Federal Register / Vol. 63, No. 98 /Thursday, May 21, 1998 / Proposed Rules 28195

B to this part. Follow the reporting

provisions of §§ 75.60 through 75.67.

77. Appendix J to part 75 is removed

and reserved.

[FR Doc. 98–11749 Filed 5–20–98; 8:45 am]

BILLING CODE 6560–50–P

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 75

[FRL–6007–7]

RIN 2060–AH64

Acid Rain Program: Determinations

under EPA Study of Bias Test and

Relative Accuracy and Availability

Analysis

AGENCY: Environmental Protection

Agency (EPA).

ACTION: Notice of proposed

determinations and proposed

rulemakings.

SUMMARY: Title IV of the Clean Air Act

Amendments of 1990 (the Act)

authorizes EPA to establish a program to

reduce the adverse effects of acidic

deposition. The Act requires electric

utilities affected by the Acid Rain

Program to install continuous emission

monitoring systems (CEMS) to measure

emissions of sulfur dioxide (SO2),

nitrogen oxides (NOX), and carbon

dioxide (CO2). On January 11, 1993,

Continuous Emission Monitoring

regulations were published. They

established procedures and

requirements for installing, certifying,

operating, and quality assuring CEMS at

Acid Rain affected utility units. In

response to comments and litigation

from representatives of the electric

utility industry and environmental

advocacy groups, provisions were

incorporated in the CEMS regulations

requiring EPA to conduct studies, reach

determinations, and, if necessary,

initiate rulemakings on the

appropriateness of retaining or revising

three elements in the CEMS regulations:

the bias test, relative accuracy test, and

the availability trigger conditions of the

Missing Data Substitution Procedure.

This Notice of Proposed Rulemaking

presents EPA’s proposed determinations

and consequent proposed rule revisions.

DATES: Comments. Comments on the

proposed determinations and rule

revisions must be received on or before

July 6, 1998.

Public Hearing. Anyone requiring a

public hearing must contact EPA no

later than June 1, 1998. If a hearing is

held, it will take place June 5, 1998,

beginning at 10:00 a.m.

ADDRESSES: Comments. All written

comment must be identified with the

appropriate docket number (Docket No.

A–97–56) and must be submitted in

duplicate to EPA Air Docket Section

(6102), Waterside Mall, Room M1500,

1st Floor, 401 M Street, SW,

Washington, D.C. 20460.

Public Hearing. If a public hearing is

requested, it will be held at the

Environmental Protection Agency, 401

M Street, SW, Washington, D.C. 20460,

in the Education Center Auditorium.

Refer to the Acid Rain homepage at

www.epa.gov/acidrain for more

information or to determine if a public

hearing has been requested and will be

held.

Docket. Docket No. A–97–56,

containing supporting information used

to develop the proposed determinations

and rule revisions is available for public

inspection and copying from 8:00 a.m.

to 5:30 p.m., Monday through Friday,

excluding legal holidays, at EPA’s Air

Docket Section at the above address.

FOR FURTHER INFORMATION CONTACT:

Elliot Lieberman at (202) 564 9136, Acid

Rain Division (6204J), U.S.

Environmental Protection Agency, 401

M St., S.W., Washington, D.C. 20460; or

the Acid Rain Hotline at (202) 564 9620.

Electronic copies of this notice and

technical support documents can be

accessed through the Acid Rain Division

website at http://www.epa.gov/acidrain.

SUPPLEMENTARY INFORMATION:

I. EPA Studies Under 40 CFR 75.7

A. Background

B. Collaborative Field Study

C. Certification Test Study

D. Proposed Findings and Conclusions

II. EPA Analyses in Response to 40 CFR 75.8

A. Background

B. Relative Accuracy

C. Availability Trigger Conditions for

Missing Data Substitution Procedure

III. Proposed Rule Revisions

IV. Administrative Requirements

A. Executive Order 12866

B. Unfunded Mandates Act

C. Paperwork Reduction Act

D. Regulatory Flexibility

I. EPA Studies Under 40 CFR 75.7

A. Background

To ensure a consistent level of

precision and accuracy in the emission

measurements obtained across the Acid

Rain Program, Part 75 of the Acid Rain

regulations requires a series of

performance tests to be conducted on

each CEMS both at initial certification

and periodically thereafter. Among the

required performance tests is the

relative accuracy test audit (RATA) in

which a minimum of nine simultaneous

measurements are taken from a unit’s

installed CEMS and an EPA approved

reference method. The paired RATA

data are then subjected to two statistical

tests: The relative accuracy test, which

establishes the degree of accuracy of the

CEMS relative to the reference method;

and the bias test, which uses a t-statistic

to determine if the CEMS measurements

are consistently lower than the reference

method measurements. See 40 CFR Part

75, Appendix A and B.

