Federal Register / Vol. 60, No. 86 / Thursday, May 4, 1995 / Rules and Regulations 22229

1 In the NTR, EPA determined compliance with

Section 303(c)(2)(B) based on the status of State

compliance as of 1991, the date of the proposed

rulemaking, and then took into account EPA

approval actions between the proposed and final

rulemaking for those States included in the

proposed rule. EPA acknowledges that, due to

subsequent State actions to delete or otherwise

modify toxics criteria (e.g., see Table 1, 57 FR

60856, December 22, 1992), all States and

Territories currently may not be in full compliance

with Section 303(c)(2)(B).

2 Interim Guidance on Interpretation and

Implementation of Aquatic Life Criteria for Metals,

Continued

affecting a sector of the economy,

productivity, competition, jobs, the

environment, public health or safety, or

State, local, or tribal governments or

communities (also known as

‘‘economically significant’’); (2) creating

serious inconsistency or otherwise

interfering with an action taken or

planned by another agency; (3)

materially altering the budgetary

impacts of entitlements, grants, user

fees, or loan programs; or (4) raising

novel legal or policy issues arising out

of legal mandates, the President’s

priorities, or the principles set forth in

this order. Pursuant to the terms of this

order, EPA has determined that this stay

would not be ‘‘significant’’.

B. Regulatory Flexibility Act

Under the Regulatory Flexibility Act,

5 U.S.C. 601 et seq., EPA is certifying

that a stay of these criteria would not

have a significant impact on a

substantial number of small businesses.

C. Paperwork Reduction Act

There are no information collection

requirements associated with this

administrative stay covered under the

provisions of the Paperwork Reduction

Act of 1980, 44 U.S.C. 3501 et seq.

List of Subjects in 40 CFR Part 131

Environmental protection, Water

pollution control, Water quality

standards, Toxic pollutants.

Dated: April 14, 1995.

Carol M. Browner,

Administrator.

For the reasons set out in the

preamble, part 131 of title 40 of the

Code of Federal Regulations is amended

as follows:

PART 131—[AMENDED]

1. The authority citation for part 131

continues to read as follows:

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

2. Part 131 is amended by adding at

the end of § 131.36(b)(1) the following

‘‘Note to paragraph (b)(1)’’:

§ 131.36 Toxics criteria for those States

not complying with Clean Water Act Section

303(c)(2)(B).

* * * * *

(b)(1) * * *

Note to paragraph (b)(1): On April 14,

1995, the Environmental Protection

Agency issued a stay of certain criteria

in paragraph (b)(1) of this section as

follows: the criteria in columns B and C

for arsenic, cadmium, chromium (VI),

copper, lead, nickel, silver, and zinc; the

criteria in B1 and C1 for mercury; the

criteria in column B for chromium (III);

and the criteria in column C for

selenium. The stay remains in effect

until further notice.

[FR Doc. 95–10147 Filed 5–3–95; 8:45 am]

BILLING CODE 6560–50–P

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 131

[WH–FRL–5196–1]

Water Quality Standards;

Establishment of Numeric Criteria for

Priority Toxic Pollutants; States’

Compliance—Revision of Metals

Criteria

AGENCY: Environmental Protection

Agency (EPA).

ACTION: Interim final rule, notice of data

availability and request for comments.

SUMMARY: EPA is promulgating new

aquatic life metals criteria for nine

States, Puerto Rico, and the District of

Columbia, that are subject to EPA’s 1992

National Toxics Rule (‘‘NTR’’). These

new metals criteria reflect EPA’s current

policy for setting water quality criteria

for metals. This interim final rule

establishes metals criteria that are

protective of aquatic life and

approximate, better than the 1992

criteria, the biologically available

fraction of water borne metals to aquatic

organisms. Use of the new metals

criteria will allow permitting authorities

in the nine States, Puerto Rico and the

District of Columbia, to establish

effluent limitations based on the new

metals criteria rather than the 1992

criteria which EPA now considers to be

more stringent than may be necessary to

protect designated uses for aquatic life.

The interim final rule will be in effect

while EPA considers public comments

and develops a final rule. This rule

terminates the Administrative Stay

published elsewhere in this issue of the

Federal Register.

DATES: This interim final rule is

effective April 15, 1995. Comments on

the interim final rule and other data

noticed in this preamble will be

accepted until July 3, 1995.

ADDRESSES: An original and 3 copies of

all comments and references on the

interim final rule and data should be

addressed to: Revision of the National

Toxics Rule-Dissolved Metals Criteria,

Comment Clerk; Water Docket (MC–

4101), U.S. Environmental Protection

Agency, 401 M Street SW., Washington,

DC 20460. The administrative record for

this rulemaking is available for review

and copying at the Environmental

Protection Agency, Office of Water

Docket, 401 M Street SW, Washington

DC, 20460, Room L102, on weekdays

during EPA’s normal business hours of

8 a.m. until 4:30 p.m. For access to the

Docket materials, call (202) 260–3027

between 9:00a.m.–3:30p.m., for an

appointment. A reasonable fee will be

charged for photocopies.

FOR FURTHER INFORMATION CONTACT:

Timothy J. Kasten, telephone 202–260–

5994.

SUPPLEMENTARY INFORMATION:

A. General Background

1. Regulatory Background

In the NTR, EPA promulgated

numeric water quality criteria for 12

States, Puerto Rico, and the District of

Columbia, that failed to comply fully

with Section 303(c)(2)(B) of the Clean

Water Act. (57 FR 60848, December 22,

1992 codified in the Code of Federal

Regulations at 40 CFR 131.36).1 Those

criteria became the legally enforceable

water quality standards in the named

States, Puerto Rico, and the District of

Columbia, for all purposes and

programs under the Clean Water Act on

February 5, 1993. Included among the

water quality criteria promulgated in the

NTR were numeric criteria for the

protection of aquatic life for 11 metals:

arsenic, cadmium, chromium (III),

chromium (VI), copper, lead, mercury,

nickel, selenium, silver, and zinc.

The Agency received extensive public

comment during the development of the

NTR regarding the most appropriate

approach for expressing the metals

criteria. The principal issue was the

correlation between metals that are

measured and metals that are

bioavailable and toxic to aquatic life.

2. Policy on Aquatic Life Metals Criteria

At the time of the NTR promulgation,

Agency policy was to express metals

criteria, as recommended in its Section

304(a) criteria documents, as total

recoverable metal measurements.

