ENVIRONMENTAL
QUALITY BOARD[ 25 PA. CODE CHS. 87, 88 AND 90 ] Remining Requirements [45 Pa.B. 5920]
[Saturday, October 3, 2015]The Environmental Quality Board (Board) proposes to amend the remining regulations in Chapter 87, Subchapter F, Chapter 88, Subchapter G and Chapter 90, Subchapter F (relating to surface coal mines: minimum requirements for remining areas with pollutional discharges; anthracite surface mining activities and anthracite bank removal and reclamation activities: minimum requirements for remining areas with pollutional discharges; and coal refuse disposal activities on areas with pre-existing pollutional discharges) to read as set forth in Annex A. This proposed rulemaking incorporates requirements of the Federal remining rules in 40 CFR Part 434, Subpart G (relating to coal remining) and the statistical methods in 40 CFR Part 434, Appendix B (relating to baseline determination and compliance monitoring for pre-existing discharges at remining operations).
This proposed rulemaking was adopted by the Board at its meeting of May 20, 2015.
A. Effective Date
This proposed rulemaking will be effective upon final-form publication in the Pennsylvania Bulletin.
B. Contact Persons
For further information, contact Thomas Callaghan, PG, Director, Bureau of Mining Programs, Rachel Carson State Office Building, 5th Floor, 400 Market Street, P. O. Box 8461, Harrisburg, PA 17105-8461, (717) 787-5015; or Joseph Iole, Assistant Counsel, Bureau of Regulatory Counsel, P. O. Box 8464, Rachel Carson State Office Building, Harrisburg, PA 17105-8464, (717) 787-9376. Information regarding submitting comments on this proposed rulemaking appears in Section J of this preamble. Persons with a disability may use the AT&T Relay Service, (800) 654-5984 (TDD users) or (800) 654-5988 (voice users). This proposed rulemaking is available on the Department of Environmental Protection's (Department) web site at www.dep.state.pa.us (select ''Public Participation Center,'' then ''The Environmental Quality Board'').
C. Statutory Authority
This proposed rulemaking is authorized under the authority of section 5 of The Clean Streams Law (35 P. S. § 691.5), sections 4(a) and 4.2 of the Surface Mining Conservation and Reclamation Act (52 P. S. §§ 1396.4(a) and 1396.4b) and section 1920-A of The Administrative Code of 1929 (71 P. S. § 510-20).
D. Background and Purpose
The Commonwealth's existing remining program is implemented through Chapter 87, Subchapter F, Chapter 88, Subchapter G and Chapter 90, Subchapter F, as well as through technical guidance documents and individual permits. The regulations allow liability protection for remining operations conducted on abandoned mine lands with existing pollutional discharges by enabling the Department to determine the pollution baseline at a site and set effluent limitations accordingly. Currently, the Department determines the pollution baseline using a single statistical method (Method 1), explained as follows, and incorporates the baseline in the individual permit. Likewise, effluent limitations are determined on a case-by-case basis.
Federal remining requirements are found in 40 CFR Part 434, Subpart G and Appendix B. The Federal requirements differ from the Pennsylvania requirements by providing the option of employing an alternative statistical method (Method 2) for determining the pollution baseline. The choice of methods depends on which method would more accurately characterize baseline levels due to site-specific factors.
The Federal regulations further provide for remining in cases in which the pollution baseline cannot be determined due to infeasibility of sampling and remining would result in significant water quality improvement that would not otherwise occur. Under these circumstances, the Federal regulations require an operator to submit a pollution abatement plan based on best management practices (BMP) without regard for numeric effluent limitations.
The preambles of the Federal remining regulations, proposed at 65 FR 19440 (April 11, 2000) and adopted at 67 FR 3370 (January 23, 2002), provide extensive additional background references explaining the statistical methods, BMPs and other requirements. Notably, the Federal regulations were informed by the extensive experience with remining in this Commonwealth.
The proposed rulemaking incorporates into the Commonwealth's regulations both statistical methods provided in the Federal regulations, eliminating the need to implement the methods through individual permits and providing flexibility regarding the choice of statistical method based on site-specific factors. The proposed rulemaking further provides for remining at sites in which it is infeasible to establish pollution baselines.
Summary of the Federal regulations
40 CFR Part 434, Subpart G
Subpart G of 40 CFR Part 434 includes specialized definitions, applicability and effluent limitations for remining.
The following definitions are included in 40 CFR 434.70 (relating to specialized definitions): ''coal remining operation,'' ''pollution abatement area,'' ''pre-existing discharge,'' ''steep slope'' and ''new source remining operation.''
Section 434.71 of 40 CFR (relating to applicability) includes a description of mine sites to which the regulations apply, requirements for water that is intercepted by remining activities, a grandfather clause for existing approved remining authorizations and a description of the time period during which the regulations apply.
The effluent limitations are established in four categories: best practicable control technology currently available (BPT); best available technology economically achievable (BAT); best conventional pollutant control technology (BCT); and new source performance standards (NSPS).
The BPT limitations in 40 CFR 434.72 (relating to effluent limitations attainable by the application of the best practicable control technology currently available (BPT)) are the most commonly applicable. The Federal BPT regulations require a site-specific pollution abatement plan designed to reduce the pollution load. They also establish numerical effluent limitations for pre-existing discharges for total iron, total manganese, net acidity and total suspended solids. These effluent limitations may not exceed the baseline pollution load, as defined under the methods described in 40 CFR Part 434, Appendix B. The BPT limitations also allow for circumstances under which the numerical limitations are not applicable, specifically in cases in which it is infeasible to collect samples to establish the baseline pollution load.
The BAT limitations in 40 CFR 434.73 (relating to effluent limitations attainable by application of the best available technology economically achievable (BAT)) require a pollution abatement plan and compliance with the baseline pollution load for net acidity, iron and manganese.
The BCT limitations in 40 CFR 437.74 (relating to effluent limitations attainable by application of the best conventional pollutant control technology (BCT)) require a pollution abatement plan and compliance with the baseline pollution load for total suspended solids.
The NSPS limitations in 40 CFR 434.75 (relating to new source performance standards (NSPS)) require a pollution abatement plan and compliance with the baseline pollution load for acidity, iron, manganese and total suspended solids.
40 CFR Part 434, Appendix B
Appendix B of 40 CFR Part 434 includes the statistical methods for establishing the baseline pollution load and determining compliance with the numerical effluent limitations. There are two methods (Method 1 and Method 2) to establish the baseline provided in Appendix B. There are also two time frames to determine compliance, one on a monthly basis (single-observation) and the second on an annual basis. The thresholds to determine compliance are referred to as triggers.
Method 1 for the single-observation trigger uses a statistical method that determines the tolerance interval of the 95th percentile above the median and compares that value with the sample being evaluated. Method 2 for the single-observation trigger is a nonparametric estimate of the 99th percentile of loadings. Method 1 for the annual trigger compares the baseline with 1 year's monitoring data for loading using the 95th percentile confidence interval for the median of each data set. Method 2 for the annual trigger uses the Wilcoxon-Mann-Whitney test to compare the baseline and monitoring year being evaluated. The Wilcoxon-Mann-Whitney test is a ranking test.
When the single-observation trigger is exceeded in 2 consecutive months, accelerated (weekly, for 4 weeks) monitoring is required. If the accelerated sampling confirms the exceedance, then treatment of the discharge is required. If the accelerated sampling does not confirm the exceedance, then the accelerated sampling may be reduced to a monthly basis.
When the annual trigger is exceeded, treatment of the discharge is required.
Project XL
In April 2000, the United States Environmental Protection Agency (EPA) Region III and the Department entered into an agreement under the EPA's Project XL program which allowed for a modified approach to remining permits. Under this program, the water quality performance for eight pilot study remining sites was evaluated based on stream water quality rather than discharge pollutant loading. Under this project, the basis for water quality evaluation was bimonthly receiving stream concentration data. The triggers were based on concentrations rather than loading.
The conclusion of the pilot study was that remining with in-stream monitoring was just as effective as the traditional discharge-based remining approach. Another conclusion was that the Project XL approach will encourage additional remining since it can be more cost-effective.
This proposed rulemaking deviates from the Federal regulations by requiring, in appropriate circumstances, in-stream baseline determinations and monitoring.
Mining and Reclamation Advisory Board collaboration
The Department collaborated with the Mining and Reclamation Advisory Board's (MRAB) Regulation, Legislation and Technical Committee to develop this proposed rulemaking. At its October 23, 2014, meeting, the MRAB voted for the proposed rulemaking to move forward in the regulatory process.
E. Summary of Proposed Regulatory Requirements
In drafting the proposed rulemaking, the Federal regulatory language was edited and inserted to fit the context of the Commonwealth's regulations. The edits include renumbering, formatting and substitutions of more specific references. For example, when the Federal regulations use ''permitting authority,'' ''Department'' was substituted.
Some other proposed amendments are included to reflect current requirements that are included as permit conditions but will now be addressed in this regulation, instead.
§§ 87.202, 88.502 and 90.302. Definitions
The proposed rulemaking includes proposed definitions of ''coal remining operation,'' ''encountered discharge,'' ''pollution abatement plan,'' ''pre-existing discharge'' and ''steep slope.'' The definition of ''abatement plan'' is proposed to be deleted since this term is replaced by ''pollution abatement plan.'' The definitions of ''coal remining operation,'' ''pollution abatement plan,'' ''pre-existing discharge'' and ''steep slope'' are based on the definitions in 40 CFR 434.70. The definition of ''encountered discharge'' is proposed since it is included in each remining permit issued.
The replacement of the definition of ''abatement plan'' with ''pollution abatement plan'' necessitates amendments throughout the proposed rulemaking to substitute the new term for the old one.
§§ 87.203, 88.503 and 90.303. Applicability
The rulemaking proposes to add §§ 87.203(c) and (d) and 90.303(c) and (d) (relating to applicability). Proposed subsection (c) is based on 40 CFR 434.71(a). Proposed subsection (d) is based on 40 CFR 434.71(c). Proposed amendments to § 88.503(a) (relating to applicability) apply the requirements to anthracite coal refuse disposal activities. Section 88.503(d) and (e) is proposed. Subsection (e) is based on 40 CFR 434.71(c). These proposed subsections establish the circumstances in which this rulemaking will apply.
§§ 87.204, 88.504 and 90.304. Application for authorization
Proposed amendments to §§ 87.204(a)(2)(ii), 88.504(a)(2)(ii) and 90.304(a)(2)(ii) (relating to application for authorization) add flow as a required monitoring parameter because flow data is required to calculate loading. The proposed amendments also add ''total'' as a modifier of aluminum, since the water quality criterion for aluminum is expressed as a total.
