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An Employec Owncd Compony
5020 County Road 154
Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email : kaglenwood@kumarusa.com
www.kumarusa,com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
June27,2022
RM Construction
Attn: Blake Piland
5030 Road 154
Glenwood Springs, Colorado 81601
blake@buildwithrm. com
Project No.22-7-425
Subject: Observation of Excavation, Proposed Residence, Lot FW-8, Aspen Glen,
303 Golden Bear, Garfield County, Colorado
Gentlemen:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on June 15, 2022 to evaluate the soils exposed for foundation support. The findings
of our observations and recommendations for the foundation design are presented in this report.
Hepworth-Pawlak Geotechnical (now Kumar & Associates) previously conducted a subsoil
study for design offoundations at the site and presented the findings in a report dated
June 30, 2014, Job No. 1 14 225A. The current observation was conducted in accordance with
our agreement for professional services with RM Construction dated June 14,2022.
The proposed residence appears about the same as described in the previous report and has been
design for spread footings placed on the natural soils and sized for an allowable bearing pressure
of 1,500 psf with the settlement risk mainly from post-construction bearing soil wetting.
At the time of our visit to the site, the foundation excavation had been cut in one level from 4 to
6 feet below the adjacent ground surface. The garage aÍea was close to the prior grade with little
cut. The soils exposed in the bottom of the excavation consisted of stiff to very stiff sandy silty
clay and had been compacted. Utility trenches in the southeast corner also exposed the clay soils
to 3 feet below the building cut depth (about 7 feettotal cut depth). Results of swell-
consolidation testing performed on a sample taken from the site, shown on Figure 1, indicate the
soils are slightly to moderately compressible under conditions of loading and wetting. The
laboratory test results are presented in Table 1. No free water was encountered in the excavation
and the soils were slightly moist.
The soil conditions exposed in the excavation are consistent with those previously encountered
on the site and suitable for support of spread footings designed for the recommended allowable
bearing pressrüe of 1,500 psf with the settlement potential. Loose disturbed soils in the footing
areas should be moistened and compacted or removed to expose the undisturbed natural soils.
Other recommendations presented in our previous report which are applicable, especially those
to keep the bearing soils dry, should also be observed.
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SAMPLE OF: Sondy Silty Cloy
FROM: Bollom of Excovolion Soulh Corner
WC = 6.7 %, DD = 91 pcf
ADDITIONAL COMPRESSION
UNDER CONSTANT PRESSURE
DUE TO WETTING
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22-7 -425 Kumar & Associates SWELL-CONSOLIDATION TEST RESULTS Fig. 1