Okla. Admin. Code § 165:26-3-171

Current through Vol. 42, No. 4, November 1, 2024

Section 165:26-3-171 - Release investigation and confirmation

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

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

(1)System test. Owners and/or operators must conduct tightness tests that determine whether a leak exists in the storage tank system.

(A) Owners and/or operators must repair, remove or replace the aboveground storage tank system and begin investigation in accordance with (b)(2) of this Section if the test results for the system, tank, or delivery piping indicate that a leak exists.

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

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

(2)Site check. Owners and/or operators must measure for the presence of a release where regulated substances are most likely to be present at the aboveground 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 5 feet (5') from the outside of the AST 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 performed by a PSTD Licensed Environmental Consultant.

(A) If the test results for soil and/or groundwater taken outside the excavation zone or the aboveground 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 aboveground 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 mg/kg in soil may 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 PSTD, after which corrective action may be required under the provisions of Chapter 29 of Commission rules.

Okla. Admin. Code § 165:26-3-171

Added at 21 Ok Reg 2079, eff 7-1-04; Amended at 25 Ok Reg 2187, eff 7-11-08

Amended by Oklahoma Register, Volume 31, Issue 24, September 2, 2014, eff. 9/12/2014

Amended by Oklahoma Register, Volume 32, Issue 23, August 17, 2015, eff. 8/27/2015

Amended by Oklahoma Register, Volume 35, Issue 24, September 4, 2018, eff. 10/1/2018

Amended by Oklahoma Register, Volume 39, Issue 24, September 1, 2022, eff. 10/1/2022