Last August, the U.S. Environmental Protection Agency published new proposed landfill gas rules with the Federal Register, making significant changes to the New Source Performance Standards (NSPS). Final versions of these rules are set to be published in July 2016 and may impact the way air emissions from landfills are being managed.
The original NSPS for landfills were issued about 20 years ago. The EPA is supposed to review the standards every eight years. Now the agency “is focused on maximizing potential greenhouse gas emissions reductions from landfills through this rule,” says Anne Germain, director of waste and recycling technology for the Washington, D.C.-based National Waste and Recycling Association.
Matt Stutz, from Fort Worth, Texas-based Weaver Consultants Group, says the EPA is first redefining what a “new source” or “new landfill” is by definition and then is proposing “standards” or rules for these new sources.
“Based on what has been proposed, the EPA is keeping with most of the current requirements under the current NSPS but with some very noteworthy and some worrisome changes,” he says.
The supplemental NSPS rules affect “new” landfill sites or those landfills that are new or were expanded in capacity after July 17, 2014, according to Patrick Sullivan, senior vice president of SCS Engineers in Sacramento, Calif.
“The major component of both rules is the current 50 Mg/year of non-methane organic compounds (NMOCs) emission threshold, which triggers an installation of a [landfill gas (LFG)] collection and control system (GCCS),” Sullivan says. In the proposed rules, that threshold will be lowered to 34 Mg/year for all landfills except existing, closed sites.
“This appears to be the centerpiece of the EPA’s plan to create additional NMOC and methane reductions from landfills,” Sullivan adds. “ With a lowered NMOC threshold, some landfills, particularly those that have been too small to trigger the installation of a GCCS, will be required to install them while others will have to install them earlier than currently required.”
Germain and Stutz agree, with Stutz commenting that other potentially impactful changes are items related to surface emissions monitoring, removal of the requirement to remediate excesses for oxygen and temperature at wellheads, and an optional Tier 4 method.
“The rule also includes operational flexibilities such as the proposed Tier 4 that utilizes site specific surface emissions monitoring (SEM) for installation of a GCCS; the removal of oxygen, nitrogen and temperature limitations for wellheads; and the use of surface emissions monitoring for intermittent operations of low-producing areas,” Germain says. “While we commented that 34 Mg/year is lower than necessary, we did support the operational flexibilities proposed and stated that without them, this lower limit will be impossible to achieve.”
Sullivan says that while it is clear that the EPA wants to make landfills similar to other sources, which have lost their SSM protections, such a decision fails to recognize the unique nature of landfills as a source.
“While EPA suggests that there may be ways that landfills can limit or avoid violations and enforcement actions for SSM events, this provision creates a presumption of excess NMOC emissions and potential deviations during SSM events,” he says. “The SSM language is likely to be a major issue to be further addressed by industry during the comment period.”
Because most landfills already collect and manage their landfill gas, Germain says the reduced threshold will largely impact smaller facilities that would not have had to install a system or would require new landfills to install systems earlier.
“The major impact that the proposed emissions reduction would have to existing landfills is that it could significantly delay the timeline for removing a system,” she says. “For closed landfills without any revenue, this could have had a major impact, which is why EPA proposed a separate closed subcategory.”
According to Stutz, day-to-day landfill operations will be affected.
“If the wellhead standards for oxygen and temperature are removed as proposed this will significant reduce the amount of paperwork and reporting that is required,” he says. “However with the removal of the SSM provisions, the potential for compliance and enforcement action will greatly increase. Day to day operations will be affected as stated above GCCS will have to be installed soon and as such operating around and replace GCCS components will increase.”
Landfill operators need to be prepared for these new rules to minimize the impact on their operations.
“Each landfill should be reviewing its status against the new rules and determining which rule it will be subject to and when that is likely to take effect as well as assessing how it will comply with any of the new or updated requirements,” says Sullivan. “Sites that are not currently subject to the GCCS requirements of the NSPS/EG because NMOC emissions have been maintained below 50 Mg/year must assess how the new 34 Mg/year threshold will affect them.”
At the same time, Sullivan says operators should evaluate whether the Tier 4 methodology might benefit them, and maybe consider an initial Tier 4 SEM event prior to the rule taking effect to see how they might fare.
“Landfills may also want to do some preliminary SEM of cover penetrations, particularly if they have not done that before, and see what improvements they may need to make to avoid leaks. The landfills should also assess which of the various required reports and plans they may need to revise or create to meet the rule,” he says.
There are a number of potential changes to operational practices that could significantly impact landfill gas operations that operators need to prepare for, according to Germain.
“This includes changes to the wellhead standards and surface emissions monitoring. The current rules are very prescriptive requiring actions that might not make sense for overall system operations,” she says. “For the wellhead standards, EPA has proposed removing the temperature, oxygen and nitrogen standard for individual wellheads. This will greatly simplify landfill gas system operations and is supported by industry. By contrast, EPA is considering increased monitoring of surface emissions. The industry has raised numerous concerns with respect to this.”
Stutz, Sullivan and Germain will discuss this topic further at Waste Expo. The session, “The Impact of the New Source Performance Standards for Landfills,” will take place from 1:30-2:45 p.m. on June 7.