As stated in the preamble of the

January 1993 regulations, EPA found

that ‘‘both statistical theory and field

test results show that the bias test is a

sound and effective statistical procedure

for detecting consistent measurement

error in the long-term operation of a

CEMS’’ (58 FR 3590, 3627 (1993)).

However, at the time of promulgation of

the Acid Rain regulations, although

utilities had extensive experience with

the relative accuracy test, they had

virtually no previous experience with

the bias test. This unfamiliarity led to

several concerns with the bias test.

Thus, the January 1993 regulations

committed EPA to conduct field studies

to determine ‘‘whether there are

statistically significant variances’’ in the

EPA-approved reference methods that

utilities use to test the performance of

the CEMS installed under the Acid Rain

Program and ‘‘whether the bias test

should be adjusted to compensate for

statistical variances in the reference

method’’ (58 FR 3628).

In particular, EPA was required to:

1. Investigate whether there are

statistically significant variances in the

EPA reference methods (Issue #1);

2. Distinguish between the variability

in reference monitor readings

attributable to measurement error and

the variability due to the choice of

reference monitor among those certified

by the Agency (Issue #2);

3. Investigate possible differences in

bias test failure rates by emission levels

(Issue #3); and

4. Assess whether any adjustments are

necessary to properly determine

measurement bias (Issue #4).

The regulations called for the

completion of a study addressing these

issues by October 31, 1993. In response,

EPA conducted two studies. The first

was a collaborative field study,

involving four independent reference

method test teams, at Big Rivers Electric

Corporation’s Green Generating Station,

Unit 2, in Sebree, Kentucky. This

location was specifically selected for

testing because its relatively low range

of SO2 emission concentrations (from 56

ppm to 231 ppm) would allow EPA to

examine bias test failure rates at SO2

emission levels different from those

prevailing in previous field studies and

consider an industry concern that
28196 Federal Register / Vol. 63, No. 98 /Thursday, May 21, 1998 / Proposed Rules

contradictory bias test results were more

likely to occur at low, than at high,

emission concentrations. Field work for

this study was completed from August

16–31, 1993. Separate data summary

(Docket Item, A–97–56, II–A–1) and

statistical analyses reports summary

(Docket Item, A–97–56, II–A–2) were

completed in March 1994 and

September 1996 respectively.

The second study involved collection

and analysis of bias test results from the

field tests conducted by affected units

under Part 75 for certification of their

CEMS. The certification test data,

including the bias test, were submitted

to EPA from November 1993 to

September 1996. The study results

reported here (and contained in Docket

Item, A–97–56, II–A–3) were available

in 1997 only after the CEMS at the

majority of both Phase I and Phase II

(lower emitting) units had been received

and certified by EPA.

B. Collaborative Field Study

In the collaborative field study at Unit

2 of Big Rivers Electric Corporation’s

Green Generating Station (‘‘Green Unit

2’’), four labs (i.e., test teams)

simultaneously performed Reference

Methods 6C (for SO2), 7E (for NOX), and

3A (for CO2). To test the two general

monitoring technologies available for

performing the reference methods, two

of the teams used ‘‘wet-basis’’ sampling

techniques and two used ‘‘dry-basis’’

techniques. In the ‘‘wet-basis’’ sampling

techniques, a dilution probe is used to

extract a diluted sample of the effluent

from the stack gas. The diluted gas

sample is then analyzed using an

ambient-level analyzer (e.g., pulsed

fluorescence for SO2,

chemiluminescence for NOX, and

infrared absorption for CO2), which does

not require removal of moisture from

the gas sample. In the ‘‘dry-basis’’

sampling techniques, a gas sample is

extracted from the effluent stream

without dilution. Moisture is condensed

from the gas sample and the resulting

dry sample is then analyzed using a

source-level analyzer (infrared or

ultraviolet for SO2, chemiluminescence

for NOX, and infrared for CO2).

