Part 817 contains the minimum performance standards and design criteria which would be applicable under a State or Federal program for underground mining activities. The organization of this Part parallels that of Part 816, the standards for surface mining, although some modifications were needed to reflect the distinct differences between surface and underground coal mining, including entirely new Sections for subsidence (Sections 817.121 817.126).

SECTION 817.1.

Scope.

Two commenters felt that Section 817.1 should be revised to encompass only surface operations and surface impacts incident to an underground coal mine. Section 507(b)(11) of the Act specifically authorizes concern for groundwater systems, and the Act is explicitly concerned about subsidence which results from underground mining techniques. Accordingly, the language of the regulations as proposed has been retained for complete scope of coverage.

SECTION 817.2.

Objectives.

The objectives are derived from Sections 102 and 516 of the Act.

SECTION 817.11.

Signs and markers.

This Section is substantially identical to Section 816.11, the corresponding Section of Part 816. The reader is referred to the portions of this preamble which discuss Section 816.11 for information concerning the technical basis and statutory authority for this Section. In addition to the Sections of the Act cited in those portions of the preamble, this Section is based on Section 516 of the Act. All comments and issues addressed in regard to Section 816.11, were also considered and similarily disposed of in preparing Section 817.11. Comments received on specific Paragraphs of Section 817.11 are addressed below:

Paragraph (d). Several commenters felt that the requirement for perimeter markers should be deleted in its entirety. The requirement for the use of perimeter markers is found in Section 701(17) of the Act. Several other commenters felt that Paragraph (d) should be amended. Surface perimeter markers above underground workings will not aid underground operations to stay within their permit areas, except for the surface operations and facilities associated with the mine. In addition, before mining the exact geographic location on the surface of the openings in an underground mine may be unknown or subsequently may be changed for purposes of avoiding bad ground, providing watertight closure, or for other unexpected conditions. Accordingly, paragraph (d) was amended to require persons who conduct underground mining activities to mark only the perimeter of all areas affected by surface operations or facilities. If the perimeters of such areas change, the perimeter markers must be adjusted accordingly.

Paragraph (e). Three commenters felt that buffer zone markers should be deleted in their entirety. While buffer zone markers may be applicable to surface activities, there appears to be no practical justification for markers in underground workings. Section 817.57(b) states that the areas not to be disturbed shall be designated a buffer zone and marked as specified in Section 817.11. Paragraph (e) was amended, and now requires buffer zones referred to in Section 817.57 to be clearly marked on the surface only to prevent disturbance by surface activities incident to underground mining. Underground marking is not required.

Paragraph (f). Many commenters felt that Paragraph (f) should be revised so as not to require marking surface areas with blasting signs over underground blasting, on the grounds that this may not be possible due to ownership of surface, and the surface effects of underground blasting would be minimal. The purpose of a blasting sign is to protect people who may inadvertently wander into the blast area. Inside an underground mine this is unlikely, due to other measures required to protect the opening to the mine. In addition, surface signs will do little to warn persons underground. Blasting that occurs on the surface at an underground mine will require appropriate warning devices and signs. Paragraph (f) was revised to reflect that it is limited to surface blasting.

SECTIONS 817.13-817.15 Casing and sealing of drilled holes.

These Sections are intended to ensure that boreholes, shafts, wells, and other accesses to underground mines are sealed, filled, cased, lined, or protected so as to ensure and protect the health, safety, and general welfare of the public, the quality of the environment, and potential land uses.I11Authorities for these Sections are found in Sections 102, 201, 501, 503, 504, 507, 508, 516, 517, 701 and 717 of the Act.

{15263}Following is a list of the technical literature used in the preparation of these performance standards:

1. Ciolkosz, E. J., and others 1973. Soil as a medium for the renovation of acid mine drainage. Office of Water Resources Research December 1973.

2. Doyle, William S. 1967. Mine sealing, deep coal mining_waste disposal technology. Noyes Data Corporation, Park Ridge, N.J.

3. Garrett, W. S., and Pitt, L. T. C. 1961.

Design & construction of underground bulkheads and water barriers, in 7th Commonwealth Mining & Metalurgical Congress, Johannesburg, South Africa. Vol. 3, 1283 1301.

4. U.S. Dept. of the Interior, Federal Water Quality Administration, 1970. New mine sealing techniques for water pollution abatement.

Haliburton Co., 163 pp.

5. Penrose, Jr., et al., EPA 68 010135. 1973. Laboratory study of self-sealing limestone plugs for mine openings. EPA 43019 73 011.

6. HRB-Singer, Incorporated. April 1971. Detection of abandoned underground coal mines by geophysical methods. Environmental Protection Agency and the Pennsylvania Department of Environmental Resources, Project 14010EHN.

7. Moebs, N. N. & Krickovic, S. 1970. Air sealing coal mines to reduce water pollution. BOMRI 7354.

8. Penrose, R. G., Jr., and Holubec, Igor, 1973. Laboratory study of self-sealing limestone plugs for mine operations. EPA 670/2 73 081.

9. Stoddard, C. K. 1973. Abatement of mine drainage pollution by underground precipitation. EPA 67012 73 092.

10. U.S. Environmental Protection Agency. 1973. Processes, activities, EPA 43019 73 011.

11. U.S.E.P.A. 1975. Criteria for developing pollution abatement programs for inactive and abandoned mine sites. EPA 440 9 75 008.

Sections 817.13 and 817.15 require that exploration holes or other underground openings be cased, sealed, or otherwise managed "as approved by the regulatory authority.'' The decision to amend the proposed regulations by insertion of the phrase "as approved by the regulatory authority,'' thus giving the regulatory authority wide latitude in the management and disposition of exploratory holes, shafts, wells, drifts, and other underground openings, was made on the basis of comments discussed below and for the following additional reasons:

These Sections provide for the sealing or managing of openings to prevent people and animals from entering the opening thereby reducing the safety hazards associated with unsecured underground openings. The casing and sealing requirements of these Sections will aid in protecting water resources and the prevailing hydrologic balance by preventing or controlling the discharge of acid mine water. The formation of acid water is a naturally occurring phenomenon which results from the oxidation of iron pyrites in the presence of water and air. Coal mining operations disturb the soil, rock material, and coal bed, thereby exposing the iron pyrites which can greatly enhance the formation of acid drainage. The acid water draining from the coal mine enters streams and greatly reduces the useability of these waters for human or industrial consumption. Sealing of openings is one method of controlling the production of acid water from mines. Abandoned drift mines generally can be sealed, enabling the flooding of a mine and thus stopping the oxidation of pyrite. (Doyle, 1976, p. 9 and Moebs, 1970, pp. 1 3, 16 20.) Sealing will also reduce the formation of acid water by preventing the entrance and flow of water and air into and out of the mine.

Many different types of sealing techniques were considered in the development of these Sections. No specific technique is universally acceptable in the literature for sealing all underground openings. (Doyle, 1976, pp. 19 32 and Halliburton, Co., 1970, pp. 5 6, 9 10, 20 21.) Mine sealings may involve construction of a physical barrier across a mine opening to prevent passage of air, water, or persons and wildlife. The ultimate water level behind the seal is, however, seldom controlled, and excessive pressure can build up, resulting in a mine seal blow-out. Sudden release of large quantities of water can have devastating downstream effects. (Doyle, 1976, p. 19. See Commonwealth v. Barnes and Tucker Co., 452 PA., 77, (1974).) Mine seals may be designed to retain large quantities of water, but seal leakage and failures generally occur from natural zones of weakness such as outcrop fractures. The natural rock and mineral surrounding the seal area is usually fractured, fissured, uneven, or unstable. As adopted, the regulations require that the seal must prevent the flow of water from the openings, except as otherwise authorized by the regulatory authority. Regulatory authorities should have the latitude to require the design of sealing and monitoring programs on a mine-by-mine basis so that catastrophic plug failures are prevented. Of course, if drainage from underground working is unavoidable, despite the use of the best available methods of sealing, then the resulting discharge to surface or groundwater must be controlled so as to achieve the applicable effluent limitations.

As evidenced above, the wide variety of situations likely to be encountered with regard to the managing of various underground openings make it appropriate that the regulatory authority be given discretion in what it may or may not require in properly managing these openings. Accordingly, the proposed regulations were modified by inserting the phrase "as approved by the regulatory authority'' where appropriate.

Numerous comments received on these Sections also indirectly influenced the decision to provide the regulatory authority with greater latitude in dealing with the management of holes, wells, and underground openings.

1. Several commenters objected to the proposed regulations requiring the permanent sealing or closing of drilled holes or wells, stating that in many cases such holes or wells could prove useful to surface owners as a water wells, or to an operator as water monitoring wells. One of the commenters stated that often permission to test drill on private land was contingent on leaving a water well for future use by the land owner. Some commenters suggested that the regulations by revised to allow more flexibility in the use of drilled holes and wells. These suggestions were accepted, with the request for more flexibility evolving into greater latitude for the regulatory authority, as well as the language dealing with the requirements for transfer of water wells being added to the appropriate Sections, to provide a complete picture of the requirements applicable to these openings.

2. One commenter objected to the proposed provisions of Section 817.13 requiring an underground operator to permanently close each borehole or well in the permit area, stating that this could be an extremely expensive operation for the operator with little or no actual benefit to the environment or public safety. The rationale presented by the commenter was sound. Accordingly, the comment was accepted and the regulations were changed to require the closing of only those holes uncovered or exposed by mining activities. Holes already on the site and unaffected by the operation need not necessarily be sealed, except those which may require sealing to minimize disturbance to the hydrologic balance of the area being mined.

3. Sections 816.14 and 817.14(b) deal with the temporary casing and sealing of drilled holes. One commenter suggested modification of this provision to include additional exceptions for (drill) holes which will be removed in whole or in part by subsequent mining. This comment was rejected on the basis that this Section deals specifically with two types of holes: (a) holes used to return coal processing waste or water to underground workings, and (b) holes used to monitor ground water. Both must have been specifically identified in the approved permit. As both types of holes have a specific function, there is no justification for waiving the requirements that they be sealed temporarily before use and protected during use. The importance of these holes is such that it would be to the operator's advantage to take all possible care in their location, and to ensure that they are securely cased and protected from damage. Leaving a proposed disposal well or monitoring well uncased and unprotected invites loss of the well before the end of its usefulness, and the subsequent cost of redrilling the well as required under the approved permit. Similarly, leaving a disposal well uncased would probably allow leach ate from the coal processing waste or water access to porous rock or aquifers above the disposal area, and cause possible significant harm to the hydrologic balance of the area resulting from this access. Leaving a monitoring well uncased could allow toxic surface runoff or toxic groundwater generated by the mine operation access to the groundwater being monitored, again resulting in possible significant harm.

{15264}Finally, locating these holes in an area where they would soon be removed by mining would in most cases be an unsound procedure in view of the importance of these holes, and the importance of their proper casing and maintenance as explained above.

4. Section 817.14(a) provides that all mine entries which are temporarily inactive but have a projected useful service be barricaded, fenced, and posted to identify the hazardous nature of the opening. Specific standards for barricades and construction materials to protect the mine entries were considered in the formulation of the regulation. However, the Office elected to provide generalized standards for mine entry protection.

The regulations also require that protective devices be periodically inspected and maintained in good operating condition. Various inspection periods were considered in the formulation of the regulations, but no set time period (e.g., monthly, weekly basis) was included because the inspection period depends on the hazard of opening, type of protective device, and condition of the opening. The number of inspections must be frequent enough to ensure that the protective devices are in good operating condition and safe.

5. One commenter suggested deletion of this Section, as well as Sections 817.13 and 817.15, on the basis that these regulations would be a duplication of existing MSHA regulations. This comment was rejected. Section 702(a)(2) of the Act states that nothing in the Act shall be construed as superceding, amending, modifying, or repealing the Federal Coal Mine Health and Safety Act of 1969 (83 Stat. 742). Sections 816.13 through 816.15 were proposed to protect the health, safety, and general welfare of the public, the quality of the environment, and potential land uses. MSHA requirements are aimed primarily at protecting mine worker safety. OSM believes that these regulations are complementary and do not supersede or modify the MSHA regulations.

