\    UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
     o                    REGION
                       1650 Arch Street
                Philadelphia, Pennsylvania 19103-2029
                  Decision Rationale
            Total Maximum Daily Loads
   For Acid Mine Drainage Affected Segments
                York Run Watershed
           Fayette County, Pennsylvania
                                     Signed
                                    Jon M. Capacasa, Director
                                    Water Protection Division

                                    Date: 6/11/2008
Printed on 100% recycled/recyclable paper with 100% post-consumer fiber and process chlorine free.
               Customer Service Hotline: 1-800-438-2474

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                                  Decision Rationale
                             Total Maximum Daily Loads
            York Run Watershed for Acid Mine Drainage Affected Segments
                             Fayette County, Pennsylvania
I.  Introduction

       The Clean Water Act (CWA) requires that Total Maximum Daily Loads (TMDLs) be
developed for those waterbodies identified as impaired by the state where technology-based and
other controls will not provide for attainment of water quality standards.  A TMDL is a
determination of the amount of a pollutant from point, nonpoint, and natural background sources,
including a Margin of Safety (MOS) that may be discharged to a waterbody without exceeding
water quality standards.

       The Pennsylvania Department of Environmental Protection (PADEP) Bureau of
Watershed Management submitted the York Run  Watershed TMDL, Fayette County, For Acid
Mine Drainage Affected Segments (TMDL Report), dated April 3, 2008, to the U.S.
Environmental Protection Agency (EPA) for final Agency review on April 7, 2008. This report
includes the TMDLs for the three primary metals associated with acid mine drainage (AMD)
(i.e., iron,  manganese, aluminum and pH) and addresses one segment on Pennsylvania's 1996
Section 303(d) List of impaired  waters.

       EPA's rationale is based on the TMDL Report and information contained in the
attachments. EPA's review determined that the TMDL meets the following seven regulatory
requirements pursuant to 40 CFR Part 130:

       1.  The TMDL is designed to implement  applicable water quality standards.
       2.  The TMDL includes a total allowable load as well as individual wasteload allocations
          (WLAs) and load allocations (LAs).
       3.  The TMDL considers the impacts  of background pollutant contributions.
       4.  The TMDL considers critical environmental conditions.
       5.  The TMDL considers seasonal environmental variations.
       6.  The TMDL includes a MOS.
       7.  The TMDL has been subject to public participation.

II.  Summary

       Table 1 presents the 1996,  1998, 2002, 2004 and 2006 Section 303(d) listing information
for the impaired segment first listed in 1996.  Pennsylvania's 1996, 1998, 2002, and 2004
Section 303(d) Lists were approved by the Environmental Protection Agency (EPA). The 1996
Section 303(d) List provides the basis for measuring progress under the 1997 lawsuit settlement
of American Littoral Society and Public Interest  Group of Pennsylvania v. EPA.

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Table 1. 303(d) Listed Segments - State Water Plan (SWP) Subbasin: 19G
HUC: 05020005 Lower Monogahela River
Year
1996
1998
2002
2002
2004
2004
2006
2006
2006
2006
2006
2006
2006
2006
2006
2006
2006
2006
2006
2006
2006
2006
Miles
1.3
1.32
1.3
1.8
1.3
1.8
1.33
1.75
5.44
1.47
1.25
0.38
2.76
1.2
0.63
0.91
0.4
2.92
1.18
1.75
1.04
1.08
1.07
0.95
Designated
Use
*
*
*
*
*
*
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Aquatic Life
Assess-
ment
ID
*
*
*
*
*
*
7621
10063
11663
11663
11663
11663
11663
11663
11663
11663
11663
11663
11663
11663
11663
11663
11663
11663
Segment
ID
4921
4921
4921
990102-
1105-TVP
4921
990102-
1105-TVP
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
DEP
Stream
Code
41360
41360
41360
41360
41360
41360
41360
41362
41363
41364
41365
41366
41367
41368
41369
41370
41371
41372
41373
41374
41375
41376
Stream
Name
York Run
York Run
York Run
York Run
York Run
York Run
York Run
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
York Run,
Unt
Desig-
nated
Use
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
WWF
Data
Source
305(b)
Report
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
SWMP
Source
RE
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
AMD
EPA
305(b)
Cause
Code
Metals
Metals
Metals
Metals
pH
Metals
Metals
PH
Metals
Metals
pH
Metals
Metals
Metals
Metals
Metals
Metals
Metals
Metals
Metals
Metals
Metals
Metals
Metals
Metals
Metals
Metals

