11724 Federal Register / Vol. 62, No. 48 / Wednesday, March 12, 1997 / Rules and Regulations

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 132

[FRL–5708–8]

RIN 2040–AC94

Final Revisions to the Polychlorinated

Biphenyl Criteria for Human Health and

Wildlife for the Water Quality Guidance

for the Great Lakes System

AGENCY: Environmental Protection

Agency (EPA).

ACTION: Final rule.

SUMMARY: EPA is publishing final

revisions to the polychlorinated

biphenyl (PCB) ambient water quality

criteria for human health and wildlife

for the final Water Quality Guidance for

the Great Lakes System that was

published in March 1995 (the 1995

Guidance). The final revisions are

limited to the method for calculating a

composite baseline bioaccumulation

factor (BAF) for PCBs and the method

for calculating a composite octanolwater partition coefficient (Kow) for

PCBs. After reviewing all public

comments, EPA concluded that the

approach it proposed in October 1996

for calculating a composite baseline

BAF, using the second alternative

proposed for calculating a composite

Kow, for PCBs would be preferable to the

approach used in the 1995 Guidance

because it would more appropriately

relate the concentrations of the PCB

congeners in tissue to the

concentrations of the PCB congeners in

water. Consequently, EPA is today

revising the human health cancer

criterion for PCBs from 3.9E–6 ug/L to

6.7E–6 ug/L, and the wildlife criterion

for PCBs from 7.4E–5 ug/L to 1.2E–4 ug/

L. EPA believes that these revisions

more accurately represent the numerical

limits necessary to protect human

health and wildlife in the Great Lakes

System.

EFFECTIVE DATE: March 12, 1997.

ADDRESSES: The public docket for this

rulemaking, including the proposal,

public comments in response to the

proposal, other major supporting

documents, and the index to the docket

are available for inspection and copying

at U.S. EPA Region 5, 77 West Jackson

Blvd., Chicago, IL 60604 by

appointment only. Appointments may

be made by calling Mary Willis Jackson

(telephone 312–886–3717).

FOR FURTHER INFORMATION CONTACT:

Mark Morris (4301), U.S. EPA, 401 M

Street, SW, Washington, D.C. 20460

(202–260–0312).

SUPPLEMENTARY INFORMATION:

I. Introduction

A. Potentially Affected Entities

Entities potentially affected by this

final rule are those discharging

pollutants to waters of the United States

in the Great Lakes System. Potentially

affected categories and entities include:

Category Examples of potentially affected entities

Industry ............. Industries discharging

PCBs to waters in the

Great Lakes System as

defined in 40 CFR 132.2.

Municipalities .... Publicly-owned treatment

works discharging PCBs

to waters of the Great

Lakes System as defined

in 40 CFR 132.2.

This table is not intended to be

exhaustive, but rather provides a guide

for readers regarding entities likely to be

affected by this final rule. This table

lists the types of entities that EPA is

now aware could potentially be affected

by this action. To determine whether

your facility may be affected by this

final rule, you should examine the

definition of ‘‘Great Lakes System’’ in 40

CFR 132.2 and examine 40 CFR 132.2

which describes the purpose of water

quality standards such as those

established in this rule. If you have any

questions regarding the applicability of

this action to a particular entity, consult

the person listed in the preceding FOR

FURTHER INFORMATION CONTACT section.

B. Great Lakes Water Quality Guidance

In March 1995, EPA promulgated the

final Water Quality Guidance for the

Great Lakes System (the 1995 Guidance)

required under section 118(c)(2) of the

Clean Water Act, 33 U.S.C. 1268(c)(2).

See 60 FR 15366–425 (March 23, 1995).

The ambient water quality criteria

(AWQC) included in the 1995 Guidance

to protect human health and wildlife set

maximum ambient concentrations for

harmful pollutants to be met in all

waters in the Great Lakes System unless

site-specific criteria are derived and

approved. See 40 CFR Part 132, Tables

3 and 4. Great Lakes States and Tribes

must adopt criteria consistent with

EPA’s criteria by March of 1997. CWA

section 118(c)(2). If any State or Tribe

fails to meet that deadline, EPA must

promulgate criteria that will apply in

that State’s or Tribe’s jurisdiction. Id.

Once the criteria take effect, permits for

discharges of such pollutants into the

Great Lakes System must include limits

as necessary to attain the criteria.

EPA promulgated human health and

wildlife criteria for a class of closely

related toxic pollutants known as

polychlorinated biphenyls (PCBs). The

PCB criteria for human health and

wildlife incorporate bioaccumulation

factors (BAFs) which reflect the fact that

PCBs magnify at several steps in aquatic

food chains, so that humans and

wildlife that eat fish from the Great

Lakes may be exposed to PCB

concentrations many times higher than

the PCB concentration in the waters of

the Lakes. Different members of the

class of PCBs (called ‘‘congeners’’) have

different potentials to bioaccumulate. In

the 1995 Guidance, EPA derived a

single baseline BAF for PCBs for each

trophic level by computing a weighted

geometric mean baseline BAF from the

baseline BAFs for each trophic level for

approximately 50 PCB congeners.

