Petition for Modification
In the matter of
Oxbow Mining, Inc.
(Formerly Oxbow Carbon and Minerals, Inc.)
Sanborn Creek Mine
I.D. No. 05-04452
Docket No. M-2000-157-C
30 CFR 75.901
PROPOSED DECISION AND ORDER
On November 15, 2000, a petition was filed seeking a modification of the application of 30 CFR 75.901 to Petitioner's Sanborn Creek Mine, located in Gunnison County, Colorado. The Petitioner alleges that the proposed alternative method will at all times guarantee no less than the same measure of protection afforded the miners under 30 CFR 75.901.
MSHA personnel conducted an investigation of the petition and filed a report 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 report and recommendations, this Proposed Decision and Order is issued.
Finding of Fact and Conclusion of Law
The alternative method proposed by the 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 75.901.
On the basis of the petition and the findings of MSHA's investigation, Oxbow Mining, Inc., is granted a modification of the application of 30 CFR 75.901 in the Sanborn Creek Mine.
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 Oxbow Mining, Inc.'s Petition for Modification of the application of 30 CFR 75.901 to the Sanborn Creek Mine is hereby:
GRANTED, for the 480-volt, three-phase, 260KW/325KVA diesel powered generator (DPG) set, Serial No. 31475-1/01, used to supply power to a three-phase wye connected 300 KVA autotransformer and three-phase 480-volt and 995-volt power circuits, conditioned upon compliance with the following terms and conditions:
1. The 260KW, 480-volt, diesel powered generator set with an approved diesel drive engine shall only be used to move equipment in, out and around the mine and to perform minor activities in the mine listed in the body of this petition.
2. The sum of all motors operated from the diesel powered generator system at one time shall not exceed 225 horsepower.
3. The neutral of the wye configured 480-volt generator shall have in series between it and the frame of the generator unit, a 995-volt rated resistor that will limit the fault current to 0.5 ampere continuously.
4. Each 480-volt and 995-volt output circuit that supplies power to equipment shall be equipped with an instantaneous ground-fault relay that will cause its respective circuit breaker(s) to trip when a phase-to-frame fault occurs. The ground-fault protection shall be set at not more than 90 milliamperes.
5. The 480-volt output circuit of the generator that supplies power to the autotransformer shall be equipped with a backup sensitive ground-fault relay that will cause the circuit breaker that supplies power to the transformer to trip and shut down the diesel engine when a phase-to-frame fault occurs. The ground-fault protection shall be set at not more than 90 milliamperes. A time delay may be permitted for coordination with ground-fault protection of the autotransformer output branch circuits. The time delay for the 480-volt circuit breaker that supplies power to the autotransformer to trip shall not exceed 1/4 second from the occurrence of a ground fault.
6. Each three-phase output circuit breaker shall be provided with a means to provide short-circuit, grounded-phase, undervoltage and ground monitoring protection. When connected to a piece of equipment, the instantaneous only trip unit for the circuit breaker in use shall be adjusted to trip at 70 percent of the maximum available short circuit current at the point where the portable cable enters the equipment or the maximum allowable instantaneous settings specified in 30 CFR 75.601-1, whichever is less.
7. When the generator set is used to move equipment or perform work in areas outby the section loading point where equipment is not required to be maintained permissible, the equipment portable cable length(s) shall not exceed the length(s) specified in 30 CFR Part 18, Table 9. This does not limit the use of shorter cables.
8. Permanent label(s) showing the maximum circuit breaker setting(s) and maximum portable cable length(s) shall be installed on each instantaneous trip unit or be maintained near each 480-volt and 995-volt circuit breaker. The permanent label(s) shall be maintained legible.
9. The circuit breakers that supply 480-volt and 995-volt power circuit(s) to the equipment being powered shall be limited to the use of only one circuit breaker at a time when equipment is being moved.
10. When the generator set is used to move equipment or perform work in areas outby the section loading point where equipment is not required to be maintained permissible, the grounding system shall include a MSHA accepted ground wire monitor system, or other no less effective device approved by the District Manager to assure ground continuity between the frame of the generator and the equipment being moved or used.
11. All 995-volt trailing cables extending from the generator to equipment shall be type SHD construction with a minimum rating of 2000 volts. All trailing cables used to supply power to 480-volt equipment shall have a minimum of 2,000-volt rating. All trailing cables shall have an outer jacket that has been accepted by MSHA as flame-resistant.
12. An insulated strain relief device shall be provided on each end of the cable(s) that extends between the generator and the piece of mobile equipment being powered.
13. Prior to moving each piece of equipment or performing work in areas outby the section loading point where the equipment is not required to be maintained permissible, and upon start-up of the diesel generator, a functional test of each ground fault and ground wire monitor system shall be performed by a qualified electrician who meets the requirements of 30 CFR 75.153. A record of each test shall be maintained and made available to authorized representatives of the Secretary and other interested parties.
14. The diesel generator system shall not be operated until after MSHA has initially inspected the equipment and determined that it is in compliance with all the above terms and conditions.
15. The diesel generator system, when in use, shall comply with all other applicable requirements of the Federal Mine Safety and Health Act of 1977 and the applicable requirements of 30 CFR, Part 75.
16. Prior to using the diesel generator system, training shall be conducted for all qualified persons on the proper examination and test procedures to be utilized. The training shall be "hands on" specific, and shall be incorporated into the Part 48 training plan.
17. Within 60 days after this Proposed Decision and Order becomes final, the Petitioner shall submit proposed revisions for its approved 30 CFR Part 48 training plan, at any of the listed mines, to the Coal Mine Safety and Health District Manager. These proposed revisions shall specify the following:
a) The "hands on" specific training specified in Condition No. 16;
b) Initial and annual refresher training regarding the terms and conditions stated in the Proposed Decision and Order; and
c) Training in the hazards of setting short circuit interrupting device(s) too high to adequately protect the 480-volt and 995-volt trailing cables.
The approval procedures as specified in 30 CFR 48.3 for 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, as amended, (Federal Register 53430, December 28, 1990) within 30 days. The request for hearing must be filed with the Administrator for Coal Mine Safety and Health, 4015 Wilson Boulevard, Arlington, Virginia 22203.
If a hearing is requested, the request must contain a concise summary of position on the issues of fact or law desire 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.
_________________________________
Michael J. Lawless
Deputy Administrator
for Coal Mine Safety and Health