Section 740. Variance to location of the groundwater monitoring system

A. The applicant may request a variance to the location for the groundwater monitoring system other than at the disposal unit boundary as required by 9VAC20-81-250 A 3 a if he can demonstrate that the response time is sufficiently long to identify and remediate or otherwise contain groundwater that may become impacted before it reaches the facility boundary. This alternate point of compliance with the groundwater monitoring requirements shall be located within the facility boundary and shall not be located farther downgradient than 500 feet from the disposal unit boundary.

B. The application shall provide information on:

1. The hydrogeologic characteristics of the facility and surrounding land. The information shall include an estimate of the width and depth of a plume that may migrate from the disposal unit.

2. The volume and physical and chemical characteristics of the leachate.

3. The quality, quantity, and direction of groundwater flow. This information shall include a determination whether contaminants from the unit will be detectable at the proposed point of compliance.

4. The proximity and withdrawal rate of the groundwater users. This information shall include the estimate of time of travel to private or public supply wells.

5. The availability of alternate drinking water supplies in the event of a groundwater contamination problem.

6. The existing quality of the groundwater, including other sources of contamination and their cumulative impacts on the ground water and whether groundwater is currently used or reasonably expected to be used for drinking water.

7. Practicable capability of the owner or operator. The information shall include an indication of financial capability of the owner or operator to maintain a longer and more costly corrective action program owing to the longer detection time frame associated with the proposed point of compliance.

C. Based on the information received the director will consider the potential overall effect on public health, welfare, and safety of the proposed point of compliance. Consideration will include:

1. Distance to the facility boundary and to the nearest groundwater user or potentially affected surface water;

2. The response time required to remediate or otherwise contain groundwater that may become impacted and potentially affect downgradient water supplies; and

3. Risk that detection may not be representative of worst case condition of the groundwater.

Historical Notes

Derived from Volume 27, Issue 12, eff. March 16, 2011.

Statutory Authority

§ 10.1-1402 of the Code of Virginia; 42 USC § 6941 et seq.; 40 CFR Part 258.