9VAC5-40-5822. Operational standards for collection and control systems.
A. Each owner of an MSW landfill with a gas collection and control system used to comply with the provisions of 9VAC5-40-5820 C 2 b shall comply with the following requirements:
1. Operate the collection system such that gas is collected from each area, cell, or group of cells in the MSW landfill in which solid waste has been in place for:
a. Five years or more if active; or
b. Two years or more if closed or at final grade.
2. Operate the collection system with negative pressure at each wellhead except under the following conditions:
a. A fire or increased well temperature. The owner shall record instances when positive pressure occurs in efforts to avoid a fire. These records shall be submitted with the annual reports as provided in 9VAC5-40-5880 H 1;
b. Use of a geomembrane or synthetic cover. The owner shall develop acceptable pressure limits in the design plan; and
c. A decommissioned well. A well may experience a static positive pressure after shut down to accommodate for declining flows. All design changes shall be approved by the board.
3. Operate each interior wellhead in the collection system with a landfill gas temperature less than 55 degrees Celsius and with either a nitrogen level less than 20% or an oxygen level less than 5.0%. The owner may establish a higher operating temperature, nitrogen, or oxygen value at a particular well. A higher operating value demonstration shall show supporting data that the elevated parameter does not cause fires or significantly inhibit anaerobic decomposition by killing methanogens.
a. The nitrogen level shall be determined using Reference Method 3C in Appendix A of 40 CFR Part 60, unless an alternative method is established as allowed by 9VAC5-40-5820 C 2 a.
b. Unless an alternative method is established as allowed by 9VAC5-40-5820 C 2 a, the oxygen shall be determined by an oxygen meter using Reference Method 3A in Appendix A of 40 CFR Part 60 except that:
(1) The span shall be set so that the regulatory limit is between 20 and 50% of the span;
(2) A data recorder is not required;
(3) Only two calibration gases are required, a zero and span, and ambient air may be used as the span;
(4) A calibration error check is not required; and
(5) The allowable sample bias, zero drift, and calibration drift are ±10%.
4. Operate the collection system so that the methane concentration is less than 500 parts per million above background at the surface of the landfill. To determine if this level is exceeded, the owner shall conduct surface testing around the perimeter of the collection area and along a pattern that traverses the landfill at 30-meter intervals and where visual observations indicate elevated concentrations of landfill gas, such as distressed vegetation and cracks or seeps in the cover. The owner may establish an alternative traversing pattern that ensures equivalent coverage. A surface monitoring design plan shall be developed that includes a topographical map with the monitoring route and the rationale for any site-specific deviations from the 30-meter intervals. Areas with steep slopes or other dangerous areas may be excluded from the surface testing.
5. Operate the system such that all collected gases are vented to a control system designed and operated in compliance with 9VAC5-40-5820 C 2 c. In the event the collection or control system is inoperable, the gas mover system shall be shut down and all valves in the collection and control system contributing to venting of the gas to the atmosphere shall be closed within one hour.
6. Operate the control or treatment system at all times when the collected gas is routed to the system.
B. If monitoring demonstrates that the operational requirement in subdivision A 2, 3 or 4 of this section are not met, corrective action shall be taken as specified in 9VAC5-40-5850 C 3 through 5 or 9VAC5-40-5850 E. If corrective actions are taken as specified in 9VAC5-40-5850, the monitored exceedance is not a violation of the operational requirements in this section.
Statutory Authority
§ 10.1-1308 of the Code of Virginia; §§ 110, 111, 123, 129, 171, 172, and 182 of the Clean Air Act; 40 CFR Parts 51 and 60.
Historical Notes
Derived from Virginia Register Volume 15, Issue 12, eff. April 1, 1999; amended, Virginia Register Volume 20, Issue 8, eff. January 29, 2004.