SECTIONS 817.21-817.25 Topsoil

These Sections are intended to assure that persons conducting underground mining activities remove topsoil or other plant growth material prior to operations, store it for later use as a plant root medium and redistribute it in a manner that will protect, as much as possible, its productivity.

Authority for these Sections is found in Sections 102, 201, 501, 503, 504, 507, 508, 515, and 516(b)(10) of the Act. In response to public comments, these regulations differ from those for surface mining where comments were substantive enough to warrant different performance standards.

Section 817.21 sets forth the general requirements for handling topsoil. It requires that topsoil and subsoil be separately removed, saved, and segregated from other materials. When removed, the topsoil shall be immediately redistributed or stockpiled for redistribution at a later time except when the permittee can demonstrate to the regulatory authority that an alternative procedure will provide equal or more protection to the topsoil.

1. A number of commenters contended that the requirements for removal, storage and subsequent redistribution of topsoil were not supportable because of the extended periods of time (20 to 40 years) that will be required for storage. It was argued that the value of stockpiling topsoil for long periods of time is unknown and unlike surface mining, the disturbed area of an underground mine remains disturbed for a number of years, thus the stockpiled material will lose fertility, or organic matter and other desirable characteristics that were present when the material was stored. Since fertility losses, for example, nitrogen lost due to leaching, can be restored with additions of fertilizer (Vogel and Berg, 1973, pp. 189), organic matter can be restored with additives and micro-organisms lost during the stockpiling period will regenerate quickly when surface soil layers are returned to the surface (McCormack, 1974, pp. 151). The regulations were changed only to accommodate those occasions when the permittee demonstrates to the satisfaction of the regulatory authority that an alternative procedure will provide equal or more protection for the topsoil and the use of that alternate procedure is approved by regulatory authority.

2. Other changes in this section of the regulations are discussed in the Preamble for Section 816.21 because public comments were essentially identical; hence, to avoid redundance the reader is referred to the discussion contained in that section. The Office believes that Sections 817.22, 817.23, 817,24, and 817.25 should be substantially identical to the corresponding Sections of Part 816 since there are no identifiable distinctions between the functions of these Sections. The reader is referred to the appropriate Sections of the Preamble of Part 816 for information and discussion on the regulations of the Sections of the regulation of Part 817.

SECTIONS 817.41-817.57 Hydrologic Balance.

Introduction

With the exception of Section 817.50, all of these proposed Sections are substantially similar to their corresponding Sections in Part 816. The reader is referred to the appropriate portions of the Preamble for Part 816 for information concerning the technical basis, alternatives considered, and statutory authority. In addition to the Sections of the Act cited in those portions of the Preamble, these Sections of Part 817 are based on Section 516 of the Act. The Office considers effects on the hydrologic balance sufficiently similar in surface and underground mining to warrant substantially similar performance standards, except for the differences noted in the following discussion.

SECTION 817.41 Hydrologic Balance: General Requirements.

1. Legal authority for this section is Section 516 of the Act and those provisions cited in the preamble to Section 816.41. That portion of the Preamble presents a detailed explanation of the basis and purpose of most of the similar provisions of 817.41. However, some differences between surface and underground mining activities were noted, leading to some different provisions for Section 817.41.

2. A commenter believed that the regulations failed to adequately address basic differences between surface and underground coal mining operations. No specific changes in the performance standards were recommended by the commenter and without which the Office had no basis to evaluate the commenter's opinion. The Office considers the effects of many mining activities on the hydrologic balance to be sufficiently similar in surface and underground mining to warrant many substantially identical requirements under Sections 816.41 and 817.41, although the magnitude of effects may be quite diverse because of the differences between the operations. Because of those differences specification of differing requirements has been made in Sections 816.41(d)(2)(viii) and 817.41(d)(2)(viii) (xi) to account for differences of underground activities. The magnitude of hydrologic impacts of underground mining activities is described at the final EIS, pages B III 37 38, at USEPA, 1976 (a) pp. 51 57; pp. 88 94; and at Hill and Bates 1978, pp. 5 11 and 15 16.

{15265}3. A commenter thought that the word "prevent'' in Section 817.41(a) should be replaced by "minimize.'' The Office rejected this change, because the intent of Congress was to prevent long-term adverse changes in the hydrologic balance with respect to all operations in an affected area (see Section 516(b)(9)(B) of the Act).

4. Another commenter thought that Section 817.41(d)(2)(x) was inconsistent with Section 516(b)(1) of the Act. The Office rejected this comment, because the regulation does not absolutely require subsidence prevention as the commenter asserted, but merely subsidence control, as implemented through 30 CFR 817.50, 187.121 817.128.

5. A few commenters believed that Section 187.41(d)(2)(xi) was inconsistent with Section 516(b)(9) of the Act, by requiring prevention, rather than "minimizing'', of acid mine drainage. However Section 516(b)(9) of the Act clearly requires the operator to minimize the disturbances to the hydrologic balance by: " avoiding acid or toxic mine drainage . . .'' Consequently, the Office rejected the comment because the Act requires prevention of acid mine drainage. Further, Section 516(b)(12) of the Act prohibits gravity discharge of water from new drift mines working acid-producing or iron-producing coal seams.

6. Additional comments and issues relating to this Section that are identical to those raised as to Section 816.41 are discussed under the preamble to that Section.

7. Additional minor editorial changes to improve clarity from the proposed rules were made by the Office and were nonsubstantive in nature.

SECTION 817.42 Hydrologic balance: Water quality standards and effluent limitations.

A. Introduction

1. Legal authority for this Section is Section 516 of the Act and those provisions cited in the preamble to Section 816.42. That portion of the preamble presents a more detailed explanation of the general basis and purpose of most of the specific provisions established in this Section.

2. This Section specifies water pollution control collection and treatment requirements, and contains minimum water quality standards and effluent limitations for underground coal mining activities. A general discussion of the purposes and objectives of this Section was at 43 FR 41744 41746 (September 18, 1978). To provide clarity to the reader, the Section was restructured from the proposed version to include discrete alphanumeric paragraphs.

3. Surface effects of underground mining and underground mine workings may result in adverse effects on surface water systems (USEPA, 1976 (a) at 88). These effects may result from acid mine drainage flow into streams (H.R. Rep. No. 95 218. 95th Cong., 1st Sess. at 58, 1977; Kosowski, 1973, 83 pp.; Caruccio, 1968 at 107 151; Musser, 1965 at sheet 4) from subsidence of the land surface or underground workings which allows surface drainage to be diverted into mine workings (Dunrud, 1976 at 2 and 34), and from erosion and water quality degradation as a result of waste material removed from the workings and placed on the surface facilities.

Water pollution control for underground coal mining operations is largely restricted to at-source methods for reducing water inflow into the mine workings and to treatment of collected mine drainage and surface runoff. Generally water quality analyses have not indicated significant differences between untreated waste water from surface and underground operations in similar geologic settings. (USEPA, 1976 (a) at page 53). Therefore, as required in EPA's Effluent Limitation Guidelines for the Coal Mining Point Source Category (40 CFR 434), the same numerical discharge limitations apply to surface and underground coal mining operations. These effluent limitations, with appropriate modifications to meet the intent of the Act, have been incorporated into Section 817.42(a)(2).

4. The preamble to Section 816.42 describes the general provisions relating to water quality standards and effluent limitations, which essentially parallel those of Section 817.42. Some differences exist between the nature of discharges (i.e., principally source and duration) between surface and underground coal mining operations.

First, as an alternative to passing all surface drainage and waters from underground workings through a sedimentation pond or series of sedimentation ponds, Section 817.42(a) allows for use of a "treatment facility'' (e.g., a package neutralization device). Due to the fact that some operations may have very limited surface facilities and waters from the mine workings may have very low total suspended solids concentrations, the use of a sedimentation pond may not be necessary and a small-scale treatment facility may be best suited for treating discharges from coal mining operations to meet applicable effluent limitations.

With respect to the criteria for the removal of sedimentation ponds and treatment facilities, Section 817.42 includes criteria similar to Section 816.42 for surface drainage; however, for discharges from underground workings, Section 817.42 also requires that sedimentation ponds and treatment facilities remain in place until either the discharge continuously meets the effluent limitations without treatment or until the discharge has permanently ceased. This additional requirement is necessary, given the potential for long-term discharges of waters from underground workings, principally by gravity drainage. See H.R. Rep. No. 95 218, 95th Cong., 1st Sess. at 127 (1977).

Differences between the two Sections also exist with regard to the exemption to the requirement for use of sedimentation ponds or treatment facilities to treat surface drainage. Section 817.42 not only requires the discharge to show that such ponds or facilities are not necessary to meet effluent limitations or applicable State and Federal water quality requirements and that the disturbed, surface drainage area within the total disturbed area is "small,'' but also that there is no mixture of surface drainage with discharges from the underground mine workings. For exemptions to the treatment of discharges solely from underground mine workings, Section 817.42 requires that a demonstration be made that treatment is not necessary to meet the effluent limitations or applicable State and Federal water quality requirements and that there is no mixture of drainage from underground workings with drainage from surface areas. These additional criteria for the exemption to the requirement for sedimentation ponds or treatment facilities provides that mixing of waters with potentially very different qualities, volumes, and treatment needs will not occur.

Another important difference between Sections 816.42 and 817.42 is the definition of "disturbed areas.'' Specifically, Section 817.41 further limits the definition of this term to exclude not only areas affected by surface operations in which only diversion ditches, sedimentation ponds, or roads are located and the upstream areas are not otherwise disturbed, but also to exclude surface areas affected by underground operations, unless those areas also are affected by fills, support facilities, or other major activities incident to underground mining activities. This limitation eliminates surface areas overlying underground mine workings from treatment as "disturbed,'' in terms of the requirement of collecting all surface drainage from such areas and passing that drainage through a sedimentation pond, a series of sedimentation ponds, or a treatment facility. However, it should be noted that the exemption from the collection and treatment requirements for surface drainage from areas overlying underground mining does not apply to water which, due to subsidence or other causes, percolates from the surface down and into underground mine workings. Such drainage is required to be handled or discharged from underground workings under the second sentence of the main text of Section 817.42(a) and is subject only to the exemption of Sections 816.42(a)(1) and (2)(ii).

{15266}B. Analysis of Comments

1. Most comments received with respect to Section 817.42 were virtually identical to comments received for Section 816.42. The disposition of those comments is discussed in the preamble to Section 816.42. The few comments directed only to Section 817.42 are discussed below.

2. Section 817.42(a) has been slightly modified to provide additional clarity with respect to the criteria for sedimentation pond and treatment facility removal. More specifically, the language with regard to this subject now states that sedimentation ponds and treatment facilities for surface drainage from the disturbed area shall be maintained until the disturbed area has been restored and the vegetation requirements of Sections 817.111 817.117 are met. In addition, the criterion for pond and facility removal in the proposed rules, of meeting ambient surface water quality requirements, has been modified to require compliance with applicable State and Federal water quality standards requirements for the receiving stream. This specific change is discussed in more detail at the preamble to Section 816.42.

3. As to the criteria for removal of sedimentation ponds and treatment facilities for discharges from underground workings to surface waters, the language of the criterion for compliance with the effluent limitations has been slightly revised to require that the discharges continuously meet the effluent limitations. This modification provides additional clarity with regard to what is required and will also provide for greater assurance that the hydrologic balance will be protected over the long-term, as required by the Act.

I114. The proposed provisions of Section 817.42 relating to exemptions to the requirements for sedimentation ponds or treatment facilities have been revised to a small extent to provide for clarity. In addition, the exemption has been modified to include as a criterion, the requirement that no mixture of surface drainage and drainage from the underground mine workings takes place. This modification in the exemption criteria appeared necessary, based on the high probability for treatment of problems resulting from the mixing of waters with potentially very different quality, volumes, and thus, treatment needs. In addition, it assures that monitoring of mixed discharges, a very difficult task, is avoided.

5. A commenter stated that the requirements to collect all drainage from the disturbed area and pass this drainage through a sedimentation pond or treatment facility and to apply EPA's Effluent Limitation Guidelines for the Coal Mining Point Source Category to the discharge from this pond or facility, actually constituted applying EPA's effluent limitations for active mining areas to drainage from a "surface construction area.'' The commenter also stated that this requirement essentially amended the regulations promulgated under the Clear Water Act and, therefore, violated Section 702(a) of the Act.

