33418 Federal Register / Vol. 54, No. 155 / Monday, August 14, 1989 / Rules and Regulations

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 302

[SW H-FRL 3281-8

Reportable Quantity Adjustments

AGENCY: U.S. Environmental Protection

Agency (EPA).

ACTION: Final rule.

SUMMARY: Sections 103(a) and (b) of the

Comprehensive Environmental

Response, Compensation, and Liability

Act of 1980 (CERCLA), as amended,

require that persons in charge of vessels

or facilities from which hazardous

substances have been released in

quantities that are equal to or greater

than their reportable quantities (RQs)

immediately notify the National

Response Center of the release. Section

102(b) sets an RQ of one pound for

hazardous substances, except those

substances for which different RQs have

been established pursuant to section

311(b)(4) of the Clean Water Act (CWA).

In addition to these reporting

requirements section 304 of the

Superfund Amendments and

Reauthorization Act of 1986 (SARA)

Title III requires that releases of

hazardous substances in quantities

equal to or greater than their RQs (or

one pound if a reporting trigger is not

established by regulation) be reported to

State and local authorities.

Section 102(a) of CERCLA authorizes

the U.S. Environmental Protection

Agency (EPA or "the Agency") to adjust

RQs for hazardous substances and to

designate as hazardous substances

those substances that, when released

into the environment, may present

substantial danger to the public health

or welfare or the environment. Currently

there are 725 CERCLA hazardous

substances.' In this rulemaking, EPA is

IEPA proposed RQ adjustments for the

hazardous substances whose RQs are promulgated

In this final rule on March 16, 1987. As of that date,

there were 717 CERCLA hazardous substances.

Changes to the list of CERCLA hazardous

substances since March 16, 1987 are described

below. Four hazardous waste streams (K123, K124,

K125, and K126) were added in a final rule (51 FR

37725) that became effective on April 24, 1987,

bringing the total number of CERCLA hazardous

substances to 721. EPA removed iron dextran and

strontium sulfide from the list In two final rules (53

FR 43878 and 53 FR 43881) effective October 31,

1988, thus reducing the number of CERCLA

hazardous substances to 719. Six hazardous

substances (waste streams K004, K085, K066, K088,

K090, and K091) were added to the CERCLA list in a final rule (53 FR 35412) that became effective on

March 13,1989, increasing the number of CERCLA

promulgating the RQ adjustments for six

of the 273 hazardous substances whose

RQs were proposed to be adjusted in a

March 16, 1987 Notice of Proposed

Rulemaking (NPRM). These six

substances are: 1,4-dioxane, 2-

ethoxyethanol, ethylene oxide, 2-

nitropropane, perchloroethylene, and

saccharin. By making the adjustments

contained in this rulemaking, the

Agency will be able to focus its

resources on those releases which are

most likely to pose potential threats to

public health or welfare or the

environment. In addition, by making

these adjustments, EPA will relieve the

regulated community of the burden of

reporting releases which are unlikely to

pose such threats.

EFFECTIVE DATE: August 14, 1989.

ADDRESSES: The toll-free telephone

number of the National Response Center

is 1-800/424-8802; in the Washington,

DC metropolitan area the number is 1-

202/267-2675.

Docket: Copies of materials relevant

to this rulemaking are contained in

Room M2427 at the U.S. Environmental

Protection Agency, 401 M Street, SW,

Washington, DC 20460 (Docket Number

102 RQ-273C). The docket is available

for inspection between the hours of 9:00

a.m. and 4:00 p.m. Monday through

Friday, excluding Federal holidays. To

review docket materials, you may make

an appointment by calling 1-202/382-

3046. The public may copy a maximum

of 50 pages from any regulatory docket

at no cost. Additional copies cost $.20

per page.

FOR FURTHER INFORMATION CONTACT.

Ivette 0. Vega, Response Standards and

Criteria Branch, Emergency Response

Division, U.S. Environmental Protection

Agency (OS-210), 401 M Street, SW,

Washington, DC 20460, or the RCRA/

Superfund Hotline at 1-800/424-9346; in

the Washington, DC metropolitan area

at 1-202/382-3000.

SUPPLEMENTARY INFORMATION: The

contents of today's preamble are listed

in the following outline:

I. Introduction

A. Statutory Authority

B. Background of this Rulemaking

II. Reportable Quantity Adjustments

A. Introduction

hazardous substances to 725, which Is the current

total. Lastly, based on a final rule published

elsewhere in today's Federal Register. ammonium

thiosulfate will be removed from the CERCLA list 60

days from today's date, thus reducing the number of

CERCLA hazardous substances to 724.

B. Reportable Quantity Adjustment

Methodology -

1. Summary of the Methodology

2. Responses to Comments Received on

the Methodology a. Carcinogen Hazard Ranking

Methodology and the 100-Pound

Maximum RQ

b. Use of NTP and IARC Determinations

c. Application of EPA's Carcinogen

Assessment Guidelines

C. Substances for Which RQs Are

Adjusted

1. Summary

2. Response to Comments

III. Summary of Supporting Analyses

A. Executive Order No. 12291

B. Regulatory Flexibility Act

C. Paperwork Reduction Act

List of Subjects

I. Introduction

A. Statutory Authority

Section 102(b) of the Comprehensive

Environmental Response,

Compensation, and Liability Act of 1980

(CERCLA) (Pub. L. 96-510), 42 U.S.C.

9601 et seq., as amended by the

Superfund Amendments and

Reauthorization Act of 1986 (SARA)

(Pub. L. 99-499), establishes reportable

quantities (RQs) of one pound for

releases of hazardous substances,

except for hazardous substances whose

RQs were established at a different

level pursuant to section 311 of the

CWA. Section 102(a) of CERCLA

authorizes EPA to adjust all of these

RQs by regulation.

Sections 103(a) and (b) of CERCLA

require that the person in charge of a

vessel or facility notify the National

Response Center immediately when

there is a release of a hazardous

substance in an amount equal to or

greater than the RQ for that substance.

This notification requirement serves as

a trigger for informing the government of

a release so that Federal personnel can

evaluate the need for a Federal removal

or remedial action and undertake any

necessary action in a timely fashion.

Under section 104 of CERCLA, the

Federal government may respond

whenever there is a release or

substantial threat of a release of a

hazardous substance into the

environment. Responses are to be taken,

to the extent practicable, in accordance

with the National Oil and Hazardous

Substances Pollution Contingency Plan

(40 CFR Part 300),.which was originally

developed under the CWA and which

has been revised to reflect the

responsibilities and authority created by

CERCLA.
Federal Register / Vol. 54, No. 155 / Monday, August 14, 1989 / Rules and Regulations

If a release meets certain statutory

criteria set out in CERCLA section

103(f)(2), the release may be subject to

more limited reporting requirements.

Specifically, a release is subject to these

limited requirements if the release: (1) Is

continuous and stable in quantity and

rate, and is from a facility for which

notification has been given under

CERCLA section 103(c), or (2) is a

release for which notification has been

given under CERCLA sections 103(a)

and (b) for a period sufficient to

establish continuity, quantity, and

regularity of the release. Notification

must still be givent annually and when

there is a statistically significant

increase in the release. In addition,

CERCLA section 103 provides a

reporting exemption for federally

permitted releases. The definition of

federally permitted release in CERCLA

section 101(10) specifically identifies

releases permitted under certain other

Federal or State programs. Several

commenters claimed that their particular

releases are subject to continuous and/

or federally permitted release treatment.

