[Federal Register Volume 65, Number 127 (Friday, June 30, 2000)]
[Proposed Rules]
[Pages 40557-40559]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-16561]


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DEPARTMENT OF LABOR

Mine Safety and Health Administration

30 CFR Parts 57, 72, and 75

RIN 1219-AA74 and 1219-AB11


Diesel Particulate Matter Exposure of Underground Miners

AGENCY: Mine Safety and Health Administration (MSHA), Labor.

ACTION: Proposed rule; availability of documents; request for comments.

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SUMMARY: We (MSHA) are reopening the rulemaking records of our proposed 
rules on diesel particulate matter exposure of underground coal miners 
and underground metal and nonmetal miners. The reopenings are limited 
in scope. Their purpose is to permit public comment on a few recent 
documents that we have added to these records, including some agency 
investigations to verify assertions made by commenters.

DATES: We must receive your comments by July 31, 2000.

ADDRESSES: Send your comments by regular mail or hand deliver them to 
MSHA, Office of Standards, Regulations, and Variances, 4015 Wilson 
Boulevard, Room 631, Arlington, VA 22203-1984. You also may send them 
by telefax (fax) to MSHA, Office of Standards, Regulations, and 
Variances, 703-235-5551; or by electronic mail (e-mail) to 
[email protected]. If you send your

[[Page 40558]]

comments by fax or e-mail, you must clearly identify them as such. We 
encourage you to supplement paper comments with computer files on disk; 
contact us with any questions about format.

FOR FURTHER INFORMATION CONTACT: Carol J. Jones, Director; MSHA Office 
of Standards, Regulations, and Variances; 703-235-1910.

SUPPLEMENTARY INFORMATION: We have developed extensive records 
concerning whether to issue regulations limiting the concentration of 
diesel particulate matter (dpm) in underground coal mines and 
underground metal and nonmetal mines, and what type of rule would be 
appropriate for each sector. We have been working on this initiative 
for a number of years. We issued a proposed rule for underground coal 
mines on April 9, 1998, and a proposed rule for underground metal and 
nonmetal mines on October 29, 1998. Following a period for pre-hearing 
comments on each proposal, we held four public hearings around the 
country on each proposal. After an extension of the comment period for 
each proposal, both records closed on July 26, 1999.
    We have now determined that it is appropriate to add some documents 
to each of these records. You are welcome to comment on the additions 
to both records.

A. Items Being Added to the Metal and Nonmetal Record.

    A key feature of the proposed rule for this sector was the 
establishment of a concentration limit for dpm. Accordingly, in 
reviewing the record, the agency paid particular attention to 
assertions by the mining community that the sampling and analytical 
method which MSHA proposed to use for measuring compliance with that 
limit would not provide accurate results in many cases. Specifically, 
we proposed:

Section 57.5061 Compliance determinations.

    (a) * * *
    (b) The Secretary will collect and analyze samples of diesel 
particulate matter using the method described in NIOSH Analytical 
Method 5040 and determining the amount of total carbon * * *

