Implications of EPA’s proposed Boiler MACT rules
By Gale Lea Rubrecht
T
he U.S. Environmental Protection Agency (EPA) has
proposed new national emission standards for hazardous air pollutants (HAPs) for industrial, commercial,
and institutional boilers and process heaters, known as the
Boiler MACT (Maximum Achievable Control Technology),
with separate standards applicable to boilers located at either
major or area sources. 75 Fed. Reg. 32,006 and 31,896
(June 4, 2010). EPA is obligated to finalize the rules by
Dec. 16, 2010. If EPA meets this deadline, then existing
sources must achieve the standards by late 2013 or early
2014, and new units must achieve the standards upon the
later of startup or publication of the final rules in the Federal
Register. Although the standards are not yet final, owners/
operators of boilers and process heaters should evaluate
whether their affected units can meet the proposed standards
and, if not, their compliance options. Facilities contemplating purchasing a new boiler or process heater should include
the standards in their decision-making process. This article
highlights some of the features of EPA’s proposals that owners/operators of boilers and process heaters should consider.
Because boilers are found throughout industry, commercial establishments, and institutions, the proposals would
impact numerous sectors of the economy, including chemical
and manufacturing plants, oil and gas extractors, pulp and
paper mills, petroleum refineries, steel works, shopping malls,
hospitals, and universities. However, the proposed standards
generally do not apply to power plants. EPA is developing
a separate MACT standard for power plants that EPA is
required to propose and finalize in 2011.
The major source Boiler MACT would apply to any
new or existing boiler or process heater located at a major
source, with certain exceptions (e.g., a unit subject to another
MACT standard or a unit that combusts “solid waste”). A
“major source” facility emits or has the potential to emit,
considering controls, 10 tons per year of any individual HAP
or 25 tons per year of any combination of HAPs. The minor
source Boiler MACT, which includes “Generally Available
Control Technology” (GACT) as well as MACT standards,
would apply to any new or existing boiler located at a HAPemitting area source (i.e., nonmajor source) with similar
exceptions and also an exception for natural-gas-fired boilers.
As mentioned above, the proposals would not apply
to sources that combust “solid waste.” On the same day
that EPA released the proposed Boiler MACT rules under
Section 112 of the Clean Air Act (CAA), EPA issued a proposal to define nonhazardous secondary materials that are
solid waste. 75 Fed. Reg. 31,844 (June 4, 2010). Whole tires
and coal refuse from legacy coal piles are examples of materials EPA is proposing be considered solid waste when burned
in a combustion unit. Units combusting solid waste are
considered incinerators subject to regulation under Section
129 of the CAA and not boilers. Under a separate, fourth
rulemaking, EPA proposed revisions to the rules regulating
HAP emissions from commercial and industrial solid waste
incineration (CISWI) units incorporating EPA’s proposed
definition of solid waste. 75 Fed. Reg. 31,938 (June 4, 2010).
Depending upon the final definition of solid waste adopted
for combustion units, some units that might otherwise fall
under the boiler source category may be classified as CISWI
units and subject to those standards instead.
Under the MACT, EPA is proposing to establish numerical emission limits, a work practice standard, and a one-time
energy assessment to identify any cost-effective energy
conservation measures. Based upon unit status (i.e., new or
existing), unit design, and fuel type, EPA is proposing eleven
subcategories under the major source Boiler MACT and
three subcategories under the minor source Boiler MACT
rule. For most existing major source boilers and process
heaters having a design heat input capacity equal to or greater than 10 million British thermal units per hour (mmBtu/hr),
EPA is proposing numerical emission limits for: mercury;
dioxin/furan; particulate matter (PM), as a surrogate for
nonmercury metals; hydrogen chloride (HCl), as a surrogate
for acid gases; and carbon monoxide (CO), as a surrogate
for nondioxin and organic HAPs. The area source proposal
would establish limits for only mercury, PM, and CO.
The limits for new units are more stringent than the limits
for existing units, and the limits for both new and existing
units are more stringent than the limits in the September
2004 Boiler MACT vacated by the D.C. Circuit in 2007. EPA
is not establishing separate emission standards for periods of
start-up, shutdown, and malfunction. The same emission limits would apply at all times. Risk-based standards, known as
health-based compliance alternatives, that were included in
the vacated rule are not an option under the 2010 proposal.
Many coal- and biomass-fired units may be unable to meet
the new stringent limits. Owners/operators may, therefore,
need to consider options such as permit limits on HAPs to
avoid being a major source, installing controls, switching fuel
type, and even shutting down.
Averaging emissions, however, is an alternative compliance
approach that EPA supports. Emissions averaging would
be limited to PM, HCl, and mercury and could only be used
for emissions of the same types of pollutants among existing boilers and process heaters in the same subcategory at a
single affected source. Because the emission reductions from
averaging must be equivalent to or greater than the reductions
from controlling emission points to the numerical limits in the
absence of averaging, EPA is proposing to cap the emissions
from each of the sources in the averaging group at the emission level being achieved on the effective date of the final rule.
