HomeMy WebLinkAboutObservation of Excavation 02.23.20221(+AGeotechnigl and Materials 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
February 23, 2022
Chela Murillo
P.O. Box 885
Silt, Colorado 81652
cmurillo2353 @gmail.com
Project No. 21-7-306
Subject: Observation of Excavation, Proposed Residence. 152 Rusty Spur Trail, North of
Cindy's Way, Garfield County, Northwest of Silt, Colorado
Dear Chela:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on February 17, 2022 to evaluate the 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 May 4, 2021, Project No. 21-7-306.
The proposed residence will be a one-story wood frame structure over a walkout basement.
Due to the potential expansion of the claystone at this site, we recommend that footings be
designed for a minimum dead load of 1,000 psf and be placed on 3 feet of structural fill
consisting of 3/-inch road base.
At the time of our visit to the site, the foundation excavation had been cut in two levels from
6 to 10 feet below the adjacent ground surface. The materials exposed in the bottom of the
excavation consisted of claystone bedrock. No free water was encountered in the excavation.
The conditions exposed in the excavation are consistent with those previously encountered on
the site and are suitable for support of spread footings designed for the recommended allowable
bearing pressure of 4,000 with a minimum dead load of 1,000 psf. The road base fill materials
should be protected from frost as they are placed and compacted. We will perform compaction
testing on the structural fill. Concrete should not be placed on frozen subgrade. 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 materials
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 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.
Chela Murillo
February 23, 2002
Page 2
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates, Inc.
Danic
DEH/
Kumar & Associates, Inc. Project No. 21-7-306