MO-9200_0_CA_SCH_20161117_Site Check

CEDAR ROCK ENVIRONMENTAL, P.C.
107 Pioneer Trail ● Graham, North Carolina 27253
[phone]

November 17, 2016

Mr. Bert Blackburn
1020 Charlesmont Court NE
Lenoir, NC 28645

Reference: Inspection of an underground storage tank (UST) located at 1018 Mocksville
Highway, Statesville, North Carolina; Cedar Rock Project # 218422590

Dear Mr. Blackburn:

Cedar Rock Environmental, P. C. (Cedar Rock) performed a site inspection on November 14, 2016
at the above referenced location. The purpose of the inspection was to determine if the UST
previously used for storing heating oil had leaked causing significant contamination of the
underlying soils. It is our understanding the residence was built in 1935. The UST was likely
installed sometime in the 1940s or 1950s. The UST was reported to have last been used in 2003.

An inactive UST was observed to be located parallel to a centered approximately 8.5 feet off the
western foundation wall and about 30 feet from the southwest corner of the house. Both the fill
and vent pipes were observed to be intact. The depth to the top of the UST is approximately 27.5
inches below land surface (bls). The UST has a length of about 129 inches with a diameter of
approximately 47 inches and a capacity of about 1,000 gallons. The UST was measured to contain
approximately 47 gallons of fluid. White flagging was installed to mark the ends of the UST. No
petroleum vapors were noted in the basement. A pair of copper oil lines were severed at the
foundation wall inside the basement adjacent to the UST location.

Once the orientation of the UST was determined, two soil borings were performed, one beneath
each end of the UST, using a 3.25 inch diameter stainless steel hand auger. The soil boring on the
north end of the UST was advanced to a depth of approximately 7.75 feet bls (about 1.5 feet
beneath the UST). The soil boring on the south end of the UST was advanced to a depth of
approximately 8.4 feet bls (about 2.2 feet beneath the UST). The native soil beneath the UST
consists of a reddish brown silt. The soil beneath the north end of the UST exhibited no petroleum
odor or discoloration. However, the soil beneath the south end of the UST appeared to have a
slight petroleum odor suggesting that some leakage may have occurred from the UST. A soil
sample (CR-1) was collected from the base of the southern soil boring and submitted for laboratory
analysis using EPA Method 3550 for Diesel Range Organics (DRO) Total Petroleum
Hydrocarbons (TPH). The results of the sampling detected DRO TPH at a concentration of 127
parts per million (ppm) which exceeds the Action Limit of 100 ppm. The laboratory report and
chain-of-custody form for the soil sample CR-1 is included as an attachment.

Two water supply wells were observed within 150 feet of the observed soil contamination. The
closest well is approximately 60 feet south southeast of the UST and the further well is about 109
feet south southwest of the UST. For this reason, the subject property would be classified as
“High Risk” by the State. The property would be reclassified to “Low Risk” upon the proper
abandonment of both water supply wells.
Mr. Bert Blackburn
November 17, 2016
Page 2

Based on the results of this investigation, significant contamination of the soils underlying the
former UST location has been confirmed. Current law (NCGS 143-215.85 (a) and (b)) requires
that any significant release of contamination be immediately reported to the North Carolina
Department of Environmental Quality (DEQ), Division of Waste Management, Mooresville
Regional Office (704-663-1699). According to State law, upon reporting the release, the current
property owner where a release is discovered is identified by the State as the “Responsible Party”
for any State required action relating to the UST leakage. Cedar Rock will submit a UST-61
form to satisfy the State’s notification requirement for the release.

Currently, the property cannot be legally conveyed until a Notice of Residual Petroleum (NRP)
is filed with the Iredell County Register of Deeds office pursuant to NCGS 143B- 279.11 (d).
The NRP will contain applicable land use restrictions to minimize the risk of exposure to
existing contamination. The land use restrictions prohibit any disturbance of site soils within a
specified radius of the estimated extent of soil contamination and prohibit the future operation
(excluding the existing wells) or installation of any water supply wells on the property. Once the
NRP has been filed and the DEQ has assigned a “Low Risk” classification to the property, the
DEQ will issue a “Conditional” Notice of No Further Action (NFA) letter to formally close out
the release incident. The “Conditional” provision in the NFA letter will be removed upon
completion of Public Notification requirements. Filing the NRP will not be required if all soil
contamination exceeding applicable standards has been removed.

The State currently will not require any initial abatement or remedial action regarding the release
of heating oil from the UST. However, once the presence of the UST and confirmed contaminated
soil is disclosed to other interested parties as required by State law, buyers, home owner’s
insurance providers, or lenders may require initial abatement and/or remedial actions relating to
the UST prior to making any commitments towards the property. In addition, there exists a
potential for further environmental impact to the property from continued leakage from the UST.
The presence of the soil contamination does not appear to pose any health risk at this time.
However, to minimize the spread of further contamination, we recommend either the removal or
the in-place abandonment of the UST. The removal of the UST and contaminated soil would
impact some of the root system of the adjacent oak tree but should not affect the overall health of
the tree. If all soil contamination exceeding applicable standards is removed, obtaining an NFA
letter will not require the abandonment of the two water supply wells. If required, Cedar Rock can
remove the UST and l5 tons of contaminated soil for a charge of $8,000.00. Tonnage in excess of
l5 tons will be an added charge at the rate of $120.00 per ton.

An alternative and less disruptive option to the removal of the UST would be in-place
abandonment. This would consist of exposing a portion of the UST by hand excavation, cutting
a hole about two feet in diameter on the topside of the UST, removing all tank contents, pressure
wash cleaning of the tank interior, and filling the tank with an excavatable flowable fill cement
slurry. A summary report signed by a licensed geologist would be generated that would include
photographs of each step of the abandonment process. Cedar Rock can provide this service for a
charge of $2,800.00 plus $0.75 per gallon of recovered fluids. Preparing and filing the NRP
and performing the Public Notification requirement will cost an additional $1,250.00. By
choosing the UST abandonment option, you will be required to properly abandon both water
Mr. Bert Blackburn
November 17, 2016
Page 3

supply wells to obtain an NFA letter. You should account for the cost of the well abandonments
when deciding which option (tank removal or abandonment) best serves your purposes.

Attached is an invoice for the site inspection. We appreciate the opportunity to be of service to
you. If you have any questions regarding the content of this report, please call me at 336-376-
0394.

Sincerely,

Robert A. Payne, N.C. Licensed Geologist #0970

Attachment