34010 Federal Register / Vol. 65, No. 102 / Thursday, May 25, 2000 / Rules and Regulations

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 63

[AD–FRL–6706–1]

National Emission Standards for

Hazardous Air Pollutants for Source

Categories

AGENCY: Environmental Protection

Agency (EPA).

ACTION: Interpretative rule.

SUMMARY: This interpretative rule

clarifies the construction by EPA of the

applicability of sections 112(g) and

112(j) of the Clean Air Act (CAA), and

of the regulations implementing these

provisions for stationary combustion

turbines in Subpart B—Requirements

for Control Technology Determinations

for Major Sources in Accordance With

Clean Air Act Sections 112(g) and

112(j).

Specifically, EPA has determined that

case-by-case maximum achievable

control technology (MACT)

determinations under subpart B must be

made for all new or reconstructed major

source stationary combustion turbines,

regardless of whether they are part of a

combined cycle system. Waste heat

recovery units, including duct burners,

which are part of a combined cycle

system are considered to be steam

generating units. New or reconstructed

waste heat recovery units would not be

subject to case-by-case MACT

determinations under subpart B if they

are electric utility steam generating

units.

Elsewhere in today’s Federal Register,

EPA is withdrawing the interpretative

rule as published on April 21, 2000, at

65 FR 21636. This final interpretative

rule supersedes the interpretative rule

erroneously published at 65 FR 21636.

EFFECTIVE DATE: June 26, 2000.

FOR FURTHER INFORMATION CONTACT: For

further information, contact Sims Roy,

Combustion Group, Emission Standards

Division (MD–13), U.S. Environmental

Protection Agency, Research Triangle

Park, North Carolina 27711, telephone

number: (919) 541–5263, facsimile:

(919) 541–5450, electronic mail address:

roy.sims@epa.gov.

SUPPLEMENTARY INFORMATION:

Regulated entities. Stationary

combustion turbines which meet the

criteria for major sources are the

regulated entities addressed by this

interpretative rule.

I. Why Is EPA Issuing This

Interpretative Rule?

The EPA has decided to issue this

interpretative rule to resolve an

ambiguity in the construction of the

exclusion for electric utility steam

generating units set forth in 40 CFR

63.40(c). That provision states, ‘‘The

requirements of [40 CFR part 63, subpart

B] do not apply to electric utility steam

generating units unless and until such

time as these units are added to the

source category list pursuant to section

112(c)(5) of the Act.’’ This applicability

exclusion was intended to limit the

need for case-by-case MACT

determinations for new or reconstructed

sources under CAA section 112(g) and

40 CFR 63.40–63.44, but the same

exclusion would also generally apply to

case-by-case MACT determinations for

new and existing sources pursuant to

CAA section 112(j).

The term ‘‘electric utility steam

generating unit’’ is defined in CAA

section 112(a)(8) and at 40 CFR 63.41,

as follows:

The term ‘‘electric utility steam generating

unit’’ means any fossil fuel fired combustion

unit of more than 25 megawatts that serves

a generator that produces electricity for sale.

A unit that co-generates steam and electricity

and supplies more than one-third of its

potential electric output capacity and more

than 25 megawatts electric output to any

utility power distribution system for sale

shall be considered an electric utility steam

generating unit.

The EPA explained its reasoning for

the electric utility steam generating unit

exclusion in the preamble to the final

rule implementing CAA section 112(g)

for new and reconstructed major sources

(61 FR 68387, December 27, 1996). We

noted that CAA section 112(n)(1)

required us to perform a study of the

hazards to public health associated with

hazardous air pollutants (HAP)

emissions from electric utility steam

generating units. After completing the

required study and considering the

results, we are authorized to regulate

such units under CAA section 112 if we

determine such regulation is

appropriate and necessary. We have not

at this time made a determination

whether such regulation is appropriate

and necessary, but we are required by

court order to make a determination by

December 15, 2000. We excluded

electric utility steam generating units

from case-by-case MACT determinations

under section 112(g) because we

concluded that such determinations

should only be made for sources which

would otherwise be subject to section

112 MACT standards.

Stationary combustion turbines were

included on the list of source categories

issued pursuant to CAA section

112(c)(1), and we are, therefore,

required to issue a MACT standard

applicable to this category pursuant to

CAA section 112(d). Proposal of the

MACT standard for this source category

is anticipated in late 2000, with

promulgation in early 2002.

Stationary combustion turbines may

be used to generate electricity. These

stationary combustion turbines are

sometimes combined with waste heat

recovery units which generate steam by

extracting heat from the exhaust gases

(i.e., combined cycle systems). The fact

that stationary combustion turbines can

be used to generate electricity has

created some ambiguity about whether

combustion turbines used in this

manner are considered electric utilities.

