HomeMy WebLinkAboutObservation of Excavation 07.03.20231f+A &.
Geotectmical 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 Employee OWMd Company www.kumarusa.com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
July 3, 2023
SCIB, LLC
Attn: Luke Gosda
0115 Boomerang Road, Suite 5201B
Aspen, Colorado 81611
Luke. gosda(& sunri seco. com
_ Project No. 21-7-593.A
Subject: Observation of Excavation, Proposed Residence, Lot 281, Ironbridge, 353 Blue
Heron Vista, Garfield County, Colorado
Gentlemen:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on June 21, 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 August 9, 2021, Project No. 21-7-593.
The proposed residence is similar to that described in our previous report and will be a 2-story
structure supported on a structural slab foundation imposing a maximum allowable bearing
pressure of 1,500 psf.
At the time of our visit to the site, the foundation excavation had been cut in 2 levels. The main
slab grade was near the surrounding grade and trenches for the thickened slab sections were
about 1lh feet below the adjacent ground surface. The soils exposed in the bottom of the
excavation mainly consisted of gravelly sandy silt and clay fill. Results of two in -place density
tests of about 110 pcf taken at the cut depth indicate at least 98% compaction. 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 structural slab foundation designed for the recommended
allowable bearing pressure of 1,500 psf. 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.
SCIB, LLC
July 3, 2023
Page 2
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar 1'
Steven L.
SLP/kac
Kumar & Associates, Inc. 0 Project No. 21-7-593.A