[Federal Register Volume 65, Number 36 (Wednesday, February 23, 2000)]
[Proposed Rules]
[Pages 8925-8927]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-4243]



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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 152 and 156

[OPP-36190A; FRL-6491-1]

RIN 2070-AC46


Equivalency of Pesticides Metolachlor and S-metolachlor With 
Respect to Ground Water Contamination; Notice of Availability and 
Request for Comment

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of Availability and Request for Comment.

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SUMMARY: The Agency is providing an opportunity for the public and 
affected parties to submit comments on additional information about a 
chemical contained in the proposed Ground Water and Pesticides 
Management Plan (PMP) Rule (61 FR 33260, June 26, 1996). In the 
proposed PMP rule, the Agency proposed, as a condition of continued 
use, that States and Tribes prepare chemical-specific management plans 
for four herbicides that have been shown to persist in the environment 
and leach to ground water, creating a potential unreasonable adverse 
effect on human health and the environment. One of the four pesticides 
in the proposed rule is metolachlor. EPA is seeking additional comment 
on the specific information that is being made available and which is 
described in this document.

DATES: Written comments, identified by the docket number OPP-36190A, 
must be received on or before March 24, 2000.

ADDRESSES: Comments may be submitted by mail, electronically, or in 
person. Please follow the detailed instructions for each method as 
provided in Unit I of the SUPPLEMENTARY INFORMATION section. To ensure 
proper receipt by EPA, it is imperative that you identify docket 
control number OPP-36190A in the subject line on the first page of your 
response.

FOR FURTHER INFORMATION CONTACT: Arthur-Jean B. Williams, Field and 
External Affairs Division (7506C), Office of Pesticide Programs, U.S. 
Environmental Protection Agency, 401 M St., SW., Washington, DC 20460, 
telephone number: 703-305-5239, fax number: 703-308-3259, e-mail 
address: [email protected].

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    This notice of data availability and request for comment is 
directed to the public in general. It may, however, be of particular 
interest to you if you register, distribute, apply, or manage the 
application of a pesticide that contains optically active isomeric 
active ingredients and, in particular, a product enriched for one 
(usually more pesticidally active) optical isomer. In addition, persons 
commenting on the Ground Water and Pesticide Management Plan proposal 
(61 FR 33260, June 26, 1996) (FRL-4981-9) may be particularly 
interested in some or all of these data. Since others may also be 
interested, the Agency has not attempted to describe all the specific 
entities that may be affected by this action. If you have any questions 
regarding the applicability of this action to a particular entity, 
consult the person listed in the ``FOR FURTHER INFORMATION CONTACT.''

B. How Can I Get Additional Information, Including Copies of this 
Document and Other Related Documents?

    1. Electronically. You may obtain copies of this document and 
certain other available support documents from the EPA Internet Home 
Page at http://www.epa.gov/. On the Home Page select ``Laws and 
Regulations'' and then look up the entry for this document under the 
``Federal Register - Environmental Documents.'' You can also go 
directly to the ``Federal Register'' listings at http://www.epa.gov/fedrgstr/.
    2. In person. The Agency has established an official record for 
this action under docket control number OPP-36190A. The official record 
consists of the documents specifically referenced in this action, any 
public comments received during an applicable comment period, and other 
information related to this action, including any information claimed 
as confidential business information (CBI). This official record 
includes the documents that are physically located in the docket, as 
well as the documents that are referenced in those documents. The 
public version of the official record does not include any information 
claimed as CBI. The public version of the official record, which 
includes printed, paper versions of any electronic comments submitted 
during an applicable comment period, is available for inspection in the 
Public Information and Records Integrity Branch (PIRIB), Rm. 119, 
Crystal Mall #2, 1921 Jefferson Davis Highway, Arlington, VA, from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is 703-305-5805.

C. How and to Whom Do I Submit Comments?

    You may submit comments through the mail, in person, or 
electronically. To ensure proper receipt by EPA, it is imperative that 
you identify docket control number OPP-36190A in the subject line on 
the first page of your response.
    1. By mail. Submit your comments to: Public Information and Records 
Integrity Branch (PIRIB), Information Resources and Services Division 
(7502C), Office of Pesticide Programs (OPP), Environmental Protection 
Agency, 401 M St., SW, Washington, DC 20460.
    2. In person or by courier. Deliver your comments to: Public 
Information and Records Integrity Branch (PIRIB), Information Resources 
and Services Division (7502C), Office of Pesticide Programs (OPP), 
Environmental Protection Agency, Rm. 119, Crystal Mall #2, 1921 
Jefferson Davis Highway, Arlington, VA. The PIRIB is open from 8 a.m. 
to 4 p.m., Monday through Friday, excluding legal holidays. The PIRIB 
telephone number is 703-305-5805.
    3. Electronically. You may submit your comments electronically by 
E-mail to: ``[email protected],'' or you can submit a computer disk as 
described above. Do not submit any information electronically that you 
consider to be CBI. Avoid the use of special characters and any form of 
encryption. Electronic submissions will be accepted in Wordperfect 6/7/
8 or ASCII file format. All comments in electronic form must be 
identified by the docket control number OPP-36190A. Electronic comments 
may also be filed online at many Federal Depository Libraries.