Agency guidance prior to the NTR

promulgation indicated that metals

criteria may be expressed either as total

recoverable metal or dissolved metal.2
22230 Federal Register / Vol. 60, No. 86 / Thursday, May 4, 1995 / Rules and Regulations

U.S. EPA, May 1992. (Notice of availability

published at 57 FR 24041, June 5, 1992.)

3See Interim Guidance on the Determination and

Use of Water-Effect Ratios for Metals, February

1994, EPA 823–B–94–001.

Because the NTR was to cover a

substantial number of water bodies of

varying water quality, EPA selected

what it considered the simplest, more

conservative approach and the approach

reflected in its criteria documents, to

implement the metals criteria, namely

the total recoverable method.

Accordingly, the metals criteria

promulgated in the NTR were expressed

as total recoverable metals, although

EPA also provided for site-specific

criteria development.3

Thereafter, EPA continued to work

with States and other interested parties

on the issue of metals bioavailability

and toxicity. EPA held a workshop of

invited experts on this issue; the results

of the consultations were published at

58 FR 32131, June 8, 1993. As a result

of these consultations, the Agency

issued a policy memorandum on

October 1, 1993, entitled: Office of

Water Policy and Technical Guidance

on Interpretation and Implementation of

Aquatic Life Metals Criteria (‘‘Metals

Policy’’). (The complete October 1, 1993

memorandum can be obtained from

EPA’s Office of Water Resource Center

(202) 260–7786 or the Office of Water

Docket.) The Metals Policy states:

It is now the policy of the Office of Water

that the use of dissolved metal to set and

measure compliance with water quality

standards is the recommended approach,

because dissolved metal more closely

approximates the bioavailable fraction of

metal in the water column than does total

recoverable metal.

It further states:

Until the scientific uncertainties are better

resolved, a range of different risk

management decisions can be justified. EPA

recommends that State water quality

standards be based on dissolved metal. EPA

will also approve a State risk management

decision to adopt standards based on total

recoverable metal, if those standards are

otherwise approvable as a matter of law. (See

Section 510, Federal Water Pollution Control

Act, Public Law 100–4, 33 U.S.C. 466 et seq.)

The adoption of the Metals Policy did

not change the Agency’s position that

the existing total recoverable criteria

published under Section 304(a) of the

Clean Water Act continue to be

scientifically defensible. EPA developed

the total recoverable criteria using highquality analytical data and are still

scientifically defensible criteria. When

developing and adopting its own

standards, a State, in making its risk

management decision, may wish to

consider sediment, food chain effects

and other fate-related issues and decide

to adopt total recoverable or dissolved

metals criteria.

In general, EPA continues to conduct

research on metals toxicity to further

refine the criteria and their

implementation. However, the aim of

both the Clean Water Act and EPA

policy is that a more effective way of

incorporating new science into the

water quality program is for the States

to promulgate their own standards and

implementation policies. The States can

then make appropriate updates, rather

than relying on Federal promulgations

such as today’s rule.

3. Litigation and Settlement of NTR

Metals Issues

A number of parties brought lawsuits

challenging the NTR metals criteria. See

American Forest and Paper Ass’n, Inc.

et al. v. EPA, Consolidated case No. 93–

0694 RMU (D.D.C.) The Plaintiffs in

those lawsuits wanted the permitting

authorities in the NTR States to use

criteria based on dissolved metal rather

than total recoverable. After careful

consideration of the issue, EPA

concluded that it was in the public

interest to revise the metals criteria

promulgated in the NTR to reflect the

Office of Water’s new metals policy. On

February 15, 1995, EPA and the

Plaintiffs filed a partial settlement

agreement with the court. Pursuant to

the terms of the partial settlement

agreement, EPA agreed to issue an

administrative stay of the numeric

aquatic life water quality criteria

(expressed as total recoverable metal)

for: arsenic, cadmium, chromium (III),

chromium (VI), copper, lead, mercury

(acute only), nickel, selenium (saltwater

only), silver, and zinc. That stay is

published in a separate notice in today’s

Federal Register. The stay is intended to

be in effect only until EPA takes action

to amend the NTR by promulgating new

metals criteria based on dissolved metal.

With today’s interim final rule, EPA is

promulgating new metals criteria for

those metals listed in the stay based on

dissolved metal and therefore this

action will supersede the administrative

stay.

B. Today’s Interim Final Rule

EPA’s action today revises the NTR

that established numeric aquatic life

metals criteria for 9 States, Puerto Rico

and the District of Columbia (Table 1).

(Of the 12 NTR States, aquatic life

metals criteria were only promulgated

for nine.) The numeric criteria in

today’s rule reflect the Office of Water’s

current policy with respect to metals.

This action promulgates dissolved

metals criteria for those total

recoverable metals criteria subject to the

Agency’s administrative stay.

TABLE 1.—STATES SUBJECT TO THE

REVISED METALS CRITERIA 1

Alaska

Arkansas

California

Idaho

Kansas

Michigan

New Jersey

Vermont

Washington

District of Columbia

Puerto Rico

1Today’s interim final rule may have differing applicability

for each of the States in this table depending on the State’s

individual compliance with Section 303(c)(2)(B) of the Clean

Water Act. See 40 CFR 131.36(d) for State applicability.

C. Conversion Factors: Total

Recoverable to Dissolved Metal

Because EPA’s Section 304(a) criteria

are expressed as total recoverable metal,

to express the criteria as dissolved,

application of a conversion factor is

necessary to account for the particulate

metal present in the laboratory toxicity

tests used to develop the total

recoverable criteria. Initially, EPA

included a set of recommended

freshwater conversion factors with the

Metals Policy. Based on additional

laboratory evaluations that simulated

the original toxicity tests, EPA has

refined the procedures used to develop

freshwater conversion factors for aquatic

life criteria. EPA made new conversion

factors available for public comment in

the context of EPA’s Proposed Guidance

for the Great Lakes System on August

30, 1994, at 59 FR 44678.

EPA has also conducted saltwater

laboratory simulation tests for the

development of conversion factors for

saltwater metals criteria. The saltwater

simulation tests were conducted using

the same methodology as the freshwater

tests with minor modifications,

necessary to account for saltwater. The

saltwater test results are being made

available with today’s rule. The

conversion factors in this rule and other

technical reports referenced herein,

supersede the conversion factors

presented in Attachment #2 of the

Metals Policy.

