In the matter of: Petition for Modification
Knott County Mining Company
Mine 582
I.D. No. 15-18522 Docket No. M-2003-096-C
PROPOSED DECISION AND ORDER
On December 19, 2003, a petition was filed seeking a modification of the application of 30 CFR 75.900 to Petitioner’s Mine 582 located in Knott County, Kentucky. The Petitioner alleges that the alternative method outlined in the petition will at all times guarantee no less than the same measure of protection afforded by the standard.
MSHA investigators conducted an investigation relevant to the merits of the petition and filed reports of their findings and recommendations with the Administrator for Coal Mine Safety and Health. After a careful review of the entire record, including the petition and MSHA's investigative reports and recommendations, this Proposed Decision and Order is issued.
Finding of Fact and Conclusion of Law
The alternative method proposed by Petitioner (as amended by the recommendations of MSHA) will at all times guarantee no less than the same measure of protection afforded the miners under 30 CFR 75.900.
On the basis of the petition and the findings of MSHA's investigation, Knott County Mining Company is granted a modification of the application of 30 CFR 75.900 to its Mine 582.
ORDER
Wherefore, pursuant to the authority delegated by the Secretary of Labor to the Administrator for Coal Mine Safety and Health, and pursuant to Section 101(c) of the Federal Mine Safety and Health Act of 1977, 30 U.S.C., Sec. 811(c), it is ordered that Knott County Mining Company’s Petition for Modification of the application of 30 CFR 75.900 in the Mine 582, is hereby:
GRANTED, to allow the use of contactors to provide undervoltage and grounded phase and to monitor the grounding conductors for low-voltage power circuits serving the five Horsepower or greater, three-phase alternating current belt drive(s) and pump(s) located in the Mine 582 conditioned upon compliance with the following special terms and conditions:
1. The nominal voltage of the power circuit(s) shall not exceed 480 volts.
2. The nominal voltage of the control circuit shall not exceed 120 volts.
3. The remote close actuator shall be located on the surface, in the belt fire detection monitor room at the main office.
4. A member of management shall initiate a remote close only after a foreman calls to determine it is safe to do so and then only if all the requirements of 30 CFR 75.313 have been satisfied when a main mine fan stoppage has occurred.
5. Vacuum contactors shall be built into or permanently affixed to the transformer enclosure and properly separated and isolated from the other components of the unit.
6. Vacuum contactors with associated protective relays shall provide undervoltage protection for low- and medium-voltage circuits serving three-phase alternating current equipment.
7. The voltage rating of the vacuum contactor(s) shall be at least the maximum RMS voltage of the circuit being protected. The continuous current rating of the vacuum contactor(s) shall be at least 115% of the full load current of the motor(s).
8. A short circuit survey shall be performed by the operator to determine the short circuit current that could occur on the equipment circuits. The contactor will be rated to withstand the short-circuit current to which it would be subjected without compromising the integrity or operation of the unit. The contactor will be required to open only as a control device activated by the ground-monitor circuit and relays, and not in a grounded phase condition.
9. Each circuit breaker installed in conjunction with a contactor shall be equipped with devices to provide short-circuit protection for each piece of equipment. In addition, the design of each installation must ensure coordination of the circuit breaker and vacuum contactor so that the circuit breaker always opens first when a short-circuit occurs.
10. The instantaneous magnetic trip settings of each circuit breaker that provides short circuit protection for the power circuits shall be set in accordance with the requirements of the 2002 National Electric Code.
11. Ground-fault, overload, and short-circuit conditions shall preclude closing the contactor until the molded case breaker is re-closed manually or the overload and ground-fault relays are reset manually.
12. The fail-safe ground check circuit shall cause the contactor to open when either the ground or pilot wire is broken.
13. A monthly exam will be conducted on each circuit to assure proper operation of the vacuum contactor. The monthly exam shall include activating undervoltage, grounded phase, and ground monitor trip devices to test proper operation. The results of the tests of the vacuum contactors shall be recorded with the required monthly tests of the circuit breakers.
14. The pre-start alarm system shall be examined weekly, tested, and properly maintained in accordance with the requirements of 30 CFR 75.512-2. A record showing the results of the examination, test, and maintenance shall be kept at the mine.
15. Prior to each remote start-up, an audible alarm shall be activated for approximately 30 seconds at each affected vacuum contactor or affected area. Circuits shall be wired so that vacuum contactors can only be closed remotely when undervoltage or loss of voltage condition no longer exists. All other conditions that cause the vacuum contactor to trip shall require a manual reset at the vacuum contactor. Circuits providing power to portable or mobile equipment shall not be designed to be remotely reset.
16. The alarm (horns) shall be installed and maintained at each belt drive and section tailpiece. The horns shall be heard over the ambient noise level for a distance of 120 feet in all directions from the area in which it is expected to produce its audible warning. Before starting the belt(s) or pump(s), the alarm shall sound for a minimum of 30 seconds.
17. Pre-start audible alarm units shall operate on a nominal voltage of 24 volts D.C.
18. The Petitioner's alternative method shall not be implemented until MSHA has inspected the installation(s) and determined compliance with all terms and conditions of this petition and applicable 30 CFR requirements.
19. The Petitioner's alternative method shall not be implemented until all qualified persons who perform work on the equipment and circuits have received training in safe maintenance procedures, and the terms and conditions of the Proposed Decision and Order.
20. Within 60 days after this Petition for Modification is granted, the Petitioner shall submit proposed revisions for its approved 30 CFR Part 48 training plan to the Coal Mine Safety and Health District Manager for the area in which the mine is located. These proposed revisions shall specify task training for all miners who are assigned to work in the area. The training shall include the following elements:
a. The purpose of the pre-start alarm systems and vacuum contactor systems;
b. The potential hazards of working on or near belt conveyors and belt conveyor drives; and
c. The requirements of 30 CFR 75.1725(c) and (d).
The procedures of 30 CFR 48.3 for approval of proposed revisions to already approved training plans shall apply.
Any party to this action desiring a hearing on this matter must file in accordance with 30 CFR 44.14, within 30 days. The request for hearing must be filed with the Administrator for Coal Mine Safety and Health, 1100 Wilson Boulevard, Arlington, Virginia 22209-3939.
If a hearing is requested, the request shall contain a concise summary of position on the issues of fact or law desired to be raised by the party requesting the hearing, including specific objections to the proposed decision. A party other than Petitioner who has requested a hearing shall also comment upon all issues of fact or law presented in the petition, and any party to this action requesting a hearing may indicate a desired hearing site. If no request for a hearing is filed within 30 days after service thereof, the Decision and Order will become final and must be posted by the operator on the mine bulletin board at the mine.
John F. Langton
Deputy Administrator
for Coal Mine Safety and Health