22047_University Place Mall_RA-732_5371_RP_1990-3

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September 19, 1990
Mr. Tom Will
Raleigh Regional Office
State of North Carolina
Department of the Environment,
and Natural Resources
3800 Barrett Drive, Suite 101
Raleigh, NC 27609
Re: Texaco Facility
Hwy 15-501
Chapel Hill, NC
Dear Mr. Will:
3800 Pickett Road
1(7 0 3) 4 �f%VJ031
Health,
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per our conversation of September 18, 1990, please find
attached the Environmental Site Assessment for the referenced
facility. The following recommendations are offered:
1. Install a monitor well in Estes Drive_ In
discussions with North Carolina D.O.T., we were told
that "chances are slim" that we will be successful in
getting approval for encroachment. This location is
the only viable location. We cannot drill in the
right of way adjacent to the station due to the
presence of utilities; and installing a well across
Estes Drive is not recommended because it will be too
remote from the site.
2. Install a monitor well on the adjacent property to
delineate the extent of the hydrocarbons (we will
pursue).
3. Do not install a vertical delineation well. Based on
local knowledge and experience, no aquifer will be
encountered',in the bedrock (wells have been drilled
to approximately 40 feet below ground surface without
water being penetrated). We do not believe that
installing a well to the top of bedrock with well
screen at the base of the well will aid in our
interpretation of the conditions at the site.

State of North Carolina
Department of Environment, Health, and Natural Resources
Raleigh Regional Office
James G. Martin, Govemor William W. Cobey, Jr., secretary
DIVISION OF ENVIRONMENTAL MANAGEMENT
September 26, 1990
Ms. Melissa G.'Richey
Field Environmental Specialist
Star Enterprise
3800 Pickett Road
Fairfax, Virginia 22031
Re: Texaco Facility
Hwy 15--501
Chapel Hill., NC
Dear Ms. Richey:
This office has reviewed your submitted Environmental Site
Assessment with recommendations letter for the above
referenced facility and has developed the following
comments:
1. In reference to recommendation 1 in your letter it
should be noted that Star Enterprise is required to
define the extent of groundwater contamination offsite
to the limits prescribed in the North Carolina
Groundwater Quality Standards located at NCAC Title 15
Subchapter 2L .0202. Because the area across Estes
Drive has been calculated to be hydraulically
downgradient of the contamainant source a well located
in this area would be useful in defining the horizontal
extent of groundwater contamination. Therefore, this
office is requesting that a well be installed in order
to characterize the subsurface conditions. Star
Enterprise should supply this office with a proposed
well location prior to its installation.
2. In reference to recommendation 2 in your letter Star
Enterprise must supply this office with a location for
this proposed well prior to its installation. Upon
installation all new and existing wells must be sampled
within a.24 hour time period and analyzed by EPA method
602.
3800 Barrett Drive, Suite 101 • Raleigh, N.C. 27609
Telephone [phone] • FAX Number [phone]
An Equal Opportunity Affirmative Action Employer

3. In reference to recommendation 3 in your letter this
office will require more information on the
stratigraphy of the site prior to determining whether
the installation of.a well(s) will be required in order
to define the vertical extent of groundwater
contamination. Specifically, Star Enterprise must
clarify the geologic cross --sections submitted as part
of the Environmental Site Assessment Report. Borings
labeled MW5, MW6, and MW8 in Figure 4 and MW5 and MW7
in Figure 5 are not identified by corresponding boring
numbers on Figure 3. In addition, the drill logs shown
in Appendix 1 indicate low blow counts at depths
greater than 20 feet and auger refusal at depths of 22
to 23 feet. Star Enterprise must identify the material
which occurs at a depth of 22 to 23 feet and prove that
it can act as a confining layer between the unconfined
surficial aquifer and a lower confined aquifer.
4. Star Enterprise must supply this office with copies of
well construction logs for all wells completed to date
and also any wells installed for future
assessment/cleanup activities.
S. Star Enterprise must construct a Total VOC
Isoconcentration Map which will be based on the
sampling.event requested in comment 2 above. This map
should include all wells on site in order to get a
"snapshot" of the contaminant plume.
Star Enterprise has until November 30, 1990 to complete the
activities described above and submit the results to this
office. If you have any questions concerning the above
please contact me at [phone].
Sincerely,
Thomas R. Will
Hydrogeologist
Groundwater Section
Raleigh Regional Office

r
15-501/p. 2
4. on July 20, 1990, MW--8 had 0.22 feet of Product on
the water table. We will gage and bail weekly.
I look forward to discussing this site with you at your
convenience.
Sincerely,
STAR ENTERPRISE
14
Melissa G. Richey
Field Environmental Specialist
cc: D. Amari - GTI
K. D. Lattimer - STAR, Atlanta GA
R. G. Larson - TRMI, Houston TX
Attachment