HomeMy WebLinkAboutObservation of Excavation 09.20.2016Ca'ai Amichaux
From: Lena Fowlkes <Ifowlkes@kumarusa.com>
Sent: Wednesday, September 21, 2016 12:10 PM
To: Craig Amichaux (amisacres@outlook.com)
Subject: Excavation Letter for Ami's Acres (Project #16-7-457)
Attachments: 16-7-457 (09-20-16) ex ob.Signed.pdf
Please see attached letter.
If you have any questions, feel free to call.
Thank you,
Lena Fowlkes
Administrative Assistant
Ifowl kesCa7 ku marusa.com
H -P = KUMAR
5020 County Road 154
Glenwood Springs, CO 81601
(970) 945-7988 - Office
19701 945-8454 - Fax
H-P�INMAR
Geotechnical Engineering I Engineering Geology
Materials Testing 1 Environmental
5020 County Road 154
Glenwood Springs, CO 81601
Phone: (970) 945-7988
Fax: (970) 945-8454
Email: hpkglenwood@kumarusa.com
September 20, 2016
Ami's Acres Campground
Attn: Craig Amichaux
P.O. Box 1239
Glenwood Springs, Colorado 81612
(atnisp_cre,5 eaut.IQok.cgrn)
Subject:
Gentlemen:
Office Locations: Parker, Glenwood Springs, and Silverthome, Colorado
Project No. 16-7-457
Observation of Excavation, Proposed Control Shed, Ami's Acres Campground,
50235 Highway 6, Garfield County, Colorado
As requested, a representative of H-P/Kumar observed the excavation at the subject site on
September 19, 2016 to evaluate the soils exposed for foundation support. The findings of our
observations and recommendations for the foundation design are presented in this report. The
services were performed in accordance with our agreement for professional engineering services
to Ami's Acres Campground, dated September 19, 2016.
The proposed shed is located on a fill bench just above the sewage vaults located along the old
highway in the lower, south side of the property. The foundation will consist of a monolithic
structural slab with 12 -inch turn -down edges on the long sides and designed to impose a
maximum bearing pressure of 1,500 psf.
At the time of our visit to the site, the foundation excavation had been cut in one level with the
turn -down edges up to about 1 foot below the adjacent ground surface. Reinforcement steel and
form boards were in place. The fill soils exposed in the bottom of the excavation consisted of
silty sand and gravel with cobbles. The fill bench visually appeared to range between 2 to 6 feet
deep below the building site and has apparently been there for quite some time. No free water
was encountered in the excavation and the soils were slightly moist.
The soil conditions exposed in the excavation consist of undocumented fill which should provide
adequate support but could have settlement potential in the long term, especially if wetted. The
monolithic structural slab placed on the fill soil and designed for an allowable soil bearing
pressure of 1,500 psf should be reinforced to with stand considerable potential settlement. Fill
placed around the foundation can consist of the on-site soils compacted to at least 90% of
Ami's Acres Campground
September 20, 2016
Page 2
standard Proctor density at a moisture content near optimum. The surface should be graded to
prevent ponding within at least 10 feet of the building. No irrigation should be located within 10
feet of the foundation.
The recommendations submitted in this letter are based on our observation of the soils exposed
within the foundation excavation 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
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.
If you have any questions or need further assistance, please call our office.
Sincerely,
H -P KU MAR
Steven L. Pawlak, P.E.
SLP/ljf
H -P % KUMAR
Project No. 16-7-457