Emissions Standards for Sanitary Landfills

The EPA has recently promulgated regulations governing landfill emissions of non-methane organic compounds (NMOC). These regulations are effective March 12, 1996. The intent of the New Source Performance Standards (NSPS) and Emission Guidelines (EG) is to reduce emission of greenhouse gases (methane) and NMOCs. Applicability in both Rules depends on the NMOC emission rates (tons per year) calculated by the EPA Landfill Emissions Model.

Landfills that exceed the NMOC emissions limit are required to install a landfill gas (LFG) collection system to extract and combust LFG (e.g., in a flare, boiler, or engine generator). Operations, monitoring, record keeping, and reporting for the installed collection system must be in accordance with the requirements of the regulations. Specific provisions of both NSPS and EG were recently summarized in a SWANA press release, excerpts of which are presented below.

  New Source Performance Standards (NSPS)

• Applies to all ßnewß landfills. A new landfill is defined as each municipal solid waste (MSW) landfill that started construction [including reconstruction] or modification, or began initial waste acceptance on or after May 30, 1991.
• Within 30 months after a MSW landfill calculating a non-methane organic compound (NMOC) emission rate >50 megagrams (Mg) per year, the provisions of the rule require installation and start-up of a gas collection and control system at the landfill.

Affected MSW Landfills

Maximum design capacity >2.5 million megagrams (Mg) (approximately 2.75 million tons) or 2.5 million M3 (approximately 3.27 million yd3)
 

Exemptions

MSW landfills with design capacity lower than 2.5 million Mg or annual emissions less than 50 Mg (approximately 55 tons) non-methane organic compounds (NMOC)
 

Disposal Areas Requiring Control

Active areas where the first refuse deposited in the areas has reached an age of (5) years or more or areas closed or at final grade where the first refuse deposited in the area has reached an age of (2) years or more
 

Surface Monitoring

Quarterly monitoring for surface concentrations not to exceed 500 parts per million (ppm) methane
 

Emission Control Requirements

Installing a gas collection system and gas utilization or disposal system that achieves a 98 percent reduction of collected NMOC emissions
 

Implementation Schedule

Capacity and Emission Reports within 90 days of the NSPS effective date, March 12, 1996.

Design Plan within one year of the NMOC Emission Report

Start-Up within 18 months of Design Plan

  Emission Guidelines (EG)

Emission guidelines include all ßexistingß MSW landfills that satisfy two conditions:

• The construction, modification, or reconstruction of the landfill began before the proposal date of May 30, 1991; and
• The landfill received waste on or after November 8, 1987 or has additional capacity which may be filled in the future.

The requirements of the emission guidelines are almost identical to those of the NSPS. The main differences between the EGs and NSPS are as follows:

1. Applicability criteria are for ßexistingß landfills;
2. There is flexibility for a State-implemented emission standard;
3. States need to develop a plan to implement the requirements of an EG; and
4. There are different landfill compliance schedules for a state- implemented emission standard. A state has up to 9 months to address EG requirements within its state plan. The EPA has 6 months to review the plan changes. The EG becomes effective upon EPAßs final action on the plan.
5. The EG implementation schedule is similar to that of the NSPS:
   • Capacity and Emission Reports within 90 days of the EG effective date
   • Design Plan within one year of the NMOC Emission Report
   • Start-Up within 18 months of Design Plan

  Title V Operating Permits

Any facility with a design capacity exceeding 2.5 million Mg must obtain a Title V operating permit, whether or not the 50 Mg per year NMOC threshold is exceeded.

SCS Engineers is an environmental consulting firm with over 25 years of experience in the specialty area of landfill gas, emissions, control, and recovery.

Technical Bulletins are prepared by SCS Engineers to alert clients to potential issues that can affect their businesses. For more information on how SCS Engineers can assist you with NSPS-related services, call Jim Walsh at (513) 421-5353.