(a) Samples; procedures; transmittal; notice of excess concentration; periodic reports to Secretary; contents
Each operator of a coal mine shall take accurate samples of the amount of respirable dust in the mine atmosphere to which each miner in the active workings of such mine is exposed. Such samples shall be taken by any device approved by the Secretary and the Secretary of Health and Human Services and in accordance with such methods, at such locations, at such intervals, and in such manner as the Secretaries shall prescribe in the Federal Register within sixty days from December 30, 1969 and from time to time thereafter. Such samples shall be transmitted to the Secretary in a manner established by him, and analyzed and recorded by him in a manner that will assure application of the provisions of section 814(i) of this title when the applicable limit on the concentration of respirable dust required to be maintained under this section is exceeded. The results of such samples shall also be made available to the operator. Each operator shall report and certify to the Secretary at such intervals as the Secretary may require as to the conditions in the active workings of the coal mine, including, but not limited to, the average number of working hours worked during each shift, the quantity and velocity of air regularly reaching the working faces, the method of mining, the amount and pressure of the water, if any, reaching the working faces, and the number, location, and type of sprays, if any, used.

(b) Standards; noncompliance permit; renewal; procedures; limitations; extension period
Except as otherwise provided in this subsection—

(1) Effective on the operative date of this subchapter, each operator shall continuously maintain the average concentration of respirable dust in the mine atmosphere during each shift to which each miner in the active workings of such mine is exposed at or below 3.0 milligrams of respirable dust per cubic meter of air.

(2) Effective three years after December 30, 1969, each operator shall continuously maintain the average concentration of respirable dust in the mine atmosphere during each shift to which each miner in the active workings of such mine is exposed at or below 2.0 milligrams of respirable dust per cubic meter of air.

(3) Any operator who determines that he will be unable, using available technology, to comply with the provisions of paragraph (1) of this subsection, or the provisions of paragraph (2) of this subsection, as appropriate, may file with the Panel, no later than sixty days prior to the effective date of the applicable respirable dust standard established by such paragraphs, an application for a permit for noncompliance. If, in the case of an application for a permit for noncompliance with the 3.0 milligram standard established by paragraph (1) of this subsection, the application satisfies the requirements of subsection (c) of this section, the Panel shall issue a permit for noncompliance to the operator. If, in the case of an application for a permit for noncompliance with the 2.0 milligram standard established by paragraph (2) of this subsection, the application satisfies the requirements of subsection (c) of this section and the Panel determines that the applicant will be unable to comply with such standard, the Panel shall issue to the operator a permit for noncompliance.

(4) In any case in which an operator, who has been issued a permit (including a renewal permit) for noncompliance under this section, determines, not more than ninety days prior to the expiration date of such permit, that he still is unable to comply with the standard established by paragraph (1) of this subsection or the standard established by paragraph (2) of this subsection, as appropriate, he may file with the Panel an application for renewal of the permit. Upon receipt of such application, the Panel, if it determines, after all interested persons have been notified and given an opportunity for a public hearing under section 804 of this title, that the application is in compliance with the provisions of subsection (c) of this section, and that the applicant will be unable to comply with such standard, may renew the permit.

(5) Any such permit or renewal thereof so issued shall be in effect for a period not to exceed one year and shall entitle the permittee during such period to maintain continuously the average concentration of respirable dust in the mine atmosphere during each shift in the working places of such mine to which the permit applies at a level specified by the Panel, which shall be at the lowest level which the application shows the conditions, technology applicable to such mine, and other available and effective control techniques and methods will permit, but in no event shall such level exceed 4.5 milligrams of dust per cubic meter of air during the period when the 3.0 milligram standard is in effect, or 3.0 milligrams of dust per cubic meter of air during the period when the 2.0 milligram standard is in effect.

(6) No permit or renewal thereof for noncompliance shall entitle any operator to an extension of time beyond eighteen months from December 30, 1969 to comply with the 3.0 milligram standard established by paragraph (1) of this subsection, or beyond seventy-two months from December 30, 1969 to comply with the 2.0 milligram standard established by paragraph (2) of this subsection.

(c) Applications for noncompliance; contents
Any application for an initial or renewal permit made pursuant to this section shall contain—

(1) a representation by the applicant and the engineer conducting the survey referred to in paragraph (2) of this subsection that the applicant is unable to comply with the standard applicable under subsection (b)(1) or (b)(2) of this section at specified working places because the technology for reducing the concentration of respirable dust at such places is not available, or because of the lack of other effective control techniques or methods, or because of any combination of such reasons;

(2) an identification of the working places in such mine for which the permit is requested; the results of an engineering survey by a certified engineer of the respirable dust conditions of each working place of the mine with respect to which such application is filed and the ability to reduce such dust to the level required to be maintained in such place under this section; a description of the ventilation system of the mine and its capacity; the quantity and velocity of air regularly reaching the working faces; the method of mining; the amount and pressure of the water, if any, reaching the working faces; the number, location, and type of sprays, if any; action taken to reduce such dust; and such other information as the Panel may require; and

(3) statements by the applicant and the engineer conducting such survey, of the means and methods to be employed to achieve compliance with the applicable standard, the progress made toward achieving compliance, and an estimate of when compliance can be achieved.

(d) Promulgation of new standards; procedures
Beginning six months after the operative date of this subchapter and from time to time thereafter, the Secretary of Health and Human Services shall establish, in accordance with the provisions of section 811 of this title, a schedule reducing the average concentration of respirable dust in the mine atmosphere during each shift to which each miner in the active workings is exposed below the levels established in this section to a level of personal exposure which will prevent new incidences of respiratory disease and the further development of such disease in any person. Such schedule shall specify the minimum time necessary to achieve such levels taking into consideration present and future advancements in technology to reach these levels.

(e) Concentration of respirable dust
References to concentrations of respirable dust in this subchapter mean the average concentration of respirable dust measured with a device approved by the Secretary and the Secretary of Health and Human Services.

(f) Average concentration
For the purpose of this subchapter, the term "average concentration" means a determination which accurately represents the atmospheric conditions with regard to respirable dust to which each miner in the active workings of a mine is exposed (1) as measured, during the 18 month period following December 30, 1969, over a number of continuous production shifts to be determined by the Secretary and the Secretary of Health and Human Services, and (2) as measured thereafter, over a single shift only, unless the Secretary and the Secretary of Health and Human Services find, in accordance with the provisions of section 811 of this title, that such single shift measurement will not, after applying valid statistical techniques to such measurement, accurately represent such atmospheric conditions during such shift.

(g) Compliance inspections
The Secretary shall cause to be made such frequent spot inspections as he deems appropriate of the active workings of coal mines for the purpose of obtaining compliance with the provisions of this subchapter.

(h) Maintenance of respiratory equipment; substitutes for environmental controls
Respiratory equipment approved by the Secretary and the Secretary of Health and Human Services shall be made available to all persons whenever exposed to concentrations of respirable dust in excess of the levels required to be maintained under this chapter. Use of respirators shall not be substituted for environmental control measures in the active workings. Each operator shall maintain a supply of respiratory equipment adequate to deal with occurrences of concentrations of respirable dust in the mine atmosphere in excess of the levels required to be maintained under this chapter.