Seventy-two runs of usable data (out

of 76 total runs) were collected by the

four labs. Concurrent measurements

were also collected from Green Unit 2’s

SO2, NOX, and CO2 continuous

emissions monitoring systems,

previously certified under the Acid Rain

Program. On 36 of the runs, each lab

and the unit’s CEMS used separate

calibration gases as required under 40

CFR Part 75. On the other 36 runs, all

labs and the plant’s CEMS shared

common gases when calibrating.

Issues #1 and #2 involve evaluation of

the sources of variability inherent in

EPA’s reference methods. In the

consideration of these two issues only

the reference method measurements

were analyzed, not the unit’s CEMS.

Issues #3 and #4 involve a comparison

of the CEMS and the reference method

measurements to determine if bias

(systematic error) is detected in the

CEMS measurement. In the

consideration of these two issues, the

unit’s CEMS measurements were paired

with each of the four lab’s concurrent

reference method measurements. This

produced four sets of concurrent

Relative Accuracy Test Audits (RATA’s)

which could be used in evaluating bias

test result consistency across the four

labs.

To address the first two issues

concerning the sources and extent of

variability inherent in the reference

methods, the collaborative field study

employed an experimental design

(technically known as a ‘‘randomized

complete block design’’) which allowed

the quantification of the relative

variability associated with (i) amonglaboratory variation, (ii) variation

between monitoring technologies (i.e.,

‘‘wet-basis’’ or ‘‘dry-basis’’ sampling

techniques), (iii) the variability

associated with different calibration gas

scenarios (i.e., separate or shared

calibration gases), and (iv) random error.

Applying an analysis of variance

(ANOVA) statistical procedure to the

field study data, EPA found that the

overall variation in the reference

methods, considering all the monitoring

technologies and calibration gas

scenarios, was 2.93%RSD (Relative

Standard Deviation) for SO2, 2.01%RSD

for NOX, and 1.59%RSD for CO2.

Reference method variations below

approximately 3%RSD are consistent

with the findings of an earlier

collaborative field study, reported in

Docket Item, A–97–56, II–A–5, where

variations of 1.4%RSD and 2.9%RSD

were found for SO2 and NOX

respectively. (The variation for CO2 is

not available from the earlier study

since that study did not include CO2

reference method measurements.) Based

on these findings, with respect to Issue

#1 EPA believes that the statistically

significant variances in the EPA

reference methods are small.

The analysis in the most recent

collaborative study also revealed that

the range in the Relative Standard

Deviation due to the choice of reference

method monitor (i.e., different analyzers

using ‘‘wet-basis’’ or ‘‘dry-basis’’

technology) among allowable reference

method technologies was very small

(below 1%RSD) whether the labs used

separate or shared calibration gases.

Consequently, EPA believes with

respect to Issue #2 that the variability

due to the choice of reference method

monitor among those available is very

small.

As noted earlier, Issues #3 and #4

require consideration of simultaneous

measurements by the unit’s CEMS along

with the four test labs. To respond to

Issue #3, concerning the consistency of

the bias test results, the field test data

were analyzed to determine how much

agreement was found among the four

labs as to whether the CEM was biased

or not biased when current provisions of

Part 75 are followed. In particular, the

consistency in bias test results was

evaluated by counting the number of

concurrent RATA’s in which agreement

among the four test teams was 100% (all

four labs agree), 75% (three out of four

labs agree) and 50% (two labs find bias

and two find no bias). For each

pollutant there was never less than 75%

agreement among the test teams when

the reference methods and the installed

CEMS were each calibrated using

independently selected calibration

gases, as is required under 40 CFR Part

75. For NOX and CO2 there was always

100% agreement. For SO2 there was

100% agreement in bias test results in

more than 76% of the concurrent

RATA’s.

These test results lead EPA to believe

that even at a site exhibiting low SO2

emission concentrations, there is a high

degree of consistency in bias test results.

