67788 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

stated above, the only reporting

requirements are an initial report that

allows the EPA to determine the

universe of regulated entities, and

reports that explain date codes if such

codes are used to indicate the date of

manufacture. The EPA believes that

minimization of recordkeeping and

reporting requirements will help to

decrease impacts upon small entities.

For the foregoing reasons, the EPA

anticipates that the proposed rule will

not have a significant impact on a

substantial number of small entities.

The EPA believes that this conclusion is

appropriate with respect to all entities

to be regulated under the proposed rule,

including the component manufacturers

and importers encompassed by this

supplemental proposal.

Unfunded Mandates Act of 1995

Under section 202 of the Unfunded

Mandates Reform Act of 1995

(‘‘Unfunded Mandates Act’’), signed

into law on March 22, 1995, the EPA

must prepare a budgetary impact

statement to accompany any proposed

or final rule that includes a Federal

mandate that may result in estimated

costs to State, local, or tribal

governments in the aggregate, or to the

private sector, of $100 million or more.

The EPA has determined that today’s

action does not include a Federal

mandate that may result in estimated

costs of $100 million or more to either

State, local, or tribal governments in the

aggregate, or to the private sector.

Therefore, the requirements of section

202 of the Unfunded Mandates Act do

not apply to this action.

Electronic Submission of Comments

Comments may be submitted

electronically by sending electronic

mail (e-mail) to: a-and-rdocket@epamail.epa.gov. Electronic

comments must be submitted as an

ASCII file, avoiding the use of special

characters and any form of encryption.

Comments will also be accepted on

diskette in WordPerfect 5.1 or ASCII file

format. All comments in electronic form

must be identified by the docket number

A–95–18. No Confidential Business

Information (CBI) should be submitted

through e-mail. Electronic comments

may be filed online at many Federal

Depository Libraries.

List of Subjects in 40 CFR Part 59

Environmental protection, Air

pollution control, Automobile refinish

coatings, Consumer and commercial

products, Volatile organic compounds.

Dated: December 9, 1997.

Richard D. Wilson,

Acting Assistant Administrator for Air and

Radiation.

[FR Doc. 97–33963 Filed 12–29–97; 8:45 am]

BILLING CODE 6560–50–P

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Parts 60 and 63

[FRL–5941–4]

Total Mercury and Particulate

Continuous Emissions Monitoring

Systems; Measurement of Low Level

Particulate Emissions; Implementation

at Hazardous Waste Combustors;

Proposed Rule—Notice of Data

Availability and Request for Comments

AGENCY: Environmental Protection

Agency (EPA).

ACTION: Notice of data availability and

request for comments.

SUMMARY: This announcement is a

notice of data availability and invitation

for comment on the following reports

pertaining to total mercury and

particulate continuous emissions

monitoring systems: DRAFT: Total

Mercury CEMS Demonstration,

Summary Table, dated December 1997;

and DRAFT: Particulate Matter CEMS

Demonstration, Volume I (with

appendices), dated December 1997. EPA

proposed requiring these monitors for

hazardous waste combustors in the

hazardous waste combustor proposed

rule published on April 19, 1996. In

addition, this document discusses

topics for implementing particulate

matter continuous emissions monitoring

systems at hazardous waste combustors.

Readers should note that only

comments about new information

discussed in this document will be

considered. Issues related to the April

19, 1996, proposed rule and subsequent

documents that are not directly affected

by the documents or data referenced in

this Notice of Data Availability are not

open for further comment.

DATES: Written comments on these

documents and this document must be

submitted by January 29, 1998.

ADDRESSES: Commenters must send an

original and two copies of their

comments referencing Docket Number

F–97–CS6A–FFFFF to: RCRA Docket

Information Center, Office of Solid

Waste (5305G), U.S. Environmental

Protection Agency Headquarters (EPA,

HQ), 401 M Street, SW, Washington,

D.C. 20460. Comments may also be

submitted electronically through the

Internet to: rcradocket@epamail.epa.gov. Comments in

electronic format should also be

identified by the docket number F–97–

CS6A–FFFFF. All electronic comments

must be submitted as an ASCII file

avoiding the use of special characters

and any form of encryption.

Commenters should not submit

electronically any confidential business

information (CBI). An original and two

copies of the CBI must be submitted

under separate cover to: RCRA CBI

Document Control Officer, OSW

(5305W), 401 M Street, SW, Washington

D.C. 20460.

For other information regarding

submitting comments electronically,

viewing the comments received, and

supporting information, please refer to

the proposed rule (61 FR 17358 (April

19, 1996)). The RCRA Information

Center is located at Crystal Gateway

One, 1235 Jefferson Davis Highway,

First Floor, Arlington, Virginia and is

open for public inspection and copying

of supporting information for RCRA

rules from 9:00 a.m. to 4:00 p.m.

Monday through Friday, except for

Federal holidays. The public must make

an appointment to view docket

materials by calling (703) 603–9230. The

public may copy a maximum of 100

pages from any regulatory document at

no cost. Additional copies cost $0.15

per page.

FOR FURTHER INFORMATION CONTACT: For

general information, call the RCRA

Hotline at 1–800–424–9346 or TDD 1–

800–553–7672 (hearing impaired)

including directions on how to access

some of the documents and data

referred to in this notice electronically.

Callers within the Washington

Metropolitan Area must dial 703–412–

9810 or TDD 703–412–3323 (hearing

impaired). The RCRA Hotline is open

Monday-Friday, 9:00 a.m. to 6:00 p.m.,

Eastern Time.

The documents referred to in this

notice are available over the Internet.

The documents can be accessed by

typing the following universal resource

locator (URL):

http://www.epa.gov/epaoswer/

hazwaste/combust/cems

This URL provides a home page

through which all electronically

available documents can be

downloaded. The Technology Transfer

Network (TTN) also provides a link to

this page. CEMS information is available

on TTN at the following URL:

http://ttnwww.rtpnc.epa.gov/html/

emtic/cem.htm

The home page contains links to the

files that are available electronically.

The files are in an executable,

compressed format to facilitate
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67789

downloading. Once extracted, each

compressed file may result in more than

one decompressed file. The reports are

in Adobe Acrobat, PDF format. The

reader should note that figures,

diagrams, and appendices may not be

available electronically or may only be

available in other formats.

For other information regarding the

information contained in Sections I, II,

IV, and V of this notice, contact Mr.

Scott Postma, (5302W), Office of Solid

Waste, 401 M Street, SW, Washington,

D.C. 20460, phone (703) 308–6120, EMAIL: postma.scott@epamail.epa.gov.

For information regarding Section III of

this notice, contact Mr. H. Scott

Rauenzahn (5302W), Office of Solid

Waste, 401 M Street, SW, Washington,

D.C. 20460, phone (703) 308–8477, email: rauenzahn.scott@epamail.epa.gov.

SUPPLEMENTARY INFORMATION: On April

19, 1996, EPA proposed revised

standards (herein referred to as ‘‘the

proposed rule’’) for hazardous waste

combustors (HWCs, i.e., incinerators

and cement and lightweight aggregate

kilns that burn hazardous waste). See 61

FR 17358. Comments received from the

public in response to the proposed rule

are found in RCRA docket F–96–RCSP–

FFFFF.

A previous notice of data availability

(NODA), published on March 21, 1997,

gave the public the opportunity to

review the Agency’s approach to

demonstrating CEMS for HWCs. This

previous NODA is herein referred to as

‘‘the first CEMS NODA’’ or ‘‘CEMS

NODA 1.’’ See 62 FR 13776. Comments

received from the public in response to

the first CEMS NODA are found in

RCRA docket F–97–CS3A–FFFFF.

Readers should note that a separate

docket was established for this

document. See the ADDRESSES section

above for more information.

Table of Contents

I. Introduction and Background

II. The Hg CEMS Demonstration Tests

III. The PM CEMS Demonstration Tests

A. PM performance Specification (PS) 11

Levels

1. Revised Specification Levels for the

Correlation Coefficient, Confidence

Interval, and Tolerance Interval

2. Data Availability

3. Data Quality Objectives: New

Procedures to Appendix F of 40 CFR Part

60

B. Manual Method Accuracy

1. Modification of the Filter Recovery

Process

2. Improved Sample Collection

3. Elimination of Contamination

4. Improved Sample Analysis

5. Comparison of M5 and M5i Method

Precision

6. Paired Data

C. Transferability of These Demonstration

Test Results to Other HWC Sources

IV. PM CEMS: Implementation and

Compliance

A. PM CEMS Compliance Schedule

B. PM CEMS Operating Parameter Limit

1. Introduction

2. Data Excluded from Calculating the PM

CEMS Operating Parameter Limit

3. Determining the Normality of the Data

4. Averaging Periods for the PM CEMS

Operating Parameter Limit

5. Options for Calculating the PM CEMS

Operating Parameter Limit

a. Using rank statistics to calculate the

PM CEMS-based operating parameter

limit at one, fixed averaging period

b. The traditional standard setting

approach

6. Consideration of a Variance Procedure

to Project a Higher PM CEMS Operating

Parameter Limit

a. HAPs for which PM control is

necessary to ensure compliance

b. Projecting a higher PM CEMS operating

parameter limit considering the ratio of

the standard to the measured level of a

HAP

c. Ensuring that the higher projected PM

CEMS operating parameter limit does not

exceed the MACT PM standard

d. Establishing revised operating

parameter limits for the PM control

device corresponding to the higher

projected PM CEMS operating parameter

limit

e. Implementing the variance

7. EPA’s PM CEMS Testing to Identify a

CEMS-Based Emission Level Achievable

by MACT-Controlled Sources

C. RCA Test Frequency

D. Extrapolating PM CEMS Calibration

Data

1. Extrapolating Light-Scattering PM

CEMS Calibration Data

2. Extrapolation of Beta-gage Calibration

Data

E. Need to Calibrate to Twice the

Emission Standard

F. Allowing PM CEMS to be Used In-lieu

of Method 5 Tests

G. Waivers from the PM CEMS

Requirements

1. Waiver of PM and Hg CEMS

Requirements for Small On-Site

Incinerators

2. PM CEMS Waiver for Sources with

Short Life-Spans

3. Other Sources

V. Other Issues Concerning CEMS and Test

Methods for HWCs

A. Performance Specifications for

Optional CEMS

B. Stack Sampling Test Methods

PART 60—STANDARDS OF

PERFORMANCE FOR NEW STATIONARY

SOURCES

I. Introduction and Background

In the proposed rule, EPA proposed

that continuous emissions monitoring

systems (CEMS) be used for compliance

with the HWC total mercury (Hg) and

particulate matter (PM) standards. See

61 FR at 17426 and 17435. To require

CEMS for compliance the Agency,

among other things, must determine that

the CEMS are commercially available

and have been demonstrated to meet

certain performance specifications. To

make these determinations, the Agency

tested various Hg and PM CEMS being

marketed in the U.S. and Europe. The

first CEMS NODA described the

approach EPA is using to demonstrate

the feasibility of PM and Hg CEMS and

requested comment on certain technical

issues arising from this program. This

testing is now complete. Today the

Agency is providing notice of an

opportunity to comment on the

following documents resulting from

these CEMS demonstration test

program: DRAFT: Total Mercury CEMS

Demonstration, Summary Table, dated

December 1997; and DRAFT: Particulate

Matter CEMS Demonstration, Volume I

(with appendices), dated December

1997.

The remainder of this notice describes

important information bearing upon

how the reports’ results relate to EPA’s

approach to demonstrating Hg and PM

CEMS and how PM CEMS could be

used for compliance. Many of these

issues were raised by commenters in

response to CEMS NODA 1 and the

proposed rule. The reader is referred to

the referenced documents for specific

information regarding the Hg and PM

CEMS demonstration test program and

the comments cited here.

II. The Hg CEMS Demonstration Tests

EPA seeks comment on the document

DRAFT: Total Mercury CEMS

Demonstration, Summary Table, dated

December 1997, provided in the above

referenced docket for this NODA. This

table summarizes results from the Hg

CEMS demonstration tests EPA

conducted.

In summary, the Agency found certain

aspects of the testing program revealed

substantial problems regarding the

measurement of the Hg CEMS accuracy

and precision. EPA found it difficult to

dynamically spike known amounts of

mercury (in the elemental and ionic

form) and obtain manual method and

Hg CEMS measurements that agree at

the test source. As a result, the Agency

now believes it has not sufficiently

demonstrated the viability of Hg CEMS

as a compliance tool at all hazardous

waste combustors and should not

require their use. Nonetheless, EPA still

believes Hg CEMS can and will work at

some sources but does not have

sufficient confidence that all HWC

conditions are conducive to proper

operation of the Hg CEMS tested.

Facilities should have the choice of

using Hg CEMS if desired so long as the
67790 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

1This technology did meet 10 of the 14

specification comparisons.

2The correlation coefficient is defined as the ratio

Sxy divided by the square root of the quantity Sxx

times Syy. Sxy is a measurement of error as x relates

to y, while Sxx and Syy are a reflection of the range

of the data set. As a result, the correlation

coefficient is not as useful a tool to evaluate

measurement error as the correlation and tolerance

intervals. This is particularly true as the correlation

coefficient approaches 1.

permitting agency approves on a sitespecific basis the Hg CEMS and its sitespecific performance specifications. See

a related issue in section V.A. of this

NODA regarding the implementation of

optional CEMS.

III. The PM CEMS Demonstration Tests

This section describes the report

DRAFT: Particulate Matter CEMS

Demonstration, Volume I (with

appendices), dated December 1997,

contained in the docket identified in the

Addresses section, above. EPA issued

previous notices asking vendors to

participate in this program (see 61 FR

7232, February 27, 1996) and to allow

the public to comment on the Agency’s

approach to demonstrating these

monitors (see 62 FR 13775, March 21,

1997). Since this could represent the

first time EPA requires PM CEMS for

compliance at stationary sources, the

technical discussion contained in this

section is expected to have general

applicability beyond sources that burn

hazardous waste. In particular, EPA

invites comment from all parties

concerning the following documents

attached to this notice: Method 5I for

the determination of low level

particulate emissions; Performance

Specification 11 for PM CEMS; and

Quality Assurance Requirements for PM

CEMS.

A. PM Performance Specification (PS)

11 Levels

In CEMS NODA 1, the Agency stated

it intended to loosen the proposed PM

CEMS Performance Specification (PS)

11 to reflect what was achievable by the

monitors during this demonstration test.

The test was designed to be a reasonable

worst case investigation of what

performance (relative to the proposed

PS11) the monitors could achieve. Many

comments received in response to

CEMS NODA 1 stated that the proposed

performance specifications were not

sufficiently stringent and opposed

loosening the specification levels.

Concurrent with the Agency’s

invitation in CEMS NODA 1 to

comment on our approach to

demonstrate PM CEMS, EPA

determined that much of the variability

in the calibration curves resulted from

inaccuracies in performing the manual

method, Method 5 (M5). Since the

fundamental approach in PS11 involves

correlating manual method results to

PM CEMS outputs, the PS11 statistical

results reflected this variability in the

manual method. Consequently, EPA

undertook a systematic effort to identify

and remove this error from the manual

method measurement process. Manual

method improvements were developed

and observed, and performance

specification results for the PM CEMS

improved as a result. (See a related

discussion in section III.B, below,

regarding these improvements to the

manual method.)

1. Revised Specification Levels for the

Correlation Coefficient, Confidence

Interval, and Tolerance Interval

As a result of comments on CEMS

NODA 1, EPA decided to accept a

slightly modified version of the more

stringent International Standards

Organization (ISO) specification 10155

for PM CEMS. Four of the five PM

CEMS tested during the PM CEMS

demonstration tests were able to meet

all three performance specifications

(i.e., those for the correlation coefficient

(r), confidence interval (CI), and

Tolerance Interval (TI)) at all three of

the emissions levels discussed in the

May 2, 1997, NODA as alternatives to

the proposed emissions standards (69

mg/dscm for cement kilns, 50 mg/dscm

for light-weight aggregate kilns, and 34

mg/dscm for hazardous waste

incinerators.) See 62 FR 24212 for a

discussion of those alternative

emissions standards. One technology,

an extractive light-scattering technology,

did not meet all the performance

specification levels at all of the

alternative standards.1 Since EPA must

show that at least one commercially

available PM CEMS can meet the

proposed performance specification, the

fact that 4 of the 5 monitors were able

to meet these performance levels under

reasonable worst-case test conditions

adequately shows that the modified

specification levels are achievable. The

revised performance specification levels

are presented in Table 1, below.

TABLE 1: REVISED PERFORMANCE

SPECIFICATIONS FOR PM CEMS

Correlation coefficientConfidence

interval

Tolerance

interval

0.90 ±10% ±25%

As previously stated, these

performance levels are nearly identical

to the ISO specification for PM CEMS.

The only major difference between these

and the ISO specification levels is the

correlation coefficient, which is 0.95 in

ISO 10155 and 0.90 in the modified

PS11. This is acceptable since the

correlation coefficient does not directly

relate to measurement error while the

confidence and tolerance intervals do.2

The revised PS11 also requires that a

minimum of 15 runs be used for the

calibration while the ISO specification

requires only 9 runs. The ISO

specification is also vague regarding the

PM concentration ranges required for a

calibration. The revised PS11 stipulates

three ranges: 0 to 30, 30 to 60, and 60

to 100% of the facility’s range of PM

emissions.

2. Data Availability

EPA had proposed that PM CEMS be

used at all times that hazardous waste

is in the unit. See 61 FR at 17441.

Commenters to the proposed rule did

not view this favorably. They said this

proposal is equivalent to a 100% data

availability requirement for PM CEMS.

Commenters stated that this

requirement is not achievable since all

mechanical devices fail at some point,

often without warning. They said a data

availability requirement in the 85, 90, or

95% range would be more acceptable.

Commenters suggested that when the

PM CEMS were not available, the PMrelated operating parameter limits EPA

proposed should be used in place of the

PM CEMS.

EPA largely agrees with this

comment. The PM CEMS demonstration

tests show that a 100% data availability

requirement is not achievable for all PM

CEMS in all instances. The Agency also

agrees that when PM CEMS are not

operating, it is reasonable to provide for

some back-up compliance system in lieu

of requiring sources to either stop

burning hazardous waste or have a backup PM CEMS available. The PM APCD

operating parameters proposed in the

event there is no PM CEMS requirement

are a good starting point for identifying

such a back-up system. See the

discussion later in this section for more

information on this issue.

Based on these demonstration tests

and the comments received, EPA

concludes that a 95% data availability

requirement is achievable for most PM

CEMS. Therefore, EPA intends that PM

CEMS be used 95% of the time for

compliance. However, there are useful

technologies that cannot meet this 95%

data availability requirement. This data

availability requirement should be

relaxed in certain instances. For

instance, beta-gages did not meet the

95% data availability requirement

during the PM CEMS tests. EPA believes

beta-gages, with their relatively superior
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67791

3One of the beta gage PM CEMS experienced a

74% data availability during the PM CEMS

demonstration test program. Much of the additional

downtime was because no U.S.-based technicians

were fully trained to service this instrument during

this program and parts and personnel had to be

brought to the U.S. Once EPA requires a new

technology, such as PM CEMS, the market for that

new technology is expected to mature in the US

similar to how one exists overseas. As a result, data

availability will be better than what was

experienced here.

performance and ability to measure PM

emissions at truly wet stacks (i.e., those

with entrained water droplets in the

stack gas), will be useful at some

sources for compliance. Therefore, EPA

will consider an 85% data availability

requirement for beta-gage technology

PM CEMS.3 The Agency anticipates

other case-by-case determinations will

be made in the future as more is learned

about the performance, benefits, and

data availability limitations of other PM

CEMS technologies. Finally, EPA believes that increasing

the amount of PM data available will

enable sources to improve their

understanding and better define the

relationship between operating

parameters and emission levels. EPA is

aware of two relevant examples which

are described here. The first one is an

ongoing cooperative effort with

industry, regulatory agencies, and the

local public. This effort is focused on a

venturi scrubber-controlled lime kiln at

a pulp and paper plant where testing is

being conducted to evaluate the

feasibility of a predictive emission

monitoring system (PEMS). Following

preliminary measurements and an

experimentally designed test matrix,

595 Method 5 runs were performed over

a wide variety of process and scrubber

operating conditions, and PM emission

levels. A correlation coefficient above

0.9 was obtained in correlating PM

emission levels with 54 operating

parameters. In comparison, use of PM

CEMS represents a powerful tool for

accumulating much data at a cost that

is far less than performing hundreds of

Method 5 runs. As a result, PM CEMS

allow for a cost-effective way to

implement a PM PEMS model than

making hundreds of Method 5

measurements.

The second example directly relates

to the first. The Electric Power Research

Institute (EPRI) has already produced a

means to characterize and correlate PM

emissions with operating conditions at

coal-fired utility boilers. PM emissions

from utility boilers are similar to HWCs

in that their emissions are affected by a

complexity of variations from a number

of fuel and feed characteristics,

combustor operations, and electrostatic

precipitator (ESP) operations. As in the

lime kiln case mentioned above, use of

PM CEMS represents a more powerful

tool for accumulating and correlating

vast amounts of PM emission data with

PM-related operating parameters at a

cost that is far less than performing a

large number of Method 5 runs. These two examples, therefore, lead

EPA to believe that a PM CEMS

requirement will allow HWC facilities to

better define what PM APCD operating

parameter limits correspond to a given

PM emissions concentration. As a

result, the Agency encourages HWC

facilities to use PM CEMS data to better

define what operating parameters

correspond to compliance with a

facility’s PM CEMS limit. The sitespecific limit is discussed further in

section IV.B. of this notice.

