WI-1116_11608_G_RRA_20221130

NCDEQ UNDERGROUND STORAGE TANK SECTION
RISK, RANK, AND ABATEMENT RATING FORM
Incident Name:Stanley Oil Company Region:
Incident Number:11608 County:
Date:11/30/2022 Ranked By:
Note: a new ranking form must be completed whenever site conditions may have changed, or at least once every 5 years
SECTION I. Initial Risk Classification (Check all that apply)
1. High Risk
All UST and Non-UST Petroleum Releases
A.
B.
C.
D.
Commercial UST, Noncommercial Farm UST, and Non-UST Petroleum Releases Only
E.
F.
G.
Noncommercial UST Releases Only (including Noncommercial Gasoline or Diesel Farm USTs)
H.
I.
J.
2. Intermediate Risk (Commercial UST and Non-UST Releases Only)
A.
B.
C.
D.
E.x
3. Low Risk
A.
SECTION I. Risk Classification
A water supply well not used for drinking water is located within 250 feet of the source area of a confirmed release; or
The groundwater within 500 feet of the source area of a confirmed release has the potential for future use in that there is
no source of water supply other than the groundwater;
A water supply well, including one used for non-drinking purposes, is located within 150 feet of the source area of a
confirmed release;
The source area of a confirmed release is located within a designated wellhead protection area, per 42 USC 300h-7(e);
The levels of groundwater contamination associated with a confirmed release for any contaminant (except ethylene
dibromide, benzene and the aliphatic and aromatic carbon fraction classes) exceed 50 percent of the solubility of the
contaminant at 25 degrees Celsius or 1,000 times the groundwater quality standard or interim standard established in 15A
NCAC 2L .0202, whichever is lower (these levels have been termed “gross contamination levels”); or
There exists a serious threat of explosion due to the accumulation of vapors in a confined space, as a result of the release;
Unassessed free product has been found within 30 feet of a property boundary with a landowner other than the
responsible party for the release; or
There exists an imminent danger to public health, public safety or the environment, as a result of the release.
Surface water is located within 500 feet of the source area of a confirmed release and the maximum groundwater
contaminant concentration exceeds the applicable surface water quality standard and criteria found in 15A NCAC 2B .0200
by a factor of 10;
In the Coastal Plain Physiographic Province (as designated on a map entitled Geologic Map of North Carolina published by
the Department in 1985), the source area of a confirmed release is located where there is recharge to an unconfined or
semi-confined deeper aquifer which the Department determines is being used or may be used as a source of drinking
water;
Vapors from the discharge or release pose a serious exposure risk through vapor intrusion into inhabited structures; or
An unabated surface exposure of free product remains present at a confirmed release from a noncommercial UST.
A water supply well used for drinking water is located within 1,000 feet of the source area of a confirmed release;
WiRO
Onslow
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SCORE
The levels of groundwater contamination associated with a confirmed release for ethylene dibromide or benzene exceed
1,000 times the federal drinking water standard set out in 40 CFR 141(these levels have also been termed “gross
contamination levels”).
A low risk classification means that the risk posed by a release does not meet any of the high or intermediate risk
criteria or, based on site-specific information received by the Department, the release does not pose a significant risk.
I160D
An existing water supply well, including one used for non-drinking purposes, has been contaminated by any UST release or
any non-UST petroleum release;
I
UST/200 Rev 2016-08_P Pg 1 of 4
Incident #
SECTION II. Risk Classification (Assign points as applicable)
1. EMERGENCY HAZARD ASSESSMENT E - FLAG
Complete form with letter "E" assigned to final rating. Once Emergency is abated, a new rating must be prepared.
2. EXPOSURE ASSESSMENT
Groundwater
A. Impacted Water Supplies
Public Supply Wells (each well can only be counted once)
x 600 =
0
Private Supply Wells (each well can only be counted once)
x 200 =
0
x 75 =
0
Public or Private Wells below 2L .0202 Standards (each well can only be counted once)
x 100 =
0
B. Threat to Uncontaminated Drinking Water Supplies
Public Supply Wells (each well can only be counted once)
v x 40 =
0
x 10 =
0
Private Supply Wells (each well can only be counted once)
x 20 =
0
x 10 =
0
x 5 =
0
x 2 =
0
Surface Water
10 :
5 :
1. Public or institutional water supply well containing substances in concentrations exceeding 15A
NCAC 2L groundwater quality standards. 600 pts ea.
2. Private domestic drinking water supply well containing substances in concentrations exceeding 15A
NCAC 2L groundwater quality standards. 200 pts ea.
3. Private well, not used for drinking, containing contamination in detectable concentrations.
75 pts ea.
4. Public or private drinking water supply containing substances that are below the 15A NCAC 2L
groundwater quality standards. 100 pts ea.COUNT11608
An emergency situation exists if the Department determines that the release poses an imminent danger to public health, public
safety, or the environment. (Flag if true, leave blank if no emergency is apparent.)
x
POINTS=TOTAL1. Violation of Class HQW, ORW, WS-I, WS-II, or SA surface water quality standards as a result of groundwater
discharge. 10 pts total.
