Following its residual risk and technology reviews (RTRs) of the National Emission Standards for Hazardous Air Pollutants (NESHAP) governing off-site waste and recovery operations (OSWRO), the EPA is proposing changes to requirements affecting leak detection and repair (LDAR) and emissions from tanks.  There are about 50 facilities in the regulated OSWRO sector.  The Agency estimates the total nationwide capital costs for the proposed standards at $3.7 million and the total nationwide annualized costs at $800,000.

RTRs

The Clean Air Act (CAA) directs the EPA to conduct RTRs of NESHAPs no more than 8 years after they are promulgated.  The EPA must amend regulations that do not protect the public from HAPs with an ample margin of safety or if additional control technologies can be imposed at a reasonable cost and considering such other factors as technical feasibility and energy impacts.

The OSWRO NESHAP was promulgated in 1996 and amended in 1999.  The EPA is proposing to find that the existing NESHAP is sufficiently protective of public health.  The proposed technology changes are applicable and cost effective for this source category, says the Agency, based on its experience with similar emissions sources emitting similar HAPs at other chemical-type facilities.

Affected sources

In general, the NESHAP applies to waste management units and recovery operations that are located at major sources of HAP emissions and used to manage, convey, or handle used oil, used solvent, or waste received from other facilities and that contain at least one of 97 organic HAPs specified in the rule.

The HAP emissions sources at facilities subject to the OSWRO NESHAP are tanks, containers, surface impoundments, oil-water separators, organic-water separators, process vents, and transfer systems used to manage off-site material and equipment leaks. The NESHAP regulates these emissions sources through emissions limits, equipment standards, and work practices.

Proposed amendments

The proposal includes the following amendments:

• Tanks.  Tanks at existing affected sources with capacities greater than or equal to 75 cubic meters (m3), but less than 151 m3, and a vapor pressure of 13.1 kilopascal (kPa) or greater must comply with Level 2 control.  Level 2 control essentially requires one of five options: a fixed roof tank equipped with an internal floating roof; a fixed roof tank equipped with an external floating roof; a tank with a vapor-tight cover and vented through a closed-vent system to a control device that has an efficiency of 95 percent or more; a pressure tank; or a tank inside a permanent total enclosure (PTE) that is vented through a closed-vent system to an enclosed combustion control device. For tanks at new affected sources, the current OSWRO applicability thresholds are consistent with those required for the chemical industry under other NESHAPs, so no revised applicability requirements were evaluated for tanks located at new sources.

• LDAR.  The LDAR provisions generally require that equipment be monitored for leaks according to a specific schedule and that repairs of detected leaks be completed within a specified number of days.  The proposal would require existing and new OSWRO sources to meet more stringent monitoring requirements for pump seals, valves, and connectors. 

The EPA estimates that the proposed actions will reduce HAP emissions by 211 tons per year.