HomeMy WebLinkAboutObservation of Excavation 07.30.2024Kumar & Associates, Inc.®
'( 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 &rooyee Owywd C mpany www.kumarusa.com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and summit County, Colorado
July 30, 2024
Woodstone, Inc
Attn: Alan Short
263 Lewis Lane
Basalt, Colorado 81621
alan(c)woodstoneinc.net
Project No. 23-7-452.A
Subject: Observation of Excavation, Proposed Garage, 1000 Black Bear Ranch Road,
Garfield County, Colorado
Gentlemen:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on July 29, 2024 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 25, 2023, Project No. 23-7-452. The current observation was
performed in accordance with our agreement for professional engineering services with
Woodstone, Inc dated July 29, 2024.
The proposed garage has been designed to be supported on spread footings sized for an
allowable bearing pressure of 1,500 psf with a risk of post -construction settlement or heave
mainly from wetting of the bearing soils.
At the time of our visit to the site, the foundation excavation had been cut in 2 levels from about
2 to 6 feet below the adjacent ground surface. The soils exposed in the bottom of the excavation
mainly consisted of very stiff, sandy clay. The south side encountered gravel and cobbles in a
clay matrix. A shallow depth of organic soil was observed at the southeast corner with cut depth
of about 2 feet. No free water was encountered in the excavation and the soils were 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 movement. The organic soil and loose
disturbed soils should be removed in the footing areas to expose the undisturbed natural soils.
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 limited 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 the recommendations contained in this letter. Our services
Woodstone, Inc.
July 30, 2024
Page 2
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 & AsE
Steven L. Pa
SLP/kac
Kumar & Associates, Inc. 0 Project No. 23-7-452.A