HomeMy WebLinkAboutObservation of Excavation 01.22.2025
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 22, 2025
Brian and Michelle Klein
309 County Road 263
New Castle, Colorado 81647
Ccrower4@gmail.com
Project No. 18-7-202.A
Subject: Observation of Excavation, Proposed Shop Building, Lot 1, Block 1, Canyon
Creek Properties, 309 County Road 263, Garfield County, Colorado
Dear Brian and Michelle:
As requested, a representative of Kumar & Associates observed the excavation at the subject
site on April 4, 2024 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 H-P/Kumar (now Kumar & Associates) agreement for geotechnical engineering services to
you dated March 15, 2018.
We previously conducted a subsoil study for design of foundations at the site and presented our
findings in a report dated May 4, 2018, Project No. 18-7-202. The proposed construction is
generally similar to that discussed in our previous report. Our previous report recommended the
shop building be founded on spread footings designed for an allowable soil bearing pressure of
1,500 psf with some risk of settlement.
At the time of our site visit, the foundation excavation for the shop building was at two levels
with minor cuts and several feet of fill placed. The perimeter footing areas were about 1 to
1½ feet below the interior floor slab grade. Up to about 2 feet of imported slightly clayey sandy
silt fill had been placed compacted below the footing areas on the natural generally medium
dense, silty sand at the site. Results of swell-consolidation testing performed on a sample taken
from the site, shown on Figure 1, indicate the fill soils are moderately compressible under
conditions of loading and wetting. The sample may have been partly disturbed due to the
relatively high moisture content and sampling process. No free water was encountered in the
excavation and the fill soils were moist to very moist in areas
Compaction testing on the in-place below footing fill was subsequently performed with the
compaction tested to be a minimum 98% standard Proctor density, as typically recommended
for below footing fill. The compaction test results are being provided under separate cover.
The natural soil conditions exposed in the excavation are consistent with those previously
encountered on the site and the structural fill adequately compacted, and suitable for support of
spread footings designed for the recommended allowable bearing pressure of 1,500 psf. The risk
Kumar & Associates