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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
December 30, 2021
Last Ridge Development
Attn: Gary Manchester
1720 Wazee, #5D
Denver, Colorado 80202
gmanchester@lastridgedev.com
Project No. 21-7-164
Subject: Observation of Excavation, Proposed Residence and Garage, Lot 26, Stirling
Ranch, 0678 Schooner Lane, Garfield County, Colorado
Gentlemen:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on December 21, 2021 to evaluate the soils exposed for foundation support. The
findings of our observations and recommendations for the foundation design are presented in this
report. We previously conducted a subsoil study for design of foundations at the site and
presented our findings in a report dated March 12, 2021, Project No. 21-7-164.
The proposed residence is essentially the same as described in our previous report and has been
design to be supported on spread footings sized for the recommended allowable bearing pressure
of 2,000 psf.
At the time of our visit to the site, the foundation excavation for both buildings had been cut in
multiple levels from 2 to 18 feet below the adjacent ground surface. The steps in grade were
typically 2 to 4 feet and up to about 12 feet at the north end of the basement area. The soils
exposed in the bottom of the excavation consisted of highly calcareous sandy silt in basalt rock
fragments to boulder size. A few voids created by boulder removal had been backfilled with the
onsite silty soils. 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 pressure of 2,000 psf. Loose disturbed soils in the footing areas should be removed or
moistened and compacted. The bearing soils should be protected from frost and concrete should
not be placed on frozen soils. Other recommendations presented in our previous report which
are applicable should also be observed.
The recommendations submitted in this letter are based on our observation of the soils exposed
within the foundation excavation and the previous subsurface exploration at the site. Variations
in the subsurface conditions below the excavation could increase the risk of foundation