3. Data Quality Objectives: New

Procedure 2 to Appendix F of 40 CFR

Part 60

EPA intends to expand the ISO

specification to include certain data

quality objectives. For example, PM

CEMS routinely and automatically

check and correct their raw outputs to

compensate for phenomena such as

‘‘fogging’’ of the optics and drift of the

measurement signal. A large and sudden

auto correction is indicative of the need

to perform maintenance on the PM

CEMS. To address this concern, EPA

intends to include certain data quality

objectives such as: The (PM CEMS

internal) calibration drift not exceed 8%

during any drift check; the (PM CEMS

internal) calibration drift not exceed

more than 4% per day for five

consecutive days; and the automated

(PM CEMS internal) calibration drift

adjustment not exceed 2% for five

consecutive days. These data quality criteria would

appear in a new Procedure 2 of

Appendix F to 40 CFR part 60. Just as

Procedure 1 of Appendix F deals with

data quality objectives for gaseous

CEMS for other CAA rules (CEMS such

as NOX and SOX), Procedure 2 would

address data quality objectives for PM

CEMS. Procedure 2 would also include

the following data quality objectives:

treatment of ‘‘flagged data;’’ PM CEMS

automatic zero and calibration span

requirements; conduct of the Absolute

Calibration Audit and the quality of the

standards used for these audits; sample

volume audit requirements for

extractive systems; relative calibration

audit (RCA) requirements; the treatment

of audit failures; how manual method

paired data outliers (see the CEMS

NODA 1, 62 FR at 13780) are handled;

definition of ‘‘out-of-control’’ situations;

and how facilities are to respond to

these ‘‘out-of-control’’ situations. See

Procedure 2 (which appears at the end

of this notice) and the draft final PM

CEMS Demonstration Test Report for

more information regarding these

requirements and Procedure 2.

B. Manual Method Accuracy

One outgrowth of these PM CEMS

demonstration tests is that EPA has

made significant improvements in

making Method 5 particulate

measurements. As previously

mentioned, the calibration process for

PM CEMS involves correlating PM

CEMS outputs to manual method

results. High variability in the manual

method results will negatively affect the

PS11 calibration statistics. Therefore,

one important way to improve PS11

statistics is to improve the way manual

method measurements are made. These

improvements involve the use of a new

Method 5I (M5i) for low level PM

emissions. M5i consists of the following

improvements: improved sample

collection; elimination of possible

contamination; and improved sample

analysis. Each will be discussed in the

following paragraphs. M5i will be

instrumental in correlating PM CEMS

outputs to manual method results. EPA

also expects this new method will be

preferred in all cases where low level

(i.e., below 45 mg/dscm [∼0.02 gr/dscf])

measurements are required. In practice,

this means that M5i is expected to

become the standard method for most

HWCs and many other MACT sources.

EPA expects many of the improvements

in M5i can and will be implemented

whenever Method 5 (collectively,

including Method 5, 5A, ..., 5H) is used

to make particulate measurements.

M5i is almost identical to the

traditional M5. Differences are

discussed below. We also present a

comparison of the precision of M5i

(which fully implements these

improvements) and the traditional M5

(which largely does not use these

improvements) and discuss the need for

and handling of paired M5 data.

1. Modification of the Filter Recovery

Process

One way M5i differs from the

traditional M5 is through the use of a

light-weight and integrated filter and

filter assembly that can be tared and

weighed together. This improves M5 by

eliminating the filter recovery step. The

filter recovery step can be a significant

source of measurement error at some

sources. In some cases as the filter dries,

the filter adheres itself to the filter

assembly. Recovery of the filter then

involves scraping the filter off the filter

assembly leaving some of the filter (and

sample) on the filter assembly or

otherwise losing it to the environment.

In other cases, the filter recovery
67792 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

4As humidity levels decrease, static charge tends

to increase. The elimination of static charge,

previously discussed, will aid at eliminating this

problem.

process can lead to the loss of sample

to the environment as light-weight

particles are lost to the air during

handling. It can also lead to

contamination of the sample in cases

where fugitive dust from the

environment lands on the filter during

the recovery step. Simplifying the

recovery step through the use of a lightweight, integrated filter and assembly

addresses these concerns and thereby

improves the reliability of making PM

measurements.

One consequence of this

improvement, though, is that the filter

used M5i is smaller than that used in

the traditional M5 (47 mm compared to

approximately 90 to 100 mm in the

traditional M5). This smaller filter can

plug at higher emissions levels. For this

reason, this aspect of M5i may not be

implementable at sources with

emissions above 45 mg/dscm (that is,

total train catches exceeding 50 mg).

2. Improved Sample Collection

Another important improvement to

M5 is to the sample collection process

itself. These improvements include:

ensuring that the nozzle is 90° to the

direction of flow at each traverse

location; and using Pesticide Grade (i.e.,

low residue) acetone for probe rinse.

Each is discussed in the following

paragraphs. These improvements to the

sample collection process may also be

implemented over time into other

versions of Method 5.

Test crews routinely check the ‘‘level’’

of the probe only once during

sampling—prior to or at the beginning

of the sampling process itself. As the

traverse progresses, the probe can

become ‘‘unlevel,’’ i.e., it is no longer at

a right (90°) angle to the direction flow

in the stack gas. As the angle of the

probe departs from 90°, inconsistent

amounts of sample are collected and

thereby causes error in M5

measurements. This can be corrected by

applying a level to the sample probe and

checking the level continuously

throughout the traverse. Ensuring that

the probe angle is constant and level

throughout the traverse eliminates this

potential source of measurement error.

Finally, residue contained in the

acetone used for the probe rinse is

another source of sampling error.

Acetone is used for the probe rinse since

it is a solvent that evaporates readily at

room temperatures and thereby allows

rapid weighing of the specimen

following sampling. The standard M5

procedures require that acetone residue

blank levels be determined and that

reagent-grade acetone in glass bottles

with no more than 0.001% residue be

used for probe rinses. Acetone comes in

many grades, including reagent grade,

depending on how the purchaser

intends to use the acetone. Some grades

of acetone contain higher levels of

residue. This residue remains after the

acetone evaporates and contaminates

the probe rinse, making the ‘‘catch’’

during the probe rinse greater than what

it really is. Acetone blanks above

0.001% are not allowed by M5, so the

acetone itself must have a concentration

of residue no more than this

requirement for the blanks. M5 also

requires that the acetone be stored in

glass containers because acetone from

metal containers generally have a high

residue blank level. Test crews routinely

use reagent-grade acetone purchased in

small, glass containers since large

quantity purchases create a fire safety

and storage issue. Though ordered with

the intent of meeting specifications,

acetone suppliers often store bulk,

reagent grade acetone in metal

containers and transfer this acetone to

glass containers only to ship the small

quantities sold. This means that the

residue concentrations found in reagent

grade acetone are often higher than what

is allowed by M5. The unallowable

amount of residue from high blank

levels would have a negative effect on

the accuracy and precision of M5

results. This can be avoided by

requiring low-residue, Pesticide grade

acetone.

3. Elimination of Contamination

In a general sense, eliminating

contamination in the filter handling

processes will eliminate potential

sources of error. Contamination can be

avoided by: using a portable desiccator

for use in transporting and holding the

filters to and on the stack; using glass

plugs on the filter assemblies to keep

them ‘‘pure’’ prior to and after sampling;

covering the desiccant with a 0.1 micron

screen to eliminate potential external

contamination of filter housing during

transport; and handling the filter

assemblies with powder free latex

gloves. As previously discussed,

contamination in the M5 process will

make measured PM levels appear to be

higher than what they truly are. Each of

these steps to eliminate contamination

of the sample will ensure that fugitive

particulate from the environment does

not contaminate, thereby inadvertently

causing a positive bias to the measured

PM levels.

4. Improved Sample Analysis

Finally, improved sample analysis

will help eliminate error in the Method

5 measurement process. Specific steps

to improve M5 sample analysis include:

Elimination of all sources of static

charge (such as those on the operator,

beakers, liners, and balance); use of light

weight Teflon beaker liners for

gravimetric analysis of the probe rinse;

maintaining the laboratory area at a

humidity level of 30% or less; and

putting a covered desiccant container in

the balance weighing chamber. Each is

discussed in the following paragraphs.

High, varying levels of static charge

typically produce variations in repeated

weighing of susceptible materials such

as glass filter holder assemblies and

Teflon beakers (probe rinse catches).

The need for maintaining a relatively

dry atmosphere in the analytical room

further exaggerates the negative effect of

static charge on the weighing process.

To control and minimize the

consequences of static charge, EPA

found it was necessary to preclude any

and all aspects of static electricity. This

entailed using: (1) A static-free mat on

the floor area under the desiccator and

balance; (2) a small charge-neutralizer in

the desiccator; (3) another small chargeneutralizer in the weighing chamber of

the balance; and (4) a static dissipator

aerosol spray to prevent static buildup

on the Teflon beakers. EPA found it was

not possible to consistently reproduce

the same weight results (that is, within

0.5 mg) until all four measures were

done.

The particulate, filter assembly, and

filter are often hydrophilic in nature,

i.e., they tend to adsorb water from the

air. The amount of water these materials

adsorb depends on the amount of water

in the air. The moisture content of air

is often quantified in terms of the

relative atmospheric humidity, or what

percentage the actual water

concentration of the air is relative to the

saturation concentration. The higher the

relative humidity of the air, the more

water is adsorbed. The converse is also

true. As a result, if the relative humidity

in the analysis room is high, the amount

of water adsorbed onto the particulate,

filter, and assembly becomes variable

and it becomes increasingly difficult to

obtain a stable measurement. Ensuring

that the relative humidity in the

analysis room remains at a constant, low

level will ensure that the amount of

water adsorbed by these materials

remains relatively small and constant.

EPA found that maintaining the relative

humidity of the room to below 30% will

control this source of error.4

To further control and minimize the

adverse affects of humidity on

reproducing results in the weighing
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67793

5Only the filter, extraction, and weighing steps

were tested.

6For more on EPA’s rationale that this is a

reasonable worst-case test, see CEMS NODA 1 and

the PM CEMS Demonstration Test report sited here.

7See section 2.6.7 of the PM CEMS

Demonstration Test Report.

process, a small covered desiccant

container was placed in the balance’s

weighing chamber. This ensures that the

humidity level in the weighing chamber

is consistent with the humidity level in

the desiccator. The desiccant in the

weighing chamber dries fugitive air

entering the chamber from the room,

preventing the adsorption of room air

humidity on the materials being

weighed.

5. Comparison of M5 and M5i Method

Precision

M5i has been validated against

Method 5.5 It is also important to

quantify the improvements to M5 just

discussed. This can be done by

comparing the precision of both

methods at each of the three proposed

PM standards: 34, 50, and 69 mg/dscm

for hazardous waste burning

incinerators, LWAKs, and cement kilns,

respectively. Precision at the standards

is important since measurements at the

standard deal with compliance

determinations at facilities. The best

estimate of the standard deviation is

presented to represent this precision.

For M5i, the results presented are the

best estimate of the standard deviation

at each of the three proposed emissions

standards. These results are calculated

directly from the data obtained during

the PM CEMS demonstration tests. The

relative standard deviation (e.g., the best

estimate of the standard deviation at an

emissions concentration, divided by

that emissions concentration) for M5i is

in all cases less than 5%.

Historical data from Method 5 was

derived from PM concentrations ranging

from 80 to 255 mg/dscm. This data

indicates that the relative standard

deviation for M5 is constant at 10%.

Therefore, if one were to multiple the

emissions standard by 10%, one can

derive the best estimate of the standard

deviation at the three proposed

emissions standards.

Table 2, below, illustrates this

comparison and shows that M5i is an

improvement to M5.

TABLE 2: COMPARISON OF METHOD 5

AND METHOD 5i STANDARD DEVIATIONS

Proposed PM

emissions standard (mg/dscm) at

7% oxygen

Best estimate of the

standard deviation

(mg/dscm)

Method 5 Method 5i

34 3.4 1.67

50 5.0 2.24

TABLE 2: COMPARISON OF METHOD 5

AND METHOD 5i STANDARD DEVIATIONS—Continued

Proposed PM

emissions standard (mg/dscm) at

7% oxygen

Best estimate of the

standard deviation

(mg/dscm)

Method 5 Method 5i

69 6.9 2.85

6. Paired Data

Throughout most of the PM CEMS

demonstration tests, EPA used two

simultaneous Method 5i sampling

trains. These two simultaneous trains

are called ‘‘paired trains’’ and the paired

train data are called ‘‘paired data.’’ The

average of the paired data from the two

trains was considered the method result.

If the ‘‘paired data’’ differed by more

than 30% from the method result, EPA

eliminated the method result from the

calculation of the calibration.

EPA’s experience is that, despite the

efforts just discussed to control method

variability, intangibles which are

unknown or unquantifiable can cause

variability in M5 (and M5i)

measurements. Since it is important that

highly accurate M5 measurements be

obtained for calibrating PM CEMS, these

intangibles must be identified in some

way and data affected by these

intangibles must be eliminated from the

PM CEMS calibration. The fact that two

simultaneously run M5 (or M5i)

measurements do not agree is ample

evidence that something in the sample

collection and analysis process was not

consistent.

Comments received during the

comment period for CEMS NODA 1

stated that this process would not be

allowed if a facility were doing a

calibration for compliance. To address

this concern, EPA has incorporated this

outlier procedure in the new Procedure

2 and M5i. Having this procedure in the

regulations will allow facilities to

exclude this type of erroneous data from

their PM CEMS calibrations. Please note

that this procedure applies only if

paired data are obtained. Single

measurements obtained at different

times are not paired data. Single runs

cannot be eliminated by comparing

these results to other single

measurements.

EPA strongly encourages facilities to

use paired data during their

calibrations. Beyond the ability to

eliminate paired data outliers from the

PM CEMS calibration, using the average

of two runs as the method result has a

moderating affect on the calibration

statistics EPA calculated and used to

base the PS11 revised in today’s notice.

This moderating effect improves the

PS11 criteria relative to what they

would be if paired data were not used.

Some facilities may find it difficult to

obtain a suitable calibration using only

single M5 measurements. However,

while we encourage using paired data,

we are not requiring paired data for PM

CEMS calibrations. This choice can be

left to the facilities to determine what

makes the most economic and technical

sense at their site.

C. Transferability of These

Demonstration Test Results to Other

HWC Sources

EPA believes this demonstration test

program adequately shows that PM

CEMS will meet PS11 at most hazardous

waste incinerators, cement kilns, and

light-weight aggregate kilns. These tests

were conducted at a reasonable worstcase facility for performance relative to

the proposed performance

specifications6. Therefore, a PM CEMS

should pass the performance measures

described in the revised draft PS11 at

most HWC sources. The paragraphs

below discuss specific aspects of PM

CEMS and their applicability to each

HWC source category.

For cement kilns, in-situ light

scattering PM CEMS are operationally

very similar to continuous opacity

monitors (COMs), a technology

employed at these sources for many

years. Light-scattering PM CEMS differ

from COMs only in the way they obtain

and interpret the light from the source.

As shown in the LaFarge tests,7 though,

an informed decision is required to

determine what type of in-situ lightscattering PM CEMS is best suited for

these sources. One PM CEMS used at

LaFarge was built with a heated air

purge system to blow cement kiln dust

away from and out of the optics of the

monitor while the other was not. The

monitor with the heated air purge

performed very well over the course of

the tests, though improvements to the

Method 5 measurements and a routine

cleaning of the optics could have

improved performance. The PM CEMS

without the heated air purge suffered

operational difficulty. In addition, PM

from cement kilns is mostly process

dust (i.e., raw material). As such, its

physical properties are not significantly

affected by changes in waste or fuel

feeds. Accordingly, in-situ lightscattering PM CEMS will pass

performance specifications at cement

kilns if an informed decision is made to
67794 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

8The reader should note that HWCs are currently

regulated under RCRA. Sources with a different

regulatory history are likely to have a different

compliance regime than the one described here.

One should not assume that the compliance and

implementation scheme described here will

necessarily be applied to sources with a different

regulatory history.

9The Clean Air Act states that the Compliance

Date can be no more than three years after the

effective date of the rule (i.e., date of publication

in the Federal Register), unless a source obtains an

(up to) one-year time extension of the Compliance

Date.

purchase a monitor that is designed to

address the dusty environment at these

facilities.

EPA believes that LWAKs are very

similar to cement kilns relative to the

applicability of PM CEMS, and therefore

the conclusions drawn in the preceding

paragraph also apply to LWAKs.

For incinerators, there are certain

unique situations which must be

discussed: incinerators with truly wet

stacks; incinerators with waste heat

boilers; and mobile incinerators.

As was the case with cement kilns,

HWC incinerators with truly wet stacks

(i.e., those with entrained water droplets

in the stack gas) need to make an

informed choice regarding what PM

CEMS technology they elect to use. Insitu light-scattering PM CEMS are likely

to have operational difficulty since the

water droplets entrained in the stack gas

will be mistaken for particulate. This is

a readily accepted source of error and

means that in-situ light-scattering PM

CEMS are not a practical choice for

these sources. Beta-gage and certain

other light-scattering PM CEMS,

however, are designed with extractive

reheat systems which heat up the

extracted gas to above the water

condensation temperature. Incinerator

groups are currently working to test

these types of systems to gain first-hand

experience and data regarding the use of

PM CEMS at facilities with truly wet

stacks. EPA encourages these tests since

they will result in valuable data which

can be communicated to personnel at

incinerators with truly wet stacks to

assist their PM CEMS purchasing

decisions.

Incinerators equipped with waste heat

boilers (WHBs) downstream of the

combustion chamber(s) also require

special consideration. Like boilers, these

incinerators blow soot periodically to

clean the boiler tubes. PM emissions

will increase and the physical

properties (pertinent to PS11) of the PM

may change during periods of soot

blowing. To help address the impact of

soot-blowing, sources would be required

to include soot-blowing episodes during

a minimum of three calibration runs.

This will ensure that calibration

captures the higher emissions that can

occur during soot-blowing, thus

minimizing the need to extrapolate the

calibration curve beyond measured

values. In addition, including sootblowing during calibration runs will

enable the source to determine whether

any change in the physical properties of

the PM during soot-blowing has

adversely affected the calibration (i.e.,

as evidenced by an inability to meet PS

11 when the soot-blowing runs are

included).

EPA requests comment on this

approach to address the special

problems that soot-blowing may cause.

In particular, EPA seeks the following

information:

—How many incinerators are currently

equipped with WHBs? Are sources

likely to remove WHBs to facilitate

compliance with the MACT standards

(e.g., D/F)?

—The normal frequency and duration of

soot-blowing. Under what conditions

does the frequency and duration of

soot-blowing change? How often does

this change(s) occur?

—How do PM emissions for runs that

include episodes of soot blowing

compare to runs without soot

blowing?

—How does the effect of the APCS,

waste and fuel types, and other

relevant factors impact changes to the

PM concentrations and physical

properties when one compares PM

during soot-blowing and PM at other

times.

The reader should note that EPA

intends to promulgate MACT standards

for hazardous waste boilers as part of

Phase II of the HWC rulemaking. EPA

intends to address the applicability of

PM CEMS to boilers then. If because of

unforeseen reasons EPA provides a PM

CEMS waiver for incinerators with

WHBs, EPA would readdress the

applicability of PM CEMS to hazardous

waste incinerators with waste heat

boilers in Phase II.

Finally, another class of hazardous

waste incinerators are used at

Superfund sites during the clean-up

process. These mobile incinerators have

small, limited waste processing capacity

and are often trucked to the site as

needed. EPA is concerned that the

variability of the feed to mobile

incinerators is beyond what was

experienced at the DuPont facility. As

such, a unique calibration might be

required for every clean-up site, which

is unnecessarily burdensome. Given the

PM CEMS implementation schedule

discussed in section IV.A., below,

implementing PM CEMS at these

incinerators may not be feasible, and

EPA is considering whether to waive the

PM CEMS requirement for Superfund

mobile incinerators.

If the PM CEMS requirement is

waived for certain facilities, the other,

traditional operating parameters

discussed in this NODA would be used

instead to document compliance.

IV. PM CEMS: Implementation and

Compliance 8

A. PM CEMS Compliance Schedule

Many comments received in response

to the proposed rule stated that facility

personnel are not familiar with the

operation and maintenance

characteristics of PM CEMS, or how to

control their operating conditions to

ensure compliance using PM CEMS. For

this and reasons explained in section

IV.B., EPA plans to allow a 12-month

phase-in period before PM CEMS would

be used as a compliance parameter. This

section describes this compliance

schedule.

Prior to the date PM CEMS would be

used for compliance (i.e., during the 12-

month phase-in period), limits on key

PM-related and other key operating

parameters (e.g., metals feedrate) would

be used to ensure compliance with the

MACT standards for PM, SVM, and

LVM. This one year phase-in period has

four key milestones: The Compliance

Date; the performance Test Date; the

Certification of Compliance (CoC) date;

and the Certification of PM CEMS

performance date. By the Compliance

Date,9 facilities would determine, using

engineering judgment, the operating

parameter limits necessary to ensure

compliance with the standards. These

initial operating parameter limits would

be specified in a Precertification of

Compliance (Pre-CoC) that would be

submitted to the permitting authority by

the Compliance Date. By the Test Date,

which is nominally no later than six

months after the Compliance Date,

facilities would have to conduct a

performance test to document

compliance with the MACT emissions

standards and identify operating

parameter limits based on levels

achieved during the test. Results of the

performance tests and these revised

operating parameter limits would be

submitted to the permitting authority in

a Certification of Compliance (CoC)

nominally no more than nine months

after the Compliance Date. The

operating parameter limits in the CoC

would be used as surrogate compliance

measures to ensure that the efficiency of
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67795

10This would involve the verification that the

mathematical model used for the calibration is

correct, a recalculation of the ‘‘master’’ calibration

comprised of all three calibration curves, and a

revised site-specific PM CEMS operating parameter

limit (this time, using the first 12 months of data).