Total recoverable to dissolved metal

conversion factors were attached to the

partial settlement agreement in the form

of a draft guidance entitled, Guidance to

States Subject to the National Toxics

Rule For Setting NPDES Limits During

the Stay of the Metals Criteria. (The

partial settlement agreement is available

from the Water Docket.) The draft

guidance used data that were available

through December 21, 1994. The
Federal Register / Vol. 60, No. 86 / Thursday, May 4, 1995 / Rules and Regulations 22231

conversion factors presented in today’s

rule reflect the best science available to

EPA at the time of promulgation and

contain minor modifications from those

in the attachment to the February 15

partial settlement agreement. For each

metal specific conversion factor, the

changes between the draft guidance and

today’s rule are less than 10%. EPA has

determined these changes to be minor.

1. Freshwater Criteria Conversion

Factors

The final freshwater conversion

factors used in today’s rule are

contained in: ‘‘Derivation of Conversion

Factors for the Calculation of Dissolved

Freshwater Aquatic Life Criteria for

Metals’’ (U.S. EPA, 1995), available from

the Water Docket and are presented in

Table 2 below. This study did not

include laboratory simulation tests for

mercury or silver, therefore, the

freshwater conversion factors for

mercury and silver used today are from

the Metals Policy.

The conversion factors for most

freshwater metals were established as

constant values. For cadmium and lead

however, EPA found that water

hardness mediated the conversion factor

and should be taken into account when

converting total recoverable cadmium

and lead criteria to dissolved. Table 2

presents the hardness-dependent

conversion factors for cadmium and

lead. The hardness-dependent

conversion factor for lead was included

in the August 30, 1994 Notice of

Availability (59 FR 44678). In today’s

action, EPA is specifically requesting

comment on the use of hardnessdependent conversion factor for

cadmium.

TABLE 2.—FRESHWATER CRITERIA

CONVERSION FACTORS FOR DISSOLVED METALS

Metal

Conversion factors a

Acute Chronic

Arsenic ...................... 1.000 1.000

Cadmium b ................. 0.944 0.909

Chromium (III) ........... 0.316 0.860

Chromium(VI) ............ 0.982 0.962

Copper ...................... 0.960 0.960

Lead b ........................ 0.791 0.791

Mercury ..................... c 0.85 d N/A

Nickel ........................ 0.998 0.997

Silver ......................... c 0.85 e N/A

Zinc ........................... 0.978 0.986

aThe conversion factors are given to three

decimal places because they are intermediate

values in the calculation of dissolved criteria. b Conversion factors are hardness-dependent. The values shown are with a hardness of

100 mg/L as calcium carbonate (CaCO3).

Conversion factors (CF) for any hardness can

be calculated using the following equations:

Cadmium

Acute: CF=1.136672-[(ln hardness)

(0.041838)]

Chronic: CF=1.101672-[(ln hardness)

(0.041838)]

Lead (Acute and Chronic): CF=1.46203-[(ln

hardness)(0.145712)]

c Conversion factor from: Office of Water

Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals

Criteria, October 1, 1993. Factors were expressed to two decimal places. d CCC for mercury cannot be converted to

dissolved, because it is based on mercury residues in aquatic organisms rather than toxicity. e Not applicable, EPA has not published final

chronic criteria values for silver.

2. Saltwater Criteria Conversion Factors

Acute saltwater conversion factors are

being made available through today’s

rule. The data and the acute criteria

conversion factors for saltwater are

contained in: ‘‘Derivation of Conversion

Factors for the Calculation of Dissolved

Saltwater Aquatic Life Criteria for

Metals’’ (U.S. EPA 1995). This summary

report and its supporting data are

available from the Water Docket.

Saltwater chronic conversion factors

have not been developed separately and

therefore are not available for today’s

rule. Based on close similarities

between the freshwater acute and

chronic conversion factors, EPA

believes that, if calculated, the chronic

saltwater conversion factors would be

nearly the same as the acute saltwater

factors. In the absence of these chronic

conversion factors, the saltwater acute

conversion factors will apply. The

saltwater conversion factors are

presented in Table 3 below. Saltwater

simulation tests were not completed for

mercury or silver, therefore the

conversion factors from the Metals

Policy will continue to apply.

TABLE 3.—SALTWATER CRITERIA CONVERSION FACTORS FOR DISSOLVED

METALS

Metal

Conversion factors a

Arsenic ............................................ 1.000

Cadmium ........................................ 0.994

Chromium (III) ................................. (d)

Chromium (VI) ................................ 0.993

Copper ............................................ 0.83

Lead ................................................ 0.951

Mercury ........................................... b c 0.85

Nickel .............................................. 0.990

Selenium ......................................... 0.998

Silver ............................................... b 0.85

Zinc ................................................. 0.946

a Conversion factors on this table were calculated for acute criteria only. Conversion factors for chronic criteria are not currently available. In the absence of chronic conversion

factors saltwater acute conversion factors are

used.

b Conversion factor from: Office of Water

Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals

Criteria, October 1, 1993. Factors were expressed to two decimal places. c CCC for mercury cannot be converted to

dissolved, because it is based on mercury residues in aquatic organisms rather than toxicity. d No saltwater criteria.

D. Applicability Requirements for

Metals Criteria

Through today’s action, EPA is also

requesting comments on the

applicability requirements in 40 CFR

131.36(c) as they apply to the metals

criteria. In particular, EPA is requesting

comments on § 131.36(c)(4)(i) regarding

the calculation of hardness-dependent

freshwater metals criteria. Section

131.36(c)(4)(i) describes the minimum

and maximum hardness values (25 mg/

L and 400 mg/L as CaCO3, respectively)

to be used when calculating hardnessdependent freshwater metals criteria.

This requirement is not changed by

today’s interim final rule, however EPA

is requesting comment on an alternative

approach. Most of the data used to

develop these hardness formulas were

in the hardness range of 25 mg/L to 400

mg/L as CaCO3. The formulas are

therefore most accurate in this range.

Using a hardness of 25 mg/L for

calculating criteria, when the actual

ambient hardness is less than 25 mg/L,

could result in criteria that are underprotective of aquatic life. EPA is

therefore requesting comments on the

use of the actual ambient hardness for

calculating criteria when the hardness is

below 25 mg/L as CaCO3.

