HomeMy WebLinkAboutObservation of Excavation 09.08.2020lcrtffii*"
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fir Employcc Owncd ComPonY
5020 County Road 154
Glenwood Springs, CO 81601
phone: (970)945-7988
fax: (970) 945-8454
email : kaglenwood@kumarusa.com
www.kumantsa.com
Offrce I¡cations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs' and Sunmit County, Colorado
Septenrber 8,2020
Tom Gosnell
447 North Meadow Drive
Rifle, Colorado 81650
teconstruction@icloud. com
Project No. 20-7-485
Subject:Observation of Excavation, Proposed Shop Building Addition, Lot 18, Sun
Meadow Estates,447 North Meadow Drive, Garfield county, colorado
Tom:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on Au-gust 27,2020 to evaluate the soils exposed for foundation support. The
finãings of our obJervations and recommendations for the foundation design are presented in this
reportl Hepworth-pawlak Geotechnical (now Kumar & Associates) previously conducted a
subsoil study for design of foundations at the site and presented the findings in a report dated
October 31,'2o05,¡o¡-No. 105 363. The current observation was performed in accordance with
our agreement for services with you dated August 26,2020'
The proposed addition will be single story and attached to_the east end of the existing shop
uunáing. Spread footings/thickened slab edge placed o1tle natural soils and sized for an
allowable bèaring pressure of 1,500 psf were assumed for foundation support.
At the time of our visit to the site, the perimeter footing excavation had been cut in one level
&om I to lyzfeet below the adjacent ground surface. The soils exposed in the bottom of the
excavation consisted of natural sandy silt and clay. Results of swell-consolidation testing
performed on a sample taken from the cut depth, shown on Figure l, indicatethe soils have low
compressibility under light loading and low collapse potential (settlement under constant load)
when wetted with high Compressibility under additional loading. The results of the laboratory
testing are summari""d in Table 1. No free water was encountered in the excavation and the
soils were slightly moist.
The soil conditions exposed in the excavation appear consistent with those previously
encountered on the sité and suitable for support of spread footings designed for the
recommended allowable bearing pressure of 1,500 psf with the risk of differential settlement
mainly when the bearing soils are wetted. Loose disturbed soils should be removed in the
footing areas and the exposed soils moistened and compacted. Other recommendations
preserited in the 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 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 va¡iations encountered in the excavation
Tom Gosnell
September 8,2020
Page2
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,
Steven L. P
SLP/kac
Attachments: Figure Test Results
Table I - Summary of Laboratory Test Results
Kumar & Associates, lnc. @ Project No.20.7485