C. Certification Test Study

To respond further to Issue #3, EPA

analyzed the consistency in bias test

results across the universe of affected

units, by conducting a study of the bias

test results for all CEMS for which

certification tests data were submitted

under Part 75 between November 1993

and September 1996. To see how test

results were affected by emission levels,

the pass/fail rates at different

concentrations (SO2) and emission rates

(NOX) were compared for 1023 SO2 and

1293 NOX bias tests submitted under the

Acid Rain Program. This analysis was

not performed on CO2 monitors, because

under Part 75 units are not required to

perform the bias test on their CO2

monitors.

Grouping monitors according to the

average concentration level (for SO2

CEMS) and average emission rate (for

NOX CEMS), reported by the CEMS

during the RATA, the pass/fail rates

were plotted at regular increasing SO2

emission concentration levels and NOX

emission rates. The resulting graphs

revealed that the percentage of passes

and fails remained relatively consistent
Federal Register / Vol. 63, No. 98 /Thursday, May 21, 1998 / Proposed Rules 28197

across concentration and emission rate

categories. For example, for all SO2

monitors, 73% (750 out of a total of

1023 monitors) passed the bias test.

Assigning each tested monitor to one of

fourteen 100 ppm categories, beginning

at 0–100 ppm and ending at above 1300

ppm, showed that the percent of passing

monitors in all but three of the

concentration categories fell between 70

and 90%. The three categories whose

passing rates were outside this range

were 400–500 ppm (56% passing), 600–

700 ppm (69%), and above 1300 ppm

(63%). Thus, there was little or no

apparent correlation between

concentration level and bias test failure

rates.

The graphical analysis for SO2

monitors was confirmed by calculation

of the r-squared value for the data. The

r-squared value is a measure of the

strength of the linear relationship

between two data sets. R-squared can

take on values from zero to one. A high

r-squared value, i.e., closer to 1 than to

0, would suggest that the bias test pass/

fail rate is highly correlated with the

emission concentration level, e.g., that

bias test failure is more likely with low

emission concentration as suggested by

utilities. A low r-squared value, i.e.,

closer to 0 than to 1, would suggest the

absence of correlation between the bias

pass/fail rate and the emission

concentration level. For the plotted SO2

data, the r-squared value was low:

0.0109.

The same graphical and statistical

analysis was performed on the

certification test data submitted for NOX

CEMS. Bias test pass/fail rates for 1293

NOX monitors were divided into sixteen

0.1 lb/mmBTU categories. Considering

all these categories, 67% (866 out of a

total of 1293 monitors) passed the bias

test. A plot of the data by emission

category showed the bias test passing

rate fell between 65% and 85% in all

but of 3 of the 16 NOX emission

categories. The three emission rate

categories whose passing rates were

outside this range were not correlated to

the measured NOX emission rate: 0.1–

0.2 lb/mmBTU (47% passing), 0.4–0.5

lb/mmBTU (59%), and 1.4–1.5 lb/

mmBTU (50%). Again, there was little

or no apparent correlation between bias

test pass/fail rates and emission rate,

and this was confirmed by the statistical

analysis. The r-squared value for the

NOX data was low: 0.1109.

Thus, the graphical and statistical

analysis performed in the certification

test study indicates consistent bias test

results across emission levels.

D. Proposed Findings and Conclusions

Based on the analyses performed to

address Issues #1–3 in the collaborative

and certification field studies, EPA

considered Issue #4, concerning the

necessity and feasibility of adjustments

to the bias test. EPA currently believes

that the small variability in the

reference methods (less than 3%RSD

across all gas scenarios and monitor

technologies) indicates that there is very

low probability that a continuous

emission monitoring system will fail the

bias test for reasons other than the

presence of true measurement bias in

the CEMS. The high level of consistency

in bias test results seems to support this

view.

Based on these studies, EPA proposes

to find that:

1. The variability attributable to

measurement error and to the choice of

reference monitor technology in the

Agency’s approved test methods for

SO2, NOX, and CO2 is low (below 3.0%

Relative Standard Deviation).

2. Differences in measurement

variability among different allowable

reference method technologies are small

(below 1.0% RSD).

3. There is a high occurrence of

consistency in bias test results.

4. There is no evidence that bias test

failure rates are significantly influenced

by emission levels.