Most freshwaters of the U.S. have an

ambient hardness of less than 400 mg/

L as CaCO3. Using 400 mg/L to calculate

criteria, for waters with an ambient

hardness of greater than 400 mg/L, may

result in over-protective criteria because

at a hardness above 400 mg/L, other

confounding factors, which may cause

this hardness, can also affect the

toxicity. EPA is requesting comment on

an approach that would make two

options available for calculating metals

criteria for waters with a hardness of

greater than 400 mg/L as CaCO3: Option

1—use 400 mg/L as CaCO3 for the

criteria calculation or, Option 2—use

the actual hardness and require the use

of the water-effect ratio to modify the

final criteria value to more accurately

reflect ambient conditions. (EPA notes

that in the NTR States, the use of the

water-effect ratio is assigned a value of

1.0, unless otherwise specified by the

permitting authority. See 40 CFR

131.36(c)(4)(iii).)
22232 Federal Register / Vol. 60, No. 86 / Thursday, May 4, 1995 / Rules and Regulations

E. Calculation of Dissolved Metals

Criteria

Metals criteria values in 40 CFR

131.36(b)(1), as amended today, are now

shown as dissolved metal. These criteria

have been calculated in one of two

ways. For freshwater metals criteria that

are hardness-dependent (denoted by

footnote ‘‘e’’ in the matrix), the

dissolved metal criteria value must be

calculated separately for each hardness

using the table at § 131.36(b)(2), as

amended today. The hardnessdependent freshwater criteria values

presented in the matrix at § 131.36(b)(1)

have been calculated using a hardness

of 100 mg/L CaCO3 for comparative

purposes only. Saltwater metals criteria

and freshwater criteria that are not

hardness-dependent (criteria denoted by

footnote ‘‘m’’ in the matrix) are

calculated by taking the total

recoverable criteria values (from EPA

National Ambient Water Quality Criteria

Documents) before rounding, and

multiplying them by the appropriate

conversion factors from Table 2 or 3 of

Section C of this preamble. (The total

recoverable criteria values are shown to

four figures, where available, because

they are intermediate values in the

calculation of dissolved metals criteria.)

The final dissolved metals criteria

values, as they appear in the matrix at

§ 131.36(b)(1), are rounded to two

significant figures. Tables 4a and 4b

below, summarize the conversions for

saltwater criteria and freshwater criteria

that are not hardness-dependent.

EPA notes that if a non-NTR State

adopts standards, or an NTR State

adopts its own standards (for

subsequent withdrawal from the NTR),

it may prefer a more conservative

approach and adopt total recoverable

metals criteria. In doing so, the State

may use EPA’s total recoverable criteria

from Tables 4a and 4b (rounded to two

significant figures) or, for hardnessdependent freshwater criteria, omit the

conversion factor from the formula

presented in § 131.36(b)(2).

Tables 4a and 4b use the following

abbreviations and formulas for

calculating dissolved metals criteria

(CMC and CCC are defined in 40 CFR

131.36(b)(1), footnote d):

CMC—Criterion Maximum

Concentration

CCC—Criterion Continuous

Concentration

CF—Conversion Factor

Formulas for Calculating Dissolved

Metals Criteria:

CMCdissolved = CMCtotal recoverable × Acute

CF

CCCdissolved = CCCtotal recoverable × Chronic

CF

TABLE 4a.—CALCULATION OF FRESHWATER DISSOLVED METALS CRITERIA THAT ARE NOT HARDNESS-DEPENDENT

METAL

Total Recoverable Metals

Criteria 1 (μg/L)

Conversion factors 2 Dissolved metals criteria 3

CMC CCC Acute Chronic CMC CCC

Arsenic ...................................................................... 359.1 188.9 1.000 1.000 360 190

Chromium(VI) ........................................................... 15.74 10.80 0.982 0.962 15 10

Mercury ..................................................................... 2.428 0.0122 0.85 N/A 2.1 N/A

1From EPA National Ambient Water Quality Criteria Documents.

2From Table 2.

3Final dissolved metals criteria have been rounded to two significant figures.

TABLE 4b.—CALCULATION OF SALTWATER DISSOLVED METALS CRITERIA

Metal

Total recoverable metals criteria 1 (μg/L)Conversion factors 2 Dissolved metals criteria 3

CMC CCC Acute Chronic CMC CCC

Arsenic .................................................................. 68.55 36.05 1.000 1.000 69 36

Cadmium .............................................................. 42.54 9.345 0.994 0.994 42 9.3

Chromium (III) ....................................................... N/A4 N/A4 N/A4 N/A4 N/A4 N/A4

Chromium (VI) ...................................................... 1079 49.86 0.993 0.993 1100 50

Copper .................................................................. 2.916 2.916 0.83 0.83 2.4 2.4

Lead ...................................................................... 217.16 8.468 0.951 0.951 210 8.1

Mercury ................................................................. 2.062 .0250 0.85 N/A5 1.8 N/A5

Nickel .................................................................... 74.60 8.293 0.990 0.990 74 8.2

Selenium ............................................................... 293.8 70.69 0.998 0.998 290 71

Silver ..................................................................... 2.3 N/A4 0.85 N/A4 1.9 N/A4

Zinc ....................................................................... 95.10 86.14 0.946 0.946 90 81

1From EPA National Ambient Water Quality Criteria Documents.

2From Table 3.

3Final dissolved metals criteria have been rounded to two significant figures.

4 Not applicable, national criteria not available.

5The CCC for mercury is expressed as total recoverable.

F. Site-Specific Criteria Modifications

EPA has issued guidance (Water

Quality Standards Handbook, Second

Edition-1993, EPA–823–B–93–002 and

update #1, EPA–823–B–94–006, August

1994, at page 3–38 and Appendix L),

describing three site-specific criteria

development methodologies:

recalculation procedure, indicator

species procedure (also known as the

water-effect ratio (WER)) and resident

species procedure. Only the first two of

these have been widely used.

In the NTR, EPA identified the WER

as the method for optional site-specific

criteria development for certain metals.

