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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
January 17, 2023
Revised March 31, 2025
Drs. Carol & John Wise
1815 Forest Grove Road
Lucas, Texas 75002
docjohn@wiseorthodontics.com
Project No. 20-7-670
Subject: Observation of Excavation, Proposed Residence, 0044 Kingbird Drive, Lot 19,
Filing 9, Elk Springs, Los Amigos Ranch, Garfield County, Colorado
Dear Carol & John:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on January 12, 2023 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 December 14, 2020, Project No. 20-7-670.
At the time of our visit to the site, the foundation excavation had been cut in two main levels
from 5 to 10 feet below the adjacent ground surface. The soils exposed in the bottom of the
excavation consisted of stiff sandy silty clay. Results of swell-consolidation testing performed
on three samples taken from the site, shown on Figures 1 and 2, indicate the soils have low to
moderate compressibility under conditions of loading and wetting. One of the samples showed a
low expansion potential when wetted. No free water was encountered in the excavation and the
soils were moist. We understand that the foundations were designed for the recommended
allowable soil bearing pressure of 3,000 psf.
The soil conditions exposed in the excavation are less expansive than the previous testing
on shallower samples from pits excavated at the site. The deeper clay soils exposed in the
excavation appear suitable for support of spread footings designed for the recommended
allowable bearing pressure of 3,000 psf without structural fill as bearing soil. Loose and
disturbed soils should be removed in the footing areas to expose the undisturbed natural soils.
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 limited 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
Kumar & Associates
Kumar & Associates