11 If the PM concentration and operating

parameter limits resulting from the subsequent

performance test are more stringent than those from

the previous test, the facility would have the option

of not recalculating their PM CEMS operating

parameter limit and continue to operate under the

older, more stringent limit.

the PM control device was maintained

at performance test levels until the oneyear anniversary date of the Compliance

Date. Beginning at that time, facilities

would start using the PM CEMS and

cease using the operating parameters as

their primary operating parameter for

PM control.

During this phase-in year, there are

important PM CEMS-related activities

being performed. For instance, the PM

CEMS, like all other equipment

necessary for compliance with the

MACT standards, must be installed by

the Compliance Date. Like all other tests

for the rule, the PM CEMS calibrations

and initial certifications (see section 8.3

of PS11 and section 4 of Procedure 2)

must also be performed by the Test

Date.

As discussed in the PM CEMS

Demonstration Test Report, the

mathematical characteristics of a lightscattering PM CEMS calibration curve

can be difficult to determine. For this

reason, a second calibration would be

required within 9 months of the

Compliance Date if a light-scattering PM

CEMS is used. After this second

calibration is performed the source

would compare the two calibrations

separately to determine which

mathematical model best represents the

data. This information (i.e., the analysis

of which mathematical model is best

suited for the calibration at this source

and the calibration comprised of all

valid calibration data obtained) would

be included in a Certification of PM

CEMS Performance (CoP) submitted

within 12 months after the Compliance

Date. (A CoP for beta-gage CEMS would

also be submitted at this time, but

would certify performance based on a

single calibration.)

This CoP would also include (for all

types of CEMS) the analysis of CEMS

data to identify an achievable CEMSbased PM operating parameter limit. See

section IV.B., below, for more

information regarding the PM CEMS

operating parameter limit. On the oneyear anniversary of the Compliance

Date, facilities would also cease using

the PM control device operating

parameter limits (such as pressure drop

across a fabric filter or total power input

to an ESP) and start using the PM CEMS

operating parameter limit as their

primary compliance parameter for the

PM control device.

A source using a light-scattering PM

CEMS would be required to perform a

third calibration of the PM CEMS within

12 months of the Compliance Date. The

third calibration would verify that the

mathematical model selected by

comparing the first two calibrations is

correct. If not, to the approach must be

modified based on the new data. If the

model needed to be revised, the source

would be required to recalculate the PM

CEMS operating parameter limit

considering the 12 months of data

following the Compliance Date. If the

model did not need to be revised, the

source could elect to recalculate the PM

CEMS operating parameter limit

considering the full 12 months of CEMS

recordings. (We request comment on

whether all sources required to perform

a third calibration should be required to

recalculate the PM CEMS operating

limit even if the calibration curve model

did not need to be revised.) The results

of the third calibration,10 reassessment

of the calibration model, and

recalculation of the PM CEMS operating

parameter limit would be submitted in

a second CoP. This second CoP would

be provided to the permitting authority

within 15 months of the Compliance

Date. Note that this second CoP would

not be required if a source uses a betagage type PM CEMS that needs only one

calibration. A source using a PM CEMS

that requires only one calibration (i.e., a

beta-gage) would have the option,

however, of submitting a second CoP if

it wants to update the PM CEMS

operating parameter limit based on a

full year of data.

Table 3 summarizes how PM CEMS

would be implemented for compliance.

Following this implementation

schedule, facilities would be required to

document compliance with the MACT

PM standard during periodic

performance testing. As discussed in

section IV.F. below, a source would

have the option of using the PM CEMS

or the manual method for this

determination. In addition, sources

would be required to recalculate their

PM CEMS operating parameter limit

based on the previous year of CEMS

data recorded when the source operated

within the operating parameter limits

established during the new performance

test. This recalculation of the PM CEMS

operating parameter limit is necessary

since the new performance test is likely

to result in numerically different PMrelated APCD operating parameters than

resulted from the previous test.11

Facilities would submit the revised

operating parameter limits, including

the revised PM CEMS operating

parameter limit, in a CoC describing the

results of the new performance test.
67796 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

12The Agency has proposed a MACT PM

standard as a surrogate to control emissions of nonenumerated metals HAPs (i.e., metal HAPs other

than those for which specific standards have been

proposed—Hg, SVM, and LVM). Those nonenumerated HAPs are Sb, Co, Mn, Ni, and Se.

13The Agency proposed that the site-specific PM

limit be a compliance parameter for the D/F

standard irrespective of whether activated carbon

injection was used as a control device. This

requirement was grounded upon EPA’s initial view

that a significant amount of D/F (and other heavy

organic compounds) are adsorbed onto particulate.

As a result, PM needed to be controlled to ensure

continuous compliance with the D/F standard. The

Agency is now considering comments that

significant D/F may not be adsorbed onto PM.

Cement and lightweight kiln PM, in particular, is

generally process dust (i.e., processed raw material).

This process dust has little affinity for adsorbing D/

F. However, EPA’s ultimate decision on whether to

limit PM on a site-specific basic does not depend

on whether there is a need to control PM at all

HWCs for D/F control. A site-specific PM limit is

still needed to ensure compliance with the SVM

and LVM standards at all HWCs. Sources that use

activated carbon injection, howver, would be

expected to have a significant amount of D/F on the

PM.

14Note that the MACT standard for PM would

continue to be a manual methods-based standard.

See subsection IV.F., below, for options facilities

could have to use PM CEMS for direct compliance

with this PM standard.

15The methods used for establishing CEMS

standards in the February 1991 MWC rule are

described in Appendices A and B of EPA document

number EPA–450/3–91–004, dated December 1990.

This document can also be found in the Air Docket,

located in the Mall area of EPA Headquarters, 401

M Street, SW, Washington, DC 20460. It is part of

docket number A–89–08–V–B–3.

TABLE 3: PM CEMS COMPLIANCE SCHEDULE

By this date These PM CEMS activities would be performed

Compliance date ...................................... PM CEMS installed

Precertification of Compliance (Pre-CoC) submitted that establishes PM APCD (and other) operating

parameter limits to ensure compliance with the SVM and LVM (and possibly D/F) standards based

on engineering judgment.

CD + 6 months (the ‘‘Test Date’’) ............ PM CEMS calibration tests performed during MACT performance test.

Method 5i used to demonstrate compliance with the manual method-based PM standard.

CD + 9 months ........................................ Certification of Compliance (CoC) submitted that establishes PM APCD (and other) operating parameter limits to ensure compliance with the SVM and LVM (and possibly D/F) standards based on

what levels were determined to correspond to compliance with the standard during the Performance Test. (These limits supersede those identified in the Pre-CoC.)

A second calibration of light-scattering PM CEMS is performed.

CD + 12 months ...................................... Source identifies calibration curve, calculates the PM CEMS operating parameter limit (through 9

months), recommends alternative PM control device operating parameters and their numerical limits, and submits a Certification of PM CEMS Performance (CoP).

Source ceases using PM control device operating parameters as the primary mode of compliance for

PM and starts using the PM CEMS. The operating parameters defined in the CoC are used for

compliance only when the PM CEMS is unavailable.

Source reports initial calibration (composite of all calibrations through 9 months), PM CEMS-based

limit, and revised operating parameter limits (for use during CEMS malfunctions) to permitting authority.

A third calibration of light-scattering PM CEMS is performed.

CD + 15 months ...................................... Sources using light-scattering PM CEMS revise the calibration curve if necessary based on the third

calibration, recalculate the PM CEMS operating parameter limit (through 12-months), update the

PM control device operating parameter limits for use during CEMS malfunctions, and submit a second CoP documenting this information.

The source starts using the revised operating parameters reported in the CoP during periods when

the PM CEMS is unavailable unless those alternatives have been disapproved by the permitting

authority.

B. PM CEMS Operating Parameter Limit

EPA proposed using site-specific

limits on key operating parameters of

the PM control device (e.g., pressure

drop across a fabric filter) to ensure that

the device maintained its collection

efficiency at performance test levels.

These limits, in combination with other

operating parameter limits (e.g., metals

feedrate controls) would ensure

compliance with the semivolatile metal

(SVM) and low volatile metal (LVM)

MACT standards. See 61 FR 17376 and

17430 (April 19, 1996). These operating

parameter limits on the PM control

device would also ensure compliance

with the MACT PM standard 12, and

possibly the MACT dioxin and furan (D/

F) and mercury (Hg) standards if the

source uses activated carbon injection to

control these HAPs. 13 The availability

of PM CEMS allows the Agency to

improve upon this approach through the

use of PM CEMS as the sole PM control

device operating parameter 14. PM CEMS

are a more sensitive and accurate

operating parameter than the

conventional PM-related operating

parameters now used.

This section describes how PM CEMS

would be implemented as an operating

parameter for the SVM, LVM, PM, and

possibly D/F and Hg standards. The

reader should note that the proposed

MACT standard for PM is and will

continue to be a manual methods-based

standard. The reader is referred to

section IV.F., below, for options a

facility could choose to use PM CEMS

as a direct indicator of compliance with

the MACT PM standard.

1. Introduction

The PM CEMS operating parameter

limit would be determined using the PM

CEMS data obtained during normal

operations from the Compliance Date to

the time when the calculation of the

operating parameter limit is performed.

Although the PM CEMS would be used

as an operating parameter limit here, an

approach to establishing this limit could

be very similar to how EPA establishes

national standards from CEMS data. The

municipal waste combustor rule

published on February 11, 1991, has an

example of how this is done 15.

EPA notes that even though the PM

CEMS operating parameter limit and the

manual methods-based PM standard are

both in units of particulate

concentration, it is likely that the PM

CEMS operating parameter limits will

have a different numerical value than

the manual methods-based MACT PM

standards. This is because the MACT

PM standards would be based on

manual methods testing with no fixed

averaging period. PM CEMS operating

parameter limits would have both a

fixed averaging period and a calculated
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67797

16For simplicity, EPA proposes to exclude data

from all periods in which the facility operated

outside of the operating envelope defined in the

CoC irrespective of whether the parameter in

question affects PM control. Defining what

operating parameters are or are not related to PM

control would force another layer of complexity in

this step.

17Episodes of high PM emissions caused by

periodic, routine maintenance cycles (e.g., ESP

rapping; soot-blowing for waste heat boiler

equipped incinerators, etc.) would not be

considered upset conditions. We request

information on how to objectively distinguish

between high PM emissions attributable to PM

control device upset conditions versus normal

emissions variability.

18The light-scattering CEMS provide

instantaneous data, recorded every minute as oneminute block averages. Beta-gage CEMS have

sampling periods longer than 1 minute.

19Note that batch CEMS, such as beta-gages, may

have sampling periods longer than 1 minute. In this

case, the test statistic would be performed using the

batch results.

20Three to 24 hours is within the range of CEMS

averaging periods EPA typically promulgates. From

a broader perspective, averaging periods vary from

regulation to regulation depending on the analysis

of issues pertaining to the technical, policy, and

regulatory history of each particular situation.

Therefore, other source categories may or may not

have the same averaging period as the one

established for PM CEMS at HWC, depending on

the outcome of this analysis of issues.

numerical limit. As discussed in section

4, below, the numerical value of a limit

or standard is a function of the

averaging period. Since it is likely that

the PM MACT standard and the PM

CEMS operating parameter would have

different averaging periods, one would

expect the numerical value of the PM

CEMS operating parameter limit that

indicates compliance with the MACT

standards would differ from the

numerical value of the MACT PM

standard.

2. Data Excluded From Calculating the

PM CEMS Operating Parameter Limit

Before calculating the PM CEMS

operating parameter limit, the PM CEMS

data set must be screened to remove PM

CEMS data recorded when the PM

CEMS was not available or the source

was out of compliance with the

operating parameter limits established

during the CoC.

First, the facility must remove from

the data set all PM CEMS data

accumulated while the PM CEMS was

not available or not performing

acceptably as defined by the regulations.

Examples of the data not included in the

calculation of the PM CEMS operating

parameter limit include data obtained

when the PM CEMS was ‘‘out-ofcontrol’’ as defined in Procedure 2 and

PS11, periods when the PM CEMS was

not analyzing stack gas (as would

happen during calibrations,

maintenance, etc.), and periods when

the facility was not in operation.

Next, the facility would further screen

the data to exclude times when the

facility was not operated in accordance

with the operating parameter limits

resulting from the performance test and

reported in the CoC16. Note that the CoC

operating parameter limits would

supersede the Pre-CoC operating

parameter limits for this screening

purpose. Although the Pre-CoC

operating parameter limits may be less

stringent than the CoC limits and were

valid limits prior to submitting the CoC,

the CoC limits are based on performance

testing and as such show what operating

parameter levels reflect compliance

with the standards. The facility must

also remove any data collected during

periods of PM APCS upset irrespective

of whether the operating parameter

limits were exceeded. 17

3. Determining the Normality of the

Data

To calculate the PM CEMS operating

parameter limit, the CEMS recordings 18

must be averaged over an appropriate

averaging period. (See the discussion in

the following section.) Accordingly,

sources would be required to identify

the mathematical model that best fits

the screened CEMS data for purposes of

averaging the data. For example, a logor exponential fit may better represent

a ‘‘normal’’ fit relative to an arithmetic

model. To identify which mathematical

model represents the best fit, facilities

would calculate the Shapiro-Wilk

Normality test statistic (W) at the 95%

confidence level using the data obtained

from the PM CEMS 19. The mathematical

model with a Shapiro-Wilk test statistic

closest to one (1) would be the model

used for averaging at the facility. This

mathematical model would be used for

all PM CEMS emissions averaging at the

facility.

4. Averaging Periods for the PM CEMS

Operating Parameter Limit

Fundamental to any emissions control

parameter is the way averaging affects

an emissions standard or limit. At a

fixed numerical value, a standard or

limit is more stringent as the averaging

period decreases and less stringent as

the averaging period increases because

of emissions variability. In the proposed

rule, EPA said that an appropriate

averaging period for PM CEMS would

be the length of time it takes to make

three Method 5 runs. The Agency still

believes this is an appropriate point of

departure for the averaging period for

the PM CEMS operating parameter limit.

We proposed a 2 hour averaging

period for PM CEMS, reasoning that it

would take 40 minutes to accumulate

enough PM sample to meet Method 5

requirements for sample ‘‘catch.’’ See 61

FR at 17379. Commenters argued,

however, that although it takes 40

minutes to accumulate enough sample,

test crews routinely sample for one

hour. In addition, comments received in

response to CEMS NODA 1 said the

sampling time for a Method 5 run can

vary from 1 to 8 hours. Basing the

averaging period for the PM CEMS

operating parameter limit on the length

of time it takes to perform three Method

5 runs would result in an averaging

period in the range of 3 to 24 hours 20.

This is still being evaluated.

5. Options for Calculating the PM CEMS

Operating Parameter Limit

As discussed above, the stringency of

the standard is a function of two

variables—its numerical limit and the

averaging period. Equally stringent

standards would have a higher

numerical limit at shorter averaging

period and a lower numerical limit at a

longer averaging period. Thus, to

calculate the PM CEMS operating

parameter limit, one of these two

variables must be held constant—either

the numerical limit or the averaging

period. This section discusses two

options for calculating an achievable

PM CEMS operating parameter limit by

defining the averaging period. EPA

investigated ways to define the

numerical limit and allow facilities to

calculate the averaging period

associated with that numerical limit, but

found these alternatives often resulted

in trial-and-error type calculations and

might result in all facilities having

different limits and averaging periods.

We believe these alternatives are too

labor intensive and confusing—both for

facilities and the enforcement

authority—and rejected this approach.

Based on comments and further

analysis, the Agency will prescribe one

methodology in the final rule.

a. Using Rank Statistics to Calculate

the PM CEMS-based Operating

Parameter Limit at One, Fixed

Averaging Period. Under this approach,

the Agency would establish an

averaging period common to all sources

and each source would calculate its PM

CEMS operating parameter limit using

rank statistics. (As discussed above,

EPA is considering selecting an

averaging period from within the range

of three to 24 hours.) The averaging

period would be the same for all

facilities but the numerical value of the

PM CEMS operating parameter limit

would differ from facility-to-facility

based on the historical data obtained at

each facility.
67798 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

21For simplicity, we believe it is best for facilities

to ignore periods when the CEMS recorded data

which was screened out and calculate the rolling

averages as if the remaining data occurred

sequentially. EPA specifically requests comment on

this approach.

22For example, some PM control devices are so

over-designed that it is difficult to force them to

operate at elevated PM levels for the duration of a

performance test.

Using the rank statistics option to

calculate the limit would involve the

following steps. First, the facility would

take the screened PM CEMS data (i.e.,

after non-compliance data has been

removed) and calculate rolling averages

sequentially from the Compliance

Date 21 using the best-fit mathematical

model and the averaging period EPA

promulgates. The facility would then

take the resulting rolling averages and

sort them in order from lowest to

highest. The facility’s PM CEMS

operating parameter limit would be the

95th percentile highest PM CEMS

rolling average, by rank, experienced

during the period the PM CEMS data

was accumulated. The 95th percentile is

proposed here because it is the

percentile level EPA historically uses

for these types of calculations. EPA

could promulgate some other percentile

level, the 90th or 99th for example, if

another percentile level is achievable

and better represents good PM control.

This rank statistics option is easier to

implement, relative to the other options.

It also would result in a PM CEMS

operating parameter limit that is in the

range of actual emissions experienced

by the facility (i.e., as opposed to

statistically projected emissions) and

demonstrated by the facility to be

achievable over time. Since the limit for

all sources would be based on an

averaging period that would be fixed in

the rulemaking, the limit would be

easier to enforce as well.

b. The Traditional Standard Setting

Approach. Another approach the

Agency is considering to determine the

PM CEMS operating parameter limit is

to use the way EPA has established

CEMS-based standards in the past. This

approach involves calculating the

average and standard deviation of the

data set and projecting an emissions

level associated with the data. As

discussed in the MWC rule, EPA

calculated ‘‘continuous compliance

levels’’ for each source using the

equation, below.

where: y=x ̃+K*5

y = the continuous compliance level;

‘‘x-bar’’ = the sample average

k = a constant associated with the

averaging period and one exceedance

per year; and

s = the sample standard deviation.

This option has some benefits and

weaknesses. As discussed, it reflects a

procedure EPA has previously used to

establish CEMS-based standards. It

would also result in every facility

having the same averaging period and

thus making it easier to track and

enforce. However, more complicated

statistics are involved. EPA also

compares emissions from more than one

facility when it uses this approach to set

standards and would be unable to

oversee the application of this approach

on a site-specific basis. As a result, this

approach may be unworkable as a way

to establish a PM CEMS operating

parameter limit.

6. Consideration of a Variance

Procedure to Project a Higher PM CEMS

Operating Parameter Limit

As discussed previously in today’s

notice, the PM CEMS operating

parameter limit would be based on

CEMS recordings during the nine

months after the Compliance Date

during those periods of time that the

source was operating within the

operating parameter limits established

during the performance test (i.e., the

operating parameter limits established

in the Certification of Compliance

(CoC)). Comments received in response

to the proposed rule questioned the

need to establish PM-related operating

parameters based on the performance

test if: (1) PM emissions measured using

manual methods during the

performance test were well below the

PM MACT standard; and (2) emissions

of HAPs (i.e., SVM, LVM, and possibly

Hg, and D/F) for which PM would be

used as an operating parameter limit

were well below their MACT standards.

Commenters were concerned that,

although their sources may readily

achieve the MACT PM standard, it may

be difficult 22 or expensive to ensure that

performance test PM levels are

representative of the full range of levels

achieved during operations. The same

situation could occur with the PM

CEMS operating parameter limit just

discussed. Infrequent exceedances of

the PM CEMS operating parameter limit

might or might not be an indication that

the SVM, LVM, Hg, D/F, or PM MACT

emission standards have been exceeded.

Accordingly, commenters recommended

that the rule allow sources to project

higher PM-related operating parameters

based on how much performance test

emissions for these HAPs were below

their MACT standards.

EPA agrees in theory that establishing

the PM CEMS operating parameter limit

considering performance test operations

(i.e., historical CEMS data when the

source operated within the CoC

operating parameter limits) could result

in an overly conservative operating

parameter for PM control at sources

with low PM and low HAPs that require

PM control to ensure compliance. To

address the concerns expressed in the

comments received on the proposed

rule, the Agency is considering a

variance procedure to establish an

higher projected PM CEMS operating

parameter limit.

The variance procedure would allow

facilities with very low concentrations

of PM and HAPs requiring PM control

for compliance to increase their PM

CEMS operating parameter limit

(derived from operations within the CoC

operating parameter limits). The factor

used to increase the PM CEMS operating

parameter limit could be defined as the

ratio of the MACT standards for which

PM control is required to assure

compliance, to the performance test

levels of those HAPs. To ensure that the

source is still be in compliance with the

MACT PM standard, the same ratio

would be calculated for the PM standard

to the unadjusted PM CEMS operating

parameter limit. This approach is based

on the principle that, at a facility which

has experienced no changes in facility

operations, the ratio of emissions of

HAPs which require PM control to

ensure compliance to the PM

concentration in the stack is either

constant or decreases as PM increases.

In addition, revised (i.e., less stringent)

traditional operating parameter limits

for the PM control devices

corresponding to the higher projected

PM CEMS operating parameter limit

could be established based on historical

operating data at levels near the higher

projected PM CEMS operating

parameter limit.

For illustration, an example follows.

Assume that a hazardous waste

incinerator has low metals in the feed

and uses a HEPA filter for PM control.