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HUC: 05020005 Lower Monogahela River
Year
2006
2006
2006
Miles
1.92
1.24
0.84
Designated
Use
Aquatic Life
Aquatic Life
Aquatic Life
Assess-
ment
ID
11663
11663
11663
Segment
ID
*
*
*
DEP
Stream
Code
41377
41378
41379
Stream
Name
York Run,
Unt
York Run,
Unt
York Run,
Unt
Desig-
nated
Use
WWF
WWF
WWF
Data
Source
SWMP
SWMP
SWMP
Source
AMD
AMD
AMD
EPA
305(b)
Cause
Code
Metals
Metals
Metals
Resource Extraction=RE
Warm Water Fish = WWF
Surface Water Monitoring Program = SWMP
Abandoned Mine Drainage = AMD
See Attachment D, Excerpts Justifying Changes Between the 1996, 1998, and 2002 Section 303(d) Lists and the 2004 and 2006
Integrated Water Quality Report. The use designations for the stream segments in this TMDL can be found in PA Title 25
Chapter 93.

       See Attachment D of the TMDL Report, Excerpts Justifying Changes Between the 1996,
1998, 2002, Section 303(d) Lists and the Integrated Report Lists for 2004 and 2006. The use
designations for the stream segments in this TMDL can be found in PA Title 25, Chapter 93.9v,
Section IV.

       In 1997, PADEP began utilizing the Statewide Surface Waters Assessment Protocol to
assess Pennsylvania's waters. This protocol is a modification of EPA's 1989 Rapid
Bioassessment Protocol II and provides for a more consistent approach to conducting biological
assessments than previously used methods.  The biological assessments are used to determine
which waters are impaired and should be included on the State's Section 303(d) List.

       The TMDLs in this report were developed using a statistical procedure to ensure that
water quality criteria are met 99% of the time as required by Pennsylvania's water quality
standards at Pennsylvania Code Title 25, Chapter 96.3c.  Table 3 of the TMDL Report lists the
TMDLs for the York Run Watershed, addressing metals and pH in the stream segments listed as
PADEP stream code 41360.

       TMDLs are defined as the summation of the point source WLAs plus the summation of
the nonpoint source LAs plus a MOS and are often shown as follows:

                           TMDL = £WLAs + £LAs + MOS

       The TMDL is a written plan and analysis established to ensure that a waterbody will
attain and maintain applicable water quality standards.  The TMDL is a scientifically-based
strategy which considers current and foreseeable conditions, utilizes the best available data, and
accounts for uncertainty with the inclusion of a MOS value.  Since conditions, available data,
and the understanding of natural processes can change more than anticipated by the MOS, there
exists the option of refining the TMDL for resubmittal to EPA.
III. Background

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       The York Run Watershed is located in southwestern Pennsylvania, occupying the
western portions of Fayette County in Nicholson and Georges Townships. The watershed is
located on the Smithfield 7.5' quadrangle U.S. Geologic Survey map. The area within the
watershed is approximately 16 square miles.  York Run drains to Georges Creek, intersecting
Georges Creek about 2 miles southwest of the town of Smithfield.

       Geologically, the watershed is on the western flank of the Uniontown Syncline.  The axis
of the syncline trends northeast and southwest and is located one mile east of the main branch of
York Run.  The flanks of the syncline are very gently dipping.  The watershed is in the Low
Plateau Physiographic Province.

       Land uses within the York Run Watershed include agricultural, abandoned mine lands,
large abandoned coke operations, rural residential properties, and small communities. The towns
in the watershed (from the headwaters to the confluence with Georges Creek) include:  Amend,
Chadville, Collier, Shoaf, York Run, Bowood, Smithfield, and Woodside. No large housing
developments or projects are expected in this watershed at this time.