Based on issues raised as part of a

lawsuit on the 1995 Guidance, in 1996

EPA proposed a different approach for

calculating a single BAF for the class of

PCBs. EPA also decided to call this

single BAF a ‘‘composite baseline BAF.’’

The new approach also required EPA to

calculate a composite Kow for PCBs. EPA

proposed two different approaches for

this calculation. EPA, however,

presented calculations of revised BAFs

and revised ambient water quality

criteria based on only one of the two

Kow alternatives. For a more complete

discussion of the 1995 Guidance and the

revised approach in the 1996 proposal,

refer to 60 FR 15366 (March 23, 1995)

and 61 FR 54748 (October 22, 1996).

After considering all comments, EPA

has decided to follow the proposed

approach. EPA selected the second of

the two alternatives to calculating a

composite Kow. As a result, the

numerical values for the final BAFs and

the final criteria differ very slightly from

those that EPA presented in the

proposal. The discussion below

explains the reasons for the changes.

II. Background

The BAFs in the 1995 Guidance relate

the concentration of a chemical

measured in water to the concentration

of the same chemical measured in fish

tissue. Under the methodology for the

1995 Guidance, the calculation of a BAF

that is to be used for calculating AWQC

for a non-polar organic chemical

involves three steps for each trophic

level. First, EPA obtains a ‘‘total’’ BAF

based on the total concentrations of the

chemical in the water and in the aquatic

biota, based on field measurements.

Second, EPA converts this initial total

BAF into a ‘‘baseline’’ BAF that reflects

the amount of lipid (fat) in the aquatic

biota that was assessed and the amount
Federal Register / Vol. 62, No. 48 / Wednesday, March 12, 1997 / Rules and Regulations 11725

of freely dissolved chemical that was

estimated in the water. This permits

better extrapolation of data from one

species to another and from one water

body to another. Third, EPA computes

a final ‘‘total’’ BAF based on the total

concentration of the chemical in the

water and the organisms at the site to be

protected. In this notice, EPA will refer

to the first ‘‘total’’ BAF as the ‘‘initial

total’’ BAF, and the final as the ‘‘final

total’’ BAF. The initial and final total

BAFs generally differ because they

usually apply to different bodies of

water.

An important factor in the calculation

of the baseline BAF and both total BAFs

for a chemical is the Kow for that

chemical. The Kow is a measure of the

affinity of a chemical to partition

between octanol and water and is used

as an estimate of the partitioning

between the lipids (fatty tissues) of an

aquatic organism and water. The higher

the Kow, all other factors being constant,

the greater the affinity of the chemical

to concentrate in fish tissue. Each

chemical has a Kow value. The Kow value

for a chemical is usually reported as the

log Kow for the chemical. When

calculating total and baseline BAFs for

a chemical, the chemical-specific Kow is

used to estimate the freely dissolved

fraction of the chemical in the water.

When this methodology is used to

derive human health and wildlife

AWQC for a class of chemicals, the

normal ‘‘single’’ values for baseline and

total BAFs for an individual chemical

are replaced by composite baseline and

composite total BAFs for the class to

simplify the equations. Using a

composite value in a calculation for the

class gives the same result as summing

the results of calculations for each

member of the class. When calculating

a composite baseline BAF or a

composite total BAF for all of the

chemicals in a class at a trophic level,

it is necessary to use a composite Kow.

This composite Kow is used to estimate

the composite freely dissolved fraction

of the class of chemicals in the Great

Lakes waters.

EPA based the PCB BAFs in the 1995

Guidance on a field study conducted in

the Great Lakes by Oliver and Niimi

(1988). The study collected data on

numerous PCB congeners, and EPA

calculated a separate baseline BAF for

each congener using separate, congenerspecific Kows. EPA, however, needed to

calculate composite baseline BAFs and

composite total BAFs representing all

congeners at a trophic level in order to

calculate AWQC for human health and

wildlife, because there is a single

‘‘cancer potency factor’’ which is used

for evaluating human health cancer risk

for all PCBs. Similarly, for wildlife,

there is a single toxicity factor which is

used in the derivation of the wildlife

criterion. Consequently, composite

baseline and total BAFs were needed in

order to be consistent with the toxicity

data available to derive human health

and wildlife criteria.

In the 1995 Guidance, EPA calculated

a composite baseline BAF for PCBs for

trophic level 3 and a composite baseline

BAF for trophic level 4 by computing a

weighted geometric mean of the

baseline BAFs for individual PCB

congeners at each trophic level. The

weighted geometric mean baseline BAF

was 55,281,000 for trophic level 3 and

116,553,000 for trophic level 4. As

explained above, when calculating a

composite baseline BAF for PCBs, EPA

must also use a composite Kow. In the

1995 Guidance, EPA calculated a

weighted geometric mean Kow of

3,885,000 (mean log Kow of 6.589) by

weighting the log Kows for the

individual PCB congeners by the

concentrations of the PCB congeners in

fish. The weighted mean log Kow of

6.589 was then used to estimate the

freely dissolved fraction of the PCB

congeners in the study of Oliver and

Niimi (1988). The log Kows for the

individual PCB congeners used in the

final Guidance came from Hawker and

Connell (1988).