EPA published proposed regulations to

clarify the reduced reporting

requirement for continuous releases on

April 19, 1988 (53 FR 12868). EPA also

clarified the reporting exemption for

federally permitted releases in proposed

regulations published on July 19, 1988

(53 FR 27268). Comments on continuous

and federally permitted release Issues

submitted in response to the March 16,

1987 NPRM will be addressed in the

upcoming final rules for continuous and

federally permitted releases.

In addition to the reporting

requirements established by CERCLA,

section 304 of SARA Title III requires

the owners and operators of certain

facilities to report releases of CERCLA

hazardous substances to State and local

authorities. SARA Title III section 304

notification must be given immediately

after the release of an RQ or more (one

pound or more if a reporting trigger is

not established by regulation) to the

community emergency coordinator for

each local emergency planning

committee for any area likely to be

affected by the release, and to the State

emergency response commission of any

State likely to be affected by the release.

These notification requirements apply

only to releases that have potential for

off-site exposure and that are from

facilities at which a "hazardous

chemical" (defined by regulations under

the Occupational Safety and Health Act

of 1970 (29 CFR 1910.1200(c)) and section

311 of SARA Title I1) is produced, used,

or stored.

Section 109 of CERCLA and section

325 of SARA Title III authorize EPA to

assess civil penalties for failure to report

releases of hazardous substances that

equal or exceed their RQs. Section 103

of CERCLA, as amended, authorizes

EPA to seek criminal penalties for

submitting false or misleading

information in a notification made

pursuant to CERCLA section 103, and

increases the maximum penalties and

years of imprisonment for violation of

the CERCLA section 103 reporting

requirement.

B. Background of This Rulemaking

On May 25, 1983, EPA proposed a rule

(48 FR 23552) to clarify procedures for

reporting releases of CERCIA

hazardous substances and to adjust RQs

for 387 of the then 696 hazardous

substances. 2 In the May 25, 1983 Notice

of Proposed Rulemaking (NPRM) EPA

also compiled for the first time the list of

"hazardous substances" defined under

section 101(14) of CERCLA. In the

preamble to that NPRM, EPA discussed

in detail the CERCLA notification

provisions, the methodology and criteria

used to adjust the RQ levels, and the RQ

adjustments proposed under section 102

of CERCL4. and under section 311 of the

CWA. EPA promulgated final RQ

adjustments for 340 hazardous

substances in an April 4, 1985 final rule

(50 FR 13456) and for an additional 102

substances in a September 29, 1986 final

rule (51 FR 34534). In an NPRM

published on March 16, 1987 (52 FR

8140), EPA proposed RQ adjustments for

273 hazardous substances. The March

16, 1987 Federal Register also contained

an NPRM in which EPA proposed RQ

adjustments for radionuclides.3 In

addition, in an NPRM published on

March 2, 1988 (53 FR 6762), EPA

reproposed RQ adjfistments for lead

metal and four lead compounds, and

proposed to delist ammonium

thiosulfate as a CERCLA hazardous

substance.

2 Since the May 25. 1983 NPRM, 31 substances

have been added and two substances have been

deleted from the CERCLA list, bringing the total

number of CERCLA hazardous substances to 725.

The 31 substances added to the list are: waste

stream F024 (49 FR 5308; coke oven emissions (49

FR 36560)- waste streams F020, F021, F022. F023,

F020, F027, and "023 (50 FP 1978): waste streams

Kl11. K112. K113. K114, K115, and K16. o-toluidine

and p-toluidine (50 FR 42936); waste streams (117,

Kila, and K136 (51 FR 5327); 2-ethoxyethanol (51 FR

6537; waste streams K123, 1(124, K125, and K126 (51

FR 37725); and waste streams K064, K065, K066,

(0188, K090, and K091 (53 FR 35412). The two

substances deleted from the list are: iron dextran

(53 FR 43878) and strontium sulfide (53 FR 43881).

8 RQ adjustments for radionuclides were promulgated in a final rule published on May 24,

1989 (54 FR 22524).

This rulemaking finalizes the RQ

adjustments for six of the 273 hazardous

substances whose RQs were proposed

for adjustment in the March 16,1987

NPRM. This rule contains EPA's

responses to all issues raised by the

commenters relating to the RQ

adjustment methodology for potential

carcinogenicity, except those

methodology issues not relevant to the

six RQ adjustments promulgated in this

final rule (for further discussion, see

Section II.B.2 of this preamble). This rule

also contains responses to public

comments received on the specific RQ

adjustments for the hazardous

substances in this rulemaking.

Comments were received on the

proposed RQ adjustments for only three

hazardous substances (1,4-dioxane,

perchloroethylene, and saccharin) of the

six hazardous substances for which RQ

adjustments are promulgated in this

rule.

RQ adjustments for 258 hazardous

substances, including 254 of the 273

hazardous substances whose RQs were

proposed for adjustment in the March

16, 1987 NPRM, are contained in a final

rule published elsewhere in today's

Federal Register. As explained in

Section I1.C.2.i of the preamble to the

other final RQ adjustment rule published

in today's Federal Register, EPA will

address the RQs for the remaining 13

substances of the 273 substances that

were the subject of the March 16, 1987

NPRM in a future action.

Section 306(a) of CERCLA, as

amended by SARA section 202, requires

the U.S. Department of Transportation

(DOT) to list and regulate CERCLA

hazardous substances as hazardous

materials under the Hazardous

Materials Transportation Act. Pursuant

to this requirement, DOT promulgated on November 21, 1986, a final rule (51 FR

42174) providing that, when a hazardous

substance is shipped in a quantity equal

to or greater than its RQ, it must be

identified as such in shipping papers

and by package markings. This rule

became effective on July 1, 1987 (51 FR

46672). The rule requires shippers of

hazardous substances in quantities at or

above their RQs to place the notation

"RQ" and the name of the substance on

shipping papers and package markings.

RQs for many of the hazardous

substances proposed for adjustment in

the March 16, 1987 NPRM (including the

six substances whose adjusted RQs are

being promulgated today) were

proposed to be adjusted upward from

their statutory RQs. The estimated

production volume for the six hazardous

substances whose adjusted RQs are

being promulgated today is 4.6 billion

33419
33420 Federal Register / Vol. 54, No. 155 1 Monday, August 14, 1989 / Rules and Regulations

pounds annually. Because this amount

represents a relatively large proportion

of the total production volume of all 273

hazardous substances proposed for RQ

adjustment in the March 16, 1987 NPRM,

many shippers would be subject to a

regulatory burden that is not justified by

the hazards that these substances pose

to human health and the environment.

Once final RQ adjustments are

promulgated for these six hazardous

substances, shippers of less than the

adjusted RQ of a substance will not be

subject to DOT regulations relating to

shipping papers and package markings.

