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[April 24, 2006 (Volume 71, Number 78)]
[Unified Agenda]
[Page 22922-22923]

Department of Labor (DOL)
Mine Safety and Health Administration (MSHA)
Final Rule Stage



Priority: Other Significant

Legal Authority: 30 USC 811; 30 USC 813

CFR Citation: 30 CFR 57

Legal Deadline: None

Abstract: On January 19, 2001 MSHA published a final rule addressing diesel particulate matter (DPM) exposure of underground metal and nonmetal miners (66 FR 5706). The final rule established new health standards for underground metal and nonmetal mines that use equipment powered by diesel engines. The rule established an interim concentration limit of 400 micrograms of total carbon per cubic meter of air that became applicable July 20, 2002, and a final concentration limit of 160 micrograms to become applicable after January 19, 2006. Industry challenged the rule and organized labor intervened in the litigation. Settlement negotiations with the litigants have resulted in further regulatory actions on several requirements of the rule. One final rule was published on February 27, 2002,(67 FR 9180). MSHA issued an advance notice of proposed rulemaking (ANPRM) on September 25, 2002, (67 FR 60199) to obtain additional information and published a notice of proposed rulemaking (NPRM) in August 2003 (68 FR 48668). MSHA issued a final rule on June 6, 2005(70 FR 32868) that revises MSHA's existing standards addressing diesel particulate matter (DPM) exposure in underground metal and nonmetal(M/NM) mines. The rule, among other things, changes the interim concentration limit measured by total carbon(TC) to a comparable permissible exposure limit(PEL)measured by elemental carbon(EC). MSHA is developing a rule to phase in implementation of the final limit. On September 7, 2005, MSHA proposed a rule to phase in the final DPM limit because the agency was concerned that there may be feasibility issues for some mines to meet the final limit of 160 micrograms by January 20, 2006. Accordingly, MSHA proposed a five-year phase-in period and noted our intent to initiate a separate rulemaking to convert the final DPM limit from a total carbon limit to an elemental carbon limit. We also proposed to delete the existing provision that restricts newer mines from applying for an extension of time for meeting the final concentration limit. In addition, we requested comments and data on an appropriate conversion factor for the final DPM limit, technological implementation issues, and the costs and benefits of the proposed rule. We also requested comments on the appropriateness of including in a final rule a provision for medical evaluation of miners required to wear respiratory protection and transfer of miners who have been determined by a medical professional to be unable to wear a respirator. Public hearings were held in January 2006.

Statement of Need: As a result of the first partial settlement with the litigants, MSHA published two documents in the Federal Register on July 5, 2001. One document delayed the effective date of 57.5066(b) regarding the tagging provisions of the maintenance standard; clarified the effective dates of certain provisions of the final rule; and gave correction amendments (66 FR 35518).

The second document was a proposed rule to clarify 57.5066(b)(1) and (b)(2) of the maintenance standards and to add a new paragraph (b)(3) to 57.5067 regarding the transfer of existing diesel equipment from one underground mine to another underground mine (66 FR 35521). The final rule on these issues was published February 27, 2002, and became effective March 29, 2002.

As a result of the second partial settlement agreement, MSHA proposed specific changes to the 2001 DPM final rule. On September 25, 2002, MSHA published an ANPRM. In response to commenters, MSHA proposed and finalized changes only to the interim DPM standard of 400 micrograms per cubic meter of air. MSHA also committed to proposing a rule to revise the final DPM limit of 160 micrograms per cubic meter of air.

Summary of Legal Basis: Promulgation of this regulation is authorized by sections 101 and 103 of the Federal Mine Safety and Health Act of 1977.

Alternatives: This rulemaking would amend and improve health protection from that afforded by the existing standard.

Anticipated Cost and Benefits: MSHA's preliminary economic analysis indicates that making the changes under consideration would result in a net cost savings to the mining industry.

Risks: A number of epidemiological studies have found that exposure to diesel exhaust presents potential health risks to miners. These potential adverse health effects range from headaches and nausea to respiratory disease and cancer. In the confined space of the underground mining environment, occupational exposure to diesel exhaust may present a greater hazard due to ventilation limitations and the presence of other airborne contaminants, such as toxic mine dusts or mine gases. MSHA believe that the health evidence forms a reasonable basis for reducing miners' exposure to diesel particulate matter. Proceeding with rulemaking on the provisions discussed above will more effectively reduce miners' exposure to DPM.


Action                            Date                      FR Cite


Final Action                    02/27/02                     67 FR 9180
ANPRM                           09/25/02                    67 FR 60199
ANPRM Comment Period End        11/25/02
NPRM                            08/14/03                    68 FR 48668
NPRM Comment Period End         10/14/03
Limited Reopening of the Comment 
Period                          02/20/04                     69 FR 7881
Limited Reopening of the Comment 
Period End                      04/05/04                     69 FR 7881
Final Action                    06/06/05                    70 FR 32868
Final Action Effective          07/06/05
Second NPRM                     09/07/05                    70 FR 53280
Notice of Public Hearing        09/07/05                    70 FR 53280
Close of Comment Period         09/07/05                    70 FR 53280
Request for Data                09/07/05                    70 FR 53280
Comment Period Extended         09/19/05                    70 FR 55018
Change of Public Hearings Dates 09/19/05                    70 FR 55018
Extension Of Comment Period     01/26/06                     71 FR 4331
Final Action                    05/00/06

Regulatory Flexibility Analysis Required: Yes

Small Entities Affected: Businesses

Government Levels Affected: None Agency Contact: Patricia W. Silvey, Acting Director, Office of
Standards, Regulations, and Variances, Department of Labor, Mine Safety
and Health Administration, 1100 Wilson Boulevard, Room 2349, Arlington,
VA 22209-3939
Phone: 202 693-9440
Fax: 202 693-9441

RIN: 1219-AB29