SECTION 165:29-3-79. Tier 2 and Tier 3 ORBCA

(a)   Tier 2: Site-Specific Corrective Action Goals

(1)   Under Tier 2, the owner or operator may be required to perform additional site investigation as determined by PSTD. The Tier 2 analysis is conducted in order to determine Site-Specific Target Levels (SSTLs) and appropriate Points of Compliance (POCs). Tier 2 analysis differs from the Tier 1A analysis in that some of the conservative default parameter assumptions of Tier 1A are replaced with site-specific data and the plume is redefined accordingly.

(2)   Target Risk Limits remain the same.

(3)   A report in compliance with the ORBCA Guidance Document must be submitted to the PSTD in accordance with a schedule and format required by PSTD.

(b)   Tier 3: Enhanced Site-Specific Corrective Action Goals

(1)   Where, in the determination of, PSTD, site or near-site conditions dictate more detailed site assessment, the owner or operator may be required to perform a risk analysis using probabilistic evaluations and sophisticated chemical fate and transport models. The extent of this additional site assessment and risk analysis model must be acceptable to the PSTD and must follow the ORBCA Guidance Document.

(2)   Target Risk Limits remain the same.

(3)   A report in compliance with the ORBCA Guidance Document must be submitted to PSTD in accordance with a schedule and format required by PSTD.

[Source: Added at 17 Ok Reg 2317, eff 6-26-00; Amended at 18 Ok Reg 1085, eff 5-11-01; Amended at 22 Ok Reg 1785, eff 7-1-05; Amended at 35 Ok Reg 1033, eff 10-1-18]