       The entire Monogahela Group make up the exposed geologic formations found in this
watershed.  Most of the  watershed area has been greatly disturbed by surface mining, deep
mining, coal refuse piles, and coke operations. The entire northern half of the watershed has
abandoned underground Pittsburgh coal seam mines beneath it; there are dozens of Pittsburgh
coal seam surface mines also. There are also dozens of surface mines on the Redstone and
Sewickley Coal seams as well as Sewickley underground mines in this watershed, and a handful
of Uniontown coal seam and Waynesburg coal seam surface mines in the northern edge of the
watershed.

       The Surface Mining Control and Reclamation Act of 1977 (SMCRA, Public Law 95-87)
and its subsequent revisions were enacted to establish a nationwide program to, among other
things, protect the beneficial uses of land or water resources, protect public health and safety
from the adverse effects of current surface coal mining operations, and promote the reclamation
of mined areas left without adequate reclamation prior to August 3, 1977.  SMCRA requires a
surface mining permit for the development of new, previously mined, or abandoned sites for the
purpose of surface mining.  Permittees are required to post a performance bond that will be
sufficient to ensure the completion of reclamation requirements by the regulatory authority in the
event that the applicant  forfeits. Mines that ceased operating by the effective date of SMCRA
(often called "pre-law" mines) are not subject to the requirements of SMCRA.

       York Run was on the 1996 Section 303(d) List of impaired waters and counts toward the
twelfth year (2009) TMDL milestone commitment under the requirements of the 1997 TMDL
lawsuit settlement agreement.  The twelfth year milestone is the development of TMDLs, or
delisting, for all remaining waters listed as impaired by AMD impacts on Pennsylvania's 1996
Section 303(d) List of impaired waters.

Computational Procedure

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       The TMDLs were developed using a statistical procedure to ensure that water quality
criteria are met 99% of the time as required by Pennsylvania's water quality standards. A two-
step approach was used for the TMDL analysis of impaired stream segments.

       The first step used a statistical method for determining the allowable instream
concentration at the point of interest necessary to meet water quality standards. An allowable
long-term average instream concentration was determined at each sample point for metals and
acidity.  The analysis was performed using Monte Carlo simulation to determine the necessary
long-term average concentration needed to attain water quality criteria 99% of the time, and the
simulation was run assuming the dataset was log normally distributed. Using @RISK2, each
pollutant source was evaluated separately by performing 5,000 iterations of the model where
each iteration was independent of all other iterations. This procedure was used to determine the
required percent reduction that would allow the water quality criteria to be met instream at least
99% of the time.  A second simulation that multiplied the percent reduction by the sampled value
was run to ensure that criteria were met 99% of the time. The mean value from this dataset
represents the long-term average concentration that needs to be met to achieve water quality
standards.

       The second step was a mass balance of the loads as they passed through the watershed.
Loads at these points were computed based on average flow. Once the allowable concentration
and load for each pollutant was determined, mass-balance accounting was performed starting at
the top of the watershed and working downstream in sequence. This mass balance or load
tracking through the watershed utilized the change in measured loads from sample location to
sample location as a guide for expected changes in the allowable loads.

       The existing and allowable long-term average loads were computed using the mean
concentration from @RISK multiplied by the average flow.  The loads were computed based on
average flow and should not be taken out of the context for which they are intended. They are
intended to depict how the pollutants affect the watershed and where the sources and sinks are
located spatially in the watershed.  A critical flow was not identified, and the reductions
specified in this TMDL apply at all flow conditions.

       In addition to the above analysis, the WLAs for the National Pollutant Discharge
Elimination System (NPDES) permitted pit water treatment ponds were determined. Typically,
surface mining operations include an open pit where overburden material has been removed to
access the underlying coal, and this pit can accumulate water primarily through direct
precipitation and surface runoff. The pit water is pumped to a nearby treatment pond where it is
treated to the level necessary to meet effluent limitations.  However, precipitation events allow
intermittent discharges from the treatment pond. If accurate flow data are available for a
treatment pond, they can be used to quantify the WLA by multiplying  the flow by the best
available technology (BAT) effluent limitations for treatment ponds.  However, these flow data
are typically not available. Alternatively, PADEP calculated a total average flow for the water
       2
       @RISK - Risk Analysis and Simulation Add-in for Microsoft Excel, Palisade Corporation, Newfield,
NY.