Accordingly, EPA is expediting the

promulgation of a final rule adjusting

RQs for these substances by making this

rule effective immediately upon

promulgation. Because this rule "grants

or recognizes an exemption or relieves a

restriction" under section 553(d)(1) of

the Administrative Procedure Act

(APA), the APA requirement that final

rules become effective no less than 30

days after publication does not apply.

In finalizing these RQ adjustments,

this rule amends Table 302.4 of 40 CFR

Part 302. Section II of this preamble

discusses the RQ adjustments

promulgated in this rulemaking and the

methodology used in making these

adjustments. Section II also includes

EPA's responses to public comments on

the March 16, 1987 NPRM that are

relevant to the six RQ adjustments made

in this rule and to the RQ adjustment

methodology on which these six

adjustments are based. Section III

provides a summary of the analyses

supporting this rulemaking.

II. Reportable Quantity Adjustments

A. Introduction

In this rulemaking, the Agency adjusts

RQs based upon specific scientific and

technical criteria that relate to the

possibility of harm from the release of a

hazardous substance at certain levels.

The quantity released is but one factor

considered by the government when

assessing the need to respond to such a

release. Other factors, assessed on a

case-by-case basis, includd but are not

limited to: (1) The location of the

release; (2) its proximity to drinking

water supplies or other valuable

resources; and (3) the likelihood of

exposure or injury to nearby

populations. The RQ adjustments made

today will enable the Agency to focus its

resources on those releases that are

most likely to pose potential threats to

public health or welfare or the

environment. These adjustments will

also relieve the regulated community

-and emergency response personnel from

the burden of making and responding to

reports of releases that are unlikely to

pose such threats.

In this final rule, the Agency is

adjusting RQs for 1,4-dioxane, 2-

ethoxyethanol, ethylene oxide, 2-

nitropropane, perchloroethylene, and

saccharin. With the exception of 2-

ethoxyethanol (which was not identified

as a potential carcinogen uhder the

identification methodology discussed in

Section II.B. below), all of these

hazardous substances have been

evaluated for potential carcinogenicity

as well as other primary criteria. The

final RQ adjustments promulgated today

are based on the results of this

evaluation. In the case of 2-

ethoxyethanol, its final RQ adjustment

is based on the primary criterion of

chronic toxicity (see the discussion

below).

B. Reportable Quantity Adjustment

Methodology

1. Summary of the Methodology

The Agency has wide discretion in

adjusting the statutory RQs for

hazardous substances under CERCLA.

Administrative feasibility and

practicality are important

considerations. The Agency's

methodology for adjusting RQs begins

with an evaluation of the intrinsic

physical, chemical, and toxicological

properties of each hazardous substance.

The intrinsic properties examinedcalled "primary criteria"-are aquatic

toxicity, mammalian toxicity (oral,

dermal, and inhalation), ignitability,

reactivity, chronic toxicity,4 and

potential carcinogenicity.

The Agency ranks hazardous

substances for each infrinsic property

(except potential carcinogenicity) on a

five-tier scale, associating a specific

range of values on each scale with a

particular RQ value. 5 This five-tier scale

uses the five RQ levels of one, 10, 100,

1000, and 5000 pounds, originally

established pursuant to CWA section

311 (see 40 CFR 117 and 44 FR 50776).

For hazardous substances evaluated for

potential carcinogenicity, each

substance is assigned a hazard ranking

of "high," "medium," or "low." These

hazard rankings correspond to RQ levels

4 EPA is aware that some chronic effects result

from acute (short-term) exposures and considers

such data in the chronic toxicity evaluations. The

Agency Is further evaluating data on chronic effects

resulting from acute exposures to ensure that such

data receive adequate consideration in the RQ

adjustment process.

5 All of the RQs promulgated In this rulemaking are subject to the Agency's review of the most

recent systemic (i.e,. relating to a particular organ system) toxicity data. These RQs will be revised, if

necessary, in a future rulemaking based on the

results of this review.

of one, 10, and 100 pounds, respectively

(see below). Each hazardous substance

evaluated under the various primary

criteria is assigned several tentative RQ

values based on its particular properties

as data allow. The lowest of the

tentative RQs becomes the "primary

criteria RQ" for that substance. After

the primary criteria RQs are assigned,

substances are further evaluated for

their susceptibility to certain

degradative processes, which are used

as secondary adjustment criteria. These

natural degradative processes are

biodegradation, hydrolysis, and

photolysis (BHP). For further discussion

of BHP, see Section II.B.2.a of the

preamble to the final rule in which EPA

promulgates RQ adjustments for 258

hazardous substances, published

elsewhere in today's Federal Register.

If a hazardous substance,.when

released into the environment, degrades

relatively rapidly to a less hazardous

form by one or more of the BHP

processes,6 its RQ (as determined by the

primary RQ adjustment criteria) is

raised one level. This adjustment is

made because the relative potential for

harm to public health or welfare or the

environment posed by the release of

such a substance is reduced by these

degradative processes. Conversely, if a

hazardous substance -degrades to a more

hazardous product after its release, the

original substance is assigned an RQ

equal to the RQ for the more hazardous

substance, which may be one or more

levels lower than the RQ for the original

substance. The downward adjustment is

appropriate because the hazard posed

by the release of the original substance

is increased as a result of BHP.

To identify those CERCLA hazardous

substances that may be potential

carcinogens, EPA reviewed four sources

of human epidemiologic and/or animal

bioassay data on hazardous substances

that suggest possible carcinogenic effect.

These sources are: (1) The Annual

Reports on Carcinogens of the National

Toxicology Program (NTP), U.S.

Department of Health and Human

Services; (2) the Monographs of the

International Agency for Research on

Cancer (IARC); (3) final Agency

determinations published in the Federal

Register identifying substances as

potential carcinogens; and (4) ongoing

determinations by the Agency's Office

of Health and Environmental

6 The specific thresholds for the application of

BlHP to hazardous substances are discussed in the

Technical Background Document to Support

Rulemaking Pursuant to CERCLA Section 102,

Volume 1. March 1985, available for inspection at

Room M2427, U.S. EPA, 401 M Street, Sw.,

Washington. DC 20460.
Federal Register / Vol. 54, No. 155 / Monday, August 14, 1989 / Rules and Regulations

Assessment that substances may be

potential carcinogens, based on either

published or unpublished data.7 The

Agency compared the list of substances

derived from these four sources with the

list of the CERCLA hazardous

substances to determine which

hazardous substances should be

evaluated for potential carcinogenicity.

Not all of the substances so identified

are subsequently ranked for potential

carcinogenicity. Only those substances

that fall within the Agency's weight-ofevidence Groups A, B, or C discussed

below (i.e., known, probable, or possible

human carcinogens) are ranked and

assigned tentative RQs based on

potential carcinogenicity. The evaluation of hazardous

substances for potential carcinogenicity

initially involves a qualitative

assessment of the available scientific

literature on the substance. The data are

reviewed to determine the degree of

certainty or weight of evidence that a

particular hazardous substance is a

human carcinogen. The substance is

then classified in an overall weight-ofevidence category (A, B, C, D, or E).

A hazardous substance is placed in

Group A (known human carcinogen)

only if "sufficient" evidence from human

epidemiologic studies supports a causal

connection between exposure to the

hazardous substance and cancer. Group

B (probable human carcinogen) is

divided into two subgroups, B1 and B2.