The effluent limitations of Section 817.42(a)(2) are essentially identical to those of EPA for the Coal Mining Point Source Category (USEPA, 1977a). EPA's Effluent Limitations apply specifically to Coal Preparation Plants and Associated Areas, Acid or Ferruginous Mine Drainage, and Alkaline Mine Drainage. As defined in 40 CFR 434.11, General Definitions, "coal preparation plant'' means "a facility where coal is crushed, screened, sized, cleaned, dried, or otherwise prepared and loaded for transit to a consuming facility.'' The term "coal preparation plant associated areas'' is defined as the "coal preparation plant yards, immediate access roads, slurry ponds, drainage ponds, coal refuse piles, and storage piles and facilities.''

Based on these definitions, it is clear that the EPA effluent limitations are intended to include treatment of point source runoff from disturbed areas for underground mines as defined in Section 817.42(a). Since the Office is legally bound to implement regulations for water discharges which are at least as stringent as those of EPA, the application of effluent limitations of Section 817.42(a)(2) to drainage from disturbed areas, as defined in that Section, does not constitute a violation of Section 702.

SECTION 817.43-817.44 Diversions.

The authority, basis and purpose for these Sections are the same as for Sections 816.43 816.44, and, in addition, Section 516, of the Act. Comments received on these Sections were similar to those for Sections 816.43 816.44. The preamble discussion to Sections 816.43 816.44, therefore, also serves as the Office's explanation of disposition of comments to Sections 817.43 817.44.

SECTION 817.45 Hydrologic balance: Sediment control measures; and 817.46 Hydrologic balance: Sediment ponds.

These Sections are substantially identical to corresponding Sections in Part 816. The reader is referred to the appropriate portions of the preamble for Part 816 for information concerning the technical basis, alternatives considered, and statutory authority. In addition to the Sections of the Act cited in those portions of the preamble, these Sections of Part 817 are based on Section 516 of the Act. While the Office considers the effects on the hydrologic balance to be sufficiently similar in surface and underground mining to warrant substantially identical performance standards, public comment was invited on how the differences in the effects of these types of mining should appropriately be reflected in the regulations.

SECTION 817.46(a)(1)

Commenters said the requirements to construct a sedimentation pond before any disturbance to the area is unnecessary for underground mining operations. The commenters state that underground mining operations do not create situations where water would be polluted.

Sedimentation ponds are required prior to any mining disturbance of the disturbed area. Generally, underground mining activities include an exploratory drilling program, excavating and developing a bench or a working area or constructing mine portals or shafts, excavating access and haulage roads from the mine site to a power source, and construction of a tipple and coal preparation plant. In view of these surface disturbances, a sediment pond must be included to collect the sediment from these activities. Therefore, the Office has retained this Section.

The preamble discussion for Section 816.46 is incorporated herein by reference.

SECTION 817.47 Hydrologic balance: Discharge structure.

The authority for this Section is found in Sections 516(b) (7), (9), (10), and (11) of the Act, in addition to all Sections of the Act cited earlier in the preamble to Section 816.47.

{15267}The basis and purpose of this Section are the same as those offered earlier in this preamble for Section 816.47 except that the references to other Sections should be to the comparable provisions for underground mines. All public comments discussed in the portion of the preamble relating to Section 816.47 were considered and similarly disposed of, with respect to Section 817.47, because the Office believes no difference in the mining methods requires differences in discharge structure requirements between structures associated with surface mining and those associated with underground mining.

SECTION 817.48 Hydrologic balance: Acid-forming and toxic-forming materials.

(1) The authority for this Section is Section 516 of the Act, and authority cited under the preamble to Section 816.48. To account for underground development waste which is unique to underground mining activities, this Section is adopted to apply to acid-forming and toxic-forming underground development wastes and spoil. The basis and purpose for this Section are generally the same as those described for Section 816.48.

(2) The issues raised and comments received regarding this Section were similar to and discussed under the preamble to Section 816.48.

SECTION 817.49 Hydrologic balance: Permanent and temporary impoundments.

(1) The authority for this Section is found in Section 516(b) (5), (6), (7), (9), (10) and (11) of the Act, in addition to all Sections of the Act cited in the preamble discussion of Section 816.49. The basis and purposes of this Section are the same as for Section 816.49 of this Subchapter. All public comments discussed in the portion of the preamble relating to Section 816.49 were considered, and similarly disposed of with respect to Section 817.49 because there is no basis for a difference in the permanent and temporary impoundment requirements for structures associated with surface mining or the surface effects of underground mining.

In addition to the comments discussed in the Preamble portion relating to Section 816.49, one commenter recommended that Section 817.49(a) be eliminated from the final rules because the major concern with permanent impoundments focused exclusively on those impoundments left after surface mining operations. This was not accepted and the requirements covering any permanent impoundments associated with underground mining operations were retained in the final rules. It is anticipated that there will be cases when impoundments are constructed to provide a water source for underground mining operations and some of these impoundments may be left as permanent structures. If this occurs, these regulations will apply to the structures, whether or not the regulations of the Corps of Engineers or Environmental Protection Agency apply.

SECTION 817.50 Hydrologic balance Ground water protection.

1. Section 817.50 provides the protection of the mining area's hydrologic balance by requiring that mining operations be conducted so as to preclude uncontrolled discharge of mine water. Uncontrolled discharges (mine drainage) have been a primary cause of adverse impacts upon water quality and ecology in the past (Biesecker and George, 1966, pp. 5 8; Broley, 1954, 3 pp.; Grubb and Ryder, 1972, pp. 16 58; Sidio and Mackenthun, 1963, pp. 16 21; Turner, 1958, pp. 45 46; Warner, 1973, p. 227).

However, this problem can be controlled in underground mines through the proper location, design, construction, utilization, and sealing of drifts, adits, and slopes (EPA, 1973b, pp. 30 34). Use of some of these methods to control drainage during the active mining phase is to be supplemented with collection and conveyance of drainage to treatment facilities as necessary to comply with applicable standards and limitations prior to discharge to receiving streams.

The outright prohibition on gravity discharges at Section 817.50(c) from certain drift mines is required under Section 516(b)(12) of the Act.

2. The Office considered requiring all drift mines which are opened after the effective date of this Part to comply with Section 817.50(c), rather than making the requirements applicable only to mines opening after approval of the State or Federal program. The Office believes that until a regulatory authority is identified and approved by the Secretary and empowered to administer a regulatory program, it will be unfair to the operator to make this provision apply. Determination of whether a coal seam involved is "acid-producing'' or "iron-producing'' would not have been made until a permit application was reviewed by the regulatory authority.

3. A few commenters suggested that for drift mines which lie above drainage, that solid coal barriers of 50 feet plus one foot of potential hydrostatic head at all points around and above the workings be required. The Office recognizes that certain States require such standards as efforts to control acid drainage. However, the Office rejected this proposal, because such site-specific techniques are not appropriately applicable nationwide, particularly in the west where underground mining may not produce acid drainage. The provisions of Sections 817.41, 817.42, 817.48, 817.50, and 817.55 aree extensive enough in scope to adequately cover the drainage situations raised by the commenters. Of course, Section 516(b)(12) of the Act and Section 817.50(c) specifically prohibit a gravity discharge of water from new drift mines.

SECTION 817.51 Underground mining: Protection of ground water recharge capacity.

As explained in the preamble to the proposed rules (43 FR 41780), the Office did not believe it appropriate to promulgate a regulation concerning restoration of recharge capacity with respect to underground mining activities. However, comments were solicited as to whether any requirements may be needed to protect the recharge capacity of water bearing formations from underground mining activities. One comment was received on this point in support of deleting this Section. The Section has not been included in the final rules.

SECTION 817.52 Hydrologic balance: Surface and ground water monitoring.

(1) Authority for this Section is derived from the same Sections of the Act as for Section 816.52 and from Section 516 of the Act.

(2) Most comments and issues relating to this Section were similar to those raised as to Section 816.52 and are discussed in the Preamble to that Section.

(3) Several commenters questioned whether quantity monitoring of surface discharges from underground mine permit areas following reclamation is necessary, in view of the small area disturbed relative to surface mining operations. The Office concurs with the commenters that, where the surface disturbed areas is relatively small the impact to the hydrologic balance following mining should be negligible. Where this is the case and the disturbed areas have been regraded and stabilized, it makes little sense to require the monitoring of surface flows (quantity) even though quality would need to be continuously monitored. However, no change in wording was deemed necessary, as Section 816.52(b)(2) provides for sufficient flexibility to the regulatory authority to limit or reduce water quantity monitoring in the circumstances suggested.

SECTION 817.53 Hydrologic balance: Transfer of wells.

Authority for this Section is Section 516 of the Act and those provisions cited in the preamble to Section 816.53. That portion of the preamble also explains the general basis and purpose of this Section. All comments received and issues raised were similar to those comments and issues on Section 816.53 and are discussed in the preamble to that Section.

SECTION 817.54 Hydrologic balance: Water rights and replacement.

1. Authority for this Section is the same as that for Section 816.54, and in addition Section 516 of the Act. Most comments and issues raised as to this Section were the same as those raised as to Section 816.54 and are discussed in the preamble to that Section.

2. Several comments questioned whether Section 717 of the Act authorizes Section 817.54 as a regulation of the effects of underground mining on underground water. Since it was the intent of Congress for this Act to apply to underground mining as well as to surface mining, the Office has decided not to delete the Section.

Section 515(b)(10) of the Act requires surface mining to "minimize the disturbances to the prevailing hydrologic balance at the mine site and in associated offsite areas and to the quality and quantity of water in surface and ground water systems. . . .'' Section 508(a)(13) requires mining and reclamation plans, in general, to provide for protection of surface and ground waters, including "rights of present users to such water.'' Sections 516(b)(10) and 516(d) of the Act incorporate provisions of Section 508 and 515, by referencing regulation of underground mining activities and allowing for any "distinct differences'' in underground mining. There are no "distinct differences'' justifying elimination of Section 817.54.

If anything, underground mining can have a more severe impact on users of surface and ground water than surface mining activities, as is evident from the technical literature cited in the preamble to the proposed rules, 43 FR 41780 (discussion of Sections 817.41 817.57) and 41784 41785 (GAI, 1977, pp. 22 23; Dunrud, 1976, p. 61). Therefore, the Office interprets Section 717 of the Act to require establishment of this performance standard since underground mining can have such impacts on users of water.

3. A commenter felt that the Section should be changed to explicitly provide that the operator would have to replace the water supplies of permittees for grazing on public lands, if the mining operation diminished those supplies. The Office rejected this proposal as it believes, first, that permittees' water supplies for grazing would be included under ". . . water supply of an owner of interest,'' and, second, is specifically covered under provisions of Section 715 of the Act, and 30 CFR 742.

SECTION 817.55 Hydrologic balance: Discharge of water into an underground mine.

1. Section 817.55 provides protection of the hydrologic balance of a mining area by restricting the discharge or diversion of water from surface mines or from one underground mine area into other underground mine workings. The basic authority for this Section is the same as for Section 816.55 and, in addition, Section 516 of the Act. Section 817.55(d) was inserted to recognize the possible transfer of water from one underground mine area to another. Co-mingling of surface water and ground water or from two or more sources of ground water may unexpectedly occur as a result of a strip mine intercepting an underground mine or waters from one underground mine breaking through into another (USEPA, 1973(b), p. 207; Commonwealth of Pennsylvania v. Harmar Coal Co., PA Sup. Ct. (1974). For example, the elevation of shallow ground water in a southeastern Ohio surface mine area dropped about 100 feet as a result of water breaking into a dry mined out area below (Bureau of Mines, 1977b, pp. 50 51).

2. The issues raised by comments on Section 817.55 regarding (1) the need for approval by the Mine Safety and Health Administration; and (2) the need for an exception for pH effluent limitations in the discharge into underground workings, are identical to issues raised under Section 816.55, and the same modifications have been made to both Sections.

