ST0701-CS081110;;; HALFF
November 10, 2008
AVO 25816
Mr. Keith Marvin, P.E.
City of Coppell Engineering Services
255 Parkway Boulevard
Coppell, TX 75019
RE: Southwestern Blvd. Improvement (West of Grapevine Creek)
Dear Mr. Marvin:
On May 28th, 2008, a subsurface utility investigation was conducted by Halff Associates
SUE Group, to locate a 24-inch water line near the bridge at Grapevine Creek along
Southwestern Boulevard. The 24-inch water line was located using a geophysical
process. We connected a transmitter to the water vault on the east side of the bridge.
The transmitter sends a frequency reading to our receiver. Based on the strength of the
reading we can locate the line. As the line is being located we either paint or flag the
location on the ground. When we have completed our investigation, the surveyors tie
the paint marks and flags. This information was then processed with the rest of the
survey data, placed into CADD, and used as the location of the existing 24-inch water
line in our design files. I have attached exhibit E1 to show the location of the flags tied,
and the location of the 24-inch water main used in for the design. The proposed
roadway and bridge location are shown in Exhibit E1.
Sincerely,
HALFF ASSOCIATES
Robert Gossett, E.I.T.
d
Jorge Rodriguez, P.E.
HALFF ASSOCIATES, INC.
1201 NORTH BOWSER ROAD
RICHARDSON, TX 75081-2275
I:\25000s\25816\Admin\Correspondence\Letters\L,tr 2008-11-10 COC.doc
TEL (214) 346-6200 WWW.HALFF.COM
FAX (214) 739-0095