HomeMy WebLinkAboutObservation of Excavation 11.25.2022l(+rf Xumar & Associates, lnc.'
Geotechnical and Materials Engineers
and Environmental Scientists
5020 County Road 154
Glenwood Springs, CO 81601
phone: (970)945-7988
fax: (970) 945-8454
email : kaglenwood@kumarusa.com
tl'wv.kuntarusa.comAn Employee Ownêd Çcrnpcny
Office Locations: Denver (HQ), Parker, Colorado Springs, Fofi Collins, Glenwood Springs, and Summit County, Colorado
November 25,2022
Luis Vargas
792 Castle Valley Boulevard, Apt. A
New Castle, Colorado 81647
umbllc202O@gmail'com projectNo.2l-7-1 26.01
Subject: Observation of Excavation, Proposed Residence,49 Pinyon Place, Lot 15,
Block 9, Monument Creek Village, Battlement Mesa, Colorado
Dear Mr. Vargas:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on November 16,2022 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 February 5,2021, Project No. 21-7-126. The current
observation was performed in accordance with our agreement for professional services with you
dated November 16, 2022.
The proposed residence will be a one-story wood frame structure over a crawlspace with an
attached garage with slab-on-grade floor. Spread footings placed on the natural clay soils were
designed for an allowable soil bearing pressure of 2,000 psf based on our previous report.
At the time of our visit to the site, the foundation excavation had been cut in one level from 1 to
3 feet below the adjacent ground surface. The soils exposed in the bottom of the excavation
consisted of sandy silt. Results of swell-consolidation testing performed on a sample taken from
the site, shown on Figure 1, indicate the soils are moderately collapsible under conditions of
loading and wetting. No free water was encountered in the excavation and the soils were slightly
moist.
The soil conditions exposed in the excavation are similar to those previously encountered on the
site and can be used for support of spread footings designed for the recommended allowable
bearing pressure of 2,000 psf with a risk of settlement. Loose and disturbed soils should be
removed in the footing areas to expose the undisturbed natural soils. The bearing soils should be
protected from frost and concrete should not be placed on frozen soils. Good surface dtainage
away from the foundation walls, as described in our previous report, should be maintained
around the outside of the house. 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 limited subsurface exploration at the site.
Luis Vargas
November 25,2022
Page2
Variations in the subsurface conditions below the excavation could increase the risk of
foundation movement. V/e 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,
K&sæax & åssæcå*f*s,
Daniel E. Hardin,
Rev. by: SLP
DEH/kac
attachment Figure I * Swell-Consolidation Test Results
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21 -7 - 126.01 Kumar & Associates SWILL_CONSOLIDATION TEST RESULTS 1Fig
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