RICE MACT Amendments Create New Challenges



On January 30, 2013, the U.S. EPA issued a series of amendments to the National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines (RICE NESHAP). Revisions were also made to the Standards of Performance for Stationary Compression Ignition Internal Combustion Engines (CI RICE) and Standards of Performance for Stationary Spark Ignition Internal Combustion Engines (SI RICE) for consistency with the RICE NESHAP. The amendments for these RICE standards, located in 40 CFR Part 63, Subpart ZZZZ, 40 CFR Part 60, NSPS IIII and 40 CFR Part 60, NSPS JJJJ, became effective on April 1, 2013.

RICE MACT quote

The amendments, which include flexible compliance alternatives, revisions to definitions and emission standards, and several technical corrections, are summarized as follows:

  • New total hydrocarbon (THC) compliance demonstration option is added for 4-stroke rich burn (4SRB) spark ignition (SI) engines greater than 500 brake horsepower (bhp) subject to a 76 percent or more formaldehyde reduction
  • Operational limitations on the use of emergency engines for emergency demand response, during periods of voltage or frequency deviation, and for local grid reliability are finalized
  • The use of emergency engines for peak shaving is addressed
  • Management practices are finalized for 4-stroke SI engines greater than 500 bhp located at area sources of hazardous air pollutants (HAP) in remote areas in lieu of numerical emission limits
  • Clarification is provided that existing certified Tier 3 (Tier 2 engines above 560 kW) compression engines that were installed prior to June 12, 2006 are in compliance with the RICE NESHAP
  • The definition of remote areas of Alaska is expanded beyond the 2010 amendments
  • Standards for existing non-emergency CI RICE greater than 300 bhp on offshore vessels that are area sources of HAP are revisited
  • Several miscellaneous corrections and revisions are made, such as clarifying that a Startup, Shutdown, and Malfunction Plan (SSMP) is not required for a continuous parameter monitoring system (CPMS)
Total Hydrocarbon Compliance Option

EPA has added an alternative compliance option for 4SRB SI engines greater than 500 hp subject to a 76 percent or more formaldehyde reduction. The existing method for demonstrating compliance is to test the engine and demonstrate a 76 percent or greater reduction in formaldehyde emissions. The compliance alternative is to test the engine and demonstrate at least a 30 percent reduction of total hydrocarbon (THC) emissions. The cost difference between testing for formaldehyde and THC is significant. According to a leading stack testing firm, the cost of a single engine test for formaldehyde exceeds the cost for THC by around $2,500-$3,000. However, this cost difference diminishes as the number of engines per test increases due to the significant level of cost tied up in the equipment fee for the formaldehyde testing.

Emergency Demand Response and Local Grid Reliability Provisions

In the 2010 amendments to the RICE NESHAP, which extended the rule applicability to existing stationary RICE, the definition of emergency use provided for emergency demand response participation for up to 15 hours per year (which counted towards the 100 hours per year allowable for maintenance and readiness checks). This definition of emergency use was different from the definition provided in the original RICE NESHAP promulgated in 2004 which covers certain RICE greater than 500 hp at major sources. To further complicate the issue, these NESHAP definitions differed from the emergency use definition in the new source performance standards (NSPS) applicable to stationary RICE (NSPS IIII and NSPS JJJJ). The recent 2013 amendments make these definitions consistent across stationary engine rules. Existing stationary emergency engines greater than 500 HP at major sources of HAPs must now meet this new emergency engine definition to remain exempt from the rule per 63.6590(b)(3)(iii).

The revised definition of emergency use allows for up to 100 hours per year use for any combination of the following: maintenance checks and readiness testing, emergency demand response (as defined in the rule), and periods of voltage of frequency deviations more than 5% below standard. It also allows for up to 50 hours per year non-emergency use (which counts towards the 100 hours total) which may include supplying power as part of a financial arrangement to ensure local grid integrity, provided certain criteria are met.

RICE MACT engineWhile existing commercial, institutional and residential emergency RICE located at area sources are exempt from the RICE NESHAP, the 2013 amendments added provisions which stipulate that such engines cannot operate or be contractually obligated to be available to operate more than 15 hours per calendar year for emergency demand response or to provide local grid reliability and still meet this exemption criteria.

With these amendments, EPA has added a provision requiring existing emergency CI RICE greater than 100 HP and new emergency CI RICE greater than 500 HP that are enrolled in emergency demand response and system reliability programs, as well as existing, non-emergency CI RICE that are 300 HP or greater, to burn ultra-low sulfur diesel fuel (15 ppm sulfur) and record operational hours beginning January 1, 2015. Any existing diesel fuel that was purchased prior to January 1, 2015 may be used until depleted. Owner/operators will be required to report the dates and times the engines operate for emergency demand response to the EPA beginning with operation during the 2015 calendar year.