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draining to the pit using average annual precipitation, the area of the pit, and a runoff factor.
Utilizing this value and BAT treatment pond effluent limits, the WLAs were determined.
IV. Discussions of Regulatory Requirements

       EPA has determined that these TMDLs are consistent with statutory and regulatory
requirements and EPA policy and guidance.

1.  The TMDLs are designed to implement the applicable water quality standards.

       Water quality standards are state regulations that define the water quality goals of a
waterbody.  Standards are comprised of three components: (1) designated uses; (2) criteria
necessary to protect those uses; and (3) antidegradation provisions that prevent the degradation
of water quality. York Run has been designated by Pennsylvania as a cold water fishery with
criteria to protect the aquatic life use, and the designation can be found at Pennsylvania Title 25
§93.9v.  To protect the designated use as well as the existing use, the water quality criteria
shown in Table 2 apply to all evaluated segments. The table includes the instream numeric
criterion for each parameter and any associated  specifications.

                       Table 2.  Applicable Water Quality Criteria
Parameter
Aluminum (Al)
Iron (Fe)
Manganese (Mn)
pH
Criterion
Value (mg/1)
0.75
1.50
0.30
1.00
6.0-9.0
Duration
Maximum
30-day Average
Maximum
Maximum
Inclusive
Total Recoverable/
Dissolved
Total Recoverable
Total Recoverable
Dissolved
Total Recoverable
N/A
       Pennsylvania Title 25 §96.3c requires that water quality criteria be achieved at least
99% of the time, and TMDLs expressed as long-term average concentrations are expected to
meet these requirements.  That is, the statistical Monte Carlo simulation used to develop TMDL
WLAs and LAs for each parameter resulted in a determination that any required percent
pollutant reduction would assure that the water quality criteria would be met instream at least
99% of the time. The Monte Carlo analysis performed 5,000 iterations of the model where each
iteration was independent of all other iterations and the dataset was assumed to be log normally
distributed.

       EPA finds that these TMDLs will attain and maintain the applicable narrative and
numeric water quality standards.

       The pH values shown in Table 2 were used as the endpoints for these TMDLs.  In the
case of freestone streams with little or no buffering capacity, the allowable TMDL endpoint for
pH may be the natural background water quality, and these values can be as low as 5.4
(Pennsylvania Fish and Boat Commission). However, PADEP chose to set the pH standard
between 6.0 to 9.0, inclusive, which is presumed to be met when the net alkalinity is maintained
above zero.  This presumption is based on the relationship between net alkalinity and pH, on

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which PADEP based its methodology to addressing pH in the watershed (see the York Run
Watershed TMDL Report, Attachment B). A summary of the methodology is presented as
follows:

       The parameter of pH, a measurement of hydrogen ion acidity presented as a negative
logarithm of effective hydrogen ion concentration, is not conducive to standard statistics.
Additionally, pH does not measure latent acidity that can be produced from the hydrolysis of
metals. PADEP has been using an alternate approach to address the stream impairments noted
on the Section 303(d) List due to pH. Because the concentration of acidity in a stream is
partially dependent upon metals, it is extremely difficult to predict the exact pH values which
would result from treatment of AMD. Therefore, net alkalinity will be used to evaluate pH in
these TMDL calculations.  This methodology assures that the standard for pH will be met
because net alkalinity is able to measure the reduction of acidity.  When acidity in a stream is
neutralized or is restored to natural levels, pH will be acceptable (>6.0). Therefore, the
measured instream alkalinity at the point of evaluation in the stream will serve as the goal for
reducing  total acidity at that point. The methodology that is used  to calculate the required
alkalinity (and therefore pH) is the same as that used for other parameters such as iron,
aluminum, and manganese that have numeric water quality criteria.  EPA finds this approach to
addressing pH to be reasonable.