Using the composite baseline BAF for

each trophic level and the weighted

mean log Kow of 6.589, EPA calculated

composite final total BAFs of 520,900

for trophic level 3 and 1,871,000 for

trophic level 4 for use in calculating

human health criteria. The PCB human

health cancer criterion calculated using

these BAFs was 3.9E–6 ug/L. For

wildlife, the composite final total BAFs

were 1,850,000 for trophic level 3 and

6,224,000 for trophic level 4. The PCB

wildlife criterion derived using these

BAFs was 7.4E–5 ug/L.

Various industries and trade

associations challenged the human

health and wildlife criteria for PCBs.

AISI v. EPA, D.C. Cir. No.95–1348 and

consolidated cases. Among the issues

they raised was the calculation of the

composite baseline BAF as the weighted

geometric mean for PCBs. The AISI

petitioners alleged that the equation was

mathematically inappropriate for a

variety of reasons. As a result of this

challenge, EPA re-examined the basis

for the calculation of the composite

baseline BAF as the weighted geometric

mean. For a more complete discussion

of bioaccumulation and the approach

used in the 1995 Guidance, refer to 58

FR 20803 (April 16, 1993), and the

Procedure to Determine

Bioaccumulation Factors (‘‘TSD for

BAFs’’)(EPA–820–B–95–005).

III. Revised Method for Calculating

Composite Baseline BAFs for PCBs

A. The Proposed Approach

On October 22, 1996, EPA proposed a

revised approach for calculating the

composite baseline BAF for PCBs for

each trophic level. The revised

approach uses the sum of all

concentrations of PCB congeners in

tissue and the sum of all concentrations

of PCB congeners in the ambient water,

as reported in Oliver and Niimi (1988),

to calculate a composite initial total

BAF for PCBs at each trophic level. This

approach is equivalent to using a

weighted arithmetic mean of all the

measured initial total BAFs from the

PCB congeners, where the weights are

the concentrations of the PCB congeners

in water. EPA believes this approach is

consistent with the definition of

bioaccumulation factor and

appropriately relates the sum of the

concentrations of the PCB congeners in

tissue to the sum of the concentrations

of the PCB congeners in water. EPA

further believes that this approach will

provide an accurate composite initial

total BAF for the class of PCBs.

As part of the October 22, 1996

proposal, EPA also proposed to revise

its approach for calculating the

composite Kow used in the calculation of

the composite baseline and total BAFs.

EPA proposed two alternatives: the first

alternative used the median log Kow of

the PCB congeners to derive a composite

Kow; the second used the sum of the

concentrations of the Kows for all

congeners together with the sum of all

of the freely dissolved concentrations of

the congeners in water. For a more

complete discussion of the revised

approach for calculating composite

BAFs and Kows, refer to 61 FR 54748

(October 22, 1996).

B. Comments on the Proposed Approach

EPA received three comments on the

proposal. Two commenters opposed the

revised approach for calculating

composite BAFs for PCBs. One of the

commenters who opposed the proposal

argued that the revised approach

yielded less stringent criteria for PCBs

and that this action was contradictory to

the principle of zero discharge, and

inconsistent with what the public had

been told about the 1995 Guidance

methodology being a superior method

yielding more stringent criteria. This

commenter also argued that the

resulting higher criteria would allow

backsliding for pollution prevention

scenarios currently established and
11726 Federal Register / Vol. 62, No. 48 / Wednesday, March 12, 1997 / Rules and Regulations

operating for existing permitted

discharges of PCBs. The other

commenter who opposed the proposal

was concerned that data (congener

specific Kows, tissue and water PCB

concentrations) used in the revised

approach were taken from reports that

were published a decade ago and that

more recent data on the behavior of

PCBs in the environment, their activity

as carcinogenic promoters, and the

tendency of ‘‘weathered’’ PCBs to be

more toxic than the parent compounds,

have not been considered. This

commenter argued that the revised

approach did not provide as much

protection against the tendency for PCBs

to become more toxic over time. In

addition, the commenter argued that, if

EPA were to revise the 1995 approach,

it should not use the median value

because the median ignores extremely

high or low values, disregards

population trends, and does not weigh

skewness, which is a characteristic of

the PCBs. In fact, the commenter

recommended that EPA compute and

use a BAF at the 90 percent confidence

level. Finally, the commenter also noted

that, since a higher Kow also affects the

amount of pollutant that is freely

dissolved, the change in the Kow value

has a large impact on the final criterion.

For these reasons the commenter argued

that the 1995 approach, which produces

the lowest composite Kow was

preferable. However, the commenter

concluded that, if EPA revised its

approach, it should use the second of

the two alternatives proposed, because

it produces a lower Kow than the first

alternative.

Finally, one commenter supported the

revised approach stating that the

proposed modifications to the equation

used to calculate the composite BAFs

for PCBs are scientifically and

mathematically appropriate. However,

the commenter further stated that it

disagrees with many other issues arising

from the 1995 Guidance and EPA’s

derivation of BAFs for PCBs, which are

issues outside the scope of this

rulemaking.

