HomeMy WebLinkAboutObservation of ExcavationK Geotechnical and Materials Engineers 5020 County Road 154
and Environmental Scientists Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email: kaglenwood@kumarusa.com
An Employ" Company www.kumarusa.com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
October 4, 2023
Edgar Cuc
1853 County Road 109
Glenwood Springs, Colorado 81601
valenzcuc6gInail.com
Project No. 22-7-350
Subject: Observation of Excavation, Proposed Residence, Lot 60, Filing 7, Elk Springs,
38 Aster Drive, Garfield County, Colorado
Dear Edgar:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on October 2, 2023 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 July 11, 2022, Project No. 22-7-350.
The proposed residence will be a one-story wood -frame structure over a walkout basement level.
The residence has been designed to be supported on spread footings sized for an allowable
bearing pressure of 2,000 psf.
At the time of our visit to the site, the foundation excavation was mostly complete and had been
cut in three levels from 3 to 7 feet below the adjacent ground surface. The soils exposed in the
bottom of the excavation consisted of dense basalt cobbles and boulders in a sandy silt caliche
matrix. 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. Loose disturbed soils should be removed in the footing areas to
expose the undisturbed natural soils. Voids created by the removal of large cobbles or boulders
should be backfilled with compacted structural fill or concrete. 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 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.
Edgar Cuc
October 4, 2023
Page 2
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates, li
James H. Parsons, P.E
Rev. by: DEH
JHP/kac
Kumar & Associates, Inc. 0 Project No. 22-7-350