HomeMy WebLinkAboutObservation of ExcavationKumar & Associates, Inca 5020 County Road 154
' Geotechnical and Materials Engineers Glenwood Springs, CO 81601
and Environmental Scientists phone: (970) 945-7988
email: kaglenwood@kumarusa.com
www.kumarusa.com
An Employee Owned Company
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
TF Builders
Attn: Bobby Martin
738.0 Countv Road 100
Carbondale, Colorado 81623
bobby tebuilders, net
Project No. 25-7-723
Subject: Observation of Excavation, Proposed Addition, Lot E-21, Aspen Glen, 63 Buffalo
Lane, Garfield County, Colorado
Gentlemen:
As requested, a representative of Kumar .& Associates, Inc. observed the excavation at the
subject site on December 29, 2025 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 of foundations at the site and presented the findings in a report dated
October 3, 1996, Job No. 196.4.75. The .current observation was performed in accordance with
our agreement for professional services with TE Builders dated December 22, 2025.
The proposed addition will be attached to the east side of the residence and was designed to be
supported on spread footings sized for an assumed allowable bearing pressure of 2,000 psf.
At the time of our visit to the site, the footing trench excavation and 2 separate footing pad
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The soils exposed in the bottom of the excavation consisted of silty sandy clay with gravel and
scattered cobbles. The results of a gradation analysis performed on a sample of the clay
(minus 3-inch fraction) obtained from the site are presented on Figure 1. No free water was
encountered in the excavation and the soils were slightly moist to moist and not frozen.
The soil conditions exposed in the excavation generally appear consistent with those previously
encountered on the site and can be used for support of spread footings designed for the
assumed allowable bearing pressure of 2,000 psf with a risk of settlement due to the fine-
grained type of soil. Loose disturbed soils should be removed in the footing areas to expose the
undisturbed natural soils. The bearin.a 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.
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foundation movement. We should be advised of any variations encountered in the excavation
conditions for possible changes to recommendations contained in this letter. Our services do
not include determining the presence, prevention or possibility of mold or other biological
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DIAMETER OF PARTICLES IN MILLIMETERS
SAND
GRAVEL COBBLES
CLAY TO SILT
FINE MEDIUM 1COARSE1
FINE I COARSE
GRAVEL 17 X
SAND 16 X SILT AND CLAY 67 X
SAMPLE OF: Silty Sandy Clay with Gravel FROM:
Bottom of Footing Excavation
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GRADATION TEST RESULTS Fig. 1
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