Group B1 includes hazardous

substances for which the weight of

evidence of human carcinogenicity

based on epidemiologic studies is

"limited." Group B2 includes hazardous

substances for which there is "no data,"

"inadequate evidence," or "no

evidence" of human carcinogenicity

from epidemiologic studies, but for - which the weight of evidence of

carcinogenicity based on animal studies

is "sufficient." Group C (possible human

carcinogen) includes hazardous

substances with "limited" evidence of

carcinogenicity in animals and

"inadequate evidence," "no data," or "no evidence" from human

epidemiologic studies. As mentioned in

the March 16, 1987 NPRM (52 FR 8144),

Group D substances (not classifiable for

human carcinogenicity) and Group E

substances (evidence of

noncarcinogenicity for humans) are not

I In addition to this application of unpublished

data to identify potential carcinogens, EPA intends

to use such data for the purpose of ranking potential

carcinogens under the CERCLA RQ methodology.

Currently, the Agency is evaluating unpublished

data received on the weight of evidence and

potency of certain potential carcinogens and will

present the results of this evaluation, along with any

RQ adjustments, in a future rulemnking. ,

considered potential carcinogens for

purposes of this rulemaking. - The evaluation of hazardous

substances for potential carcinogenicity

also involves a quantitative assessment

of the available data to calculate the

relative strength of a hazardous

substance to elicit a carcinogenic

response (i.e., the "potency factor"). 8

This quantitative assessment allows the

Agency to rank potential carcinogens on

a numerical scale by identifying the

most potent substances as the most

hazardous. Group I includes those

hazardous substances with the highest

potencies. Other potential carcinogens

with medium and low potencies are

placed in Groups 2 and 3, respectively.

The final step in the hazard ranking

procedure is to combine the qualitative

weight-of-evidence groups and the

quantitative potency factor groups using

a matrix to yield a relative hazard

ranking for each substance. Thus,

hazard rankings are based on two

factors-weight of evidence and

potency-that the Agency believes are

important in describing carcinogenic

hazards. The following is the matrix

used to assign hazard rankings to

potential carcinogens in today's two

final rules:

HAZARD RANKING

Weight-of- Potency group

evidence

group 1 (highest) 2 3 (lowest)

A ....................... High .............. High .......... Medium.

B ....................... High .............. Medium .... Low.

C ....................... Medium ........ Low ........... Low.

D ....................... No hazard ranking Is made. The

other primary criteria are used

to assign the RQ.

E ....................... No hazard ranking Is made. The

other primary criteria are used

to assign the RO.

The matrix is used to group the potential

carcinogens into "high," "medium," and

"low" hazard categories, and is

arranged so that as the weight of

evidence and the potency decrease, the

hazard ranking also decreases. RQ

levels are then assigned to the hazard

rankings as follows: high-one-pound

RQ; medium-10-pound RQ; and low100-pound RQ.

For a more detailed discussion of the

RQ adjustment methodology based on

the primary criterion of potential ,

carcinogenicity, see the preamble to the

8 For an explanation of how potency factors are

calculated, see the Technical Background Document

to Support Rulemaking Pursuant to CERCLA Section

102, Volume 3, available for inspection at Room

M2427, U.S. EPA, 401 M Street, SW., Washington,

DC 20460.

March 16, 1987 NPRM (52 FR 8140) and

the Technical Background Document to

Support Rulemaking Pursuant to

CERCLA Section 102, Volume 3,

available for inspection at Room M2427,

U.S. EPA, 401 M Street, SW.,

Washington, DC 20460.

EPA stated in the March 16, 1987

NPRM (see 52 FR 8146) that it was

reviewing its position on consideration

of benign tumors and pooling of tumor

sites and types, as set forth in the

Agency's Guidelines for Carcinogen

Risk Assessment. 9 The effect of this

review on RQs for potential carcinogens

is discussed in the preamble to the final

rule published elsewhere in today's

Federal Register in which EPA

promulgates RQ adjustments for 258

hazardous substances.

2. Responses to Comments Received on

the Methodology

The Agency received 35 comment

letters on the March 16, 1987 NPRM (52

FR 8140). Ten of these letters contain

comments that address the RQ

adjustment methodology proposed in

that NPRM for evaluating CERCLA

hazardous substances for potential

carcinogenicity. The comments on the

RQ adjustment methodology are

grouped into five categories: (1)

Carcinogen hazard ranking methodology

and the 100-pound maximum RQ; (2) the

use of NTP and IARC publications in the

Agency's identification methodology; (3)

the Agency's use of its Guidelines for

Carcinogen Risk Assessment to derive

RQs; (4) the application of the secondary

RQ adjustment criteria of BHP to

potential carcinogens; and [5) the

application of the CWA mixture rule to

hazardous waste streams. Because none

of the six hazardous substances that are

the subject of this final rule meets the

criteria for applying BHP and none are

hazardous waste streams, the following

discussion focuses on the first three

comment categories. Comments that fall

within the last two categories are

addressed in a final rule published

elsewhere in today's Federal Register

that promulgates RQ adjustments for 254

of the 273 hazardous substances

proposed for adjustment in the March

16, 1987 NPRM.

0 As discussed in Section II.B.2.c below, the

Guidelines provide that benign tumors should be

considered along with malignant tumors unless

there is evidence that the benign tumors do not have

the potential to progress tc malignancies of the

same histogenic origin. The Agency pools tumor

sites and types when each site or type, viewed.

separately, shows a tumor incidence that is elevated

significantly above the incidence in control animals

(51 FR 33992, September 24, 1986).

33421
33422 Federal Register / Vol. 54, No. 155 / Monday, August 14, 1989 I Rules and Regulations

a. Carcinogen Hazard Ranking

Methodology and the 100-Pound

Maximum RQ. In the March 10, 1987

NPRM (52 FR 8140), EPA proposed RQ

adjustments for potential carcinogens of

one, 10, and 100 pounds. Several

commenters objected to the proposed

100-pound maximum RQ for-potential

carcinogens. The commenters

'recommended that hazardous

substances with no greater than

"inadequate" evidence of cancer in

humans and "limited" evidence of

cancer in animals receive 1000- or 5000-

pound RQs.

EPA disagrees with the commenters

for the reasons discussed below. First,

as stated in the March 16, 1987 NPRM,

although cancer is a unique health effect

with its own special properties, it is also

a type of chronic effect. EPA, therefore,

has determined that reference to the

Agency's chronic toxicity methodology

is appropriate in assigning RQs to

potential carcinogens. Under the chronic

toxicity methodology, each substance is

assigned two rating values, one based

on the dose that causes a particular

effect, and one based on the severity of'

the effect. The dose ratings range from

one to 10, with 10 representing the most

toxic substances. The effect ratings also

range from one to 10, with 10

representing the most severe effect. The

product of the dose and effect ratings for

each substance yields a composite

ranking score between one and 100.

Because cancer is a life-threatening

effect, the effect rating for cancer would

be 10 if cancer were ranked on the

chronic toxicity scale. Therefore, the

composite score for any potential

carcinogen would be at least 10. A

composite score of 10 corresponds to an

RQ of 1000 pounds. Thus, a 5000-pound

RQ for a potential carcinogen would be

inappropriate based on the Agency's

chronic toxicity scale (see 52 FR 8145).