Proposed amendments to §§ 87.204(a)(3), 88.504(a)(3) and 90.304(a)(3) reflect the requirements for a pollution abatement plan in 40 CFR 434.72(a). The existing requirements in §§ 87.204(a)(3), 88.504(a)(3) and 90.304(a)(3) are retained to provide more detail of what needs to be in a pollution abatement plan. Requirements in §§ 87.204(a)(3) and 88.504(a)(3) have been in place since 1985, and requirements in § 90.304(a)(3) have been in place since 2001. Each has proven effective.
Proposed §§ 87.204(a)(4) and (5), 88.504(a)(4) and (5) and 90.304(a)(4) and (5) clarify that the pollution abatement plan must include a calculation of the pollution baseline and the data used in its determination. This is currently required through the remining module of the application form for a coal mining permit.
Proposed amendments to §§ 87.204(b), 88.504(b) and 90.304(b) will allow, but not require, applicants to continue water monitoring after the baseline is established, but before the permit is issued. This approach was suggested by the MRAB Regulation, Legislation and Technical Committee. The Federal regulations are silent regarding this period of sampling.
§§ 87.206, 88.506 and 90.306. Operational requirements
Proposed amendments to §§ 87.206(1), 88.506(1) and 90.306(1) (relating to operational requirements) add more specific requirements for the monitoring program. These requirements are currently included in remining permits. Sections 87.206(3), 88.506(3) and 90.306(3), which include the requirement to notify the Department as steps of the abatement plan are initiated and completed, are proposed to be deleted. In addition, proposed amendments to these sections include notification requirements when accelerated sampling is required and to establish the triggers for when this accelerated sampling must begin and when it may end. These triggers regarding accelerated sampling are consistent with the requirements in paragraphs II.A.5 and II.B.5 of 40 CFR Part 434, Appendix B.
§§ 87.207, 88.507 and 90.307. Treatment of discharges
Proposed amendments to §§ 87.207(b), 88.507(b) and 90.307(b) (relating to treatment of discharges) allow for an exception from the requirement to treat individual discharges on sites where it is not feasible to collect samples to establish the baseline pollution load.
Sections 87.207(g)—(j), 88.507(g)—(j) and 90.307(g)—(j) are proposed to be added. Proposed subsection (g) requires a permittee to notify the Department if the treatment obligation is triggered subsequent to accelerated sampling. Proposed subsection (h) provides that the Department will notify the permittee if it has determined that the pollution baseline has been exceeded and that treatment must begin within 30 days of this notice. Proposed subsection (i) requires that encountered discharges be treated to meet the effluent limitations in the permit. Proposed subsection (j) provides clarification as to when the treatment of an encountered discharge may cease.
A cross-reference to § 88.292 (relating to hydrologic balance: effluent standards) is proposed to be added to § 88.507 to clarify that these requirements apply to anthracite coal refuse disposal activities. A cross-reference to § 88.295(b) (relating to hydrologic balance: diversions and conveyances) is proposed to be added to § 88.507(c).
§§ 87.210, 88.510 and 90.310. Effluent limitations
Proposed §§ 87.210, 88.510 and 90.310 (relating to effluent limitations) contain parallel subsections. Subsection (a) requires a pollution abatement plan, which must be approved by the Department and incorporated into the permit as an effluent limitation. Subsection (b) requires that the BMPs included in the pollution abatement plan be implemented. These subsections are based on 40 CFR 434.72(a).
The effluent limitations included in subsection (c)(1) are based on 40 CFR 434.72(b)(1). Subsection (c)(2) includes the exemption from the total suspended solids and settleable solids effluent limitations which are in the footnote to 40 CFR 434.72(b)(1)(iv).
Subsection (d) provides requirements for discharges for which it is not possible to establish the baseline pollutant levels. Subsection (d)(1) is based on 40 CFR 434.72(b)(2). The proposed requirements deviate from the Federal requirements in that they require the establishment of an in-stream baseline under some circumstances, while the Federal requirements do not require in-stream baseline determination under any circumstances. Subsection (d)(2) establishes the bimonthly stream sampling frequency to establish an in-stream pollution concentration baseline. Subsection (d)(3) establishes the monitoring and performance requirements for in-stream comparison with the baseline concentration. Subsection (d)(4) identifies the discharges for which it is not feasible to establish a pollutant baseline. This subsection lists the four categories explicitly identified under 40 CFR 434.72(b)(2). Subsection (d)(4) and 40 CFR 434.72(b)(2) allow for other categories. Subsection (d)(5) specifies the circumstances when in-stream monitoring is not indicative of the impact of remining. These circumstances were based on the experience from many years of observations of the in-stream impacts of remining and Project XL.
Subsection (e) provides for the possibility that pollutants other than iron, manganese, acidity or suspended solids may be eligible for effluent limitations using the approach established by Chapter 87, Subchapter F, Chapter 88, Subchapter G and Chapter 90, Subchapter F.
Subsection (f) identifies the discharges that are subject to the usual effluent limitations and not eligible for the limits established under the remining approach.
Subsection (g) describes when the limitations in subsection (f) are no longer applicable.
Subsection (h) states that the remining effluent limitations apply to eligible discharges until final bond release.
§§ 87.211, 88.511 and 90.311. Baseline determination and compliance monitoring for pre-existing discharges at remining operations
Proposed §§ 87.211—87.213, 88.511—88.513 and 90.311—90.313 contain parallel subsections and incorporate the statistical methods for determining baseline and compliance monitoring from 40 CFR Part 434, Appendix B.
Proposed §§ 87.211, 88.511 and 90.311 (relating to baseline determination and compliance monitoring for pre-existing discharges at remining operations) include procedures to be used for determining site-specific baseline pollutant loadings and for determining whether discharge loadings during coal remining operations have exceeded the baseline loading.
Subsection (a) requires that both monthly and annual compliance monitoring be done. This is based on the requirement in paragraph I.a of 40 CFR Part 434, Appendix B. Subsection (b) requires at least one sample per month for determining the baseline and the annual compliance monitoring period. This is based on the requirement in paragraph I.b of 40 CFR Part 434, Appendix B. Subsection (c) requires the evaluation to be done of the load of the pollutant. This is based on the requirement in paragraph I.c of 40 CFR Part 434, Appendix B. Subsection (d) describes how the load is to be calculated. Subsection (e) allows for the substitution of values when the baseline concentration values are lower than the applicable technology-based effluent limitation guideline. Subsection (f) provides for the exceptions from the substitution of values allowed under subsection (e). Subsection (g) describes how the interquartile range is to be calculated. Subsections (e)—(g) are based on paragraph I.d of 40 CFR Part 434, Appendix B.
§§ 87.212, 88.512 and 90.312. Procedure for calculating and applying a single-observation (monthly) trigger
Proposed §§ 87.212, 88.512 and 90.312 (relating to procedure for calculating and applying a single-observation (monthly) trigger) provide two methods for calculating and applying the monthly trigger for compliance monitoring. Subsection (b) lists the steps for Method 1 for calculating the monthly trigger. This method is the same as the method used by the Department. Subsection (b) is based on paragraph II.A of 40 CFR Part 434, Appendix B. Subsection (c) lists the steps in applying the Method 1 monthly trigger. Subsection (d) lists the steps for Method 2 for calculating and applying the monthly trigger. This is based on paragraph II.B of Appendix B of 40 CFR 434.
§§ 87.213, 88.513 and 90.313. Procedure for calculating and applying an annual trigger
Sections 87.213, 88.513 and 90.313 (relating to procedure for calculating and applying an annual trigger) provide the two methods for calculating and applying the annual trigger specified in section III of 40 CFR Part 434, Appendix B. Subsection (b) lists the steps for Method 1 for calculating and applying the annual trigger. This is the same as the method used by the Department. It is based on paragraph III.A of 40 CFR Part 434, Appendix B. Subsection (c) lists the steps for Method 2 for calculating and applying the annual trigger. Method 2 for the annual trigger is a statistical test which uses ranking of the data. It is based on paragraph III.B of 40 CFR Part 434, Appendix B.
§ 88.509. Criteria and schedule for release of bonds on pollution abatement areas
Proposed amendments to § 88.509(b)(1) (relating to criteria and schedule for release of bonds on pollution abatement areas) include a cross-reference to § 88.287 (relating to vegetation-supporting material: available soil removal), which is applicable to anthracite coal refuse disposal activities. Proposed amendments to § 88.509(c)(1) include a cross-reference to § 88.133 (relating to postmining land use), which is applicable to anthracite surface mines. This is a correction of an omission from the original regulation.
F. Benefits, Costs and Compliance
Benefits
This proposed rulemaking will allow for additional reclamation of abandoned mine lands by providing protection to mine operators from long-term treatment liability. The proposed amendments that allow for remining in circumstances in which calculating the baseline pollution load of discharges is not feasible have the potential to open up areas to remining where it was not previously possible. Remining typically results in substantial improvements in water quality.
Compliance costs
The primary compliance costs are related to water sampling and analysis and implementation of BMPs for the abatement of abandoned mine drainage. However, these costs are part of the planning process for a mine operator when they decide if an area is economically mineable. Overall, compliance costs for a mine operator are reduced since the proposed rulemaking will provide for protection from long-term treatment liability.
Compliance Assistance Plan
Compliance assistance for this proposed rulemaking will be provided through the Department's routine interaction with trade groups and individual applicants. There are about 500 licensed surface coal mining operators in this Commonwealth, most of which are small businesses that will be subject to the regulations.
Paperwork requirements
This proposed rulemaking requires additional information as part of a permit application in the form of a robust pollution abatement plan. Current applicants for remining are required to provide an abatement plan with a remining application. The additional requirements are more focused and may make it simpler to provide the required plans.
G. Pollution Prevention
The Pollution Prevention Act of 1990 (42 U.S.C.A. §§ 13101—13109) established a National policy that promotes pollution prevention as the preferred means for achieving state environmental protection goals. The Department encourages pollution prevention, which is the reduction or elimination of pollution at its source, through the substitution of environmentally friendly materials, more efficient use of raw materials and the incorporation of energy efficiency strategies. Pollution prevention practices can provide greater environmental protection with greater efficiency because they can result in significant cost savings to facilities that permanently achieve or move beyond compliance. Remining operations implement BMPs that result in pollution prevention.
H. Sunset Review
These regulations will be reviewed in accordance with the sunset review schedule published by the Department to determine whether the regulations effectively fulfill the goals for which they were intended.
I. Regulatory Review
Under section 5(a) of the Regulatory Review Act (71 P. S. § 745.5(a)), on September 23, 2015, the Department submitted a copy of this proposed rulemaking and a copy of a Regulatory Analysis Form to the Independent Regulatory Review Commission (IRRC) and to the Chairpersons of the Senate and House Environmental Resources and Energy Committees. A copy of this material is available to the public upon request.