       PADEP also has an alkalinity standard. Alkalinity (of a minimum 20 mg/1 calcium
carbonate except where natural conditions are less) is related but not identical to pH. Alkalinity
is a measure of the buffering capacity of the water.  Adequate buffering prevents large swings in
pH with additions of small amounts of acid.  Although many of the AMD impacted streams are
naturally low in alkalinity,  available monitoring data do not always include upstream waters not
impacted by AMD.  As PADEP does not list waters for inadequate alkalinity, TMDLs are not
being developed for alkalinity; but PADEP should monitor the waters for alkalinity and if, after
these TMDLs are implemented, alkalinity is less than 20 mg/1 or natural conditions, PADEP
should list the waters for alkalinity and develop TMDLs.

2.  The TMDLs include a total allowable  load as well as individual wasteload allocations and
   load allocations.

       For purposes of these TMDLs only, point sources are identified as permitted discharge
points or discharges having responsible parties, and nonpoint sources are identified as any
pollution sources that are not point sources. Abandoned mine lands were treated in the
allocations as nonpoint sources.  As such, the discharges associated with these land uses were
assigned  LAs (as opposed to WLAs). The decision to assign LAs to abandoned mine lands does
not reflect any determination by EPA as to whether there are un-permitted point source
discharges within these land uses.  In addition,  by approving these TMDLs with mine drainage
discharges treated as LAs, EPA is not determining that these discharges are exempt from  NPDES
permitting requirements.

       To determine the WLAs for the NPDES permitted pit water treatment ponds, PADEP
first calculated a total average flow for the water draining to the pit using average annual
precipitation, the area of the pit, and a runoff factor.  The WLAs were then calculated using this

                                           7

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value and the BAT treatment pond effluent limits and were included in the mass balance along
with the LAs.

       Once PADEP determined the allowable concentration and load for each pollutant, a mass
balance accounting was performed starting at the top of the watershed and working downstream
in sequence. Load tracking through the watershed utilizes the change in measured loads from
sample location to sample location as a guide for expected changes in the allowable loads.

       PADEP used two basic rules for the load tracking between two ends of a stream segment:
(1) if the measured upstream loads are less than the downstream loads, it is indicative that there
is an increase in load between the points being evaluated, and no instream processes are
assumed; and (2) if the sum of the measured loads from the upstream points is greater than the
measured load  at the downstream point, it is indicative that there is a loss of instream load
between the points, and the ratio of the decrease shall be applied to the allowable load being
tracked from the upstream point.

       Tracking loads through the watershed provides a picture of how the pollutants are
affecting the watershed  based on the available information.  The analysis is performed to ensure
that water quality standards will be met at all points in the stream. EPA finds this approach
reasonable.

       Table 3 presents a summary of the allowable loads, LAs, and WLAs for the York Run
Watershed.
                     Table 3. York Run Watershed Summary Table
Parameter
Existing
Load
(Ibs/day)
TMDL
Allowable
Load
(Ibs/day)
WLA
(Ibs/day)
LA
(Ibs/day)
NFS Load
Reduction
(Ibs/day)
NFS %
Reduction
YorklO - Headwaters of York Run near town of York Run
Aluminum (Ibs/day)
Iron (Ibs/day)
Manganese(lbs/day)
Acidity (Ibs/day)
152.56
3258.81
266.91
0
24.67
95.59
75.64
0
1.96
7.91
5.25
.
22.71
87.68
70.39
NA
127.89
3163.22
191.27
NA
84%
97%
72%
NA
York09 - York Run near Sleepy Hollow Rd.
Aluminum (Ibs/day)
Iron (Ibs/day)
Manganese(lbs/day)
Acidity (Ibs/day)
200.83
3075.46
289.40
0
31.73
101.33
76.20
0
1.68
6.78
4.50
0
30.05
94.55
71.70
NA
41.21
0.00
21.93
NA
57%*
0%*
23%*
NA
YorkOS - York Run near York Run Junction
Aluminum (Ibs/day)
Iron (Ibs/day)
Manganese(lbs/day)
Acidity (Ibs/day)
389.51
2892.40
311.50
0
27.06
102.89
82.85
0
1.68
6.78
4.50
0
25.38
96.11
78.35
NA
193.35
0.00
15.45
NA
88%*
0%*
16%*
NA
YorkO? - Unnamed Tributary 41370 to York Run
Aluminum (Ibs/day)
817.66
7.79
0
7.79
809.87
99%