Two commenters stated that this

analogy between chronic toxicity and

potential carcinogenicity is not valid

because chronic toxicants have known

human health effects, whereas the

human health effects of potential

carcinogens are often determined by

speculation based on animal data. EPA

believes that these commenters have

exaggerated the distinction between the.

data for chronic toxicity and the data for

potential carcinogenicity. The human

health effects of both chronic toxicants

and potential carcinogens are based to a

large degree on observation of health

effects in experimental animals.

Therefore, the Agency believes that

reference to its chronic toxicity

methodology in determining the RQ

levels for potential carcinogens is

appropriate.

Second, EPA believes that the special

properties of potential carcinogens are

important in assigning RQ levels to

these substances. These special

properties are: (1) The lack of a

demonstrated threshold level below

which a potential carcinogen presents

no risk of cancer, (2) the cumulative

nature of cancer risks; and (3) the fact

that cancer has a latent period that does

not allow direct observation of

carcinogenic risks from substances

newly released into the environment (52

FR 8145, March 16, 1987).

These three special properties of

potential carcinogens suggest a

conservative approach by the Agency in

assigning RQ levels to these substances.

Where a potential carcinogen does not

have a threshold level of exposure

below which it presents no risk of

cancer, each individual exposure,

regardless of amount, may cause

irreversible health effects. The lack of

demonstrated threshold levels for

potential carcinogens also means that

an individual may develop cancer (an

irreversible health effect) at doses that

cause no other physical effects. The

cumulative nature of cancer risks means

that each additional exposure, at any

dose, further increases the likelihood of

a carcinogenic response. Additionally,

for substances that have a latent period

that does not allow direct observation of

carcinogenic risks, the Agency has

greater reason to be conservative in

assessing the health risks accompanying

exposure at any dose. In particular, the

latent period of cancer, when taken

together with the fact that cancer may

develop from doses too small to cause

other physical effects, means that

individuals may not be aware that they

need to leave release sites at which they

may be exposed to dangerous levels of

potential carcinogens. The Agency,

therefore, has determined that the

special properties of potential

carcinogens justify assigning lower RQs

(i.e., one, 10, and 100 pounds) to

potential carcinogens than the RQs that

are assigned to other hazardous

substances (i.e., one, 10, 100, 1000, and

5000 pounds).

In summary, a 100-pound maximum

RQ for potential carcinogens is retained

because (1) reference to the Agency's

chronic toxicity scale shows that a 5000-

pound RQ would be inappropriate for

any potential carcinogen; and (2) the

Agency believes that the special

properties of potential carcinogens

justify a more conservative approach in

setting RQ levels for these substances

than for other hazardous substances.

Several commenters objected to the

fact that the Agency assigns the same

"low" hazard ranking (and resultant 100-

pound RQ) to weight-of-evidence Group

C, potency Group 3 potential

carcinogens that it assigns to weight-ofevidence Group B2, potency Group 3

potential carcinogens. Thus, the

commenters disagreed with the

proposed 100-pound maximum RQ for

potential carcinogens. The commenters

recommended that hazardous .

substances with no greater than

"inadequate" evidence of cancer in

humans and "limited" evidence of

cancer in animals (i.e., weight-ofevidence Group C) receive 1000- or 5000-

pound RQs.

At this time. EPA has decided to

retain the 100-pound maximum RQ for

potential carcinogens. However, EPA

plans to evaluate the RQ adjustment

methodology for potential carcinogens,

particularly the weight-of-evidence

Group C, potency Group 3 substances. 0

The results of this evaluation will be

addressed in a future Agency action.

Note that this continuing investigation

does not alter today's determination that

these substances be assigned RQs of no

more than 100 pounds.

b. Use of NTP and JARC

Determinations. Several commenters

suggested that the Agency not rely on

NTP and IARC determinations as a

basis for RQ rulemakings and

recommended that EPA independently

evaluate the qualitative evidence of

carcinogenicity for each hazardous

substance. In the March 16, 1987 NPRM

(52 FR 8143), the Agency proposed a

procedure for screening the list of

CERCLA hazardous substances to

identify hazardous substances that

might require assessment for potential

carcinogenicity. The NTP annual reports

and IARC monographs are used only as

an initial screen for substances to be

evaluated for potential carcinogenicity

by the Agency. The conclusions reached

by IARC or NTP on specific chemicals

do not determine directly whether a

hazardous substance is considered a

potential carcinogen for purposes of

establishing RQs. Rather, EPA follows

10 Five individual hazardous substances are in

this category: 5-nitro-o-toluidine saccharin; ptoluidine; 1,1,,2-tetrachloroethane; and 1,1.2-

trichloroethane. EPA is promulgating an RQ

adjustment of 100 pounds for saccharin in this final

rule. RQ adjustments of 100 pounds for the other

four weight-of-evidence Group C. potency Group 3

substances are promulgated in a final rule published

elsewhere in today's Federal Register. In that same. final rule, EPA also promulgates RQ adjustments for

seven waste streams (F0S2, K073, K095, K0M8. K112.

K13, and K114) that contain one or more of the five

weight-of-evidence Group C, potency Group a

substances.
o . Federal Register / Vol. 54, No. 155 / Monday, Augusl 14, 1989 / Ruiles and Regulations

the procedures set out in its Guidelines

for Carcinogen Risk Assessment to

make this determination.

c. Application of EPA's Carcinogen

Assessment Guidelines. EPA's

methodology for adjusting RQs for

potential carcinogens is derived from

the Agency's Guidelines on Carcinogen

Risk Assessment. The comments

addressed in this section are directed

toward the Guidelines' classification of

potential carcinogens. Although the

discussion of these issues below is not

an independent defense of the

Guidelines, the Agency's responses to

public comments in this rulemaking are

fully consistent with EPA's response to

comments received during preparation

of the final Guidelines.

Two commenters objected to the

Agency's lack of distinction between the

B1 and B2 weight-of-evidence Groups

for hazard ranking purposes. These

commenters suggested that weight-ofevidence Groups B1 and B2 be

distinguished by assigning B2 potential

carcinogens hazard rankings one level

higher than the hazard rankings for B1

potential carcinogens.

As discussed in Section II.B.1 above,

the Agency has divided weight-ofevidence Group B into two subgroups,

BI and B2. Where there is limited

evidence of carcinogenicity from

epidemiologic studies, a hazardous

substance usually is placed in Group B1.

Hazardous substances for which there is "sufficient" evidence from animal

studies and "inadequate" evidence or "no data" from human epidemiologic

studies are usually placed in Group B2.

The decision to divide Group B into two

subgroups reflects only the type of

evidence of carcinogenicity, not a

judgment that B2 substances are of

lesser concern than B1 substances.

Furthermore, because it is reasonable to

treat hazardous substances for which

there is sufficient evidence of

carcinogenicity in animals (Group B2) as

if they present a carcinogenic risk to

humans, such substances, along with

other substances for which there is

limited evidence from human

epidemiologic studies (Group 131), are

classified as probable human

carcin gens (Group B). Thus, the Agency

believ s that, for RQ adjustment

purpodes, no distinction in levels of*

concern is warranted between Group Bi

and Group 132 substances.