C. Response to Comments

EPA appreciates those who provided

comments on this rulemaking. In regard

to the first comment, EPA disagrees that

it has misinformed the public

concerning either the 1995 Guidance

methodology or the 1996 revised

methodology. EPA also disagrees with

the prediction that the revised criteria

will result in backsliding. Although the

revised criteria are less stringent than

the 1995 criteria, they are not less

stringent than the PCB criteria currently

in effect in the Great Lakes States.

Currently, the range of water quality

criteria being implemented in the Great

Lakes Basin to protect human health

from PCBs is 0.1 to 0.00008 ug/L. EPA’s

revised methodology produces a human

health criterion for PCBs that is about 10

to 10,000 times more stringent than

those currently being implemented. For

the protection of wildlife the disparity

is even more dramatic because many of

the Great Lakes States do not have

criteria for PCBs to protect wildlife. For

the three Great Lakes States that do have

criteria for PCBs to protect wildlife,

EPA’s revised approach produces a

wildlife criterion that is approximately

10 to 1,000 times more stringent than

those currently being implemented.

Given this information, EPA does not

believe that permit limits for PCBs

based on criteria for human health and

wildlife produced by the revised

methodology will result in less

protection or backsliding. Further, EPA

interprets the concept of zero discharge

in the Great Lakes Agreement as a goal

toward which it is working. The revised

PCB criteria, which are still more

stringent than criteria currently in effect

in the Great Lakes States, are a

reasonable and substantial step toward

that goal.

EPA also disagrees with the comment

that asserts that EPA should chose an

approach to calculating a composite Kow

that leads to a more conservative PCB

criterion because the current criteria

may not sufficiently take into account

the effects of ‘‘weathering’’ or data from

new studies suggesting that PCBs might

cause reproductive and developmental

toxicity effects. EPA believes that the

BAF should estimate bioaccumulation

as accurately as possible. EPA believes

it is more appropriate to account for the

commenter’s concerns—if warranted—

by adjusting its estimate of PCB’s

toxicity. Further, EPA believes that it

has adequately accounted for

weathering. PCBs were first introduced

into the Great Lakes Basin in the 1930s.

Researchers in the Great Lakes have

spent a significant amount of time

gathering data and studying the fate and

effects of PCBs in this system. Given the

length of time some of the PCBs have

resided in the Great Lakes Basin, any

increased toxicity due to ‘‘weathering’’

would be reflected in the data collected

in 1986. Therefore, EPA does not agree

that it needs to retain the 1995 approach

to ensure protection against the possible

impacts of weathering.

EPA agrees that some recent data

indicate that PCBs, particularly coplanar PCBs, might cause reproductive

and developmental toxicity through

processes such as endocrine disruption.

Because concentrations associated with

such potential adverse effects are under

evaluation, EPA can not yet predict

whether such effects might occur at

concentrations above or below those

associated with the cancer risks

modeled by the 1995 Guidance. EPA

does not believe that it has enough

information concerning these

additional, potential effects to revise the

criteria at this time. As stated in the

1995 Guidance, EPA is committed to

improving the science supporting its

methodologies and criteria, and will

continue to evaluate and revise them in

future rulemakings in light of new

information, as appropriate.

EPA agrees with the comment that the

median Kow of the PCB congeners

should not be used as the composite Kow

and that the second alternative set forth

in the proposal is more appropriate.

EPA also agrees with some of the

limitations identified by the commenter

that are associated with using a median.

However, EPA’s reason for adopting the

second alternative to calculate a

composite Kow as part of this final rule

is not because it introduces, as the

commenter suggests, a more protective

value, but because EPA believes that the

second alternative more accurately

reflects how PCBs behave in the Great

Lakes System. The second alternative

provides the same result as would be

obtained by performing the relevant

calculations for each congener and then

summing the results.

D. Final Action

As described above, the approach for

this final rule uses the sum of the

concentrations of all PCB congeners in

tissue and the sum of the concentrations

of all PCB congeners in the ambient

water to calculate a composite initial

total BAF for PCBs at each trophic level.

The approach also uses individual PCB

congener Kow to calculate the composite

Kow. The calculations of the composite

baseline BAFs for PCBs, the composite

final total BAFs to be used in the

calculation of AWQC for wildlife and

human health, and the PCB criteria for

wildlife and humans using the new PCB

BAFs are presented below. EPA is not

revising the data used in the calculation

of the composite BAFs or composite

Kows or other aspects related to the

derivation of the human health and

wildlife criteria for PCBs. The fish tissue

data, water column data, and log Kow

values used to calculate the new

composite BAFs and composite Kow are

identical to those used in the 1996

proposal.
Federal Register / Vol. 62, No. 48 / Wednesday, March 12, 1997 / Rules and Regulations 11727

1. Calculation of Composite Baseline

BAFs for PCBs

The equation used to calculate a

baseline BAF for an individual chemical

for each individual trophic level in this

final rule is the same as was used in the

1995 Guidance and the 1996 proposal

(61 FR 54748). The equation to calculate

a baseline BAF when a field-measured

BAF is available for a chemical, as is the

case with PCBs, is (each of the three

components for calculating a baseline

BAF is discussed below):

Baseline BAF

Measured BAF

f f

T

t

fd

= −



























1 

1

l

Where:

Measured BAFt

T = BAF based on total

concentration in tissue and water

(i.e., a total BAF).

fl = fraction of the tissue that is lipid.

ffd = fraction of the total chemical in the

ambient water that is freely

dissolved.

