WA-26502_31701_G_RRA_20201124

NCDEQ UNDERGROUND STORAGE TANK SECTION
RISK, RANK, AND ABATEMENT RATING FORM
Incident Name:Wynne Residence Region:
Incident Number:31701 County:
Date:11/24/2020 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 Motor Fuel UST, and Non-UST Petroleum Releases Only
E.
F.
G.
Noncommercial UST Releases Only (including Noncommercial Farm or Residential Motor Fuel USTs)
H.x see note
I.
J.
2. Intermediate Risk (Commercial UST and Non-UST Releases Only)
A.
B.
x
C.
D.
E.
3. Low Risk
A.
SECTION I. Risk Classification Low
WaRO
Martin
ALW
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.
L 100 D
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;
There exists a serious threat of explosion due to the accumulation of vapors in a confined space, as a result of the
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;
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
UST/200 Rev 2017-05_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 =
Private Supply Wells (each well can only be counted once)
x 200 =
x 75 =
Public or Private Wells below 2L .0202 Standards (each well can only be counted once)
x 100 =
B. Threat to Uncontaminated Drinking Water Supplies
Public Supply Wells (each well can only be counted once)
x 40 =
x 10 =
Private Supply Wells (each well can only be counted once)
1 x 20 =20
x 10 =
x 5 =
C. Proximity of Wells to Permitted USTs (PIB Information Check - No Points)
*
*
Surface Water
10 :
5 :
1. Public or institutional water supply well within 500 ft of commercial or noncommercial motor fuel
UST or non-UST plume edge, or 100 feet of other 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 noncommercial
motor fuel UST or non-UST plume edge, or 100 and 150 feet of other 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
noncommercial motor fuel UST or non-UST plume edge, or 150 ft of othernoncommercial 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 noncommercial
motor fuel 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 noncommercial
motor fuel 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.
1. One or more public water supply wells is located within 500' of a permitted UST.
2. One or more private drinking water supply wells is located within 100' of a permitted UST.
Check after
notifying PIB:
1. 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.
CO
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31701
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
PO
I
N
T
S
=
TO
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A
L
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.
UST/200 Rev 2017-05_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 :10
15 :
B. Proximity of Protected Waters to Permitted USTs (PIB Information Check - No Points)
*
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 :5
4. ENVIRONMENTAL VULNERABILITY ASSESSMENT
A. Existing Groundwater Quality - Worst-Case Monitor or Supply Well (assign only one)
5 :5
20 :
40 :
80 :
B. Predominant Contamination Type
20 :
0 :0
5. CONTAMINANT SOURCE ABATEMENT (from Section III)
A. Rank Contributions from Section III: Source Abatement Assignment (automated)
100 :
50 :50
SECTION II. Release Ranking
31701
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.
1. Abatement letter "A" assigned due to an active UST system present onsite. 100 pts total.
OR
OR
OR
OR
PO
I
N
T
S
:
100
2. Abatement letter "D" assigned due to a contaminated soil source remaining. 50 pts total.
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.
TO
T
A
L
1. Surface water classified as High Quality Water (HQW), Outstanding Resource Water (ORW), WS-I,
WS-II or SA is located within 500' of a permitted UST.
Check after
notifying PIB:
No Risk Data Soil to GW Residential Ind/Comm
UST/200 Rev 2017-05_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
OR
C. Residual Soil Contamination
D
OR
D. Contaminant Sources Abated
SECTION III. Source Abatement Assignment 100 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)
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 release product or contaminants
into the environment. Assign Letter "D". (+50 points added to Rank in Section II.5.)
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.)
L 100 D
31701
UST/200 Rev 2017-05_P Pg 4 of 4