HomeMy WebLinkAboutObservation of ExcavationK Kun�r &Associates, Inc 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 fiTltpl W" Owf*d CoMpony
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
October 17, 2025
Jose Salazar
P.O. Box 91
Rifle, Colorado 81650
valentinbustillos09(cDhotmail.6om Project No. 24-7-543
Subject: Observation of Excavation, Proposed Residence, 239 Village Drive, Rifle,
Colorado
Gentlemen:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on October 6, 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 December 31, 2024, Project No. 24-7-543.
The proposed residence has been designed to be support by spread footings placed on the
natural clay soils and sized for the recommended allowable bearing pressure of 1,500 psf with
a risk of settlement.
At the time of our visit to the site, the foundation excavation 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 very stiff, slightly porous sandy silty clay. Results of laboratory in -place
density testing performed on a sample taken at bearing level were 7.3% moisture and 116 pcf
dry density. 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 can be used for support of spread footings designed for the recommended
allowable bearing pressure of 1,500 psf with a risk of settlement. Loose disturbed soils in the
footing areas should be moistened to near optimum and compacted to at least 95% of standard
Proctor density. Other recommendations presented in our previous report which are applicable,
especially those to keep the bearing soils dry, 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. Our services do not include
determining the presence, prevention or possibility of mold or other biological contaminants
(MOBC) developing in the future. If the client is concerned about MOBC, then a professional
in this special field of practice should be consulted.
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates,
Steven L. Pawlak, P.
SLP/kac
Cc:
Clayton Homes —
(karen.gonzaleza-claytonhomes.com)