By comparison, the equation for

calculating a composite baseline BAF is:

Composite Baseline BAF Composite Initial Total BAF

Composite f f fd

= −



























1 

1

l

a. Composite Initial Total BAF

To calculate a composite initial total

BAF for trophic level 4, the data needed

are the total concentration of the

chemical in the tissue of a trophic level

4 species and the total concentration of

the chemical in ambient water at the site

of sampling. The trophic level 4 species

used in the 1995 Guidance, the 1996

proposal and this final rule are

salmonids. To calculate a composite

initial total BAF for trophic level 3, the

data needed are the total concentration

of the chemical in the tissue of a trophic

level 3 species and the total

concentration of the chemical in

ambient water at the site of sampling.

The trophic level 3 species used in the

1995 Guidance, the 1996 proposal and

this final rule are sculpins and alewives.

The average of the values for the

sculpins and alewives is used to

represent the trophic level 3 values. The

equation to calculate a composite total

BAF is:

Composite Total BAF Total concentration of chemical in tissue

Total concentration of chemical in ambient water =

For trophic level 4, the total

concentration of PCB congeners in fish

tissue (salmonids) is 4057.3 ng/g and

the total concentration of PCB congeners

in ambient water is 1006.1 pg/L. For

trophic level 3, the average of the total

concentrations of PCB congeners in

tissue from sculpins and alewife is

1393.15 ng/g. These values were derived

in the 1996 proposal from Oliver and

Niimi (1988).

Composite Initial Total BAF Trophic Level ng g pg ng g L

pg L

Composite Initial Total BAF Trophic Level ng g pg ng g L

pg L

− = ( )( )( ) =

− = ( )( )( ) =

4

4057 3 1000 1000

1006 1

4 033 000

3

139315 1000 1000

1006 1

1 385 000

. / / /

. / , ,

. / / /

. / , ,

The resulting composite initial total

BAF is 4,033,000 for trophic level 4 and

1,385,000 for trophic level 3 (rounded to

four significant figures as discussed on

page G–2 of the TSD for BAFs).

b. Composite Fraction Freely Dissolved

To estimate the fraction of PCBs that

are freely dissolved in the ambient

water requires information on the

particulate organic carbon (POC) and

dissolved organic carbon (DOC) in the

ambient water where the samples were

collected and the Kow of the chemical.

As in the 1995 Guidance and the 1996

proposal, the equation for calculating

the fraction freely dissolved for an

individual chemical is:

f

POC K DOC K fd

ow ow

=

[ ] + × ( ) + × ( )

1

1 10 /

Where:

POC=concentration of particulate organic carbon (kg/L).

DOC=concentration of dissolved organic carbon (kg/L).

Kow=n-octanol water partition coefficient for the chemical.
11728 Federal Register / Vol. 62, No. 48 / Wednesday, March 12, 1997 / Rules and Regulations

By comparison, to calculate a composite fraction freely dissolved for a group of chemicals, the equation is:

Composite f POC Composite K DOC Composite K fd

ow ow

=

[ ] + × ( ) + × ( )

1

1 10 /

The log Kows used for the individual PCB congeners come from Hawker and Connell (1988), which were included

in the 1996 proposal. To calculate the composite Kow, as explained above, EPA will not employ the first alternative

that uses the median log Kow from the log Kows presented in Table 1 of the 1996 proposal (61 FR 54752), but will

instead use the second alternative for calculating a composite Kow. As proposed, the formula for calculating the second

alternative composite Kow is:

Where:

Composite K DOC POC

C

C

ow

w

t

i

n

w

fd

i

n =

+





















−

























=

=

∑

∑

1

10

1 1

1

Where:

i=1, 2, * * * n congeners.

Ct

w=total concentration of the congener in water.

Cfdw=freely dissolved concentration of the congener in water.

The second alternative for calculating the composite Kow was derived algebraically from the following definition of

the fraction freely dissolved, ffd, for a single congener, as given in the 1995 Guidance and the 1996 proposal :

f C

C

POC K

DOC K fd w

fd

w

t

ow

ow

= =

+ ( )( ) + ( )( )

1

1

10

In the second alternative for the composite Kow, the ratio of the sum of the total concentrations of all of the

congeners in water over the sum of the freely dissolved concentrations of all of the congeners in water is substituted

for the ratio of the total over freely dissolved concentration of a single congener in water. Using the data provided

in Table 1 of the 1996 proposal, these equations yield a composite Kow of 2,189,000 (rounded to four significant figures).

Composite Kow = ×

+





















− 





 = −

1

2 0 10

10

0

1006 1

699 72

1 2 189 000 6 .

.

. , ,

This differs slightly from the composite Kow value of 2,238,721 derived in the proposal using the median log Kow

approach.

In the 1995 Guidance and the 1996 proposal, the POC value used was 0.0 kg/L and the DOC value used was

2.0×10¥6 kg/L for the study of Oliver and Niimi (1988). In this final rule, EPA is not changing these values. Using

these values and the revised composite Kow value of 2,189,000 the composite fraction freely dissolved in this final

rule is 0.6955, as shown below:

Composite ffd =

[ ] + × ( ) + × × ( ) = −

1

1 0 2 189 000 2 0 10 2 189 000 10

0 6955

6 , , . , , /

.