Further assume that: This incinerator’s

measured metals emissions during the

performance test were 10 μg/dscm and

7 μg/dscm for SVM and LVM,

respectively; that the PM concentration

measured during the performance test

was 5 μg/dscm; for simplicity that PM

control is not required to assure

compliance with the D/F and Hg

standards; the unadjusted PM CEMS

operating parameter limit is 15 mg/

dscm; and from the HWC NODA

published on May 2, 1997, that the

promulgated standards are 100 μg/dscm,

55 μg/dscm, and 34 mg/dscm for SVM,

LVM, and PM, respectively. The ratio of

the standard to the measured levels are

10 and 7.8 for SVM and LVM. For PM,
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67799

23The Agency is considering comments that

significant D/F may not be adsorbed on emitted PM

in all cases. Cement and lightweight kiln PM, in

particular, is generally process dust (i.e., raw

material) that has little affinity for absorbing D/F.

the ratio is 6.8. The unadjusted PM

CEMS operating parameter limit would

be increased by a factor of 6.8 since the

ratio calculated for PM has the lowest

numerical value.

a. HAPs for which PM control is

necessary to ensure compliance. PM

would be used as an operating

parameter limit for semivolatile metals

(SVM), low volatility metals (LVM), and

if activated carbon is used, dioxin and

furan (D/F) and mercury (Hg). See 61 FR

17422 and 17430 (April 19, 1996).

Although the Agency is reconsidering

whether PM is an appropriate operating

parameter to ensure compliance with

the D/F standard in some cases,23 PM

would be an appropriate operating

parameter if activated carbon injection

were used to control D/F or mercury.

This is because D/F and mercury adsorb

onto the activated carbon, and as PM

emissions increase, emissions of

activated carbon with adsorbed D/F and

mercury increase.

b. Projecting a higher PM CEMS

operating parameter limit considering

the ratio of the standard to the

measured level of a HAP. The variance

would be based on the principle that, as

PM emissions increase, the ratio of

emissions of each HAP for which PM is

an operating parameter limit (i.e., SVM,

LVM, and possibly D/F and Hg) to PM

emissions either is constant or

decreases. Thus, the PM CEMS

operating parameter limit derived from

operations within the CoC operating

parameter limits could be increased

without exceeding the MACT standards

for those HAPs by a factor considering

the ratio of the standard for each of

those HAPs to the performance test level

of each HAP.

LVM are generally not volatilized in

the combustion chamber and thus are

evenly distributed over all sizes of

particulates. Thus, as PM emissions

increase, the ratio of LVM emissions to

PM emissions will be constant.

SVM are generally volatilized during

combustion and condense preferentially

on small particulates prior to (or in) the

PM control device. Thus for many PM

control devices, as PM emissions

increase, the ratio of larger particulates

to smaller particulates increases, and

the ratio of SVM emissions to total

particulate emissions decreases (i.e.,

because the larger particulates have a

lower concentration of SVM). For

emission control trains where PM

particle size may remain constant with

an increase in PM emissions, the ratio

of SVM emissions to PM emissions

would remain constant.

D/F and Hg are adsorbed onto the

surface of carbonaceous particulates

(e.g., activated carbon). Smaller

particulates have a larger surface area

per mass of particulate than larger

particulates, and thus D/F and Hg

concentrations would be higher for

smaller particulates. Thus, similar to

SVM, as PM emissions increase and the

ratio of larger particulates to smaller

particulates increases, the ratio of D/F

and Hg emissions to total particulate

emissions should decrease (i.e., because

the larger particulates have a lower

concentration of D/F and Hg).

The PM CEMS operating parameter

limit derived from performance test

operations (i.e., calculated from

historical CEMS data when the source

operated within the regulations) could

be increased without exceeding

(theoretically) the MACT standards for

SVM, LVM, and possibly D/F and Hg by

the ratio of the standard for each of

those HAPs to the performance test level

of each HAP. It would be reasonably

conservative, however, to project the

higher PM operating parameter limit by

the ratio of some fraction of the standard

for those HAPs to the performance test

level of each HAP. This fraction of the

standard would need to allow for

adequate flexibility for sources with low

PM and HAPs for which PM control is

required while ensuring that the

standards are being met continuously. A

specific percentage of the standard

within the range of reasonable values—

50% to 100%— could be selected and

would be appropriate given the

uncertainty of projecting a PM operating

limit that is a primary compliance

measure for several MACT emissions

standards. EPA believes choosing 75%

of the standard as the basis for

calculating the ratio is a reasonable

balance of these issues. The percentage

that would be appropriate is a point of

interest for the Agency.

Given that the PM CEMS operating

parameter limit is a compliance measure

for SVM, LVM, and possibly D/F and Hg

the allowable higher projected PM

CEMS operating parameter limit would

be the lowest of the values projected for

each of these standards. For example, if

the projected PM CEMS operating

parameter limit based on the ratio of

75% of the SVM standard to the SVM

performance test level was lower than

the PM CEMS operating parameter limit

projections for LVM (and possibly D/F

and Hg), then the SVM-projected PM

CEMS operating parameter limit would

be used to ensure that the SVM standard

was not exceeded at the higher

projected PM operating parameter limit.

The Agency is concerned, however,

about increasing the PM CEMS

operating parameter limit itself by the

ratios discussed above. This is because

the limit would be established at the

upper end of the range of actual CEMS

readings, or perhaps at levels that

statistically exceed what would be

expected. See above discussion of

options for calculating the PM CEMS

operating parameter limit. It may be

more appropriate to project the higher

limit using the following options.

Under option 1, the ratio determined

above would be applied to the average

PM emissions over time determined by

the PM CEMS instead of applying the

ratio directly to the unadjusted PM

CEMS limit itself. The product of the

ratio and the average PM emissions

would then be subtracted from the

average emissions to determine the

correction to the PM CEMS operating

parameter limit. This correction would

then be added to the PM CEMS

operating parameter limit to determine

the revised PM CEMS operating

parameter limit. Using the example

described above and assuming average

PM CEMS emissions are 2 mg/dscm, the

lowest ratio (6.8 for PM) would be

multiplied by the average PM emissions

(2x6.8 = 13.6) and the average emissions

would be subtracted from this product

(13.6–2). This difference (11.6) would be

added to the PM CEMS operating

parameter limit to obtain the revised PM

CEMS operating parameter limit.

Under option 2, the PM CEMS

recordings during the performance test

would be analyzed to calculate a PM

CEMS operating parameter limit and

that limit would be increased by the

factor defined by the ratio discussed

above (e.g., 6.8 in the first example).

This approach would ensure that

infrequent high PM episodes that

occurred over months of CEMS

operations would not be driving a PM

CEMS limit that was then projected

further upward using the factors

discussed above (unless those high PM

episodes actually occurred during the

performance test). Given the truncated

emissions database (i.e., the

performance test) for calculating the

higher projected limit under this option,

however, the limit may in fact be lower

than the limit normally calculated from

the full CEMS emissions database (i.e.,

without attempted to project a higher

limit). In this case, the limit which is

numerically higher would be used.

The Agency requests information on

which approach would be more

appropriate for projecting a higher PM

CEMS operating parameter limit.

c. Ensuring that the higher projected

PM CEMS operating parameter limit
67800 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

24A source would be allowed to operate

infrequently at levels approaching a higher,

projected PM CEMS operating parameter limit that

is beyond the calibration curve. If, however, a

source operates for prolonged periods at levels

above the calibration curve, it must perform Method

5 tests at those higher concentrations and include

those higher PM levels in the POM CEMS

calibration. See discussion on extrapolating PM

CEMS calibration data elsewhere in today’s notice.

does not exceed the MACT PM

standard. The PM CEMS operating

parameter limit would also be used to

ensure compliance with the MACT PM

standard. We reiterate that the PM

CEMS operating parameter limit is not

a measure of the emissions standard—

the emissions standard is defined in the

rule as being measured by using manual

methods—it is instead an operating

parameter limit used to ensure

compliance with the applicable

standards. As discussed in section 1,

above, it is likely that due to several

factors the PM CEMS operating

parameter would have a different

numerical value that the MACT PM

standard.

One reason for different numerical

values is the use of different techniques

(i.e., one is manual methods based

while the other is CEMS-based) to

determine a PM emissions value. The

use of a manual method test to

determine a value is only a limited-time

(e.g., 3 to 24 hours every five years)

measure of emissions, whereas a CEMS

is a continuous measure of emissions

(e.g., ∼1 minute readings all the time).

Although the manual method will likely

be a measure of ‘‘high-end’’ PM

emissions during performance testing, it

may not account for all potential

variability during normal operations.

The use of a CEMS to monitor PM

emissions is a way to continuously

measure the variability of (both low and

high) PM emissions, inherent in any

engineered system.

Additionally, different values may be

a result of the different averaging

periods stated for manual methodsbased PM standard and the PM CEMS

operating parameter limit. See section 4,

above, for a discussion of the

interrelationship between a numerical

value of a limit or standard and the

averaging period. Having a PM CEMS

operating parameter limit with a

different, possibly higher, numerical

limit is permissible and does not negate

the value of the PM CEMS operating

parameter, provided there is reasonable

correlation between the operating

parameter and the MACT PM standard.

This section explains how EPA would

ensure that the numerically larger,

revised PM CEMS operating parameter

limit would not violate the national PM

standard.

Ensuring that the higher projected PM

CEMS operating parameter limit does

not exceed the MACT PM standard is

complicated by the fact that the PM

operating parameter limit would be

CEMS-based while the MACT PM

standard would be manual methodbased. Nonetheless, compliance with

the MACT PM standard can be ensured

by limiting the increase in the PM

CEMS operating parameter limit (i.e.,

the projected PM CEMS operating

parameter limit divided by the limit

prior to projection) to the ratio of the

MACT PM standard to the performance

test PM level on a manual method basis.

Given that projections rather than

measured values would be used to

ensure compliance with a standard, it

may be prudent to limit the increase in

the projected PM CEMS operating

parameter limit to the ratio of 75% of

the MACT PM standard to the

performance test PM level. A

conservative factor of 75% is within the

range of reasonable values the Agency

could have selected—50% to 100%.

Regarding the specific percentage EPA

chooses, the reader is referred to the

previous discussion regarding the

percentage EPA chooses for the HAP

standards that require PM control to

ensure compliance.

Using the example from above and

making the same assumptions, the ratios

would be calculated using 75 μ/dscm,

41μ/dscm, and 26 mg/dscm in the

numerator for SVM, LVM, and PM.

These values are 75% of the standards

for incinerators EPA discussed in the

May 2, 1997, HWC NODA. The resulting

rations would be 7.5, 5.9, and 5.1. Since

the ratio calculated for PM is the lowest,

ratio used to determine the revised PM

CEMS operating parameter limit would

be 5.1.

d. Establishing Revised Operating

Parameter Limits for the PM Control

Device Corresponding to the Higher

Projected PM CEMS Operating

Parameter Limit. Ideally, PM control

device operating parameter limits (e.g,

pressure drop across a fabric filter)

should be established to ensure

compliance with the higher projected

PM CEMS operating parameter limit for

compliance purposes while the CEMS is

malfunctioning. Absent these revised

(i.e., less stringent) operating parameter

limits, the source would be required to:

(1) Comply with the more stringent

operating parameter limits established

during the performance test that

correspond to the original PM CEMS

operating parameter limit; or (2) ensure

that a back-up CEMS is always

available.

The Agency is considering an

approach to establish revised operating

parameter limits for the PM control

device corresponding to operations at

the higher projected PM CEMS

operating parameter limit. Under this

approach, the source would analyze the

historical operating parameter values

during those periods of time that PM

emissions were close to the higher

projected PM CEMS operating

parameter limit. Issues that must be

addressed, include: (1) What range of

PM CEMS operating parameter limit

values should be considered to develop

the database for PM control device

operating parameter values; and (2) how

should the database be analyzed to

identify appropriate limits.

It may be appropriate to establish the

revised PM control device operating

parameter limits based on the 90th

percentile of values that occur when PM

levels are within 75% of the higher

projected PM CEMS operating

parameter limit. This would help ensure

that a significant data set was available

for evaluation and that the limits were

not based on the most lenient values

recorded. This is important because the

higher projected PM CEMS operating

parameter limit is likely to be well

beyond the calibration curve. 24

Based on further analysis, the Agency

may consider other approaches to define

an appropriate data set of PM control

device operating limits and identify

appropriate limits (e.g., considering a

different percentage of the historical

data and/or basing the limit on a

different percentile of data).

Alternatively, the Agency may conclude

that these approaches to revise the

performance test-based operating

parameter limits would be too

complicated or difficult for regulatory

officials to oversee, or that it would be

difficult to confirm compliance with the

standards. In this event, sources would

be required to continue to comply with

the PM control device operating

parameter limits established during the

performance test when the CEMS

malfunctions even though the PM CEMS

operating parameter limit has been

projected upward under procedures

discussed above.

e. Implementing the Variance.

Sources requesting the variance to

project a higher PM CEMS operating

parameter limit would include the

request with the Certification of PM

CEMS Performance (CoP) that would be

submitted within 12 months after the

Compliance Date. The variance request

must include documentation of the

analyses described above to identify the

higher projected PM CEMS operating

parameter limit and the revised, PM

control device operating parameters

associated with the higher projected PM
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67801

25 In fact as method accuracy improved, the PM

CEMS calibration statistics got better over time.

Extrapolating this data would lead to erroneous

conclusion that no retesting is ever needed, since

the PM CEMS calibration keeps getting better.

26 In this context, M5 is meant to refer to all the

methods (Method 5, Method 5A, . . ., Method 5I)

used to calibrate PM CEMS.

operating parameter limit. Sources

would be allowed to comply with the

higher projected PM CEMS operating

parameter limit immediately upon

submitting the CoP. Regulatory officials

would have three months to review the

variance request, however, and to notify

the source of intent to disapprove the

higher projected PM CEMS operating

parameter limit (or the associated

revised PM control device operating

parameter limits for use during CEMS

malfunctions). In such cases, the

regulatory officials would provide the

basis of their initial decision and

provide the source with an opportunity

to present, within 30 calendar days,

additional information before final

action on the variance.

7. EPA’s PM CEMS Testing Program to

Identify a CEMS-Based Emission Level

Achievable by MACT-Controlled

Sources

The Agency is undertaking an

additional PM CEMS testing program to

identify CEMS-based emission levels

that are achievable by hazardous waste

combustors (i.e., hazardous waste

burning incinerators, cement kilns, and

lightweight aggregate kilns) using

MACT control. The testing is scheduled

to begin in December 1997 and results

should be analyzed by December 1998.

The Agency is working with

representatives of the regulated

community to identify one source in

each of the three source categories that

is using MACT control and that would

be likely to define the most achievable

level (i.e., considering average PM

emissions and emissions variability) for

MACT-controlled sources.

Although these test results will not be

used as part of the final rule, the data

will be valuable to permitting

authorities and the regulated

community as a PM CEMS emission

benchmark that is achievable using

MACT controls. Permitting authorities

could use the data to identify sources

that appear to have established an

anomalously high CEMS-based PM

operating parameter limit, and as a

framework within which to review

Certifications of Performance in a costeffective manner. Likewise, sources

wanting to ensure that their facility is

operating in a manner representative of

MACT control could use this

information to see if their CEMS-based

PM operating parameter limits are

below the levels that MACT sources

show are achievable using MACT

control.

C. RCA Test Frequency

In the proposed rule, EPA said that

facilities would be required to perform

relative calibration audits (RCAs) on

their PM CEMS every 18 months. This

testing interval would be relaxed to 30

months for small on-site incinerators.

These time intervals coincided with the

proposed Performance Test intervals. If

these tests can be performed at the same

time as the performance tests, cost

savings can be realized by the facility

relative to what the costs would be if the

tests were not conducted at the same

time. As a result of the analysis of

comments on the performance test

frequency, the Agency is considering

requiring all facilities to conduct

comprehensive performance tests every

five (5) years. Therefore, we prefer that

RCA tests be performed every five years.

One of the goals of the PM CEMS

Demonstration Test program was to

quantitatively define what RCA

frequency is appropriate for PM CEMS.

Unfortunately, variability in the manual

method masks any error that can be

identified as being caused by drift in the

PM CEMS over time. Therefore, we are

unable to use the PM CEMS data from

the demonstration tests to extrapolate to

an appropriate re-test frequency 25.

Lacking these long-term data, it is

important to look at what is done in

other countries to qualitatively

determine this RCA test frequency. The

United Kingdom (UK) requires that

retesting be conducted at least every

year, and in Germany testing is required

every 3 to 5 years. The RCA test

frequency could therefore reasonably be

between one and five years. The UK,

though, heavily relies on manual

methods testing—so much so that they

believe using gas bottles is cost

prohibitive for gaseous (e.g., NOx and

SOx) CEMS testing and rely on manual

methods testing instead. EPA is inclined

to believe that the German’s longer

retest frequency is more consistent with

our regulatory framework.

D. Extrapolating PM CEMS Calibration

Data

One-minute or batch PM CEMS

readings during the course of operations

are likely to occasionally exceed the

highest M5i calibration point during the

course of PM CEMS use. This is because

the manual method results used to

derive the calibration are (nominally)

one hour block averages of emissions

over the sampling period while the PM

CEMS readings are averages of

emissions on the order of minutes. See

section 4, above, regarding the

interrelationship the numerical limits of

a standard or limit and its associated

averaging period. In addition, emissions

variability within the sampling period

of M5 is not likely to represent the full

range of emissions variability over all

periods of PM CEMS operation.

Therefore, a system is needed to allow

the extrapolation of data beyond the

calibration curve.

The revised calibration and

implementation scheme described in

today’s notice (i.e., multiple calibrations

(for light-scattering PM CEMS) over the

full range of emissions at the facility)

will result in a calibration from which

some reasonable and limited

extrapolation is reasonable. Therefore,

the Agency proposes to allow the

calibration curve to be used for

measurements up to 25% more than the

maximum M5 26 measurement observed

during the calibration. (This will be

referred to as the ‘‘125% point.’’)

Beyond this point (125% of the highest

M5 measurement) EPA is concerned

that extrapolating the calibration data

might lead to false compliance

determinations. Therefore, some

environmentally conservative approach

must be employed.

Note that the ability to extrapolate

beyond the calibration curve in no way

would mitigate the facility’s

requirement to calibrate over its full

range of PM emissions. If a facility

experiences continuous periods of PM

emissions beyond the calibration curve,

it would be obligated to perform tests to

capture these data into the calibration

curve. For example, a facility may

determine that it occasionally has

several continuous hours of PM CEMS

readings which are greater than the

125% point. Several continuous hours

are enough time to conduct a M5 test,

so the facility would be obligated to

conduct M5 tests at this emissions level

and include these data in the calibration

curve used at the facility. EPA requests

comment on how long a period of

sustained operations at emissions levels

greater than the 125% point would be

necessary to require these additional

calibration data points.

1. Extrapolating Light-Scattering PM

CEMS Calibration Data

If it is necessary to extrapolate beyond

the 125% point, an environmentally

conservative approach would consist of

determining the slope of the calibration

curve at the 125% point and have the

calibration continue with a slope equal

to or greater than the slope of the curve

at the 125% point. For example if the
67802 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

27Note: If the slope of the quadratic fit is ever less

than zero for values of PM CEMS output above what

was measured by the manual method (that is, it ever

has a negative slope), this indicates that the

correlation between M5 measurements and PM

CEMS output is not represented by a quadratic fit

and that another mathematical model should be

used.

curve is a log-normal relation, the slope

of the curve at the 125% point would be

positive, but less than the slope of a

straight line that would also describe

the correlation between method results

and PM CEMS outputs. Therefore, if a

log-normal relationship best describes

the calibration curve, facilities should

extrapolate beyond the 125% point

using a straight line beyond the 125%

point. The slope of the straight line

would be the slope of the log-normal

curve, taken from the points on the

calibration curve associated with the

lowest M5 measurement and the 125%

point.

If the calibration curve is best

described by a straight line arithmetic

fit, then extrapolating beyond this 125%

point would depend on the slope of any

quadratic fit of the data. If the quadratic

curve slopes negative at higher values of

PM CEMS outputs, then the straight line

defined by the calibration would be

used to extrapolate beyond the 125%

point. If the quadratic fit slopes positive

at higher values of PM CEMS outputs,

then the quadratic fit would be used

beyond the 125% point.

Finally, if the calibration curve is a

quadratic fit, then the quadratic fit can

be used to extrapolate all data 27.

2. Extrapolation of Beta-gage Calibration

Data

For Beta-gage PM CEMS,

extrapolating beyond the 125% point

would involve continuing the straight

line defined by its linear calibration

equation. Beta-gage PM CEMS

apparently are not sensitive to particle

changes in the physical characteristics

of particulate, as the light-scattering PM

CEMS are. Therefore, a straight-line fit

best represents the calibration for betagage PM CEMS at all times.

E. Need to Calibrate to Twice the

Emissions Standard

One issue raised by commenters

during the comment period for the

proposed rule was EPA’s proposal that

facilities calibrate the PM CEMS to

twice the emissions limit. Commenters

raised concerns that facilities might not

be able to emit PM at a concentration

equal to twice the standard. They also

said this aspect of the proposal in

essence asks facilities to violate the

emission standard and could lead to an

enforcement action against the facility.

Commenters also had concerns that

facility personnel may not be

sufficiently familiar with the various

process and APCD factors to acceptably

calibrate the PM CEMS over the full

range of operations experienced at the

facility. Each of these points are

discussed in the following paragraphs.

EPA agrees that it would be difficult

for many facilities to emit PM at any

prescribed level. Many facilities have

redundancies in their PM APCDs to

such an extent that emitting to the

emissions limit may be problematic.

