low flow; or o the new effluent load is less than 15 percent of the remaining assimilative capacity; or o only a temporary change in water quality will result. The SCT for most pollutants equals the BWQ concentration plus 15 percent of the remaining assimilative capacity, and is calculated by the following equation: Where, SCT= 0.15 x (WQS-BWQ) + BWQ WQS = water quality standard (chronic standard or, in the absence of a chronic standard, the acute standard) ADBACs are then determined by re-calculating the mass-balance equation using the SCT in place of the water quality standard, as in the following equation: Where, Qi Q2 QJ M1 SCT ADBAC= SCTxQ3 -M1 xQ Q2 =Upstream low flow (1£3 or 30E3) =Average daily effluent flow (design capacity) =Downstream flow (Q1 + Q2) = Ambient existing water quality concentration (From Section II) = Significant concentration threshold \Vhen Q1 is equal to zero, Q2 equals Q3, and therefore the following equation results: ADBAC=SCT PELs Appendix A Page 15of21 Last Revised by EO July 8, 2007 ' • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 ADBACs for total ammonia are detem1ined by substituting the SCT in place of the chronic standard in the AMMTOX model. The resulting AD BA Cs for total ammonia are set forth in Table A-9. Note that AD BA Cs for ammonia are evaluated based on the AMMTOX model , which generates monthly ADBACs. Table A-9 ADBACs for Total Ammonia For Discbarpe to the Tributary Wetlands Month Total Ammonia, chronic (mg/I) I January 3.8 February 2.9 March ' 3.1 April 3.7 May 2.8 June 1.8 July 3.4 August 2.5 September 1 3.2 October 3.2 November 2.3 December 2.8 In lieu of being subject to the ADBACs, facilities have the option of selecting non-impact limits (N1Ls), which are concentration limits based on their existing permitted load and the proposed design flow. By agreeing to meet the NILs, new or increased impacts will not occur and thus ADBACs will not be required to be considered in CDPS permits. For those pollutants for which permit limits have not yet been established, an implicit load allocation is determined and an implicit permit limit is established. In accordance with the Division's E.coli policy, an implicit limit for E. coli is detennined as 0.32 times the pennit limit for fecal coliform. For all pollutants evaluated, a summary of the existing pennit limits (including implicit limits), the existing permitted load, the new WQBELs , the new WQBEL load, ADBACs, and NILs are contained in Table A-10 . PELs Appendix A Page 16of21 Last Revised by EO July 8, 2007 • • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 Table A-10 WQBELs, ADBACs, and Non-Impact Limits Summary For Discharge to Tributary Wetlands Parameter WQBEL ADBAC Current NIL Limit Fecal colifonn (#/100 ml) 200 45 6,000 2,040 1 E.coli (#1100 ml) 126 24 2,000 680 1 TRC (mg/}) 0.011 0.011 0.038 0.0131 Jan. Total Amm. (mg/l) 5.6 3.8 10 3.4 Feb. Total Amm. (mg/I) 5.6 2.9 10 3.4 Mar. Total A.mm. (mg/l) 5.4 3.1 10 3.4 Apr. Total A.mm. (mg/I) 5.4 3.7 6.0 2.0 May Total Amm. (mg/l) 5.5 2.8 6.0 2.0 Jun. Total Amrn. (mg/]) 5.1 1.8 6.0 2.0 Jul. Total A.mm. (mg/I) 4.4 3.4 6.0 2.0 Aug. Total Amm. (mg/l) 4 .7 2.5 6.0 2.0 Sep. Total Amm. (mg/I) 4.6 3.2 6.0 2.0 Oct. Total Amm. (mg/I) 5.0 3.2 10 3.4 Nov. Total A.mm. (mg/I) 5.5 2.3 10 3.4 Dec. Total Amm. (mg/I) 5.4 2.8 10 3.4 1 -NIL greater than WQBEL so the WQBEL must apply. The existing permitted load, the new WQBELs load, and the NIL were calculated using the following equations: Where, Existing permitted load= Mpermitted x Qpermitted x 8.34 New Tf!QBELs load= M 2 x Q2 x 8.34 NIL =Existing permitted load+ Q2 + 8.34 Mpermitted Qpermitted M2 Q1 = Existing permit limit or implicit permit limit as of September 2000 (mg/I) =Design flow used in the existing pem1it as of September 2000 (mgd) =Maximum allowable discharge concentration (mg/I) =Average daily effluent flow (design capacity in mgd) In the interests of limiting tables to only those explicitly necessary, detailed calculations of the existing pem1itted load, proposed WQBELs load and NIL are not provided. However, the values for each factor in the equations noted above can be easily found in this assessment and therefore calculations can be easily verified . PELs Appendix A Page 17 of21 Last Revised by EO July 8, 2007 • • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 VI. Regulatory Analysis Regulation No. 62, the Regulations for Effluent Limitations, includes effluent limitations that apply to all discharges of wastewater to State waters, with the exception of storm water and agricultural return flows. These regulations are applicable to the discharge from the proposed Roaring Fork W&SD WWTF. Table ~-11 contains a summary of these limitations. Table A-11 BOD5 TSS, mechanical plant TSS, aerated lagoon 110 mg /I 75 mg/I NA TSS, non-aerated lagoon 160 mg/I 105 mg/I NA BOD5 Percent Removal NA 85% NA TSS Percent Removal NA 85% NA Total Residual Chlorine NA NA H NA NA Oil and Grease I NA NA Note that the TSS limitations shown above vary based on the type of wastewater treatment processes used at the facility. The Regulations for Effluent Limitations waive the 85 percent removal requirements for TSS where waste stabilization ponds, both aerated and non-aerated, are used as the principal process for treating domestic wastes. Section 62.4(1) of the Regulations for Effluent Limitations also indicates that numeric limitations for fecal coliform shall be determined. The State has developed the Procedure for Selection of Fecal Coliform Limitations Permit Conditions that specifies a 30-day geometric mean limit of 6,000 colonies per 100 ml and a 7-day geometric mean limit of 12,000 colonies per 100 ml when the ratio of the receiving stream flow to design flow is greater than ten to one. The Procedure for Selection of Fecal Coliform Limitations Permit Conditions also specifies that the 7-day geometric mean limit must be calculated as two times the 30-day geometric mean limit. Comparably, for E. coli, the Division establishes the 7-day geometric mean limit as two times the 30-day geometric mean limit and also includes maximum limits of 2,000 colonies per 100 ml (30-day geometric mean) and 4,000 colonies per 100 ml (7-day geometric mean) . PELs Appendix A Page 18 of21 Last Revised by EO July 8, 2007 ' • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 VII. Preliminary Effluent Limits The potential PELs reflected in Tables A-12 and A-13 include the consideration of the following: • Assimilative capacities as discussed in the technical analysis contained in Section JV • ADBACs as discussed in the antidegradation review provided in Section V (applicable to discharge to the Tributaiy Wetlands, only) • NILs, as discussed in Section V (applicable to discharge to the Tributary Wetlands, only) • Effluent limits prescribed by the regulations based on t}fe regulatory analysis provided 'in Section VI. · Table A-12 Proposed Roaring Fork W &SD WWTF Expansion Preliminary Effluent Limits for Discharge tO the Roaring Fork River BOD5 (mg/I) I 45 (7-day average), 30 (30-day average) BOD5 (% removal) TSS, mechanical plant (mg /1) TSS, mechanical plant(% removal) Oil and Grease (mg /I) H (s.u.) Fecal Coliform(#/100 ml) E.coli (#/JOO ml) Total Ammonia, (mg /l) PELs Appendix A 85 (30-day average) 45 (7-da e) lO(maximum 6 .5-9.0 (minimum-maximum) ·~itf~i~W~i~ffc§~~~-t! 12000 (7-day geomean), 6000 (30-day geomean) 4000 (7-day geomean), 2000 (30-day geomean) 0.5 (daily maximum), Reoort (30-day average) '.ii,L\;)~1~$1/J;~~~~m~~!i\,f Report (daily maximum), Report (30-day average) Page 19 of21 NA NA NA NA NA NA NA NA Last Revised by EO July 8, 2007 ' • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 TabJe A -13 Proposed Roaring Fork W &SD WWTF Expansion Preliminary Effluent Limits for Discharne to the Tributarv Wetlands BOD s (mg /!) BODs (%removal) TSS , mechanical plant (mg/I) Fecal Colifonn (#/JOO ml) E.coli (#1100 ml) Total Residual Chlorine (mg /I) Total Ammonia, January (mg/I) Total Arrnnonia, February (mg/1) Total Ammonia, March (mg/I) Total Ammonia, April (mg/I) Total Ammonia, May (mg/J) Total Ammonia, June (mg /I) Total Ammonia, July (mg /l) Total Anm10nia, August (mg/I) Total Ammonia, September (mg /I) Total Anm10nia, October (mg /I) Total Ammonia , November (mg /I) Total Arrnnonia, December (mg/J) PELs Appendix A 45 (7-day average), 30 (30-day average) 85 (30-day average) 45 (7-day averag e), 30 (30-day average) 85 (30-day average) JO (maximum) Reoort (minimum) 65-9.0 (minimum-maximum) ,~~i~#f~~fflfl~~!c- 400 (7-day geomcan), 200 (30-day geomean) 252 (7-day geomean), 126 (30-day geomean) 0.019 (daily maximum), 0.011 (30-day average) .. {~,~fl~;~~~~~~fi·-'! 