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5020 County Road 154
Glenwood Springs, CO 81601
phone: (970) 945-7988
email: kaglenwood@kumarusa.com
www.kumarusa.com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
July 24, 2025
Modfin Design + Build LLP
Attn: Keith Wittenberg
243 Elk Ridge Drive
Glenwood Springs, Colorado 81601
shaggs09@yahoo.com
Project No. 23-7-445.A
Subject: Observation of Excavation, Proposed Residence, Lot 8, Four Mile Ranch, 408 Red
Cliff Circle, Glenwood Springs, Colorado
Dear Keith:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on July 12, 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.
We previously conducted a subsoil study for design of foundations at the site and presented our
findings in a report dated August 21, 2023, Project No. 23-7-445.
We understand that the proposed residence has been designed to be founded with spread
footings placed on the natural soils and sized for an allowable bearing pressure of 2,000 psf.
At the time of our visit to the site, the foundation excavation had been cut in three levels from 3 to
10 feet below the adjacent ground surface. The soils exposed in the bottom of the excavation
consisted of silty sandy gravel with cobbles and small boulders in the eastern half of the
excavation and sandy silt and clay in the western half of the excavation. Results of swell-
consolidation testing performed on a sample of the sandy silt and clay taken from the site, shown
on Figure 1, indicate the soils are compressible under conditions of loading and wetting and
exhibit a low hydrocompression potential when wetted under a constant light surcharge. 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 with a risk of differential settlement due to the variable bearing
conditions, mainly if the bearing soils were to become wetted. A lower risk of differential
Kumar & Associates