HomeMy WebLinkAbout09.0 Past Referral Comments from CGSRGKMBK FAMILY LLC AND FRANCES BETTS
APPLICATION FOR BASIC CORRECTION EXEMPTION
RESPONSE TO SUBMITTAL REQUIREMENT 9.
The Applicants have attached Colorado Geological Survey's comments dated April 17, 2018.
COLORADO GEOLOGICAL SURVEY
1841 19"' Street
Golden, Colorado 80401
April 17, 2018
Patrick Waller
Garfield County
Community Development Department
108 8th Street, Suite 401
Glenwood Springs, CO 81601
Subject: RGKMBK Family LLC and Frances Betts Minor Subdivision
File Number M1SA-02-18-8607; Garfield County. CO; CGS Unique No. GA -180006
Location:
Section 18,
T7S, R87W of the 6th P.M.
39.4464, -107.159
Karen Berry
State Geologsl
Dear Mr. Waller:
Colorado Geological Survey has reviewed the above -referenced minor subdivision referral. 1 understand the
applicants seek a legal, two -lot subdivision of approximately 35 acres located at 7201 and 7202 County Road
100, in the Missouri Heights area northeast of Carbondale. Both proposed lots are currently improved with
single-family residences, onsite wastewater systems, and a shared well. CGS has no objection to approval of
the two -lot minor subdivision application as submitted.
According to Garfield County geologic hazard mapping, the site is located within an area of "Low hazard,
expansive or corrosive soil, soil creep, PUS 'potentially unstable slopes]." Since the site does not contain
significant slopes, the soil creep and PUS hazards are probably not applicable. However:
Subsidence hazard. According to available geologic mapping (Geologic Map of the Carbondale Quadrangle,
Garfield County, Colorado: CGS, 2008, Map Series 36, scale 1:24,000), the site is underlain by collapse
deposits, formed in response to differential collapse resulting from dissolution of underlying evaporite.
Sinkholes, subsidence and ground deformation due to collapse of solution cavities and voids are an ongoing
concern in this area. Ground subsidence related to the dissolution of evaporate bedrock is an unpredictable
risk that should not be ignored.
The applicant, owners, and potential purchasers should be advised of the sinkhole potential, since early
detection of building distress and timely remedial actions are important factors in reducing the cost of
building repairs should an undetected subsurface void start to develop into a sinkhole.
Thank you for the opportunity to review and comment on this project. if you have questions or need further
review, please call me at (303) 384-2643, or email carlson@mines.edu.
Sincerely,
Jillarlson, C.E.G.
Engineering Geologist
CA -18414)6_1 RGKMBK Family LLC and Frances Betts Moor Subdivision
3-25 PM, 04/17/2018