On February 22, 1994, EPA issued

Interim Guidance on the Determination

and Use of Water-Effect Ratios for

Metals, EPA 823–B–94–001, now

incorporated into the updated Second

Edition of the Water Quality Standards

Handbook, Appendix L. In accordance

with the WER guidance and where

application of the WER is deemed
Federal Register / Vol. 60, No. 86 / Thursday, May 4, 1995 / Rules and Regulations 22233

appropriate, EPA strongly encourages

the application of the WER on a

watershed or waterbody basis as

opposed to application on a dischargerby-discharger basis. This approach is

technically sound, an efficient use of

resources, and allowable for permitting

authorities under the NTR.

EPA’s endorsement of the use of the

WER is not affected by today’s rule. As

noted in the NTR at 57 FR 60879, the

WER is a more comprehensive

mechanism for addressing

bioavailability issues than simply

expressing the criteria in terms of

dissolved metal. Consequently,

expressing the criteria in terms of

dissolved metal, as done in today’s rule,

does not completely eliminate the

utility of the WER. This is particularly

true for copper, a metal that forms

reduced-toxicity complexes with

dissolved organic matter.

The Interim Guidance on

Determination and Use of Water-Effect

Ratios for Metals, Appendix D, explains

the relationship between WERs for

dissolved criteria, and WERs for total

recoverable criteria. Dissolved

measurements are to be used in the sitespecific toxicity testing underlying the

WERs for dissolved criteria. Because

WERs for dissolved criteria generally are

little affected by elevated particulate

concentrations, EPA expects those

WERs to be somewhat less than WERs

for total recoverable criteria in such

situations. Nevertheless, after the sitespecific ratio of dissolved to total metal

has been taken into account, EPA

expects a permit limit derived using a

WER for a dissolved criterion to be

similar to the permit limit that would be

derived from the WER for the

corresponding total recoverable

criterion.

Because WERs for dissolved criteria

generally are little affected by

particulate concentrations, those WERS

also may often exhibit less time

variability than WERs for total

recoverable criteria. Consequently,

WER-adjusted dissolved criteria may

have somewhat greater certainty than

WER-adjusted total recoverable criteria.

EPA expects the use of WERs for

dissolved criteria to provide the same

level of protection as the use of WERs

for total recoverable criteria in the NTR.

However, the increased reliability of the

dissolved criteria prior to WER

adjustment (compared to the total

recoverable criteria unadjusted) will

reduce the need for site-specific WER

determinations.

G. Technical Guidance

EPA continues to urge the States

affected by this rule to adopt their own

standards and negate the need for

Federal action. Should a State choose to

adopt dissolved criteria, EPA

recommends use of the Metals Policy,

its attachments (as updated herein) and

other guidance referenced in this

preamble for implementation of

dissolved metals criteria. Attachments

to the Metals Policy include: guidance

on dynamic modeling and translators

(Attachment #3), and clean analytical

techniques and monitoring (Attachment

#4). Additional guidance on clean and

ultra-clean techniques is available and

under development (see discussion

below). EPA will continue to update

implementation guidance as needed in

the future.

1. Total Maximum Daily Loads (TMDLs)

and National Pollutant Discharge

Elimination System (NPDES) Permits

EPA’s NPDES regulations require that

limits for metals in permits be stated as

total recoverable in most cases {see 40

CFR § 122.45(c)} except when an

effluent guideline specifies the

limitation in another form of the metal,

the approved analytical methods

measure only dissolved metal, or the

permit writer expresses a metal’s limit

in another form (e.g., dissolved, specific

valence, or total) when required to carry

out provisions of the Clean Water Act.

This is because the chemical conditions

in ambient waters frequently differ

substantially from those in the effluent

and there is no assurance that effluent

particulate metal would not dissolve

after discharge. The NPDES permit

regulations do not require that State

water quality standards be expressed as

total recoverable; rather, the regulations

require permit writers to develop permit

limits that are expressed in terms of

metals concentrations and loadings that

are measured using the total recoverable

method. Expressing criteria as dissolved

metal requires translation between

different metal forms in the calculation

of the permit limit so that a total

recoverable permit limit can be

established that will achieve water

quality standards. Both the TMDL and

NPDES permit use of water quality

criteria in NTR States now require the

ability to translate between dissolved

metal in ambient waters and total

recoverable metal in effluents. In

addition to the guidance on dynamic

modeling and translators attached to the

Metals Policy, EPA’s Interim Guidance

on the Determination and Use of WaterEffect Ratios for Metals, February 1994,

EPA 823–B–94–001 (pages 116 and 128–

130), presents an effluent-specific

approach for calculating a total

recoverable metal permit limit from a

dissolved metal criterion. EPA is

expecting to complete additional

guidance on translators in 1995.

2. Monitoring

a. Use of Clean Sampling and Analytical

Techniques

In assessing waterbodies to determine

the potential for toxicity problems due

to metals, the quality of the data used

is an important issue. Depending on the

concentration of metal present, the use

of ‘‘clean’’ and ‘‘ultra-clean’’ techniques

for sampling and analysis may be

critical to accurate data for

implementation of aquatic life criteria

for metals.

‘‘Clean’’ techniques refer to those

requirements (or practices for sample

collection and handling) necessary to

produce reliable analytical data in the

microgram per liter (μg/L) or part per

billion (ppb) range. ‘‘Ultra-clean’’

techniques refer to those requirements

or practices necessary to produce

reliable analytical data in the nanogram

per liter (ng/L) or part per trillion (ppt)

range. Because typical concentrations of

metals in surface waters and effluents

vary from one metal to another, the

effect of contamination on the quality of

metals monitoring data varies

appreciably.

EPA has developed protocols on the

use of clean techniques in coordination

with the United States Geological

Survey (USGS). The guidance, entitled

Method 1669: Sampling Ambient Water

for Determination of Trace Metals at

EPA Water Quality Criteria Levels is

available from the Office of Water

Resource Center as part of the Trace

Metals Package. Draft protocols for

ultra-clean techniques will be available

in late calendar year 1995.