    In the preamble to the proposed rule (63 FR 58104 et seq.), in 
particular a discussion entitled ``(3) Methods Available to Measure 
DPM'' (63 FR 58127-58130); in Question and Answer #12 (63 FR 58116-
58117); and in the discussion of proposed Sec. 57.5061 (63 FR 58184), 
we reviewed the various approaches used to determine the concentration 
of dpm, and explained our rationale for the approach proposed. 
Moreover, we asserted that the method we proposed to use could 
accurately determine whether dpm emissions in any underground metal or 
nonmetal mine exceeded the proposed concentration limit (with an 
appropriate allowance for a margin of error).
    There was extensive comment on this assertion during the four 
rulemaking hearings and in written pre-hearing and post-hearing 
comments. While some commenters reaffirmed the validity of various 
aspects of the method, a number of commenters asserted that we could 
not rely on this approach for compliance purposes in certain types of 
mines and under various circumstances.
    Specifically, these commenters asserted that some of the material 
being measured as dpm might well be something other than dpm, an 
``interferrent.'' Some asserted that certain types of mineral dust, in 
particular graphite and carbonaceous minerals, were interferrents. 
Other commenters asserted that oil mists from drilling operations and 
cigarette smoking by miners, which can be present in many underground 
metal and nonmetal mines, were interferrents. Some commenters supported 
their claims with study results.
    During the hearings, MSHA representatives expressed concerns about 
the manner in which these studies had been performed and the 
methodology used. When we examined the information provided for the 
record about these studies, our concerns were heightened, thus leaving 
us without enough evidence to verify the existence and scope of the 
alleged interferences.
    We decided that we would attempt to verify the existence and scope 
of the alleged interferrents while we were reviewing other aspects of 
the rulemaking record. Other agencies have followed this approach. The 
situation discussed in Community Nutrition Institute v. Block, 749 F.2d 
50 (D.C. Cir. 1984), Circuit Judges Wilkey, Bork, and Scalia, is an 
example. The case involved studies that Department of Agriculture staff 
conducted in response to comments alleging deficiencies in a 
methodology, and completed after the close of the comment period.
    Accordingly, MSHA's Pittsburgh Safety and Health Technology Center 
conducted five investigations to verify these assertions of 
methodological problems. We have decided to reopen the record to 
provide the mining community an opportunity to review and comment on 
this information. Members of the mining community also requested that 
we reopen the record for this purpose.

B. Items Being Added to the Coal Record

    The rule proposed for this sector would have required certain types 
of underground coal mining equipment to be filtered. We also requested 
comment on an alternative which would have required certain types of 
underground equipment to observe an emissions standard. An emissions 
standard could be achieved using a lower emission engine or filters or 
both. In either case, the efficiency of available filters is one 
important consideration in determining the economic and technological 
feasibility of the rule for coal mines. Thus, during the hearings and 
in the written comments, there was a great deal of discussion on this 
topic, and we compiled an extensive record.
    Some commenters asserted that paper filters could not achieve a 95% 
reduction in emissions from current permissible equipment, as we had 
asserted. Such filters can be directly installed on permissible 
equipment, without the need for additional equipment to cool the 
exhaust (so it will not ignite the filter element). While the record 
does contain considerable evidence on the efficiency of two versions of 
a system known as the DST that first cools the exhaust from 
an engine and then routes it through a paper filter (and in one case a 
catalytic convertor), it contained no definitive information supporting 
the assertion of commenters that a paper filter alone could not achieve 
such efficiencies. Accordingly, in order to verify the assertions of 
commenters, we contracted with Southwest Research Institute to conduct 
an investigation toward this end. We are placing the Institute's report 
of test results in the record and welcome your comments on it.
    The record does contain considerable information on the efficiency 
of hot gas filters (e.g., ceramic monolithic cell, metal sintered, 
fiber wound, etc.), which will play an important role in reducing 
emissions from non-permissible equipment under either regulatory 
scenario described above. This information includes filter efficiency 
tests conducted by VERT (Verminderung der Emissionen von Realmaschinen 
in Tunnelbau), a consortium of several European agencies conducting 
such research in connection with major planned tunneling projects in 
Austria, Switzerland, and Germany. Since the close of the record, these 
VERT tests have continued. We believe it is appropriate to consider the 
full range of their results and are adding their more

[[Page 40559]]

recent test data to the record. We welcome your comments on it.