However to have accurate PM CEMS

measurements, facilities need to

calibrate the PM CEMS over the full

range of emissions experienced at the

facility. As a result, it would be

necessary to require facilities to

calibrate the PM CEMS over the full

range of operations, including PM

emissions. This would eliminate the

prescriptive nature of how high the

calibration needs to be while still

addressing the issue that the sitespecific calibration of PM CEMS covers

the broad range of PM emissions

experienced at the facility.

EPA does not agree, however, that this

approach could cause facilities to

violate the manual method MACT PM

standard. The PM standard would be

defined as the average of three manual

method measurements. Any single run

above the standard would not be a

violation by itself. Average emissions

over the calibration would be below the

standard for a source equipped with

MACT controls. Therefore, we expect

that sources would be able to calibrate

PM CEMS at levels higher than the PM

emissions standard and still remain in

compliance with the standard. If this is

not practical, however, EPA may

consider a waiver of the manual method

PM standard during periods of

calibrating (and performing RCA tests

of) the PM CEMS. The need to obtain

and audit an accurate calibration at and

above the PM standard may override

any concerns about high short-term PM

emissions. EPA would want to limit the

frequency and duration of calibration

runs that exceed the standard, however.

We request comment regarding how

such limits could be implemented. One

way this could occur is to require that

sources request in the performance test

plan approval to exceed the standard

during calibration. Approval to exceed

the standard would only be required if

the average of all PM CEMS calibration

runs is greater than the PM standard.

The revised draft PS 11 states that

different PM levels should be obtained

by varying process conditions or,

alternatively, by adjusting the APC

system. It is relatively silent in

presenting a well-defined protocol with

guidelines on how EPA expects

calibration tests to be performed. This is

because individual sources should

know best how to vary their PM

emissions. For instance, inserting a

throttle plate in lieu of one (or several)

bags in a baghouse and varying the

opening of the throttle plate(s) is likely

an effective way to vary PM

concentration for the calibration at a

facility equipped with a baghouse.

Varying power to an ESP and simulating

various failure modes (such as lowering

the temperature in the ESP to cause

condensation on the plates) is likely

vary PM sufficiently for the calibration

at sources equipped with an ESP.

The experience gained during the PM

CEMS Demonstration tests suggests that

one can obtain a suitable range of

emissions by varying process conditions

that affect inlet PM loading to the last

in a series of PM APCDs and adjusting

the performance of that last APCD.

Exactly how this is accomplished at a

given facility will vary and depend on

the waste fed to the unit, how the

facility is designed and operated, and in

what order the APCDs are configured.

Therefore, the language in the revised

PS11 is adequate. More prescriptive

language may not work in most cases.

Finally, EPA, will be working with

industry representatives to develop

approaches to better describe how

calibration tests should be performed at

individual HWC facilities. EPA expects

to provide this information in a

technical implementation guide.

F. Allowing PM CEMS to be Used In-lieu

of Method 5 Tests

Although the PM CEMS would be

required only as an operating parameter,

EPA intends to allow facilities to

voluntarily elect to use the PM CEMS

for compliance with manual methodsbased PM standards. Using the PM

CEMS for compliance is expected to

provide a cost savings to the facility

since the facility would not have to

conduct periodic Method 5 tests to

document compliance with PM

standards. Instead a facility could elect

to use the PM CEMS measurements

during these periodic tests. This would

be acceptable if the facility uses the

block average of the PM CEMS readings

during the M29 tests for the SVM and

LVM standards as the particulate

‘‘method result.’’

G. Waivers from the PM CEMS

Requirements

In the proposed rule, EPA requested

comment on waiving the PM and Hg

CEMS requirement for small, on-site

incinerators. See 61 FR at 17439. Upon
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67803

further consideration, EPA has

identified other classes of incinerators

where a PM CEMS requirement may be

impractical. If the PM CEMS

requirement is waived for a given

source, the facility would have to

comply with operating parameter limits

to assure compliance for PM. Of course,

a facility could always elect to use a PM

CEMS for compliance even if a waiver

procedure is promulgated for that

facility.

1. Waiver of PM and Hg CEMS

Requirements for Small On-site

Incinerators

EPA is considering whether to waive

the PM and Hg CEMS requirements for

small, on-site incinerators (SOSI). See

the proposed rule, 61 FR at 17439. If a

waiver is promulgated, a SOSI would be

required to use existing operating

parameters in lieu of a PM CEMS to

document compliance with the PM,

SVM, and LVM standards.

2. PM CEMS Waiver for Sources With

Short Life-Spans

Given the PM CEMS compliance

schedule discussed in section IV.A,

above, facilities with short, fixed lifespans raise several issues. For instance,

certain government-run incinerators are

constructed for the purposes of

destroying waste that is too hazardous

to transport off-site. These incinerators

often have short life spans (ranging from

months to a few years) and are

constructed to fulfill the requirements of

a consent decree, memorandum of

understanding (MOU), or other legally

binding enforcement agreement. For

example the Department of Defense

(DoD), acting under a MOU with EPA,

may construct an incinerator to destroy

nerve-gas agents that are too hazardous

to transport. When this activity is

complete, the MOU would obligate DoD

to dismantle and destroy the

incinerator.

It does not seem practical to mandate

that these facilities use PM CEMS if they

will be in service for less than, or

slightly longer than, the implementation

schedule just discussed. Therefore, EPA

is considering a waiver of the PM CEMS

requirement for HWCs operating under

a legally binding agreement that ensures

the source will stop burning hazardous

waste within three years of the

Compliance Date.

EPA could likewise grant a waiver

from the PM CEMS requirement for

facilities with short life-spans that lack

the legally binding agreement discussed

above. However, EPA is concerned that

without a legally binding agreement to

cease operations, the Agency lacks

certainty that operations will cease by a

prescribed date. For this reason, EPA

would consider a waiver for other

facilities that plan to cease operations

within the first year of compliance with

the HWC regulations, that is, prior to the

need to use PM CEMS as the operating

parameter for PM control. Facilities that

operate after the first year would need

to have PM CEMS installed, calibrated,

meet data availability requirements,

determine the PM CEMS operating

parameter limit, and use the PM CEMS

as the primary operating parameter for

PM control.

3. Other Sources

As discussed in section III.C. of this

NODA, EPA may be unable to determine

whether the results of the PM CEMS

demonstration test can be transferred to

two classes of incinerators: Those with

waste heat boilers and mobile

incinerators. See section III.C. for more

information.

V. Other Issues Concerning CEMS and

Test Methods for HWCs

A. Performance Specifications for

Optional CEMS

In the proposed rule, EPA proposed

other performance specifications for

multi-metals, hydrochloric acid (HCl),

and chlorine gas (Cl2) CEMS. These

performance specifications were

proposed as PS10, 13, and 14,

respectively. Based on what EPA has

learned during the course of

demonstrating PM and Hg CEMS, EPA

expects not to promulgate the draft

performance specifications (PS) for

these CEMS at the time of the HWC final

rule. As discussed in section II of

today’s notice, EPA does not plan to

promulgate a PS for total mercury (Hg)

CEMS either. The Agency has not tested

MM and Cl2 CEMS to determine what

performance is achievable by the CEMS.

Hg CEMS have not been demonstrated

as a compliance tool for universal

application to all HWCs. EPA has tested

HCl CEMS in preparation for the

medical waste incinerator rulemaking

but did not require the use of HCl CEMS

in that rulemaking (see discussion

starting at 62 FR 48360, September 15,

1997) and does not believe requiring

HCl CEMS for the HWC rulemaking is

appropriate either (see 61 FR at 17433).

Instead, EPA will consider enabling

sources to demonstrate these CEMS on

a site-specific basis and to develop

performance levels for the CEMS as part

of the demonstration. The Agency’s only

concern is that the CEMS be proven to

be a better and more reliable indicator

of compliance for the HAP or standard

than the requirements specified in the

regulations. This approach is now being

used to demonstrate a multi-metals

CEMS at the Von Roll incinerator in

East Liverpool, Ohio.

EPA intends to accumulate the CEMS

demonstration results and experience

and will share that information with

permitting authorities and sources

wishing to document compliance with

CEMS. Since the HCl CEMS have been

demonstrated by EPA, we believe the

HCl CEMS performance specification

could more easily be used as a point of

departure for implementing HCl CEMS

at a given facility.

B. Stack Sampling Test Methods

Another question is whether EPA

should simplify the task of determining

the appropriate manual method tests to

be used for compliance. Currently, stack

sampling and analysis methods for

HWCs are (with a few exceptions)

located in RCRA’s SW–846 for

compliance with the BIF and incinerator

rules, and in 40 CFR part 60, Appendix

A for compliance with the NSPS and

other air rules. Facilities could be

required to perform two identical tests,

one for compliance with MACT or

RCRA and one for compliance with

other air rules, using identical test

methods simply because one method is

an ‘‘SW–846’’ method and the other an

‘‘air method.’’

Stack test methods HWCs use for

compliance should be found in one

place to facilitate compliance. EPA

intends to reference 40 CFR part 60,

Appendix A, when it requires a specific

stack-sampling test method. A few SW–

846 methods do not have equivalents in

40 CFR part 60, Appendix A, namely

the VOST and semi-VOST methods. In

these few cases, EPA would continue to

refer to these SW–846 methods as well.

This discussion only affects stack

sampling methods and has no affect on

feedstream sampling and analysis.

Dated: December 19, 1997.

Matt Hale,

Acting Director, Office of Solid Waste.

Appendix I—Method 5i

Method 5I—Determination of Low Level

Particulate Matter Emissions From Stationary

Sources

1. Applicability and Principal

1.1 Applicability. This method applies to

the determination of low level particulate

matter (PM) emissions from stationary

sources and facilities performing calibrations

or calibration audits of particulate matter

continuous emission monitors as specified in

the regulations. The method is effective for

total train catches of 50 mg or less. The

minimum detection limit for this method can

be determined by repeatedly collecting and

analyzing blank samples. A blank sample is

a sample of blank air collected and analyzed
67804 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

in the normal manner. The limit of detection

can be calculated by collecting and analyzing

seven blank samples and then calculating an

estimate of the sample standard deviation of

these blanks. The limit of detection would be

three times the estimated sample standard

deviation.

1.2 Principal. The PM is withdrawn

isokinetically from the source and collected

on a 47 mm glass fiber filter maintained at

a temperature of 120° ±14°C (248° ±25°F).

The PM mass, which includes any material

that condenses at or above the filtration

temperature, is determined gravimetrically

after the removal of uncombined water.

2. Apparatus

2.1 Sampling Train. The sampling train

configuration is the same as shown in

Method 5, Figure 5–1. The sampling train

consists of the following components: Pitot

Tube, Probe liner Differential Pressure Gauge,

Filter Heating System, Condenser, Metering

System, Barometer, and Gas Density

Determination Equipment. Same as Method

5, Sections 2.1.2 to 2.1.4, 2.1.6 and 2.1.7 to

2.1.10, respectively.

2.1.1 Probe Nozzle. Same as Method 5,

Sections 2.1.1 with the exception that it is

constructed of Borosilicate or quartz glass

tubing with sharp, tapered leading edge.

2.1.2 Filter Holder. The filter holder for

this sampling train is constructed of

Borosilicate or quartz glass front cover

designed to hold a 47 mm glass fiber filter,

with a stainless steel filter support, a silicone

rubber or Viton O-ring and Teflon tape seal.

The holder design will provide a positive

seal against leakage from the outside or

around the filter. The filter holder assembly

fits into a stainless steel filter holder and

attaches immediately at the outlet of the

probe (or cyclone, if used). The tare weight

of the filter, Borosilicate or quartz glass,

stainless steel filter support, silicone rubber

or Viton O-ring and Teflon tape seal will not

exceed 31 grams. The filter holder is

designed to use a 47 mm glass fiber filter

meeting the criteria in section 3.1.1 of

Method 5. Figure 5I–1 presents a schematic

of the filter holder system. These units are

commercially available.

2.1.3 Glass Plugs and Clamps. Once the

filter holder has been assembled, desiccated

and tared it is critical that the filter be

isolated from any external sources of

contamination. This can be accomplished by

covering the leak-free ground glass or O-ring

socket on the front half glass filter cover with

a Borosilicate or quartz ground glass plug.

The plug shall be secured in place with the

appropriate sized laboratory impinger clamp

or any system that can ensure a leak-free

fitting. It is beneficial to place the glass plug

on the inlet socket as soon as the unit is

assembled, however do not tare the assembly

with the plug in place, as this will increase

the tare weight introducing additional error

into the final weighings.

2.2 Sample Recovery. Is the same as

Method 5 for: Glass Sample Storage

Containers, Graduated Cylinder and/or

Balance, Plastic Storage Containers, Funnel

and Rubber Policeman (Method 5 sections

2.2.3, 2.2.5—2.2.8, respectively) with the

following exceptions:

2.2.1 Probe-Liner and Probe-Nozzle

Brushes. Teflon and nylon bristle brushes

with stainless steel wire handles, should be

used to clean the probe. The probe brush

shall have extensions (at least as long as the

probe) of Nylon, Teflon, or similarly inert

material. The brushes shall be properly sized

and shaped to brush out the probe liner and

nozzle.

2.2.2 Wash Bottles—Two. Teflon wash

bottles are recommended however,

polyethylene wash bottles may be used at the

option of the tester. It is recommended that

acetone not be stored in polyethylene bottles

for longer than a month.

2.2.3 Sample Holder: A portable carrying

case with clean compartments of sufficient

size to accommodate each filter assembly.

The filters shall be able to lay flat with the

stainless steel filter support placed down in

the compartment. This system should have

an air tight seal to prevent contamination to

the filters during transport to and from the

field. It is recommended that desiccant be

used in this case. The desiccant, if used, is

housed in a container that is capped with a

0.1 micron screen to ensure that no dust

particles can contaminate the outside of the

filter housings during transport.

2.3 Analysis. The same as Method 5 for

sections 2.3.2–2.3.7 with the following

exception:

2.3.1 Teflon Liner: Teflon liners are

used for the analysis of the probe and nozzle

particulate catch. The liners are washed with

soap (Alconox or similar low residue

laboratory soap) and water. Each liner is then

rinsed with DI Water followed by an acetone

(low residue) rinse. The static charge on the

liners is removed using an anti-static rinse

and then the liners are oven dried and

desiccated.

3. Reagents

3.1 Sampling. The reagents used in

sampling are the same as Method 5 for: Silica

Gel, Water, Crushed Ice, Sample Recovery

Reagents, and Desiccant (sections 3.1.2–3.1.5,

3.2–3.3.2) with the following exceptions:

3.1.1 Filters. 47 mm Glass fiber filters,

without organic binder, exhibiting at least

99.95 percent efficiency (<0.05 percent

penetration) on 0.3-micron dioctyl phthalate

smoke particles. The filter efficiency test

shall be conducted in accordance with ASTM

Standard Method D2986–71 (Reapproved

1978) (incorporated by reference—see

§ 60.17). Test data from the supplier’s quality

control program are sufficient for this

purpose. In sources containing SO2 or SO3,

the filter material must be of a type that is

unreactive to SO2 or SO3. Citation 10 in the

Bibliography for Method 5, may be used to

select the appropriate filter.

3.1.2 Stopcock Grease. Stopcock grease

cannot be used with this sampling train. It is

recommended that the sampling train be

configured with glass joints, using o-ring

seals or screw-on connectors with Teflon

sleeves, or similar.

3.1.3 Acetone. Pesticide grade or

equivalent low residue type Acetone is used

for the recovery of particulate matter from the

probe and nozzle.

3.1.4 Latex Gloves. Disposable, powder

free, latex surgical gloves are used for all

handling of the filter housings at all times.

4. Procedure

4.1 Sampling. The complexity of this

method is such that, in order to obtain

reliable results, testers should be trained and

experienced with the test procedures. The

sampling procedures are the same as Method

5 for: Preliminary Determinations, LeakCheck Procedures, Particulate Train

Operation (sections 4.1.2, 4.1.4, 4.1.5

respectively ) with the following exceptions:

4.1.1 Pretest Preparation. Is the same as

Method 5, section 4.1.1 with the following

exception: Label filter supports prior to

loading filters into the holder assembly. This

can be accomplished with a diamond scribe.

As an alternative, label the shipping

container compartments (glass or plastic) and

keep the filter holder assemblies in these

compartments at all times except during

sampling and weighing. Using the powder

free latex surgical gloves (surgical gloves

must be used at all times when handling the

filter holder assemblies). Place the Viton Oring on the back of the filter housing in the

O-ring grove. Place a 47mm glass fiber filter

on the O-ring with the face down. Place a

stainless steel filter holder against the back

of the filter. Carefully wrap 1⁄4 inch wide

Teflon tape one time around the outside of

the filter holder overlapping the stainless

steel filter support by approximately 1⁄8 inch.

Gently brush the Teflon tape down on the

back of the stainless steel filter support.

Desiccate the filter holder assemblies at

20±5.6° C (68±10° F) and ambient pressure

for at least 24 hours and weigh at intervals

of at least 6 hours to a constant weight, i.e.,

0.5 mg change from previous weighing;

record results to the nearest 0.1 mg. During

each weighing the filter holder assemblies

must not be exposed to the laboratory

atmosphere for a period greater than 2

minutes and a relative humidity above 30

percent. Alternatively (unless otherwise

specified by the Administrator), the filters

holder assemblies may be oven dried at 105°

C (220° F) for 2 to 3 hours, desiccated for 2

hours, and weighed.

4.1.2 Same as Method 5, section 4.1.2.

4.1.3 Preparation of Collection Train. Is

the same as Method 5, section 4.1.3 with the

following exception: During preparation and

assembly of the sampling train, keep all

openings where contamination can occur

covered until just prior to assembly or until

sampling is about to begin. Using clean

disposable powder free latex surgical gloves,

place a labeled (identified) and weighed filter

holder assembly in the stainless holder for

the assembly. Then place this whole unit in

the Method 5 hot box and attach it to the

probe using clean standard connectors. Do

not use any stopcock grease.

4.2 Sample Recovery. Proper cleanup

procedure begins as soon as the probe is

removed from the stack at the end of the

sampling period. Allow the probe to cool.

When the probe can be safely handled, wipe

off all external particulate matter near the tip

of the probe nozzle and place a cap over it

to prevent losing or gaining particulate

matter. Do not cap off the probe tip tightly

while the sampling train is cooling down as

this would create a vacuum in the filter

holder, thus drawing water from the

impingers into the filter holder. Before
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moving the sample train to the cleanup site,

remove the probe from the sample train and

cap the open outlet of the probe. Be careful

not to lose any condensate that might be

present. Cap the filter inlet using a standard

ground glass plug and secure the cap with an

impinger clamp. Remove the umbilical cord

from the last impinger and cap the impinger.

If a flexible line is used between the first

impinger or condenser and the filter holder,

disconnect the line at the filter holder and let

any condensed water or liquid drain into the

impingers or condenser. Transfer the probe

and filter-impinger assembly to the cleanup

area. This area should be clean and protected

from the wind so that the chances of

contaminating or losing the sample will be

minimized. Save a portion of the acetone

used for cleanup of the probe and nozzle as

a blank. Take 200 ml of this acetone directly

from the wash bottle being used and place it

in a glass sample container labeled ‘‘acetone

blank.’’ Inspect the train prior to and during

disassembly and note any abnormal

conditions. Treat the samples as follows:

Container No. 1. Carefully remove the filter

holder assembly from the Method 5 hot box

and place it in the transport case. Use a pair

of clean disposable powder free latex surgical

gloves to handle the filter holder assembly.

If the transport case is being used to identify

and track the filter holder assemblies the

entire transport container will need to be of

sufficient size and shape to fit in the

desiccator at the laboratory. It is important to

ensure that the assemblies have cooled

sufficiently to prevent the surgical gloves

from melting on the filter holder assembly.

Container No. 2. Same as Method 5

Container No. 2 with the exception that it is

recommended that only glass sample

containers be used for collection of the

sample from the probe and nozzle to

minimize the potential for background

contamination.

Container No. 3. Same as Method 5

Container No. 3.

4.3 Analysis. Same as Method 5 section

4.3 with the following exceptions:

Container No. 1. Same as Method 5 Section

4.3 Container No. 1 with the following

exception: Use disposable powder free latex

surgical gloves to remove each of the filter

holder assemblies from the desiccator or

transport container.

Container No. 2. Same as Method 5 Section

4.3 Container No. 2 with the following

exception: It is recommended that the

contents of Container 2 be transferred to a

250 ml beaker with a Teflon liner or similar

container that has a minimal tare weight

prior to bringing to dryness.

Container No. 3. Same as Method 5 Section

4.3 Container No. 3

4.4 Quality Control Procedures. The

Quality Control Procedures used in sampling

are the same as Method 5 for: Meter Orifice

Check and Calibrated Critical Orifice

(sections 4.4.1—4.4.2).

5. Calibration.

The Calibration Procedures used are the

same as Method 5: Probe Nozzle, Pitot Tube,

Metering System, Probe Heater Calibration,

Temperature Gauges, Leak Check of Metering

System Shown in Method 5 Figure 5–1,

Barometer (sections 5.1—5.7).

6. Calculations

The Calculations used are the same as

Method 5 for: Nomenclature, Average Dry

Gas Meter Temperature and Average Orifice

Pressure Drop, Dry Gas Volume, Volume of

Water Vapor, Acetone Blank Concentration,

Total Particulate Weight, Particulate

Concentration, Conversion Factors, Isokinetic

Variation, Acceptable Results, Stack Gas

Velocity and Volumetric Flow Rate (sections

6.1—6.13).

7. Alternative Procedures

The Alternative Procedures used are the

same as Method 5 for: Dry Gas Meter as a

Calibration Standard, Critical Orifices As

Calibration Standards, (sections 7.1—7.2).

8. Bibliography

The Bibliography used is the same as

Method 5.