Under section 5(g) of the Regulatory Review Act, IRRC may convey any comments, recommendations or objections to the proposed rulemaking within 30 days of the close of the public comment period. The comments, recommendations or objections must specify the regulatory review criteria which have not been met. The Regulatory Review Act specifies detailed procedures for review, prior to final publication of the rulemaking, by the Department, the General Assembly and the Governor of comments, recommendations or objections raised.
J. Public Comments
Interested persons are invited to submit written comments, suggestions or objections regarding the proposed rulemaking to the Board. Comments, suggestions or objections must be received by the Board by November 2, 2015. In addition to the submission of comments, interested persons may also submit a summary of their comments to the Board. The summary may not exceed one page in length and must also be received by the Board by November 2, 2015. The one-page summary will be distributed to the Board and available publicly prior to the meeting when the final rulemaking will be considered.
Comments including the submission of a one-page summary of comments may be submitted to the Board online, by e-mail, by mail or by express mail as follows. If an acknowledgement of comments submitted online or by e-mail is not received by the sender within 2 working days, the comments should be retransmitted to the Board to ensure receipt. Comments submitted by facsimile will not be accepted.
Comments may be submitted to the Board by accessing eComment at http://www.ahs.dep.pa.gov/eComment. Comments may be submitted to the Board by e-mail at RegComments@pa.gov. A subject heading of the proposed rulemaking and a return name and address must be included in each transmission.
Written comments should be mailed to the Environmental Quality Board, P. O. Box 8477, Harrisburg, PA 17105-8477. Express mail should be sent to the Environmental Quality Board, Rachel Carson State Office Building, 16th Floor, 400 Market Street, Harrisburg, PA 17101-2301.
JOHN QUIGLEY,
ChairpersonFiscal Note: 7-496. No fiscal impact; (8) recommends adoption.
Annex A TITLE 25. ENVIRONMENTAL PROTECTION PART I. DEPARTMENT OF ENVIRONMENTAL PROTECTION Subpart C. PROTECTION OF NATURAL RESOURCES ARTICLE I. LAND RESOURCES CHAPTER 87. SURFACE MINING OF COAL Subchapter F. SURFACE COAL MINES: MINIMUM REQUIREMENTS FOR REMINING AREAS WITH POLLUTIONAL DISCHARGES § 87.202. Definitions.
The following words and terms, when used in this subchapter, have the following meanings, unless the context clearly indicates otherwise:
[Abatement plan—An individual technique or combination of techniques, the implementation of which will result in reduction of the baseline pollution load. Abatement techniques include but are not limited to: Addition of alkaline material, special plans for managing toxic and acid forming material, regrading, revegetation and daylighting.]
Actual improvement—The reduction of the baseline pollution load resulting from the implementation of the approved pollution abatement plan; except that a reduction of the baseline pollution load achieved by water treatment may not be considered as actual improvement.
Baseline pollution load—The characterization of the pollution material being discharged from or on the pollution abatement area, described in terms of mass discharge for each parameter, including seasonal variations and variations in response to precipitation events. The Department will establish in each authorization the specific parameters, including, at a minimum, iron and acid loadings, it deems relevant for the baseline pollution load.
Best professional judgment—The highest quality technical opinion forming the basis for the terms and conditions of the treatment level required after consideration of all reasonably available and pertinent data. The treatment levels shall be established by the Department under sections 301 and 402 of the Federal [Water Pollution Control Act, act of June 30, 1948 (Ch. 758, 62 Stat. 1155)] Clean Water Act (33 U.S.C.A. §§ 1311 and 1342).
Best technology—Measures and practices which will abate or ameliorate to the maximum extent possible pollutional discharges from or on the pollution abatement area. These measures include engineering, geochemical or other applicable practices.
Coal remining operation—A coal mining operation at a site on which coal mining was previously conducted and where the site has been abandoned or the performance bond has been forfeited.
Encountered discharge—
(i) A pre-existing discharge intercepted in the course of active surface mining activities, including, but not limited to, overburden removal, coal extraction and backfilling, or that occurs in the pit, any mining-related conveyance, sedimentation pond or treatment pond.
(ii) The term does not include diversions of surface water and shallow groundwater flow from areas undisturbed by the implementation of the pollution abatement plan which would otherwise drain into the affected area so long as they are designed, operated and maintained in accordance with § 87.105(b)—(g) (relating to hydrologic balance: diversions).
Pollution abatement area—The part of the permit area which is causing or contributing to the baseline pollution load, which shall include adjacent and nearby areas that must be affected to bring about significant improvement of the baseline pollution load, and which may include the immediate location of the discharges.
Pollution abatement plan—Best management practices (BMPs), including, but not limited to, the addition of alkaline material, special handling plans for managing toxic and acid forming material, regrading, revegetation and daylighting, that when implemented will result in reduction of the baseline pollution load.
Pre-existing discharge—
(i) Any discharge resulting from mining activities that have been abandoned prior to the time of a remining permit application.
(ii) The term includes a pre-existing discharge that is relocated as a result of the implementation BMPs in the pollution abatement plan.
Steep slope—
(i) Any slope, including abandoned mine land features, above 20 degrees or a lesser slope as may be defined by the Department after consideration of soil, climate and other characteristics of a region.
(ii) The term does not apply to situations in which an operator is mining on flat or gently rolling terrain, on which an occasional steep slope is encountered and through which the mining operation is to proceed, leaving a plain or predominantly flat area.
§ 87.203. Applicability.
* * * * * (b) Notwithstanding subsection (a), no authorization may be granted under this subchapter for repermitting under §§ 86.12 and 86.14 (relating to continued operation under interim permits; and permit application filing deadlines), permit renewals under § 86.55 (relating to permit renewals: general requirements) or permit transfers under § 86.56 (relating to transfer of permit).
(c) This subchapter applies to pre-existing discharges that are located within or are hydrologically connected to pollution abatement areas of a coal remining operation.
(d) When a coal remining operation seeks reissuance of an existing remining permit with best professional judgment limitations and the Department determines that it is not feasible for a remining operator to re-establish baseline pollutant levels in accordance with the statistical procedures in this subchapter, pre-existing discharge limitations at the existing remining operation remain subject to baseline pollutant levels established during the original permit application.
§ 87.204. Application for authorization.
(a) An operator who requests authorization under this subchapter shall comply with the permit application requirements of Chapter 86 (relating to surface and underground coal mining: general) and Subchapters A and C—E, except as specifically modified by this subchapter. The operator shall also:
(1) Delineate on a map the proposed pollution abatement area, including the location of the pre-existing discharges.
(2) Provide a description of the hydrologic balance for the proposed pollution abatement area that includes:
(i) Results of a detailed water quality and quantity monitoring program, including seasonal variations, variations in response to precipitation events and modeled baseline pollution loads using this monitoring program.
(ii) Monitoring for flow, pH, alkalinity, acidity, total iron, total manganese, total aluminum, sulfates, total suspended solids and other water quality parameters the Department deems relevant.
(3) Provide a [description of the abatement plan that represents best technology and includes] pollution abatement plan which must:
(i) Describe the pollution abatement area.
(ii) Be designed to reduce the pollution load from pre-existing discharges and identify the selected best management practices (BMPs) to be used.
(iii) Describe the design specifications, construction specifications, maintenance schedules, criteria for monitoring and inspection, and expected performance of the BMPs.
(iv) Represent best technology and include:
[(i)] (A) Plans, cross-sections and schematic drawings describing the pollution abatement plan proposed to be implemented.
[(ii)] (B) A description and explanation of the range of abatement level that probably can be achieved, costs and each step in the proposed pollution abatement plan.
[(iii)] (C) A description of the standard of success for revegetation necessary to insure success of the pollution abatement plan.
(v) Provide a description of and information on the pre-existing discharges hydrogeologically connected to the remining area.
(4) Determine the baseline pollution load.
(5) Provide the background data that are the bases for the baseline pollution load. The baseline pollution load shall be reported in pounds per day.
(b) The operator seeking this authorization [shall] may continue the water quality and quantity monitoring program required by subsection (a)(2) after making the authorization request. The operator [shall] may submit the results of this continuing monitoring program to the Department on a monthly basis until a decision on the authorization request is made.
§ 87.205. Approval or denial.
(a) Authorization may not be granted under this subchapter unless the operator seeking the authorization affirmatively demonstrates to the satisfaction of the Department on the basis of information set forth in the application that:
(1) Neither the operator, nor an officer, principal shareholder, agent, partner, associate, parent corporation, contractor or subcontractor, or a related party as defined in [§ 86.63(1)] § 86.63(a)(1) (relating to compliance information) has either of the following:
(i) Legal responsibility or liability as an operator for treating the water pollution discharges from or on the proposed pollution abatement area.
(ii) Statutory responsibility or liability for reclaiming the proposed pollution abatement area.
(2) The proposed pollution abatement plan will result in significant reduction of the baseline pollution load and represents best technology.
(3) The land within the proposed pollution abatement area can be reclaimed.
(4) The surface mining operation on the proposed pollution abatement area will not cause additional ground water degradation.
(5) The standard of success for revegetation will be achieved. The standard of success for revegetation shall be at a minimum:
(i) A ground cover of living plants not less than can be supported by the best available topsoil or other suitable material in the reaffected area.
(ii) A ground cover no less than that existing before disturbance of the area by mining activities.
(iii) Adequate vegetation to control erosion. Vegetation may be no less than that necessary to insure the success of the pollution abatement plan.
* * * * * § 87.206. Operational requirements.
An operator who receives an authorization under this subchapter shall comply with the requirements of Chapter 86 (relating to surface and underground coal mining: general) and Subchapters A and C—E except as specifically modified by this subchapter. The operator shall also:
(1) Implement the approved water quality and quantity monitoring program for the pollution abatement area until the requirements of § 87.209 (relating to criteria and schedule for release of bonds on pollution abatement areas) are met. The monitoring program must conform to the following:
(i) Sampling shall be conducted on a monthly basis for the pre-existing discharges and should adequately represent the seasonal range in loading rates as well as the median loading rate from each pre-existing discharge or combination of discharges.
(ii) Results shall be submitted on a quarterly basis.
(iii) Data must include the flow measurements and loading calculations.
(2) Implement the approved pollution abatement plan.
[(3) Notify the Department immediately prior to the completion of each step of the abatement plan.
(4) Provide progress reports to the Department within 30 days after the completion of each step of the abatement program that include a notarized statement signed by the operator, and if required by the Department, a statement signed by the supervising engineer, that all work has been performed in accordance with the terms and conditions of the pollution abatement authorization, the approved maps, plans, profiles and specifications.]
(3) Notify the Department when more frequent sampling is required.
(i) Weekly sampling of the pre-existing discharges shall begin if any two consecutive monthly samples of pollution load at any of the monitoring points or hydrologic units exceed one or more of the triggers established by the baseline data.