D. How Should I Handle CBI That I Want to Submit to the Agency?

    Do not submit any information electronically that you consider to 
be CBI. You may claim information that you submit to EPA in response to 
this document as CBI by marking any part or all of that information as 
CBI. Information so marked will not be disclosed except in accordance 
with procedures set forth in 40 CFR part 2. In addition to one complete 
version of the comment that includes any information claimed as CBI, a 
copy of the comment that does not contain the information claimed as 
CBI must be submitted for inclusion in the public version of the 
official record. Information not marked confidential

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will be included in the public version of the official record without 
prior notice. If you have any questions about CBI or the procedures for 
claiming CBI, please consult the person identified in the FOR FURTHER 
INFORMATION CONTACT.

E. What Should I Consider as I Prepare My Comments for EPA?

    You may find the following suggestions helpful for preparing your 
comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide copies of any technical information and/or data you used 
that support your views.
    4. If you estimate potential burden or costs, explain how you 
arrived at the estimate that you provide.
    5. Provide specific examples to illustrate your concerns.
    6. Offer alternative ways to improve the rule or collection 
activity.
    7. Make sure to submit your comments by the deadline in this 
notice.
    8. To ensure proper receipt by EPA, be sure to identify the docket 
control number assigned to this action in the subject line on the first 
page of your response. You may also provide the name, date, and Federal 
Register citation.

II. Background

    On June 26, 1996, EPA proposed a rule (61 FR 33260) called the 
Ground Water Pesticide Management Plan Rule (``PMP'' or the ``Rule'') 
to protect ground water from the legal, labeled use of certain 
pesticides. When final, this Rule will restrict the legal sale and use 
of four pesticides known to leach to ground water at concentrations 
that may be harmful to human health and the environment. The pesticides 
are alachlor, atrazine, metolachlor, and simazine and are classified as 
either ``probable'' or ``possible'' human carcinogens. In making this 
registration decision, EPA has determined that use of these pesticides 
may cause unreasonable adverse effects on human health and the 
environment in the absence of effective, site-specific management 
measures. These measures are provided by a Ground Water Pesticide 
Management Plan developed by States and Tribes and approved by EPA.

III. Data Available for Comments

A. What Additional Data is EPA Making Available for Comment?

    The Agency is seeking comment on data provided to EPA to support 
the registration of a pesticide formulation enriched with the S-optical 
isomer of metolachlor. The isomer is named CGA 77102 by the registrant, 
and has also been referred to as chiral metolachlor, alpha-metolachlor, 
and S-metolachlor. The enriched formulation also contains R-metolachlor 
(R-optical isomer). Specifically, this notice invites comments on data 
pertaining to the products containing metolachlor, S-metolachlor, and 
R-metolachlor. This notice solicits comments on environmental fate data 
which could be relevant to the question of whether the Agency should 
consider acetamide, 2-chloro--N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-
1-methylethyl)-,(S)- (common name: S-metolachlor), and acetamide, 2-
chloro-N-(2-ethyl-6-methylphenyl)-N-(2- methoxy-1-methylethyl)-,(R)-
(common name: R-metolachlor) to be metolachlor (chemical name: 
acetamide, 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-
methylethyl)-) for purposes of the proposed Ground Water and Pesticides 
Management Plan (PMP) rule. While previous products of metolachlor 
contain equal parts (ratio of 50:50) of the S-metolachlor and R- 
metolachlor (referred to as a racemic mixture of optical isomers or R 
and S enantiomers), more recent formulations contain the S-metolachlor 
and R-metolachlor in a ratio of approximately 88:11. The following 
documents have been placed in the official Docket of the proposed rule 
(OPP-36190A) and are available for your review and comment as described 
in Unit I.B. Please note, the name alpha-metolachlor was used 
extensively in the documents for the formulation enriched with S-
metolachlor and was a common name (now outdated) used by the registrant 
to refer to the same chemical as the S-optical isomer of metolachlor.
    1. Ciba-Geigy letter dated 1/15/96 to EPA Document Processing Desk, 
Attn: Joanne Miler. Application for registration under the Agency 
reduced risk initiative - PR notice 93-9.
    2. Data summary submitted by Ciba-Geigy Corporation, dated 1/11/96 
and 1/12/96 to support the registration of CGA 77102. The reports 
details the magnitude of the residues in corn and soybeans.
    3. Replacement of metolachlor technical with S-metolachlor -- 
review of bridging data, EPA memo dated November 15,1996, from Linda L. 
Kutney, Health Effects Division, to Rich Griffin, Registration 
Division. Reviews bridging data and provides conclusions and 
recommendations.
    4. Ciba-Geigy notice dated 12/19/96 filing for use of existing 
tolerances for metolachlor and addressing the Food Quality Protection 
Act. Cover letter to Joanne Miller, EPA Registration Division, from 
Karen Stumpf, Ciba-Geigy Senior Regulatory Affairs.
    5. EPA memorandum D223753, D223769, D233184 dated 4/11/97 from Dan 
Reider, EPA Environmental Fate and Effects Division, to Joanne Miller, 
EPA Special Review and Reregistration Division. Review of studies for 
CGA 77102, a metolachlor isomer.
    6. Environmental fate data from Ciba-Geigy in support of 
registration of CGA 77102 (DP Barcode D232589, chemical code 10800). 
This package reviews the bridging environmental fate data (soil 
photolysis, mobility, aerobic soil metabolism, unaged leaching, 
adsorption/desorption, and aged soil column leaching) submitted in 
support of registration.
    7. EPA RfD/Peer Review Report of S-metolachlor dated 7/16/97, cover 
memo from George Z. Ghali PhD, EPA Health Effects Division, to Joanne 
Miller, EPA Registration Division. This package reviews toxicological 
data in support of S-metolachlor, including data evaluations records 
(DERS) for developmental toxicity studies in rats and rabbits, 
subchronic toxicity studies in rats and dogs, and a battery of 
mutagenicity studies.

