_GENERAL DOCUMENTS - C1981017 ‎(142)‎

• Permit No: C1981017
• IBM Index Class Name: GENERAL DOCUMENTS
• Doc Name: Bid Documents ‎(IMP)‎
• Permit Index Doc Type: General Correspondence
• Media Type: D
• Archive: No

A zone pressure in the coal can only be relieved
by destroying the structure of that coal , by causing it to
fail before it fails of its own accord. That is a frequent
requirement in the Coal Basin mines, and it dictates the
rate and timing of mining. It is important to understand
that stress zones , where heavy stress threatens bumps ,
bounces and outbursts , are dynamic. Further, unrelieved
stresses compound, tending to cause even greater damage
and danger if later relieved in uncontrolled outbursting and
heaving.
Underground work for stress relief is conducted in
accordance with the Federal Mine Safety and Health Act of
1977 , P.L. 95-164 , and the regulatory requirements of the
Mine Safety and Health Administration.
The federal act says that, concerning unsafe or
hazardous conditions :
(2) (e) The operators of such mines with the
assistance of the miners have the primary responsibility
to prevent the existence of such conditions and
practices in such mines.
Mid-Continent' s roof control plan, approved by the
Mine Safety and Health Administration, Section 8 , Code of
Practice for Outburst Control requires :
8. 0 Code of Practice for Outburst Control
8. 1 Workings which are prone to outburse will
be mined in accordance with the designated mining system
designed to control outbursts, thus providing maximum
protection to the miners.
Outbursting and uncontrolled stress relief must be
prevented as a function of meeting MSHA standards for methane
control :
75. 308 Methane accumulations in face areas.
75. 309 Return air; tests and adjustments .
75. 316-2 Criteria for approval of ventilation
system and methane and dust control plan.
(d) Methane content of return aircourse.
Immediate cleanup of any loose coal is required
under MSHA standards for combustible materials , Subpart E :
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