19 (daily maximum), 5.6 (30-day avcrnge) 19 (daily maximum), 5.6 (30-day average) 18 (daily maximum), 5.4 30-dav average) 18 (daily maximum), 5.4 (30-day average) 18 (daily maximum), 5.5 (30-day average) 19 (daily maximum), 5.1 (30-dav average 19 (daily maximum), 4 .4 (30-dav average 22 (daily maximum), 4.7 (30-day average) 20 (daily maximum), 4 .6 (30-day average) 19 (daily maximum), 5 (30-dav average 18 (daily maximum), 5 .5 (30-day average) 18 (daily maximum), 5.4 (30-day average) Page 20 of21 NA NA NA NA NA NA 3 .3 (2-yr average) 3.4 (30-day geomcan) 3.3 (2-yr average) 3.4 (30-day geomean) 3.3 (2-yr average) 3.4 (30-day geomean) 3 .3 (2-yr average) 2 (30-day geomean) 2.5 (2-yr average) 2 (30-day geomean) 2.5 (2-yr average) 2 (30-day geomcan) 3 (2-yr average) 2 (30-day geomcan) 3 (2-yr average) 2 (30-day geomean) 3 (2-yr average) 2 (30-day geomean) 2.5 (2-yr average) 3.4 (30-day geomean) 2.5 (2-yr average) 3.4 (30-day geomean) 3.3 (2-yr average) 3.4 (30-day geomean) Last Revised by EO July 8, 2007 • • • Roaring Fork WSD WWTF Preliminary Effluent Limits PEL-200229 For discharges to the Roaring Fork River, the more stringent total residual chlorine, fecal coliform and E. coli limits, as set forth in the Regulatory Analysis Section VI, are included as PELs as they are more stringent than the effluent limits for these parameters presc1ibed in the Section IV Technical Analysis. Also, limitations for ammonia were not necessary for discharge to the Roaring Fork River because the assimilative capacity of the receiving water, as discussed in Section IV, is large enough to establish total ammonia effluent concentrations for all months at 30 mg/l. Because treated sanitary sewage effiuent is not expected to have a total ammonia concentration greater than 30 mg/l, no additional allocations were determined as per Division procedure and monitoring, only, is specified. ,•' For discharges to the Tributary Wetlands, the more stringent total residual chlorine, fecal coliform and E. coli water quality-based effluent limits, as set forth in the Teclmical Analysis Section IV, are inclu.ded as PELs as they are more stringent than the effluent limits for these parameters prescribed in the Regulatory Analysis Section VI. Furthermore, as explained in the Regulatory Analysis Section VI, the fecal coliform and E. coli 7-day geometric mean limits are two times the 30-day geometric mean limits, respectively, as per Division procedures. A detem1ination of which PELs ultimately apply will be dependent on decisions made by the Roaring Fork W&SD WWTF. VIII . References Classifications and Numeric Standards for Upper Colorado River Basin and North Platte River (Planning Region 12), Regulation No. 33, CDPHE, WQCC, effective September 1, 2007. The Basic Standards and Methodologies for Surface Water, Regulation 31, CDPHE, WQCC, Effective December 31, 2005. Antidegradation Significance Determination for New or Increased Water Quality Impacts, Procedural Guidance, CDPHE, WQCD, December 2001. Memorandum Re: First Update to Guidance Version 1.0, CDPHE, WQCD, April 23, 2002 . Upper Colorado River Basin Regulation No. 33 Triennial Rulemaking Rational, CDPHE, WQCD, effective May 6, 2003. Policy Concerning Escherichia coli versus Fecal Coliform, CDPHE, WQCD, July 20, 2005. Procedure for Selection of Fecal Coliform Limitations Permit Conditions, CDPHE, WQCD, April 7, 1976. Regulations for Effluent Limitations, Regulation 62, CDPHE, WQCC, December 30, 1998 . PELs Appendix A Page 21 of21 Last Revised by EO July 8, 2007 • • • 22.5(2)(c) Analysis of existing treatment works The existing waste water treatment facility was constructed in 1996 for the golf course development of Aspen Glen. At the time, Garfield County required that the facility be planned as a regional facility and create a water and sanitation district. The Roaring Fork Water and Sanitation District was created and the WWTF was master planned to be a regional facility . During the original planning of the WWTF, odors were a concern because of the close proximity of possible development , as a result, all of the processes are covered and odor control was installed. The odor control system that was installed has not been operated a great deal because odor has not been a problem. The facility was originally master planned to be built in three phases of 0.107 MGD for an ultimate buildout of 0.321 MGD . The facility was designed such that it could easily be expanded by just adding aeration basins and clarifiers. The WWTF is an activated sludge facility with secondary clarification , tertiary filtration, chlorine disinfection, aerobic digestion of the bio-solids, and the effluent discharges to wetlands that are adjacent to the Roaring Fork River. In 1996, the first phase of 0.107 MGD was completed and now is currently using roughly 55% of the capacity and is meeting the discharge limits. The District does not have an inflow or an infiltration problem so no un-accounted flows were projected. The peak month 30-day average flows for 2007 so far was 59 ,000 gallons per day in the month of August, which is approximately 55% of the facility's permitted capacity. The peak month 30-day average organic loading or BOD for 2007 so far was 66.8 pounds per day which is approximately 30% of the facility's permitted capacity of 225 lbs /day . A copy of the WWTF's annual report for 2007 is attached as figure 3. The hydraulic and organic loadings would suggest that the facility is under loaded and there is not a need for an expansion but as described in more detail in the service area section of this report, the District is anticipating an accelerated growth rate over the next several years. The District believes in order to continue to operate within the discharge permit; the facility must be constructed and online as soon as possible . As mentioned previously, the WWTF discharges directly to wetlands that are adjacent to the Roaring Fork River. Because of the discharge location, the current discharge limits are very stringent but the WWTF has had no problem in meeting the limits . The facility has had no issues with permit compliance and has operated well within the limits. The new PELs that were received will be very hard to meet during certain months of the year when this facility is receiving increased flows . As a result, the Board of Directors has decided to look at the option of discharging to both the wetlands and the river. The District is considering a pipeline to the river with an outlet into th e wetlands . The pipeline would be operated in such a fashion that during the months when the District is confident it can meet the discharge limits it would discharge to the wetlands an d the remainder of the time it would be directly di sc harg ed to th e river. This option will be exp lored further when the des ign of this phase starts . 1:\1996 \96059\A -82 WWTF Expansion Plannin g\2 -WWTF Ex pansion Permittin g\R eg 22 Final.doc Page 6of12 , ANNUAL REPORT Plant: --'-'{_----'--r~~-'--s_})....._ __ Year : ,;z Uo 7. 1Month BOD TSS FLOW PH MAX AVG LBS IN OUT IN OUT AVG MAX MIN MAX CL2 TD Se TDSw FECAL NH4 AVG MAX Jan IS1 3 120 2-. 0 -j) D~9 7 3 7 . i .Q) 1~5 5 '159 2 (J . n l ~d Lil. s-l s--. } Feb ix Lt 2 ll~ y . 0 ~/. -OL-\CJ I .~ 7 , ;-.o I '-\ )._ \ ~ '1 l Ji 0 . '-114 5'-S-.~ 7 (,' Mar 1 r o r [1 l t-f .D"3l . ()-'-j t.) 7. 5 7,,t--\ nl -4 t'f 3~0 1 n .05~-5 ~-33 .l .10 Apr JY1 I JoJ 2. .0) 7 ,oS-'1 17,. ~q 7,11 ,vi lf) l '1Dh 0 I I )J:J ~1 /, ( {;o.> May ).;)..1 3 II. D :2_ .OSl ,o5{ /. l 2 s-. {)I I &s 213 AV ~O\L\J l L.8 i 0 5. 5- Jun .[ J-5 L) 9~ I .05l . Ol D 1.5 f. L.j . ol 188 I cu )o . 009 i. s 8 8 ·73_.) Jul lb :i_ .., \~8 )_ . 05:2.. . 012-1.3 7 . 4 • DI \ 'f ' 1q1 t{ .l3i '-14-.9 /..I. s- Aug I\ i I l D-'-\ :;_ • O")'f /) l l /.2 (. '1 . or d.. o7 fJ.. 01 2o . ()!). () 55.2 LL .3 Sep Oct Nov Dec TOTAL AVG YEAR MAX • • • 22.5(2)(d) Consolidation analysis The Roaring Fork Water and Sanitation District WWTF is the regional WWTF so consolidation was not considered. Several other smal l package plants in the region have considered consolidation but they have determined it is not economically feasible because of the high cost of the infrastructure required to get to the WWTF. The existing WWTFs near the District are across the Roaring Fork River and would require a river crossing as well as a regional lift station. As infrastructure to the edge of the service area of the District expands, many of these WWTFs will consolidate with the District. The District has planned for all of the existing developments to someday connect to the District when it is feasible. The proposed site plan is attached as figure 4 . I:\ 19 96 \960 59 \A-82 WWTF Expa ns ion Pl a nnin g\2 - WWTF Ex pans ion Permittin g\Reg 22 Fin a l.d oc Page 7of12 ' • • ·' \ ~ • ~ ' ! ~ ~ •· ~ ~ i I l i i \ ' ' ' \ \ ' ' \ . ' , ' , \'. I ··,·.