Documentation of these proposed

findings can be found in four docket

items: A Collaborative Field Evaluation

of EPA Test Methods 6C, 7E, and 3A

(March 1994) (Docket Item, A–97–56, II–

A–1) gives a detailed description of the

collaborative field test activities, site

characteristics, and equipment

employed, presents data obtained in the

field study, and discusses preliminary

findings on the variability of the

reference methods. A second report, An

Operator’s Guide to Eliminating Bias in

CEM System (November 1994) (Docket

Item, A–97–56, II–A–6) is an

independent technical guidance

document advising environmental

technicians on procedures for detecting

and correcting engineering problems

that could produce measurement bias in

CEM systems. A third report, Statistical

Analysis of Reference Method

Variability and Bias Test Consistency in

the Collaborative Field Study of EPA

Test Methods 6C, 7E, and 3A at Big

Rivers Electric Corporation, Green

Generating Station, Unit 2 (September

1996) ((Docket Item, A–97–56, II–A–2),

focuses on the analysis of the

collaborative study field data, reports

the results of this analysis with respect

to the four issues that the study was

designed to address, and, based on this

analysis, makes recommendations

concerning whether adjustments are

needed to the bias test. Finally, the

graphs and supporting data from the

certification test study can be found in

‘‘Bias Test Pass/Fail Rates at Different

SO2 and NOX Emission Levels as

Reported in Certification Relative

Accuracy Test Audits (RATA’s)

submitted through September 1996

under 40 CFR Part 75.’’ (December 1997)

(Docket Items, A–97–56, II–A–3 and II–

A–4).

Based on the proposed findings

enumerated above, EPA proposes to

determine that adjustments to the

equations in the bias test are technically

unnecessary to properly determine

measurement bias. EPA therefore

proposes not to initiate a rulemaking to

change the bias test under § 75.7.

II. EPA Analyses in Response to 40 CFR

75.8

A. Background

In accordance with a settlement

agreement, signed on April 17, 1995 in

Environmental Defense Fund v.

Browner, No. 93–1203 and consolidated

cases (D.C. Cir., 1993), which addressed

various CEMS issues, § 75.8 was

adopted as part of the direct final rule,

dated May 17, 1995, amending the

January 11, 1993 rule’s CEM provisions.

Section 75.8 required EPA to evaluate

the appropriateness of the current

relative accuracy and availability trigger

conditions for missing data substitution

for SO2, NOX, and CO2 CEMS and flow

monitors. This evaluation was to be

based on initial certification test data

and quarterly report data for the 1993–

1996 period. Using the evaluation, EPA

was to determine whether to retain the

current specifications or propose

alternative performance specifications.

A report evaluating this data was to be

prepared by July 1, 1997, and EPA is to

issue either a notice determining that

the current rule provisions are

appropriate or a notice proposing

revisions. Any proposal revising the

current rule is to be issued by October

31, 1997 and finalized by October 31,

1998. The results of EPA’s evaluations

of the current relative accuracy and

availability trigger conditions are

described below.

B. Relative Accuracy

Relative accuracy is a statistical

indicator of how closely the

measurements by an installed CEM

approximate those obtained by a

concurrently used EPA reference

method during a 9–12 run field

demonstration (known as the relative

accuracy test audit (RATA)) that must
28198 Federal Register / Vol. 63, No. 98 /Thursday, May 21, 1998 / Proposed Rules

be performed periodically for each

CEMS under Part 75. Relative accuracy

is expressed as a percent deviation of

the CEMS results from the reference

method results. The lower the relative

accuracy value for a CEMS, the closer its

measurements are to the reference

method. Under 40 CFR Part 75,

Appendix A, § 3, and Appendix B,

§ 2.3.1, all SO2, NOX, and CO2 CEMS are

required to have in a RATA a relative

accuracy of 10%. Those that have a

superior relative accuracy of 7.5% or

less have one year to undergo their next

RATA. Those that have a relative

accuracy equal to or less than the

required 10% but greater than 7.5%

must undergo their next RATA within

six months. The tighter specification of

7.5% is referred to as the ‘‘reduced

frequency standard,’’ while the 10%

specification is known as the ‘‘normal

frequency standard.’’ For flow monitors

the normal frequency standard is 15%,

while the reduced frequency standard is

10%. On January 1, 2000 the normal

and reduced frequency standards for

flow monitors will be lowered to

correspond to the standards for the

pollutant CEMS, i.e., 10% and 7.5%

respectively.