H. Saltwater Copper Criteria

The saltwater copper criteria in

today’s interim final rule are 2.4 μg/L

dissolved copper for both CMC and CCC

based on conversion of 2.9 μg/L for both

the CMC and CCC from total recoverable

to dissolved metal. New data collected

from a study for the New York/New

Jersey Harbor indicate the potential

need to revise the copper criteria

document to reflect a change in the

saltwater CMC and CCC aquatic life

values. A comprehensive literature

search was conducted and toxicity test

data for seven new species were added

to the database for the saltwater copper

criteria. EPA believes these new data

have national implications and indicate

the national criteria may be more

accurate at a CMC of 4.8 μg/L dissolved

and a CCC of 3.1 μg/L dissolved. In

today’s rulemaking, EPA is noticing the

availability of data to support these
22234 Federal Register / Vol. 60, No. 86 / Thursday, May 4, 1995 / Rules and Regulations

potential changes in the national

saltwater copper criteria and solicits

comments. The data can be found in the

draft document entitled, Ambient Water

Quality Criteria—Copper, Addendum

1995. This document is available from

the Office of Water Resource Center or

Water Docket. Based on those

comments, the saltwater copper criteria

in this interim final rule may be revised

in the final rule to reflect these new

data.

I. Procedural Requirements

Section 553 of the Administrative

Procedure Act provides that when an

agency, for good cause, finds that notice

and public procedure are impracticable,

unnecessary or contrary to the public

interest, it may first issue a rule without

providing notice and an opportunity to

comment. EPA has concluded that there

is good cause to issue this interim final

rule without notice and comment and to

make the rule effective immediately.

In 1987, Congress amended the Clean

Water Act to provide that States must

adopt numeric criteria to control the

discharge of toxic pollutants. Before this

requirement was enacted, few States

had adopted numeric criteria for toxic

pollutants and had to rely on

‘‘narrative’’ criteria (e.g., ‘‘free from

toxics in toxic amounts’’) to set

discharge limits for such pollutants.

Congress, expressing concern over the

calculation of discharge limitations for

toxics without numeric criteria,

required States to adopt numeric,

pollutant-specific criteria for toxic

pollutants (56 FR 58423–58424, Nov.

19, 1991).

Following promulgation of the NTR,

EPA continued to evaluate available

information on metals. EPA held a

public meeting of experts in which a

recommendation was made to express

the ambient water criteria as dissolved

metal. This recommendation and others,

were noticed for public comment at 58

FR 32131, June 8, 1993. It is EPA’s

judgment that aquatic life criteria for

metals, when expressed as dissolved

metal provide a more accurate

measurement of metals bioavailability to

organisms in the water column than

when expressed as total recoverable

metal. Thus, in some situations, the

total recoverable metals criteria in the

NTR may result in permit limits that are

more stringent than if the criteria were

expressed in a dissolved form. As a

result, in these situations, permitting

authorities in the NTR States may be

imposing more stringent (and

potentially more costly) effluent

limitations on their dischargers than

will be required to meet the new

dissolved metals aquatic life criteria put

in place today.

EPA considered the impacts of a stay

of the current metals criteria while it

undertook a standard rulemaking (i.e.,

proposed rule followed by a final) to

revise the aquatic life metals criteria to

express them in a dissolved form.

However, during the effective period of

the stay (the interim between proposal

and final rule), permitting authorities

for the NTR States would generally need

to use the States’ narrative criteria (e.g.,

free from toxics in toxic amounts) to

develop permit limits for the discharge

of toxics. Because the Congressional

directive is clear that States must have

numeric criteria for toxic pollutants,

EPA rejected this approach in favor of

an interim final rule.

By today’s action the Agency upholds

the intent of § 303(c)(2)(B) of the Clean

Water Act and avoids the need for

permitting authorities to rely on

narrative criteria to develop permit

limits. Further, this interim final rule is

a temporary measure. The Agency notes

that considerable public comment has

already been obtained on the Metals

Policy and the specific criteria being

issued in this interim final rule. EPA

held a meeting with invited experts in

January 1993 in Annapolis, Maryland to

further elicit comment on the use of

dissolved metals for developing national

metals criteria. The Agency solicited

comments on the recommendations

made by presenters at that meeting in

the Federal Register on July 9, 1993 (58

FR 32131). The Metals Policy issued in

October 1993 has received wide-spread

distribution and informal response from

many interested parties. In August 1994,

EPA issued a Federal Register notice

indicating that the Agency was

considering the use of the Metals Policy

to develop metals criteria in the Great

Lakes Initiative (59 FR 44678, August

30, 1994) and comments were received

on this issue. Today’s action has the

additional benefit of the comments

received from the August 1994 notice on

the Great Lakes Initiative.

EPA therefore concludes that public

comment on this interim measure is

unnecessary because ample comment

has already been received on the

numeric dissolved metals criteria and

additional comment is being solicited

and will be considered before a final

rule is issued. Further, a public

comment process before adopting the

new metals criteria is contrary to the

public interest because: 1) the current

metals criteria place a potentially

unnecessary regulatory burden on

dischargers in the States covered by this

rule, without necessarily providing

additional protection to aquatic life in

the water column and 2) it is in the

public interest for the States to have

numeric criteria protective of aquatic

life.

Because of the potential adverse effect

on public interest noted above, the

Agency has determined there is good

cause for making this regulation

effective immediately.

J. Regulatory Assessment Requirements

1. Unfunded Mandates Reform Act of

1995

Section 201 of the Unfunded

Mandates Reform Act of 1995

(‘‘Unfunded Mandates Act’’), signed

into law on March 22, 1995, requires

each Agency, unless prohibited by law,

to assess the effects of Federal

regulation on State, local and tribal

governments and the private sector

under section 202 of the Act. EPA must

prepare a written statement to

accompany any rules where the

estimated costs to State, local and tribal

governments, in the aggregate, or to the

private sector will be $100 million or

more in any one year. Under section

205, for rules that require a written

statement under section 202, EPA must

select the most cost-effective and least

burdensome alternative that achieves

the objective of such a rule and that is

consistent with statutory requirements.

Also, for such rules, section 203

requires EPA to establish a plan for

informing and advising any small

governments that may be significantly

and uniquely affected by the rule.

EPA estimates that the costs to State,

local, and tribal governments, or to the

private sector, from today’s interim final

rule will not be $100 million or more.

EPA has determined that this rule

should reduce current regulatory

requirements imposed by the NTR. By

promulgating the metals criteria in the

NTR as dissolved metals, rather than

total recoverable, EPA is reducing

potential costs to discharge permittees

and other parties subject to the water

quality criteria. Therefore, an unfunded

mandates statement pursuant to section

202 is not necessary.