··I\ __ ' . " ......... \>'.· .... · ., ' ' ':", ·, .... ·: • ' \ " \ ·\'. -C' \ · ... ·. \', . \' ·.·· ·.\".·\. '"\·::. \'.> \ .i ..... \ \\\ .. . \ \ \ \ \ ·. u \ lO. ·.OJ o · ·~ Job Ne. Orolf'n by: NOT )Jcint La outs .. / / I / / 96059A -82 CLL 2 PRELIMINARY 6 FOR . y ~I• 7/25/2007 1 CONSTRUCTION sc~~~~;;~.I. ~o:~~~.!o~~R Option 2 j \P£ om••z , 2 Figure 4 • • • 22 .5(2)(e) Financial capability The existing financial system in place consists of quarterly service fees , a mill levy and tap fees for new customers. The District has been very pro-active since the inception in 1996 about updating service and tap fees. The two major developments within the District were required to pre-pay tap fees for the future WWTF expansion; the expansion that is being p lanned for in this application. With that being said, the District is in a very good financial situation with approximately enough money in the bank to pay for this expansion. The initial construction estimate for this expansion is roughly $2 million. An engineer's cost opinion of the facility is attached as figure 5. A financial statement and independent auditor's report from December 31, 2006 verifying the Districts account balance is attached as figure 6 . In the case that the contractors' bids come in higher than expected, the D i strict then would take out a loan through a private bank and would be able to repay it in 1 -3 years from tap fees. The operating costs of the WWTF are not expected to dramatically increase until the flows increase substantially. The District examines the service fees every 2 -3 years to make sure that the operational costs are being covered and depreciation is also being covered for replacement of major infrastructure when it wears out. The District is not planning on adjusting the service fees until the next time they are examined in approximately 2 -3 years . 1:\1996 \96059\A -82 WWTF Ex pan sion Pl annin g\2 - WWTF Ex pansion Permittin g\Reg 22 Fin al.doc Page 8of12 • • • RFWSD WWTF Master Plan and Permitting WWTF 0.214 MGD Expansion Cost Opinion -, Pretreatment Building Automatic Bar Sc ree n (0 .321 MGD) 1 125 ,000 $125 ,000 .00 Control Building Blowers 2 50,000 $100 ,000 .00 Slu dg e Pumps 2 20 ,000 $40,0 00 .00 Aeration Basin Con c rete Slab 126 CV 500 $63,000 .00 Con c rete Walls 139 CV 8 00 $111 ,200.00 En c losure 32 48 sf 20 $64 ,960 .00 Ae ra tion Piping 1 Is 60 ,000 $60 ,000.00 PipinQ 30 If 80 $2,400 .00 Valves 2 ea 1,000 $2 ,0 00.00 Fittings 2 ea 500 $1,000 .00 Hand Rails 1 Is 4 ,000 $4 ,000 .00 Digestor Con c rete Slab 60 CV 500 $30 ,000 .00 Co ncrete Walls 17 8 CV 800 $142,400 .00 Aeration Pip ing 1 Is 20 ,000 $20 ,000 .00 Piping 50 If 80 $4,000.00 Fittings 4 ea 500 $2,000.00 Valves 4 ea 1,000 $4 ,000 .00 Hatch 8 ea 2 ,000 $16 ,000 .00 Misc Weirs and Baffles 2 Is 2 ,000 $4 ,000.00 Clarifier Concrete Slab 56 CY 500 $28 ,000 .00 Concrete Walls 70 CV 800 $56,000 .00 Sludge Collection Equipment 2 Is 60 ,000 $120 ,000 .00 Enclosure 1230 sf 30 $36 ,900 .00 Site Work Pipe effluent to River 250 ft 100 $25 ,000 .00 Belt Press 1 LS 200 ,000 $200 ,000.00 Mo bilization 10 % $126,186.00 Contingency 20 % $252 ,372 .00 Soft Costs Legal 0 .5% $8 ,202.09 Design 7 .0% $114,829 .26 Surv eying -Engin e ering 2 .0% $32,808.36 Surveying -Construction 3.0 % $49,212 .54 Co nstruction Man agement 7.0 % $114,829 .26 TOTAL COST $1 ,960,299.51 COST PER GALLON $9.16 *b uild ings , s ite wo rk and a uxiliary equipm e nt are not included within this estimate ** This is a cost o pinion and s hould only be used for planning purp oses as the construction costs in today's co nstruction c limat e change daily Figure 5 1:119961960 59\A-8 2 WWT F Expansion Planningl Cost Estimatel WW TF Ph ase 2 Cost Esti mate .x is 10/4/2007 • • • ROARING FORK WATER AND SANITATION DISTRICT Financial Statements and Independent Auditors' Report December 31, 2006 Figure 6 • • • Ro aring Fork Water & Sa nitation District Table of Contents MANAGEMENT'S DISCUSSION AND ANALYSIS INDEPENDENT AUDITORS' REPORT FINANCIAL STATEMENTS Statement of Net Assets Statement of Revenues, Expenses and Changes in Net Assets . Statement of Cash Flows Notes to the Financial Statements SUPPLEMENTAL INFORMATION Schedule of Revenues , Expenses and Net Assets - Budget and Actual (Non-GAAP Budgetary Basis) Page 2 3 4 5 13 • • • INDEPENDENT AUDITOR'S REPORT Board of Directors Roaring Fork Water & Sanitation District Carbondale, Colorado We have audited the accompanying financial statements of Roaring Fork Water & Sanitation District as of, and for the year ended, December 31, 2006 , as listed in the table of contents. These financial statements are the responsibility of the District's management. Our responsibility is to express an opinion on these financial statements based on our audit. We conducted our audit in accordance with auditing standards generally accepted in the United States of America. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatements . An audit includes exam ining, on a test basis , evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management , as well as evaluating the overall financial statement presentations . We believe that our audit provides a reasonable basis for our opinion . In our opinion, the financial statements present fairly, in all material respects, the financial position of Roaring Fork Water & Sanitation District as of December 31, 2006 , and the changes in its financial position, and its cash flows for the year then ended, in conformity with accounting principles generally accepted in the United States of America . Management's discussion and analysis on pages i through iii, is not a required part of the basic financial statements but is supplementary information required by Governmental Accounting Standards Board. We have applied certain limited procedures, which consisted principally of inquires of management regarding the methods of measurement and presentation of the required supplementary information. However, we did not audit the information and express no opinion on it. Our audit of the 2006 financial statements was made for the purpose of forming an opinion on the basis financial statements taken as a whole . The schedules listed as supplemental information in the table of contents are presented for purposes of additional analysis and are not a required part of the basic financia l statement of Roaring Fork Water & Sanitation District. Such information has been subjected to the auditing procedures applied in the audit of the basic financial statements and, in our opinion, is fairly stated in all material respects in relation to the basic financial statements taken as a whole . "'1£lle,v, Stv~ & A~ey, P.C. Miller, Stranger & Associates, P.C . Certified Public Accountants May 18, 2006 -1- • • • Roaring Fork Water & Sanitation District Notes to the Financial Statements Note 1-Summary of Significant Accounting Policies The Accounting policies of the Roaring Fork Water & Sanitation District (the District) conform to generally accepted accounting principles as applicable to governments. The following is a summary of the more significant pol icies consistently applies in the preparation of financial statements . Principles determining Scope of Reporting Entity The District was established by statute on May 5, 1994, and is governed by a five member Board of Directors . The District has no component units nor is it financial accountable for any other entity defined by the Governmental Accounting Standards Board (GASS) Statement No. 14. Basis of Presentation -Fund Accounting The operations of the District are accounted for as an enterprise fund. Enterprise funds are used to account for operations (a) that are financed and operated in a manner similar to private business enterprises -where the intent of the governing body is that the costs (expenses, including depreciation) of providing goods or services to the general public on a continuing basis be financed or recovered primarily through user charges; or (b) where the governing body had decided that periodic determination of revenues earned, expenses incurred, and/or net income is appropriate for capital maintenance, public policy, management control, accountability or other purpose . Basis of Accounting The District's uses the accrual basis of accounting. Revenues are recognized when earned, and expenses are recognized when incurred . Operating revenues and expenses generally result from providing services in connection with the District's principal ongoing operations. All revenues and expenses not meeting this definition are reported as non- operating revenues and expenses . The Roaring Fork Water & Sanitation District has adopted the provisions of Statement No . 