(ii) Weekly sampling requirements shall continue until two consecutive weekly sample analyses indicate that all parameters which triggered weekly sampling have dropped below the trigger established by the baseline data.
§ 87.207. Treatment of discharges.
(a) Except for [preexisting] pre-existing discharges which are not encountered during mining or the implementation of the pollution abatement plan, the operator shall comply with § 87.102 (relating to hydrologic balance: effluent standards).
(b) [The] Except as provided in § 87.210(d) (relating to effluent limitations), the operator shall treat the [preexisting] pre-existing discharges which are not encountered during mining or implementation of the pollution abatement plan to comply with the effluent limitations established by best professional judgment. The effluent limitations established by best professional judgment may not be less than the baseline pollution load. If the baseline pollution load, when expressed as a concentration for a specific parameter, satisfies the effluent limitations at § 87.102 for that parameter, the operator shall treat the [preexisting] pre-existing discharge for that parameter to comply with either effluent limitations established by best professional judgment or the effluent limitations at § 87.102.
(c) For purposes of subsections (a) and (b), the term encountered may not be construed to mean diversions of surface water and shallow groundwater flow from areas undisturbed by the implementation of the pollution abatement plan which would otherwise drain into the affected area, so long as the diversions are designed, operated and maintained under § 87.105(b)—(g) (relating to hydrologic balance: diversions).
(d) An operator required to treat [preexisting] pre-existing discharges will be allowed to discontinue treating the discharges under subsection (b) when the operator affirmatively demonstrates to the Department's satisfaction that:
(1) The [preexisting] pre-existing discharges are meeting the effluent limitations established by subsection (b) as shown by groundwater and surface water monitoring conducted by the operator or the Department.
(2) Surface coal mining activities under the permit—including the pollution abatement area—are being or were conducted under the requirements of the permit and the authorization, and Chapter 86 (relating to surface and underground coal mining: general) and this chapter except as specifically modified by this subchapter.
(3) The operator has implemented each step of the pollution abatement plan as approved in the authorization.
(4) The operator did not cause or allow additional groundwater degradation by reaffecting the pollution abatement area.
(e) If after discontinuance of treatment of discharges under subsection (d) the discharges fail to meet the effluent limitations established by subsection (b), the operator shall reinstitute treatment of the discharges under subsection (b). An operator who reinstitutes treatment under this subsection will be allowed to discontinue treatment if the requirements of subsection (d) are met.
(f) Discontinuance of treatment under subsection (d) may not be deemed or construed to be or to authorize a release of bond under § 87.209 (relating to criteria and schedule for release of bonds on pollution abatement areas).
(g) If four consecutive weekly determinations of pollution load, as required under § 87.206(3)(i) (relating to operational requirements), exceed one or more triggers, the permittee shall notify the Department and begin treatment within 30 days of the fourth sample in accordance with the treatment limits established in the permit.
(h) If the Department determines, through analysis of any data submitted pursuant to the monitoring requirements or any data collected by the Department, that there has been pollution loading degradation at any of the monitoring points or hydrologic units, the Department will notify the permittee accordingly. The permittee shall begin treatment within 30 days in accordance with the treatment limits established in the permit.
(i) Any pre-existing pollutional discharge which is an encountered discharge shall be treated to the effluent limitations in the permit until the discharge is no longer encountered.
(j) For the purposes of determining applicable effluent limitations, a discharge will continue to be deemed to be an encountered discharge until the surface mining area which has been disturbed and which contributes to the discharge has been backfilled and regraded, and revegetation work has started.
§ 87.209. Criteria and schedule for release of bonds on pollution abatement areas.
* * * * * (b) The Department will release an additional amount of bond for the authorized pollution abatement area but retain an amount sufficient to cover the cost to the Department of reestablishing vegetation if completed by a third party if the operator demonstrates and the Department finds that:
(1) The operator has replaced the topsoil or material conserved under § 87.97(d) (relating to topsoil: removal), completed final grading, planting and established revegetation under the approved reclamation plan and achieved the standards of success for revegetation in § 87.205(a)(5) (relating to approval or denial).
(2) The operator has not caused or contributed to surface water pollution or groundwater degradation by reaffecting or mining the pollution abatement area.
(3) The operator has complied with one of the following:
(i) Achieved the actual improvement of the baseline pollution load described in the approved pollution abatement plan and shown by ground and surface water monitoring conducted by the permittee for the time provided in the pollution abatement plan after completion of backfilling, final grading, drainage control, topsoiling and establishment of revegetation to achieve the standard of success for revegetation in § 87.205(a)(5).
(ii) Achieved the following:
(A) At a minimum has not caused degradation of the baseline pollution load as shown by ground and surface water monitoring conducted by the operator or the Department for one of the following:
(I) For the 12 months prior to the date of application for bond release and until the bond release is approved under subsection (b), if backfilling, final grading, drainage control, topsoiling and establishment of revegetation to achieve the standard of success for revegetation in § 87.205(a)(5) have been completed.
(II) If treatment has been initiated at any time after initial bond release under subsection (a) and § 87.207(e) (relating to treatment of discharges), for 12 months from the discontinuance of treatment under § 87.207(d), if backfilling, final grading, drainage control, topsoiling and establishment of revegetation to achieve the standard of success for revegetation in § 87.205(a)(5) have been completed.
(B) Conducted the measures provided in the approved pollution abatement plan and additional measures specified by the Department in writing at the time of initial bond release under subsection (a) for the area requested for bond release.
* * * * * (Editor's Note: Sections 87.210—87.213 are new and printed in regular type to enhance readability.)
§ 87.210. Effluent limitations.
(a) Approval and incorporation into permit. The pollution abatement plan for the pollution abatement area must be approved by the Department and incorporated into the permit as an effluent limitation.
(b) Implementation of best management practices. The best management practices (BMPs) in the pollution abatement plan shall be implemented as specified in the plan.
(c) Pre-existing discharges.
(1) Except as provided in subsection (d), the following effluent limits apply to pre-existing discharges:
Parameter Effluent Limit Total Iron May not exceed baseline loadings (as determined by this subchapter). Total Manganese May not exceed baseline loadings (as determined by this subchapter). Acidity, Net May not exceed baseline loadings (as determined by this subchapter). Suspended Solids During remining and reclamation, may not exceed baseline loadings (as determined by this subchapter). Prior to bond release, the pre-existing discharge must meet the applicable standards for suspended solids or settleable solids in § 87.102 (relating to hydrologic balance: effluent standards). (2) A pre-existing discharge is exempt from meeting standards in § 87.102 for suspended solids and settleable solids when the Department determines that the standards are infeasible or impractical based on the site-specific conditions of soil, climate, topography, steep slopes or other baseline conditions provided that the operator demonstrates that significant reductions of suspended solids and settleable solids will be achieved through the incorporation of sediment control BMPs into the pollution abatement plan as required under subsection (a).
(d) In-stream requirements.
(1) If the Department determines that it is infeasible to collect samples for establishing the baseline pollutant levels under this subsection, and that remining will result in significant improvement that would not otherwise occur, the permit applicant may establish an in-stream baseline concentration at a suitable point downstream from the remining operation and the numeric effluent limitations in subsection (c)(1) do not apply.
(2) The in-stream baseline period must include, at a minimum, twice monthly monitoring for a minimum of a 1-year period and must adequately represent the seasonal range and median pollutant concentrations.
(3) Upon issuance of a surface mining permit, the operator shall continue, at a minimum, monthly monitoring of pollutant concentrations at the in-stream monitoring point referenced in paragraph (1), and make a determination as to whether or not there has been degradation of in-stream water quality.
(i) This determination shall be made on a quarterly basis and for each year defined as each consecutive 12-month period.
(ii) The operator is not required to treat individual pre-existing sources of pollution except as may be needed to maintain the in-stream baseline concentration.
(iii) Unless the operator can demonstrate to the satisfaction of the Department that the degradation was the result of factors that are not related to the remining, the operator shall treat one or more pre-existing pollutional discharges or undertake other pollution abatement measures to restore or improve the in-stream pollutant concentration to its baseline conditions.
(4) Pre-existing discharges for which it is infeasible to collect samples for determination of baseline pollutant levels include, but are not limited to:
(i) Discharges that exist as a diffuse groundwater flow that cannot be assessed by the collection of samples.
(ii) A base flow to a receiving stream that cannot be monitored separate from the receiving stream.
(iii) A discharge on a steep or hazardous slope that is inaccessible for sample collection.
(iv) A number of pre-existing discharges so extensive that monitoring of individual discharges is infeasible.
(5) When in-stream monitoring is not indicative of the impact of remining, the in-stream monitoring requirement may be waived by the Department. In-stream monitoring is not indicative of the impact of remining in circumstances including, but not limited to, the following:
(i) Remining sites in drainage areas exceeding 10 square miles.
(ii) Remining sites in watersheds where there are other influences on the in-stream water quality that make it impossible to establish the cause of water quality changes.
(iii) Remining sites where the Q7-10 stream flow is zero.
(e) Limits. Pollutants for which there are not effluent limitations established in § 87.102 may be eligible for limits established under this subchapter.
(f) Applicability of standards. Section 87.102 applies to a pre-existing discharge that is:
(1) Intercepted by surface mining activities.
(2) Commingled with waste streams from operational areas for the purposes of water treatment.
(g) Cessation of applicability of standards. Section 87.102 does not apply to a pre-existing discharge described in subsection (f) when the pre-existing discharge is no longer intercepted by surface mining activities or is no longer commingled with waste streams from operational areas for the purposes of water treatment.
(h) Bond release. The effluent limitations in this subchapter apply to pre-existing discharges until bond release under the procedures in Chapter 86 (relating to surface and underground coal mining: general).
§ 87.211. Baseline determination and compliance monitoring for pre-existing discharges at remining operations.
(a) The procedures in this section shall be used for determining site-specific baseline pollutant loadings, and for determining whether discharge loadings during coal remining operations have exceeded the baseline loading. A monthly (single-observation) procedure and an annual procedure shall be applied.
(b) At least one sample result per month shall be obtained for 12 months to characterize pollutant loadings for:
(1) Baseline determination.
(2) Each annual monitoring period. It is required that at least one sample be obtained per month for 12 months.
(c) Calculations described in this subchapter shall be applied to pollutant loadings.
(d) Each loading value shall be calculated as the product of a flow measurement and pollutant concentration taken on the same date at the same discharge sampling point using standard units of flow and concentration.
(e) If the baseline concentration in a baseline sample is below the daily maximum effluent limits established in § 87.102 (relating to hydrologic balance: effluent standards), the baseline sample concentration may be replaced with daily maximum effluent limit for the purposes of some of the statistical calculations in this subchapter.
(f) The substituted values should be used for all methods in this subchapter except for:
(1) The calculation of the interquartile range (R) in Method 1 for the annual trigger (Step 3).