The evaluation of initial certification

test data submitted for 1993–1996

showed that the average relative

accuracy was 3.42% for the 965 SO2

CEMS installed under the Acid Rain

Program, 3.62% for 1272 NOX CEMS,

3.28% for 1097 CO2 CEMS., and 6.88%

for 1070 flow monitors. This means that

for all pollutants and flow, the average

relative accuracy was below the reduced

frequency standard. Furthermore, 91.3%

of all SO2 CEMS, 94.1% of all NOx

CEMS, 96.3% of all CO2 CEMS, and

91.9% of all flow monitors met their

respective reduced frequency standard.

See Docket Item, A–97–56, II–A–7 for a

complete analysis of the certification

test relative accuracy results.

A similar evaluation was performed

on the relative accuracy test results

reported in quarterly reports for the

1994–1996 period. This analysis

showed that the average relative

accuracy over the three years of data

was 3.49% on 2802 SO2 RATAs, 3.67%

on 3935 NOX RATAs, 3.06% on 2736

CO2 RATAs, and 5.78% on 3019 flow

RATAs. Like the certification test

results, the data in the quarterly reports

indicate that for each type of monitor,

the average relative accuracy was below

the reduced frequency standard. In

addition, on 96.2% of the SO2 RATAs,

96.0% of the NOX RATAs, 97.9% of the

CO2 RATAs, and 93.5% of flow RATAs,

the monitors met their respective

reduced frequency standard. A complete

analysis of the quarterly report relative

accuracy test results can be found in

Docket Item, A–97–56, II–A–8.

The relative accuracy test results

obtained by these installed CEMS imply

that no appreciable improvement in

achieved relative accuracies could be

expected unless the relative accuracy

standard were brought down to or below

these currently achieved average

relative accuracies. However, studies

cited above (Docket Item, A–97–56, II–

A–2 and II–A–5) of the variability of the

reference methods for SO2, NOX, and

CO2 suggest that such reduced relative

accuracy standards might be beyond the

technological limits of current

monitoring technology since they

approach the variability inherent in the

reference methods themselves. Thus,

tightening the relative accuracy

standards further for these CEMS is

unlikely to produce a corresponding

improvement in the achievable relative

accuracy.

Moreover, the existing regulations

already provide that the normal and

reduced frequency relative accuracy

standards for flow monitors will be

tightened to the same levels as for the

other CEMS beginning in the year 2000.

In light of the already low average

relative accuracy (reflecting high

monitor accuracy) for flow monitors,

there is little or no basis at this time for

concluding that any further tightening

would be appropriate. In addition, EPA

believes that the results of the tightening

in 2000 should be evaluated before any

further tightening is contemplated.

Therefore, based on the evaluation

required under § 75.8, the Agency

proposes to conclude that the current

performance specifications for relative

accuracy are appropriate at this time.

C. Availability Trigger Conditions for

Missing Data Substitution Procedure

In 40 CFR 75.30–75.38 (Subpart D) a

missing data procedure is prescribed for

calculating emissions when valid data

are not being supplied by a unit’s

continuous emissions monitoring

system. The missing data procedure is a

multi-tiered computational routine for

deriving a substitution value from

values previously recorded, or the

highest potential values, by the monitor.

The procedure is based on the premise

that the lower the annual monitor

availability and/or the longer the gap in

recorded data, the more conservative the

value to be substituted.

In concert, two trigger conditions

determine the conservativeness of the

substituted value. The first trigger

condition is annualized monitor

availability, i.e., the percentage of the

immediately preceding 8760 unit

operating hours in which valid, quality

assured data was obtained. The second

trigger condition is the length of the

current period during which valid data

are not being produced. Current

availability trigger conditions include

three tiers: (1) less than 90%

availability, (2) equal to or greater than

90% but less than 95% availability, and

(3) 95% or greater availability.

To determine if retaining the current

availability trigger conditions is

appropriate, the Agency analyzed the

annual percent monitor availability

(PMA) as reported in the 1994–1996

quarterly emission reports. The PMA

indicates the proportion of the operating

hours in each year that the monitor was

providing valid, quality assured

measurements. High PMAs would

indicate that current trigger conditions

are providing a sufficient incentive for

keeping monitors operating properly.

