9VAC25-91-180: Groundwater characterization study (GCS)
Where this section sits in the code
- Title 9. Environment
- Agency 25. State Water Control Board
- Chapter 91. Facility and Aboveground Storage Tank (AST) Regulation
- Part V. Groundwater Characterization Study (GCS) and GCS Well Monitoring Requirements
A. Section 62.1-44.34:15 of the Code of Virginia requires the operator to apply to the department for approval of an ODCP. The ODCP shall be accompanied by other relevant information required by the department (e.g., groundwater characterization study (GCS) of each facility with an aggregate aboveground storage capacity of one million gallons or greater of oil). The purpose of this GCS is to determine baseline conditions and flow of groundwater within the geographic boundaries of the facility. The operator's results of the GCS shall be subject to the review and approval of the department and shall be submitted to the department as part of the Oil Discharge Contingency Plan (ODCP) referenced in Part IV (9VAC25-91-170, Oil Discharge Contingency Plan (ODCP) Requirements) of this chapter. The GCS wells are required by 9VAC25-91-170 A 13 a in the ODCP requirements.
B. Section 62.1-44.34:15.1 of the Code of Virginia requires that the operator of a facility with an aggregate capacity of one million gallons or greater of oil conduct monthly gauging and inspection, monitoring of well headspace, and quarterly sampling and laboratory analysis of all groundwater monitoring wells located at the facility to determine the presence of petroleum or petroleum byproduct contamination.
C. Although GCS monitoring wells may be approved for use as part of a leak detection system, the GCS well monitoring requirement should not be confused with any requirement for leak detection monitoring wells required by 9VAC25-91-170 A 18.
Collected 2026-09-14T04:49:10Z. Source file · JSON