HomeMy WebLinkAboutObservation of Excavation 08.17.20221f+AKunw ni AsancllateInc.®
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 Employee Owned Company www.kumarusa.com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
August 17, 2022
AML Construction
Attn: Luis Hernandez
P.O. Box 806
Glenwood Springs, Colorado 81602
amlconstructioninc()hotmail.com
Project No. 22-7-570
Subject: Observation of Excavation, Proposed Carport, 9205 Red Canyon Road, Garfield
County, Colorado
Dear Mr. Hernandez:
As requested, a representative of Kumar & Associates observed the excavations at the subject
site on August 16, 2022 to evaluate the materials exposed for foundation support. The findings
of our observations and recommendations for the foundation support are presented in this report.
The services were performed in accordance with our agreement for professional engineering
services to AML Construction dated August 16, 2022.
The proposed carport is on the west side of the existing garage and will be supported by seven
"Bigfoot" footings which appeared to be about 2'/z feet in diameter. Footings were designed for
an assumed soil bearing pressure of 2,000 psf.
At the time of our visit to the site, the seven footing excavations had been cut about 3'/z feet
below the adjacent ground surface. The soils exposed in the bottom of the excavation consisted
of silty sandy gravel with basalt cobbles. No free water was observed in the excavations and the
soils were slightly moist. The footings were in place.
Considering the conditions exposed in the excavation and the nature of the proposed
construction, spread footings placed on the undisturbed natural soil designed for an allowable
soil bearing pressure of 2,000 psf can be used for support of the proposed carport. Exterior
footings should be provided with adequate soil cover above their bearing elevations for frost
protection. Structural fill placed within floor slab areas can consist of the on-site soils or a
suitable imported material compacted to at least 95% of standard Proctor density at a moisture
content near optimum. Backfill placed around the structure should be compacted and the surface
graded to prevent ponding within at least 10 feet of the carport.
The recommendations submitted in this letter are based on our observation of the soils exposed
within the foundation excavations and do not include subsurface exploration to evaluate the
subsurface conditions within the loaded depth of foundation influence. This study is based on
the assumption that soils beneath the footings have equal or better support than those exposed.
The risk of foundation movement may be greater than indicated in this report because of possible
variations in the subsurface conditions. In order to reveal the nature and extent of variations in
AML Construction
August 17, 2022
Page 2
the subsurface conditions below the excavation, drilling would be required. It is possible the
data obtained by subsurface exploration could change the 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.
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates. I
Daniel E. Hardin, PW. $
DEH/kac
Kumar & Associates, Inc. Project No. 22-7-570