34 of the Governmental Accounting Standards Board Basic Financial Statements - and Management's Discussion and Analysis -for State and Local Governments. This statement established standards for external financial reporting for all state and local governmental entities which includes a statement of net assets, a statement of activities and changes in net assets, and a statement of cash flows. It requires the classification of net assets into three components : invested in capital assets, net of related debt; restricted; and unrestricted. These classifications are defined as follows : • Invested in capital assets, net of related debt -This consists of capital assets, including restricted capital assets, net of accumulated depreciation and reduced by the outstanding balances of any bonds, mortgages, notes or other borrowings that are attributable to the acquisition, construction, or improvement of those assets . -5- • • • ROARING FORK WATER & SANITATION DISTRICT Notes to the Financial Statements NOTE 1 ·SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (continued) Capital Assets • Restricted -This consists of constraints placed on net assets use through external restr ic tions imposed by creditors (such as through debt covenants,), granters, contributors, or law or regulations of other , governments or constraints • Unrestricted -This consists of net assets that do not meet the definition of "restricted" or "invested in capital assets, net of related debt". The fund of the District is accounted for on a cost of service or "capital maintenance" measurement focus . This means that all assets and all liabilities associated with the activity of the District are included on the balance sheet. Equipment and property are that cost $1,000 and has a minimum life of three years is recorded at cost. Depreciation of all fixed assets is charged · as an expense against operations . Depreciation is provided over estimated useful lives of 5-40 years using the straight-line method . Repairs and maintenance expense is charged to expense as incurred while significant betterments and replacements are recorded as increases to equipment. As assets are retired or disposed of, the cost and associated accumulated depreciation are removed from the accounts, and gains or losses on the sale or disposal are included in income. Budgetary Basis of Accounting The annual budget is prepared and approved by the Board of Directors in accordance with the State of Colorado Financial Management Manual. The budget is submitted to Garfield County and the District adopts an appropriation resolution for the next fiscal year before December 31 . The Board of Directors may amend the appropriation resolution at any time during the year if warranted by circumstances. The District appropriates, and may not exceed appropriation, at a total fund level. The budget basis of accounting differs from the generally accepted accounting principles (GAAP) basis in that contributed capital (plant investment fees) is included as revenue; outlays for debt retirement and acquisition of fixed assets are included as expenses . -6- • • • ROARING FORK WATER & SANITATION DISTRICT Notes to the Financial Statements NOTE 1 -SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (continued) Fair Value of Financial Instruments The District's financ ial in strum ents include cash and cash equivalents, accounts receivable and accounts payable . The District estimates that the fair value of all financial instruments at Decem ber 31, 2006 does not differ materia lly from the aggregate carrying values of its financial inst ruments recorded on the accqrnpanying balance sheet. The · Carrying amounts of these financial instruments appro'ximately fair value because of the short maturity of these instruments. Estimates The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect certain reported amounts and disclosures . Accordingly , actual results could differ from those estimates . Fi xed Assets The fund of the District is accounted for on a cost of service or "capital maintenance" measurement focus . This means that all assets and all liabilities associated with the activity of the District are included on the balance sheet. Equipment and property are recorded at cost. Depreciation of all fixed assets is charged as an expense against operations. Depreciation is provided over estimated useful lives of 5-40 year using the straight-line method. Repairs and maintenance expense is charged to expense as incurred while sign ificant betterments and replacements are recorded as increases to equipment. As assets are retired or disposed of, the cost and associated accumu lated depreciation are removed from the accounts, and gains or losses on the sale or disposal are included in income . Allowance for Doubtful Accounts All service fees become a lien on property if not paid . All service fees were considered collectable at December 31, 2006 . Compensated Absences At December 31 , 2006 there were no accrued compensated absences . Receivables and Payables Property ta xes are levied on December 15, of each year , and attach as an enforceable lien on property as of January 1. Ta xes are due as of January 1 of the following year and are payable in two equal installments due February 28 and June 15 if paid in installments, or April 30 if paid in full with a single payment. The ta xes are Delinquent as of August 1. If the ta xes are not paid within the subsequent statutory periods , the property will be sold at public auction . The County bill and collects the property ta xes and remits collections to the District on a monthly basis . No provision has been made for uncollected taxes, as all taxes are deemed collectible . -7- • • • ROARING FORK WATER & SANITATION DISTRICT Notes to the Financial Statements NOTE 1 -SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (continued) Restricted Assets Certain cash amounts are restricted to reflect tap payments and developer contributions that are being held for future capital improvements Developer Contributed Fixed Assets The Developer donated fi xed assets are valued at the ir estimated fair market value when the system is turned over to the District. At this point the D istrict is responsible to maintain the systems . Long-term Obligations Long-term obligation of the D istrict consists of two account payables . Note-2-Deposits The Colorado Public Deposit Protection Act, (POPA) requires that a ll units of local government deposit cash in eligible public depositories . Eligibility is determined by state regulators . Amounts on deposit in excess of federal insurance levels must be collateralized. The elig ible collateral is determ ined by POPA. POPA allows the institution to create a single collateral pool for all public funds . The poo l is to be maintained by another institution, or held in trust for all the uninsured public deposits as a group . The market value of the collateral must be at least equal to 102% of the aggregate uninsured deposits. Deposits are categorized to give an indication of risk assumed by the government at the end of the year. Category 1 includes deposits that are insured . Category 2 includes collateralized deposits held by the pledging institution's department or agent in the District's name . Category 3 includes uncollateralized, uninsured deposits . At December 31, 2006 the Districts deposits are categorized as follows: Cash with County Treasurer Categorized Deposits: Category 1 Deposits cover by Federal Insurance Category 2 Deposits collateralized under POPA agreement Totals -8- $ Bank Balance 1,256 200,000 1,746,533 $ 1.947,790 • • • ROARING FORK WATER & SANITATION DISTRICT Notes to the Financial Statements Note -3-lnvestments Colorado Statutes sp ec ify in which instruments the units of local Government may invest , these include : 1. Repurchase Agreements : Obligation of the United St ates or obligat ions unconditionally guaranteed by the United States. Obligation of the State of Colorado and most general obligations of units of local Governments. 2 . Federally insured mortgages and student loans . 