Petition for Modification
In the matter of
San Juan Coal Company
San Juan South Mine
I.D. No. 29-02170
San Juan Deep Mine
I.D. No. 29-02201
Docket No. M-2000-106-C
30 CFR 75.1700
On July 31, 2000, a petition was filed seeking a modification of the application of 30 CFR 75.1700 to Petitioner's San Juan South and San Juan Deep Mines, located in San Juan County, New Mexico. 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.
The alternative method proposed by the petitioner is similar to that approved under similar petitions for modification; however, MSHA has added certain terms and conditions. Specifically, these additional terms and conditions include the District Manager's authority to allow mining within the 300-foot barrier pillar without plugging and to accept wells cleaned and plugged prior to the effective date of this Order, if the plugging methods are documented and meet the terms and conditions of this Order.
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.
The alternative method proposed by the Petitioner (as amended by MSHA) will at all times guarantee no less than the same measure of protection afforded the miners under 30 CFR 75.1700.
The petitioner stated during MSHA' investigation that there are 24 gas well safety barriers which might be intersected at these mines. Of these 24, the petitioner stated only two gas wells are expected to remain active up to the time of plugging and cut-through. The San Juan South and San Juan Deep Mines operate in the Fruitland No. 8 Coal Seam, located approximately 100 feet below the Fruitland No. 9 Coal Seam. Any seam greater than 24 inches must be treated as if it will be mined. If the petitioner obtains information concerning the location of any additional gas wells, the terms and conditions of this PDO will apply to those wells. If the petitioner acquires additional property at the San Juan South and San Juan Deep Mines, the terms and conditions of this PDO shall apply, unless the existing records show that an abandoned well was plugged using techniques equivalent to those contained in the terms and conditions of this PDO, and that information is submitted and accepted in accordance with
Paragraph 2(s) as providing the required level of safety by the District Manager, the well shall be again cleaned, inadequate plugging materials drilled out and the well plugged in accordance with the terms and conditions of this PDO before such wells may be cut through or approached within the allowed limits.
MSHA suggests that special attention to securing and interpreting the suite of drill logs required by Paragraph 1(a)(4) is needed to assure that, at a minimum, the expanding cement plug extends from at least 200 feet below the lowest mineable seam through 100 feet above the highest mineable seam, unless the seams are separated by an interval greater than 300 feet, in which case each seam may be plugged individually.
On the basis of the petition and the findings of MSHA's investigation, San Juan Coal Company is granted a modification of the application of 30 CFR 75.1700 to its San Juan South and San Juan Deep Mines.
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 San Juan Coal Company's Petition for Modification of the application of 30 CFR 75.1700 in the San Juan South and San Juan Deep Mines is hereby:
GRANTED, for mining through or near (whenever the safety barrier diameter is reduced to a distance less than the District Manager would approve pursuant to Section 75.1700) plugged oil or gas wells penetrating the Fruitland No. 8 Coal Seam and other mineable coal seams, conditioned upon compliance with the following terms and conditions:
1. Procedures to be utilized when plugging oil or gas wells.
a. Cleaning out and preparing oil and gas wells. Prior to plugging an oil or gas well, the following procedure shall be followed:
(1) A diligent effort shall be made to clean the borehole to the original total depth. If this depth cannot be reached, the borehole shall be cleaned out to a depth which would permit the placement of at least 200 feet of expanding cement below the base of the lowest mineable coalbed.
(2) When cleaning the borehole, a diligent effort shall be made to remove all the casing in the borehole. If it is not possible to remove all casing, the casing which remains shall be perforated, or ripped, at intervals spaced close enough to permit expanding cement slurry to infiltrate the annulus between the casing and the borehole wall for a distance of at least 200 feet below the base of the lowest mineable coalbed.
(3) If the cleaned-out borehole produces gas, a mechanical bridge plug shall be placed in the borehole in a competent stratum at least 200 feet below the base of the lowest mineable coalbed, but above the top of the uppermost hydrocarbon-producing stratum. If it is not possible to set a mechanical bridge plug, a substantial brush plug may be used in place of the mechanical bridge plug.
(4) A suite of logs shall be made consisting of a caliper survey, directional deviation survey, and log(s) suitable for determining the top and bottom of the lowest mineable coalbed and potential hydrocarbon producing strata and the location for the bridge plug.
