HomeMy WebLinkAboutObservation of Excavation 07.10.2023
5020 County Road 154
Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email: kaglenwood@kumarusa.com
www.kumarusa.com Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
July 10, 2023
Russell Cartwright
542 Meadow Creek Drive
Parachute, Colorado 81635
russecart@gmail.com
Project No. 23-7-400
Subject: Observation of Excavation, Proposed Residence, Lot 9, Block 7, The Reserve at
Battlement Creek Village, 676 Meadow Creek Drive, Garfield County, Colorado
Russell:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on June 30, 2023 to evaluate the soils exposed for foundation support. The findings
of our observations and recommendations for the foundation design are presented in this report.
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 November
30, 2006, Job No. 106 987. The current observation was performed in accordance with our
agreement for professional services with you dated June 29, 2023.
The proposed residence is generally like that described in the previous report and will be a
single-story building above crawlspace with slab-on-grade floor in the garage. Spread footings
placed on the natural soils and sized for an allowable bearing pressure of 1,500 psf were
designed for the foundation support.
At the time of our visit to the site, the foundation excavation had been cut in one level from
about 2 to 3 feet below the adjacent ground surface. The soils exposed in the bottom of the
excavation consisted of sandy silt and clay. Results of swell-consolidation testing performed
on a sample taken from the site, shown on Figure 1, indicate the soils have low compressibility
under light loading and moderate compressibility and collapse potential when wetted and loaded.
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 site and can be used for support of spread footings designed for the
recommended allowable bearing pressure of 1,500 psf with a risk of post-construction
differential settlement mainly from wetting the bearing soils. Loose disturbed soils in the footing
areas should be removed and the exposed soils moistened and compacted prior to forming
footings. Other recommendations presented in the previous report which are applicable,
especially those to keep the bearing soils dry, 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 by
others. Variations in the subsurface conditions below the excavation could increase the risk of
Kumar & Associates