Again, this differs slightly from the fraction freely dissolved presented in the 1996 proposal. The difference stems

from the use of the second alternative for calculating a composite Kow.

c. Fraction Lipid

In addition, EPA is not changing the fraction lipid content of the salmonids (0.11) or sculpin (0.08) or alewife

(0.07) that were used in the 1995 Guidance and the 1996 proposal for the study of Oliver and Niimi (1988). The

average fraction lipid for sculpin and alewife is 0.075.

d. Composite Baseline BAF

Based on the information presented above and using the equation for calculating composite baseline BAFs, EPA

calculates for this final rule a new composite baseline BAF for PCBs for trophic level 4 of 52,720,000 and a new

composite baseline BAF for PCBs for trophic level 3 of 26,550,000 (rounded to four significant figures). Composite

Baseline BAF TL4

Composite Baseline BAF TL3

1 000

0 6955

1

1

0 075 = − 26 550 000 



 









 



 = ,385,

. . , ,
Federal Register / Vol. 62, No. 48 / Wednesday, March 12, 1997 / Rules and Regulations 11729

2. Calculation of Composite Final Total BAFs for Use in AWQC

The data required to calculate a composite final total BAF for use in deriving a AWQC for PCBs are the composite

baseline BAF, the fraction lipid of the aquatic species consumed by the population of interest whether that is humans

or wildlife and the composite fraction freely dissolved in the ambient water for the area of interest.

Composite Total BAF for AWQC = [(Composite Baseline BAF)(Fraction Lipid of Aquatic Species Consumed) + 1](Composite

ffd)

a. Composite Baseline BAF

The new composite baseline BAFs

derived above in section III.D will be

used: 52,720,000 for trophic level 4 and

26,550,000 for trophic level 3.

b. Composite Freely Dissolved Fraction

The equation for calculating the

composite freely dissolved fraction is

presented above. EPA is using the same

values for POC and DOC used in the

1995 Guidance and the 1996 proposal

(4.0 x 10–8 kg/L for POC and 2.0 x 10¥6

kg/L for DOC). These values represent

POC and DOC concentrations in Lake

Superior and were used to calculate all

of the final total BAFs that were used to

derive the AWQC in the 1995 Guidance.

Both the composite Kow and the

composite freely dissolved fraction must

be calculated using the Lake Superior

values for POC and DOC. The relative

total concentrations of the PCB

congeners in Lake Superior will be

assumed to be the same as in Oliver and

Niimi (1988). The resulting composite

Kow is 2,107,000 and the composite ffd

is 0.6642 (both rounded to four

significant figures).

Composite KOW = ×

+ ×

























− 



 



 = − −

1

2 0 10

10

4.0 10

1006 1

668 2

1 2 107 000 6 . 8

.

. , ,

Composite ffd =

[ ] + × × ( ) + × × ( ) = − −

1

1 4.0 10 2 107 000 2 0 10 2 107 000 10

0 6642

8 6 , , . , , /

.

The freely dissolved fraction of 0.6642

differs slightly from the value of 0.6505

presented in the 1996 proposal. The

difference is due to the change in the

method for calculating the composite

Kow.

c. Lipid Fraction

EPA is not changing the lipid values

used in the 1995 Guidance and the 1996

proposal. The lipid fraction of the

aquatic species consumed by humans in

the Great Lakes region is 1.82 for trophic

level 3 and 3.10 for trophic level 4. For

wildlife, the lipid fraction for trophic

level 3 is 6.46 and for trophic level 4 is

10.31.

d. Composite Final Total BAFs for

Calculating AWQC

Using the above values for the

composite baseline BAFs, composite

freely dissolved fraction for Lake

Superior and fraction lipid, EPA today

is promulgating the following composite

final total BAFs (rounded to four

significant figures) to be used in

deriving the human health and wildlife

AWQC for PCBs:

Human Health BAF for Trophic Level 4

= [(52,720,000)(0.0310) +1] 0.6642 =

1,086,000

Human Health BAF for Trophic Level 3

= [(26,550,000)(0.0182) +1] 0.6642 =

321,000

Wildlife BAF for Trophic Level 4 =

[(52,720,000)(0.1031) +1] 0.6642 =

3,610,000

Wildlife BAF for Trophic Level 3 =

[(26,550,000)(0.0646) +1] 0.6642 =

1,139,000

3. Human Health Cancer Criteria

Based on the BAFs presented above,

EPA today is revising the human health

cancer criteria for PCBs in Table 3 of the

1995 Guidance from 3.9E–6 μg/L to

6.7E–6 μg/L. The equations used to

calculate the human health cancer

criteria for PCBs in this final rule are the

same as were used in the 1995 Guidance

and the 1996 proposal (61 FR 54753).

4. Wildlife Criterion

For wildlife, EPA today is revising the

PCB criterion from 7.4E–5 μg/L to 1.2E–

4 μg/L based on using the BAFs

presented above. The equations used to

calculate the wildlife criterion for PCBs

in this final rule are the same as were

used in the 1995 Guidance and the 1996

proposal (61 FR 54754).

