1. A. Surface Methane Concentration Standards. Except as provided in Regulations .05D and F, Regulation .09A of this chapter, and §C of this regulation, beginning January 1, 2024, or upon commencing operation of a newly installed gas collection and control system or modification of an existing gas collection and control system in accordance with Regulation .05A of this chapter, whichever is later, no location on the MSW landfill surface shall equal or exceed either of the following methane concentration limits:

   1. (1) Excluding non-repeatable, momentary readings, a methane concentration limit of 500 ppmv as determined by instantaneous surface emissions monitoring in accordance with Regulation .11F(1) and (2) of this chapter; and
   2. (2) An average methane concentration limit of 25 ppmv as determined by integrated surface emissions monitoring in accordance with Regulation .11F(1) and (3) of this chapter.

2. B. Wellhead Temperature Requirement.

   1. (1) Each interior wellhead of a landfill gas collection and control system shall be operated with a landfill gas temperature of less than 62.8°C (145°F), unless a higher operating temperature is approved in writing by the Department.

   2. (2) The Department shall approve an alternate temperature only where a MSW landfill owner or operator submits to the Department a request which uses supporting data to adequately demonstrate that the higher operating temperature value at a particular well will not:

      1. (a) cause a fire; and
      2. (b) significantly inhibit anaerobic decomposition by killing methanogens.

3. C. Construction Activities. The requirements of §A of this regulation do not apply to the working face of the landfill or to areas of the landfill surface where the landfill cover material has been removed and refuse has been exposed for the following activities:

   1. (1) The purpose of installing, expanding, replacing, or repairing components of the landfill gas, leachate, or gas condensate collection and removal system; or
   2. (2) For law enforcement activities requiring excavation.

Authority: Environment Article, §§1-404, 2-103, 2-301—2-303, 10-102, and 10-103, Annotated Code of Maryland

Effective date: June 12, 2023 (50:11 Md. R. 446)

Regulation .03B amended effective August 5, 2024 (51: 15 Md. R. 711)

Regulation .04B amended effective August 5, 2024 (51: 15 Md. R. 711)

Regulation .05 amended effective August 5, 2024 (51: 15 Md. R. 711)

Regulation .06B amended effective August 5, 2024 (51: 15 Md. R. 711)

Regulation .09 amended effective August 5, 2024 (51: 15 Md. R. 711)

Regulation .10C amended effective August 5, 2024 (51: 15 Md. R. 711)

Regulation .11D, F amended effective August 5, 2024 (51: 15 Md. R. 711)