B. Why is EPA Seeking Comment on this Additional Data?

    EPA believes these data show that the fate of metolachlor (the 
50:50 racemic mixture) in the environment is basically the same as the 
fate of CGA-77102 (the enriched S-metolachor mixture containing R-
metolachor with respect to its impact on the environment. This includes 
the major routes of degradation and the propensity to leach to and 
contaminate ground water, and is the reason bridging data were used for 
registering the product enriched with S-metolachlor, containing less R-
metolachlor. Also, limited toxicological investigation was submitted on 
behalf of S-metolachlor in support of the registration as requested by 
the registrant based on the fact that S- metolachor has already been 
subject to extensive toxicological testing during development of 
metolachor. EPA is seeking comment on these points because metolachlor 
and S-metolachor contain the same chemicals and only differ in the 
proportion of R-metolachor and S-metolachor in their mixtures, with the 
CGA 77102 mixture having a

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higher percentage of more biologically active S-metolachor.
    These data also raise the question of whether a pesticide that 
would be subject to the Proposed Ground Water and Pesticide Management 
Plan Rule (including metolachlor) that is reformulated with a different 
proportion of optical isomers should also be subject to the Proposed 
Rule. If the enriched mixture containing the R- and S-enantiomers is 
not subject to the Proposed Rule, then the objective of the Proposed 
Rule, to prevent ground water contamination by the metolachor active 
ingredient, could fail to be achieved. Also, monitoring could not 
determine the effectiveness of the Proposed Rule to prevent 
contamination of metolachlor since water quality testing by the States 
or Tribes could not distinguish between metolachlor with a 50:50 
mixture of optical isomers or an enriched mixture of these isomers.
    Implicit in the decision to consider S-metolachlor as equivalent to 
metolachlor for purposes of the PMP Rule is the acceptance of the 
Health Advisory (HA) for metolachlor as the reference point for S-
metolachlor. This is consistent with the bridging of metolachlor 
toxicity studies to support the registration of S-metolachlor. If, in 
the future, EPA's Office of Drinking Water and Ground Water 
recalculates an HA for S-metolachlor, or establishes a Maximum 
Contaminant Level (MCL) for the chemical, the new value would become 
the new reference point for metolachlor.

IV. Do Any Regulatory Assessment Requirements Apply to this Action?

    No. This action is not a rule, it merely announces the availability 
of and requests comments on additional data and/or information related 
to, among other things, a proposed rule that previously published in 
the Federal Register of June 26, 1996, 61 FR 33260. For information 
about the applicability of the regulatory assessment requirements to 
the proposed rule, please refer to the discussion in Unit VIII of that 
document (61 FR 33293).

List of Subjects

40 CFR Part 152

    Environmental protection, Administrative practice and procedure, 
Pesticides and pest, Reporting and recordkeeping requirements.

40 CFR Part 156

    Environmental protection, Labeling, Occupational safety and health, 
Pesticides and pest, Reporting and recordkeeping requirements.

    Dated: February 16, 2000.
Susan H. Wayland,
Deputy Assistant Administrator Office of Prevention, Pesticides and 
Toxic Substances.
[FR Doc. 00-4243 Filed 2-22-00; 8:45 am]
BILLING CODE 6560-50-F