While an unfunded mandates

statement is not necessary for this rule,

EPA notes that it has previously

considered the costs and benefits of

promulgating Federal water quality

criteria when the Agency issued the

NTR in 1992. See 57 FR 60903–60909

(December 22, 1992). That analysis

would continue to be relevant with

respect to this issue of costs and benefits

arising from Federal promulgation of

criteria for states. Of course, to the

extent today’s interim final rule is

putting in place less burdensome
Federal Register / Vol. 60, No. 86 / Thursday, May 4, 1995 / Rules and Regulations 22235

requirements than the 1992 rule, the

Agency is reducing any potential costs.

It is important to note that the Federal

criteria in today’s rule, as the Federal

criteria in the 1992 rule, only impose

requirements until the States adopt, and

EPA approves, criteria meeting the

requirements of section 303(c)(2)(B) of

the Clean Water Act. EPA continues to

work with the States to assist them in

adopting their own criteria thereby

enabling EPA to withdraw the Federal

criteria.

While section 205 of the Unfunded

Mandates Act is not applicable to

today’s rule because the rule does not

require a written statement under

section 202, the Agency does believe

that today’s rule is consistent with the

intent of section 205. Section 205

directs agencies to consider regulatory

alternatives and to select the least

costly, most cost-effective or least

burdensome alternative that achieves

the objectives of the rule. EPA’s

decision to promulgate metals criteria

expressed as dissolved rather than total

recoverable represents the Agency’s

selection of the least costly, most costeffective and least burdensome

alternative for setting metals criteria.

The Agency addressed this issue in

detail in the development of the Great

Lakes Water Quality Guidance,

promulgated on March 13, 1995 (60 FR

15366, March 23, 1995). For today’s rule

the Agency was obligated pursuant to

section 303 to promulgate water quality

criteria for states not in compliance with

section 303(c)(2)(B). Today’s rule

achieves that objective consistent with

the intent of section 205.

Finally, because today’s rule relieves

a regulatory requirement, EPA does not

believe that the rule will establish

requirements that might significantly or

uniquely affect small governments

within the meaning of section 203.

However, the Agency is committed to

working with affected small

governments by providing notice of

requirements that might potentially

affect them, enable them to provide

meaningful and timely input, and to

inform, educate and advise small

governments on compliance with any

requirements. With respect to today’s

interim final rule, representatives of

State and local governments

participated in the development of, and

provided comments to the Office of

Water’s current metals policy. The

Agency recognizes the importance of

soliciting the input of small

governments and will be available to

work with them to address any issues

related to compliance with today’s rule.

2. Executive Order 12866

Under Executive Order 12866 (56 FR

51735, October 4, 1993), the Agency

must determine whether the regulatory

action is ‘‘significant’’ and therefore

subject to all the requirements of the

Executive Order (i.e., Regulatory Impact

Analysis and review by the Office of

Management and Budget). Under

section 3(f), the order defines

‘‘significant’’ as those actions likely to

lead to a rule: (1) Having an annual

effect on the economy of $100 million

or more, or adversely and materially

affecting a sector of the economy,

productivity, competition, jobs, the

environment, public health or safety, or

State, local, or tribal governments or

communities (also known as

‘‘economically significant’’); (2) creating

serious inconsistency or otherwise

interfering with an action taken or

planned by another agency; (3)

materially altering the budgetary

impacts of entitlements, grants, user

fees, or loan programs; or (4) raising

novel legal or policy issues arising out

of legal mandates, the President’s

priorities, or the principles set forth in

this order. Pursuant to the terms of this

order, EPA has determined that this

interim final rule would not be

‘‘significant’’.

3. Presidential Review of the Code of

Federal Regulations

On February 22, 1995, President

Clinton announced a review of the Code

of Federal Regulations by all Federal

agencies. The objective of the review is

to: eliminate obsolete regulations,

withdraw outdated or superseded

regulations, propose modifications to

simplify or reduce burden, and to

identify legislation for needed change.

Today’s rule, revising the NTR, is

consistent with the review announced

by the President. EPA has reviewed the

NTR (40 CFR 131.36) and determined

that the use of dissolved metals criteria

in the NTR States, for the metals listed

in this rule, should reduce potential

regulatory burden.

4. Regulatory Flexibility Act

The Regulatory Flexibility Act (5

U.S.C. 601, et seq., Pub. L. 96–354)

requires EPA to assess whether its

regulations create a disproportionate

effect on small entities. EPA discussed

in the NTR rulemaking (December 22,

1992, 57 FR 60909), the potential effects

of the rulemaking on small entities. The

Agency concluded that the rulemaking

would not result in a significant impact

on small entities and a final regulatory

flexibility analysis was not required.

Because the potential impact on small

entities as a result of this interim final

rule revision will be less burdensome on

small entities than the original rule,

EPA, based on the same factors

discussed in the previous final

rulemaking, continues to conclude this

action will not result in a significant

impact on small entities.

5. Paperwork Reduction Act

This interim final rule places no

information collection activities on the

affected States and therefore no

information collection requirement will

be submitted to the Office of

Management and Budget for review in

compliance with the Paperwork

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

List of Subjects in 40 CFR Part 131

Environmental Protection, Water

pollution control, Water quality

standards, Toxic pollutants.

Dated: April 14, 1995.

Carol Browner,

Administrator.

For the reasons set out in the

preamble, title 40, chapter I part 131 of

the Code of Federal Regulations is

amended as follows:

PART 131–WATER QUALITY

STANDARDS

1. The authority citation for part 131

continues to read as follows:

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

2. Section 131.36 is amended by

revising entries 2, 4, 5a,5b,6,7,8,9,10,11,

and 13 of the table at paragraph (b)(1),

revising footnotes ‘‘e’’ and ‘‘l’’ adding

footnotes ‘‘o’’ and ‘‘p’’ to the table in

paragraph (b)(1), removing the ‘‘Note to

paragraph (b)(1)’’, revising paragraph

(b)(2) and by revising the first two

sentences of paragraph (c)(4)(iii) to read

as follows:

§ 131.36 Toxics criteria for those States

not complying with Clean Water Act Section

303(c)(2)(B).

* * * * *
22236 Federal Register / Vol. 60, No. 86 / Thursday, May 4, 1995 / Rules and Regulations

(b)(1) EPA’s Section 304(a) Criteria for Priority Toxic Pollutants.

A B C D

(#) Compound CAS N.