3. A commenter questioned the meaning of the opening paragraph for Section 817.55, as to whether it dealt with underground workings in the same mine or others. The commenter felt that the "blanket approach'' was not applicable to the entire underground mining industry. The Office recognized this language problem and, therefore, specified "surface'' mines in the final rule. The Office's intent is discussed adequately in the preamble to Section 816.55 it excludes diversions and discharges from either surface and underground mines into other underground mines, unless certain pollution abatement criteria are demonstrated to the satisfaction of the regulatory authority.

SECTION 817.56 Hydrologic balance: Postmining rehabilitation of sedimentation ponds, diversions, impoundments, and treatment facilities.

The authority for this Section is found in Sections 516(b)(4), (5), (6), (7), (9), (10), and (11) of the Act in addition to all Sections of the Act cited in the preamble discussion of Section 816.56.

The basis and purpose of this Section are the same as for Section 816.56 of this Subchapter. All public comments discussed in the portion of the preamble relating to Section 816.56 were considered, and similarly disposed of, with respect to Section 817.56, because the Office believes there is no difference between surface and underground mining which would justify varying rehabilitation requirements between structures associated with surface mining and underground mining.

SECTION 817.57 Hydrologic balance: Stream buffer zones.

1. Authority for this Section is the same as for Section 816.57 and, in addition, Section 516 of the Act. Most comments and issues raised relating to this Section were similar to those raised as to Section 816.57 and have been discussed in the preamble to Section 816.57.

2. A few commenters questioned the applicability of the buffer zone provisions to underground mines. One alternative considered was deletion of this Section on the basis of comments that underground mine workings do not affect surface streams. A second alternative would have left the provision as proposed, because both surface operations and underground mine workings located too close to streams may cause problems. A third alternative considered was to modify the provision to recognize any differences between surface and underground mines as to their effects on streams and the need for buffer zone markers in the underground workings.

The Office rejected the first two alternatives in favor of the third. Biologically significant streams need protection from surface disturbances of underground mines caused by coal dust and sediment production along haul roads, the discharge of mineralized water from processing plants or underground sumps, and the disruption of overland-runoff patterns caused by ditching (Karr and Schlosser, 1977, pp. 16-29; Grim and Hill, 1974, p. 102; Weigle, 1965, 23 pp.). Because of the adverse environmental effects to streams which may be generated by surface operations and facilities, the Office decided to require the use of stream buffer zones under Section 516 of the Act. The Office believes that Sections 817.121 817.126 (subsidence control) adequately protect surface streams from adverse effects of underground mine workings themselves.

SECTION 817.59 Coal recovery.

This Section addresses two persistent problems of coal mining: (1) The loss of coal resources when mining does not recover all the coal at a particular mining site; and (2) Recurrent environmental degradation when land is reopened for mining to recover the remaining coal.

{15269}The authority for this Section is found in Sections 102, 201, 501, 503, 504, 510, and 516 of the Act.

Discussion of specific language and alternative language to require fixed percentages of coal recovery are in the preamble discussion of Section 816.59 to which the reader is referred for a discussion of issues relevant to this Section.

One comment was received suggesting that specific percentages of coal recovery be required. This comment was rejected for the reasons explained in the preamble to Section 816.59.

One commenter suggested that OSM should not promulgate a standard for coal recovery of underground mining, on the grounds that the Act did not authorize Federal coal recovery standards for deep mines, citing Section 517(a) of the Act limiting inspections to strip mines. OSM has rejected this suggestion on the basis that Section 515(b)(1) itself, and as applied through Section 516(b)(10), requires coal recovery standards for deep mines. Moreover, OSM feels that Section 517(a) of the Act authorizes inspections of underground mines. Section 517(a) authorizes inspection of "surface coal mining and reclamation operations.'' This phrase is defined by Section 701(28) of the Act and Section 700.5 of these regulations to include the surface effects of underground mining. The amount of coal recovered has an effect on the surface in that maximum recovery can preclude the need to redisturb the surface at a future date, a primary objective of this Section of the regulations. Maximum recovery from an underground mine may be a smaller percentage of the total coal than would be recovered using surface mining methods if such methods were feasible for the specific site.

It is understood that the operator must strike a balance between this requirement to maximize coal recovery and the requirements of Sections 817.121 .126 dealing with subsidence control. Both the coal recovery plan and subsidence damage control plan must be approved by the regulatory authority.

SECTIONS 817.61-817.68 Use of explosives.

These Sections are promulgated under the authority of Sections 102, 201, 501, 503, 504, 507, 510, 515, 516, and 719 of the Act. Most of the provisions of these regulations are substantially identical to the blasting performance standards regulations for surface mining activities (Sections 816.61-816.68). To that extent, the reader is referred to the appropriate portions of the preamble for Part 816, which contains the rationale, in general, for parts of Sections 817.61-817.68 which are not specifically discussed in the preamble to Part 817.

SECTION 817.61 Use of explosives: General requirements.

Numerous comments were received which pertained specifically to Section 817.61. As a result of these comments, the following alternatives were considered and alternatives two, three and four were adopted by the Office.

1. Retain the wording of Section 817.61(a) as proposed.

I112. Revise Section 817.61 to restrict Section 817.61 817.68 to only surface blasting activities incident to underground mining, including construction of initial rounds of slopes and shafts. As a result of such an addition, portions of Section 817.65(a) of the proposed regulations would become unnecessary.

3. Delete reference in Section 817.61(a) to Sections 816.61 816.68.

4. Delete Section 817.61 of the proposed regulations, which required a blasting schedule for surface blasting incident to underground mining.

Alternative 2_ Numerous commenters have pointed out an obvious ambiguity in the proposed blasting regulations for underground mining. Although proposed Section 817.65(a) stated that the provisions of that Section applied only to blasting conducted on the surface, that distinction was not made for the rest of Sections 817.61 817.68. Adoption of alternative two clarified the Office's intent not to regulate blasting performed underground, because this activity is adequately controlled by MSHA. By adding Section 817.61(a) to the final rules, proposed Section 817.65(a) was made unnecessary and was changed in the final rules.

Alternative 3 _In response to comments that underground mining activities should not be subject to all requirements of Sections 816.61 816.68, the Office revised Section 817.61(a) so that the final rules require underground mining activities to comply only with Sections 817.61 817.68, which have been appropriately tailored solely for those activities.

Alternative 4 _Several commenters objected to the requirement of the proposed rules for a blasting schedule for surface blasting incident to underground mining. The Office agrees because it was not the intent of Congress to require a blasting schedule for this type of blasting. Section 817.65(a), requiring a 24 hour notification for blasts of this type, is adequate protection for the public, given the limited frequency and duration of surface blasting associated with underground mining activities.

One commenter pointed out that MSHA's proposed rule, Section 77.1308(i), will allow blasting at night in slopes and shafts at underground operations except for the initial rounds on the surface. The Office finds no conflict with MSHA's proposed rule, as the Office does not regulate blasting under Part 817 inside underground mine workings. Initial rounds of slopes and shafts have been provided for in final Section 817.61(a) which regulates surface blasting for underground mining.

SECTION 817.62 Use of explosives: Preblasting survey.

A few commenters recommended limiting the area in which preblast surveys are required for surface blasting associated with underground mining to a one-half mile radius from the blasting activities, as provided for in Section 515(b)(15) of the Act. The Office accepted these comments, because there was no apparent basis to expand the area for mandatory pre-blast surveys from surface mining (one-half mile) for underground mines (any portion of the mine).

SECTION 817.65 Use of explosives: Surface blasting requirements.

(1) Several comments were received concerning the 24 hour notice required for surface blasting in support of underground mining in the proposed rules. As a result of these comments the following alternatives were considered and alternative 2 was adopted.

1. Retain the wording as published in the proposed regulations.

2. Modify Section 817.65(b) by inserting "approximately'' in front of "24 hours'' and inserting "surface'' in front of "blasting event.''

3. Change the Section to require a notice at least 10 days, but not more than 20 days, prior to blasting.

4. Delete the Section.

Alternative 2.

One commenter objected that the notice of blasting was required to be given exactly 24 hours prior to blasting. As this would not be necessary or practical if there are a large number of surrounding residents to be notified, the word "approximately'' has been added to qualify the advance notice requirement.

Alternative 4.

The same commenter also questioned the Office's authority to promulgate blasting regulations for underground mines, because blasting is not one of the subjects listed in Section 516(d) of the Act. However, Section 516(b)(10) of the Act makes all of the performance standards of Section 515 of the Act applicable to "other surface impacts'' not specified in Section 516(b) of the Act, thereby incorporating, by reference, Section 515(b)(15) of the Act. Further, Section 516(d) of the Act makes the permit application requirements of Title V of the Act applicable to underground mining. Under the permit application requirements at Section 507(g) of the Act, there is a requirement that the applicant establish how the blasting provision of 515(b)(15) of the Act will be met. Therefore, the Office does have the authority to promulgate rules for surface blasting at underground coal mines that are in accordance with Section 515(b)(15), as modified so as to accommodate any distinct difference between surface and underground coal mining.

{15270}Surface blasting associated with underground coal mining, as compared to surface mines, commonly involves a lesser quantity of explosives and is not of such a continuing nature as for surface mining activities, because smaller surface areas of overburden removal are involved. However, underground mining activities do involve substantial blasting for road or facilities construction, "facing-up'' operations for installation of adits, and initial blasts for slopes and shafts. The environmental impact of these generally smaller blasts, conducted for a shorter time period, is less severe than the legislative history indicates for surface mining blasts. Therefore, the provisions of Section 515(b)(15)(A) of the Act required modification as applied to underground mining activities. In the Office's judgment, a notification of blasting approximately 24 hours in advance of the blast will provide adequate notification for the infrequent type of blasting involved.

Alternative 3.One commenter recommended that notifying residents within 1/2 mile at least 10 days, but not more than 20 days, prior to any blasting event be required only for "facing-up operations,'' on the theory that this modification would conform Part 817 to proposed Section 816.64(a). Section 816.64, however, requires publishing a blasting schedule in the local newspaper for all types of blasting. Because there was no basis shown by the commenter to distinguish among the types of blasting in surface work in underground min ing, the Office rejected the comment.

(2) 817.65(d).

One commenter requested clarification as to which underground mining activities require maintenance of signs under Section 817.11(f). In response, the Office has clarified the wording of this Section to specify persons who conduct surface blasting incident to underground mining. The commenter correctly noted that, as proposed Section 817.65(d) would have required any person conducting underground mining activities to comply with all of the provisions of Section 817.11(f).

SECTION 817.68 1. Use of explosives: Record of blasting operations.

1. A few comments specifically directed to the blasting record requirements of proposed Section 817.68 were received. Some commenters felt that it was unclear whether Section 817.68 applied to blasts fired underground. However, the wording of Section 817.61(a) in the final rules makes it clear that only blasts fired on the surface and initial rounds in construction of shafts and adits are subject to the provisions of Section 817.68.

(2). One commenter suggested that a threshold size of blast be specified below which a blasting record is not required. The Office rejected this suggestion. As is discussed in detail in the preamble to Section 816.61, blasting involving the use of more than five pounds of explosives needs to be closely regulated, because of the potential for damage and harm to the public. In order that the regulatory authority can properly evaluate whether the requirements of the regulations specifying procedures and standards for blasting of over five pounds are being complied with, it is necessary that the identity, location, duration, types, and amounts of explosives used be recorded. These items will establish whether the operator, is, in fact, blasting with more or less than five pounds. Furthermore, the number and types of holes and description of delays used are appropriate means for cross-checking the claims of the operator in the total weight of explosives used per blast. Finally, other data required by Section 816.68 are useful to establish a historical data base by which the operator can predict how to conduct blasting over time.

SECTIONS 817.71-817.74 Disposal of underground development waste and excess spoil.

Authority for these Sections is found in Sections 102, 201, 501, 503, 507, 508, 510, 515, and 516 of the Act.

The basis and purpose of these Sections are the same as for Sections 816.71 816.74 of this Subchapter. All public comments discussed in the portion of the preamble relating to Sections 816.71 816.74 were considered and similarly disposed of with respect to Sections 817.71 817.74, because the Office believes that the differences between underground and surface mining do not justify differences in the coal development waste and excess spoil disposal requirements between structures associated with surface mining and those associated with underground mining. In effect, the Office believes that disposal of underground development wastes pursuant to these Sections will provide, and is necessary to insure, the same level of protection for the environment and public health and safety as is required for the disposal of excess spoil associated with surface mining.