(5) If the uppermost hydrocarbon-producing stratum is within 200 feet of the base of the lowest mineable coalbed, properly placed mechanical bridge plugs or a suitable brush plug described in Subparagraph (a)(3) shall be used to isolate the hydrocarbon producing stratum from the expanding cement plug. Nevertheless, a minimum of 200 feet of expanding cement shall be placed below the lowest mineable coalbed.
(6) The well bore shall be completely filled and circulated with a gel that inhibits any flow of gas, supports the walls of the borehole, and increases the density of the expanding cement. This gel shall be pumped through open-end tubing run to a point approximately 20 feet above the bottom of the cleaned out area of the borehole or bridge plug.
b. Plugging oil or gas wells to the surface. The following procedures shall be utilized when plugging gas or oil wells to the surface:
(1) A cement plug shall be set in the well bore by pumping an expanding cement slurry down the tubing to displace the gel and fill the borehole to the surface. (As an alternative, the cement slurry may be pumped down the tubing so that the borehole is filled with Portland cement or a Portland cement-fly ash mixture from a point approximately 100 feet above the top of the lowest mineable coalbed to the surface with an expanding cement plug extending from at least 200 feet below the lowest mineable coalbed to the bottom of the Portland cement.) There shall be at least 200 feet of expanding cement below the base of the lowest mineable coalbed.
(2) A surface casing or a small quantity of steel turnings, or other small magnetic particles, shall be embedded in the top of the cement near the surface to serve as a permanent magnetic monument of the borehole.
c. Plugging oil or gas wells using the vent pipe method. The following procedures shall be utilized when using the vent pipe method for plugging oil and gas wells:
(1) A 4-½ or larger vent pipe shall be run into the well bore to a depth of 100 feet below the lowest mineable coalbed and swedged to a smaller diameter pipe, if desired, which will extend to a point approximately 20 feet above the bottom of the cleaned out area of the borehole or bridge plug.
(2) A cement plug shall be set in the well bore by pumping an expanding cement slurry, Portland cement, or a Portland cement-fly ash mixture down the tubing to displace the gel so that the borehole is filled with cement. The borehole and the vent pipe shall be filled with expanding cement for a minimum of 200 feet below the base of the lowest mineable coalbed. The top of the expanding cement shall extend upward to a point approximately 100 feet above the top of the lowest mineable coalbed.
(3) All fluid shall be evacuated from the vent pipe to facilitate testing for gases. During the evacuation of fluid, the expanding cement shall not be disturbed.
(4) The top of the vent pipe shall be protected to prevent liquids or solids from entering the well bore, but permit ready access to the full internal diameter of the vent pipe when necessary.
d. Plugging oil and gas wells for use as degasification boreholes. The following procedures shall be utilized when plugging oil or gas wells for subsequent use as degasification boreholes:
(1) A cement plug shall be set in the well bore by pumping an expanding cement slurry down the tubing to displace the gel and provide at least 200 feet of expanding cement below the lowest mineable coalbed. The top of the expanding cement shall extend upward to a point above the top of the coalbed being mined. This distance shall be based on the average height of the roof strata breakage for the mine.
(2) To facilitate methane drainage, degasification casing of suitable diameter, slotted or perforated throughout its lower 150 to 200 feet, shall be set in the borehole to a point 10 to 30 feet above the top of the expanding cement.
(3) The annulus between the degasification casing and the borehole wall shall be cemented from a point immediately above the slots or perforations to the surface.
(4) The degasification casing shall be cleaned out for its total length.
(5) The top of the degasification casing shall be fitted with a wellhead equipped as required by the District Manager. Such equipment may include check valves, shut-in valves, sampling ports, flame arrestor equipment, and security fencing.
e. Special conditions for plugging gas wells in the Fuitland Coal Beds:
- The Petitioner shall identify the lowest and highest coal seams exposed in each well. Even if the exposed seam will not be mined, all coal seams shall be plugged in accordance with Paragraphs (a), (b), (c), or (d), outlined above.
- The petitioner shall assure that the coal seams immediately above and below the Fruitland No. 8 Seam are plugged in accordance with this PDO and that any existing records are accurate and complete.