3 . Participation w ith other local governments in pooled investment funds (trusts). These trusts are supervised by participating Governments , and must comply with the same restrictions on cash deposited and investments . Note-4-Risk Management The District is ex posed to various risks of loss related to property and casualty loss. The district joined with other Colorado Special Districts as a member of the Colorado Special Districts Property and Liability Pool. The pool is an organization created by intergovernmental agreement to provide property and general liability, automobile physical damage and liability, public official's liability, and equipment coverage to its members . The pool provides coverage for property claims up to the values declared and liability coverage for claims up to $1,000 ,000. The District pays annual premiums to the pool for liability and property insurance coverage . In the event aggregated losses incurred by the pool exceeded amounts recoverable from reinsurance contracts and funds accumulated by the pool, the pool may require additional contributions from members . Any excess funds that the pool determines are not needed for purposed of the pool may be returned to the members pursuant to a distribution formula -9- • • • ROARING FORK WATER & SANITATION DISTRICT Notes to the Financial Statements Note -5-Long-term Debt Accounts Payable to Developer: The District has agreements w ith the several developers to reimburse the costs of construction and installation of the sewer and water systems . Water Agreement: Pursuant to agreements between the Homeowner Association at Aspen Glen, L.B . Rose Ranch and the Roaring Fork Water & Sanitation District, $1,575 of each $3 ,000 water tap received by the District from customers within the their respective subdivision developments is to be reimbursed to the developers of that subdivision until the cost of the wholesale water facility is recovered by the developers to the best of the District's ability. Sewer Agreement: Pursuant to agreements between Homeowner Association at Aspen Glen, Coryell Ranch Company , and the Roaring Fork Water & Sanitation District, sewer taps collected from customers w ithin the Aspen Glen, Coryell Ranch and Midland Point developments are being retained by the District to be used for the expansion of the wastewater treatment facility necessary to accommodate Aspen Glen at build-out. Upon retaining 169 taps, $659, 100, the District will then resume reimbursing the developer until the cost of the wholesale facility is recovered by Aspen Glen to the best of the District's ability. L.B. Rose Ranch is being reimbursed $3,900 for each tap that is sold within the lronbridge development. Note-6-0ther Information Water Rights The District has received water rights in va r ious ditches and wells from the developer of the District. The rights were either included in the purchase price of the original ranch property and have been subsequently estimated, or have been decreed through court action and the costs involved have been capitalized . -10- • • • ROARING FORK WATER & SANITATION DISTRICT Notes to the Financial Statements Note-7-Tabor Amendment In November 1992, Colorado voters approved Amendment 1 to the State Constitution which is comm<;>nly known as the Ta xpayers ' Bill of Rights or the Tabor Amendment. The amendment applies to all units of local government and limits taxes, spending, revenue, and multi-year debt (e xcepting bond refunding to lower interest rates and adding employees to pension plans). The amendment does not apply to units of local government that are defined as an "Enterprises". The amendment defined the District's year ended Decemb~r 31, 1996 as the initial base year for purposes of defining compliance with the amendment. Increases in revenues from one year to the next are limited by local growth and inflation . The amendment defines inflation and local growth. Excess income must be refunded to taxpayers on some sort of reasonable basis unless the voters were to approve retention of the revenue by the District. The District in May 1994 posed two questions to the voters of the District. The first was to allow the District to levy property taxes not to exceed $120,000 and the second was to allow the District to collect, spend all debt proceeds incurred by the District, and valorem taxes collected for debt payments, and revenue from any other source form which the debt is payable. The ballot questions were approved by the voters . The District believes that it is in compliance with the provisions of TABOR, as it is currently understood . Many of the provisions may not become fully understood without judicial review. Note -8-Contributed Capital The contributed capital (plant investment fees) for 2006 consisted of$ 276,268 in water tap fees and $ 350,580 in sewer tap fees . -11- • • • ROARING FORK WATER & SANITATION DISTRICT Notes to the Financial Statements Note-9-Capital Assets A summary of changes in fixed assets follows : Balance Dece~ber 31, Balance December 31, 2005 Additions Deletions 2006 Land & improvements $ 323,325 Source of Supply 1,077,132 Water plant & distribution 2,735 ,697 Sewer plant & d istribution 4, 107,265 Equipment 50,935 Furniture & fixtures 23 967 8 ,318,321 Accumulated depreciation 1 362 683 NET PROPERTY AND EQUIPMENT $ 6.955.638 $ 24 ,250 146 ,393 15,665 46,4 73 1 346 $ 234.127 $ $ $ 323,325 1,077,132 2,735,697 4,107,265 50,935 23.967 8,318,321 1,576,588 $ 6,924 ,073 Depreciation for the year ended computed on the straight-line basis over estimated useful lives of 5-40 years was$ 213,904 . Note-10-Prior Period Adjustment An error was found in the 2005 financial statements in the amount of$ 34,998 . The error effects Developers accounts payable which was recorded twice . The following should have been reported on the December 31, 2005 Balance Sheet. Before: Developers payable@ December 31, 2005 $ 3,001,071 After: Developers payable@ December 31, 2005 3 ,036,069 Difference $ 34 ,998 -12- • • • 22.5(2)(f) Schedule A schedule in the fom1 of a timeline is shown in fi gure 7 . The process d esign report application will be submitted in February of 2008 . SGM will prepare design drawings and contract documents for 6 months , from October 2007 through March 2008 , resulting in approval by CDPHE by May, 2008. The bid process will commence in mid-June and construction is anticipated to be comp leted in May 2009. Es tim at ed C on stru ctio n T im e The estimated time to construct the proposed faci lities from the start of construction to start- up is 12 months Es tim ated S ta rt-Up D a te The predicted start-up date is June 2009 . 1:\1996\96059 \A -82 WWTF Ex pansio n Pl annin g\2 -WWTF Ex pansi o n Perm ittin g\Reg 22 Fin al.d oc Pag e 9of12 • • • ·,~ ~ ... 1--v"' '<.. .. ~.,. ~ "'• -t.9~ ~ " .. ~ ~ ,.., .. ~ .......... ?~ -t,.'?"o "'"9~ ..... '·~,~ ~._ •,-:.,,. -1'"".;. ' '• ·~ ~.,~ ''> ~o ''\>,, '+'\. "'"1..; .. ._, " "' ""· ] ~~ t f ~ ~~ =~ ~, ~} ' fe ,. ,: ~ ?, ~· r i Ji Figure 7 -WWTF Expansion Schedule ~ ~ 3 ~ ! ~ ~ ~ ~ w ~ '~ ~ ~ ~ :; :: ~ -r ~ ~ ' ' i r:' ~ .~· • ~ '.s:J I'-\(.! C'I .......... -.... R N f:I ~ (ti ~l ~ ~ ~ I :\1996\96059 \A-82 WWTF Ex pa ns ion Plannin g\2 -WWTF Expansion Permitt in g\Rc g 22 Fi na l.d oc Page 10of12 • • • 22.5(3) Soils Report The soils report from the first phase of construction that was done in 1994 is attached . 1:\1 996 \9605 9\A -82 WWTF Expa ns ion Plannin g\2 -WWT F Ex pans ion Permittin g\Reg 22 Fin al.doc Page 1 1 ofl2 • • • HEPWORTH-PAWLAK GEOTECHNICAL, !Ne. 5020 Road 154 Glenwood Springs, CO 81601 Fax 303 945-8454 Phone 303 945-7988 SUBSOIL STUDY FOR FOUNDATION DESIGN PROPOSED WASTE WATER TREATMENT PLANT ASPEN GLEN DEVELOPMENT GARFIELD COUNTY, COLORADO. JOB NO. 193 174-5 JUNE 9, 1994 PREPARED FOR: THE ASPEN GLEN COMPANY ATTN:. JIM WOODS 555 EAST DURANT, SUITE 4A ASPEN, COLORADO 81611 • • • HEPWORTH-PAWLAK GEOTECHNICAL, INC. June 9, 1994 The Aspen Glen Company Attn: Jim Woods 555 East Durant, Suite 4A Aspen, Colorado. 