The reader is referred to Sections 816.71 816.74 for a discussion of comments and issues relative to Sections 817.71 817.74.

SECTIONS 817.81-89 Coal processing waste banks and disposal of non-coal waste.

Authority for these Sections is found in Sections 102, 201, 501, 503, 504, 507, 508, 510, 515, and 517 of the Act.

The basis and purpose of these Sections are the same as for Sections 816.81 816.89 of this Subchapter. All public comments discussed in the portion of the preamble relating to Sections 816.81 816.89 were considered and similarly disposed of with respect to Sections 817.81 817.89, because OSM believes that the differences between surface and underground mining do not justify differences in the waste disposal requirements between structures associated with surface mining and those associated with underground mining.

The reader is referred to Sections 816.81 816.89 of the preamble for a discussion of comments and issues relative to Sections 817.81 817.89.

SECTIONS 817.91-817.93 Coal processing waste: Dams and embankments.

The authority for these Sections is found in Section 516 of the Act, in addition to Sections of the Act cited in the preamble discussion of Sections 816.91 816.93.

The basis and purpose of these Sections are the same as for Sections 816.91 816.93 of this Subchapter. All public comments discussed in the preamble relating to Sections 816.91 816.93 were considered and similarly disposed of, with respect to Sections 817.91 817.93, because OSM believes that the differences between surface and underground mining do not justify differences in the coal processing waste dam requirements between structures associated with surface mining and those associated with underground mining.

SECTION 817.95 Air resources protection.

The basis and purpose of this Section are the same as for Section 816.95 of this Subchapter. All public comments discussed in the preamble to Section 816.95 were considered and similarly disposed of with respect to Section 817.95. The statutory authority for this Section is the same as that for 816.95 with the addition of Section 516 of the Act. Consideration of whether underground mines should be regulated differently than surface mines with respect to air pollution control is discussed in the preamble to 30 CFR 784.26. Fugitive dust control techniques are the same whether the dust originates from surface or underground mines and therefore Section 817.95 is identical to Section 816.95.

SECTION 817.97 Protection of fish, wildlife, and related environmental values.

This Section is essentially identical to the corresponding Section of Part 816. Refer to the preamble to Section 816.97 for information concerning the technical basis, alternatives considered, statutory authority and responses to comments addressing that Section. The discussion in the preamble supporting Section 816.97 also applies to Section 817.97. In addition to those authorities listed in preamble to Section 816.97, this Section is also supported by Section 516 of the Act.

The only issue raised by commenters in this Section which differed from Section 816.97 centered around the geographic area to be studied and which plans would be required for purposes of fish and wildlife resources protection. For a discussion of those differences see Sections of the preamble dealing with area to be studied, and fish and wildlife plans, Sections 779.20(a), 780.16(a)(1), 783.20(a), and 784.21(a)(1). Once the geographic area of study has been established and the fish and wildlife plan approved, the performance standards are identical.

No other differences in requirements of this Section and Section 816.97 were identified.

SECTION 817.99 Slides and other damage.

This proposed Section is substantially identical to the corresponding Section of Part 816. The reader is referred to the appropriate portions of the preamble for Part 816 for information concerning this Section. In addition to the Sections of the Act cited in those portions of the preamble, this Section is based on Section 516 of the Act. The Office considers the risks of slides to be sufficiently similar in surface and underground mining to warrant identical performance standards.

SECTION 817.100 Contemporaneous reclamation.

The authority for this Section is found in Sections 102, 201, 501, 503, 509, 510, 515, and 516 of the Act.

The basis and purpose of this Section are the same as Section 816.100 of this Subchapter. All public comments discussed in the portion of the preamble relating to Section 816.100 were considered, and similarly disposed of, with respect to Section 817.100. The Office believes that the differences between surface and underground mining do not justify differences in contemporaneous reclamation requirements between surface and underground operations affecting the surface. The reader is referred to Section 816.100 for a discussion of issues relative to Section 817.100.

SECTIONS 817.101-817.103 Backfilling and grading.

1. Sections 817.101 817.102 are regulations for backfilling and grading of areas disturbed by underground coal mining activities. Disturbed areas are to be reshaped to approximate original contour in a manner that minimizes erosion and water pollution and prevents slides. A level of surface productivity equal to that attained prior to mining and under proper management is to be achieved on this restored area. Authority for these Sections is found in the Act in Sections 102, 201, 501, 503, 504, and 516.

2. In Section 817.102 and 103, several commenters requested a change which would allow final graded slopes to be consistent with an approved post mining use plan rather than the stipulated pre-mining slopes or lesser slopes approved by the regulatory authority, where mining activities are reaffecting previously mined lands. Section 515(b)(3) of the Act clearly states ". . . to restore the approximate original countour of the land with all high walls, spoil piles and depressions eliminated.'' Section 516(b)(10) of the Act calls for surface disturbance of underground mining activities to operate in accordance with the standards established under Section 515 of the Act. Section 817.102(a) allows for modification of this requirement where mining activities are reaffecting previously mined lands that have not been restored to the standards of the Section. Since the commenters provided no further technical justification the language for this Section is retained.

3. Some commenters requested that Section 817.102(a)(2) be revised to include slopes which exeed 50%, as in Section 817.102(b)(3). Section 817.102(b)(3) refers only to terrace cut slopes. Spoil slopes are to be graded to the most moderate slope possible. This is intended to avoid long slopes with over a 50% gradient. Grim and Hill, pp. 149 197, Section IX. The language change has been rejected.

SECTION 817.103(a)(1) and (a)(2) Toxic material.

Comments were received on Section 817.103 (a)(1) and (a)(2) requesting that an exemption be allowed from four-foot cover requirements over acid or toxic producing material. These Sections are substantially identical to the corresponding Sections of Part 816. The reader is referred to the preamble discussion for Sections 816.103(a)(1) and (a)(2) for information concerning the technical basis, and alternatives considered for Part 817, including the disposition of similar comments. In addition to Sections of the Act cited in those portions of Part 816 in the preamble, these Sections are based on Section 516 of the Act.

817.103(b).

Comments were also substantially the same as those received on the corresponding Sections of Part 816. The reader is directed to the preamble discussion for Part 816 for the disposition of comments received on this Section. In addition to the Sections cited in the preamble to Part 816, Section 516 of the Act authorizes these Sections.

SECTION 817.106 Regrading or stabilizing of rills and gullies.

This Section is substantially identical to Section 816.106. The reader is referred to Section 816.106 for information concerning the technical basis, alternatives considered, and statutory authority for the Section. In addition to the Sections of the Act cited in these portions of the preamble, this Section is based on Section 516 of the Act. The Office considers the need for correction of gullying to be sufficiently similar in surface and underground mining to warrant substantially identical performance standards.

SECTION 817.111-817.117 Revegetation.

1. These regulations are intended to ensure establishment of a diverse, permanent, self-generating vegetation capable of plant succession and at least equal in extent of cover to the natural vegetative cover. It will be necessary that underground mining operations stabilize and revegetate all lands affected by their operations.

These Sections are issued under the authority of Sections 102, 201, 501, 503, 504, 510, and 516 of the Act.

2. In response to public comments, these regulations differ from those for surface mining and those differences are discussed here. For additional discussion on the development of these regulations, the reader is referred to Part 816 for those Sections regulating activities that warrant substantially the same regulations.

3. Section 817.111 sets forth the general requirements for revegetating surface areas affected by underground mining operations. Persons conducting underground mining activities are required to establish a diverse and permanent vegetative cover on all areas disturbed by surface operations. The revegetation shall be in accordance with the plan and carried out in a manner that encourages prompt vegetative cover and productivity levels compatible with the approved post-mining land use.

Several commenters expressed concern that the revegetation requirements of Section 516(b)(6) of the Act were substantially different for underground mining as compared to surface mining and they argued that this difference warranted regulations that were substantially different. Since Section 516(b)(6) does differ from Section 515(b) (19) and (20), primarily by not requiring native vegetation of the same seasonal variety when revegetating areas disturbed by underground mining operations, the appropriate changes were made in Sections 817.111 and 817.112 to reflect that difference.

{15272}4. Some commenters contended that the Act required greater recognition of ecological principles and biological community dynamics. This suggestion was accepted and the language changed to require vegetation capable of self-regeneration and plant succession, in accordance with Section 516(b)(6) of the Act. For the same reason the proposed requirement of "the same seasonal variety'' was deleted and changes were made to specifically list the vegetative requirements of the Act.

As mentioned above, Section 817.112 was changed to reflect the different vegetative species requirements of Section 515(b)(6) as compared to the requirements of Section 515(b) (19) and (20).

The Office believes that Sections 817.113 through 817.117 should be substantially identical to the corresponding Sections of Part 816. The reader is referred to the appropriate part of the preamble for Part 816 for information and discussion of the alternatives considered for these Sections.

SECTIONS 817.121-817.126 Subsidence control.

The regulations on subsidence are intended to ensure that underground mining is conducted so as to protect the health and safety of the public, minimize damage to the environment, and protect the rights of landowners. The subsidence control regulations will reduce subsidence-caused material damage to the land surface by improving mining methods, as well as by maintaining the value and potential of the land.

Authority for these Sections is found in Sections 102, 201, 501, 503, 510, 516, 517, and 522 of the Act.

Technical literature relied upon in writing these regulations includes:

1. "Acid Mine Drainage and Subsidence-Health and Ecological Effects of Increased Coal Utilization,'' Hill, Ronald D. and Bates, Edward R., Resource Extraction and Handling Division, Industrial Environmental Research Laboratory-Cincinnati, U.S. Environmental Protection Agency, Cincinnati, Ohio 45278, 1977.

2. "A Comprehensive Program for Dealing with Mine Subsidence,'' ARC Report 73 163 1559, prepared by Michael Baker, Jr., Inc., Beaver, Pennsylvania, and the Institute of State and Regional Affairs. The Pennsylvania State University, Middletown, Pennsylvania, for the Appalachian Regional Commission, Washington, D.C., and the Pennsylvania Department of Environmental Resources, Harrisburg, Pennsylvania, 1976, Chapter 6, pages 49 51.

3. "Subsidence Engineers Handbook,'' National Coal Board (British), Production Department, London, 1966, 1974.

4. Architectural Measures to Minimize Subsidence Damage, ARC Report 73 111 2551, prepared by Michael Baker, Jr., Inc., Beaver, Pennsylvania, for the Appalachian Regional Commission, Washington, D.C., and the Pennsylvania Department of Environmental Resources, Harrisburg, Pennsylvania, 1974.

5. "Overview of Subsidence Potential in Pennsylvania Coal Fields,'' ARC Report 73 111 2552, prepared by HRB-Singer, Inc., State College, Pennsylvania, for the Appalachian Region Commission, Washington, D.C., and the Pennsylvania Department of Environmental Resources, Harrisburg, Pennsylvania, 1975.

6. Gray, R. E., Gamble, J. C., McLaren, R. J., and Rodgers, D. J., "State of the Art Subsidence Control,'' ARC Report 73 111 2559 prepared by General Analytics, Inc., ("GAI'') Monroeville, Pennsylvania, for the Appalachian Regional Commission, Washington, D.C., and the Department of Environmental Resources, Harrisburg, Pennsylvania, 1974, part 2.

7. "Use of Photo Interpretation and Geological Data in the Identification of Surface Damage and Subsidence,'' ARC Report 73 111 2554, prepared by Earth Satellite Corporation, Washington, D.C., for the Appalachian Regional Commission, Washington, D.C., and the Pennsylvania Department of Environmental Resources, Harrisburg, Pennsylvania, 1975, pages 35 37.

8. "Local and State Regulatory Powers Dealing with Land Use and Construction in Subsidence Prone Areas,'' ARC Report 73 163 2557, prepared by Mullin L. Lonergan Associates, Inc., Philadelphia, Pennsylvania for the Appalachian Regional Commission, Washington, D.C., and the Pennsylvania Department of Environmental Resources, Harrisburg, Pennsylvania, 1975, Appendix A.

