Petitions for Modification of Application of Existing Mandatory Safety Standard

AGENCY:

Mine Safety and Health Administration, Labor.

ACTION:

Notice.

SUMMARY:

This notice is a summary of petition for modification submitted to the Mine Safety and Health Administration (MSHA) by the parties listed below.

DATES:

All comments on the petition must be received by MSHA's Office of Standards, Regulations, and Variances on or before May 20, 2019.

ADDRESSES:

You may submit your comments, identified by “docket number” on the subject line, by any of the following methods:

1. Email: zzMSHA-comments@dol.gov. Include the docket number of the petition in the subject line of the message.

2. Facsimile: 202-693-9441.

3. Regular Mail or Hand Delivery: MSHA, Office of Standards, Regulations, and Variances, 201 12th Street South, Suite 4E401, Arlington, Virginia 22202-5452, Attention: Sheila McConnell, Director, Office of Standards, Regulations, and Variances. Persons delivering documents are required to check in at the receptionist's desk in Suite 4E401. Individuals may inspect a copy of the petitions and comments during normal business hours at the address listed above.

MSHA will consider only comments postmarked by the U.S. Postal Service or proof of delivery from another delivery service such as UPS or Federal Express on or before the deadline for comments.

FOR FURTHER INFORMATION CONTACT:

Barbara Barron, Office of Standards, Regulations, and Variances at 202-693-9447 (voice), barron.barbara@dol.gov (email), or 202-693-9441 (fax). [These are not toll-free numbers.]

SUPPLEMENTARY INFORMATION:

Section 101(c) of the Federal Mine Safety and Health Act of 1977 and Title 30 of the Code of Federal Regulations Part 44 govern the application, processing, and disposition of petitions for modification.

I. Background

Section 101(c) of the Federal Mine Safety and Health Act of 1977 (Mine Act) allows the mine operator or representative of miners to file a petition to modify the application of any mandatory safety standard to a coal or other mine if the Secretary of Labor (Secretary) determines that:

1. An alternative method of achieving the result of such standard exists which will at all times guarantee no less than the same measure of protection afforded the miners of such mine by such standard; or

2. That the application of such standard to such mine will result in a diminution of safety to the miners in such mine.

In addition, the regulations at 30 CFR 44.10 and 44.11 establish the requirements and procedures for filing petitions for modification.

II. Petition for Modification

Docket Number: M-2019-001-M.

Petitioner: Genesis Alkali, LLC, 1801 Wewatta St., Suite 1000, Denver, Colorado 80202.

Mine: Genesis Alkali @WESTVACO, MSHA I.D. No. 48-00152, located in Sweetwater County, Wyoming.

Regulation Affected: 30 CFR 57.22305 (Approved equipment (III mines)).

Modification Request: Petitioner seeks to allow for the installation of one or more submersible pumps at Westvaco mine. The first pump would be installed at Westvaco's Extraction Well #5 (EW#5).

The petitioner states that:

(1) Westvaco is an underground trona mine. Since 1988, underground tailings disposal and secondary resource recovery have been part of the mining operation. Sections of mine workings have been abandoned and flooded with water/tailings. There is no access to these areas by miners due to the topography of the mine. As the tailings dewater in the mine, the water becomes a solution that recovers trona left by the room and pillar mining techniques employed in these abandoned areas.

(2) Petitioner plans to install submersible pumps through wells from the surface to access this impounded trona-bearing liquor. The pumps will be strategically placed in the topographically lowest developments to ensure a flooded condition. Westvaco currently has monitor wells near these areas which indicate the areas are flooded with water completely. As further assurance of flooded conditions, the wells will be drilled through the mine floor to countersink the pumps an additional depth to ensure the pumps' intakes and motors remain below the mine floor. The pump motors, by design, are positioned below the pump intake to prevent the pump from drying the hole out. Specifically, the pump system's design ensures that the electrical components will be submerged, preventing their exposure to the mine's ambient air.

(3) The proposed pump system at Westvaco will be installed from the surface. The pump system(s) will be lowered underground via EW#5, into the northwest area of Westvaco that is permanently abandoned and has been inactive for more than twenty years. EW#5 is approximately 10,200 feet away from the nearest hoist and travelway. The distance between EW#5 and the areas of Westvaco where miners will be working and traveling is at least 15,000 feet, if not more.

(4) After the bore mining and longwall operations in the northwest corner of Westvaco had finished, petitioner intentionally flooded that area in the mid 1980s. By flooding that area, petitioner can engage in liquid/solution mining to recover trona from the gob. The topography of the mine area allows water levels in the flooded area to be deep enough to “top out” against the roof, effectively filling the entire region of the abandoned mine area. Along with this water barrier, petitioner installed barricades (stoppings) on the flooded area's perimeter. The barricades are comprised of 6″ x 8″ x 24″ wood blocks, installed rib-to-rib and floor-to-roof. Petitioner uses foam sealant around the edges of each barricade. Therefore, there are two physical designs—the wooden blocks and the impoundment—to prevent miners from accidentally or intentionally accessing the permanently abandoned area from the active longwall and bore miner operations.

(5) The submersible pump systems will be installed from the surface into the permanently abandoned, flooded areas. Westvaco miners will not be involved in the extraction of the trona solution because they cannot access the area due to the water levels and the barricades.

(6) The permanently abandoned area at Westvaco is not ventilated; therefore, the air current(s) at Westvaco do not flow through the area. In addition, there are several factors that would inhibit any accumulated methane that was in the abandoned area from entering the fresh air current at Westvaco.

These factors are:

—The impounded area is unventilated, meaning the airflow in that location will fluctuate as a function of temperature and pressures of the ambient air. This unventilated area borders the return air-courses of the active mine. Any gases that emit from the abandoned area will be carried to an exhaust vent shaft and removed from the mine—never reaching any active work areas or areas not already maintained to function in a gassy environment.

—Westvaco's active workings receive forced air from the surface. This mechanical ventilation creates a positive pressure environment that impedes the air in the impounded area from migrating through the barricades.

—The abandoned area is flooded, creating a liquid barrier between the submersible pump components and the ambient air.

(7) The physical design of the submersible pump system places the intake nozzle above the pump system's electrical components. The system's low water level shutoff sensor is a permissible component, and is positioned 15 feet above the pump's intake nozzle. The result of this design ensures that the electrical components will always be submerged, preventing their exposure to the ambient air. Because the non-permissible components will always be submerged, liquid barrier ensures that non-permissible equipment is not used in areas where methane may enter the air current.

(8) The pump system(s) will be in locations that are inaccessible by miners and the pumps operate autonomously, with remote control possible from the surface.

(9) Petitioner proposes to install autonomous equipment into a permanently abandoned area to support its milling activities on the surface. The petitioner states that if it is forced to undertake an alternative extraction method for the trona solution, the non-autonomous solution will likely require miners to be involved in the extraction which is less safe than an autonomous operation that only requires miners on the surface. The use of automated, submersible pump systems allows petitioner to avoid exposing miners to hazards associated with underground mining.

(10) The submersible pumps and technological upgrades that petitioner intends to install to perform liquid mining in underground impounded areas where no miners are present will provide a greater measure of safety than would be provided by having miners working in these areas who would then be exposed to the potential hazards of underground mining. Moreover, the use of automated, submersible pumps to transport a liquid trona solution to the surface for refining will not result in a diminution of safety compared to traditional underground mining activities.

The modification requested in this petition provides the same or greater degree of protection to persons underground as would be afforded by other methods of compliance and avoids reducing safety by the use of other methods.