IV. Effective Date

Section 553(d)(3) of the

Administrative Procedure Act requires

Federal agencies to publish final rules at

least 30 days before they take effect

unless they find that they have ‘‘good

cause’’ to waive the notice requirement.

EPA finds that it has good cause to

waive the 30-day notice requirement for

these revisions to the PCB criteria. EPA

needs to make this rule effective as soon

as possible to maximize the ability of

the States and Tribes to use the new

criteria in their Guidance submissions

that are due in March 23, 1997. Also, in

this case an immediate effective date

does not conflict with the goal of the

notice requirement (giving the public

the opportunity to adjust behavior

before the rule imposes penalties). The

revised criteria will not affect any

member of the public until they are

adopted by a Great Lakes State or Tribe

(or promulgated by EPA where a State

or Tribe fails to submit adequate

criteria). EPA anticipates that these

processes will take at least 30 days, so

that the public will receive adequate

notice of the revised requirements

before they become binding.

V. Executive Order 12866

Under Executive Order 12866 (58 FR

51735, October 4, 1993), EPA must

determine whether the regulatory action

is ‘‘significant’’ and therefore subject to
11730 Federal Register / Vol. 62, No. 48 / Wednesday, March 12, 1997 / Rules and Regulations

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 final rule is not a ‘‘significant

regulatory action’’ and is therefore not

subject to OMB review.

VI. Submission to Congress and the

General Accounting Office

Under 5 U.S.C. 801(a)(1)(A) as added

by the Small Business Regulatory

Enforcement Fairness Act of 1996, EPA

submitted a report containing this rule

and other required information to the

U.S. Senate, the U.S. House of

Representatives and the Comptroller

General of the General Accounting

Office prior to publication of the rule in

today’s Federal Register. This rule is

not a ‘‘major rule’’ as defined by 5

U.S.C. 804(2).

VII. Regulatory Flexibility Act as

Amended by the Small Business

Regulatory Enforcement Fairness Act of

1996

The Regulatory Flexibility Act (RFA)

provides that, whenever an agency

promulgates a final rule under 5 U.S.C.

553, after being required to publish a

general notice of proposed rulemaking,

an agency must prepare a final

regulatory flexibility analysis unless the

head of the agency certifies that the

proposed rule will not have a significant

economic impact on a substantial

number of small entities. 5 U.S.C. 604

& 605.

Under the CWA, EPA’s promulgation

of water quality standards establishes

standards that the States implement

through the National Pollutant

Discharge Elimination System (NPDES)

permit process. The States have

discretion in deciding how to meet the

water quality standards and in

developing discharge limits as needed

to meet the standards. While State

implementation of federallypromulgated water quality standards

may result in new or revised discharge

limits being placed on small entities, the

standards themselves do not apply to

any discharger, including small entities.

Today’s rule imposes obligations on

the Great Lakes States but, as explained

above, does not itself establish any

requirements that are applicable to

small entities. As a result of EPA’s

action here, the Great Lakes States will

need to ensure that permits they issue

include any limitations on discharges

necessary to comply with the criteria in

today’s rule. Until actions are taken to

implement the 1995 Guidance, there

will be no economic effect of the 1995

Guidance on any entities, large or small.

States and Tribes must both adopt their

own criteria and implement them before

impacts are felt. The implementation

regulations provide States and Tribes

with a variety of flexible alternatives

which can affect the burden felt by any

small entity as a result of State or Tribal

action to implement this final rule,

including total maximum daily load

(TMDL) calculations and waste load

allocations (WLAs). Impacts will not be

felt until States and Tribes select and

put in place implementation measures.

The RFA requires analysis of the

impacts of a rule on the small entities

subject to the rules’ requirements. See

United States Distribution Companies v.

FERC, 88 F.3d 1105, 1170 (D.C. Cir.

1996). Today’s rule establishes no

requirements applicable to small

entities, and so is not susceptible to

regulatory flexibility analysis as

prescribed by the RFA. (‘‘[N]o

[regulatory flexibility] analysis is

necessary when an agency determines

that the rule will not have a significant

economic impact on a substantial

number of small entities that are subject

to the requirements of the rule,’’’ United

Distribution at 1170, quoting Mid-Tex

Elec. Co-op v. FERC, 773 F.2d 327, 342

(D.C. Cir. 1985) (emphasis added by

United Distribution court).) The Agency

is thus certifying that today’s rule will

not have a significant economic impact

on a substantial number of small

entities, within the meaning of the RFA.

Furthermore, today’s final rule results

in human health cancer criteria and

wildlife criteria less stringent than those

currently in the 1995 Guidance. If States

or Tribes adopt criteria consistent with

today’s final rule, they should reduce

any adverse economic impact that might

have been imposed by State or Tribal

adoption of the 1995 criteria.

Consequently, the economic effect of

today’s final rule relative to the 1995

Guidance should be positive. Any

adverse economic impact on small

entities associated with measures taken

to implement the current provisions of

the 1995 Guidance should be reduced

by adoption of the final revisions.

