In the matter of Petition for Modification
Island Creek Coal Company
Ohio No. 11 Mine
I.D. No. 15-03178 Docket No. M-97-049-C
PROPOSED DECISION AND ORDER
On April 1, 1997, a petition was filed seeking a modification of the application of 30 CFR 75.364(b)(4) to Petitioner's Ohio No. 11 Mine, located in Union County, Kentucky. The Petitioner alleges that application of this standard will result in a diminution of safety to the miners and that the alternative method proposed in the petition will at all times guarantee no less than the same measure of protection afforded by the standard.
Specifically, the petitioner requests a modification to allow the evaluation of two mine seals which are inaccessible for examination at the seals. Petitioner proposes to conduct weekly evaluations made by a certified person of the air quality and quantity at a down-wind monitoring station for each of the seals and monitoring of water levels above the seals by a float switch alarm system. The seals cannot be safely approached because, in each case, water is impounded in the slopes which originally provided access to a now abandoned mine which worked the lower Kentucky No. 9 coal seam. The impounded water completely covers the petitioned mine seals which were installed in the slopes to isolate the abandoned mine workings. In addition, the water covers nearly all of the roof support systems, roof bolts and lines of roof props/posts originally installed or added as supplemental supports after the slopes were sealed. The petitioner alleges that the presence of impounded water and, even if pumped down, the deterioration of the slope roof support systems make travel to the seals hazardous for mine examiners and that the proposed alternative method of evaluation will provide the same measure of protection as the standard. The petitioner also provides a float switch actuated alarm system which would sound should either of the water pools begin draining into the lower mine workings. The petitioner alleges the monitoring of the water levels by a float will be indicative of any problems with the seals below the impounded water. The float switch alarm system had previously been approved by the District as a ventilation plan provision. That approval had been based upon engineering evaluations which indicated the seal construction in the old supply slope could withstand the weight of the water pooled above it and a commitment that should the float switch alarm activate all electrical power to the belt and in the area would immediately be withdrawn.
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 recommendation, this Proposed Decision and Order (PDO) is issued.
Finding of Fact and Conclusion of Law
Application of 30 CFR 75.364(b)(4) to the subject will result in a diminution of safety to the miners and the special terms and conditions set out below will at all times provide a safe work environment to the miners.
MSHA’s investigation was unable to determine the present condition of the petitioned mine seals or the rock slope approaches to the seals due to the mine pooled water in the slopes. The investigation did not indicate a hazard in approaching the water’s toe of either slope or that the air at those locations contained methane or was oxygen deficient. MSHA believes that conducting examinations at the seals would at a minimum, expose mine examiners to slip and fall hazards when traveling down the wet, slick and inclined entries to take gas checks and visually examine the seals or, if present, the hazards associated with deteriorated ground support systems and/or the hazards of rehabilitating the deterioration of the slope entries.
MSHA also believes that monitoring stations at or near the toe of the water pool in each slope can provide a valid evaluation of the seals. However, since these mine pools have permanent electrical pumping stations and none of the electrical equipment, including the float controlled “alarm system”, is permissible, MSHA has concerns as to whether the proposed reliance on that alarm system warrants only weekly examinations at monitoring stations.
If a seal fails, the water flowing into the abandoned mine could expel potentially methane laden and/or oxygen deficient air across the float actuated alarm system, the pump stations and, into the belt and track entries. The petitioner alleges and MSHA’s investigator concurs that the quantity of air available (entering the mine through the belt slope and supply slope) to dilute any out-gassing of the sealed area is so great that only the electrical equipment in the immediate vicinity of the seals and at the monitoring stations need to be permissible or intrinsically safe electrical equipment. Outby the monitoring stations, the dilution effect and the required responses to an alarm of notifying all the personnel underground and withdrawing power from the area, allows the continued use of non-permissible equipment in the normally intake air belt and haulage entries.
MSHA also understands that the mine has been granted a modification (Docket No. M-90-014-C, finalized granted 7/17/93) allowing the use of belt air to ventilate the working faces but has only implemented the modification on a single working section. The carbon monoxide sensors and “early warning fire detection system” described in the modification have been installed.
The petitioner further alleges that none of the air entering the mine at the supply slope and belt slope ever reaches a working section. All of the air ventilating the belt slope and belt haulage system in this part of the mine is vented to the return. Where the belt-air modification has been or will be implemented air from other intake air slopes/shafts is point fed onto the belt entry near the section mouth. MSHA’s investigator could not confirm these allegations due to the size of the mine and the complexity of the ventilation system. However, the investigator contends that a seal failure/out gassing could result in an ignition or explosion and that any such event would affect the entire mine. As such, any alert or alarm at the monitoring stations must be communicated to all persons underground, evacuation of the underground personnel immediately initiated along safe routes of travel, and the power in the vicinity of the petitioned area immediately withdrawn.