On the one hand, EPA believes that

the most reasonable construction of the

statutory definition of electric utility

steam generating units would not

include any stationary combustion

turbine, regardless of whether it is used

by an electric utility to generate

electricity, and regardless of whether it

is attached to a waste heat recovery unit

which generates steam. Accordingly, we

are developing a MACT standard to

regulate emissions from all stationary

combustion turbines pursuant to CAA

section 112(d).

On the other hand, we also recognize

that the first sentence of the statutory

definition creates ambiguity concerning

whether an electric utility unit must

even generate steam to be included.

This ambiguity has been compounded

by the language in the preamble to the

final section 112(g) rule, which

predicates the exclusion for electric

utilities based on the study performed

pursuant to CAA section 112(n)(1). That

study did, in fact, include some very

limited consideration of stationary

combustion turbines. In light of these

ambiguities, different permitting

authorities have reached differing

conclusions concerning whether a caseby-case MACT determination under

section 112(g) is required for new or

reconstructed major source stationary

combustion turbines. At various times,

offices within EPA have also given

differing interpretations concerning

whether a case-by-case MACT

determination is required for such

facilities.

This interpretative rule is intended to

clearly resolve the ambiguity in the

construction of 40 CFR 63.40(c) as

applied to stationary combustion

turbines. This interpretative rule will

become legally effective and binding on

June 26, 2000. After that date, all EPA

offices and permitting authorities must

adhere to this interpretative rule. Those

EPA offices and permitting authorities

who become aware of this interpretative

rule, or the construction of the statute

set forth herein, prior to the effective

Federal Register / Vol. 65, No. 102 / Thursday, May 25, 2000 / Rules and Regulations 34011

date should adopt this construction to

the full extent it is practicable to do so.

However, EPA will not seek to revisit

the legality of, or to otherwise

reconsider, any final actions previously

taken in good faith based on a

conclusion that stationary combustion

turbines used to generate electricity fall

within the exclusion.

II. What Is the Agency’s Interpretation?

The EPA construes the term ‘‘electric

utility steam generating unit,’’ as

defined by CAA section 112(a)(8) and 40

CFR 63.41, to exclude all stationary

combustion turbines, regardless of

whether or not such turbines are

utilized to generate electricity or

utilized by an electric utility, and

regardless of whether or not such

turbines are utilized in conjunction with

waste heat recovery units (i.e.,

combined cycle systems). Therefore, a

case-by-case MACT determination is

required for each new or reconstructed

stationary combustion turbine which is

a major source.

The phrase ‘‘steam generating unit’’ in

the term ‘‘electric utility steam

generating unit’’ is critical to

interpreting which types of combustion

units are covered by this definition and

which types are not. The definition

clearly covers a conventional fossil fuel

fired steam generating unit (e.g., coalfired boiler) which extracts heat from

the combustion of fuel and generates

steam for use in a steam turbine, which

in turn provides shaft power to spin an

electric generator and generate

electricity.

However, we do not believe this term

was intended to cover a stationary

combustion turbine which extracts shaft

power from the combustion of fuel and

spins an electric generator to generate

electricity. Such a combustion turbine

does not extract heat to generate steam.

In fact, there is no steam generated at all

in a combustion turbine. Hence, we

conclude that the term ‘‘electric utility

steam generating unit’’ does not include

any stationary combustion turbine, and

that such turbines must be regulated

under a section 112(d) MACT standard

or a section 112(j) determination.

Moreover, a case-by-case MACT

determination under section 112(g) is

required for any new or reconstructed

stationary combustion turbine which is

a major source.

This reasoning can be further applied

to combined cycle systems. For

purposes of this discussion, a combined

cycle system is a combination of a

stationary combustion turbine and a

waste heat recovery unit.

In a combined cycle system, a

combustion turbine extracts shaft power

from the combustion of fuel and spins

an electric generator to generate

electricity. The hot exhaust gases from

the combustion turbine are then routed

to a separate ‘‘waste heat recovery unit.’’

The waste heat recovery unit extracts

heat from the gases and generates steam

for use in a steam turbine, which in turn

provides shaft power to spin an electric

generator and generate electricity.

The combustion turbine in a

combined cycle system does not

generate steam. It is not a ‘‘steam

generating unit’’ and, therefore, is not an

‘‘electric utility steam generating unit.’’

However, we also conclude that,

because the waste heat recovery unit in

a combined cycle system does generate

steam, it is a steam generating unit.

Whether a waste heat recovery unit in

a new or reconstructed combined cycle

system is subject to a case-by-case

MACT is a moot point in many cases

because the waste heat recovery unit is

not an emission source. The emissions

from the combustion turbine pass

through the waste heat recovery unit,

but the waste heat recovery unit is not

a source of additional emissions.