Peak Shaving

The June 7, 2012 proposed amendments included a temporary provision for existing stationary emergency engines located at area sources to peak shave for up to 50 hours per year through April 2017. This provision of the proposed rule was not finalized. The 2013 amendments include a provision limiting the use of existing stationary emergency engines located at area sources of HAP to 50 hours per year for peak shaving or non-emergency demand response prior to May 3, 2014. This provision specifies that this operation must be part of a load management programs with a local distribution system operator.

Remote Engines

The 2013 amendments establish a new subcategory for existing spark ignition engines located in sparsely populated areas, called remote engines. EPA is creating this category based on the existing Department of Transportation (DOT) classification system for natural gas pipelines. A remote area is defined as either a DOT Class 1 pipeline location or, if the engine is not on a pipeline, a location where there are 5 or fewer buildings intended for human occupancy within a 0.25 mile radius of the facility.

Owners and operators of existing stationary non-emergency 4-stroke lean burn (4SLB) and 4-stroke rich burn (4SRB) RICE > 500 HP at area sources that are located in sparsely populated areas are required to 
perform the following:

  • Change the oil and filter every 2,160 hours of operation or annually, whichever comes first
  • Inspect spark plugs every 2,160 hours of operation or annually, whichever comes first, and replace as necessary
  • Inspect all belts and hoses every 2,160 hours of operation or annually, whichever comes first, and replace as necessary

Owners and operators must evaluate their remote status on an annual basis. If the engine no longer meets the remote criteria, the engine must be in compliance with the emission standards specified for populated areas within one year.

For non-remote 4-stroke engines greater than 500 HP at area sources located in populated (non-remote) areas, EPA is now requiring the installation of a catalyst and associated monitoring to reduce HAP emissions. Owners and operators of 4SLB engines must install an oxidation catalyst and owners and operators of 4SRB engines are required to install NSCR. This removes the 
option in previous versions of the RICE NESHAP for alternative emission control equipment such as an afterburner for CO control.

These sources must conduct an initial compliance test to demonstrate at least a 93 percent reduction in CO emissions or a CO concentration level of 47 ppmvd at 15 percent O2 for a 4SLB engine. A 4SRB engine must demonstrate at least a 75 percent CO reduction, a 30 percent THC reduction, or a CO concentration level of 270 ppmvd at 15 percent O2.

RICE MACT 100 Hours Graphic

Prior to the 2013 amendments, owners and operators of 4-stroke engines greater than 500 HP at area sources were required to install controls, monitor the catalyst inlet temperature, install a CPMS, and have a Site Specific Monitoring Plan for the monitoring system (SSMP). Continuous monitors are costly to maintain and operate and are easy compliance targets based on continuous monitoring requirements (e.g., certification, relative accuracy testing, required uptime, quality assurance, etc.). However, one of the most significant changes included in the 2013 amendments is the option for these facilities to use a high-temperature shutdown device that kills the engine if the catalyst temperature is too high. By using the high-temperature shutoff, the need for a CPMS and SSMP are eliminated. This can result in a substantial reduction of operating costs and reduced compliance liability for a facility. Facilities that do not use the high temperature shutoff will be required to install the CPMS, develop a SSMP, and submit reports in accordance with those provisions.

Lastly, for owners and operators of 4-stroke engines greater than 500 HP at area sources, there are new special provisions for source testing. Emissions in excess of the specified levels in the rule are not considered a violation. Instead, the owner or operator must shut down the engine and take corrective action. A re-test must be completed in 7 days. If the engine still does not meet emission levels, the engine must be shut down again and may not be operated until testing demonstrates that emissions are less than the specified levels in the rule.

Limited Applicability

The 2013 amendments include some changes with more limited applicability, such as broadening the definition of remote area sources in Alaska, allowing extended compliance deadlines for engines that must be upgraded to meet more stringent local or state regulations, and revising standards for existing non-emergency CI RICE greater than 300 bhp on offshore vessels that are area sources of HAPs.

The January 30, 2013 amendments specify that any existing certified Tier 3 (Tier 2 engines above 560 kW) compression engine that was installed prior to June 12, 2006 is in compliance with the RICE NESHAP.

Miscellaneous Corrections and Revisions

Several miscellaneous changes were also addressed in the recent amendments. Among the most notable were the clarification that a Startup, Shutdown, and Malfunction Plan (SSMP) is not required for a continuous parameter monitoring system (CPMS) and the requirement to record the monthly pressure for engines that were added to the rule in 2010 (Existing stationary RICE ≤ 500 HP located at major sources of HAPs and existing SI stationary RICE (all sizes) located at area sources of HAPs) was removed.

Sources with affected RICE should review the final rule and amendments carefully to determine compliance requirements based on the promulgated standards. For assistance in determining applicability and complying with the new standards, contact your local Trinity office at (800) 229-6655.