(2) Method 2 for the single observation trigger (Step 3).
(g) The interquartile range (R) is calculated as the difference between the quartiles M-1 and M1; the values for quartiles M-1 and M1 should be calculated using actual loadings (based on measured concentrations) when they are used to calculate the interquartile range (R).
§ 87.212. Procedure for calculating and applying a single-observation (monthly) trigger.
(a) This section contains two alternative methods for calculating a single-observation trigger. One method must be proposed by the applicant to be approved and applied by the Department for a remining permit.
(b) Method 1 for calculating a single observation trigger (L) is accomplished by completing the following steps:
(1) Count the number of baseline observations taken for the pollutant of interest. Label this number n. To sufficiently characterize pollutant loadings during baseline determination and during each annual monitoring period, it is required that at least one sample result be obtained per month for 12 months.
(2) Order all baseline loading observations from lowest to highest. Let the lowest number (minimum) be x(1), the next lowest be x(2), and so forth until the highest number (maximum) is x(n).
(3) If fewer than 17 baseline observations were obtained, the single observation trigger (L) will equal the maximum of the baseline observations (x(n)).
(4) If at least 17 baseline observations were obtained, calculate the median (M) of all baseline observations. If n is odd, then M equals x
[Continued from previous Web Page] § 88.510. Effluent limitations.
(a) Approval and incorporation into permit. The pollution abatement plan for the pollution abatement area must be approved by the Department and incorporated into the permit as an effluent limitation.
(b) Implementation of best management practices. The best management practices (BMPs) in the pollution abatement plan shall be implemented as specified in the plan.
(c) Pre-existing discharges.
(1) Except as provided in subsection (d), the following effluent limits apply to pre-existing discharges:
Parameter Effluent Limit Total Iron May not exceed baseline loadings (as determined by this subchapter). Total Manganese May not exceed baseline loadings (as determined by this subchapter). Acidity, Net May not exceed baseline loadings (as determined by this subchapter). Suspended Solids During remining and reclamation, may not exceed baseline loadings (as determined by this subchapter). Prior to bond release, the pre-existing discharge must meet the applicable standards for suspended solids or settleable solids in § 88.92, § 88.187 or § 88.292 (relating to hydrologic balance: effluent standards). (2) A pre-existing discharge is exempt from meeting standards in § 88.92, § 88.187 or § 88.292 for suspended solids and settleable solids when the Department determines that the standards are infeasible or impractical based on the site-specific conditions of soil, climate, topography, steep slopes or other baseline conditions provided that the operator demonstrates that significant reductions of suspended solids and settleable solids will be achieved through the incorporation of sediment control BMPs into the pollution abatement plan as required under subsection (a).
(d) In-stream requirements.
(1) If the Department determines that it is infeasible to collect samples for establishing the baseline pollutant levels under this subsection, and that remining will result in significant improvement that would not otherwise occur, the permit applicant may establish an in-stream baseline concentration at a suitable point downstream from the remining operation and the numeric effluent limitations in subsection (c)(1) do not apply.
(2) The in-stream baseline period must include, at a minimum, twice monthly monitoring for a minimum of a 1-year period and must adequately represent the seasonal range and median pollutant concentrations.
(3) Upon issuance of a surface mining permit, the operator shall continue, at a minimum, monthly monitoring of pollutant concentrations at the in-stream monitoring point referenced in paragraph (1), and make a determination as to whether or not there has been de- gradation of in-stream water quality.
(i) This determination shall be made on a quarterly basis and for each year defined as each consecutive 12-month period.
(ii) The operator is not required to treat individual pre-existing sources of pollution except as may be needed to maintain the in-stream baseline concentration.
(iii) Unless the operator can demonstrate to the satisfaction of the Department that the degradation was the result of factors that are not related to the remining, the operator shall treat one or more pre-existing pollutional discharges or undertake other pollution abatement measures to restore or improve the in-stream pollutant concentration to its baseline conditions.
(4) Pre-existing discharges for which it is infeasible to collect samples for determination of baseline pollutant levels include, but are not limited to:
(i) Discharges that exist as a diffuse groundwater flow that cannot be assessed by the collection of samples.
(ii) A base flow to a receiving stream that cannot be monitored separate from the receiving stream.
(iii) A discharge on a steep or hazardous slope that is inaccessible for sample collection.
(iv) A number of pre-existing discharges so extensive that monitoring of individual discharges is infeasible.
(5) When in-stream monitoring is not indicative of the impact of remining, the in-stream monitoring requirement may be waived by the Department. In-stream monitoring is not indicative of the impact of remining in circumstances including, but not limited to, the following:
(i) Remining sites in drainage areas exceeding 10 square miles.
(ii) Remining sites in watersheds where there are other influences on the in-stream water quality that make it impossible to establish the cause of water quality changes.
(iii) Remining sites where the Q7-10 stream flow is zero.
(e) Limits. Pollutants for which there are not effluent limitations established in § 88.92, § 88.187 or § 88.292 may be eligible for limits established under this subchapter.
(f) Applicability of standards. Section 88.92, § 88.187 or § 88.292 applies to a pre-existing discharge that is:
(1) Intercepted by surface mining activities.
(2) Commingled with waste streams from operational areas for the purposes of water treatment.
(g) Cessation of applicability of standards. Section 88.92, § 88.187 or § 88.292 does not apply to a pre-existing discharge described in subsection (f) when the pre-existing discharge is no longer intercepted by surface mining activities or is no longer commingled with waste streams from operational areas for the purposes of water treatment.
(h) Bond release. The effluent limitations in this subchapter apply to pre-existing discharges until bond release under the procedures in Chapter 86 (relating to surface and underground coal mining: general).
§ 88.511. Baseline determination and compliance monitoring for pre-existing discharges at remining operations.
(a) The procedures in this section shall be used for determining site-specific baseline pollutant loadings, and for determining whether discharge loadings during coal remining operations have exceeded the baseline loading. A monthly (single-observation) procedure and an annual procedure shall be applied.
(b) At least one sample result per month shall be obtained for 12 months to characterize pollutant loadings for:
(1) Baseline determination.
(2) Each annual monitoring period. It is required that at least one sample be obtained per month for 12 months.
(c) Calculations described in this subchapter shall be applied to pollutant loadings.
(d) Each loading value shall be calculated as the product of a flow measurement and pollutant concentration taken on the same date at the same discharge sampling point using standard units of flow and concentration.
(e) If the baseline concentration in a baseline sample is below the daily maximum effluent limits established in § 88.92, § 88.187 or § 88.292 (relating to hydrologic balance: effluent standards), the baseline sample concentration may be replaced with daily maximum effluent limit for the purposes of some of the statistical calculations in this subchapter.
(f) The substituted values should be used for all methods in this subchapter except for:
(1) The calculation of the interquartile range (R) in Method 1 for the annual trigger (Step 3).
(2) Method 2 for the single observation trigger (Step 3).
(g) The interquartile range (R) is calculated as the difference between the quartiles M-1 and M1; the values for quartiles M-1 and M1 should be calculated using actual loadings (based on measured concentrations) when they are used to calculate the interquartile range (R).
§ 88.512. Procedure for calculating and applying a single-observation (monthly) trigger.
(a) This section contains two alternative methods for calculating a single-observation trigger. One method must be proposed by the applicant to be approved and applied by the Department for a remining permit.
(b) Method 1 for calculating a single observation trigger (L) is accomplished by completing the following steps:
(1) Count the number of baseline observations taken for the pollutant of interest. Label this number n. To sufficiently characterize pollutant loadings during baseline determination and during each annual monitoring period, it is required that at least one sample result be obtained per month for 12 months.
(2) Order all baseline loading observations from lowest to highest. Let the lowest number (minimum) be x(1), the next lowest be x(2), and so forth until the highest number (maximum) is x(n).
(3) If fewer than 17 baseline observations were obtained, the single observation trigger (L) will equal the maximum of the baseline observations (x(n)).
(4) If at least 17 baseline observations were obtained, calculate the median (M) of all baseline observations. If n is odd, then M equals x(n/2+1/2). If n is even, then M equals 0.5* (x(n/2) +x(n/2+1)).
(5) Next, calculate M1 as the median of the subset of observations that range from the calculated M to the maximum x(n); that is, calculate the median of all x larger than or equal to M.
(6) Next, calculate M2 as the median of the subset of observations that range from the calculated M1 to x(n); that is, calculate the median of all x larger than or equal to M1.
(7) Next, calculate M3 as the median of the subset of observations that range from the calculated M2 to x(n); that is, calculate the median of all x larger than or equal to M2.
(8) Finally, calculate the single observation trigger (L) as the median of the subset of observations that range from the calculated M3 to x(n).
(9) When subsetting the data for each of the steps in paragraphs (5)—(8), the subset should include all observations greater than or equal to the median calculated in the previous step. If the median calculated in the previous step is not an actual observation, it is not included in the new subset of observations. The new median value will then be calculated using the median procedure, based on whether the number of points in the subset is odd or even.
(c) The method for applying the single observation trigger (L) to determine when the baseline level has been exceeded is as follows:
(1) If two successive monthly monitoring observations both exceed L, immediately begin weekly monitoring for 4 weeks (four weekly samples).
(2) If three or fewer of the weekly observations exceed L, resume monthly monitoring.
(3) If all four weekly observations exceed L, the baseline pollution loading has been exceeded.
(d) Method 2 for calculating a single observation trigger (L) is accomplished by completing the following steps:
(1) Follow Method 1 in subsection (b) to obtain M1 (the third quartile, that is, the 75th percentile).
(2) Calculate M-1 as the median of the baseline data which are less than or equal to the sample median M.
(3) Calculate interquartile range, R = (M1 − M-1).
(4) Calculate the single observation trigger L as L = M1 + 3 * R.
(5) If two successive monthly monitoring observations both exceed L, immediately begin weekly monitoring for 4 weeks (four weekly samples).
(6) If three or fewer of the weekly observations exceed L, resume monthly monitoring.
(7) If all four weekly observations exceed L, the baseline pollution loading has been exceeded.
§ 88.513. Procedure for calculating and applying an annual trigger.
(a) This section contains two alternative methods for calculating the annual trigger. One method shall be proposed by the applicant to be approved and applied by the Department for a remining permit.
(b) Method 1 for calculating and applying an annual trigger (T) is accomplished by completing the following steps:
(1) Calculate M and M1 of the baseline loading data as described under Method 1 for the single observation trigger in § 88.512(b) (relating to procedure for calculating and applying a single-observation (monthly) trigger).
(2) Calculate M-1 as the median of the baseline data which are less than or equal to the sample median M.
(3) Calculate the interquartile range, R = (M1 − M-1).
(4) The annual trigger for baseline (Tb) is calculated as
Tb=M+(1.815*R)/SQRT(n)
where n is the number of baseline loading observations.