81611 5020 Road 154 Glenwood Springs, CO 81601 Fax 303 945-8454 Phone 303 945-7988 Job No. 193 174-5 Subject: Subsoil Study for Foundation Design, Proposed Waste Water Treatment Plant, Aspen Glen Development, Garfield County, Colorado. Gentlemen: As requested, we have conducted a subsoil study for the proposed treatment plant at the subject site. · Subsurface conditions encountered in the exploratory borings drilled in the proposed development area consist of 1/2 to 4 feet of topsoil and soft silt above dense sandy gravel and cobbles with boulders. Weathered siltstone bedrock of the Eagle Valley Evaporite was encountered at 10 to 14 feet. Groundwater was encountered in the borings between 1 1/2 and 5 feet below the ground surface. The water is likely perched on the bedrock and fed by the upslope irrigated fields and the Glenwood Ditch. The proposed plant facilities can be founded on spread footings or structural slabs placed on the natural gravel or siltstone and designed for an allowable bearing pressure of 3,000 psf. Pre-excavation dewatering will probably be required. An intercept trench drain should be constructed around the uphill side of the facilities and the Glenwood Ditch should be lined to reduce the long term groundwater impact on the project. The report wruch follows describes our investigation, summarizes our findings, and presents our recommendations. It is important that we provide consultation during design, and field services during construction to review and monitor the implementation of the geotechnical recommendations. If you have any questions regarding tills report, please contact us. Sincerely, HEPWORTH-PAWLAK GEOTECHNICAL, INC. ~A-{JJ.k__ Steven L. Pawlak, P .E. Rev. By: DEH SLP/ro cc: Schmueser Gordon Meyer -Attn: Jeff Simonson I I I I • • • TABLE OF CONTENTS PURPOSE AND SCOPE OF STUDY PROPOSED CONSTRUCTION . SITE CONDITIONS . . GEOLOGIC SETTING . FIELD EXPLORATION . SUBSURFACE CONDITIONS ENGINEERING ANALYSIS . DESIGN RECOMMENDATIONS . FOUND A TIO NS . . . . . FOUNDATION AND RETAINING WALLS. FLOOR SLABS . . . . . . . . . . . . . UNDERDRAIN SYSTEM . SITE GRADING . . . . SURF ACE DRAINAGE . LIMITATIONS . . . . . . .. FIGURE 1 -LOCATION OF EXPLORATORY BORINGS FIGURE 2 -LOGS OF EXPLORATORY BORINGS FIGURE 3 -LEGEND AND NOTES FIGURE 4 -GRADATION ANALYSES TEST RESULTS TABLE I -SUMMARY OF LABORATORY TEST RESULTS . 1 . 1 .2 .2 . 3 . 3 .4 .4 .4 . 5 .7 .7 . 8 . 8 . 9 • • • PURPOSE AND SCOPE OF STUDY This report presents the re sults of a subsoil study for the proposed waste water treatment plant to .be located near the Aspen Glen Development, Garfield County, Colorado. The project site is shown on Fig. 1. The purpose of the study was to develop recommendations for the foundation design. The study was conducted in accordance with our proposal for geotechnical engineering services to The Aspen Glen Company, dated January 20, 1994. A previous subsoil study for the treatment plant was conducted by Chen-Northern under Job No . 4-112-92, dated May 28, 1993. ' ' A field exploration program consisting of exploratory borings was conducted to obtain information on sub surface conditions. Samples obtained during the field exploration were tested in the laboratory to determine engineering characteristics of the on-site soils and rock. The results of the field exploration and laboratory testing were analyzed to develop recommendations for foundation types, depths and allowable pressures for the proposed building foundation . This report summarizes the data obtained during this study and presents our conclusions, design recommendations and other geotechnical engineering considerations based on the proposed construction and the subsoil conditions encountered. PROPOSED CONSTRUCTION The waste water treatment plant site will cover an area of about one acre. The proposed treatment facilities will include relatively small buildings and below grade structures such as aeration basin, aerobic digester, clarifier and chlorine contact tank. Excavation depths are expected to range between 10 to 15 feet. Foundation loadings should be relatively light and carried by structural slabs for the below grade structures. If building loadings, location or grading plans change significamly from those described above, we should be notified to reevaluate the recommendations contained in this report. • • • -2 - SITE CONDITIONS The site consists of an irrigated grass field on a flat topographic bench. The terrace slopes are about 6 to 8 feet high on the downhill east side and 10 to 20 feet high on the uphill west side . Existing out buildings are located along the top of the downhill terrace slope. The Glenwood Ditch, which is earthen and was flowing at the time of ·our field work, borders the toe of the uphill terrace slope. Elevation difference across the plant area is about 4 feet. A marshy linear depression about 1 to 2 feet deep is located just north of the plant area. The ground surface was soft which made access difficult with the truck drill rig . The Roaring Fork River is located a few hundred feet northeast of the site and about 12 to 15 feet lower in elevation. A gravel quarry is located on the next bench above the site to . the southwest . GEOLOGIC SETTING The site is located in the first gravel terrace deposit above the modem valley alluvium of the Roaring Fork River. Shale consisting of siltstone and gypsum of the Eagle Valley Evaporite underlies the site at about 10 to 15 feet based on the borings. The rock contains lenses and layers of gypsum and other anhydrites that are know to have dissolved and caused surface subsidence under certain environmental conditions. The borings did not encounter voids in the subsoils or rock. Sinkholes were not observed on the property. The shallow depression to the north of the plant site could represent a broad area subsidence but appears to be inactive. The potential for future sinkhole development at the site appears low. The excavations for the structures should be closely observed for signs of voids . H-P GEOTECH ' • • - 3 - FIELD EXPLORATION The field t:;xploration for the project was conducted on May 25, 1994. Three exploratory borings were drilled at the locations shown on Fig. 1 to evaluate the subsurface conditions. The borings were advanced with 4-inch diameter continuous flight augers powered by a truck-mounted CME-55 drill rig. The borings were logged by a representative of Hepworth-Pawlak Geotechnical, Inc. Samples of the subsoils were taken with a 1 3/8-inch I.D. spoon sampler. The sampler was driven into the subsoils and bedrock at various depths with blows from a 140-pound hammer falling 30 inches. This test is similar to the standard penetration test described by ASTM Method D-1586. The penetration resistance values are an indication of the relative density or consistency of the subsoils and rock. Depths at which the samples were taken and the penetration resistance values are shown on the Logs of Exploratory Borings, Fig. 2. The three previous borings which were drilled by Chen-Northern in the area are also shown. The samples were returned to our laboratory for review by the project engineer and testing. SUBSURFACE CONDITIONS Graphic logs of the subsurface conditions encountered at the site are shown on Fig. 2 . The subsoils consist of about 1/2 to 4 feet of topsoil and soft sandy _ silt overlying relatively dense, slightly silty sandy gravel and cobbles with boulders. Drilling in the dense gravel with auger equipment was difficult due to the cobbles and boulders and drilling refusal was encountered in the deposit. Below the gravel alluvium at depths of 10 to 14 feet, weathered siltstone was encountered to the maximum depth drilled of 40 feet. The rock contains harder and softer zones but generally appears to be medium hard. No indications of voids were encountered. The rock is typically fractured and broken and of poor quality . H-P GEOTECH • • • 4 •' -- Laboratory testing performed on samples obtained from the borings included natural moisture content, gradation analyses and liquid and plastic limits.: Results of gradation analyses performed on small diameter drive samples (minus 1 112-inch fraction) of the natural coarse granular soils are shown on Fig. 4. The liquid and : plastic limit tests indicate the upper silt and siltstone ::~e low plasticity. The laboratory testing is summarized in Table I. Free water was encountered between 1 112 and 5 feet in the borings and the subsoils were highly moist to wet. The water level can likely rise to near the ground surface from the uphill field irrigation and ditch leakage. ENGINEERING ANALYSIS The subsoils consist mainly of dense gravel terrace deposits which should support moderately loaded spread footing or mat foundations. The underlying siltstone is weathered with the consistency of a hard clay or silt and also suitable for footing or mat support provided the foundation excavations are kept dry. Pre-excavation dewatering should be provided for all below grade structures. An area trench drain that perimeters the uphill side of the excavations or sumps that extend into the bedrock should be possible dewatering methods. Extensive underdraining will be needed to protect the structures against hydrostatic pressures. The Glenwood Ditch may also need to be lined to help control groundwater impact. DESIGN RECOMMENDATIONS FOUND A TIO NS Considering the subsoil conditions encountered in the exploratory borings and the nature of the proposed construction, we recommend the structures be founded with spread footings or structural slabs bearing on the natural granular soils or on bedrock. H-P GEOTECH • • • ~~----------------................... . - 5 - The design and construction criteria presented below should be observed for a spread footing foundation system. 