MSHA believes the proposed alternative method requires amending terms and conditions to achieve the same measure of protection afforded by the standard. The atmosphere oxygen and methane contents and water levels need to be continuously monitored at safe locations at or near the toe of the water pools. The sensors and any electrical equipment in the direct path of any atmosphere expelled or drawn from the abandoned mine, should a seal(s) fail, need to be permissible or intrinsically safe electrical equipment. The atmospheric monitoring system should be installed, calibrated and maintained in conformance with the Atmospheric Monitoring System (AMS) requirements of 30 CFR 75.351. The methane or oxygen sensors and water level switch/sensor actuation of an alarm must result in the withdrawal of electric power from the affected area(s) and the immediate evacuation of miners to the surface.
Furthermore, should the belt air modification's Decision and Order be implemented or should the existing pump stations be other than submersible pumps, energized and be in the slope entry, the petitioned area and seals would become required locations for preshift examinations under 30 CFR 75.360 and the proposed modification would no longer be applicable.
On the basis of the petition and the findings of MSHA's investigation, Island Creek Coal Company is granted a modification of the application of 30 CFR 75.364(b)(4) to its Ohio No. 11 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 Island Creek Coal Company’s Petition for Modification of the application of 30 CFR 75.364(b)(4) in the Ohio No. 11 Mine is hereby:
GRANTED, for continuous monitoring using intrinsically safe sensors installed as part of the mines AMS and weekly evaluation for methane and oxygen content of the air ventilating the flooded mine seals No. 1 (Old Supply Slope) and No. 2 (Old belt Slope), conditioned upon compliance with the following terms and conditions:
1. Two monitoring stations that allow evaluation of the return aircourse shall be established at the following locations:
(a) One monitoring station at or near the toe of the water pooled in the Old Supply Slope where air flow would intercept any out-gassing from mine seal No. 1.
(b) One monitoring station at or near the toe of the water pooled in the Old Belt Slope where air flow would intercept any out-gassing from mine seal No. 2.
(c) Each monitoring station shall monitor methane concentration near the roof, oxygen concentration near the floor and water level using a float switch.
The AMS sensors shall be located, to the extent practicable, such that the air flowing over the sensors is representative of the air ventilating the water pooled slope entry after it has mixed with any out-gassing from the inaccessible mine seals and before additional intake air can dilute or reduce methane concentrations or increase oxygen concentrations.
2. A certified person shall:
(a) Examine for hazardous conditions at the monitoring stations. The examination shall be conducted at least every 7 days and include:
(i) examining for hazards on the approaches to and at the monitoring stations;
(ii) visually examining the AMS sensors including the water level float switch;
(iii) testing for methane and oxygen and measuring air velocity and quantity; and,
(iv) determining if the air being continuously monitored is representative of the air ventilating the mine seals and water filled slopes, pump stations and any other electrical equipment immediately down-wind of the inaccessible mine seals.
(b) Determine, from the AMS surface location readouts, the methane concentration, oxygen concentration and the functional status of the water level float switch from the sensors located at the monitoring stations. This determination shall be made daily, within 3 hours preceding the first operating shift, and before anyone on that shift, including certified persons, enters the petitioned area or any underground area ventilated by air that has ventilated the inaccessible mine seals.
(c) Record the results of each weekly examination and each daily determination of the air quality and water level float switch status required by paragraphs 2(a) and (b) in a separate book on the surface which shall be made available to all interested parties. The certification, record keeping, and retention period requirements of 30 CFR 75.364(g), (h), and (i) shall be met.
3. The date, initials of examiner, time, and results of the weekly examinations shall be recorded in a book, or on a date board, that shall be provided at the monitoring stations.
4. An AMS meeting the minimum applicable requirements of 30 CFR 75.351 shall be used to continuously monitor methane, oxygen and the water level float switch. Sensor signals for each of the monitored gases and water level float switch shall activate alarms at the surface location and any affected working sections and any other affected permanent underground locations where miners are scheduled to work or travel. Oxygen, and methane sensors shall be tested and calibrated in accordance with 30 CFR 75.351(f) and the water level float switch tested and calibrated in accordance with the manufacturer's instructions. Manufacturers' information concerning the calibration and accuracy of the sensors and water level float switch used shall be submitted to the District Manager as a part of the mine ventilation plan. The current water level sensor relies on the AMS system monitoring the open or closed status of a float actuated electrical switch. Other types of water level sensors may be used if submitted in advance as a ventilation plan revision and, if suitable, approved by the MSHA District Manager.
