CF-Cozby Library-CS 940520 (3)May 20, 1994
Mr. Jim Bullock
F & S Partners, Inc
3535 Travis, Suite #201
Dallas, Texas 75204-1497
RE: W.T. Cozby Public Library
Coppell, Texas
Dear Mr. Bullock:
We have reviewed the Maxim Engineers, Inc. letter dated October 5, 1994 that included
supplemental geotechnical recommendations for the above referenced project.
We are in agreement with Maxim Engineers that with the utilization of five (5) feet of
select fill, differential vertical soil movement would be reduced to less than one (1) inch.
However, we are concerned that below grade water levels may have fluctuated since the
original investigation such that when the top five feet of soils are removed, water may
be encountered. This concern is based on the groundwater level observed at six (6) feet
below existing grade at test boring location B-3.
Based on the boring logs test results, and with the utilization of a minimum of thirty-six
(36) inches of select fill (minimum of 12 inches of existing surface clays removed) we
estimate the potential differential vertical movement to be one (1) inch or less. Our
analysis is based on the Potential Vertical Rise (PVR) calculation method developed by
the Texas Highway Department (TEX-124E). With the utilization of a minimum of
thirty-six (36) inches of select fill, the potential for encountering groundwater will be
reduced. We, however, do not know what elevation the groundwater will be encountered
within the entire building pad.
Mr. Jim Bullock
May 20, 1994
Page Two
It has been our experience that subgrade and drain pipes sloped approximately ~,4 inch per
foot will sufficiently drain away accumulated groundwater. We recommend this be
verified prior to placement of select fill and drain pipe gravel.
We trust this information meets your needs. If you have any questions or if we can be
of further service, please feel free to contact us.
Sincerely,
GEE Consultants, Inc.
Richard W. Gee, P.E.
President
} WG/lej
cc: Gary Sieb - City of Coppell
Mike Sherpinskas - Diversified Construction Services, Inc.
Ayres Associates
Robert Williams - Brockette Davis Drake, Inc.