Two commenters suggested that the

Agency not count benign tumors equally

with malignant tumors when there is no

evidence that the benign tumors are

precursors of malignant tumors or are

life threatening. EPA agrees with the

commenters that benign tumors should

not be treated equally with malignant

tumors if there is no evidence that the

benign tumors will progress to

malignancies of the same histogenic

origin. It is recognized, however, that

benign tumors frequently induce

malignant tumors and that benign

tumors often progress to malignant

tumors (see 51 FR 33992, 33994, citing

Interdisciplinary Panel on

Carcinogenicity, 1984, Science 225:686,

note 4). In such cases, the Agency's

consideration of benign tumor data in

assessing potential carcinogenicity is

appropriate.

Several commenters disagreed with

the Agency's use of body surface area

ratios for deriving human potency

values from animal potency calculations

and recommended the use of bodyweight ratios instead. The commenters

argued that the use of body surface area

as an interspecies scaling factor is

based on data relating to the

noncarcinogenic effects of drugs. The

Agency's use of body surface area to

extrapolate from animals to humans

was discussed in the response to

comments on the Proposed Guidelines

for Carcinogen Risk Assessment. In that

response, the Agency concluded that the

choice of the body surface area scaling

factor could be justified by the data on

effects of drugs in various species, and

that EPA would continue to use this

scaling factor unless data on a specific

agent suggests that a different scaling

factor is justified. Furthermore, because

RQs are based on a relative ranking of

substances, the consistent application of

scaling factors to all substances should

not have a material effect on the relative

rankings.

Two commenters objected to the

Agency's policy of pooling tumors at

different sites. The Agency pools tumor

sites, however, only when each site,

viewed separately, shows a significant

elevated tumor incidence. EPA believes

that pooling of tumor sites is justified in

these limited circumstances because an

agent that induces cancer in two

locations is of greater concern than an

agent that induces cancer in only one

location.

The same two commenters objected to

the Agency's use of effective dose

(which takes into account absorption,

distribution, metabolism, and excretion

of potential carcinogens) to calculate

potency. The commenters argued that

administered dose (the actual

experimental dose) should be used to

estimate relative carcinogenic potency

for purposes of assigning RQs. The

commenters acknowledged that

effective dose is appropriate for

estimating absolute measures of risk.

The commenters failed to demonstrate,

however, that-effective dose is

inappropriate for measuring relative

risk. As a practical matter, for most

hazardous substances (approximately 90

percent), EPA uses administered dose

because the Agency lacks information

necessary to distinguish between

administered dose and effective dose.

Nevertheless, where such information is

available, the Agency prefers to use

effective dose rather than administered

dose, because the former is more

appropriate for measuring relative levels

of risk (e.g., RQ levels). Effective dose is

used to determine carcinogenic potency

only when a substance has undergone

extensive studies that have been subject

to peer review.

One commenter stated that the

Agency proposed to regulate animal

carcinogens in the same manner as

known human carcinogens and that

regulation should focus on exposures to

substances with known human health

effects. This commenter is mistaken in

believing that the RQ adjustment

methodology treats animal and human

carcinogens equally. The hazard ranking

methodology used to establish RQs for

potential carcinogens assigns lower RQs

to known human carcinogens of the

same potency as known animal

carcinogens for which the human

evidence is limited or inadequate.

Moreover, EPA does not believe that its

regulation of potential carcinogens

should be limited to those which have

known human health effects, because

the Agency strongly believes that

animal data are relevant to predict the

potential for a carcinogenic response at

some dose in humans.

One commenter argued that

extrapolation from continuous low-dose

exposure studies to effects of one-time

releases cannot be made. The Agency

acknowledges that estimating the

absolute effect of one-time releases from

experimental data is difficult. However,

the establishment of RQs is not based

on an assessment of absolute effects,

and the Agency believes that the

Guidelines for Carcinogen Risk

Assessment (which were followed in

this rulemaking) provide a reasonable

basis for determining a relative ranking

of potential carcinogens. These

guidelines have been peer reviewed and

revised based on public comments and

therefore provide a reasonable basis for

carcinogenic assessment. Furthermore,

the commenter failed to note certain

implications of the relationship between

one-time releases and one-time

exposures. One-time releases can

contaminate water or soil, resulting in

continuous low-dose exposures over a

period of years. Thus, the Agency's

extrapolation from continuous low-dose

33423
33424 Federal Register / Vol. 54, No. 155 / Monday, August 14, 1989 / Rules and Regulations

exposure studies to effects of one-time

releases is reasonable.

This commenter also noted that there

are significant uncertainties involved in

low-dose extrapolation. EPA agrees and,

therefore, has developed an RQ

methodology that does not use low-dose

extrapolation, The methodology relies

instead on the ED1O, that is, the dose

that causes an increased cancer

incidence of 10 percent. Use of the ED10

is advantageous because it eliminates

the issue of low-dose extrapolation for

RQ adjustment purposes.

The same commenter argued that low

doses of certain heavy metals are

essential to human health, and that low

exposures to suspected carcinogens may

not pose significant incremental risks.

Thus, according to the commenter,

extrapolation over a wide range of

doses may not be appropriate.

EPA agrees with the commenter that

certain substances can have both

beneficial effects at low doses and toxic

effects at high doses. In addition, low

doses can have both beneficial and

toxic effects simultaneously. The

question of whether a particular release

will cause exposed individuals to

experience toxic effects, however, is a

question of risk assessment to be made

by the Federal On-Scene Coordinator

(OSC) based on all available

information pertinent to the particular

release. As stated earlier, the

establishment and adjustment ofRQs is

intended to be a reporting trigger rather

than a risk assessment.

For the reasons discussed above, EPA

has decided at this time that no changes

to the Agency's Guidelines for

Carcinogen Risk Assessment are

necessary. Nevertheless, the Agency

continually reviews the Guidelines; if

new information or procedures become

available, the Agency will consider

whether revisions are warranted.

C. Substances for Which RQs Are

Adjusted

1. Summary

Today's final rule adjusts the RQs for

six of the 273 hazardous substances

whose RQs were proposed to be

adjusted in the March 16, 1987 NPRM.

These six RQ adjustments are shown in

the following table:

H IProposed and Hazardous Statutory final RQ

substance I _ _ adjustment

100

1000

10

10

100

Hazadous Stattory Proposed and Hazadous Stattory final RQ

substance RQ adjustment

Saccharin and salts... 1 100

EPA has promulgated the proposed

RQ adjustments without change for each

of these six substances. For the reasons

discussed in Section I.B. of this

preamble, the Agency has decided to

expedite the promulgation of RQ

adjustments for these six substances.

2. Response to Comments

Public comments on the March 16,

1987 NPRM addressed proposed RQ

adjustments for three of the six

hazardous substances In this

rulemaking: 1,4-dioxane, saccharin, and

perchloroethylene. No comments were

received on the proposed RQ

adjustments for 2-ethoxyethanol,

ethylene oxide, and 2-nitropropane.