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Parameter
Iron (Ibs/day)
Manganese(lbs/day)
Acidity (Ibs/day)
Existing
Load
(Ibs/day)
373.36
73.19
7017.24
TMDL
Allowable
Load
(Ibs/day)
13.71
13.15
0.00
WLA
(Ibs/day)
0
0
0
LA
(Ibs/day)
13.71
13.15
0.00
NFS Load
Reduction
(Ibs/day)
359.65
60.04
7017.24
NFS %
Reduction
97%
83%
100%
York06 - York Run at Church Street
Aluminum (Ibs/day)
Iron (Ibs/day)
Manganese(lbs/day)
Acidity (Ibs/day)
1119.28
3399.63
408.19
5335.06
55.53
158.92
94.75
671.06
1.68
6.78
4.50
0
53.85
152.14
90.25
676.06
0.00
91.55
24.75
0.00
0%*
37%*
21%*
0%*
YorkOS - York Run at Smithfield Rd
Aluminum (Ibs/day)
Iron (Ibs/day)
Manganese(lbs/day)
Acidity (Ibs/day)
1356.18
3435.55
453.21
6978.17
74.91
183.52
105.65
415.49
1.68
6.78
4.50
0
73.23
176.74
101.15
415.49
217.52
11.32
34.12
1898.68
75%*
6%*
25%*
82%*
York04- Unnamed Tributary 41362 to York Run
Aluminum (Ibs/day)
Iron (Ibs/day)
Manganese(lbs/day)
Acidity (Ibs/day)
56.21
5.73
7.36
111.91
1.65
3.80
3.49
14.93
0
0
0
0
1.65
3.80
3.49
14.93
54.56
1.93
3.87
96.98
97%
34%
53%
87%
York02 - Unnamed Tributary 41361 to York Run
Aluminum (Ibs/day)
Iron (Ibs/day)
Manganese(lbs/day)
Acidity (Ibs/day)
0.13
0.44
0.08
0
0.13
0.44
0.08
0
0
0
0
0
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
YorkOl - York Run at Mouth
Aluminum (Ibs/day)
Iron (Ibs/day)
Manganese(lbs/day)
Acidity (Ibs/day)
1511.81
3878.08
486.20
6871.26
87.93
171.90
125.76
444.25
1.68
6.78
4.50
0
86.25
165.12
121.26
444.25
88.05
452.22
9.01
0.00
50%*
73%*
7%*
0%*
NA = not applicable ND = not detected
* Takes into account load reductions from upstream sources.
Numbers in italics are set aside for future mining operations.

       PADEP allocated to nonpoint sources and point sources, as there currently is one active
surface mine in the area.  TJ. Hill Coal Company operates the Burd Mine (PA0202061) with
seven permitted outfalls, located in Georges Township, Fayette County.  In addition to the active
mining operations, the summary table includes wasteload allocations for 15 future mining sites.
Where there are active mining operations, Federal regulations require that point source permitted
effluent limitations be water quality-based subsequent to TMDL development and approval. It
should be noted that technology-based permit limits may be converted to water quality based
limits according to EPA's Technical Support Document For Water Quality-based Toxics
Control, March  1991, recommendations. In addition, PA Title 25, Chapter 96, Section 96.4d
requires that WLAs serve as the basis for determination of permit limits for point source
discharges regulated under Chapter 92 (relating to NPDES permitting, monitoring, and

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compliance).  Therefore, no new mining may be permitted within the watershed without
reallocation of the TMDL. Additionally, no required reductions of permit limits are necessary at
this time, as all necessary reductions have been assigned to nonpoint sources.