1) Footings placed on the undisturbed natural granular soils or bedrock should be designed for an allowable soil bearing pressure of 3,000 psf. Based on experience, we expect settlement of footings designed and constructed as discussed in this section will be about 1 inch or Jess. 2) The footings should have a minimum width of 16 inches for continuous walls and 2 feet for isolated pads. 3) Exterior footings and :footings beneath unheated areas should be provided with adequate soil cover above their bearing elevation for frost protection. Placement of foundations at least 36 inches below exterior grade is typically used in this area . 4) Continuous foundation walls should be reinforced top and bottom to span local anomalies such as by assuming an unsupported length of at least 10 feet. Foundation walls acting as retaining structures should also be designed to resist lateral earth pressures as discussed in the "Foundation and Retaining Walls" section of this report. 5) The topsoil, silt and any loose or disturbed soils should be removed and the footing bearing level extended down to relatively dense natural granular soils or bedrock. Water seepage should be collected outside of the footing area so that the excavation bottom is dry. We should observe the adequacy of the dewatering before concrete placement. 6) A representative of the soil engineer should observe all footing excavations prior to concrete placement to evaluate bearing conditions. FOUNDATION AND RETAINING WALLS Foundation walls and retaining structures which are laterally supported and can be expected to undergo only a slight amount of deflection should be designed for a H-P GEOTECH • • • - 6 - lateral earth pressure computed on the basis of an equivalent fluid unit weight of 50 pcf for backfill consisting of the on-site granular soils . Silt and topsoil should not be used as backfill except for the top 2 feet. All foundation and retaining structures should be designed for appropriate •' hydrostatic and surcharge pressures such as adjacent footings, traffic, construction materials and equipment. The pressure recommended above is for a drained condition behind the walls and a horizontal backfill surface. If the water level behind the wall is allowed to rise, the total unit lateral pressure imposed on the wall (soil plus hydrostatic) should be taken as 95 pcf. Underdrains would be needed to control hydrostatic pressure buildup behind walls. Backfill should be placed in uniform lifts and compacted to at least 95 3 of the maximum standard Proctor density at a moisture content near optimum. Care should be taken not to overcompact the backfill or use large equipment near the wall since this could cause excessive lateral pressure on the wall. Some settlement of deep foundation wall backfill should be expected even if the material is placed correctly and could result in distress to facilities constructed on the backfill. We have assumed relatively free-draining granular soils such as the on-site gravels for backfilling foundation walls and retaining structures because their use results in lower lateral earth pressures and the backfill can be incorporated into the underdrain system. Subsurface drainage recommendations are discussed in more detail in the "Underdrain System" section of this report. Granular wall backfill should contain less than 15 3 passing the No. 200 sieve and have a maximum size of 6 inches. The lateral resistance of foundation or retaining wall footings will be a combination of the sliding resistance of the footing on the foundation materials and passive earth pressure against the side of the footing. Resistance to sliding at the bottoms of the footings can be calculated based on a coefficient of friction of 0.5 for gravel and 0.3 for siltstone . Passive pressure against the sides of the footings can be calculated using an equivalent fluid unit weight of 200 pcf. The coefficient of friction H-P GEOTECH • • • - 7 - and passive pressure values recommended above assume ultimate soil strength and a submerged condition. Suitable factors of safety should be included in the design to limit the strain w~ich will occur at the ultimate strength, particularly in the case of passive resistance.· Fill placed against the sides of the footings to resist lateral loads should be a granular material compacted to at least 95 % of the maximum standard Proctor density at a moisture content near optimum. FLOOR SLABS The natural gravel soils below the topsoil and soft silt are suitable to support lightly to moderately loaded slab-on-grade construction. To reduce the effects of some differential movement, non structural floor slabs should be separated from all bearing walls and columns with expansion joints which allow unrestrained vertical movement. Floor slab control joints should be used to reduce damage due to shrinkage cracking . The requirements for joint spacing and slab reinforcement should be established by the designer based on experience and the intended slab use. A minimum 4-inch layer of free-draining gravel should be placed beneath slabs to facilitate drainage. This material should consist of minus 2-inch aggregate with at least 503 retained on the No. 4 sieve and less than 2 3 passing the No. 200 sieve. All fill materials for support of floor slabs should be compacted to at least 95 % of maximum standard Proctor density at a moisture content near optimum. Required fill can consist of the on-site gravels devoid of vegetation, topsoil and oversized rock. UNDERDRAIN SYSTEM Free water was encountered near the ground surface. Seasonal fluctuations in the water level can be expected. We recommend below grade construction, such as retaining walls, crawl space and tanks or basins, be protected from hydrostatic pressure buildup by an underdrain system. The designers may elect to design the structures to resist hydrostatic uplift forces. H-P GEOTECH • • • - 8 - The underdrain system should consist of drainpipe placed in the bottom of the wall backfill surrounded above the invert level with free-draining granular material. The drain should be placed at least 1 foot below lowest adjacent finish grade and sloped at a minimum 1/2 % to a suitable gravity outlet. The underslab gravel should connect to the perimeter drain. Free-draining granular material used in the underdrain system should contain less than 2 % passing the No. 200 sieve, less than 503 passing the No. 4 sieve and have a maximum size of 2 inches. The drain gravel backfill should extend to within about 2 feet of final ground surface. The invert level of the drains will likely be controlled by the gravity daylight elevations since the flood level of th.e river is only about IO feet below the site. SITE GRADING We recommend pre-excavation dewatering for all below grade structures. Slope stability and poor bearing conditions will be a concern if the dewatering is not adequate. The contractor should provide us a plan for dewatering and excavation before starting construction. We expect that an intercept trench drain and/or sumps that extend into the underlying bedrock can be used for area dewatering. Additional trenches and sumps will likely be needed inside the excavations. Sheet piling may be feasible to provide temporary excavation slope bracing. The piling should be driven into the bedrock. Driving conditions will be difficult in the gravel and shallow refusals may be encountered. SURF ACE DRAINAGE The following drainage precautions should be observed during construction and maintained at all times after the facilities have been completed: 1) Inundation of the foundation excavations and underslab areas should be avoided during construction . H-P GEOTECH • • • 2) -9:.. Exterior backfill should be adjusted to near optimum moisture and compacted to at least 95 3 of the maximum standard Proctor density in pavement and slab areas and tp at least 903 of the maximum standard Proctor density in landscape areas. 3) The ground surface surrounding the exterior of the buildings should be sloped to drain away from the foundation in all directions. We recommend a minimum slope of 6 inches in the first 10 feet in unpaved areas and a minimum slope of 3 inches in the first 10 feet in paved areas. Free-draining wall backfill should be capped with about 2 feet of the on-site finer graded soils to reduce surface water infiltration. 