Two commenters supported adjusting

the RQ for 1,4-dioxane from the onepound statutory level to 100 pounds.

One commenter supported the proposed

RQ adjustment of 100 pounds for

saccharin because, the commenter

suggested, the new reporting level would

be consistent with public health

concerns in general, and with. the lack of

hazard posed by a potential release of

between one and 100 pounds of

saccharin during transportation. The

Agency agrees that the one-pound

statutory RQ for saccharin does not

appropriately reflect its carcinogenic

potential. Saccharin is a weight-ofevidence Group C, potency Group 3

substance which therefore receives a

low hazard ranking and a 100-pound

RQ.

Three commenters recommended that

perchloroethylene should be classified

as a weight-of-evidence Group C

substance, rather than as a Group B2

substance as proposed in the March 16,

1987 NPRM. The available rat tumor

data and mouse tumor data, when

considered together, support the

Agency's current position that

perchloroethylene should fall into the B2

category based on sufficient animal

evidence of carcinogenicity (see

Addendum to Health Assessment

Document for Tetrachloroethylene

(Perchloroethylene), External Review

Draft, April 2, 1986; NTIS #PB86-

174489). EPA's position on this issue is

consistent with the IARC classification

of perchloroethylene. However, it Is

important to note that EPA's B2

classification for perchloroethylene is

based on a draft carcinogenicity

assessment that has not yet been

finalized. If this classification changes

based on the final assessment, and.the

change warrants' an adjustment of the

RQ for perchloroethylene, the RQ will

be adjusted in a future rulemaking.

Pending the results of the Agency's final

carcinogenicity assessment, the B2

classification and 100-pound RQ

adjustment for perchloroethylene will be

maintained in this final rule.

In a final rule published elsewhere in

today's Federal Register, the Agency

responds to public comments on 254 of

the 273 RQ adjustments proposed in the

March 16, 1987 NPRM. As explained in

Section ILC.2.i of the preamble to that

final rule, EPA will address the RQs for

the remaining 13 substances that were

the subject of the March 16,1987 NPRM

in a future action.

IIL SUMMARY OF SUPPORTING

ANALYSES

A. Executive Order No. 12291

Executive Order (E.O.) 12291 requires

that regulations be classified as major or

nonmajor for purposes of review by the

Office of Management and Budget

(OMB). According to E.O. 12291, major

rules are regulations that are likely to

result in:

(1) An annual effect on the economy

of $100 million or more; or

(2) A major increase in costs or prices

for consumers, individuaL industries,

Federal, State, or local government

agencies, or geographic regions; or

(3) Significant adverse effects on

competition, employment, investment,

productivity, innovation, or on the

ability of United States-based

enterprises to compete with foreignbased enterprises in domestic or export

markets.

An economic analysis performed by

the Agency, available for inspection at

Room M2427, U.S. EPA, 401 M Street,

SW., Washington, DC 20460, shows that

today's final rule is nonmajor, because

the rule will result in estimated net cost

savings of $1.5 million annually. The

annual net cost savings of all RQ

adjustments promulgated or proposed to

date (including those contained in this

final rule) is estimated to be $34.7

million. It should be noted that these net

cost savings reflect only those effects of

the RQ adjustments that are: (1) Readily

quantifiable in dollars; and (2)

associated with the notification

requirements under CERCLA section 103

and SARA section 304 (including the

associated activities of recordkeeping,

notification processing, monitoring, and

response).

This final rule has been submitted to

OMB for review, as required by E.O. No.

12291.

1,4-Dioxane ................

2-Ethoxyethanol........

Ethylene oxide ...........

2-Nitropropane ............

Perchloroethylene._...
Federal Register / Vol. 54, No. 155 / Monday, August 14, 1989 / Rules and Regulations

B. Regulatory Flexibility Act

The Regulatory Flexibility Act of 1980

requires that a Regulatory Flexibility

Analysis be performed for all rules that

are likely to have a "significant impact

on a substantial number of small

entities." To determine whether a

Regulatory Flexibility Analysis was

necessary for today's final rule, a

preliminary analysis was conducted

using a computer model that simulated

the typical operation of a small U.S.

chemical company.

The results of the simulation indicate

that the upper-bound total cost of

compliance-to small firms is negligible.

See the Regulatory Impact Analysis of

Reportable Quantity Adjustments Under

Sections 102 and 103 of the

Comprehensive Environmental

Response, Compensation, and Liability

Act. Volume I, March 1985, available for

inspection at Room M2427, U.S. EPA,

401 M Street, SW., Washington,,DC

20460. Therefore, because today's final

rule is not expected to have a significant

impact on small entities, EPA certifies

that no Regulatory Flexibility Analysis

is necessary.

C. Paperwork Reduction Act

EPA requires an Information Impact

Analysis for all rules that impose a

paperwork burden on the public. This

analysis estimates the burden imposed

on parties outside EPA for activities

such as notification or recordkeeping.

Today's final rule will provide a

decrease in the paperwork burden

imposed on the regulated community for

information collection associated with

fewer releases being reportable.

Because the effect of this final rule on

the paperwork burden is a reduction.

EPA has determined that no further

Information Impact Analysis need be

performed.

The information collection

requirements contained in this rule have

been approved by the OMB under the

provisions of the Paperwork Reduction

Act, 44 U.S.C. Section 3501 et seq., and

have been assigned OMB control

number 2050-0046.

The public reporting burden for this

collection of information is estimated to

vary from 8 to 11 hours per response.

including time for reviewing

instructions, searching existing data

sources, gathering and maintaining the

data needed, and completing and

reviewing the collection of information.

Send comments regarding the burden

estimate or any other aspect of this

collection of information, including

suggestions for reducing this burden, to

Chief. Information Policy Branch, PM223, U.S. Environmental Protection

Agency, 401 M Street. SW., Washington.

DC 20460; and to the Office of

Information and Regulatory Affairs,

Office of Management and Budget,

Washington, DC 20503, marked

"Attention: Desk Officer for EPA."

List of Subjects in 40 CFR Part 302

Air pollution control, Chemicals,

Hazardous materials, Hazardous

materials transportation, Hazardous

substances. Hazardous wastes,

Intergovernmental relations, Natural

resources, Oil pollution, Pesticides and

pests, Reporting and recordkeeping

requirements: Superfund, Waste

treatment and disposal. Water pollution

control, Water supply.

Dated: June 26.1989.

William K. Reilly.

Administrator.

For the reasons set forth in the

preamble, 40 CFR Part 302 is amended

as follows:

PART 302-DESIGNATION,

REPORTABLE QUANTITIES, AND

NOTIFICATION

1. The authority citation for Part 302 is

revised to read as follows:

Authority: 42 U.S.C. 9602; 33 U.S.C. 1321

and 1361.

§ 302.4 [Amended]

2. Section 302.4 is amended by

revising the following entries in Table

302.4 and Appendix A to read as set

forth below. The note preceding Table

302.4 is republished without change.