BILLING CODE 6560–50–P
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BILLING CODE 6560–50–C
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Appendix II—Performance

Specification 11

PERFORMANCE SPECIFICATION 11—

Specifications and test procedures for

particulate matter continuous emission

monitoring systems in stationary sources.

211.0 Scope and Application

1.1 Analyte. Particulate matter as defined

and determined by the Reference Method—

Method 5 or Method 5I.

1.2 Applicability.

1.2.1 This specification is for evaluating

the acceptability of particulate matter (PM)

continuous emission monitoring systems

(CEMS) at the time of or soon after

installation and whenever specified in the

regulations. The CEMS may include, for

certain stationary sources, (a) a diluent

monitor (i.e., O2, CO, or other CEMS

specified in the applicable regulation), which

must meet its own performance

specifications found in this appendix, (b)

auxiliary monitoring equipment to allow

measurement, determination, or input of the

gas temperature, pressure, moisture content,

and/or dry volume of stack effluent sampled,

and (c) an automatic sampling system.

This performance specification requires

site specific calibration of the PM CEMS

response against manual gravimetric

Reference Method measurements. Procedures

for extrapolating results beyond the range of

particulate mass loadings used to develop the

calibration are found in the applicable

regulations. A new calibration may be

required if conditions at the facility change

and result in conditions which are

unrepresentative of the previous calibration

(i.e., changes in emission control system,

concentration of PM emitted, or feed inputs

to the device). Since the validity of the

calibration may be affected by changes in the

physical properties of the particulate (such as

density, index of refraction, and size

distribution), the limitations of the CEMS

used should be evaluated with respect to

these possible changes on a site specific

basis.

1.2.2 This specification is not designed to

evaluate the installed CEMS performance

over an extended period of time nor does it

identify specific calibration techniques and

auxiliary procedures to assess CEMS

performance. The source owner or operator,

however, is responsible to properly calibrate,

maintain, and operate the CEMS. The

Administrator may require, under Section

114 of the Act, the operator to conduct CEMS

performance evaluations at other times

besides the initial test to evaluate the CEMS

performance. See Appendix F to Part 60—

Procedure 2, Quality Assurance

Requirements For Particulate Matter

Continuous Emission Monitoring Systems

Used For Compliance Determination.

2.0 Summary of Performance Specification.

Procedures for establishing the CEMS

calibration are outlined in this performance

specification. CEMS installation and

measurement location specifications,

equipment specifications, performance

specifications, and data reduction procedures

are also included. Conformance of the CEMS

with the Performance Specifications is

determined.

3.0 Definitions

3.1 Batch Sampling means the technique

of sampling the stack effluent continuously

and concentrating the pollutant in some

capture medium. The capture medium is

moved periodically for analysis after

sufficient time has elapsed to concentrate the

pollutant to levels detectable by the analyzer.

Continuous sampling is ensured by sampling

(either on a different part of the capture

medium or a different capture medium)

while analysis is being performed on a

previous sample.

3.2 Calibration Drift (CD) means the

difference in the CEMS output readings from

the established reference value after a stated

period of operation during which no

unscheduled maintenance, repair, or manual

adjustment took place.

3.3 Calibration means the site-specific

correlation between the CEMS output and the

PM mass concentration measured by the

Reference Method.

3.4 Calibration Standard means a

reference material that produces a known

and unchanging response when presented to

the pollutant analyzer portion of the CEMS,

and used to calibrate the drift or response of

the analyzer.

3.5 Centroidal Area means a concentric

area that is geometrically similar to the stack

or duct cross section and is no greater than

1 percent of the stack or duct cross sectional

area.

3.6 Confidence Interval means the

interval defined by equations 13 and 23 of

this performance specification with upper

and lower limits within which the CEMS

response calibration relation lies with a given

level of confidence.

3.7 Continuous Emission Monitoring

System (CEMS) means the total equipment

required for the determination of particulate

matter mass concentration in units of the

emission standard. The sample interface,

pollutant analyzer, diluent analyzer, other

auxiliary data monitor(s) and data recorder

are the major subsystems of the CEMS.

3.8 Correlation coefficient means that

portion of the statistical evaluation that

measures how well the CEMS and Reference

Method calibration relation data fit the

regression line as defined by equation 16 of

this performance specification.

3.9 Data Recorder means that portion of

the CEMS that provides a permanent record

of the analyzer output and the final PM

concentration result in units of the emission

standard. The data recorder may provide

automatic data reduction and CEMS control

capabilities.

3.10 Diluent Analyzer and Other

Auxiliary Data Monitor(s) (if applicable)

means that portion of the CEMS that sense

or otherwise provide the diluent gas (such as

O2 or CO, as specified by the applicable

regulations), temperature, pressure, and/or

moisture content, and generates an output

proportional to the diluent gas concentration

or data property.

3.11 Linear Calibration means a CEMS

response which is linear relative to the

measured PM concentration produced by the

Reference Method.

3.12 Path CEMS means a CEMS that

measures particulate matter mass

concentrations along a path across the stack

or duct cross section which is representative

of results of the cross-sectional PM

concentrations produced by the Reference

Method.

3.13 Point CEMS means a CEMS that

measures particulate matter mass

concentrations either at a single point, or

over a small fixed volume or path, which is

representative of the cross-sectional PM

concentrations produced by the Reference

Method.

3.14 Pollutant Analyzer means that

portion of the CEMS that senses the

particulate matter concentration and

generates a proportional output.

3.15 Quadratic Calibration Relation

means a CEMS response which has a second

order equation to define its relationship to

the measured PM concentration produced by

the Reference Method.

3.16 Reference Method. The Reference

Method for particulate measurements is those

methods collectively known as Method 5,

found in Appendix A of 40 CFR Part 60.

Unless other variants are specified in the

regulations, Method 5 shall be used for total

train catches exceeding 50 mg (i.e., emissions

concentrations of more than 45 mg/dscm).

Method 5I shall be used for total train catches

of less than or equal to 50 mg (i.e., emissions

concentrations of 45 mg/dscm or less). If

variants other than Method 5I are used, care

should be taken to follow the general

procedures described in Method 5I to aid in

the elimination of measurement error. Other

Reference Methods may be applicable, such

as Method 1, 3, or 4. Methods other than

Method 5 are referred to in this specification

individually by name.

3.17 Representative Results means the

results consistent with the acceptance criteria

found in section 13.2 of this specification.

3.18 Response Time means the time

interval between the start of a step change in

the system input and the time when the

pollutant analyzer output reaches 95 percent

of the final value.

3.19 Sample Interface means that portion

of the CEMS used for one or more of the

following: sample acquisition, sample

delivery, sample conditioning, or protection

of the monitor from the effects of the stack

effluent.

3.20 Span Value means the upper limit of

the CEMS measurement range. The span

value shall be documented by the CEMS

manufacturer with laboratory data.

3.21 Tolerance Interval means the interval

with upper and lower limits within which

are contained a specified percentage of the

population with a given level of confidence

as defined by equation 14 of this performance

specification.

3.22 Zero Drift (ZD) means the difference

in the CEMS output readings for zero input

after a stated period of operation during

which no unscheduled maintenance, repair,

or adjustment took place.

4.0 Interferences

In the Reference Method a representative

sample of particulate is collected on a filter

maintained at a temperature in the range
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specified by the method, and includes any

material that deposits in sample delivery and

condenses at or above this filtration

temperature after removal of any combined

water. Consequently, condensible water

droplets or condensible acid gas aerosols

(i.e., those with condensation temperatures

above those specified by the method) at the

measurement location can be interferences

for PM CEMS if the necessary precautions are

not systematically met. Interferences may

develop for CEMS installed downstream of a

wet air pollution control system or any other

conditions that produce flue gases which are

normally or occasionally saturated with

water or acid gases prior to release to the

atmosphere. For such conditions, the CEMS

must extract and heat a representative sample

of the flue gas for measurement to simulate

results produced by the Reference Method.

Independent of the CEMS measurement

technology and extractive technique, a

configuration simulating the Reference

Method is required to assure that: (1) there

is no formation or deposition of particulate

in sample delivery from the stack or duct;

and (2) the pollutant analyzer portion of the

CEMS measures only native particulate.

Performance of a CEMS design configured to

eliminate interferences with condensible

water and/or acid gases must be documented

by the CEMS manufacturer (see Section 6.1.3

of this performance specification for specific

equipment heating requirements). In-situ

CEMS measurement technologies that are not

free of interferences from any condensible

constituent in the flue gas are prohibited in

stack or duct flue gas conditions which are

normally or occasionally saturated with

water or acid gases.

5.0 Safety

The procedures required under this

performance specification may involve

hazardous materials, operations, site

conditions, and equipment. This

performance specification does not purport

to address all of the safety problems

associated with these procedures. It is the

responsibility of the user to establish

appropriate safety and health practices and

determine the applicable regulatory

limitations prior to performing these

procedures. The CEMS users’ manual and

materials recommended by the Reference

Method should be consulted for specific

precautions to be taken.

6.0 Equipment and Supplies

6.1 CEMS Equipment Specifications

6.1.1 Data Recorder Scale. The CEMS

data recorder output range must include zero

and a high level value. The high level value

is chosen by the source owner or operator

and is defined as follows:

6.1.1.1 For a CEMS installed to measure

emissions as required with an applicable

regulation, the high level value between 1.5

times the emission standard and the span

value specified in the applicable regulation is

adequate.

6.1.1.2 Alternative high-level values may

be used, provided the source can measure

emissions throughout the full range of

emissions concentrations experienced by the

facility.

6.1.1.3 The data recorder output must be

established so that the high level value

would read between 90 and 100 percent of

the data recorder full scale. (This scale

requirement may only be applicable to analog

data recorders.) The zero and high level

calibration gas, filter, or other appropriate

media values should be used to establish the

data recorder scale.

6.1.1.4 The high level value must be equal

to the span value. If a lower high level value

is used, the CEMS must have the capability

of providing multiple outputs with different

high level values (one of which is equal to

the span value) or be capable of

automatically changing the high level value

as required (up to the span value) such that

the measured value does not exceed 95

percent of the high level value.

6.1.1.5 Span. The span of the instrument

shall be sufficient to determine the highest

concentration of pollutant at the facility. The

span value shall be documented by the CEMS

manufacturer with laboratory data.

6.1.2 The CEMS design should also allow

daily determination and recording of

calibration drift at the zero and high-level

values. If this is not possible or practical, the

design must allow these determinations and

recordings to be conducted at a low-level

(zero to 20 percent of the high-level value)

and at a value between 50 and 100 percent

of the high-level value. In special cases, the

Administrator may approve a single-point

calibration drift determination.

6.1.3 Specification for Saturated Flue Gas.

For a CEMS installed downstream of a wet

air pollution control system such that the

flue gases are normally or occasionally

saturated with water, then the CEMS must

have equipment to extract and heat a

representative sample of the flue gas for

measurement so that the pollutant analyzer

portion of the CEMS measures only dry

particulate. Heating shall be sufficient to

raise the temperature of the extracted flue gas

to above the water condensation temperature

and shall be maintained at all times and at

all points in the sample line from where the

flue gas is extracted to and including the

pollutant analyzer. Performance of a CEMS

design configured in this manner must be

documented by the CEMS manufacturer.

6.2 Sampling and Response Time. The

CEMS shall sample the stack effluent

continuously or intermittently for batch

sampling CEMS. Averaging time, the number

of measurements in an average, the minimum

sampling time, and the averaging procedure

for reporting and determining compliance

shall conform with those specified in the

applicable emission regulation.

6.2.1 Response Time. The response time of

the CEMS should not exceed 2 minutes to

achieve 95 percent of the final stable value

(except for Batch CEMS: see 6.2.2). The

response time shall be documented and

provided by the CEMS manufacturer. Any

changes in the response time following

installation shall be documented and

maintained by the facility.

6.2.2 Response Time for Batch CEMS.

The response time requirement of Section

6.2.1 does not apply to batch CEMS. Instead

it is required that the response time, which

is the equivalent to the cycle time, be no

longer than one tenth of the averaging period

for the applicable standard or no longer than

fifteen minutes, whichever is greater. In

addition, the delay between the end of the

sampling time and reporting of the sample

analysis shall be no greater than three

minutes. Any changes in the response time

following installation shall be documented

and maintained by the owner or operator.

6.2.3 Sampling Time for Batch CEMS.

Sampling is required to be continuous except

during brief pauses when the collected

pollutant on the capture media is being

moved for analysis and the next capture

medium starts sampling. In addition, the

sampling time should be no less than thirtyfive percent of the averaging period for the

applicable standard or no less than thirty-five

percent of the response time.

6.3 Other equipment and supplies, as

needed by the applicable Reference

Method(s) (see Section 8.4.2 of this

Performance Specification) or as specified by

the CEMS manufacturer, may be required.

7.0 Reagents and Standards

7.1 Reference Gases, Optical filters, or

other technology-appropriate reference

media. As specified by the CEMS

manufacturer for internal calibration (i.e., to

adjust drift or response) of the CEMS. These

need not be certified but shall be

documented by the manufacturer to give

results consistent with this performance

specification.

7.2 Reagents and Standards. May be

required as needed by the applicable

Reference Method(s) (see Section 8.4.2) of

this performance specification).

8.0 Performance Specification Test

Procedure

8.1 Installation and Measurement Location

Specifications.

8.1.1 CEMS Installation. Install the CEMS

at an accessible location downstream of all

pollution control equipment where the

particulate matter mass concentrations

measurements are representative or can be

corrected to be representative of the total

emissions as determined by the Reference

Method from the affected facility or at the

measurement location cross section. It is

important to select a representative

measurement point(s) or path(s) for

monitoring in location(s) that the CEMS will

pass the calibration test (see Section 8.4). If

the cause of failure to meet the calibration

relation test is determined to be the

measurement location and a satisfactory

correction technique cannot be established,

the Administrator may require the CEMS to

be relocated. Suggested measurement

locations and points or paths that are most

likely to provide data that will meet the

calibration requirements are listed below.

8.1.2 Measurement Location. It is

suggested that the measurement location be:

(1) at least eight equivalent diameters

downstream from the nearest flow

disturbance, such as a control device, point

of pollutant generation, bend, expansion,

contraction in the stack/duct, point of

discharge, or other point at which a change

of pollutant concentration or gas streamlines

may occur; and (2) at least two equivalent
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diameter upstream from the effluent exhaust

or a flow disturbance.

8.1.2.1 Point CEMS. It is suggested that the

measurement point be: (1) no less than 30%

of the stack or duct diameter from the stack

or duct wall; or (2) within or centrally

located over the centroidal area of the stack

or duct cross section.

8.1.2.2 Path CEMS. It is suggested that the

effective measurement path be : (1) totally

within the inner area bounded by a line 30

percent of the stack/duct diameter from the

stack or duct wall; (2) have at least 70 percent

of the path within the inner 50 percent of the

stack or duct cross sectional area; or (3) be

centrally located over any part of the

centroidal area.

8.1.3 Reference Method Measurement

Location and Traverse Points.

8.1.3.1 Select, as appropriate: (1) an

accessible Reference Method measurement

point at least eight equivalent diameters

downstream from the nearest flow

disturbance, such as a control device, point

of pollutant generation, bend, expansion,

contraction in the stack or duct discharge

point, or other point at which a change of

pollutant concentration or gas flow direction

may occur; and (2) at least two equivalent

diameters upstream from the flow

disturbance, such as the effluent exhaust.

When pollutant concentration changes are

due solely to diluent leakage (e.g., air heater

leakages) and pollutants and diluents are

simultaneously measured at the same

location, a half diameter may be used in lieu

of two equivalent diameters. The CEMS and

Reference Method locations need not be the

same so long as the Reference Method is

placed at a location specified by the method

and the CEMS output is representative of

pollutant emissions determined by the

Reference Method.

8.1.3.2 Select traverse points that assure

acquisition of representative samples over

the stack or duct cross section. Selection of

traverse points to determine the

representativeness of the measurement

location should be made according to 40 CFR

part 60, Appendix A, Method 1, Section 2.2

and 2.3.

8.2 Pretest Preparation. Install the CEMS,

prepare the Reference Method test site

according to the specifications in Section 8.1,

and prepare the CEMS for operation

according to the manufacturer’s written

instructions.

8.3 Calibration Drift Test Procedure.

8.3.1 CD test Period. While the affected

facility is operating more than 50 percent of

normal load, or as specified in an applicable

Subpart, determine the magnitude of the CD

once each day (at 24-hour intervals) for 7

consecutive days according to the procedure

given in Sections 8.3.2 and 8.3.3.

8.3.2 The purpose of the CD measurement

is to verify the ability of the CEMS to

conform to the established CEMS calibration

used for determining the emission

concentration or emission rate. Therefore, if

periodic automatic or manual adjustments

are made to the CEMS zero and calibration

settings, conduct the CD test immediately

before these adjustments, or conduct it in

such a way that the CD can be determined.

8.3.3 Conduct the CD test at the two

points specified in Section 6.1.2. Introduce to

the CEMS the reference gases, optical filters,

or other suitable calibration reference media

(these need not be certified). Record the

CEMS response and subtract this value from

the reference value.

8.4 Calibration Test Procedure

8.4.1 Calibration Test Period. Conduct the

calibration test according to the procedure

given in Sections 8.4.2 through 8.4.7 while

the affected facility is operating at more than

50 percent of normal load or as specified in

an applicable Subpart. The calibration test

may be conducted during the CD test period.

8.4.2 Reference Methods. Unless

otherwise specified in an applicable Subpart

of the regulations, Method 3B, 4, and 5I, or

other approved alternatives, are the

Reference Methods for diluent (O2), moisture,

and PM, respectively. Method 5 should be

used instead of Method 5I if PM emissions

exceed 45 mg/dscm (0.02 gr/dscf).

8.4.3 Sampling Strategy for Reference

Method tests. Conduct the Reference Method

tests in such a way that they will yield

results representative of the emissions from

the source and can be correlated to the CEMS

data. Conduct the diluent (if applicable),

moisture, (if needed), and PM measurements

simultaneously. In order to correlate the

CEMS and Reference Method data properly,

make sure the time from the CEMS data

recorder and the time instrument used for the

Reference Method agree and note the

beginning and end of each Reference Method

test period of each run (including the exact

time of day) on the CEMS chart recordings

or other permanent record of output. Make

two sample traverses for a total of at least 60

minutes, sampling for an equal time at each

traverse point (see Section 8.1.3.2 for

discussion of traverse points). The use of

paired Method 5I (or Method 5 as

appropriate) trains (that is, simultaneously

traversing across two 90°-opposed axes) is

recommended to improve and assure data

quality.

Note: At times, CEMS calibration tests may

be conducted during new source

performance standards, performance tests or

other compliance tests subject to the Clean

Air Act or other statutes, such as the

Resource Conservation and Recovery Act. In

these cases, Reference Method results

obtained during CEMS calibration test may

be used to determine compliance as long as

the source and test conditions are consistent

with the applicable regulations.

8.4.4 Number of Runs in a Calibration

Relation Test. Conduct a minimum of 15 runs

each consisting of simultaneous CEMS and

Reference Method measurements sets.

Note: More than 15 sets of CEMS and

Reference Method measurement sets may be

performed. If this option is chosen, certain

test results may be rejected so long as the

total number of test results used to determine

the calibration relation is greater than or

equal to 15. However, all data must be

reported, including the rejected data. The

basis for rejecting data must be explicitly

stated in: (1) The Reference Method, this

Performance Specification, or Procedure 2; or

(2) the site’s QA plan approved by the

Administrator.

8.4.5 Structure of Tests. CEMS calibration

tests shall be carried out by making

simultaneous CEMS and Reference Method

measurement sets at three (or more) different

levels of PM mass concentrations over the

full range of operations experienced by the

facility, including emissions. Three (or more)

sets of measurements shall be obtained at

each level. The different levels of PM mass

concentration should be obtained by varying

process or PM control device conditions as

much as the process allows. If it is not

possible or practical to obtain PM

measurement at the standard, it is

recommended that at least six measurement

sets be performed at the maximum PM

emission level achievable to produce the

most accurate and representative results.

This will help obtain the smallest confidence

and tolerance intervals at the maximum

emission level. Irrespective of the extent of

the range, the three PM concentration levels

developed in the calibration tests must be

distributed over the complete operating range

experienced by the facility, and at least three

of the minimum 15 measured data points

must lie within each of the following levels:

• Level 1: 0 to 30% of the maximum PM

concentration;

• Level 2: 30 to 60% of the maximum PM

concentration; and

• Level 3: 60 to 100% of the maximum PM

concentration.

8.4.6 Correlation of Reference Method

and CEMS Data. If necessary, adjust the

CEMS outputs and Reference Method test

data to the same time. Determine the

integrated (arithmetic average) CEMS output

over each Reference Method test period.

Consider system response time, if important,

and confirm that the pair of results are on a

consistent moisture, temperature, and diluent

concentration basis. Adjust the Reference

Method results to ensure they are on the

same basis as the CEMS measurements.

Depending on the particular CEMS

measurement conditions, the CEMS and

Method 5I (or Method 5 where applicable)

correlations are based on either:

(a) Actual in-stack conditions and actual

PM concentrations for in-situ CEMS in mg/

acm (i.e., account for the in-stack

temperature, pressure, and moisture),

(b) Actual CEMS measurement conditions

for extractive CEMS in mg/acm (i.e., account

for the elevated temperature of the extracted

flue gas if heated), or

(c) Dry standard conditions and

corresponding PM concentrations in mg/

dscm (i.e., do not correct the Reference

Method results if the CEMS outputs are on

the same temperature and moisture basis as

the Reference Method). Calculate the

appropriate PM concentrations as specified

by CEMS manufacturer using the applicable

equations in Section 12.0.

8.4.7 Calculate the correlation coefficient,

confidence interval, and tolerance interval

for the complete set of CEMS/RM data

according to the procedures in Section 12.0.