4) Roof downspouts and drains should discharge well beyond the limits of all backfill . LIMITATIONS This report has been prepared in accordance with generally accepted geotechnical engineering principles and practices in this area at this time. We make no other warranty either expressed or implied. The conclusions and recommendations submitted in this report are based upon the data obtained from our exploratory borings drilled at the locations indicated on Fig. 1, the proposed type of construction and our experience ill the area. Our findings include interpolation and extrapolation of the subsurface conditions identified at the exploratory borings and variations in the subsurface conditions may not become evident until excavation is performed. If conditions encountered during construction appear different from those described in this report, we should be notified so that re-evaluation of the recommendations may be made. This report has been prepared for the exclusive use by our client for design purposes. We are not responsible for technical interpretations by others of our H-P GEOTECH • • • -10 - information. As the project evolves, we should provide continued consultation and field services during construction to review and monitor the implementation of our recommendations, and to verify that the recommendations have been appropriately interpreted. Significant design changes may require additional analysis or modifications ,·' to the recommendations presented herein. We recommend on-site observation of excavations and foundation bearing strata and testing of structural fill by a representative of the soil engineer. Sincerely, HEPWORTH-PAWLAK GEOTECHNICAL, INC. ~1-~~ Steven L. Pawlak, P .E. \\\\lllllllllllllif11, Reviewed By: ~,,~~\)O P.EGts/'?q~ s <:::;~ ••• •••• {-9.. ~ U~. ~-.,,;.·~~\. HA_?· •• ~\ • ~ ~-s: SLP/ro . ~~ $ {Q 24443 : f Daniel E. Hardin, P. --·..o~0/ro/9y /~/ ~ .A'\ .•Ji;~ ~ ··~t::: ~S.t> .... ..,~~~,,.,~~ ~;Y10NAl " '1\-.,v-· . .,."'"'"'111111\\\\\~ H-P GEOTECH • • • f Boring B-11-93 Approximate Scale 1" = 80' Facilities (typ.) Gravel Quarry LEGEND: e Exploratory Boring Drilled for This Study O Exploratory Boring Drilled by Chen-Northern, Inc., Job No. 4 112 92, Dated May 28, 1993 193 174_5 I HEPWO .. TH-PAWLAK GEOiECHNICAL, Inc. 0 Boring B-9-93 Location of Exploratory Borings Fig. 1 • • • . I r--0 10 ~~ 15 ..s:::: .+.) Cl. QJ Cl I 20 25 30 35 40 Boring 1 Boring 2 Borin5 3 B-9-93 B-10-93 B-11-93 Elev=5965 1 Elev =5963 1 Elev= 963' Elev=5964' Elev=5963 1 Elev=S964' ,..,........ ·-~ ... 0 /12 .~C=20 20/1241 ff.:<t VJ W~=~ •.·. · ·· LL=24 a:,r + = 7 ~o · 48/12 ~ ~ -200=56 r-0 = 9 l,> ;,~ P I = 4 }•4=65 -200=4 58/12 ~;~ t~~3s112 ·p:· 4 3 I 8, 2 o Io 5 +4=61 -200=7 20/5, 20/0 ~46/12 WC=9.6 l6~ -200=44 lllo21 PI=6 -:- 70/12 Note: Explanation of symbols is shown on Figure 3. 10 15 . 20 25 30 35 40 j~ 3i HEPWORTH-PAWLAK 1 9 3 1 7 4 - 5 I G!OTECHNICAL, Inc. Logs of Exploratory Borings Flt. 2 • • • LEGEND: § Ed ~ . . I I ~· 20/12 - T TOPSOIL; organic sandy silt, dark brown . SILT (ML); clayey, sandy, soft, wet, brown . GRAVEL (GM -GP); sandy, cobbles with boulders, dense, wet, brown, rounded rock. WEATHERED SHALE-SILTSTONE AND GYPSUM; clayey, variable, firm to medium hardness, moist, grey, Eagle Valley Evaporite. 1 1 /2" PVC pipe i nstalled to depth shown. Hatched part is slotted. Drive sample; standard penetration test (SPT), 1 3/8-inch l.D. split spoon sample, ASTM D-1586. : Drive sample blow count; indicates that 20 blows of a 140-pound hammer falling 30 inches were required to drive the SPT sampler 12 inches. Depth at which free water was encountered and number of days after drilling measurement was taken . Deoth at which boring ·caved when checked on June 8, 1994. Practical refusal on boulders. NOTES: 1 . The exploratory borings was drilled on May 25, 1994 with a 4-inch diameter continuous flight power auger. 2. Locations of the exploratory borings was measured approximately by pacing from features shown on the site plan provided. 3. Elevations of the exploratory borings were obtained by interpolation between contours on the site plan provided. Logs of exploratory borings are drawn to depth. 4. The exploratory boring locations and elevations should be considered accurate only to the degree i mplied by the method used. 5. The lines between materials shown on the exploratory boring logs represent the approximate boundaries between material types and transitions may be gradual. 6. Water level readings shown on the logs were made at the time and under conditions indicated. Fluctuations in water level may occur with time . 7. Laboratory Testing Results: WC = Moisture Content (%) + 4 = Percent retained on No. 4 sieve -200 = Percent passing No. 200 sieve LL = Liquid Limit (%) Pl = Plasticity Index(%) l HEPWORTH-PAWLAK I LEGEND AND NOTES 193 174-5 G!OTECHNICAL, Inc. Fig. 3 • • • H YOn OM E T En AN AL YSIS SI E V E ANAL YSIS I IME llE.AUINuS U.S. Sl A NUAllU S llllES (;LE/\11 !iUU.l'llE. Of'ENINuS 2• ••n . 1 Hn . •tn 45 MIN 15 MIN. f;O MIN. 19 U1N. • U1N. 1 MIN. '71WI "1 00 '!in ·•n ·~o ·111 f ·n .. ..... ..... ·~-:r 5•11'" fl'". 0 90 10 00 20 __._ 70 , __ _ I~-""-JO Cl 0 ~ 60 "' "' .. ... ~ I-z .. ~ 4'0 w ... w .ooz 1 I-I• w so"' I----7. ... '"° :i •• ... f---4---f--i ----;---..--+------+~~ :==l" t=::t= t==1~ , __ _ JO 10 ;>() ---<----! j . llO 10 o_ .Ulll .U02 9~ J..o:::r:J. .UJ/ .u1• .1•9 .2'JI I .~!XI .•? 2.0 1.1!1 2.J8 •.IG .005 .009 .U19 DIAMETER OF J'>/\RTICLE IN MILLIMF.TERS Clol'Y 1'0 SILT 5 1\Nll GllAVl:l FI NE U E IJ IUM CU /\llSE FINE COAll5C: COBOLES GRAVEL 65 % SANO 31% SILT ANO CLAY 4.,. LIQUID LIMIT 'Yo PLASTICITY I NDL:."< %o SAMPLEOF sandy gr a vel FROM Bor i ng 1 @ 4' & 9' Combined HYOnO MET ER A N ALYSIS SIEVE ,\NAL YSIS !IME. HE.AUINGS 2• 1<11 . 7 HR . ·~MIN 15 UIN. 60 MIN. 19 MIN. 4 MIN. I MIN 90 Bil 701----i· 0 ~ 60 "' "' .. Q. I-so z w u n: •O w Q. JO :10 10 0 .001 .002 ~==:.:.j ·1--+===l I ' l--1· ,___. .au:'> .008 .019 .UJ7 Clol'Y 1'0 Sil T GRAVEL 61 'Jlr LIQUID LIMIT U.S. :; I l\NOAllU :;r:IHC:S '100 • 100 ·10 "!in ·•n ·~n ·1n 1 ·n .. l ~ ~ ·i-r- ~! I ;~===1=;8 : '! . '-i l '--+-; _;-! l !-!~ f---4-----f~ =::i=i ==!:l . ..1 -~--i----'­ -t-, __ _ >--1-I ~ ·--- i---t- .014 .1•9 .297 I .~!JO 1.19 12.:lll •.I& .•2 2.0 DIAMETER OF P/\RTICLE IN MILLIMETERS S ANn CLEAR SQUol'llE OPENINGS ..... ,.,. ,.,... 9.£! 11.1 Ja.I :i-• s· r.-s" --· 10 '-0 I Cl '°~ ::( ·-"' 50« .... z w GOU "' •• ... ---"-' 70 1&.2 80 90 100 127 ' 2Cio 152 GRAVEL I f1NE I MEDIUM lco/\nsel flNE I COAnse jCOBBLES SANO .. 32%-SILT AND Cl.J\Y Pt.ASTIClTY INDEX 7~ ... SAMPLE OF sandy grave 1 FROM Boring 2@ 5 1 & 8 1/2 1 Combined 193 174-5 HE?WORTH-PAWLAK GEOTECHNICAL. Inc. GRADATION TEST RESULTS Fig. 4 • • • HEPWORTH-PAWLAK GEOTECHNICAL, INC. JOB NO. 193 174-5 TABLE I SUMMARY OF LABORATORY TEST RESULTS SAMPLE LOCATION NATURAL NATURAL GRADATION PERCENT A TTERBERG LIMITS UNCONFINED BORING DEPTH MOISTURE DRY GRAVEL SAND PASSING LIQUID PLASTIC COMPRESSIVE SOIL OR ll••tl CONTENT DENSITY 1%1 (%) NO . 200 LIMIT INDEX STRENGTH BEDROCK TYPE 1%) (pc!) SIEVE (%) 1%) (PSF) 1 4&9 65 31 4 sandy gravel (combined) 2 5 & 8 1 /2 61 (combined) 32 7 sandy gravel I - 3 10 9.6 44 21 6 weathered siltstone-claystone ........ ..... --~ "' ... ~ .. ·- • • • 22.5(4) Review by other agencies 22.5(4)(a) Review comments by the management agency if necessary Not applicabl e. 22.5(4)(b) Review comments by the county if necessary The re view comments ar e attach ed. 22.5(4)(c) Review comments by the city or town if necessary Not applicab le. 22.5(4)(d) Review comments by the local health authority Not app licabl e. 22 .5(4)(e) Review comments by the water quality planning agency Not applicab le . 1:\ 1996 \96059\A -82 WWTF Expa nsion P lan nin g\2 -WWTF Ex pa ns ion Permittin g\Reg 22 Fi nal.doc P age 12of 12 • I:\ 1996\96059\BM.dwg Saved: Fri, 19 Oct 2007 9:53am Plotted: Fri, 19 Oct 2007 9:59am clehrman (/) () l'1 ::r: z ~ G'l c z fTJ (/) l'1 fTJ l'1 ::0 ;o ~· (/) G) (/) 0 ::0 c 0 ;o 0 < z l'1 -< 0 ~ :0 (/) ~ ::0 Q G,' ID~= ~ ~ ~!i ()) ;;i _z -:<::!: 0 0 ID8 . CD~ ~o ~ § 0 _:_~I m ~ O~'!J -o Qz::u ()0 .j>Cll'l o-Ull'l ID --i iD '.J ~S'~ '-lg re g ID(()~~ W N '-ll> .!> U1 QO N ID • -o 0 • Ol IDOlO U1 '.J .!>- W N UlQl ~ -.J Uio ID- .!> ()) N w ,,...,. ..,: ~ a >- o9o9 $ (t • ~ ::;-i ~ ~ ~ <b ........ \)-~ Q <b ........ ...., ;:;: 3 Q \)- <b ~ (!)-:::i ........ ::::::: (/) ~ ~ :::::.: Q :::i 8--........ ::::i · I.(} (/) RFWSD WWTF .... 1 MILE RADIUS MAP • I \ 0 '1 ~ 8 > 0 ~ ::c: -"' n 8 0 (fl n > r-4 M ... 8 0 Job No. 96059A-82 Drawn by: MMM Date: 09 07 Appr. by: CLL File: B .d