          Table 4. Wasteload Allocations at Burd Operation (PA0202061)
Parameter
Monthly Avg.
Allowable Cone.
(Mg/1)
Average Flow
(MGD)
Allowable Load
(Lbs/Day)
Outfall No. 006
Al
Fe
Mn
0.75
3
2
0.045
0.045
0.045
0.28
1.13
0.75
Outfall No. 007
Al
Fe
Mn
0.75
3
2
0.045
0.045
0.045
0.28
1.13
0.75
Outfall No. 8
Al
Fe
Mn
0.75
3
2
0.045
0.045
0.045
0.28
1.13
0.75
Outfall No. 9
Al
Fe
Mn
0.75
3
2
0.045
0.045
0.045
0.28
1.13
0.75
Outfall No. 10
Al
Fe
Mn
0.75
3
2
0.045
0.045
0.045
0.28
1.13
0.75
Outfall No. 11
Al
Fe
Mn
0.75
3
2
0.045
0.045
0.045
0.28
1.13
0.75
Outfall No. 12
Al
Fe
Mn
0.75
3
2
0.045
0.045
0.045
0.28
1.13
0.75
3.  The TMDLs consider the impacts of background pollutant contributions.

       The TMDLs were developed using instream data, which account for existing background
conditions.
4.  The TMDLs consider critical environmental conditions.

       The reductions specified in these TMDLs apply at all flow conditions.  A critical flow
condition was not identified from the available data.
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5.  The TMDLs consider seasonal environmental variations.

       The dataset included data points from all seasons, thereby accounting for seasonal
variation implicitly.

6.  The TMDLs include a Margin of Safety.

       The CWA and Federal regulations require TMDLs to include a MOS to take into account
any lack of knowledge concerning the relationship between effluent limitations and water
quality. EPA guidance suggests two approaches to satisfy the MOS requirement. First, it can be
met implicitly by using conservative model assumptions to develop the allocations. Alternately,
it can be met explicitly by allocating a portion of the allowable load to the MOS.

       PADEP used an implicit MOS in these TMDLs by assuming that the treated instream
concentration variability was the same as the untreated stream's concentration variability. This
is a more conservative assumption than the general assumption that a treated discharge has less
variability than an untreated discharge. By retaining variability in the treated discharge, a lower
average concentration is required to meet water quality criteria 99% of the time than if the
variability of the treated discharge is reduced.

       Additionally, calculations were performed using a daily average  for iron rather than the
30-day average, thereby, incorporating a MOS.

7.  The TMDLs have been subject to public participation.

       Public notice of the draft TMDL was published in the Pennsylvania Bulletin and The Herald
Standard on January 9, 2008, to foster public comment on the allowable loads calculated. The
public  comment period on this TMDL was open January 9, 2008 to March 19, 2008.  A public
meeting was held on January 23, 2008, at the Fayette County Health Center to discuss the proposed
TMDL.

       Although not specifically stated in the TMDL Report, PADEP routinely posts the
approved TMDL Reports on their web site:  www.dep.state.pa.us/watermanagement_apps/tmdl/.

V. Discussion of Reasonable Assurance

       The Recommendations section of the TMDL Report highlights what can be done in the
York Run Watershed to eliminate or treat pollutant sources.  Aside from PADEP's primary
efforts  to improve water quality in the York Run Watershed through reclamation of abandoned
mine lands and through the NPDES permit program, additional opportunities for reasonable
assurance exist.  PADEP expects that activities such as research conducted by its Bureau of
Abandoned Mine Reclamation,  funding from EPA's §319 grant program, and Pennsylvania's
Growing Greener program will help remedy abandoned mine drainage impacts.  PADEP also has
in place an initiative that aims to maximize reclamation of Pennsylvania's abandoned mineral
extraction lands. Through Reclaim PA, Pennsylvania's goal  is to accomplish complete

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reclamation of abandoned mine lands and plugging of orphaned wells. Pennsylvania strives to
achieve this objective through legislative and policy land management efforts and activities
described in the TMDL Report.

       The Georges Creek Clearwater Cooperative Initiative is a watershed organization
interested in the Georges Creek Watershed, of which York Run is a tributary. It is recommended
that agencies support local interests to implement remediation projects in the watershed to abate
effects of AMD pollution.
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