8.5 Number of Calibration Tests

Because of the need to develop a

calibration curve representative of the

facility/APC system, the following strategy

will ensure that the calibration curve

facilities develop adequately corresponds to

measured PM concentrations:

Perform the initial calibration test and

develop a correlation within the time period
67810 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

specified in the applicable regulation. For

CEMS with measurement technologies

insensitive to changes in PM properties (e.g.,

Beta-gage), this would be the only calibration

test required.

For CEMS with measurement technologies

sensitive to PM property changes (e.g., Lightscattering), perform a second calibration

within the time period specified in the

applicable regulation. Compare the results of

the two calibrations to determine what type

of mathematical model (e.g., arithmetic, lognormal, or quadratic) best correlates with

measured PM concentrations. The calibration

for the facility is a composite of both sets of

calibration data. Perform a third calibration

test within the time period specified in the

applicable regulation. Compare the third

calibration to the first two. If this calibration

relation confirms the findings of the original

two calibrations, then this is the last

calibration test to be performed. The final

calibration relation for the facility is a

composite of all three sets of calibration data.

If the third calibration shows some fit other

than the one originally determined best

correlates CEMS response to PM emission

concentrations, then a fourth calibration test

must be performed within the time period

specified in the applicable regulation. This

process of performing additional calibration

test continues until the facility can determine

what fit best correlates CEMS output to PM

concentrations. The final calibration is a

composite of all calibration data obtained.

8.6 Reporting. At a minimum, (check

with the appropriate regional office, State, or

Local agency for additional requirements, if

any), summarize in tabular form the results

of the CD tests and the calibration tests, as

appropriate. Include all data sheets,

calculations, charts (records of CEMS

responses), process data records including

PM control equipment operating parameters,

and manufacturer’s reference calibration

media certifications necessary to confirm that

the performance of the CEMS met the

performance specifications.

9.0 Quality Control. [Reserved]

10.0 Calibration and Standardization.

[Reserved]

11.0 Analytical Procedure.

Sample collection and analysis are

concurrent for this Performance Specification

(see Section 8.0). Refer to the Reference

Method for specific analytical procedures.

12.0 Calculations and Data Analysis.

Summarize the results on a data sheet

similar to that shown in Table III (in Section

18.0).

12.1 Calibration and Zero Drift

12.1.1 Calibration Drift. Calculate the CD

according to:

CD

R R

R

CEM V

V

= ( ) − ×100 1 , ( )

where:

CD=the calibration drift of the CEMS in

percent

RCEM=the CEMS response; and

RV=the reference value of the high level

calibration standard.

12.1.2 Calculate the ZD according to:

ZD

R R

R

CEM V

EM

= ( ) − ×100 2 , ( )

where:

ZD=the zero drift of the CEMS in percent.

12.2 Calibration Evaluation

12.2.1 Treatment of Reference Method

Data. All data from the Reference Method

and CEMS must be on the same basis. Correct

the Reference Method data for moisture,

temperature, and pressure to the same units

as the CEMS using the equations below.

Depending on the particular CEMS

measurement conditions, the CEMS and

Reference Method correlation is based on

either:

(a) Actual in-stack conditions and actual

PM concentrations for in-situ monitors

expressed in mg/acm (i.e., to account for the

in-stack temperature and moisture),

(b) Elevated CEMS temperature conditions

and corresponding PM concentrations in mg/

acm at the analyzer (i.e., to account for the

increased temperature, relative to in-stack

levels, in extracted sample gas temperature),

or

(c) Dry standard conditions and

corresponding PM concentrations in mg/

dscm (i.e., to account for the moisture

condensed in drying the extracted sample

before measuring gas volume, analogous to

the Reference Method).

Calculate the respective PM concentrations

using the equations, below.

Refer to the Results produced from the CFR

Method 5, Section 6.9, Equation 5–6;

Particulate Concentration Calculation in dry

standard units.

C g mg m

V s n

m std

= 









 ( . / ) ( )

( )

0 001 4

where:

Cs=Concentration in mg/dscm

mn=Total amount of particulate matter

collected, mg.

Vm(std)=Volume of gas sample as measured

by dry gas meter, corrected to standard

condition, dscm.

12.2.2 Conversion of Reference Method

Particulate Concentrations to Other Units

where:

C=Concentration at actual stack conditions

(mg/Acm),

Cs=Concentration at mg/dscm,

Cs@7%=Concentration at mg/dscm at 7%

O2,

ts=Average stack gas temperature °F,

P=Absolute stack pressure (in Hg),

Bws=Water Vapor in the gas stream,

proportion by volume, and

O2=Stack Gas Oxygen Content.

(a) From dry standard concentration

conditions to actual in stack conditions (as

applicable).

C C R

t

P

inHg s B

s

= ( ) ws ( ) + ( ) − 528

460 29 92

1 5

o

. ( )

(b) From dry standard concentration

conditions to dry standard concentration at 7

%O2.

C C

O S S @

( . )

. ( ) 7%

2

20 9 7

20 9 = 6 −−

(c) From actual stack conditions to dry

standard concentration.

C C

t

R

inHg

P B S

s

ws

@

. ( ) 7%

460

528

29 92 1

1 = 7 ( ) +

( ) − o
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67811

12.2.3 Linear Calibration. A linear

calibration (i.e., linear correlation) shall be

calculated from the calibration data by

performing a linear least squares regression.

The CEMS data appear on the x axis, and the

Reference Method data appear on the y axis.

Whether this fit is used depends on the

outcome of the calculations described in

section 12.2.5 of this performance

specification.

12.2.3.1 Linear Regression. The linear

regression, which gives the predicted mass

emission,yˆ, based on the CEMS response x,

is given by the equation:

y m x b ˆ = ⋅ + ( ) 7

where:

m

S

S

xy

xx

= ( ) 8

and

b y m x = − ⋅ ( ) 9

The mean values of the x and y data sets

are given by

x nx y

n

i y

i

n

i

i

n

= =

= =

∑ ∑ 1 1 10

1 1

, ( )

where xi and yi are the absolute values of the

individual measurements and n is the

number of data points. The values Sxx, Syy,

and Sxy are given by

S x x S y y S x x y y xx i yy i xy i

i

n

i

n

i

n

= − ( ) = − ( ) = − ( ) i ⋅ − ( ) = = =

∑ ∑ ∑ 2 2

1 1 1

, , ( ) 11

from which the scatter of y values about the

regression line (calibration) sL can be

determined:

S

S

n

S

S S L

yy xy

xx yy

= − − ⋅











 2

1 12

2

( )

12.2.3.2 Confidence Interval. The twosided confidence interval, yc,, for thepredicted concentration yˆ at point x is given

by the equation:

y y t s

n

x x

S

with f c f L

xx

= ± ⋅ + ( ) − ˆ − , ( ) 1 2 13

2

= n

12.2.3.3 Tolerance Interval. The twosided tolerance interval yt for the regression

line is given by the equation:

y y k s T T L = ± ⋅ ˆ ( ) 14

at the point x with kT=un′ and f=n¥2, where
67812 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

n

n

n x x

S

n

xx

' , = ' . ( )

+ ⋅ − ( )

≥

1

2 15 2

The tolerance factor un

• for 75% of the

population is given in Table I as a function

of n′. The factor vf as a function of f is also

given in Table I as well as the t-factor at the

95% confidence level.

12.2.3.4 Correlation Coefficient. The

correlation coefficient r may be calculated

from

r m

S

S

xx

yy

= . ( ) 16

12.2.4 Quadratic Calibration Relation. In

some cases, a quadratic regression will

provide a better fit to the calibration data

than a linear regression. The CEMS data

appear on the x axis, and the Reference

Method data appear on the y axis. A test to

determine whether the quadratic regression

gives a better fit to the data than a linear

regression must be performed. The relation

with the best fit must be used.

12.2.4.1 Quadratic Regression. A leastsquares quadratic regression gives the best fit

coefficients b0, b1, and b2 for the calibration

relation:

y b b x b x ˆ = + + ( ) 0 1 2

2 17

The coefficients b0, b1, and b2 are

determined from the solution to the matrix

equation Ab=B

where:

A

n S S

S S S

S S S

b

b

b

b

B

S

S

S

and

S x S x S x S x i

i

n

i i i

i

n

i

n

=





















=





















=





















= ( ) = ( ) = ( ) = ( ) = = =

∑ ∑

1 2

1 2 3

2 3 4

0

1

2

5

6

7

1

1

2

2

3

3

4

4

1 1

, , .

, , , ∑ ∑

∑ ∑ ∑

=

= = =

= = ( ) = ( )

i

n

i i i i i

i

n

i

n

i

n

S y S x y S x y

1

5 6 7

2

1 1 1

, ( ) 18

, , .

The solutions to b0, b1, and b2 are:

b S S S S S S S S S S S S S S S S S S A 0 5 2 4 1 3 7 2 6 3 7 2 2 3 3 5 4 6 1 = ⋅ ⋅ + ⋅ ⋅ + ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ ( )/det ( ) 19

b n S S S S S S S S S S S S S n S S S A 1 6 4 5 3 2 2 1 7 2 6 2 7 3 4 1 5 = ⋅ ⋅ + ⋅ ⋅ + ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ ( )/det ( ) 20

b n S S S S S S S S S S S S S n S S S A 2 2 7 1 6 2 = ⋅ ⋅ + ⋅ ⋅ + ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ ( ) 5 1 3 2 2 5 3 6 7 1 1 /det ( ) 21

where:

det ( ) A n S S S S S S S S S S S S S S S S S = ⋅ ⋅ + ⋅ ⋅ + ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ − ⋅ ⋅ 2 4 1 3 2 2 1 3 2 2 2 3 3 2 4 1 1 22

12.2.4.2 Confidence Interval. For any

positive value of x, the confidence interval is

given by:

y y t s CI f Q = ± ⋅ ˆ ∆ ( ) 23

where:

f = n¥3,

tf is given in Table I,

( ( ) 24

C ( ) 25
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67813

The C coefficients are given below:

C S S S D C S S S S D C S S S D

C nS S D C S S nS D C nS S D

0 2 4 3

2

1 3 2 1 4 2 1 3 2

2

3 4 2

2

4 1 2 3 5 2 1

2 26

= ⋅ − ( ) = ⋅ − ⋅ ( ) = ⋅ − ( )

= − ( ) = ⋅ − ( ) = − ( )

/ , / , / ,

/ , / , / . ( )

where

D n S S S S S S S S S S S S = ⋅ − ( ) 2 4 3 + ⋅ − ⋅ ( ) + ⋅ − ( ) 2

1 3 2 1 4 2 1 3 2

2 . ( ) 27

12.2.4.3 Tolerance Interval. For any positive value of x, the tolerance interval is given by:

y y k s TI T Q = ± ⋅ ˆ , ( ) 28

where:

k u v with f n T n f = ⋅ = ' -3, and (29)

n with n ' / ' . ( ) = ≥ 1 2 30 ∆

The vf and un’ factors can also be found in

Table I.

12.2.5 Test to Determine Best Regression

Fit. The test to determine if the fit using a

quadratic regression is better than the fit

using a linear regression is based on the

values of s calculated in the two

formulations. If sL denotes the value of s from

the linear regression and sQ the value of s

from the quadratic regression, then the

quadratic regression gives a better fit at the

95% confidence level if the following

relationship is fulfilled:

( ) ( )n s n s

s

F L Q

Q

f

− ⋅ − − ( )⋅ >2 3

31

2 2

2

with f = n-3 and the value of Ff at the 95%

confidence level as a function of f taken from

Table II below.

12.2.6 Alternative Mathematical

Approaches to the Calibration. Other nonlinear relations may provide a better fit to the

calibration data than linear or quadratic

relations because of the monitor’s response to

some measurable property indicative of the

PM concentration. These approaches may

serve as alternative approaches for defining

the mathematical relation between the CEMS

response and the Reference Method. The

basis for developing such alternative

approaches must be explicitly included in

the calibration relation test report with

supporting data demonstrating a better fit

than linear and quadratic relations and is

subject to approval by the Administrator.

13.0 Method Performance

13.1 Calibration Drift Performance

Specification. The CEMS internal calibration

must not drift or deviate from the value of

the reference light, optical filter, Beta

attenuation signal, or other technologysuitable calibration reference media by more

than 2 percent of the span value. If the CEMS

includes diluent and/or auxiliary monitors

(for temperature, pressure, and/or moisture)

that are employed as a necessary part of this

performance specification, the CD must then

be determined separately for each in terms of

its respective output (see the appropriate

Performance Specification for the diluent

CEMS specification). None of the CDS may

exceed the specification.

13.2 Calibration Relation Performance

Specifications. The CEMS calibration relation

must meet each of the following minimum

specifications for all three criteria.

Criterion A. The correlation coefficient

shall be greater than or equal to 0.90.

Criterion B. The confidence interval (95%)

at the emission limit shall be within 10% of

the emission limit value specified in the

regulations.

Criterion C. The tolerance interval at the

emission limit shall have 95% confidence

that 75% of all possible values are within

25% of the emission limit value specified in

the regulations.

13.3 PM Compliance Monitoring. The

CEMS measurements shall be reported to the

Agency in the units of the standard expressed

in the regulations (i.e., mg/dscm,

14.0 Pollution Prevention. [Reserved]

15.0 Waste Management. [Reserved]

16.0 Alternative Procedures. [Reserved]

17.0 References

1. 40 CFR part 60, Appendix B,

‘‘Performance Specification 2—Specifications

and Test Procedures for S02 and NOx,

Continuous Emission Monitoring Systems in

Stationary Sources.’’

2. 40 CFR part 60, Appendix B,

‘‘Performance Specification I—Specification

and Test Procedures for Opacity Continuous

Emission Monitoring Systems in Stationary

Sources.

3. 40 CFR part 60, Appendix A, ‘‘Method

1—Sample and Velocity Traverses for

Stationary Sources.’’

4. 40 CFR part 266, Appendix IX, Section

2, ‘‘Performance Specifications for

Continuous Emission Monitoring Systems.’’

5. ISO 10155, ‘‘Stationary Source

Emissions—Automated Monitoring of Mass

Concentrations of Particles: Performance

Characteristics, Test Procedures, and

Specifications,’’ dated 1995, American

National Standards Institute, New York City.

6. G. Box, W. Hunter, J. Hunter, Statistics

for Experimenters (Wiley, New York, 1978).

7. M. Spiegel, Mathematical Handbook of

Formulas and Tables (McGraw-Hill, New

York, 1968).

18.0 Reference Tables, Example

Calculations, Diagrams, Flowcharts, and

Validation Data.

18.1 Reference Tables

TABLE I: FACTORS FOR CALCULATION OF CONFIDENCE AND TOLERANCE INTERVALS

f tn–2 vn–2 n’ un’(75)

7 ........................................................................................................................................................................ 2.365 1.7972 7 1.233
67814 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

TABLE I: FACTORS FOR CALCULATION OF CONFIDENCE AND TOLERANCE INTERVALS—Continued

f tn–2 vn–2 n’ un’(75)

8 ........................................................................................................................................................................ 2.306 1.7110 8 1.223

9 ........................................................................................................................................................................ 2.262 1.6452 9 1.214

10 ...................................................................................................................................................................... 2.228 1.5931 10 1.208

11 ...................................................................................................................................................................... 2.201 1.5506 11 1.203

12 ...................................................................................................................................................................... 2.179 1.5153 12 1.199

13 ...................................................................................................................................................................... 2.160 1.4854 13 1.195

14 ...................................................................................................................................................................... 2.145 1.4597 14 1.192

15 ...................................................................................................................................................................... 2.131 1.4373 15 1.189

16 ...................................................................................................................................................................... 2.120 1.4176 16 1.187

17 ...................................................................................................................................................................... 2.110 1.4001 17 1.185

18 ...................................................................................................................................................................... 2.101 1.3845 18 1.183

19 ...................................................................................................................................................................... 2.093 1.3704 19 1.181

20 ...................................................................................................................................................................... 2.086 1.3576 20 1.179

21 ...................................................................................................................................................................... 2.080 1.3460 21 1.178

22 ...................................................................................................................................................................... 2.074 1.3353 22 1.177

23 ...................................................................................................................................................................... 2.069 1.3255 23 1.175

24 ...................................................................................................................................................................... 2.064 1.3165 24 1.174

25 ...................................................................................................................................................................... 2.060 1.3081 25 1.173

30 ...................................................................................................................................................................... 2.042 1.2737 30 1.170

35 ...................................................................................................................................................................... 2.030 1.2482 35 1.167

40 ...................................................................................................................................................................... 2.021 1.2284 40 1.165

45 ...................................................................................................................................................................... 2.014 1.2125 45 1.163

50 ...................................................................................................................................................................... 2.009 1.1993 50 1.162

TABLE II: VALUES FOR Ff.

f Ff f Ff

1 ............................................................................................................................................................................ 161.4 16 4.49

2 ............................................................................................................................................................................ 18.51 17 4.45

3 ............................................................................................................................................................................ 10.13 18 4.41

4 ............................................................................................................................................................................ 7.71 19 4.38

5 ............................................................................................................................................................................ 6.61 20 4.35

6 ............................................................................................................................................................................ 5.99 22 4.30

7 ............................................................................................................................................................................ 5.59 24 4.26

8 ............................................................................................................................................................................ 5.32 26 4.23

9 ............................................................................................................................................................................ 5.12 28 4.20

10 .......................................................................................................................................................................... 4.96 30 4.17

11 .......................................................................................................................................................................... 4.84 40 4.08

12 .......................................................................................................................................................................... 4.75 50 4.03

13 .......................................................................................................................................................................... 4.67 60 4.00

14 .......................................................................................................................................................................... 4.60 80 3.96

15 .......................................................................................................................................................................... 4.54 100 3.94

TABLE III: FIELD TEST DATA FOR CALIBRATION

Run No.

(mg/Acm) Date

CEMS PM response

(arbitrary

units)

M 5 Conc.

(mg/dscm)

ave Ts

(°F) Bws Abs P(in Hg) O2 M5 Conc

1 ..................... ....................... ....................... ....................... ....................... ....................... ....................... ....................... ................

2 ..................... ....................... ....................... ....................... ....................... ....................... ....................... ....................... ................

3 ..................... ....................... ....................... ....................... ....................... ....................... ....................... ....................... ................

4 ..................... ....................... ....................... ....................... ....................... ....................... ....................... ....................... ................

5 ..................... ....................... ....................... ....................... ....................... ....................... ....................... ....................... ................

6 ..................... ....................... ....................... ....................... ....................... ....................... ....................... ....................... ................

18.2 Example Calculations

18.2.1 Method 5 concentrations conversions

Example (a): CEMS measurement conditions were made at actual stack conditions, requiring that the Method 5 concentration

must be converted from dry standard to actual stack conditions.

where:

C= Concentration at actual stack conditions (mg/Acm): is unknown

Cs= 38.66 mg/dscm

ts= 291.7°F

P = 30.13 in Hg

O2=Assumed to be 11.63% O2

Bws= .226
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67815

C mg dscm R

F

inHg

inHg = °+ ° ( . / ) − ( . )

.

. 38 66 ( . ) 528460 291 7

30 13

29 92

1 226

C = 21.17 mg/Acm

Example (b) CEMS measurement

conditions were made at the dry standard

condition. Convert the concentration to units

of the emission regulation (dry standard

conditions at 7% O2).

where:

C s@7%= Concentration at standard

conditions @ 7% O2; is unknown

O2=Assumed to be 11.63% O2

C mg dscm O s@ . / ( . )

( . ) 7%

2

38 66 20 9 7

20 9 = −−

C s @7%=57.97 mg/dscm @ 7% O2

Example (c): The emission regulation (dry

standard conditions at 7% O2) must be

converted to actual stack conditions.

Using the Proposed Emission Limit: 50 mg/

dscm @ 7% O2

where:

C s @7%= 50 mg/dscm @ 7% O2

ts = 291.4°F, average temperature during

initial calibration

Bws = .201, average moisture during initial

calibration

P = 30.08, average absolute stack pressure

during initial calibration

C C R

inHg @ @s ( .4)

.

. ( . ) 7% 7%

528

460 291

30 08

29 92 = ( ) 1 201 °+ −

O2=Assumed to be 11.63% O2 C @7%= 28.22 mg/Acm 7% O2

C mg Acm O = −

− 28 22 7% 20 920 9 7

2 . / @ .

( . )

C=18.82 mg/Acm

Example (d) The following table is the data

set of a representative monitor and its initial

calibration. These CEMS measurement

conditions are at actual stack conditions. X

is the CEMS arbitrary unit measurements and

Y is the corresponding Method 5

concentration at actual stack conditions.

Run x y

1 ............................................ 18.48 10.93

2 ............................................ 21.85 11.19

3 ............................................ 27.10 13.80

4 ............................................ 31.54 16.70

5 ............................................ 32.33 16.61

6 ............................................ 8.35 2.64

7 ............................................ 15.83 6.65

8 ............................................ 11.95 6.01

9 ............................................ 8.43 3.02

Run x y

10 .......................................... 9.59 4.15

11 .......................................... 13.81 7.31

12 .......................................... 21.48 11.93

13 .......................................... 27.64 11.27

14 .......................................... 7.08 3.11

15 .......................................... 6.15 2.21

16 .......................................... 8.92 5.50

17 .......................................... 8.77 3.59

18 .......................................... 17.10 6.96

19 .......................................... 13.58 5.33

20 .......................................... 14.14 6.70

21 .......................................... 15.28 6.59

22 .......................................... 13.92 7.00

23 .......................................... 14.00 6.52

24 .......................................... 15.09 4.76

25 .......................................... 17.43 9.78

26 .......................................... 21.63 10.22

27 .......................................... 18.56 10.83

Run x y

28 .......................................... 48.53 18.81

29 .......................................... 82.25 29.01

30 .......................................... 83.04 28.88

31 .......................................... 21.20 8.98

32 .......................................... 60.00 22.38

33 .......................................... 32.08 15.94

34 .......................................... 43.05 20.19

35 .......................................... 30.51 13.77

36 .......................................... 12.45 3.84

where:

Sxx = 12338.81

Syy = 1690.99

Sxy = 4410.24

xlave = 23.699

ylave = 10.365

SL = 1.836

y x ˆ = ⋅ + 0 357 1894 . .

