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March 15,2022
Terry and Heidi Ruonavaara
160 Springridge Drive
Glenwood Springs, Colorado 81601
tþ¡uo-49¡1aa'a(!msn'qpm
project No. 2l-7-6gl
Subject: Observation of Excavation, Proposed Residence, Lot 55, Spring Ridge Reserve,
I-Iiclden Valley Drive, Garfield County, Colorado
Dear Terry and Heidi:
As requested, a representative of Kumar & Associates, Ine. observed the excavation at the
subject site on March 15,2022 to evaluate the subsurface materials 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 October 19,2A21, Pr<rject No. 2l-7-681.
We understand the proposed residence has been designed to be founded on spread footings
bearing on the natural bedrock sized for an allowable bearing pressure of 4,000 psf.
At the time of our visit to the site, the foundation excavation was nearly compiete and had been
cut in essentially one level from 3 to I feet below the adjacent ground surface, The subsurface
materials exposed in the bottom of the excavation consisted of hard siltstone/claystone bedrock
in the majority of the excavation. There was about 6-inches of soil overlying the bedrock in the
western edge of the residence excavation and cleck pad excavation area. It was recommended
that the west side of the excavation be deepened down to the undisturbed natural bedrock (by a
depth of about 6-inches). No fi'ee water was encountered in the excavation and the soils and
bedrock were slightly moist to moist.
The subsurface conditions exposed in the excavation are consistent'uvith those previously
encountered on the site and suitable for support of spread footings designed for the
recommended allowable bearing pressure of 4,000 psf. The soil in the western part of the
excavation, loose and disturbed soils, and broken bedrock should be removed in the footing areas
to expose the undisturbed natural bedrock. The bearing materials should be protected from fi'ost
and concrete should not be placed on frozen soils" Other recommendations presented in our
previous reporl 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 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:
Terry and Heidi Ruonavaara
March 15,2022
Page2
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 neod further assistance, please call our office.
Sincerely,
Kr¡mar & Associaf.es, Ine.
Robert L. Duran, P
Rev. by: DEH
RLD/kac
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Ku¡r¡ar & Associates, lnc.Project No.21-7-681