Additionally, EPA is also proposing to apply a 10 percent
discount factor to emission averaging, which limits averaged
emissions to 90 percent of the numerical emission limits.
For all units that burn gas and for small, existing boilers
and process heaters that burn a fuel other than gas, EPA
is proposing a work practice standard that would require
implementation of a tune-up program. Tune-ups would be
required annually for natural-gas- and refinery gas-fired
units equal to or greater than 10 mmBtu/hr and biennially
for all other affected units. The tune-up would involve
inspecting the burner, flame pattern, and system controlling
Published in Trends Volume 41 Number 6, July/August 2010. © 2010 by the American Bar Association. Reproduced with permission. All rights reserved. This information or any portion thereof may not
be copied or disseminated in any form or by any means or stored in an electronic database or retrieval system without the express written consent of the American Bar Association.
the air-to-fuel ratio; minimizing emissions of CO per the
manufacturer’s specifications; and measuring the concentration in the effluent stream of CO before and after making any
adjustments. Minimizing and measuring CO emissions are
important because the presence of CO indicates incomplete
combustion and elevated organic HAPs.
Beyond emission limits and work practice standards, EPA
is proposing to require that all existing sources having affected
units perform a one-time energy assessment to identify any
cost-effective energy conservation measures, which would be
defined as any measure that has a payback of energy saving
investments within two years or less without regard to the
impact on HAP reductions. According to EPA, facilities can
reduce fuel/energy use by 10 to 15 percent by using best practices to increase their energy efficiency. Depending upon the
size of the facility, EPA estimates the cost of an energy assessment to range from $2,500 to $55,000.
The energy assessment must be performed by someone
who has successfully completed the Department of Energy’s
Qualified Specialist Program for all systems or a professional
engineer certified as a Certified Energy Manager by the
Association of Energy Engineers, using EPA’s ENERGY
STAR Facility Energy Management Assessment Matrix.
This tool identifies gaps in current energy management
practices and provides steps to close the gaps. It may also
raise issues concerning confidential business information for
owners/operators of process heaters. The energy assessment
includes a visual inspection of the boiler system; the determination of operating characteristics of the facility, energy
system specifications, operating and maintenance procedures,
and unusual operating constraints; identification of major
energy-consuming systems; a review of available architectural and engineering plans, facility operation and maintenance procedures and logs, and fuel usage; a list of major
energy conservation measures; the energy savings potential
of the energy conservation measures identified; and a facility
energy management program. The program must be developed according to ENERGY STAR guidelines. Following
the energy assessment, a report identifying the cost-effective
energy conservation measures must be submitted to the
appropriate authority and detail the ways to improve energy
efficiency, the costs and benefits of specific improvements,
and the time frame for recouping those investments.
Large facilities may select in-house engineers to undertake
training to become a certified energy management specialist.
Small facilities may choose instead to rely upon outside
consultants. Because the current number of certified energy
management specialists is limited, outside consultants as well
as in-house engineers may want to become qualified in order
to meet the expected demand.
For units subject to emission limits, compliance would
be demonstrated by an initial performance test followed
by annual performance tests consisting of stack tests, fuel
analyses, or a combination of both. Stack tests must be
conducted at maximum normal operating load, with a minimum of three separate test runs for each performance test.
Continuous monitoring of parameters based upon the size of
the boiler or process heater, fuel type, and pollution control
device would be required. EPA is proposing, for example,
that continuous emission monitoring systems (CEMS) for
CO and oxygen be installed and operated on units with heat
input capacities of 100 mmBtu/hr or greater as well as PM
CEMS for units with capacities of 250 mmBtu/hr or greater.
The proposed rules also include notification, recordkeeping, and reporting requirements. Initial notifications would
likely be due in April 2013 for existing sources and fifteen days
after startup for new sources. Records of each required boiler
tune-up and records demonstrating compliance with limits and
monitoring requirements would be required. If nonhazardous
secondary materials are burned, records would be required
to demonstrate that the materials were not solid waste. Data
from each performance test would be reported electronically
by entering emissions date into EPA’s WebFIRE database.
The database may prove to be an easily accessible, current
resource of emissions data on which to base emissions factors
traditionally used in developing emissions inventories and
control strategies. It should also reduce the burden of future
data collection efforts.
EPA’s proposals, if finalized, will undoubtedly impose significant burdens and costs upon owners/operators of affected
units. While sources typically conduct tune-ups, EPA’s proposed energy assessment represents a new approach to reducing HAPs. The proposals would require only identification of
energy efficiency measures. Whether EPA’s next step will be
to require implementation of those measures is the question.
Gale Lea Rubrecht is a member of Jackson Kelly PLLC and
can be reached at galelea@jacksonkelly.com.
Published in Trends Volume 41 Number 6, July/August 2010. © 2010 by the American Bar Association. Reproduced with permission. All rights reserved. This information or any portion thereof may not
be copied or disseminated in any form or by any means or stored in an electronic database or retrieval system without the express written consent of the American Bar Association.