(5) To compare baseline loading data to observations from the annual monitoring period, repeat the steps in paragraphs (1)—(3) for the set of monitoring observations. Label the results of the calculations M` and R`. Let m be the number of monitoring observations.
(6) The subtle trigger (Tm) of the monitoring data is calculated as
Tm=M`-(1.815*R`)/SQRT(m)
(7) If Tm > Tb, the median loading of the monitoring observations has exceeded the baseline loading.
(c) Method 2 for calculating and applying an annual trigger (T) is accomplished by completing the following steps:
(1) Let n be the number of baseline loading observations taken, and let m be the number of monitoring loading observations taken. To sufficiently characterize pollutant loadings during baseline determination and during each annual monitoring period, it is required that at least one sample result be obtained per month for a period of 12 months.
(2) Order the combined baseline and monitoring observations from smallest to largest.
(3) Assign a rank to each observation based on the assigned order: the smallest observation will have rank 1, the next smallest will have rank 2 and so forth, up to the highest observation, which will have rank n + m. If two or more observations are tied (have the same value), then the average rank for those observations should be used.
(4) Sum all the assigned ranks of the n baseline observations, and let this sum be Sn.
(5) Obtain the critical value (C) from Table 1.
(6) Compare C to Sn. If Sn is less than C, then the monitoring loadings have exceeded the baseline loadings.
(7) Critical values for the Wilcoxon-Mann-Whitney test are as follows:
(i) When n and m are less than 21, use Table 1. To find the appropriate critical value, match column with correct n (number of baseline observations) to row with correct m (number of monitoring observations).
Table 1—Critical Values (C) of the Wilcoxon-Mann-Whitney Test (for a one-sided test at the 0.001 significance level)
m
n
10 11 12 13 14 15 16 17 18 19 20 10 66 79 93 109 125 142 160 179 199 220 243 11 68 82 96 112 128 145 164 183 204 225 248 12 70 84 99 115 131 149 168 188 209 231 253 13 73 87 102 118 135 153 172 192 214 236 259 14 75 89 104 121 138 157 176 197 218 241 265 15 77 91 107 124 142 161 180 201 223 246 270 16 79 94 110 127 145 164 185 206 228 251 276 17 81 96 113 130 149 168 189 211 233 257 281 18 83 99 116 134 152 172 193 215 238 262 287 19 85 101 119 137 156 176 197 220 243 268 293 20 88 104 121 140 160 180 202 224 248 273 299
(ii) When n or m is greater than 20 and there are few ties, calculate an approximate critical value using the following formula and round the result to the next larger integer. Let N = n + m.
Critical Value=0.5*n*(N+1)-3.0902*SQRT(n*M(N+1)/12)
(iii) When n or m is greater than 20 and there are many ties, calculate an approximate critical value using the following formula and round the result to the next larger integer. Let S be the sum of the squares of the ranks or average ranks of all N observations. Let N = n + m.
Critical Value=0.5*n*(N+1)-3.0902*SQRT(V)
In the preceding formula, calculate V using:
V=(n*m*S)/(N*(N-1)-(n*m*(N+1)2/(4*(N-1))
CHAPTER 90. COAL REFUSE DISPOSAL Subchapter F. COAL REFUSE DISPOSAL ACTIVITIES ON AREAS WITH [PREEXISTING] PRE-EXISTING POLLUTIONAL DISCHARGES § 90.302. Definitions.
The following words and terms, when used in this subchapter, have the following meanings, unless the context clearly indicates otherwise:
[Abatement plan—Any individual technique or combination of techniques, the implementation of which will result in reduction of the base line pollution load. Abatement techniques include, but are not limited to: Addition of alkaline material, special plans for managing toxic and acid-forming material, regrading, revegetation and relocating coal refuse to a coal refuse disposal area that includes systems to prevent adverse impacts to surface and groundwater and to prevent precipitation from contacting the coal refuse. ]
Actual improvement—The reduction of the baseline pollution load resulting from the implementation of the approved pollution abatement plan; except that any reduction of the baseline pollution load achieved by water treatment may not be considered as actual improvement provided that treatment approved by the Department of the coal refuse before, during or after placement in the coal refuse disposal area will not be considered to be water treatment.
Baseline pollution load—The characterization of the pollutional material being discharged from or on the pollution abatement area, described in terms of mass discharge for each parameter deemed relevant by the Department, including seasonal variations and variations in response to precipitation events. The Department will establish in each authorization the specific parameters it deems relevant for the baseline pollution load, including, at a minimum, iron and acid loadings.
Best professional judgment—The highest quality technical opinion forming the basis for the terms and conditions of the treatment level required after consideration of all reasonably available and pertinent data. The treatment levels shall be established by the Department under sections 301 and 402 of the Federal Clean Water [Pollution Control] Act (33 U.S.C.A. §§ 1311 and 1342).
Best technology—Measures and practices which will abate or ameliorate, to the maximum extent possible, discharges from or on the pollution abatement area. These measures include engineering, geochemical or other applicable practices.
Coal refuse disposal activities—
(i) The storage, dumping or disposal of any waste coal, rock, shale, slurry, culm, gob, boney, slate, clay, underground development wastes, coal processing wastes, excess soil and related materials, associated with or near a coal seam, that are either brought above ground or otherwise removed from a coal mine in the process of mining coal or are separated from coal during the cleaning or preparation operations.
(ii) The term does not include the removal or storage of overburden from surface mining activities.
Coal remining operation—A coal mining operation at a site on which coal mining was previously conducted and where the site has been abandoned or the performance bond has been forfeited.
Encountered discharge—
(i) A pre-existing discharge intercepted in the course of active surface mining activities, including, but not limited to, overburden removal, coal extraction and backfilling, or that occurs in the pit, any mining-related conveyance, sedimentation pond or treatment pond.
(ii) The term does not include diversions of surface water and shallow groundwater flow from areas undisturbed by the implementation of the pollution abatement plan which would otherwise drain into the affected area so long as they are designed, operated and maintained in accordance with § 90.104(b)—(g) (relating to hydrologic balance: diversions).
Excess soil and related material—
(i) Rock, clay or other material located immediately above or below a coal seam and which are extracted from a coal mine during the process of mining coal.
(ii) The term does not include topsoil or subsoil.
Pollution abatement area—
(i) The part of the permit area that is causing or contributing to the baseline pollution load.
(ii) The term includes adjacent and nearby areas that must be affected to bring about significant improvements of the baseline pollution load and may include the immediate locations of the discharges.
Pollution abatement plan—Best management practices (BMPs), including, but not limited to, the addition of alkaline material, special handling plans for managing toxic and acid forming material, regrading, revegetation and daylighting, that when implemented will result in reduction of the baseline pollution load.
Pre-existing discharge—
(i) Any discharge resulting from mining activities that have been abandoned prior to the time of a remining permit application.
(ii) The term includes a pre-existing discharge that is relocated as a result of the implementation BMPs in the pollution abatement plan.
Steep slope—
(i) Any slope, including abandoned mine land features, above 20 degrees or a lesser slope as may be defined by the Department after consideration of soil, climate and other characteristics of a region.
(ii) The term does not apply to situations in which an operator is mining on flat or gently rolling terrain, on which an occasional steep slope is encountered and through which the mining operation is to proceed, leaving a plain or predominantly flat area.
§ 90.303. Applicability.
* * * * * (b) Notwithstanding subsection (a), authorization will not be granted under this subchapter for repermitting under §§ 86.12 and 86.14 (relating to continued operation under interim permits; and permit application filing deadlines), permit renewals under § 86.55 (relating to permit renewals: general requirements) or permit transfers under § 86.56 (relating to transfer of permit).
(c) This subchapter applies to pre-existing discharges that are located within or are hydrologically connected to pollution abatement areas of a coal remining operation.
(d) When a coal remining operation seeks reissuance of an existing remining permit with best professional judgment limitations and the Department determines that it is not feasible for a remining operator to re-establish baseline pollutant levels in accordance with the statistical procedures in this subchapter, pre-existing discharge limitations at the existing remining operation remain subject to baseline pollutant levels established during the original permit application.
§ 90.304. Application for authorization.
(a) An operator who requests authorization under this subchapter shall comply with the permit application requirements of Chapter 86 (relating to surface and underground coal mining: general) and Subchapters A—D, except as specifically modified by this subchapter. The operator shall also:
(1) Delineate on a map the proposed pollution abatement area, including the location of the [preexisting] pre-existing discharges.
(2) Provide a description of the hydrologic balance for the proposed pollution abatement area that includes:
(i) Results of a detailed water quality and quantity monitoring program, including seasonal variations, variations in response to precipitation events and modeled baseline pollution loads using this monitoring program.
(ii) Monitoring for flow, pH, alkalinity, acidity, total iron, total manganese, total aluminum, sulfates, total suspended solids and other water quality parameters the Department deems relevant.
(3) Provide a [description of the abatement plan that represents best technology and includes the following] pollution abatement plan which must:
(i) Describe the pollution abatement area.
(ii) Be designed to reduce the pollution load from pre-existing discharges and must identify the selected best management practices (BMPs) to be used.
(iii) Describe the design specifications, construction specifications, maintenance schedules, criteria for monitoring and inspection, and expected performance of the BMPs.
(iv) Represent best technology and include:
[(i)] (A) Plans, cross-sections and schematic drawings describing the pollution abatement plan proposed to be implemented.
[(ii)] (B) A description and explanation of the range of abatement level that is anticipated to be achieved, costs and each step in the proposed pollution abatement plan.
[(iii)] (C) A description of the standard of success for revegetation necessary to ensure success of the pollution abatement plan.
(v) Provide a description of an information on the pre-existing discharges hydrogeologically connected to the remining area.
(4) Determine the baseline pollution load.
(5) Provide background data that are the bases for the baseline pollution load. The baseline pollution load shall be reported in pounds per day.
(b) The operator seeking this authorization [shall] may continue the water quality and quantity monitoring program required by subsection (a)(2) after making the authorization request. The operator [shall] may submit the results of this continuing monitoring program to the Department on a monthly basis until a decision on the authorization request is made.
§ 90.305. Application approval or denial.
(a) Authorization may not be granted under this subchapter unless the operator seeking the authorization affirmatively demonstrates the following to the satisfaction of the Department on the basis of information in the application:
(1) Neither the operator, nor an officer, principal shareholder, agent, partner, associate, parent corporation, subsidiary or affiliate, sister corporation, contractor or subcontractor, or a related party as defined in § 86.1 (relating to definitions) has either of the following:
(i) Legal responsibility or liability as an operator for treating the water pollution discharges from or on the proposed pollution abatement area.
(ii) Statutory responsibility or liability for reclaiming the proposed pollution abatement area.
(2) The proposed pollution abatement plan will result in significant reduction of the baseline pollution load and represents best technology.