2. The following cut-through procedures (a-t) apply whenever the petitioner reduces the safety barrier diameter to a distance less than the District Manager would approve pursuant to Section 75.1700 or proceeds with an intent to cut through a plugged well:
a. Prior to mining within 300 feet of the well or reducing the safety barrier to a distance less than the District Manager would approve pursuant to Section 75.1700 or proceeding with an intent to cut through a plugged well, the operator shall notify the District Manager or his designee
.b. The MSHA District Manager or designee shall conduct a conference prior to mining through any plugged well to review the specific procedures for mining through the well as set forth in this PDO. Representatives of the operator, the representative of the miners, and the appropriate State agency shall be informed, within a reasonable time prior to the conference, and be given an opportunity to attend and participate. This meeting may be called by the operator and may be conducted by teleconference.
c. Mining through a plugged well shall be done on a shift approved by the District Manager or designee.
d. The District Manager or designee, representative of the miners, and the appropriate State agency shall be notified by the operator in sufficient time prior to the mining through operation in order to have an opportunity to have representatives present.
e. When using continuous mining equipment, driveage sights shall be installed at the last open crosscut near the place to be mined to ensure intersection of the well. The driveage sites shall not be more than 50 feet from the well. When using longwall mining methods, driveage sights shall be installed on 10-foot centers for a distance of 50 feet in advance of the well bore. The driveage sights shall be installed in the headgate and tailgate.
f. Firefighting equipment, including fire extinguishers, rock dust, and sufficient fire hose to reach the working face area of the mining through shall be available when either the conventional or continuous mining method is used. The fire hose shall be located in the last open crosscut of the entry or room. All fire hoses shall be ready for operation during the mining through. When the longwall mining method is implemented, the fire hose shall be expended to the face area of the mine-through. All fire hoses shall be ready for operation during the mine through.
g. Sufficient supplies of roof support and ventilation materials shall be available and located not more than two crosscuts outby the mining-through location. In addition, an emergency plug and/or plugs shall be available in the immediate area of the cut through.
h. At least the quantity of air required by the approved mine ventilation plan, but not less than 6,000 cubic feet of air per minute for scrubber equipped continuous miners or not less than 9,000 cubic feet per minute for continuous miner sections using auxiliary fans or line brattice only, shall be used to ventilate the working face during the mining through operation. The quantity of air required by the ventilation plan, but not less than 30,000 cfm, shall reach the working face of each longwall during the mine-through operation.
i. Equipment shall be checked for permissibility and calibration and serviced prior to each shift mining is conducted within a 300 foot-radius of a well plugged for cut through, prior to mining through the well and the water line maintained to the tail piece with a sufficient amount of fire hose to reach the farthest point of penetration on the section.
j. The methane monitor(s) on the continuous mining machine or the longwall shear and face shall be calibrated on the shift prior to mining through the well.
k. When mining is in progress, tests for methane shall be made with a hand-held methane detector at least every 10 minutes from the time that mining with the continuous mining machine is within 30 feet of the well until the well is intersected and immediately prior to mining through. When mining with longwall mining equipment, the tests for methane shall be made at least every 10 minutes when the longwall face is within 30 feet of the well. During the actual cutting through process, no individual shall be allowed on the return side until mining through has been completed and the area has been examined and declared safe.
l. When using continuous mining methods, the working place shall be free from accumulations of coal dust and coal spillages, and rock dust shall be placed on the roof, rib and floor to within 20 feet of the face when mining through, or near the well on the shift or shifts during which the cut through will occur. On longwall sections rock dusting shall be conducted and placed on the roof, rib, and floor (excluding the actual face from which coal is being cut) up to both headgate and tailgate gob.
m. When the well bore is intersected, all equipment shall be deenergized and the place thoroughly examined and determined safe before mining is resumed. Any well casing shall be removed and no open flame shall be permitted in the area until adequate ventilation has been established around the well bore.
n. After a well has been intersected and the working place determined safe, mining shall continue inby the well a sufficient distance to permit adequate ventilation around the area of the well bore.
o. No person shall be permitted in the area of the mining through operation except those actually engaged in the operation, company personnel, representatives of the miners, personnel from MSHA, and personnel from the appropriate State agency.
p. The mining through operation shall be under the direct supervision of a certified official. Instructions concerning the mining through operation shall be issued only by the certified official in charge.
q. MSHA personnel may interrupt or halt the mining through operation when it is necessary for the safety of the miners.
r. A copy of this PDO shall be maintained at the mine and be available to the miners.
s. The Petitioner shall file a plugging affidavit setting forth the persons who participated in the work, a description of the plugging work, and a certification by the Petitioner that the well has been plugged as described.
t. 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 include initial and refresher training regarding compliance with the terms and conditions stated in 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.
_________________________________
Michael J. Lawless
Deputy Administrator
for Coal Mine Safety and Health