There is another type of combined

cycle system, however, in which the

waste heat recovery unit does contribute

additional emissions. In these types of

combined cycle systems, fuel is burned

in the duct, through the use of ‘‘duct

burners,’’ just before the gases enter the

waste heat recovery unit.

These duct burners are analogous to

the burners in steam generating units

(i.e., boilers). Their only purpose is to

burn fuel to generate more heat for

extraction by the waste heat recovery

unit in order for it to generate more

steam. As a result, duct burners (where

they are used) are considered part of the

waste heat recovery unit in a combined

cycle system—just as the burners in a

boiler are considered part of the boiler.

Duct burners in combined cycle

systems normally burn natural gas.

Although it is unlikely that sufficient

natural gas would be burned in a duct

burner in a combined cycle system to

result in emissions that would

themselves exceed the major source

threshold, a combined cycle system may

have aggregate emissions which exceed

the major source threshold. Therefore,

in each instance where a stationary

combustion turbine in a combined cycle

system must meet MACT requirements

because it is a major source of HAP, an

associated duct burner will also be

subject to MACT requirements unless it

is found to be an electric utility steam

generating unit. It is also possible that

there could be instances where

emissions from a duct burner in a waste

heat recovery unit which is not an

electric utility steam generating unit

could cause the total emissions from a

combined cycle system to exceed the

major source threshold.

If the waste heat recovery unit in a

combined cycle system operates with

duct burners, and more than one-third

of the potential electrical output

capacity of the duct burners and more

than 25 megawatts of the electrical

output provided by the duct burners are

provided to any utility power

distribution system for sale, then the

waste heat recovery unit is an electric

utility steam generating unit and is not

subject to case-by-case MACT

determinations unless and until such

units are added to the source category

list pursuant to CAA section 112(c)(5).

However, if the waste heat recovery unit

in a combined cycle system operates

with duct burners and less than onethird of the potential electrical output

capacity of the duct burners or less than

25 megawatts of the electrical output

provided by the duct burners are

provided to any utility power

distribution system for sale, then the

waste heat recovery unit must also meet

MACT requirements if the aggregate

HAP emissions from the combined cycle

system exceed the major source

threshold.

III. What Additional Information Is

Available?

As mentioned above, EPA is

developing MACT standards for

stationary combustion turbines. This

effort has resulted in collection of

information regarding the performance,

as well as the costs, associated with the

use of various technologies to reduce

emissions of HAP from stationary

combustion turbines.

In conjunction with today’s

interpretative rule, EPA is making

available two memoranda, the first

entitled, ‘‘Hazardous Air Pollutant

(HAP) Emission Control Technology for

New Stationary Combustion Turbines,’’

and the second entitled, ‘‘Oxidation

Catalyst Costs for New Stationary

Combustion Turbines.’’ These two

memoranda compile and summarize

information collected by EPA and may

be of assistance in making any required

case-by-case MACT determinations.

These memoranda may be obtained by

contacting EPA as shown under FOR

FURTHER INFORMATION CONTACT or

downloaded directly by logging on to

the following EPA website: http://

www.epa.gov/ttn/uatw/combust/

turbine/turbpg.html.

34012 Federal Register / Vol. 65, No. 102 / Thursday, May 25, 2000 / Rules and Regulations

IV. Why Is EPA Withdrawing the

Interpretative Rule Published on April

21, 2000?

An error by EPA led to publication of

a preliminary draft of the interpretative

rule on April 21, 2000 at 65 FR 36321.

V. What Are the Impacts Associated

With This Interpretative Rule?

As mentioned above, this

interpretative rule simply resolves

current ambiguity concerning the

applicability of CAA section 112 to new

or reconstructed major source stationary

combustion turbines. It is not intended

to subject these entities to any new or

additional regulatory requirements.

VI. What Is the Applicability of Other

Review Requirements?

Under Executive Order 12866 (58 FR

51736, October 4, 1993), this

interpretative rule is not a ‘‘significant

regulatory action’’ and is, therefore, not

subject to review by the Office of

Management and Budget.

Section 553(b)(3)(A) of the

Administrative Procedure Act provides

that interpretative rules are not subject

to notice-and-comment requirements.

Interpretative rules which do not

involve the internal revenue laws of the

United States are not subject to the

regulatory flexibility provisions of the

Regulatory Flexibility Act (5 U.S.C. 601

et seq.). Because notice-and-comment

requirements do not apply to this

interpretative rule, this rule is also not

subject to sections 202 and 205 of the

Unfunded Mandates Reform Act of 1995

(UMRA) (2 U.S.C. 1532 and 1535).

