HomeMy WebLinkAboutobservation of excavation Permit #8503Kumar & Associates, Inc.®
K 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
May 10, 2024
RC Schneider Construction
Attn: Bob Schneider
218 East Valley Road
Carbondale, Colorado 81623
bhs.austinschneider(a,,icloud. com
Project No. 23-7-672
Subject: Observation of Excavation, Proposed Residence, Lot 22, Filing 9, Elk Springs,
182 Kingbird Court, Garfield County, Colorado
Dear Bob:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on May 10, 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.
These services are provided as supplemental to our agreement for geotechnical engineering
services to RC Schneider Construction dated November 27, 2023. We previously conducted a
subsoil study for design of foundations at the site and presented our findings in a report dated
December 22, 2023, Project No. 23-7-672.
The proposed residence will be a one-story wood -frame structure over a lower walkout basement
level. The residence has been designed to be supported on spread footings bearing on the natural
soils sized for an allowable bearing pressure of 2,500 psf.
At the time of our visit to the site, the foundation excavation had been cut in two levels from 1 to
10 feet below the adjacent ground surface. The soils exposed in the bottom of the excavation,
below about 1 to 6 inches of imported aggregate base course grading material, consisted of basalt
cobbles and boulders in a calcareous sandy silt matrix. The base course was placed as a leveling
course and compacted. 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 2,500 psf. Any disturbed soils excluding base course should be removed
from the footing areas to expose the undisturbed natural soils. Aggregate base course placed
over the natural soils for grading purposes should be moisture treated and compacted. Any water
seepage into the excavation should be collected and diverted away from the footing areas and
any softened soils and mud removed before concrete placement. 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
RC Schneider Construction
May 10, 2024
Page 2
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.
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar & Associates, Inc.
r
Paul J. Graf, Stal
Reviewed by:
James H. Parson
PJG/kac
Kumar & Associates, Inc. 0 Project No. 23-7-672