The evaluation of the quarterly report

data for 1994–1996 showed that the

average PMA for SO2 CEMS was 94.7%

in 1994, 96.7% in 1995, and 97.2% in

1996. For the same three year period it

was 91.8%, 94.1%, and 95.8% for NOx

CEMS, and 95.0%, 96.3%, and 97.0%

for flow monitors. As a rule, separate

percent monitor availabilities for the

CO2 CEMS are not routinely reported,

since CO2 CEMS usually serve as

diluent components in NOX systems.

However, the average PMA for CO2

CEMS in a given year must be at least

as good as the corresponding average of

the reported NOX PMAs. Not only are

the average PMAs above the 95%

availability trigger level, but they have

also consistently increased in each

successive year of the Acid Rain

Program. To appreciably improve

monitor availabilities would require

increasing the third tier availability

trigger up to or above the high average

availabilities currently being achieved.

EPA believes that such an increase in

the required availabilities would be

close to or beyond the limits of what is

reasonable to expect from current CEMS

technology when properly operated

under the conditions prevailing in

utility stacks. A complete summary of

the PMA’s submitted in the 1994–1996

quarterly reports can be found in Docket

Item, A–97–56, II–A–9.

Moreover, any tightening of the

availability trigger conditions would

require reprogramming of most affected

units’ data acquisition and handling

systems, which automatically calculate

and record the appropriate substitution

values for periods when valid CEMS

data are not available. Given the current

high levels of monitor availability, there

is little or no basis for finding that

adjusting the trigger conditions would

improve availability sufficiently to
Federal Register / Vol. 63, No. 98 /Thursday, May 21, 1998 / Proposed Rules 28199

justify the reprogramming costs that

such a change would impose.

Therefore, based on the evaluation

required under § 75.8, the Agency

proposes to determine that retaining the

current performance specifications for

availability trigger conditions is

appropriate at this time.

III. Proposed Rule Revisions

Having completed the studies and

evaluations required in 40 CFR 75.7 and

75.8 and in light of EPA’s

determinations proposed above for

retaining current rule provisions for the

bias test, relative accuracy, and

availability trigger conditions, EPA

proposes revising Part 75 to delete

§§ 75.7 and 75.8.

IV. Administrative Requirements

A. Executive Order 12866

Under Executive Order 12866, 58 FR

51735 (1993), the Administrator must

determine whether the regulatory action

is ‘‘significant’’ and therefore subject to

Office of Management and Budget

(OMB) review and the requirements of

the Executive Order. The Order defines

‘‘significant regulatory action’’ as one

that is likely to result in a rule that may:

(1) Have an annual effect on the

economy of $100 million or more or

adversely affect in a material way the

economy, a sector of the economy,

productivity, competition, jobs, the

environment, public health or safety, or

State, local, or tribal governments or

communities;

(2) Create a serious inconsistency or

otherwise interfere with an action taken

or planned by another agency;

(3) Materially alter the budgetary

impact of entitlements, grants, user fees,

or loan programs or the rights and

obligations of recipients thereof; or

(4) Raise novel legal or policy issues

arising out of legal mandates, the

President’s priorities, or the principles

set forth in the Executive Order.

Pursuant to the terms of Executive

Order 12866, it has been determined

that this proposed rule is a ‘‘significant

regulatory action’’ because the rule

seems to raise novel legal or policy

issues. As such, this action was

submitted to OMB for review. Any

written comments from OMB to EPA,

any written EPA response to those

comments, and any changes made in

response to OMB suggestions or

recommendations are included in the

docket. The docket is available for

public inspection at the EPA’s Air

Docket Section, which is listed in the

ADDRESSES section of this preamble.

B. Unfunded Mandates Act

Title II of the Unfunded Mandates

Reform Act of 1995 (UMRA), Pub. L.

104–4, establishes requirements for

federal agencies to assess the effects of

their regulatory actions on State, local,

and tribal governments and the private

sector. Under section 202 of the UMRA,

EPA generally must prepare a written

statement, including a cost-benefit

analysis, before promulgating a

proposed or final rule that includes a

federal mandate that may result in

expenditure by State, local, and tribal

governments, in aggregate, or by the

private sector, of $100 million or more

in any one year. Section 205 generally

requires that, before promulgating a rule

for which a written statement must be

prepared, EPA identify and consider a

reasonable number of regulatory

alternatives and adopt the least costly,

most cost-effective, or least burdensome

alternative that achieves the objectives

of the rule. The provisions of section

205 do not apply when they are

inconsistent with applicable law.