VIII. Unfunded Mandates Reform Act

Title II of the Unfunded Mandates

Reform Act of 1995 (UMRA), Public

Law 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, for proposed and final rules

with ‘‘Federal Mandates’’ that may

result in expenditures to State, local,

and Tribal governments, in the

aggregate, or to the private sector, of

$100 million or more in any one year.

Before promulgating an EPA rule for

which a written statement is needed,

section 205 of the UMRA generally

requires EPA to 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 publishes with the final

rule an explanation why that alternative

was not adopted.

Before EPA establishes any regulatory

requirements that may significantly or

uniquely affect small governments,

including Tribal governments, it must

have developed under section 203 of the

UMRA a small government agency plan.

The plan must provide for notifying

potentially affected small governments,

enabling officials of the 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.

As noted above, this final rule is

limited to the method for deriving a

composite BAF for PCBs and for

deriving a composite Kow for PCBs,

which will result in human health

cancer criteria and wildlife criteria for

PCBs less stringent than those currently

in the 1995 Guidance. If States or Tribes

adopt criteria consistent with today’s

final rule, they will reduce any adverse

economic impact that might have been

imposed by State or Tribal adoption of
Federal Register / Vol. 62, No. 48 / Wednesday, March 12, 1997 / Rules and Regulations 11731

the 1995 criteria. Consequently, EPA

has determined that this final rule

contains no regulatory requirements that

might significantly or uniquely affect

small governments. EPA has also

determined that this final rule does not

contain a Federal mandate that may

result in expenditures of $100 million or

more for State, local, and Tribal

governments, in the aggregate, or the

private sector in any one year. Thus,

today’s final rule is not subject to the

requirements of sections 202 and 205 of

the UMRA.

IX. Paperwork Reduction Act

There are no information collection

requirements in this final rule and

therefore there is no need to obtain

OMB approval under the Paperwork

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

X. References

Great Lakes Water Quality Technical

Support Document for the Procedure to

Determine Bioaccumulation Factors

(EPA–820–B–95–005). NITS Number:

PB95187290. ERIC Number: D049.

Great Lakes Water Quality Initiative

Criteria Documents for the Protection of

Human Health (EPA–820–B–95–006).

NITS Number: PB95187308. ERIC

Number: D050.

Great Lakes Water Quality Initiative

Criteria Documents for Protection of

Wildlife: DDT; Mercury; 2,3,7,8–TCDD;

PCBs (EPA–820–B–95–008). NITS

Number: PB95187324. ERIC Number:

D052.

Hawker D.W. and D.W Connell. 1988.

Octanol-Water Partition Coefficients of

Polychlorinated Biphenyl Congeners.

Environ. Sci. Technol., 22(4):382–387.

Oliver, B.G. and A.J Niimi. 1988.

Trophodynamic Analysis of

Polychlorinated Biphenyl Congeners

and Other Chlorinated Hydrocarbons in

the Lake Ontario Ecosystem. Environ.

Sci. Technol., 22(4):388–397.

U.S. Environmental Protection

Agency. Water Quality Guidance for the

Great Lakes System and Correction;

Proposed Rules. Vol. 58, No.72. April

16, 1993. pp.20802–21047.

U.S. Environmental Protection

Agency. Water Quality Guidance for the

Great Lakes System; Notice of Data

Availability. Vol. 59. August 30, 1994.

pp.44678–44685.

U.S. Environmental Protection

Agency. Final Water Quality Guidance

for the Great Lakes System; Final Rule.

Vol. 60, No.56. March 23, 1995.

pp.15366–15425.

U.S. Environmental Protection

Agency. Proposed Revisions to the

Polychlorinated Biphenyl Criteria for

Human Health and Wildlife for the

Water Quality Guidance for the Great

Lakes System; Proposed Rule. Vol. 61,

No.205. October 22, 1996. pp.54748–

54756.

List of Subjects in 40 CFR Part 132

Environmental protection,

Administrative practice and procedure,

Great Lakes, Indians—lands,

Intergovernmental relations, Reporting

and recordkeeping requirements, Water

pollution control.

Dated: March 6, 1997.

Carol M. Browner,

Administrator.

For the reasons set out in the

preamble title 40, chapter I of the Code

of Federal Regulations is amended as

follows:

PART 132—WATER QUALITY

GUIDANCE FOR THE GREAT LAKES

SYSTEM

1. The authority citation for Part 132

continues to read as follows:

Authority: 33 U.S.C. 1251 et seq.

2. Table 3 to Part 132 is amended by

revising the entry for PCBs(class) to read

as follows:

TABLE 3.—WATER QUALITY CRITERIA FOR PROTECTION OF HUMAN HEALTH

Chemical

HNV (ug/L) HCV (ug/L)

Drinking Nondrinking Drinking Nondrinking

* * * * * * *

PCBs(class) ........................................................................................................... ........................ ........................ 6.7E–6 6.7E–6

* * * * * * *

3. Table 4 to Part 132 is amended by

revising the entry for PCBs(class) to read

as follows:

TABLE 4.—WATER QUALITY CRITERIA

FOR PROTECTION OF WILDLIFE

Chemical Criteria

(ug/L)

* * * * *

PCBs(class) ................................ 1.2E–4

* * * * *

[FR Doc. 97–6215 Filed 3–11–97; 8:45 am]

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