C. Items Being Added to Both Records

    Since the record closed, several documents have been published 
concerning the risk of dpm. This risk information is applicable to both 
coal's and metal and nonmetal's rulemakings.
    The first item is a report by another Federal authority updating 
information discussed in the record. During the hearings and post-
hearing comments, there was considerable discussion of an October 1998 
report of the Clean Air Scientific Advisory Committee (CASAC) reviewing 
an EPA Diesel Health Assessment Document. This committee has issued a 
new report (``Review of EPA's Health Assessment Document for Diesel 
Emissions'' February 2000) on a revised EPA Diesel Health Assessment 
Document (EPA, Health Assessment Document for Diesel Emissions, Office 
of Research and Development, SAB Review Draft, EPA-600/8-90/057D, 
November 1999). Members of the mining community participated actively 
in the discussions leading to CASAC's newer report. Accordingly, we 
believe it would be appropriate to update our record to reflect any new 
information covered by the revised EPA assessment and the CASAC's 
review of it. Members of the mining community have requested that we 
reopen the record for this purpose.
    The second item is a study by Saverin, R. et al., ``Diesel Exhaust 
and Lung Cancer Mortality in Potash Mining,'' American Journal of 
Industrial Medicine, 36:415-422 (1999). The unpublished version of the 
study was discussed at one of the hearings, and we already have the 
unpublished version of this study in the record. The published version 
which differs slightly from the earlier translation is now available 
and it is normal practice to refer to the published version of a study 
when that version is available. Accordingly, we are adding the 
published version to the record and welcome your comments on it.
    The third item is an epidemiological study investigating the 
association of lung cancer with occupational exposures to diesel 
emissions in Germany. Bruske-Hohlfeld, I. et al., ``Lung Cancer Risk in 
Male Workers Occupationally Exposed to Diesel Motor Emissions in 
Germany,'' American Journal of Industrial Medicine, 36:405-414 (1999). 
The record of this rulemaking includes a lengthy and comprehensive list 
of relevant epidemiological studies. These were discussed in great 
detail by the mining community during the hearings and comment period. 
As a result, we believe it would be inappropriate to leave this recent 
epidemiological study out of the record. Accordingly, we are adding 
this study to the record and welcome your comments on it.
    The fourth item is a study concerning human response to acute dpm 
exposures. Salvi, Sundeep, et al., ``Acute Inflammatory Responses in 
the Airways and Peripheral Blood After Short-Term Exposure to Diesel 
Exhaust in Health Human Volunteers,'' Am. J. Respir. Care Med. 159:702-
709 (1999). Again, the record of this rulemaking includes a 
comprehensive list of relevant studies in this regard, and they were 
discussed by the mining community during the hearings and comment 
period. Since the Agency is opening the record, the addition of this 
recent study is appropriate. Accordingly, this study is being added to 
the record at this time.
    Finally, in its review of the record, the agency noted certain 
comments suggesting that these commenters might not have been aware of 
certain studies that were part of the general scientific literature 
covered by reviews which are included and discussed in the record. 
Accordingly, the agency is placing copies of two such studies directly 
into the record under their own docket numbers, and will accept any 
comments on these studies. [Hou, S.M. et al., ``Relationship between 
hprt mutant frequency, aromatic DNA adducts and genotypes for GSTM1 and 
NAT2 in bus maintenance workers,'' Carcinogenesis, 16:1913-1917 (1995); 
and Ichinose, et al., ``Lung Carcinogenesis and Formation of 8-hydroxy-
deoxyguanosine in Mice by Diesel Exhaust Particles,'' Carcinogenesis, 
18:185-192 (1997).]
    The agency wants to reassure the mining community that since the 
agency's risk assessment covers information relevant to both 
underground coal mines and underground metal and nonmetal mines, any 
comments on the risk assessment filed in one record have also been 
placed in the other. In some cases, commenters placed the comments in 
both records just to be sure MSHA would consider them, but not all did 
so. The agency will follow this same policy with respect to any 
comments on the risk studies which are the subject of this notice.

D. Time for Response

    The Agency is opening the rulemaking record for additional comment 
on only the specific items described above. The agency has determined 
that in light of the limited scope of this reopening, and the extensive 
familiarity of the mining community with the existing record on the 
topics involved, the record will remain open for comments on these 
items for 30 days. The agency does not foresee any extensions will be 
needed. Accordingly, to facilitate comment by the mining community, the 
agency will be pleased to telefax or express mail copies of any of the 
items involved upon request.

    Dated: June 27, 2000.
Robert A. Elam,
Deputy Assistant Secretary for Mine Safety and Health.
[FR Doc. 00-16561 Filed 6-28-00; 8:45 am]
BILLING CODE 4510-43-U