SECTION 165:25-3-8. Release investigation and confirmation

(a)   This Section applies to the investigation of all reportable releases unless PSTD specifically waives any part of this Section in writing.

(b)   Owners/operators must immediately investigate and confirm all suspected releases of regulated substances requiring reporting under this Chapter within seven (7) days of receipt of notice from PSTD using the following steps or another procedure approved by PSTD:

(1)   System test. Owners/operators must conduct tightness tests and if applicable, secondary containment testing, that will determine whether a leak exists in the storage tank system or a breach of either wall of the secondary containment has occurred.

(A)   Owners/operators must repair, replace or permanently closed as defined in OAC 165:25-2-135, the underground storage tank system and begin investigation in accordance with (b)(2) of this Section if the test results for the system, tank, delivery piping or the interstice indicates that a release exists.

(B)   Further investigation is not required if the test results for the system, tank, delivery piping and interstice do not indicate that a release exists and chemical concentrations of regulated substances detected in soil or water are not the basis for a suspicion of a release.

(C)   Owners/operators must conduct a site check as described in (b)(2) of this Section if the test results for the system, tank, delivery piping and interstice do not indicate that a release exists but indicate concentrations of regulated substances detected in soil or water are above action levels cited in (c).

(2)   Site check. Owners/operators must measure for the presence of a release where released chemicals are most likely to be present at the underground storage tank system site. In selecting sample types, sample locations, sample depths, and measurement methods, owners and/or operators must consider the nature of the stored substance, the type of initial alarm or cause for suspicion, the type of native soil, the depth of groundwater, and other factors appropriate for identifying the presence and source of the release. Sample locations should be approximately five feet (5') from the outside of the UST system in native soil or another location approved by PSTD. Analyses for both BTEX constituents and the appropriate TPH must be obtained in all cases. Site check investigations must be conducted by an OCC licensed Environmental Consultant.

(A)   If the test results for soil and/or groundwater taken outside the excavation zone or the underground storage tank system site confirm that a release has occurred, owners and/or operators must begin corrective action in accordance with Chapter 29 of Commission rules.

(B)   If the test results for the native soil and/or groundwater or the underground storage tank system site do not indicate that a release has occurred, further investigation is not required.

(c)   Laboratory analysis of levels of chemical constituent concentrations that may be required to confirm a case are:

(1)   Benzene

(A)   Native Soils - 0.5 mg/kg

(B)   Groundwater - 0.005 mg/l

(2)   Toluene

(A)   Native Soils - 40.0 mg/kg

(B)   Groundwater - 1.0 mg/l

(3)   Ethyl Benzene

(A)   Native Soils - 15.0 mg/kg

(B)   Groundwater - 0.7 mg/l

(4)   Xylene

(A)   Native Soils - 200.0 mg/kg

(B)   Groundwater - 10.0 mg/l

(5)   TPH

(A)   Native Soils - 50.0 mg/kg

(B)   Groundwater - 2.0 mg/l

(C)   If BTEX concentrations are below action levels, a TPH concentration of 500 ppm or mg/kg in soil shall be required to confirm a case at the discretion of PSTD.

(d)   Within twenty (20) days after the reporting of a release, the owner and/or operator must submit a report to PSTD summarizing the steps taken under (a) through (c) of this Section and any resulting information or data. If a release is confirmed through performance of the steps taken under this Section, then the report must be submitted in accordance with a format established by the PSTD, after which corrective action may be required under the provisions of Chapter 29 of Commission rules. Failure to submit reports in a format established by PSTD within the timeframe required may result in an enforcement action.

[Source: Added at 18 Ok Reg 2378, eff 7-1-01; Amended at 21 Ok Reg 2036, eff 7-1-04; Amended at 22 Ok Reg 1730, eff 7-1-05; Amended at 23 Ok Reg 2261, eff 7-1-06; Amended at 25 Ok Reg 1867, eff 7-1-08; Amended at 31 Ok Reg 1007, eff 9-12-14; Amended at 32 Ok Reg 780, eff 8-27-15; Amended at 34 Ok Reg 935, eff 9-11-17; Amended at 35 Ok Reg 985, eff 10-1-18]