Note: The numbers under the column

headed "CASRN" are the Chemical Abstracts

Service Registry Numbers for each hazardous

substance. Other names by which each

hazardous substance is identified in other

statutes and their implementing regulations

are provided in the "Regulatory Synonyms"

column. The "Statutory RQ" column lists the

RQs for hazardous substances established by

section 102 of CERCLA. The "Statutory

Code' column indicates the statutory source

for designating each substance. as a CERCLA

hazardous substance: "1" indicates that the

statutory source is section 311(b)(4) of the

Clean Water Act, "2" indicates that the

source is section 307(a) of the Clean Water

Act. "3" indicates that the source is section

112 of the Clean Air Act, and "4" indicates

that the source is RCRA section 3001. The

"RCRA Waste Number". column provides the

waste identification numbers assigned to

various substances by RCRA regulations. The

column headed "Category" lists the code

letters "X," "A," "B," "C," and "D," which are

associated with reportable quantities of 1, 10.

100, 1000, and 5000 pounds, respectively. The

"Pounds (kg" column provides the reportable

quantity adjustment for each hazardous

substance in pounds and kilograms.

TABLE 302.4-LiST OF HAZARDOUS SUBSTANCES AND REPORTABLE QUANTITIES

CAS Statutory Final RO

Hazardous substance CSNRegulatory synonyms RO Codet I waste CRA Cate aor - Pounds (Kg)

r so. ogory 

t.2.Benzisothiazolin-3-one, l.1-dioxide, and salts .....

1 .4-Diethylene dioxide ............ ... .......

1.4-Dioxane ........... ...... ...................................

Ethene, 1.1,2,2-tetrachloro- ........................................

2.Ethoxyethanol ..................................................

Ethylene glycol monoethyl ether .............................

81072 Saccharin and salts .................................................

123911

123911

127184

1,4-Doxane ..................................................................

1 .4-Diethylene dioxide ............... . ..........

Perchloroethylene ........................................................

Tetrachloroethene .........................................................

Tetrachoroethylene ............... .............

110805 Ethylene glycol monoethyl ether . ... ............

110605 2-Ethoxyetlanol .............................................................

U108

U108

U210

U359

U359

100 (45.4)

100 (45.4)

100 (45.4)

100 (45.4)

1000 (454)

1000 (454)

33425
33426 Federal Rigigtdr /' Vol. 54, No.'155 J Monday, August 14, i989 / Rules auid Regulations

TABLE 302.4-LIST OF HAZARDOUS SUBSTANCES AND REPORTABLE QUANTITIES-Continued

Statutory Final RO

Hazardous substance CASRN Regulatory synonyms RCRA CateRO Codet waste Pounds (Kg) No. gory

Ethylene oxide .............. ................ 75218 Oxirane ............................................................................ 1. 4 U115 A 10(4.54)

2-Nitropropane .............................................................. 79469 Propane, 2-nitro- .............. ................... .. 4 U171 A 10 (4.54)

Oxirane ............................................................................ 75218 Ethylene oxide .......................................................... I . 4 Ul15 A 10 (4.54)

Perchloroethylene ......................................................... 127184 Ethene, 1,1,2,2-tetrachloro- .......................................... 1" 2,4 U210 B 100 (45.4)

Tetrachloroethene .......................................................... Tetrachloroethylene ......................................................

Propane, 2-nitro-. ................................................. 79469 2-Nitropropane .......................... 1. 4 U171 A 10 (4.54)

Saccharin and salts ........................ 81072 1,2-Benzisothiazolin-3-one,l,l-dioxide, and salts 1* 4 U202 B 100 (45.4)

Tetrachloroethene .......................................................... 127184 Ethene, 1,1,2,2-tetrachloro-. ......................................... 1 2,4 U210 B 100 (45.4)

Perchloroethylene ..........................................................

Tetrachloroethylene ....................................................... Tetrachloroethylene .......................................... 127184 Ethene, 1,1,2,2-tetrachloro .......................................... 1* 2,4 U210 B 100 (45.4)

Perchloroethylene .......................................................... Tetrachloroethene ................. . ............

t-indicates the statutory source as defined by 1, 2, 3, or 4 below: 1--indicates that the statutory source for designation of this hazardous substance under CERCLA Is CWA Section 311 (b)(4) 2-indicates that the statutory source for designation of this hazardous substance under CERCLA is CWA Section 307(a) 3-Indicates that the statutory source for designation of this hazardous substance under CERCLA is CAA Section 112

4-indicates that the statutory source for designation of this hazardous substance under CERCLA is RCRA Section 3001

1 *-indicates that the 1-pound RQ is a CERCLA statutory RO

Appendix A

SEQUENTIAL CAS REGISTRY NUMBER LIST

OF CERCLA HAZARDOUS SUBSTANCES

CASRN Hazardous substance

75218 . Ethylene oxide

Oxirane

79469 . Propane, 2-nitro2-Nitropropane

81072 ....... 1,2-Benzisothiazolin-3-one,l,l-dioxide,

and salts

Saccharin and salts

110805 . Ethylene glycol monoethy ether

2-Ethoxyethanol

123911 1,4-Diethylene dioxide

1,4-Dioxane

127184 . Ethene, 1,1,2,2-tetrachloroPerchloroethylene

Tetrachloroethene

Tetrachloroethylene

[FR Doc. 89-15745 Filed 8-11-89; 8:45 am]

BILLING CODE S660-50-M

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Parts 116,117, and 302

[SW H-FRL 3372-81

Reportable Quantity Adjustments;

Delisting of Ammonium Thiosulfate

AGENCY: U.S. Environmental Protection

Agency (EPA).

ACTION: Final rule.

SUMMARY: Sections 103(a) and (b) of the

Comprehensive Environmental

Response, Compensation, and Liability

Act of 1980 (CERCLA), as amended,

require that persons in charge Of vessels

or facilities from which hazardous

substances have been released in

quantities that are equal to or greater

than their reportable quantities (RQs)

immediately notify the National

Response Center of the release. Section

102(b) sets an RQ of one pound for

hazardous substances, except those

substances for which different RQs have

been established pursuant to section

311(b)(4) of the Clean Water Act (CWA).

In addition to these reporting

requirements, section 304 of the

Superfund Amendments and

Reauthorization Act of 1986 (SARA)

Title III requires that releases of

hazardous substances in quantities

equal to or greater than their RQs (or

one pound if a reporting trigger is not

established by regulation) be reported to

State and local authorities.

Section 102(a) of CERCLA authoizes

the U.S. Environmental Protection

Agency (EPA or "the Agency") to adjust

RQs for hazardous substances and to

designate as hazardous substances

those substances that, when released

into the environment, may present

substantial danger to the public health

or welfare or the environment.

Currently, there are 725 CERCLA

hazardous substances. 1 In this

rulemaking, EPA is promulgating final

RQ adjustments for 258 hazardous

substances. Of these 258 hazardous

substances, 254 had RQs proposed for

adjustment by EPA in a Notice of

Proposed Rulemaking (NPRM) published

on March 16, 1987 (52 FR 8140). 2 RQs for

four additional hazardous substances

that were not proposed for adjustment

in the March 16, 1987 NPRM are also

included in this final rule. These four

hazardous substances are waste

streams that were listed as hazardous

under section 3001 of the Resource

Conservation and Recovery Act (RCRA)

'See Note I at the end of the text of this

preamble.

2 See Note 2 at the end of the text of this

preamble.