Freshwater Saltwater Human health (10–6 risk

for carcinogens)

Criteria

Maximum

Conc.d (ug/

L) B1

Criteria

Continuous

Conc.d (ug/

L) B2

Criteria

Maximum

Conc.d (ug/

L) C1

Criteria

Continuous

Conc.d (ug/

L) C2

For consumption of:

Water & Organisms

(ug/L) D1

Organisms

only (ug/L)

D2

* * * * * * *

2 Arsenic .................................................... 7440382 m 360 m 190 m 69 m 36 a,b,c0.018

a,b,c

a,b,c 0.14

* * * * * * *

4 Cadmium ................................................. 7440439 e 3.7 e 1.0 m 42 m 9.3 (n) (n)

5a Chromium (III) ....................................... 16065831 e 550 e 180 ................... ................... (n) (n)

b Chromium (VI) ......................................... 18540299 m 15 m 10 m 1100 m 50 (n) (n)

6 Copper ..................................................... 7440508 17 e 11 e m 2.4 m 2.4 ................... ...................

7 Lead ........................................................ 7439921 e 65 e 2.5 m 210 m 8.1 (n) (n)

8 Mercury ................................................... 7439976 m 2.1 i,p 0.012 m 1.8 i,p 0.025 0.14 0.15

9 Nickel ....................................................... 7440020 e 1400 e 160 m 74 m 8.2 a 610 a 4600

10 Selenium ............................................... 7782492 p 20 p 5.0 m 290 m 71 (n) (n)

11 Silver ..................................................... 7440224 e 3.4 m 1.9

* * * * * * *

13 Zinc ........................................................ 7440666 e 110 e 100 m 90 m 81

* * * * * * *

Footnotes:

a. Criteria revised to reflect current agency q1* or RfD, as contained in the Integrated Risk Information System (IRIS). The fish tissue

bioconcentration factor (BCF) from the 1980 criteria documents was retained in all cases.

b. The criteria refers to the inorganic form only.

c. Criteria in the matrix based on carcinogenicity (10¥6 risk). For a risk level of 10¥5, move the decimal point in the matrix value one place to

the right.

d. Criteria Maximum Concentration (CMC) = the highest concentration of a pollutant to which aquatic life can be exposed for a short period of

time (1-hour average) without deleterious effects. Criteria Continuous Concentration (CCC) = the highest concentration of a pollutant to which

aquatic life can be exposed for an extended period of time (4 days) without deleterious effects. ug/L = micrograms per liter

e. Freshwater aquatic life criteria for these metals are expressed as a function of total hardness (mg/L as CaC03), the pollutant’s water effect

ratio (WER) as defined in § 131.36(c) and multiplied by an appropriate dissolved conversion factor as defined in § 131.36(b)(2). For comparative

purposes, the values displayed in this matrix are shown as dissolved metal and correspond to a total hardness of 100 mg/L and a water effect

ratio of 1.0.

* * * * * * *

i. If the CCC for total mercury exceeds 0.012 ug/l more than once in a 3-year period in the ambient water, the edible portion of aquatic species

of concern must be analyzed to determine whether the concentration of methyl mercury exceeds the FDA action level (1.0 mg/kg). If the FDA action level is exceeded, the State must notify the appropriate EPA Regional Administrator, initiate a revision of its mercury criterion in its water

quality standards so as to protect designated uses, and take other appropriate action such as issuance of a fish consumption advisory for the affected area.

* * * * * * *

l. [Reserved: this letter not used as a footnote].

m. Criteria for these metals are expressed as a function of the water effect ratio, WER, as defined in 40 CFR 131.36 (c).

CMC=column B1 or C1 value x WER

CCC=column B2 or C2 value x WER

n. EPA is not promulgating human health criteria for this contaminant. However, permit authorities should address this contaminant in NPDES

permit actions using the State’s existing narrative criteria for toxics.

o. [Reserved: This letter not used as a footnote].

p. Criterion expressed as total recoverable.

* * * * * * *

(2) Factors for Calculating Hardness-Dependent, Freshwater Metals Criteria

CMC=WER exp {mA[ln(hardness)]+bA} x Acute Conversion Factor

CCC=WER exp {mC[ln(hardness)]+bC} x Chronic Conversion Factor

Final CMC and CCC values should be rounded to two significant figures.
Federal Register / Vol. 60, No. 86 / Thursday, May 4, 1995 / Rules and Regulations 22237

Metal mA bA mC bC

Freshwater conversion

factors

Acute Chronic

Cadmium .......................................................................... 1.128 –3.828 0.7852 –3.490 a 0.944 a 0.909

Chromium (III) ................................................................... 0.8190 3.688 0.8190 1.561 0.316 0.860

Copper .............................................................................. 0.9422 –1.464 0.8545 –1.465 0.960 0.960

Lead .................................................................................. 1.273 -1.460 1.273 –4.705 a 0.791 a 0.791

Nickel ................................................................................ 0.8460 3.3612 0.8460 1.1645 0.998 0.997

Silver ................................................................................. 1.72 –6.52 b N/A b N/A 0.85 bN/A

Zinc ................................................................................... 0.8473 0.8604 0.8473 0.7614 0.978 0.986

Note to table: The term ‘‘exp’’ represents the base e exponential function.

Footnotes to table:

aThe freshwater conversion factors (CF) for cadmium and lead are hardness-dependent and can be calculated for any hardness [see limitations in § 131.36(c)(4)] using the following equations:

Cadmium

Acute: CF=1.136672—[(ln hardness)(0.041838)]

Chronic: CF=1.101672—[(ln hardness)(0.041838)]

Lead (Acute and Chronic): CF = 1.46203—[(ln hardness)(0.145712)]

b No chronic criteria are available for silver.

(c) * * *

(4) * * *

(iii) Except where otherwise noted, the criteria for metals (compounds #2, #4–# 11, and #13, in paragraph (b) of

this section) are expressed as dissolved metal. For purposes of calculating aquatic life criteria for metals from the

equations in footnote m. in the criteria matrix in paragraph (b)(1) of this section and the equations in paragraphs

(b)(2) of this section, the water-effect ratio is computed as a specific pollutant’s acute or chronic toxicity values measured

in water from the site covered by the standard, divided by the respective acute or chronic toxicity value in laboratory

dilution water. * * *

* * * * *

[FR Doc. 95–10148 Filed 5–3–95; 8:45 am]

BILLING CODE 6560–50–P