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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
October 9, 2023
Jose Godina
P. O. Box 41
Basalt, Colorado 81621
prietogodina20@gmail.com
Project No. 21-7-855.01
Subject: Observation of Excavation, Proposed Main Residence, Lot 3, Ruiz Minor
Subdivision, County Road 346, near Silt, Garfield County, Colorado
Dear Jose:
As requested, a representative of Kumar & Associates observed the excavation at the subject site
on September 21, 2023 to evaluate the soils exposed for foundation support. The findings of our
observations and recommendations are presented in this report. The services are supplemental to
our agreement for professional services to you dated February 11, 2022.
We previously conducted a subsoil study for design of foundations at the site and presented our
findings in a report dated February 15, 2022, Project No. 21-7-855. The proposed construction is
similar to that assumed for our previous report. The main residence is located in the area of our
Boring 2 for that study. The building has been designed to be supported on spread footings using
an allowable soil bearing pressure of 1,500 psf, as recommended with some risk of settlement.
At the time of our site visit, the foundation excavation which was essentially complete had been
cut in one level from about 1 to 3 feet below the adjacent ground surface. The soils exposed in
the bottom of the excavation consisted of medium dense, silty clayey sand. Results of swell-
consolidation testing performed on samples taken from the site, shown on Figure 1, indicate the
soils are moderately compressible under conditions of loading and wetting. No groundwater was
encountered in the excavation and the soils were 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 1,500 psf. The risk of settlement is primarily if the bearing soils were to
become wetted and precautions should be taken to prevent wetting. Prior to the footing
construction, all loose disturbed soils should be removed to expose the undisturbed natural soils
and the subgrade compacted. 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
movement. We should be advised of any variations encountered in the excavation conditions for
possible changes to recommendations contained in this letter.
Kumar & Associates