Moreover, section 205 allows EPA to

adopt an alternative other than the least

costly, most cost-effective, or least

burdensome alternative if the

Administrator explains why that

alternative was not adopted. Finally,

section 203 requires that, before

establishing any regulatory

requirements that may significantly or

uniquely affect small governments, EPA

must have developed a small

government agency plan. The plan must

provide for notifying any potentially

affected small governments, enabling

officials of affected small governments

to have meaningful and timely input in

the development of EPA regulatory

proposals with significant federal

intergovernmental mandates, and

informing, educating, and advising

small governments on compliance with

the regulatory requirements.

Because this proposed rule is

estimated to result in the expenditure by

State, local, and tribal governments or

the private sector of less than $100

million in any one year, the Agency has

not prepared a budgetary impact

statement or specifically addressed the

selection of the least costly, most costeffective, or least burdensome

alternative. Because small governments

will not be significantly or uniquely

affected by this rule, the Agency is not

required to develop a plan with regard

to small governments.

As discussed above, the proposed rule

would eliminate two sections requiring

studies and evaluations by EPA of

certain existing regulatory provisions

and would not include any other

changes to the existing regulations. The

proposed rule therefore would not

change in any way the expenditure by

State, local, and tribal governments or

the private sector, or the effect on small

governments, resulting from the existing

regulations.

C. Paperwork Reduction Act

This action proposing revisions to the

continuous emission monitoring

regulations would not impose any new

information collection burden. OMB has

previously approved the information

collection requirements contained in the

continuous emission monitoring

regulations, 40 CFR part 75, under the

provisions of the Paperwork Reduction

Act, 44 U.S.C. 3501, et seq. Note,

however, that the Agency is proposing

other revisions to the continuous

emission monitoring regulations in a

separate action in today’s Federal

Register and that those revisions would

result in a change to the current

information collection burden.

Burden means the total time, effort, or

financial resources expended by persons

to generate, maintain, retain, or disclose

or provide information to or for a

Federal agency. This includes the time

needed to review instructions; develop,

acquire, install, and utilize technology

and systems for the purposes of

collecting, validating, and verifying

information, processing and

maintaining information, and disclosing

and providing information; adjust the

existing ways to comply with any

previously applicable instructions and

requirements; train personnel to be able

to respond to a collection of

information; search data sources;

complete and review the collection of

information; and transmit or otherwise

disclose the information.

D. Regulatory Flexibility

The Regulatory Flexibility Act, 5

U.S.C. 601, et seq., generally requires

federal agencies to conduct a regulatory

flexibility analysis of any rule subject to

notice and comment rulemaking

requirements unless the agency certifies

that the proposed rule will not have a

significant economic impact on a

substantial number of small entities.

Small entities include small businesses,

small not-for-profit enterprises, and

small governmental jurisdictions.

As discussed above, the proposed rule

would eliminate two sections requiring

studies and evaluations by EPA and

would not include any other changes to

the existing regulations. The proposed

rule therefore does not change in any

way the potential impacts on small

entities resulting from the existing

regulations. Therefore, I hereby certify
28200 Federal Register / Vol. 63, No. 98 /Thursday, May 21, 1998 / Proposed Rules

that this action will not have a

significant economic impact on a

substantial number of small entities.

List of Subjects in 40 CFR Part 75

Environmental protection, Air

pollution control, Carbon dioxide,

Continuous emissions monitors, Electric

utilities, Nitrogen oxides, Reporting and

recordkeeping requirements, Sulfur

dioxide.

Dated: April 27, 1998.

Carol M. Browner,

Administrator.

For the reasons set out in the

preamble, part 75 of title 40, chapter 1

of the Code of Federal Regulations is

proposed to be amended as follows:

PART 75—[AMENDED]

1. The authority citation for part 75

continues to read as follows:

Authority: 42 U.S.C. 7601 and 7651, et seq.

2. Section 75.7 is removed and

reserved.

3. Section 75.8 is removed and

reserved.

[FR Doc. 98–11750 Filed 5–20–98; 8:45 am]

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