Petition for Modification
In the Matter of
Dally Slate Company and
Slate Belt Industrial Land Development
Docket No. M-1999-004-M
30 CFR §56.19007
Proposed Decision and Order
Background
On May 11, 1999, Dally Slate Company, Dally 2-Pit Diamond-Mill, Doney-Mill Mine (I.D. No. 36-08597) and Slate Belt Industrial Land Development, American Bangor Slate & Stone, Dally Mine (I.D. No. 36-04864) filed a petition for modification of 30 CFR §56.19007. These mines are located in Pen Argyl, Northhampton County, Pennsylvania. The mines are open pit quarries producing dimension slate for various commercial applications. These two mines have a common corporate ownership.
On August 14, 1978, a similar modification was granted at another mine owned by the company, Doney Slate Company, Pit 1, Doney & Diamond Mills (I.D. No 36-00063). The modification was revised on August 4, 1995, and subsequently revoked on February 23, 2000, because the mine was permanently closed.
The relevant standard, 30 CFR §'56.19007, Overtravel and Overspeed Devices provides:
All man hoists shall be provided with devices to prevent overtravel. When utilized in shafts exceeding 100 feet in depth, such hoists shall also be provided with overspeed devices.
The Petitioner has proposed, in lieu of providing a mechanical device to prevent overtravel and overspeed, to use a standby engineer in the event that the operating engineer has a health condition that impairs his or her ability to operate the hoist. Whenever miners are being lowered into or hoisted out of the quarry, the standby engineer would be positioned immediately beside the operating engineer.
The Petitioner has stated the following in support of the petition:
(a) There is no danger of overspeed, due to the speed of the hoist being very slow, less than 100 feet per minute.
(b) Friction bands on the hoist drum and endless drum provide a natural and constant braking power.
(c) A sudden stopping of the engine by a mechanical device, such as a "A dead man's switch," could cause the man box that carries the employees to be suspended in mid-air, thereby creating an increased and unnecessary hazard.
(d) The danger of overtravel is more effectively removed by the presence of a stand-by auxiliary engineer.
(e) A stand-by auxiliary engineer is far more reliable than any mechanical device that is subject to a mechanical breakdown.
The Petitioner alleges that the alternative method would at all times guarantee no less than the same measure of protection afforded by the standard.
The Mine Safety and Health Administration (MSHA) investigators conducted an investigation relevant to the merits of the petition and filed a report of their findings and recommendations with the Administrator for Metal and Nonmetal Mine Safety and Health. After a careful review of the entire record, including the petition and MSHA's investigative report and recommendations, this Proposed Decision and Order is issued.
Findings of Fact and Conclusion of Law
30 CFR §56.19007 requires that man hoists be provided with overtravel and overspeed devices.
MSHA has determined that the danger of overspeed occurs as a result of electrical control system failure or mechanical drive failure. The maximum speed of the hoist rope is 590 feet per minute (fpm). This translates into a vertical hoisting speed of 197 fpm and a horizontal tram speed of 590 fpm. When the overspeed and overtravel protection is installed and adjusted properly, the limit switches activate quickly to effectively stop the conveyance during emergency conditions.
However, due to the unique design and operation of these hoists, controls applicable to aerial tramways (which travel only horizontally) and vertical shafts are not readily adaptable. These hoists are used to transport miners three times a shift. These times include, but are not limited to, the beginning of the shift, the lunch break, and the end of the shift. When used as mantrips, these hoists have operated many years without any accidents.
Therefore, the Administrator finds that the Petitioner has demonstrated that the requested modification will provide an equal or greater level of protection than compliance with the standard, provided the Petitioner complies fully with the conditions set forth in the Order.
Order
Wherefore, pursuant to the authority delegated by the Secretary of Labor to the Administrator, and pursuant to Section 101(c) of the Federal Mine Safety and Health Act of 1977, 30 U.S.C. Section 811(c), it is hereby ordered that a modification of 30 CFR §56.19007 at Dally Slate Company and Slate Belt Industrial Land Development, is hereby:
GRANTED, conditioned upon compliance with the following:
1. A standby hoist operator will be present at all times when personnel are transported. The standby hoist operator will be positioned within reach of the hoist controls, so that immediate action can be taken in the event of an overtravel or overspeed condition. The standby hoist operator will sign the hoist log book along with the regular hoist operator.
2. A signalman will be present at all times when personnel are transported. The signalman will be positioned to be able to observe the conveyance throughout the entire lift and travel hoisting cycle. The signalman will maintain both visual and voice communications (radio or telephone) with the hoist operator at all times during transportation of personnel.
3. Voice communications will be maintained between the conveyance and the hoist operator during transportation of personnel.
4. Voice communications between the quarry work area and the hoist operator will be functional at all times.
If MSHA inspectors find any violations of this Proposed Decision and Order, it will be considered a change in circumstances, which could result in the Administrator taking action to revoke this Modification.
/s/ Earnest C. Teaster, Jr.
Earnest C. Teaster, Jr.
Administrator for
Metal and Nonmetal Mine Safety and Health