E6-3225. Review of National Ambient Air Quality Standards for Lead

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of review.

SUMMARY:

This document describes EPA's plans and schedule for the review of the air quality criteria and national ambient air quality standards (NAAQS) for lead. This review will take into account newly emerging research on the effects of airborne lead on human health and the environment. The schedule for this review incorporates Clean Air Scientific Advisory Committee (CASAC) review and is consistent with the recent decision made by the U.S. District Court, Eastern District of Missouri, Eastern Division that ordered completion of this lead review by September 1, 2008 (Missouri Coalition for the Environment v. EPA, Civil Action No. 4:04-CV-00660 (ERW) (E.D. Mo. Sept. 14, 2005)).

DATES:

The target dates for major milestones in the lead NAAQS review are contained in a chart in SUPPLEMENTARY INFORMATION.

FOR FURTHER INFORMATION CONTACT:

Ms. Ginger Tennant, Office of Air Quality Planning and Standards (C504-06), with regard to review of the standard, or Dr. Lori White, National Center for Environmental Assessment (B243-01), with regard to the air quality criteria document, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711; telephone: [phone] for Ms. Tennant and [phone] for Dr. White; e-mail: [e-mail] and [e-mail].

SUPPLEMENTARY INFORMATION:

Background

On October 5, 1978, the EPA published a final rule setting primary (health-based) and secondary (welfare-based) NAAQS for lead under section 109 of the Clean Air Act (CAA), each set at 1.5 micrograms per cubic meter (μg/m³), maximum arithmetic daily mean averaged over a calendar quarter (43 FR 46258). During the 1980s, EPA conducted an extensive review of the air quality criteria and NAAQS for lead under section 109(d)(1) of the CAA. With full involvement of CASAC and the public, this review led to publication of a revised air quality criteria document (1986), several supplemental documents covering important new studies (1986, 1990), an exposure analysis (1989), and a staff paper (1990). After consideration of these documents, EPA chose not to propose revision of the NAAQS.

On November 9, 2004 (69 FR 64926), EPA formally announced the beginning of the current lead NAAQS review and the start of the development of an updated AQCD by requesting the submission of recent scientific information on specified topics. The release of the first external review draft of the AQCD and the opening of a public comment period for this document was announced on December 2, 2005 (70 FR 72300).

Review Plans and Schedule

The EPA's plan to review the criteria and standards for lead are outlined in the table below, together with target dates for key milestones. As with all NAAQS reviews, the purpose is to update the criteria and to determine whether it is appropriate to retain or revise the standards in light of new scientific and technical information.

The lead NAAQS review, as with other NAAQS reviews, includes a rigorous assessment of relevant scientific information that will be presented in an AQCD prepared by EPA's National Center for Environmental Assessment. The development of the AQCD involves substantial external peer review through public workshops involving the scientific community at large and through iterative reviews of successive drafts by CASAC and the public. The final AQCD will reflect input received through these reviews and will serve to evaluate and integrate this scientific information to ensure that the review of the standards is based on sound science.

The EPA's Office of Air Quality Planning and Standards will also prepare a Staff Paper (SP) for the Administrator, drawing on information in the AQCD. The SP will evaluate the policy implications of the key studies and scientific information contained in the AQCD and identify critical elements that EPA staff believes should be considered in reviewing the standards. The SP is intended to bridge the gap between the scientific review in the AQCD and the public health and welfare policy judgments required of the Administrator in reviewing the lead NAAQS. For that purpose, the SP will present technical analyses including air quality analyses and assessments of human health risks and environmental effects, other factors relevant to the evaluation of the lead NAAQS, as well as staff conclusions and recommendations of options for the Administrator's consideration. The SP will also be reviewed by CASAC and the public, and the final SP will reflect the input received through these reviews.

The court-ordered schedule requires EPA to complete the initial draft of the AQCD no later than December 1, 2005; finalize the AQCD no later than October 1, 2006; prepare an initial draft of the SP no later than January 1, 2007; finalize the SP no later than November 1, 2007; have the proposed rulemaking notice signed no later than May 1, 2008; and have a final rulemaking concerning any revisions to the lead NAAQS signed no later than September 1, 2008. In order to meet this schedule for final rulemaking, EPA has advanced the target dates for some of these milestones. The schedule below represents EPA's best judgment of the target dates necessary for meeting the court-ordered deadlines. Accordingly, EPA intends to adhere closely to this schedule.

Major Milestones in Lead NAAQS Review

Major milestones	Completed/future target date(s)
Call for Information	November 9, 2004.
CASAC Teleconsultation on AQCD Development Plan	March 28, 2005.
Peer Review Workshops for AQCD	August 4-5 and 16-19, 2005.
First Draft AQCD for CASAC and Public Comment	December 1, 2005.
CASAC Meeting on First Draft AQCD	February 28 and March 1, 2006.
Plan for Human Health and Ecological Risk Assessments for CASAC and Public Comment	Late April 2006.
CASAC Consultation on Plan for Human Health and Ecological Risk Assessments	Late May 2006.
Second Draft AQCD for CASAC and Public Comment	Late May 2006.
CASAC Meeting on Second Draft AQCD	July 2006.
Complete Final AQCD	October 1, 2006.
First Draft SP and First Draft Human Health and Ecological Risk Assessment Reports for CASAC and Public Comment	Late November 2006.
CASAC Meeting on First Draft SP and First Draft Human Health and Ecological Risk Assessment Reports	Late January 2007.
Second Draft SP and Second Draft Human Health and Ecological Risk Assessment Reports for CASAC and Public Comment	Mid-June 2007.
CASAC Meeting on Second Draft SP and Second Draft Human Health and Ecological Risk Assessment Reports	Late July 2007.
Complete Final SP and Final Human Health and Ecological Risk Assessment Reports	Late September 2007.
Publish Proposal Notice in Federal Register	Late February 2008.
Final Promulgation Notice Signed by Administrator	September 1, 2008.

List of Subjects in 40 CFR Part 50

• Environmental protection
• Air pollution control
• Carbon monoxide
• Lead
• Nitrogen dioxide
• Ozone
• Particulate matter
• Sulfur oxides

Dated: February 23, 2006.

Jeffrey S. Clark,

Acting Director, Office of Air Quality Planning and Standards.