9. U.S. Congress, 95th, 1st session, House Rept. 95 128, 1977, Surface Mining Control and Reclamation Act of 1977, Report of the Committee on Interior and Insular Affairs, House of Representatives, to accompany H.R. 2, p. 126 10. U.S. Department of Interior, 1976, Final Environmental Impact Statement on Surface Subsidence Control in Mining Regions; U.S. Bureau of Mines FES 76 58, 90 p.

10. U.S. Department of Interior, 1976, Final Environmental Impact Statement on Surface Subsidence Control in Mining Regions: U.S. Bureau of Mines FES 76 58, 90 p.

11. National Coal Board, 1963, Principles of subsidence engineering: Production Department Information Bull 63/240, 21 p., London, UK.

12. Dunrud, C. R. 1976. Some engineering geologic factors controlling coal mine subsidence in Utah and Colorado: U.S. Geological Survey Professional Paper 969, 39 p.

13. Brauner, G., 1973, Subsidence due to underground mining: I. theory and practices in predicting surface deformation: U.S. Bureau of Mines Info-Circ 8571, 55 p.

14. Battelle Columbus Laboratories, 1975, A systems approach to underground mining: Phase I problem analysis and research recommendations, 282 p.

15. Campbell, J. A. L., Petrovic, L. J. Mallis, W. J., and Schulties, C. W., 1975, How to predict coal mine roof conditions before mining: Mining Engineering, October, pp. 37 40.

16. Vandale, A. E., 1967, Subsidence_a real or imaginary problem: Mining Engineering, September pp. 86 88.

17. Horn, G. H., 1977, Memorandum on subsidence requirements_coal: U.S. Geological Survey memo to mining supervisors.

18. Allen, A. S., 1976, Basic questions concerning coal mine subsidence in the United States: Assn. Engr. Geologists Meeting, April 1976, 19 p.

19. Amuedo and Ivey, "Ground Subsidence and Land use considerations over coal mines in the Boulder-Weld Coal Field, Colorado'', Amuedo and Ivey Geological Consultants, 1975.

20. "Study and Analysis of Surface Subsidence over the mined Pittsburgh coal bed,'' report prepared for U.S. Department of Interior, Bureau of Mines under contract No. J0366047 by GAI Consultants Inc. Monroeville, Pennsylvania, July 1977.

21. Wardell, Kenneth, "Ground Subsidence and Control'', Mining Congress Journal, January, 1969, pp. 36 43.

22. Kratzsch, Helmut, "Reduced Subsidence by Planned Extraction'', Bergbau-Archiu (Essen), Vol. 25, No. 5, December 1964, pp. 15 21.

23. Panek, Louis A., "Methods and Equipment for Measuring Subsidence,'' Third Symposium on Salt, the Northern Ohio Geological Society, Inc., Cleveland, Ohio, 1966.

24. Voight, Barry and Pariseau, William, "State of Predictive Art in Subsidence Engineering,'' Journal of the Soil Mechanics and Foundation Division, Proceedings of the American Society of Civil Engineers, March, 1970, pp. 721 740.

25. Legget, R. F., "Duisburg Harbour Lowered by Controlled coal Mining,'' Canadian Geotechnical Journal, 9, 374, 1972, pp. 874 3832.

26. Brauner, Gerhard, "Subsidence Due to Underground Mining 2. Ground Movements and Mining Damage,'' U.S. Bureau of Mines Information Circular 8572, 1973

{15273}27. "Bituminous Mine Subsidence and Land Conservation Act of 1966,'' Commonwealth of Pennsylvania (Department of Environmental Resources), Harrisburg, Pa.

28. Curtis, S. E., Talk Presented at the Roof Control Committee Meeting of the American Mining Congress Pittsburgh, Pa., September 18, 1968.

29. Dunrud, C. R., and Osterwald, F. W., 1978, Effects of coal mine subsidence in the western Powder River Basin, Wyoming: U.S. Geol. Survey Open-File Report 78 473, 71 p.

30. Osterwald, F. W., 1961, Deformation and stress around coal mine workings in Sunnyside No. 1 mine, Utah: U.S. Geol. Survey Prof. Paper 424 C, p. C348 353.

31. USGS, 1962, USGS relates geologic structures to bumps and deformation in coal mine workings: Mining Engineering, v. 14, no. 4, p. 63 68.

Section 516(b)(1) of the Act requires undergound mine operators to adopt measures consistent with known technology in order to prevent subsidence-caused material damage to the extent technologically and economically feasible. Room amd pillar mining is not prohibited. If no subsidence control measures are adopted, there is the possibility of material damage to private dwellings (National Coal Board, p. 46, 1974), gas and electrical utilities (GAI, 1977), sewers (National Coal Board, pp. 57 58, 1974) and water resources such as springs and farmland (Dunrud and Osterwald, p. 59, 1978).

In order to evaluate best the likelihood of material damage, it is desirable to conduct underground mining in a manner such that the time and extent of subsidence can be predicted in as precise a manner as possible. Damage caused by subsidence can occur many decades after mining (Dunrud and Osterwald, p. 6, 1978) because of long-term instability of mine pillars, indicating the need for proper subsidence control measures in order to "maximize mine stability.'' Subsidence effects can also extend off the mining site (National Coal Board, p. 16, 1974; Baker, pp. 40 42, 1974; HRB-Singer, p. 25; and Grey, et al, p. II 26, 1974) at angles (measured horizontally from the edge of mining) varying from 35 degrees to 70 degrees (Brauner, Vol. 1, p. 9, 1973) and may result in damage to structures not situated directly over the mining site.

Determination of on- and off-site subsidence potential requires consideration of coal thickness mined, mining geometry and dimensions, and the nature of overlying and underlying strata (National Coal Board, pp. 8 24, 1974; Brauner, Vol. 1, p. 6, 1973; GAI 1977; and Voight, pp. 723 30, 1970). Determination of the potential effects of subsidence on structures and other facilities requires consideration of subsidence-caused ground strains and deflections and the nature of the structures themselves (National Coal Board, p. 24, 1974; Brauner, Vol. II, p. 2, 1973; Voight, p. 740, 1970; and Pennsylvania DER, p. 59, 1966). Therefore, adequate definition of the time and extent of subsidence and the prevention of material damage require careful consideration of the value and use of the land surface, detailed knowledge of the geologic and mining characteristics of the site (Osterwald, p. C 349 53, 1961, p. 64, 1962), and proper attention to geotechnical design principles.

Technology is available to minimize and reduce subsidence-caused material damage for both the standard room and pillar mining method and other methods, such as longwall mining, which are currently used in this country. Excellent protection of sensitive surface features such as urbanized areas and important historic and cultural features or farmland can be achieved by refraining from mining underneath and adjacent to these features as, for example, provided in Section 817.57 with respect to certain streams. Similar protection is currently required in Pennsylvania for protected structures consisting of public buildings, dwellings, and cemeteries, when the mine operator cannot post bond or does not have an approved financial statement. (Penn. DER, p. 60, 1966). Similar protection is required by MSHA for oil and gas wells.

Control of surface subsidence with respect to other structures can be achieved through proper design of mining operations to leave supporting coal in place, when using the room and pillar method (Curtis, pp. 4 6, 1968). Protection of the surface can also be achieved when using longwall panel and pillar systems. (Wardell, p. 41, 1969). A large portion of a major harbor in Germany was lowered more than one meter with minimal subsidence damage by careful control of mining. (Legger, pp. 374 83, 1972). Simultaneous harmonic extraction of superimposed coal seams and special arrangements of the mine workings and overlying structures can be used to limit damage (Brauner, Vol. II, p. 23, 1973; Kratzsch, p. 15, 1964; Osterwald, pp. 349 53, 1961; USGS p. 68, 1962). Longwall mining commonly results in predictable and controlled subsidence that is 90 95 percent completed by the termination of mining (National Coal Board, p. 90, 1974; Wardell, p. 36, 1969; Voight, p. 739, 1970). Room-and-pillar mining, on the other hand, may result in subsidence at a much later date, especially when conducted at shallow depths (Amuedo and Ivey, IV 3, 1975, Dunrud and Osterwald, p. 43, 1978).

One measure which can reduce material damage from subsidence is to reinforce or design surface structures to resist the stress imposed on them by subsidence-caused ground movements (National Coal Board, p. 65, 1974; Voight, p. 720, 1970; and Brauner, Vol II, p. 15, 1973).

Another measure which can significantly reduce subsidence is placement of fill, whether hydraulically or pneumatically, behind a longwall face (Brauner, p. 33, 1973). Backfilling through surface bore holes has also been used by the Bureau of Mines in an attempt to limit subsidence over abandoned room and pillar mines (DOI, USBM, pp. 8 22, 1976).

Some commenters on the proposed regulations suggested deleting Sections 817.121 817.126 altogether, and allowing State regulatory agencies to establish individual regulations regarding subsidence. This alternative was rejected by the Office because Section 516(b)(1) of the Act specifically requires an operator to "adopt measures consistent with known technology in order to prevent subsidence causing material damage to the extent technologically and economically feasible . . .'' and because the Office feels that the state of the art is such that minimum national standards can be set. In such circumstances, Section 501(b) of the Act mandates these regulations be promulgated. While a State can tailor its subsidence controls as it deems appropriate, within the limits set under Subchapter C of these rules, the Office believes that minimum national standards are appropriate to fulfill the statutory goals of protection against subsidence damage and to prevent operators in one State from having unfair competitive advantages. (See Section 102(g) of the Act).

A revision of Sections 817.121 through 817.126 has been made by the Office since the proposed regulations, based on numerous comments addressed in the paragraphs below. The major changes are: (1) deletion of proposed Section 817.123 on the basis that a preliminary survey at the request of the landowner is not required by the Act and would be burdensome to the operator without sufficient offsetting environmental or property protection values to warrant the burden; (2) deletion of proposed Section 817.125 because monitoring is expensive and burdensome, often does not contribute to the prevention of subsidence, and is not appropriate or necessary in all circumstances to achieve the purposes of the Act; and (3) proposed Section 817.124 is modified to strengthen surface owner and public protection from surface damage caused by mine subsidence.

Sections 817.121-817.126 must be read together with Section 784.20 which contains permit application requirements for the subsidence control plan. The reader is encouraged to read the preamble discussion of Section 784.20 for a discussion of many issues relating to Sections 817.121-817.126.

SECTIONS 817.121 Subsidence control: General requirements.

Section 817.121 establishes general requirements for subsidence control. The basic principle of this Section is to require prevention of subsidence damage, to the extent that it is economically and technologically feasible, and to maintain the value and foreseeable use of surface lands. This Section allows planned or controlled subsidence, and specifies that room and pillar mining is not prohibited. It further obliges the operator to comply with the subsidence control plan of Section 784.20. All measures should take into account that often there is a long lag time between mining and subsidence damage appearing at the surface.

A sentence has been added to Section 817.121(a) to make the regulations agree with the Act, Section 516(b)(1), concerning room and pillar mining.

Section 817.121(b) repeats a reference to the permit section of the regulations and has been left as the introductory Section of this group of regulations to remind the user that underground mining activities must conform with the permit requirements relating to subsidence control.

Several comments on this Section stated that operators who own the surface above an underground mine, as well as the mine, should be exempt from subsidence control plans, and operators should be exempt in areas where the surface owner agrees to accept subsidence and damage to structures, either by formal waiver or by an unspecified form of agreement. This concept was rejected by the Office because Section 516(b)(1) of the Act specifically protects the surface environment for the present and future, regardless of ownership. The Act does not contemplate that private parties can, by contract or purchase of resources, void the Congressional mandate for environmental and other property protection.

Another commentor suggested that the regulations do not allow operators to prove that subsidence will not occur, nor do they establish liability for subsidence caused by previous operations in permit areas. This comment did not lead to any changes in the rules because subsidence of the surface over mined-out areas is a proven fact (Dunrud and Osterwald, pp. 40 43 and 77, 1978) and the Office has not been presented with any evidence that subsidence can be definitively precluded as a possibility in any circumstances. As for past mining, the current operator takes the land as he finds it, and if the likelihood of subsidence is increased during the current operation as a result of voids created earlier, that operation is as liable for the damage as though the increased likelihood resulted from natural conditions. Accordingly, the regulatory scheme has been developed to evaluate susceptibility of surface to damage and development of mitigating measures.