(3) The land within the proposed pollution abatement area can be reclaimed.
(4) The coal refuse disposal activities on the proposed pollution abatement area will not cause additional surface water pollution or groundwater degradation.
(5) The standard of success for revegetation will be achieved. The standard of success for revegetation for sites previously reclaimed to the standards of this chapter and Chapters 87 and 88 (relating to surface mining of coal; and anthracite coal) shall be the standards set forth in § 90.159 (relating to revegetation: standards for successful revegetation). The standard of success for revegetation for sites not previously reclaimed to the standards of this chapter and Chapters 87 and 88 shall be, at a minimum, the following, provided the site is not a bond forfeiture site where the forfeited money paid into the fund is sufficient to reclaim the forfeited site to the applicable standards:
(i) A ground cover of living plants not less than can be supported by the best available topsoil or other suitable material in the reaffected area.
(ii) A ground cover no less than that existing before disturbance of the area by coal refuse disposal activities.
(iii) Adequate vegetation to control erosion. Vegetation may be no less than that necessary to ensure the success of the pollution abatement plan.
* * * * * § 90.306. Operational requirements.
[(a)] An operator who receives an authorization under this subchapter shall comply with Chapter 86 (relating to surface and underground coal mining: general) and Subchapters A—D except as specifically modified by this subchapter. The operator shall also:
(1) Implement the approved water quality and quantity monitoring program for the pollution abatement area until the requirements of § 90.309 (relating to criteria and schedule for release of bonds on pollution abatement areas) are met. The monitoring program must conform to the following:
(i) Sampling shall be conducted on a monthly basis for the pre-existing discharges and should adequately represent the seasonal range in loading rates as well as the median loading rate from each pre-existing discharge or combination of discharges.
(ii) Results shall be submitted on a quarterly basis.
(iii) Data must include the flow measurements and loading calculations.
(2) Implement the approved pollution abatement plan.
[(3) Notify the Department immediately prior to the completion of each step of the abatement plan.
(4) Provide a progress report to the Department within 30 days after the completion of each step of the abatement program that includes a statement signed by the operator, and if required by the Department, a statement signed by the supervising engineer, that all work has been performed in accordance with the terms and conditions of the pollution abatement authorization, the approved maps, plans, profiles and specifications.]
(3) Notify the Department when more frequent sampling is required.
(i) Weekly sampling of the pre-existing discharges shall begin if any two consecutive monthly samples of pollution load at any of the monitoring points or hydrologic units exceed one or more of the triggers established by the baseline data.
(ii) Weekly sampling requirements shall continue until two consecutive weekly sample analyses indicate that all parameters which triggered weekly sampling have dropped below the trigger established by the baseline data.
§ 90.307. Treatment of discharges.
(a) Except for [preexisting] pre-existing discharges that are not encountered during coal refuse disposal activities or the implementation of the pollution abatement plan, the operator shall comply with § 90.102 (relating to hydrologic balance: water quality standards, effluent limitations and best management practices). [281279]
(b) [The] Except as provided in § 90.310(d) (relating to effluent limitations), the operator shall treat the [preexisting] pre-existing discharges that are not encountered during coal refuse disposal activities or implementation of the pollution abatement plan to comply with the effluent limitations established by best professional judgment. The effluent limitations established by best professional judgment may not be less than the baseline pollution load. If the baseline pollution load, when expressed as a concentration for a specific parameter, satisfies the effluent limitation in § 90.102 for that parameter, the operator shall treat the [preexisting] pre-existing discharge for that parameter to comply with either effluent limitations established by best professional judgment or the effluent limitations in § 90.102.
(c) For purposes of subsections (a) and (b), the term encountered may not be construed to mean diversions of surface water and shallow groundwater flow from areas undisturbed by the implementation of the pollution abatement plan that would otherwise drain into the affected area, as long as the diversions are designed, operated and maintained under § 90.104(b)—(h) (relating to hydrologic balance: diversions).
(d) An operator required to treat [preexisting] pre-existing discharges will be allowed to discontinue treating the discharges under subsection (b) when the operator affirmatively demonstrates the following to the Department's satisfaction:
(1) The [preexisting] pre-existing discharges are meeting the effluent limitations established by subsection (b) as shown by groundwater and surface water monitoring conducted by the operator or the Department.
(2) Coal refuse disposal activities under the permit—including the pollution abatement area—are being or were conducted under the requirements of the permit and the authorization, and Chapter 86 (relating to surface and underground mining: general) and this chapter except as specifically modified by this subchapter.
(3) The operator has implemented each step of the pollution abatement plan as approved in the authorization.
(4) The operator did not cause or allow additional surface water pollution or groundwater degradation by reaffecting the pollution abatement area.
(e) If after discontinuance of treatment of discharges under subsection (d) the discharges fail to meet the effluent limitations established by subsection (b), the operator shall reinstitute treatment of the discharges under subsection (b). An operator who reinstitutes treatment under this subsection will be allowed to discontinue treatment if the requirements of subsection (d) are met.
(f) Discontinuance of treatment under subsection (d) may not be deemed or construed to be or to authorize a release of bond under § 90.309 (relating to criteria and schedule for release of bonds on pollution abatement areas).
(g) If four consecutive weekly determinations of pollution load, as required under § 90.306(3)(i) (relating to operational requirements), exceed one or more triggers, the permittee shall notify the Department and begin treatment within 30 days of the fourth sample in accordance with the treatment limits established in the permit.
(h) If the Department determines, through analysis of any data submitted pursuant to the monitoring requirements or any data collected by the Department, that there has been pollution loading degradation at any of the monitoring points or hydrologic units, the Department will notify the permittee accordingly. The permittee shall begin treatment within 30 days in accordance with the treatment limits established in the permit.
(i) Any pre-existing pollutional discharge which is an encountered discharge shall be treated to the effluent limitations in the permit until the discharge is no longer encountered.
(j) For the purposes of determining applicable effluent limitations, a discharge will continue to be deemed to be an encountered discharge until the surface mining area which has been disturbed and which contributes to the discharge has been backfilled and regraded, and revegetation work has started.
§ 90.309. Criteria and schedule for release of bonds on pollution abatement areas.
* * * * * (b) The Department will release up to an additional 35% of the amount of bond for the authorized pollution abatement area but retain an amount sufficient to cover the cost to the Department of reestablishing vegetation if completed by a third party if the operator demonstrates and the Department finds the following:
(1) The operator has replaced the topsoil or material conserved under § 90.97 (relating to topsoil: removal), completed final grading, planting and established revegetation under the approved reclamation plan and achieved the standards of success for revegetation in § 90.305(a)(5) (relating to application approval or denial).
(2) The operator has not caused or contributed to groundwater or surface water pollution by reaffecting the pollution abatement area.
(3) The operator has achieved the following standards:
(i) Achieved the actual improvement of the baseline pollution load described in the approved pollution abatement plan as shown by groundwater and surface water monitoring conducted by the permittee for the time provided in the pollution abatement plan after completion of backfilling, final grading, drainage control, topsoiling and establishment of revegetation to achieve the standard for success in § 90.305(a)(5).
(ii) Achieved the following:
(A) At a minimum has not caused degradation of the baseline pollution load as shown by groundwater and surface water monitoring conducted by the operator or the Department for one of the following:
(I) For 12 months from the date of initial bond release under subsection (a), if backfilling, final grading, drainage control, placement of impermeable cover, topsoiling and establishment of revegetation to achieve the standard of success for revegetation in § 90.305(a)(5) have been completed.
(II) If treatment has been initiated at any time after initial bond release under subsection (a) and § 90.307(e) (relating to treatment of discharges), for 12 months from the date of discontinuance of treatment under § 90.307(d), if backfilling, final grading, drainage control, placement of impermeable cover, topsoiling and establishment of revegetation to achieve the standard of success for revegetation in § 90.305(a)(5) have been completed.
(B) Conducted all the measures provided in the approved pollution abatement plan and additional measures specified by the Department in writing at the time of initial bond release under subsection (a) for the area requested for bond release.
* * * * * (Editor's Note: Sections 90.310—90.313 are new and printed in regular type to enhance readability.)
§ 90.310. Effluent limitations.
(a) Approval and incorporation into permit. The pollution abatement plan for the pollution abatement area must be approved by the Department and incorporated into the permit as an effluent limitation.
(b) Implementation of best management practices. The best management practices (BMPs) in the pollution abatement plan shall be implemented as specified in the plan.
(c) Pre-existing discharges.
(1) Except as provided in subsection (d), the following effluent limits apply to pre-existing discharges:
Parameter Effluent Limit Total Iron May not exceed baseline loadings (as determined by this subchapter). Total Manganese May not exceed baseline loadings (as determined by this subchapter). Acidity, Net May not exceed baseline loadings (as determined by this subchapter). Suspended Solids During remining and reclamation, may not exceed baseline loadings (as determined by this subchapter). Prior to bond release, the pre-existing discharge must meet the applicable standards for suspended solids or settleable solids in § 90.102 (relating to hydrologic balance: water quality standards, effluent limitations and best management practices). (2) A pre-existing discharge is exempt from meeting standards in § 90.102 for suspended solids and settleable solids when the Department determines that the standards are infeasible or impractical based on the site-specific conditions of soil, climate, topography, steep slopes or other baseline conditions provided that the operator demonstrates that significant reductions of suspended solids and settleable solids will be achieved through the incorporation of sediment control BMPs into the pollution abatement plan as required under subsection (a).
(d) In-stream requirements.
(1) If the Department determines that it is infeasible to collect samples for establishing the baseline pollutant levels under this subsection, and that remining will result in significant improvement that would not otherwise occur, the permit applicant may establish an in-stream baseline concentration at a suitable point downstream from the remining operation and the numeric effluent limitations in subsection (c)(1) do not apply.
(2) The in-stream baseline period must include, at a minimum, twice monthly monitoring for a minimum of a 1-year period and must adequately represent the seasonal range and median pollutant concentrations.
(3) Upon issuance of a surface mining permit, the operator shall continue, at a minimum, monthly monitoring of pollutant concentrations at the in-stream monitoring point referenced in paragraph (1), and make a determination as to whether or not there has been degradation of in-stream water quality.
(i) This determination shall be made on a quarterly basis and for each year defined as each consecutive 12-month period.
(ii) The operator is not required to treat individual pre-existing sources of pollution except as may be needed to maintain the in-stream baseline concentration.
(iii) Unless the operator can demonstrate to the satisfaction of the Department that the degradation was the result of factors that are not related to the remining, the operator shall treat one or more pre-existing pollutional discharges or undertake other pollution abatement measures to restore or improve the in-stream pollutant concentration to its baseline conditions.
(4) Pre-existing discharges for which it is infeasible to collect samples for determination of baseline pollutant levels include, but are not limited to:
(i) Discharges that exist as a diffuse groundwater flow that cannot be assessed by the collection of samples.