5. The AMS monitoring sensors for methane, oxygen and water level shall be capable of providing both visual and audible signals.
(a) A visual or audible alert signal shall be activated at the following levels:
Oxygen 19.9%
Methane 0.5%
Water Level Sensor Malfunction
Float Switch
(b) An audible and visual alarm signal distinguishable from the alert signal shall be activated at the following levels:
Oxygen 19.5%
Methane 1.0%
Water Level Open or Closed
Float Switch Switch Status Change
(c) In lieu of the alert and alarm levels, the District Manager is authorized to require lower alert and alarm levels.
6. The mine evacuation plan required by 30 CFR 75.110123(a) shall be revised to specify the action to be taken to determine the cause of the alert and alarm signals, the location(s) for withdrawal of miners for each alarm signal, the steps to be taken after the cause of an alert signal is determined, and the procedures to be followed if an alarm signal is activated. Such revisions shall be approved by the District Manager. The amount of water level drop required to actuate the water level float switch shall be specified in the mine evacuation plan. Any time the water level falls below the specified depth an alarm signal shall be activated which is indicative of seal failure.
When a methane, oxygen and/or water level sensor gives a visual or audible alert signal, all miners in the affected sections shall be notified immediately and an immediate investigation shall be conducted to determine the cause of the actuation. Action shall be taken to initiate appropriate ventilation changes to reduce the signaling gas concentration or increase air flow quantity or repair or replace the malfunctioning sensor. When a methane, oxygen and/or water level sensor gives an audible and visual alarm signal, all miners on the affected sections and all other locations where miners work or travel inby the mine seals, except those necessary to take corrective actions, shall be withdrawn immediately to the surface until investigation of the event is completed and appropriate ventilation changes have reduced the monitored gas concentration below the alert limits or an effective sealing of the abandoned mine works from the active mine works has been completed.
A record of each alert and alarm signal given and the action taken shall be maintained at the mine for a period of 1 year.
7. Any time the District Manager determines that changes are necessary to ensure the air flowing over a monitoring station is representative of the air flow ventilating the slope entries/mine seals and adequate to ensure that accumulations of methane or oxygen deficient air do not exist, adjustments to the ventilation controls directing air flow into or out of the petitioned area, including removing or adding permanent stoppings or adjustments or moving regulators, shall be made through the mine ventilation plan approval process. If monitoring indicates that minimum air quality standards are not being met or that the water level in the pools has fallen below the specified level and ventilation changes do not restore compliance, then the area shall be sealed immediately.
8. The permanent ventilation controls, monitoring stations and atmospheric monitoring system sensor locations shall be shown on the annual mine ventilation map submitted in accordance with 30 CFR 75.372.
9. All monitoring stations and sensor locations and approaches to these stations and locations shall, at all times be maintained in safe condition. The roof shall be adequately supported by roof bolts or other suitable means to prevent deterioration of the roof in the vicinity of these area.
10. A sign showing the safe travel route to each monitoring station shall be conspicuously displayed in the main intake haulage entry. Such routes shall require approaching the mine seal monitoring station from the fresh air/up-wind air side and the examination shall start at the first up-wind seal/monitoring station.
11. A diagram showing the normal direction and quantity of the air current flow in this area shall be posted at each monitoring station. Such diagram shall be maintained in a legible condition and shall show the cross-sectional area to be used in calculating the air quantities. Any change in the air quantity differing from the previous reading by greater than 5% shall be reported to the mine foreman for immediate investigation.
12. Prior to implementing this alternative method, all mine personnel shall be instructed as to the terms and conditions of this Proposed Decision and Order (PDO). Mine management shall limit travel to the monitoring stations to certified mine examiners, pumpers who are certified mine examiners and personnel assigned to test, repair or maintain equipment at the monitoring stations. All other entry into the old slopes shall be permitted only to investigate and correct problems with air flow detected through the monitoring process and all such work shall be done under the supervision of an authorized person. All persons who work down wind of the petitioned seals shall be instructed in the mine evacuation plan and all provisions of 30 CFR 75.1101-23 and 75.383.
13. Prior to implementing this PDO, an inspection shall be conducted by MSHA to ensure that the terms and conditions of this PDO have been complied with and that the miners have been trained in proper evacuation procedures, including instructions and drills in evacuation.
14. Within 60 days after this PDO becomes final, the Petitioner shall submit proposed revisions for its approved 30 CFR Part 48 training plan to the Coal Mine Safety and Health District Manager. These proposed revisions shall specify initial and refresher training regarding the conditions specified by the PDO.
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, 4015 Wilson Boulevard, Arlington, Virginia 22203.
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.
Robert A. Elam
Deputy Administrator
for Coal Mine Safety and Health