One commenter stated that underground operators should be required to conform to the same surface restoration standards as surface operators. This suggestion was rejected because it was beyond the scope of the specific requirements in Section 516(b)(1) of the Act, and because subsidence from underground mines and surface mining have significantly different effects on the surface. For example, topsoil removal, overburden stripping, and vegetative removal will all occur in surface mining but probably will not accompany subsidence, so that identical restoration measures are inappropriate. See the proviso in Sections 516(a) and 516(b)(10) of the Act.

Several comments suggested inserting standards for "planned'' or "controlled subsidence'' into the regulations, rather than specifying subsidence prevention and damage mitigation measures. These suggestions were rejected because longwall mining is not appropriate for all coal seams. It is very expensive when the coal seam is in excess of a 30 degree slope, and it is not economically feasible for all operations. The adequacy of the proposed longwall plan, if any, can be evaluated by the regulatory authority based on the submission under Section 784.20, and detailed technical standards in these rules would be voluminous, without adding materially to lessen the damage.

One comment was received which stated that Section 817.121 restricted methods of operation to the point of making them uneconomical. The Office feels that the wording ". . . economically feasible . . .'' allows the operator a choice of mining methods.

SECTION 817.122 Subsidence control: Public notice.

Section 817.122 requires the operator to distribute the mining schedule by mail to all property owners and residents in the affected and adjacent areas, and specifies that each person shall be notified at least six months prior to mining beneath that person's property or residence. The mining schedule must include all future mining planned to occur which might cause subsidence damage to the property.

The six-month notification is provided so that the landowner will be informed of the potential for subsidence damage to the property prior to its being undermined. The six-month requirement allows a reasonable length of time prior to the earliest onset of subsidence so that damage-control measures may be implemented, and adverse effects of subsidence may be mitigated. The Office has not specified the maximum period before undermining within which the notice must be sent, but it is expected that regulatory programs will provide a reasonable period to ensure adequate protection for the surface owner. Notification to the landowner at the beginning of subsidence is not an acceptable alternative, since this would pose a direct and unanticipated danger to the life and property of the landowner. (GAI, 1974).

Utilities, municipalities, and industries must also be advised as to when disruptions are possible and must be allowed adequate time to protect against loss of power, gas, or water services. If landowners are to assure their rights by means such as insisting that proposed subsidence controls be modified, then they must be informed of the possibility of subsidence affecting their land prior to its occurrence and, in many cases, prior to mining.

Notification to landowners and residents by publication of the mining schedule in a newspaper, as proposed, has been deleted. Section 817.122 now only requires notification by mail. The Office believes that notice by mail is a reasonable and more reliable form of notification than publication in a newspaper. Newspaper notification is not required by the Act.

Suggestions to delete proposed references in Section 817.122 to premining surveys, and the probable effects on structures, were accepted. The Office believes that the premining survey would be potentially very burdensome on the operator, of minimal benefit, and is not specifically required by the Act. Accordingly, proposed Section 817.123, which provided for such surveys, has been deleted. (See discussion below). An itemization of the probable effects of subsidence on structures would most likely be so speculative or general as not to be useful to the property owner.

Suggestions to limit Section 817.122 to areas of longwall mining, planned subsidence and areas known to fail within 10 years, were rejected by the Office because Section 516(b)(1) of the Act specifically requires limitation of material damage from unplanned subsidence.

A request to change the notification time schedule to every 12 months was rejected. The Office believes a single pre-mining notice approximately six months before the mining will provide adequate warning to landowners and other persons whose property is likely to be affected.

SECTION 817.123 Deleted

In the proposed regulations, Section 817.123, which has been deleted in these final rules, would have provided that the regulatory authority would, upon a request by an owner of any dwelling or structure within the mine plan area, require the operator to conduct and submit to the regulatory authority a premining survey. This Section also would have required a premining survey of all public buildings and structures in the mine area. These requirements were proposed to provide a baseline against which to measure damages that might occur. In this manner they protected both the surface owner and the operator. Special attention in the survey was to be given to the condition of water structures and systems used to supply human, animal, and agricultural needs. The operator would have been required to provide the surface owner and the regulatory authority with copies of the premining survey report. The report was to include a description of special conditions and proposed adjustments to the subsidence control procedures of proposed Section 817.122.

Some commenters on this Section suggested deleting the entire Section and allowing States to establish individual regulations. Other suggestions were that the premining survey be included in the subsidence control plan; that provisions be made for waiver of damage claims by granting severance deeds of record to the operator; that temporary dwellings such as tents, mobile homes, and the like be specifically exempted from the "dwelling'' provision; that the surface owner request a survey directly from the operator, rather than from the regulatory authority; and that surveys should be limited to assessment of potential effects of future operations during the term of the permit.

During the period of consideration of public comments, the Office concluded that the Act does not require a premining survey and that to include such a requirement in the regulations would place an unwarranted burden on operators. It was further concluded that the optional nature of the proposed regulation which left the decision to the property owner of whether or not to request a survey did not provide a reasonable basis for evaluating ultimate liability for damage. For these reasons, and because of the reorganization of Sections 817.121 817.126 and the shift of emphasis in Section 817.124 to increased liability and restoration requirements following subsidence, proposed Section 817.123 has been deleted in its entirety. However, an inventory of surface features subject to material damage is now required under Section 784.20.

SECTION 817.124 Subsidence control: Surface owner protection.

Section 817.124 provides protection for the rights of owners of surface lands or structures by stipulating that underground operators shall use all measures approved by the regulatory authority to reduce, control, or prevent subsidence and subsidence-caused damage. Operators of mines that cause subsidence-related damage are required to mitigate the damage by restoration, rehabilitation, or removal and replacement of structures; purchase of the damaged structure or feature and restoration of surface to premining capability; or by providing surface owners with prepaid insurance to cover the amount of diminution in value caused by subsidence or other similar protection. In the case of land-use degradation caused by subsidence, operators are required to return the surface to a condition capable of supporting uses reasonably foreseeable before subsidence.

Dwellings or other buildings already constructed may be partially protected against subsidence by reinforcement of sensitive parts such as windows or doors and by isolating the structure from lateral ground movement by ditching around its periphery (National Coal Board, p. 65, 1974; and Voight, p. 737, 1970). New structures can be designed to resist subsidence by incorporating flexible superstructures, flexible pipelines with telescopic joints, special sliding or rigid raft type foundations and by locating the long axis of the building properly with respect to mining (National Coal Board, p. 65, 82, 1974; Pennsylvania DER, 1974; Vought, 737, 1970; and Pennsylvania DER, p. 62, 1966). The requirement to identify mining areas, dates and probable effects of surface subsidence (Sections 817.122 (a), (b) and (c)) will enable the landowner to implement precautionary measures.

Suggestions from commenters to require that insurance against subsidence damage be made available to affected persons in all cases were rejected, because the Office feels that such insurance may prove to be prohibitively expensive in some instances and not readily available in others. Accordingly, insurance is one alternative from which operators can choose to meet the requirements of this Section, but is not required.

Several comments on Section 817.124 questioned whether the underground operator should be required to protect surface structures or land in cases where the operator either owns the surface or has a specific waiver of damage. The Office has modified this Section because of the shift of emphasis in subsidence control imperatives but has retained the basic tenets of surface protection for both present and future owners, as mandated by the Act's requirement for maintenance of the surface's value and reasonably foreseeable future uses. (Section 516(b)(1) of the Act).

Several suggestions dealt with language of the proposed regulations. Most concerned the concept of consultation by operators with surface owners as provided in the proposed Section 817.124. As stated above, the Office's modification of this Section has incorporated alternatives to the "consultation'' concept suggested by commenters by providing options for the operator and protection for the surface owner. This is consistent with the Act in that it recognizes that coal is necessary to meet our energy needs and also recognizes that the environment must be protected from the adverse consequences of mining.

Some commenters urged deleting Section 817.124 entirely and allowing States to formulate individual regulations regarding surface owner protection. These suggestions were rejected. The Office felt that to allow multiple and unrelated regulations would result in many programs with no predictable unifying theme or minimum criteria. Section 501(b) of the Act requires the Office to develop minimum procedures, which is what this regulation does. Further protection can be provided under the approved regulatory program. The Office believes that Congress enacted Section 516(b)(1) of the Act in part because State initiative has not in the past adequately met the subsidence damage problem. These rules intend to set the minimum standards for future State regulation. Section 817.124 is appropriate in that it provides options for the operator while providing protection to the surface owner and surface resources in accordance with the intent of the Act. The consultation requirement has been deleted because it presented no real protection, while affording the surface owner an opportunity unfairly to interfere with mining plans by refusing to consult.

A suggestion that underground mining should be prohibited in areas where subsidence cannot be prevented by known technology was rejected because its intent would far exceed the intent and plain meaning of the language of the Act. The Act recognizes that subsidence cannot always be prevented, but attempts to lessen the effects of subsidence, through planning. Section 817.124 has been redrafted to strengthen protection of the surface owner and surface values from damage caused by mining. This revised Section provides increased protection to the surface owner while still providing options to the mine operator, consistent with the intent of the Act that mining be allowed to proceed in most cases.

SECTION 817.125 Deleted

In the proposed regulations, Section 817.125 would have required operators to establish a scheme for monitoring the amount of subsidence caused by underground mining, and specified reports of subsidence to be updated periodically and given to the regulatory authority.

Many comments were received concerning this Section, all of which questioned the requirements of monitoring. After careful consideration, the Office has determined that monitoring programs are not specifically required by the Act; that monitoring can be expensive, as demonstrated by the Bureau of Mines and the Old Ben Coal Co. on a monitoring program in the Illinois coal basin; and that monitoring is a means of determining movement and not a reliable method of preventing or mitigating subsidence or resulting damage.

Accordingly, Section 817.125 has been deleted, and its intent of surface owner protection has been shifted to the more direct provisions of Section 817.124.

SECTION 817.126 Subsidence control: Buffer zones.

Section 817.126 provides protection for hydrologic structures, aquifers, public buildings, and communities by preventing underground mining beneath or adjacent to these structures where subsidence damage is likely to occur. The regulatory authority is given the option of determining where mining may be permitted.

Paragraph (a) provides for the protection of perennial streams and major impoundments (20 acre-feet or greater) from underground mining operations and gives the regulatory authority the option of allowing mining near these areas if it can be shown that subsidence will not cause material damage to these water features. It further provides for corrective measures to be taken if material damage from subsidence occurs as a result of mining operations.

Protection of aquifers serving as a significant source of water supply to any public water system is required by Section 817.126(b). Additional protection is provided in that the regulatory authority may suspend mining or limit the percentage of coal extraction where an aquifer may be subject to subsidence damage.

Public buildings are protected from adverse surface damage from underground mining operations in Section 817.126(c) by prohibiting mining beneath or in close proximity to these structures. This requirement may be waived by the regulatory authority if it can be shown that subsidence from mining beneath these structures will not cause material damage.

Section 817.126(d) provides the regulatory authority with the option of suspending underground coal mining in all of the above circumstances where there is a threat of imminent danger to inhabitants of urban areas, cities, towns or communities.

The Office feels that this Section provides an addtional level of protection to the public in and around areas of active underground coal mining.

One commenter suggested deletion of Section 817.126 to permit individual States to develop separate regulations. The Office feels that a single approach to protection of surface facilities will provide consistency of regulation, and, therefore, has rejected the suggestion.

Some commenters requested that the Office not regulate mining beneath intermittent streams. The Office has determined that to prohibit all mining under intermittent streams exceeds the intent of the Act (See Section 516(c) which authorizes suspension of mining under "permanent streams'') and that the cost of implementing measures to prevent disturbance of intermittent streams is contrary to Section 516(b)(1) of the Act which requires implementation of measures which are "technologically and economically feasible.'' While the intermittent stream provision which appeared in the proposed regulations has been deleted from this Section as too broad (there was no depth beyond which it didn't apply), the operator still must comply with the buffer zone provisions of Section 817.57, if applicable to the stream in question.