From equations 7,8, and 9, the line

regression is

Correlation coefficient

From equation 16, the correlation

coefficient is 0.966

Confidence interval

Using the Proposed Emission Limit: 50 mg/

dscm @ 7% O2 converted to actual conditions

in example (c) C=18.82 mg/Acm. Calculate

CEMS response (x) using line regression

calculated above.

where:

tf = 2.032

y y t s

n

x x

S c f L with f n

xx

= ± ⋅ + − ˆ = − ( ) , 1 2

2
67816 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

=18.82 mg/Acm±1.0

Tolerance interval

where:

n’ = 13

vf = 1.253

kT = 1.498

y y k s T T L = ± ⋅ ˆ

18.3 Diagrams [Reserved]

YT=18.82 mg/Acm±2.75

18.4 Flowcharts [Reserved]

18.5 Validation Data [Reserved]

Appendix III—Procedure 2

Procedure 2. Quality Assurance

Requirements for Particulate Matter

Continuous Emission Monitoring Systems

Used for Compliance Determination

1. Applicability and Principal

1.1 Applicability. Procedure 2 is used to

evaluate the effectiveness of quality control

(QC) and quality assurance (QA) procedures

and the quality of data produced by any

particulate matter (PM) continuous emission

monitoring system (CEMS) that is used for

determining compliance with the emission

standards on a continuous basis as specified

in the applicable regulation. The CEMS may

include diluent (e.g., O2) monitors and other

auxiliary monitoring equipment for

measurement, determination, or input of the

gas temperature, pressure, moisture content,

or sample volume .

This procedure specifies the minimum QA

requirements necessary for the control and

assessment of the quality of CEMS data

submitted to the Environmental Protection

Agency (EPA). Source owners and operators

responsible for one or more CEMS’s used for

compliance monitoring must meet these

minimum requirements and are encouraged

to develop and implement a more extensive

QA program or to continue such programs

where they already exist.

Data collected as a result of QA and QC

measures required in this procedure are to be

submitted to the Agency. These data are to

be used by both the Agency and the CEMS

operator in assessing the effectiveness of the

CEMS QC and QA procedures in the

maintenance of acceptable CEMS operation

and valid emission data.

Appendix F, Procedure 2 applicability and

the CEMS accuracy assessments are

determined by individual regulations.

1.2 Principal. The QA procedure consist

of two distinct and equally important

functions. One function is the assessment of

the quality of the CEMS data by estimating

accuracy. The other function is the control

and improvement of the quality of the CEMS

data by implementing QC policies and

corrective actions. These two functions form

a control loop: When the assessment function

indicates that the data quality is inadequate,

the control effort must be increased until the

data quality is acceptable. In order to provide

uniformity in the assessment and reporting of

data quality, this procedure explicitly

specifies the assessment methods for

response drift and accuracy. The methods are

based on procedures included in the

applicable performance specifications (PS’s)

in general, and are specifically applicable to

PS 11, in appendix B of 40 CFR part 60.

Procedure 2 also requires CEMS

measurements of samples concurrent with

reference method (RM) measurements.

Because the control and corrective action

function encompasses a variety of policies,

specifications, standards, and corrective

measures, this procedure treats QC

requirements in general terms to allow each

source owner or operator to develop a QC

system that is most effective and efficient for

the circumstances.

2. Definitions

2.1 Continuous Emissions Monitoring

System means the total equipment required

for the determination of a particulate matter

mass concentration in units of the emission

standard. The sample interface, pollutant

analyzer, diluent analyzer, other auxiliary

data monitor(s) and data recorder are the

major subsystems of the CEMS.

2.2 Calibration Drift (CD) means the

difference in the CEMS output readings from

the established reference value after a stated

period of operation during which no

unscheduled maintenance, repair, or

adjustment took place.

2.3 Calibration relation means the

relationship between a CEMS response and

measured PM concentrations by the reference

method which is defined by a mathematical

equation.

2.4 Calibration Standard means a

reference material that produces a known

and unchanging response when presented to

the pollutant analyzer portion of the CEMS,

and used to calibrate the drift or response of

the analyzer.

2.5 Flagged data means data marked by

the CEMS indicating that the response value

is suspect or invalid.

2.6 Span Value means the upper limit of

the CEMS measurement range. The span

value shall be documented by the CEMS

manufacturer with laboratory data.

2.7 Zero Drift (ZD) means the difference

in the CEMS output readings for zero input

after a stated period of operation during

which no unscheduled maintenance, repair,

or adjustment took place.

3. QC Requirements

Each source owner or operator must

develop and implement a QC program. As a

minimum, each QC program must include

written procedures which should describe in

detail, complete, step-by-step procedures and

operations for each of the following

activities:

1. Internal-Calibration of CEMS relative to

assessing CD.

2. CD determination and adjustment of

CEMS.

3. Preventative maintenance of CEMS

(including spare parts inventory and

sampling probe integrity).

4. Data recording, calculations, and

reporting.

5. Accuracy audit procedures including

sampling and analysis methods, sampling

strategy, and structuring test conditions over

the prescribed range of PM concentrations.

6. Program of corrective action for

malfunctioning CEMS, including flagged data

periods.

As described in Section 5.2, whenever

excessive inaccuracies occur, the source

owner or operator must revise the current

written procedures or modify or replace the

CEMS to correct the deficiency causing the

excessive inaccuracies.

These written procedures must be kept on

record and available for inspection by the

enforcement agency.

4. CD Assessment

4.1 CD Requirement. As described in 40

CFR 60.13(d), source owners and operators of

CEMS must check, record, and quantify the

CD at two concentration values at least daily

(approximately 24 hours) in accordance with

the method prescribed by the manufacturer.

The CEMS calibration must, as minimum, be

adjusted whenever the daily zero drift or the

daily span value exceeds two times the limits

of PS 11 in appendix B of this regulation.

4.2 Recording Requirement for Automatic

CD Adjusting Monitors. Monitors that

automatically adjust the instrument

responses to the corrected calibration values

(e.g., microprocessor control) must be

programmed to record the unadjusted

concentration measured in the CD prior to

resetting the calibration, if performed, or

record the amount of adjustment.

4.3 Criteria for Excessive CD. If either the

zero drift or the daily span value exceeds

twice the PS 11 drift specification for five,

consecutive, daily periods, the CEMS is outof-control. If either the zero drift or the daily

span value exceeds four times the PS 11 drift

specification during any CD check, the CEMS

is out-of-control. If the CEMS is out-ofcontrol, take necessary corrective action.

Following corrective action, repeat the CD

checks.

4.3.1 Out-Of-Control Period Definition.

The beginning of the out-of-control period is

the time corresponding to the completion of

the fifth, consecutive, daily CD check with a

CD in excess of two times the allowable limit,

or the time corresponding to the completion

of the daily CD check that results in a CD in

excess of four times the allowable limit. The

end of the out-of-control period is the time

corresponding to the completion of the CD

check following corrective action that results

in the CD’s at both the zero or the daily span

value points being within the corresponding

allowable CD limit (i.e., either two times or

four times the allowable limit in appendix B).

4.3.2 CEMS Data Status During Out-OfControl Period. During the period the CEMS

is out-of-control, the CEMS data may not be

used in calculating emission compliance nor

be counted towards meeting minimum data

availability as required and described in the

applicable subpart [e.g., 60.47a(f)].

4.4 Data Recording and Reporting. As

required in 60.7(d) of this regulation (40 CFR

part 60), all measurements from the CEMS

must be retained on file by the source owner

for at least 2 years. However emission data

obtained on each successive day while the

CEMS is out-of-control may not be included

as part of the minimum daily requirement of

the applicable subpart [e.g., 60.47a(f)] nor be

used in the calculation of reported emissions

for that period.
Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules 67817

5. Data Accuracy Assessment

5.1 Auditing Requirements. Each CEMS

must be audited at least once each calender

quarter. Successive quarterly audits shall

occur no closer than 2 months. The audits

shall be conducted as follows:

5.1.1 Response Calibration Audit (RCA).

The RCA must be conducted at the frequency

specified in the applicable regulation.

Conduct the RCA test according to the

sampling strategy described in Section 8.4.3

and according to the structure of test

described in Section 8.4.5, both of which are

in PS 11 in appendix B, except that the

minimum of runs required shall be 12 in the

RCA instead of 15 as specified in PS 11. If

it is not possible/practical to obtain three

measured data points in all three PM

concentration ranges as specified in Section

8.4.5 of PS 11, a minimum of three measured

data points in any of the two ranges specified

in Section 8.4.5 is acceptable, as long as at

least all 12 data points lie within the range

of the calibration relation test.

5.1.2 Absolute Calibration Audit (ACA).

If applicable, an ACA shall be conducted

each quarter except in the quarters when a

RCA is conducted.

To conduct an ACA: (1) Challenge the

CEMS with an audit standard or an

equivalent audit reference to reproduce the

monitor’s measurement at three points

within the following ranges:

Audit point Audit range

1 ......................... 0 to 20% of span value.

2 ......................... 40 to 60% of span value

and.

3 ......................... 80 to 100% of span

value.

Challenge the CEMS three times at each

audit point, and use the average of the three

responses in determining accuracy.

Use a separate audit standard or an

equivalent audit reference for audit points 1,

2, and 3.

The monitor should be challenged at each

audit point for a sufficient period of time to

assure that the CEMS response has stabilized.

(2) Operate each monitor in the mode,

manner and range specified by the

manufacturer.

(3) Use only audit standards or equivalent

audit references specified and provided by

the manufacturer. Store, maintain, and use

audit standards or equivalent audit

references as specified by the manufacturer.

When National Institute of Standards and

Testing (NIST)-traceable audit standards

become available for PM CEMS, their use

will be required.

The difference between the actual known

value of the audit standard or equivalent

audit reference specified by the manufacturer

and the response of the monitor is used to

assess the accuracy of the CEMS.

5.1.3 Relative Accuracy Audit (RAA)

[Reserved].

5.1.4 Sample Volume Audit (SVA). For

applicable units with a sampling system, an

audit of the equipment to determine sample

volume (e.g., equipment measuring sampling

flowrate for a known time) must be

performed once a year. The SVA procedure

specified by the manufacturer will be

followed to assure that sample volume is

accurately measured across the normal range

of sample volumes made over the past year.

5.1.5 Other Alternative Audits. Other

alternative audit procedures may be used as

approved by the Administrator for the

quarters when ACAs are to be conducted.

5.2 Excessive Audit Inaccuracy. If the

audit results using the RCA, ACA, RAA, or

SVA, do not meet the criteria in Section

5.2.3, the CEMS is out-of-control. If the

CEMS is out-of-control, take necessary

corrective action to eliminate the problem.

Following corrective action, the source

owner or operator must audit the CEMS with

a calibration relation test, ACA, RAA, or SVA

to determine if the CEMS is operating within

the specifications. A calibration relation test

must always be used following an out-ofcontrol period resulting from a RCA. If audit

results show the CEMS to be out-of-control,

the CEMS operator shall report both the audit

showing the CEMS to be out-of-control and

the results of the audit following corrective

action showing the CEMS to be operating

within specifications.

5.2.1 Out-Of-Control Period Definitions.

The beginning of the out-of-control period is

the time corresponding to the completion of

an unsuccessful RCA, ACA, RAA, or SVA.

The end of the out-of-control period is the

time corresponding to the completion of the

subsequent successful calibration test or

audit.

5.2.2 CEMS Data Status During Out-OfControl Period. During the period the

monitor is out-of-control, the CEMS data may

not be used in calculating emission

compliance nor be counted towards meeting

minimum data availability as required and

described in the applicable subpart.

5.2.3 Criteria for Excessive Audit

Inaccuracy. Unless specified otherwise in the

applicable subpart, the criteria for excessive

inaccuracy are:

(1) For the RCA, at least 75% of a

minimum number of 12 sets of CEMS/

reference method measurements from the test

must fall within a specified area on a graph

developed by the calibration relation

regression line over the calibration range and

the tolerance interval set at +/-25% of the

emission limit. The specified area on a graph

is (a) bounded by two lines parallel with the

calibration regression line, and offset at a

distance +/-25% of the numerical emission

limit from the calibration regression line on

the y-axis, and (b) traversing across the

calibration range bounded by the lowest and

the highest CEMS reading of the calibration

test on the x-axis.

(2) For the ACA, +/-15 percent of the

average audit value or 7.5% of the applicable

standard, whichever is greater.

(3) For the SVA, +/-5 percent of the average

sample volume audit value .

5.3 Criteria For Acceptable QC Procedure.

Repeated excessive inaccuracies (i.e., out-ofcontrol conditions resulting from the

quarterly audits) indicates the QC procedures

are inadequate or that the CEMS is incapable

of providing quality data. Therefore,

whenever excessive inaccuracies occur for

two consecutive quarters, the source owner

or operator must revise the QC procedures

(see Section 3) or modify or replace the

CEMS.

6. Calculations for CEMS Data Accuracy and

Acceptability Determination

6.1 RCA Calculations and Determination

of Acceptability.

6.1.1 RCA Calculations. Follow the

equations described in Section 12 of

appendix B, PS 11 to calculate results from

the RCA tests. The reference method results

from the RCA must be calculated in units

consistent with the CEMS measurement

approach in use (e.g., mg/m3 or mg/dscm).

6.1.2 Acceptability Determination of RCA

Data. Plot each of the CEMS/reference

method data from the RCA test on a figure

based on the calibration relation regression

line to determine if the appropriate criterion

in Section 5.2.3 (1) is met.

6.2 ACA Accuracy Calculation. Use

Equations 1 and 2 to calculate results from

the ACA tests.

A

R R

R

CEM V

V

= ( ) − ×100 1 , ( -1)

where:

A = Accuracy of the CEMS, percent.

RCEM = Average CEMS response during

audit.

RV = Reference value of the audit

calibration standard or the equivalent audit.

A

R R

R

CEM V

EM

= ( ) − ×100 12 , ( ) -

where:

A = Accuracy of the CEMS, percent.

RCEM = Average CEMS response.

RV = Reference value of the audit

calibration standard or the equivalent audit.

REM = the emission limit value.

6.3 SVA Accuracy Calculation. The

appropriate SVA calculations will be

provided by the CEMS manufacturer.

6.4 Treatment of Flagged Data. All flagged

CEMS data are considered invalid; as such,

these data may not be used in determining

compliance nor be counted towards meeting

minimum data availability as required and

described in the applicable subpart.

6.5 Alternative Calibration Relation

Approaches. Certain PM CEMS have

technologies established on principles

measuring PM concentration directly,

whereas other technologies measure PM

properties indirectly indicative of PM

concentration. It has been shown empirically

that a linear relationship can exist between

these properties and PM concentration over

a narrow range of concentrations, provided

all variables remain essentially constant.

However, if all variables affecting this

relationship do not remain constant, then a

linear relationship will probably not occur.

Such is the case expected for facilities with

PM emissions over a wide range of PM

concentrations with certain process and air

pollution control configurations. Other nonlinear relations may provide a better fit to the

calibration data than linear relations because

the monitor’s response is based on some

measurable, and changing, property of the

PM concentrations. These non-linear
67818 Federal Register / Vol. 62, No. 249 / Tuesday, December 30, 1997 / Proposed Rules

approaches may serve as improved

approaches for defining the mathematical

relation between the CEMS response and

reference method measured PM

concentrations. The basis and advantage for

developing and implementing such

alternative approaches for determining

compliance must be explicitly included in

the calibration relation test report with

supporting data demonstrating a better fit

than a linear relation. Use of these alternative

approaches is subject to approval by the

Administrator.

6.6 Example Accuracy Calculation.

Example calculations and illustration for the

RCA are available in Citation 1. Example

calculations for the ACA are available in

Citation 3 of Appendix F—Procedure 1 and

will be available in Citation 2.

7. Reporting Requirements

At the reporting interval specified in the

applicable regulation, report for each CEMS

the accuracy results from Section 6 and the

CD assessment results from Section 4. Report

the drift and accuracy information as a Data

Assessment Report (DAR), and include one

copy of this DAR for each quarterly audit

with the report of emissions required under

the applicable subparts of this part.

As a minimum, the DAR must contain the

following information:

1. Source owner or operator name and

address

2. Identification and location of monitors

in the CEMS.

3. Manufacturer and model number of each

monitor in the CEMS.

4. Assessment of CEMS data accuracy/

acceptability and date of assessment as

determined by a RCA, ACA, RAA, or SVA

described in Section 5 including the

acceptability determination for the RCA, the

A for the ACA or RAA or SVA, the RM

results, the calibration audit standards or

equivalent audit references, the CEMS

responses, and the calculation results as

defined in Section 6. If the accuracy audit

results show the CEMS to be out-of-control,

the CEMS operator shall report both the audit

results showing the CEMS to be out-ofcontrol and the results of the audit following

corrective action showing the CEMS to be

operating within specifications.

5. Summary of all corrective actions taken

when CEMS was determined out-of-control,

as described in Sections 4 and 5.

An example of a DAR format will be shown

later in Figure 1.

8. Bibliography

To Be Determined

Figure 1—Example Format For Data

Assessment Report: To Be Determined

[FR Doc. 97–33740 Filed 12–29–97; 8:45 am]

BILLING CODE 6560–50–P

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Parts 85 and 89

[AMS—FRL–5939–6 ]

Control of Air Pollution: Emission

Standards for New Nonroad

Compression-Ignition Engines at or

Above 37 Kilowatts; Preemption of

State Regulation for Nonroad Engine

and Vehicle Standards; Amendments

to Rules

AGENCY: Environmental Protection

Agency.

ACTION: Notice of proposed rulemaking.

SUMMARY: Today’s action, consistent

with an order and opinion from the U.S.

Court of Appeals for the District of

Columbia Circuit, proposes

amendments to EPA’s regulations

setting emission standards for large (at

or above 37 kilowatts) nonroad

compression ignition engines and to

EPA’s regulations defining the scope of

preemption of state and local nonroad

emission standards and establishing

procedures for EPA authorization of

California nonroad emission standards.

Specifically, EPA proposes to withdraw

portions of an interpretive rule which

set forth the Agency’s position on the

Clean Air Act regarding the status of

certain internal combustion engines

manufactured before the effective date

of the final rulemaking promulgating

EPA’s definition of nonroad engine.

Additionally, consistent with the DC

Circuit opinion, EPA also is amending

the remaining text of this interpretive

rule, as well as EPA’s regulations issued

under section 209(e) of the Act

regarding the Agency’s California

nonroad standards authorization

process, to clarify that California must

seek authorization from EPA prior to

enforcing standards and other

requirements relating to emissions from

any nonroad vehicles or engines, and

not just new nonroad vehicles and

engines, which was the original

language used in these regulations.

In the final rule section of today’s

Federal Register, EPA is issuing these

amendments as a direct final rule

without prior proposal, because EPA

views the action as noncontroversial

and anticipates no adverse comments. A

detailed rationale for the amendments

and for the decision to issue them as a

direct final rule is set forth in the

Preamble to the direct final rules. If no

adverse comments are received in

response to the direct final rule, no

further activity is contemplated in

relation to this proposed rule. If EPA

receives adverse comments, the direct

final rule will be withdrawn, and all

public comments received will be

addressed in a subsequent final rule

based on this proposed rule.

Additionally, EPA will hold a public

hearing on this proposed rule if one is

requested.

DATES: Any party who wishes to submit

comments must do so by March 2, 1998

unless a hearing is requested. Any party

can request EPA to hold a public

hearing on this action, but such request

must be received by January 29, 1998.

If a hearing is requested, it will take

place on March 2, 1998, and interested

parties will have an additional 30 days

after the hearing (until March 30, 1998)

to submit comments on any information

presented at the hearing. Because no

hearing will occur absent a request for

one, interested parties should contact

Robert M. Doyle at the number listed

below after January 29, 1998 to

determine whether a hearing will take

place.

ADDRESSES: Written comments should

be submitted (in duplicate if possible)

to: Air Docket Section (6102), Attention:

Docket No. A–91–24, U.S.

Environmental Protection Agency, 401

M Street, SW, Washington, DC 20460, or

hand-delivered to the Air Docket at the

above address, in Room M–1500,

Waterside Mall. A copy of written

comments should also be submitted to

Robert M. Doyle at the address below.

FOR FURTHER INFORMATION CONTACT:

Robert M. Doyle, Attorney/Advisor,

Engine Programs and Compliance

Division (6403J), U.S. Environmental

Protection Agency, 401 M. Street, SW,

Washington, DC 20560, (202) 564–9258,

FAX (202) 233–9596, E-Mail,

Doyle.Robert@EPAMAIL.EPA.GOV.

SUPPLEMENTARY INFORMATION: For

additional information, please see the

direct final rule published in the rules

section of today’s Federal Register.

List of Subjects

40 CFR Part 85

Environmental protection,

Administrative practice and procedure,

Air pollution control, Federal

preemption, Motor vehicle pollution,

Nonroad engine and vehicle pollution,

Reporting and recordkeeping

requirements, State controls.

40 CFR Part 89

Environmental protection,

Administrative practice and procedure,

Air pollution control, Confidential

business information, Imports,

Incorporation by reference, Labeling,

Nonroad source pollution, Reporting

and recordkeeping requirements.