(ii) A base flow to a receiving stream that cannot be monitored separate from the receiving stream.
(iii) A discharge on a steep or hazardous slope that is inaccessible for sample collection.
(iv) A number of pre-existing discharges so extensive that monitoring of individual discharges is infeasible.
(5) When in-stream monitoring is not indicative of the impact of remining, the in-stream monitoring requirement may be waived by the Department. In-stream monitoring is not indicative of the impact of remining in circumstances including, but not limited to, the following:
(i) Remining sites in drainage areas exceeding 10 square miles.
(ii) Remining sites in watersheds where there are other influences on the in-stream water quality that make it impossible to establish the cause of water quality changes.
(iii) Remining sites where the Q7-10 stream flow is zero.
(e) Limits. Pollutants for which there are not effluent limitations established in § 90.102 may be eligible for limits established under this subchapter.
(f) Applicability of standards. Section 90.102 applies to a pre-existing discharge that is:
(1) Intercepted by surface mining activities.
(2) Commingled with waste streams from operational areas for the purposes of water treatment.
(g) Cessation of applicability of standards. Section 90.102 does not apply to a pre-existing discharge described in subsection (f) when the pre-existing discharge is no longer intercepted by surface mining activities or is no longer commingled with waste streams from operational areas for the purposes of water treatment.
(h) Bond release. The effluent limitations in this subchapter apply to pre-existing discharges until bond release under the procedures in Chapter 86 (relating to surface and underground coal mining: general).
§ 90.311. Baseline determination and compliance monitoring for pre-existing discharges at remining operations.
(a) The procedures in this section shall be used for determining site-specific baseline pollutant loadings, and for determining whether discharge loadings during coal remining operations have exceeded the baseline loading. A monthly (single-observation) procedure and an annual procedure shall be applied.
(b) At least one sample result per month shall be obtained for 12 months to characterize pollutant loadings for:
(1) Baseline determination.
(2) Each annual monitoring period. It is required that at least one sample be obtained per month for 12 months.
(c) Calculations described in this subchapter shall be applied to pollutant loadings.
(d) Each loading value shall be calculated as the product of a flow measurement and pollutant concentration taken on the same date at the same discharge sampling point using standard units of flow and concentration.
(e) If the baseline concentration in a baseline sample is below the daily maximum effluent limits established in § 90.102 (relating to hydrologic balance: water quality standards, effluent limitations and best management practices), the baseline sample concentration may be replaced with daily maximum effluent limit for the purposes of some of the statistical calculations in this subchapter.
(f) The substituted values should be used for all methods in this subchapter except for:
(1) The calculation of the interquartile range (R) in Method 1 for the annual trigger (Step 3).
(2) Method 2 for the single observation trigger (Step 3).
(g) The interquartile range (R) is calculated as the difference between the quartiles M-1 and M1; the values for quartiles M-1 and M1 should be calculated using actual loadings (based on measured concentrations) when they are used to calculate the interquartile range (R).
§ 90.312. Procedure for calculating and applying a single-observation (monthly) trigger.
(a) This section contains two alternative methods for calculating a single-observation trigger. One method must be proposed by the applicant to be approved and applied by the Department for a remining permit.
(b) Method 1 for calculating a single observation trigger (L) is accomplished by completing the following steps:
(1) Count the number of baseline observations taken for the pollutant of interest. Label this number n. To sufficiently characterize pollutant loadings during baseline determination and during each annual monitoring period, it is required that at least one sample result be obtained per month for 12 months.
(2) Order all baseline loading observations from lowest to highest. Let the lowest number (minimum) be x(1), the next lowest be x(2), and so forth until the highest number (maximum) is x(n).
(3) If fewer than 17 baseline observations were obtained, the single observation trigger (L) will equal the maximum of the baseline observations (x(n)).
(4) If at least 17 baseline observations were obtained, calculate the median (M) of all baseline observations. If n is odd, then M equals x(n/2+1/2). If n is even, then M equals 0.5* (x(n/2) +x(n/2+1)).
(5) Next, calculate M1 as the median of the subset of observations that range from the calculated M to the maximum x(n); that is, calculate the median of all x larger than or equal to M.
(6) Next, calculate M2 as the median of the subset of observations that range from the calculated M1 to x(n); that is, calculate the median of all x larger than or equal to M1.
(7) Next, calculate M3 as the median of the subset of observations that range from the calculated M2 to x(n); that is, calculate the median of all x larger than or equal to M2.
(8) Finally, calculate the single observation trigger (L) as the median of the subset of observations that range from the calculated M3 to x(n).
(9) When subsetting the data for each of the steps in paragraphs (5)—(8), the subset should include all observations greater than or equal to the median calculated in the previous step. If the median calculated in the previous step is not an actual observation, it is not included in the new subset of observations. The new median value will then be calculated using the median procedure, based on whether the number of points in the subset is odd or even.
(c) The method for applying the single observation trigger (L) to determine when the baseline level has been exceeded is as follows:
(1) If two successive monthly monitoring observations both exceed L, immediately begin weekly monitoring for 4 weeks (four weekly samples).
(2) If three or fewer of the weekly observations exceed L, resume monthly monitoring.
(3) If all four weekly observations exceed L, the baseline pollution loading has been exceeded.
(d) Method 2 for calculating a single observation trigger (L) is accomplished by completing the following steps:
(1) Follow Method 1 in subsection (b) to obtain M1 (the third quartile, that is, the 75th percentile).
(2) Calculate M-1 as the median of the baseline data which are less than or equal to the sample median M.
(3) Calculate interquartile range, R = (M1 − M-1).
(4) Calculate the single observation trigger L as L = M1 + 3 * R.
(5) If two successive monthly monitoring observations both exceed L, immediately begin weekly monitoring for 4 weeks (four weekly samples).
(6) If three or fewer of the weekly observations exceed L, resume monthly monitoring.
(7) If all four weekly observations exceed L, the baseline pollution loading has been exceeded.
§ 90.313. Procedure for calculating and applying an annual trigger.
(a) This section contains two alternative methods for calculating the annual trigger. One method shall be proposed by the applicant to be approved and applied by the Department for a remining permit.
(b) Method 1 for calculating and applying an annual trigger (T) is accomplished by completing the following steps:
(1) Calculate M and M1 of the baseline loading data as described under Method 1 for the single observation trigger in § 90.312(b) (relating to procedure for calculating and applying a single-observation (monthly) trigger).
(2) Calculate M-1 as the median of the baseline data which are less than or equal to the sample median M.
(3) Calculate the interquartile range, R = (M1 − M-1).
(4) The annual trigger for baseline (Tb) is calculated as
Tb=M+(1.815*R)/SQRT(n)
where n is the number of baseline loading observations.
(5) To compare baseline loading data to observations from the annual monitoring period, repeat the steps in paragraphs (1)—(3) for the set of monitoring observations. Label the results of the calculations M` and R`. Let m be the number of monitoring observations.
(6) The subtle trigger (Tm) of the monitoring data is calculated as
Tm=M`-(1.815*R`)/SQRT(m)
(7) If Tm > Tb, the median loading of the monitoring observations has exceeded the baseline loading.
(c) Method 2 for calculating and applying an annual trigger (T) is accomplished by completing the following steps:
(1) Let n be the number of baseline loading observations taken, and let m be the number of monitoring loading observations taken. To sufficiently characterize pollutant loadings during baseline determination and during each annual monitoring period, it is required that at least one sample result be obtained per month for a period of 12 months.
(2) Order the combined baseline and monitoring observations from smallest to largest.
(3) Assign a rank to each observation based on the assigned order: the smallest observation will have rank 1, the next smallest will have rank 2 and so forth, up to the highest observation, which will have rank n + m. If two or more observations are tied (have the same value), then the average rank for those observations should be used.
(4) Sum all the assigned ranks of the n baseline observations, and let this sum be Sn.
(5) Obtain the critical value (C) from Table 1.
(6) Compare C to Sn. If Sn is less than C, then the monitoring loadings have exceeded the baseline loadings.
(7) Critical values for the Wilcoxon-Mann-Whitney test are as follows:
(i) When n and m are less than 21, use Table 1. To find the appropriate critical value, match column with correct n (number of baseline observations) to row with correct m (number of monitoring observations).
Table 1—Critical Values (C) of the Wilcoxon-Mann-Whitney Test (for a one-sided test at the 0.001 significance level)
m
n
10 11 12 13 14 15 16 17 18 19 20 10 66 79 93 109 125 142 160 179 199 220 243 11 68 82 96 112 128 145 164 183 204 225 248 12 70 84 99 115 131 149 168 188 209 231 253 13 73 87 102 118 135 153 172 192 214 236 259 14 75 89 104 121 138 157 176 197 218 241 265 15 77 91 107 124 142 161 180 201 223 246 270 16 79 94 110 127 145 164 185 206 228 251 276 17 81 96 113 130 149 168 189 211 233 257 281 18 83 99 116 134 152 172 193 215 238 262 287 19 85 101 119 137 156 176 197 220 243 268 293 20 88 104 121 140 160 180 202 224 248 273 299 (ii) When n or m is greater than 20 and there are few ties, calculate an approximate critical value using the following formula and round the result to the next larger integer. Let N = n + m.
Critical Value=0.5*n*(N+1)-3.0902*SQRT(n*M(N+1)/12)
(iii) When n or m is greater than 20 and there are many ties, calculate an approximate critical value using the following formula and round the result to the next larger integer. Let S be the sum of the squares of the ranks or average ranks of all N observations. Let N = n + m.
Critical Value=0.5*n*(N+1)-3.0902*SQRT(V)
In the preceding formula, calculate V using:
V=(n*m*S)/(N*(N-1)-(n*m*(N+1)2/(4*(N-1))
[Pa.B. Doc. No. 15-1758. Filed for public inspection October 2, 2015, 9:00 a.m.]
Document Information
- PA Codes:
- 25 Pa. Code § 87.202
25 Pa. Code § 87.203
25 Pa. Code § 87.204
25 Pa. Code § 87.205
25 Pa. Code § 87.206
25 Pa. Code § 87.207
25 Pa. Code § 87.209
25 Pa. Code § 87.210
25 Pa. Code § 87.211
25 Pa. Code § 87.212
25 Pa. Code § 88.510
25 Pa. Code § 88.511
25 Pa. Code § 88.512
25 Pa. Code § 88.513
25 Pa. Code § 90.302
25 Pa. Code § 90.303
25 Pa. Code § 90.304
25 Pa. Code § 90.305
25 Pa. Code § 90.306
25 Pa. Code § 90.307
25 Pa. Code § 90.309
25 Pa. Code § 90.310
25 Pa. Code § 90.311
25 Pa. Code § 90.312
25 Pa. Code § 90.313