2. Free product or sheen discovered on surface waters as a result of groundwater discharge. 5 pts total.
1. Public or institutional water supply well within 500 ft of commercial or farm UST or non-UST plume
edge, or 100 feet of noncommercial UST plume edge; plume edge is within radius of influence of
public well; or threat currently unknown. 40 pts ea.
2. Public or institutional water supply well between 500 and 1000 ft of commercial or farm UST or non-
UST plume edge, or 100 and 150 feet of noncommercial UST plume edge; or threat is reasonably
known. 10 pts ea.
3. Private water supply, including non-drinking well, located within 250 ft of commercial or farm UST
or non-UST plume edge, or 150 ft of noncommercial UST plume edge and wells threatened or threat is
currently unknown. 20 pts ea.
4. Private drinking water supply, located between 251 and 500 ft of commercial or farm UST or non-
UST plume edge and wells are threatened or threat is currently unknown. 10 pts ea.
5. Private drinking water supply, located between 501 and 1000 ft of commercial or farm UST or non-
UST plume edge; or wells located within 1000 ft but threat to wells is reasonably known; or an
alternate water source is available. 5 pts ea.
6. Private non-drinking water supply, located between 251 & 1000 ft of commercial or farm UST or
non-UST plume edge;. 2 pts ea.
UST/200 Rev 2016-08_P Pg 2 of 4
Incident #
Section II.2: Surface Water (cont.)
A. Land Use (Choose soil cleanup level. Apply points only if soil contamination exceeds requirement.)
5 :
10 :
15 :
Air Quality
A. Vapor Phase Exposure
20 :
5 :
3. HYDROGEOLOGY and LITHOLOGY
A. Bedrock
20 :
B. Vertical Contaminant Migration
10 :
10
C. Horizontal Contaminant Migration
5 :
4. ENVIRONMENTAL VULNERABILITY ASSESSMENT
A. Existing Groundwater Quality - Worst-Case Monitor or Supply Well (assign only one)
5 :
20 :
40 :
80 :80
B. Predominant Contamination Type
20 :20
0 :
SECTION II. Release Ranking TOTAL160
1. Maximum soil contaminant concentration exceeds "Soil to Groundwater" but below "Residential" exposure
concentration. 5 pts total.
2. Maximum soil contaminant concentration exceeds "Residential" but below "Industrial Commercial"
exposure concentration. 10 pts total.
3. Maximum soil contaminant concentration exceeds the "Industrial/Commercial" exposure concentration or
no risk-based data is available. 15 pts total.
1. Contaminant vapors detected in inhabitable building(s), but levels are below 20% of the lower explosive limit
and health concern levels. 20 pts total.
2. Contaminant vapors detected in other confined areas (uninhabited buildings, sewer lines, utility vaults, etc.)
but levels are below 20% of the lower explosive limit. 5 pts total.
Contamination is located in, on, or within five (5) feet of bedrock. 20 pts total.
Literature or well logs indicate that no confining layer is present above bedrock or within 20 feet of land
surface. 10 pts total.
Data or observations indicate that no discharge points or aquifer discontinuities exist between the discharge,
release, or known extent of contamination and the nearest down-gradient drinking water supply. 5 pts total.
1. Concentrations at less than 10 times the 2L groundwater standards. 5 pts total.
2. Concentrations between 10 and 100 times the 2L groundwater standards. 20 pts total.
3. Concentrations greater than 100 times the 2L groundwater standards. 40 pts total.
11608
4. Free product is present. 80 pts total.
OR
1. Low boiling-point petroleum productes (gasoline, aviation fuel). 20 pts total.
2. High boiling-point petroleum products (fuel oil, kerosene, diesel fuel, etc). 0 pts.
OR
OR
OR
OR POINTS:No Risk Data Soil to GW Residential Ind/Comm
UST/200 Rev 2016-08_P Pg 3 of 4
Incident #
SECTION III. Source Abatement Assignment (Assign Letter)
1. Abated or Unabated Contaminant Source
A. Emergency Situation
OR
B. Active UST System 100 :A
OR
C. Residual Soil Contamination 50 :D
D
OR
D. Contaminant Sources Abated
SECTION III. Source Abatement Assignment D
SECTION IV. Risk, Rank, and Abatement Score
Total: Risk, Rank, and Abatement Score
(Use Risk letter from Section I, total of all Rank points from Section II, and Abatement letter from Section III. Transfer final score to Page 1)
I160D
11608
0
The UST release has been abated and contaminated soil has been removed or remediated.
Assign Letter "R". (No points added to Rank in Section II.5.)
50
An Emergency condition must be immediately abated. Assign letter "E" (and see Section II.1).
UST Systems remain in operation and continue to discharge into the environment.
Assign Letter "A". (+100 points added to Rank.)
The UST release has been abated, however, contaminated soil continues to relase product or contaminants
into the environment. Assign Letter "D". (+50 points added to Rank in Section II.5.)
UST/200 Rev 2016-08_P Pg 4 of 4