Commenters suggested that only mining activity likely to cause subsidence should be regulated by Section 817.126 and that mining should be permitted under structures where planned subsidence would cause no damage, where surface owners were suitably compensated, or where a deed granting relief exists. These suggestions were rejected because language regulating only mining likely to cause subsidence violates the Act which calls for measures to prevent material damage, and the fact that its likelihood is remote does not warrant an exemption from the requirement. The regulations as written cover both planned and unplanned subsidence and provide protection to public buildings in accordance with Section 516(c) of the Act. The contents of a deed are irrelevant to preserving the value and forseeable use of surface features.

Comments suggesting that the volume of protected impoundments be reduced from 20 acre feet to five acre feet were rejected because the suggested volume is far too small to qualify as a major impoundment as specified in Section 817.49 and Part 77.216(a)(1) of MSHA regulations. The reader is referred to the preamble discussion of Section 816.49 for a discussion of the rationale for the 20 acre foot cut-off.

Commenters suggested that the regulatory authority be allowed the option of permitting mining under structures where it determined that no subsidence damage will result. This provision is now found in both Paragraphs (a) and (c).

The last sentence of Section 817.126(a) has been modified to require corrective action if damage is caused, in order to comply with Section 516(b)(1) of the Act, in a manner which does not restrict the operation to specific types of corrective measures. Now the measures most appropriate for the site can be implemented.

Section 817.126(b) has been modified in response to comments to read "any aquifer that serves as a significant source of water supply to any public water system.'' This suggestion was incorporated into the regulations since many towns and cities obtain significant portions of their water from more than one source. This modification provides additional protection to the public over the proposed rules which only protected aquifers which were the "sole'' source of supply. Protection of private water supply wells affected by damaged aquifers is assured by Section 783.18 of these regulations. I11Section 817.126(d) was added to implement Section 516(c) of the Act concerning the presence of imminent danger from mining operations.

Several comments were received concern in the term "adjacent'' in Section 817.126(a). The Office feels that guidance as to the appropriate definition of this term can be found in Section 817.57 of the regulations and refers interested readers to the preamble discussion for that Section. Of course, State programs can more specifically define this concept as long as adequate protection for the water body is assured. The intent of the word "adjacent'' is to prohibit activities which may cause subsidence in such proximity to streams and impoundments that the functioning of the feature might be jeopardized. As noted above, the angle of draw, within which subsidence can occur, may be as great as 70 degrees and should be taken into account in the context of determining appropriate distances within which not to mine.

SECTIONS 817.131 and 817.132 Cessation of operations.

These Sections are substantially identical to the corresponding Sections of Part 816. The reader is referred to the appropriate portions of the Preamble for Sections 816.131 816.132 for information concerning the technical basis and statutory authority for these Sections. In addition to the Sections of the Act cited in those portions of the Preamble, these Sections are based on Section 516 of the Act. All issues considered for Sections 816.131 and 816.132 were also considered for these sections and similarly decided. (Additional comments received on specific parts of Sections 817.131 and 817.132 are addressed below:)

{15277}Section 817.131(a).

Several commenters suggested the deletion of this paragraph entirely. However, temporary interruption in production operations still necessitates ventilating and maintaining underground entries and/or passageways, hence closure of surface access openings is not appropriate and would be unsafe and unacceptable. There are many areas in underground mines where production ceases at some normal phase of the total mine operations, which could fall in the temporary category as formerly proposed and yet still be required for total mine production. As a result, the wording "maintain all surface access openings'' was added to make it clear tht a partial closing does not require complete shutdown.

Section 817.132(a).

Several commenters suggested that the phrase "this Chapter and according to'' be deleted from Section 817.132(a). They contended that current State regulations for shaft and/or portal sealing together with an approved State regulatory program would suffice and not require the phraseology originally proposed. This suggestion was rejected. By deleting "this Chapter and according to'', this Section could be interpreted as superseding the specifics contained elsewhere in this Chapter, including Sections 817.13, 817.15, 817.101 817.117 and others, which is not the intent.

Section 817.132(b).

Several commenters suggested various revision to this Section. The suggestion was made that only surface equipment, structures, or other facilities not required or approved shall be removed. This suggestion was accepted, as underground equipment, structures, and equipment should not have to be removed if their remaining poses no threat to the environment or public safety. Also, when an operation is ceased permanently all entrances to the underground mine will be sealed and the equipment should pose no threat to the environment or the health and safety of the public.

SECTION 817.133 Post-mining land use.

This Section is substantially identical to the corresponding Section of Part 816. The reader is referred to the appropriate portions of the preamble for Section 816.133 for information concerning the statutory authority, technical basis and alternatives considered for this Section. In addition to the statutory authority cited in Section 816.133, authority for this Section is found in Section 516 of the Act. The Office considers the needs for post-mining land use controls to be sufficiently similar to warrant substantially identical criteria for both surface and underground operations.

Several commenters raised issues related to specific sections of Section 817.133 which were also raised in connection with Section 816.133: These issues are discussed and resolved in the preamble to Section 816.133 and revised language has been incorporated in Section 817.133 where changes were also made in Section 816.133. These issues include objections to: (1) the phrase "and had been properly managed'' in Sections 816.133(b) and 817.133(b); (2) the compatibility requirement of Sections 816.133(c)(1) and 817.133(c)(1); (3) the letter of commitment required under Sections 816.133(c)(4) and 817.133(c)(4) and (4) the inclusion of "other appropriate professionals'' in Sections 816.133(c)(5) and 817.133(c)(5).

In addition, editorial changes in Section 816.133 made since the proposed regulations and changes made in connection with the Office's consideration of comments on Section 816.133 have also been made in Section 817.133. These changes include: (1) addition of "before permanent abandonment'' in Section 817.133(c) (introductory paragraph); (2) the 60-day notice requirement in Section 817.133(c)(1) and (c)(8); (3) deletion of "needs'' in Section 817.133(c)(2) and (4) the reference to the bonding regulations sections in Section 817.133(c)(9).

Some commenters suggested that the differences between surface and underground mining operations mandated that Sections 816.133 and 817.133 not be identical. Specifically, these commenters stated that Sections 817.133(b) and 817.133(c) should be revised to take into account the long life of an underground mine. The Office considered making revisions to Section 817.133 to reflect differences in undeground mining as well as the alternative of making no change. Reviewers apparently overlooked the fact that each five year phase of an underground mining operation must be separately permitted. (Section 782.17). (There are exceptions if an operator can make the necessary showing under Section 786.25(a) of the regulations.) Thus, for most operations there are essentially no differences in planning post-mining land uses for the two types of mining. Therefore, while language has been added in Section 817.133(a) to reflect that surface land areas affected by mining (as opposed to "all affected areas'') are of concern in underground operations, no other changes to this section were made.

SECTIONS 817.150-817.176 Roads.

These Sections have been developed to implement permanent environmental protection performance standards for the design, construction, reconstruction, utilization, maintenance, and restoration of roads at underground coal mining operations. These regulations are aimed at ensuring that the mine road operations will not pollute water resources, or damage fish and wildlife habitat, or public or private property. Authority for these sections is found in Sections 102, 201, 501, 503, 504, 515, 516, and 701 of the Act.

These sections are substantially like the corresponding sections of Part 816. The reader is referred to the appropriate portions of the Preamble for 30 CFR Part 816 for information concerning the technical basis, alternatives considered, rationale for the regulations adopted, disposition of comments, and statutory authority for these sections. Every comment received on the mine road regulations was looked at both from a surface and underground mining activity perspective and disposed of similarly for both mining situations.

Permanent regulations for roads used in connection with underground mining activities incorporate the three-tier road classification system. The definition of each class of road is found in 30 CFR 701.5 and is based upon the planned volume of traffic, speed, and weight of vehicle used above ground, outside of the underground mine workings. There is nothing in the nature of the kind of surface or underground coal mining activities that would lead to distinctly different road requirements and regulations for surface mines as opposed to deep mines.

The organization of the three types of road classifications are as follows:

Class I Roads_Sections 817.150 817.156

Class II Roads_Sections 817.160 817.166

Class III Roads_Sections 817.170 817.176

The correlation between the proposed regulations and the final regulations is shown in the following chart:

_______________________________________________________________________ Proposed Subject Final Class Class Class Regular I II III tions General 817.31 817.150 817.160 817.170 Location 817.32 817.151 817.161 817.171 Design and Construction (including erosion control) 817.33 817.152 817.162 817.172 Roads: Drainage 817.34 817.153 817.162 817.173 Surfacing 817.35 817.154 817.164 817.174 Maintenance 817.95 n1 817.155 817.165 817.75 Restoration of Roads 817.38 817.156 817.166 817.176 ____________________________________________________________________________ n1 Also includes: 817.31(a).

{15278}1. Many comments regarding roads carried the dual designation of both surface and underground mining. The disposition of these comments is discussed in the preamble for 30 CFR Part 816. The following additional comments limited only to roads related to underground mining, were also received:

2. A commenter suggested allowing variances for site-specific conditions on the grade requirements for pre-existing roads. This concern is covered by the existing structures provisions of 30 CFR 701.11(e), 784.12 and 786.21. This comment, all was considered in developing new requirements for the three classes of roads which are appropriately based on the volume of traffic, and the weight and speed of vehicles using the road. (U.S. Forest Service 1977 Sections 24; Parker, P.E. 1965 Fig. 1; Kaufman 1977. p. 19.)

3. Some comments objected to the requirement to crown or reslope a road to a drainage ditch. Others objected to a 1/2 inch per foot for crowning or resloping and proposed a 1/4 inch standard. The reader is referred to the preamble discussion of 30 CFR 816.152(d)(10) and 816.162(d)(10) for information and rationale for changing to a 1/4 inch standard.

4. A few comments expressed concern over the rigid 24-inch lift restriction proposed for road embankments. The comments urged greater flexibility for site-specific conditions and that a maximum lift thickness of 4-feet be allowed instead of 24-inches as proposed. Construction of embankments for roads in several States must be on 12-inch lifts. The Office has revised the standards to an upper limit of 36-inches for Class I and Class II Roads. The Office has not established lift standards for Class III Roads due to side cast construction procedures (Kaufman, 1977 fig. 18). The reader is referred to the Preamble discussion of Sections 816.150 816.176 for further information on this subject.

5. Some commenters objected to the word "horizontal'' in proposed Section 817.33(c)(3) stating it is an unworkable condition to require a horizontal lift placement on a vertical grade. The Office recognized this problem and changed the language for Class I and Class II Roads to read, "spread in successive uniform layers.''

6. A few comments objected to compaction requirements in Section 817.33(c)(5),(6). The reader is referred to the Preamble discussion of Section 816.152(d)(5)(6) and 816.162(d)(5)(6) for information and rationale for the final standard.

I117. few comments suggested proposed Section 817.38(b) be deleted entirely. The comments suggested the removal and disposal of all road-surfacing materials was unnecessarily restrictive. The rationale was that road surfacing in many cases is a limestone or slag by-product and not asphalt. Therefore, complete removal of the nonasphalt material would be unnecessary. The Office did not believe a language change was needed. The interpretation of 30 CFR 817.156(b) and 816.166(b) is that unsuitable road material which is detrimental to vegetation establishment and growth shall be disposed in accordance with 30 CFR 817.89, and that other surfacing material may be sacrificed, topsoiled and revegetated if authorized by the regulatory authority.

SECTION 817.180 Other transportation facilities.

1. The authority, basis and purpose of Section 817.180 is the same as for Section 816.180 of Subchapter K, except that Section 516 of the Act provides additional statutory authority. The reader is referred to the preamble discussion of 30 CFR Section 816.180 for a discussion of issues relevant to Section 817.180.

This Section is intended to ensure that transportation facilities other than roads, which are located within the mine plan area are constructed, reconstruced, used and maintained in a way that furthers the environmental and other goals of the Act.

Section 817.180(a) identifies specific environmental situations which must be addressed by the mine operator during the design, construction and use of these transportation facilities. These performance standards will assure compliance with Sections 516(b)(9) and (11) of the Act.

Sections 817.180(b) (d) addresses the minimization of damage to other related environmental values, als