HomeMy WebLinkAboutObservation of Excavation 10.21.2022'(+A Kumar ni AteMc.®
Geotechnicall and and Materials
als Engineers 5020 County Road 154
and Environmental Scientists Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
Z� email: kaglenwood@kumarusa.com
An Employee Owned Company www.kumarusa.com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
October 21, 2022
Matthew and Kim Gillen
5906 14th Street N.
Arlington, Virginia 22205
gillenmk(i�email. com
Project No. 21-7-450
Subject: Observation of Excavation, Proposed Residence, Lot 2, Filing 8, Elk Springs,
2131 Elk Springs Drive, Garfield County, Colorado
Dear Matthew and Kim,
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on October 21St, 2022 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 June 240h, 2021, Project No. 21-7-450. The current
observations were performed as additional services to, and in accordance with, our proposal for
geotechnical engineering services with you dated May 10, 2021.
At the time of our visit to the site, the foundation excavation had been cut in 2 levels from about
11 feet to about 5 feet below the adjacent ground surface with depth decreasing toward the south
and west. The footers had been poured, and forms were being installed for walls. At all
foundation levels the excavation exposed dense basalt gravel, cobbles, and boulders in a
calcareous sandy silt 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. Any loose and disturbed soils should be removed in slab areas to
expose the undisturbed natural soils prior to the placement of 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
Matthew and Kim Gillen
October 21, 2022
Page 2
(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, Inc.
David Noteboom, Staff Engineer
Rev -
Dan
DEf
Kumar & Associates, Inc.: Project No. 21-7-450