In addition, this action does not

significantly or uniquely affect small

governments or impose a significant

intergovernmental mandate, as

described in sections 203 and 204 of

UMRA. This interpretative rule also

does not significantly or uniquely affect

the communities of tribal governments,

as specified by Executive Order 13084

(63 FR 27655, May 10, 1998). This

interpretative rule will not have

significant direct effects on the States,

on the relationship between the national

government and the States, or on the

distribution of power and

responsibilities among the various

levels of government, as specified in

Executive Order 13132 (64 FR 43255,

August 10, 1999).

This interpretative rule is also not

subject to Executive Order 13045 (62 FR

19885, April 23, 1997) because it is not

economically significant. This action

does not involve technical standards;

thus, the requirements of section 12(d)

of the National Technology Transfer and

Advancement Act of 1995 (15 U.S.C.

272 note) do not apply. This

interpretative rule also does not involve

special consideration of environmental

justice related issues as required by

Executive Order 12898 (59 FR 7629,

February 16, 1994).

In issuing this interpretative rule, EPA

has taken the necessary steps to

eliminate drafting errors and ambiguity,

minimize potential litigation, and

provide a clear legal standard for

affected conduct, as required by section

3 of Executive Order 12988 (61 FR 4729,

February 7, 1996). The EPA has

complied with Executive Order 12630

(53 FR 8859, March 15, 1988) by

examining the takings implications of

the interpretative rule in accordance

with the ‘‘Attorney General’s

Supplemental Guidelines for the

Evaluation of Risk and Avoidance of

Unanticipated Takings’’ issued under

the Executive Order. This interpretative

rule does not impose an information

collection burden under the provisions

of the Paperwork Reduction Act of 1995

(44 U.S.C. 3501 et seq.). The EPA’s

compliance with these statutes and

Executive Orders for the underlying rule

interpreted herein is discussed in the

March 29, 1996 Federal Register

document (61 FR 14029).

The Congressional Review Act, 5

U.S.C. 801 et seq., as added by the Small

Business Regulatory Enforcement

Fairness Act of 1996, generally provides

that before a rule may take effect, the

agency promulgating the rule must

submit a rule report, which includes a

copy of the rule, to each House of the

Congress and to the Comptroller General

of the United States. We have

established an effective date of June 26,

2000. The EPA will submit a report

containing this rule and other required

information to the U.S. Senate, the U.S.

House of Representatives, and the

Comptroller General of the United

States prior to publication of the rule in

the Federal Register. This rule is not a

‘‘major rule’’ as defined by 5 U.S.C.

804(2).

List of Subjects in 40 CFR Part 63

Environmental protection, Air

emissions control, Hazardous air

pollutants, Combustion turbines.

Dated: May 18, 2000.

Robert Perciasepe,

Assistant Administrator, Office of Air and

Radiation.

[FR Doc. 00–13196 Filed 5–24–00; 8:45 am]

BILLING CODE 6560–50–P

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 63

[AD–FRL–6706–2]

National Emission Standards for

Hazardous Air Pollutants for Source

Categories

AGENCY: Environmental Protection

Agency (EPA).

ACTION: Withdrawal of interpretative

rule.

SUMMARY: The EPA is withdrawing the

interpretative rule published in the

Federal Register on April 21, 2000, at

65 FR 21363. That interpretative rule

was intended to clarify the construction

by EPA of the applicability of sections

112(g) and 112(j) of the Clean Air Act

(CAA) to all stationary combustion

turbines and waste heat recovery units

in combined cycle systems.

An administrative error led to

publication of a preliminary draft of the

interpretative rule, rather than the final

interpretative rule EPA intended to

publish. Concurrent with this

withdrawal of the incorrect version of

the interpretative rule published on

April 21, 2000, EPA is publishing

elsewhere in today’s Federal Register a

corrected version of the interpretative

rule.

DATES: On May 25, 2000, EPA hereby

withdraws the interpretative rule

published at 65 FR 21363. The corrected

interpretative rule will become legally

effective on June 26, 2000.

FOR FURTHER INFORMATION CONTACT: For

further information, contact Sims Roy,

Combustion Group, Emission Standards

Division (MD–13), U.S. Environmental

Protection Agency, Research Triangle

Park, North Carolina 27711, telephone

number: (919) 541–5263, facsimile:

(919) 541–5450, electronic mail address:

roy.sims@epa.gov.

Dated: May 18, 2000.

Robert Perciasepe,

Assistant Administrator, Office of Air and

Radiation.

[FR Doc. 00–13197 Filed 5–24–00; 8:45 am]

BILLING CODE 6560–50–P