MACT FOR BOILERS AND PROCESS HEATERS

A new maximum achievable control technology (MACT) standard (Subpart DDDDD) applicable to all boilers and process heaters at major HAP sources will become effective on November 12, 2004.  Following is a summary of this new regulation that is expected to affect nearly 60,000 existing units.  It should be noted, however, that a majority of the existing units are gas-fired boilers and process heaters, which are subject only to an initial notification requirement.

Applicable Dates

Publication date:           September 13, 2004

Effective date:               November 12, 2004

Initial notice due:           March 12, 2005

Compliance date:          November 12, 2007

Exemptions

The following sources are exempt from Subpart DDDDD provisions, including the initial notification requirement. 

Emission Limits

The standard contains emission limits for particulate matter, hydrogen chloride, mercury, and carbon monoxide.  The emission limits vary depending on the unit’s size category and the type of fuel burned.  Particulate matter is a surrogate for non-mercury metallic HAP emissions.  Hydrogen chloride is a surrogate for inorganic HAPs, and the carbon monoxide limits represent organic HAPs. 

An optional emission limit for “total selected metals” can be used in lieu of the particulate matter limit.  Total selected metals are defined as the sum of arsenic, beryllium, cadmium, chromium, lead, manganese, nickel, and selenium emissions.

Existing large solid fuel-fired facilities can average their emissions over all units to demonstrate compliance, but new units must comply individually.

The standard also includes two risk-based alternatives for demonstrating compliance.  The alternatives apply to HCl and manganese emissions, and both can be demonstrated using look-up tables found in Appendix A of Subpart DDDDD.

Work Practice Standards

Carbon monoxide (CO) monitoring has been instituted as a work practice standard for certain new boilers and process heaters, as follows: 

Performance Testing

Boiler and process heater units subject to an emission limit are required to conduct initial and annual performance tests.  The annual requirement can be reduced to once-per-three-years if the three preceding years of test data demonstrate compliance with all limits.

It should be noted that annual tests are not required for HCl, mercury, and total selected metals if compliance with the emission limits is demonstrated via fuel analysis.  Also, new units burning liquid fuel can avoid testing by submitting a signed statement that no residual oil will be burned.  This statement would be submitted with the notice of compliance statement (NOCS).

Monitoring

Continuous compliance can be determined directly via CEMS, or indirectly with continuous parameter monitoring systems (CPMS).  If using a CPMS, the facility must establish the appropriate operating parameters during the initial and annual performance tests.

Sources that are subject to an emission limit or work practice standard are also required to develop a start-up, shut-down, and malfunction plan (SSMP).

Recordkeeping

In addition to copies of all required reports, notices, test results, and permits, sources are required to keep records of: 

Notices and Reports

For sources that are not exempt from this regulation, an initial notification must be submitted to EPA no later than March 12, 2005 (120 days after the publication date).  Other required notices and reports include: