I5i"«risi ii of All CarpoaraMoia

Transcription

1 I5i"«risi ii of All CarpoaraMoia Post Offic B :^ 180? TOfflls 84SSS-18? d Phone (001) gs9-5i3fl October 31, 1983 Mr. Edward R. Scherick Bureau of Land Management San Juan Resource Area P.O. Box 7 Monti cello, Utah RE: Rim Mine. Dear Mr. Scherick: I am writing in response to your letter dated October 25, 1983 con cerning the Plan of Operations for the above referenced mine. The additional information you requested on numerous items will be addressed individually by number below: 1. The only material that would possibly be buried upon final reclamation of this mine would be scrap metal and wood. If indeed this type of material is buried it will be dumped down the shaft prior to it's being sealed. 2. Enclosed please find a copy of "Atlas Minerals' Procedures for Sealing Boreholes, Shafts and Portals". This document was pre pared for and approved by the Division of Oil, Gas and Mining for all of Atlas' mines. 3. Atlas agrees to follow the guidelines for recontouring the waste dumps upon final reclamation as stated in your above mentioned letter. 4. If possible and practicable all roadways, parking areas and loading areas will be scarified to a depth of one foot upon final reclamation. 5. The seed mix contained in our approved Mining & Reclamation Plan filed with the Division of Oil, Gas and Mining is what we plan to use and is as follows: Crested Wheatgrass Intermediate Wheatgrass Yellow Sweetclover Fourwing Saltbush Smooth Brome 1 lb/acre 4 lb/acre 1 lb/acre 1 lb/acre 4 lb/acre

2 6. We feel the statement made in the Plan of Operations concerning closure of the water treatment ponds is adequate to satisfy all concerns. At this time it is uncertain as to which governing agency will be in charge of the activity and whether it will be on the State or Federal level. If no regulations are in place upon final reclamation this material will be buried under at least five feet of soil which is mutually acceptable to Atlas and appropriate regulatory agencies. 7. If this operation ever needs to expand onto undisturbed ground, an amendment will be filed at that time and topsoil concerns therein addressed. 8. If there is sufficient topsoil immediately adjacent to the site, it will be borrowed and distributed evenly over as much waste rock as possible upon final reclamation. I trust this information satisfies your concerns and will allow you to approve Atlas' Plan of Operation for the Rim Mine in a timely manner. Thank you for your cooperation and please contact me with any questions you may have. r Respectfully, Ricky J. Broschat Environmental Specialist RJB/jl Enclosure

3 ATLAS MINERALS PROCEDURES FOR SEALING BOREHOLES, SHAFTS, AND PORTALS Prepared for the DOOM By: Patrick R. Lorello Envrionmental Technician Atlas Minerals

4 TABLE OF CONTENTS SEALING PROCEDURES: Pagg No. 1. Boreholes l II. Portals 4 III. Shafts 5 DIAGRAMS: I. Boreholes 2. 3

5 I. PROCEDURE FOR BOREHOLE SEALING Boreholes used by Atlas Minerals for the ventilation of under ground workings vary in diameter from 8 inches to 60 inches. Bore holes are either steel cased the entire^^jength of the borehole or the casing extends approximately 20 to 30 feet beneath the surface. Whether a borehole is cased entirely or only cased near the surface depends on the nature of the subsurface material. If the subsurface material is determined to be stable (i.e. sloughing of hole will not occur,, and no water bearing strata was encountered) then casing will only be placed near the surface, if the subsurface material is unstable the borehole will be cased its entire length. Any water bearing strata encountered is expected to be sealed by the borehole casing, no water bearing strata are encountered in boreholes which have been determined to be stable. The following description and diagrams list the recom mended procedures to be followed for borehole sealing. A. Where applicable the cement pad surrounding the borehole shall be broken up and placed into the borehole, as illus trated in diagram A. B. If the surface surrounding the borehole is loose, the loose surface material shall be excavated to allow room for the casing to be cut approximately three feet beneath the ground surface (see diagram B). If the surface surrounding the borehole is solid rock, the casing shall be cut level with the exposed rock. C. A steel plate shall be placed on top of the borehole and welded to the casing (see diagram C). The plate shall be of sufficient size and strength to protect the integrity of the surface contours. D. Where applicable, material previously excavated will be placed back on top of the sealed borehole and regraded to natural contours, as shown in diagram D. -1-

6 50-1hole orcfv^iniei rr lupfa.ce rt f CEMEfiT?hZ> CEMENT PAD li:li-.l!l GROUND,. teveu j; r WMWh!! I f!:j!:!^ :!-rrn^r -n /! V 'I i ;. il f t i. t :>!/! I I' li'jli I'i^^! ' ' 'Jj!i ground Ty //LEVEL /, SUBSURFACE - CASING A. CEHENT PAD BROKEN UP AND REP10VEO. MATERIAL _ EXCAVATED 'IliU'llHij STEEL PLATE :!! Il'l, 7//7'//-7// /' '.i'hh 'i 7r^'i n ijiiiltffliliil.. > ' i 8. LC05E mierlal REHOVED AND CASIMG CUT. C STEEL PLATE WELDED IN PLACE. %> /

7 I -i Wimik > 'I =ii!!' hii nr 1 D. SURFACE RECRAOED TO NATURAL CONTOURS.

8 n. PROCEDURE FOR PORTAL SEALING Atlas Minerals uses portals as surface entrances to addits or declines to access underground workings. The average portal dimension is 9 feet X 12 feet. Sealing procedu-i^es for portals are discussed for two portal categories. The first portal category involves portals that have their entrance locations adjacent to level ground. Sealing procedures shall utilize the surrounding waste rock to backfill the entrance, pushing as much waste rock into the opening as possible. The waste rock shall then be sloped to prevent surface drainage from entering the sealed portal. The second portal category involves portals that have their entrance locations above level ground (e.g. portal entrances in cliffs), or portal entrance locations where it would not be feasible to backfill. Sealing procedures shall utilize explosive charges placed around the portal perimeter to seal the portal entrance. -4-

9 III. PROCEDURE FOR SHAFT SEALING Mine shafts used by Altas Minerals as vertical access to under ground workings, will be sealed according to the following description, Associated superstructure will be removed from the shaft opening, primarily the headframe, hoisting works, backlog structures, and the concrete pad. The shaft will be backfilled using the surrounding waste rock until the waste rock reaches the ground surface. C. Once the waste rock reaches ground level the surface will be graded to match existing surface contours, and prevent surface drainage from entering the sealed shaft. -5-