-------
System 2. This system assumes a new source using a clarifier to
treat the preparation plant discharge prior to 100 percent recy-
cle. A separate pond designed to contain the runoff from a
10-year, 24-hour storm would be used for associated area runoff.
The associated area and pond would be ditched to divert undis-
turbed area runoff from associated area runoff. Figure VIII-30
is a schematic of this system.
Capital Costs
System 1. This system, as shown in Figure VIII-29, is applied to
new sites where all treatment facilities are constructed when the
preparation plant is constructed. A slurry pond for the prepara-
tion plant wastewater would be installed and a pump station for
100 percent recycle of the treated water required. Associated
area runoff would be segregated from the undisturbed area. The
items required for this system include:
Figure
Preparation plant slurry pond with dikes VIII-13 St VIII-22
Recycle pump station VIII-24
Associated area segregation by ditch VIII-23
Pond for associated area runoff VIII-13
The figure numbers next to the items can be used to determine the
capital costs.
System 2. This system, as shown in Figure VIII-30, is applied to
new sites when a clarifier is used to treat the preparation plant
discharge. The items required for this system include:
Figure
Clarifier VIII-31
Sludge dewatering VIII-17
Recycle pump Station VIII-24
Associated area segregation from undisturbed
area by ditch VIII-23
Pond for associated area runoff VIII-13 & VIII-22
The figure numbers next to the items can be used to determine the
capital costs.
337
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Annual Costs
For both new source systems, the annual costs can be derived from
the same annual cost curves presented for existing sources.
POST MINING DISCHARGES
Operation and maintenance costs to treat post mining discharges
through bond release are presented in this section. (Note: this
treatment is already required by OSM.)
General Assumptions Used
In determining the treatment costs, five assumptions were made:
1. No capital charges are included. It is assumed
facilities are fully depreciated by the time of mine closure.
2. No "typical" pond size could be assumed. Ponds range
from "no pond" to 21 acre-feet in storage.
3. A "typical" lime dosage is 300 mg/1.
4. Operation and maintenance and energy costs for lime
feeding are not sensitive to lime dosage rates and are assumed
constant.
5. Sludge pumping energy costs are less than five percent
of the total operation and maintenance costs. Therefore, energy
costs for varying sludge rates are masked by the total operation
and maintenance cost.
Reclamation Areas
These costs apply only to surface mines. The costs include sedi-
mentation structures for treating the runoff from areas under
reclamation through release from the applicable reclamation bond.
For this subcategory, treatment is for the control of settleable
solids and pH.
Assumptions
In determing the treatment costs, two assumptions were neces-
sary:
1. Since OSM requires treatment facilities for areas under
reclamation to meet BPT limitations, no capital costs result from
these requirements.
2. Lime for pH control should not be required for dis-
charges covered in the reclamation phase since no acid wastewater
340
-------
should be formed at these facilities. Again, this has been veri-
fied by an Agency study of reclamation areas.
Operation and Maintenance Costs
The costs associated with areas under reclamation include opera-
tion and maintenance costs for sedimentation ponds and mainte-
nance costs for runoff control with earth dikes or drainage
ditches. The cost curves for these areas are identical to
figures previously presented, but are repeated here for conveni-
ence. Figure VIII-32 presents operation and maintenance costs
for sedimentation ponds. The capital.cost of the pond was found
in Figure VIII-13. The maintenance costs for runoff control with
earth dikes or drainage ditches are given in Figure VIII-33.
Supporting information and assumptions for developing these
figures may be obtained in Appendix A.
Alkaline Underground Mines
Only settling ponds are considered for costing. No clarifiers
have been included because few alkaline deep mines employ clari-
fiers for wastewater treatment. The annual operation and main-
tenance cost curve for wastewater treatment with settling ponds
was presented in Figure VIII-32. The annual maintenance cost
curve for earth dike or drainage ditch runoff control was illus-
trated in Figure VIII-33. Supporting information and assumptions
for developing these figures may be found in Appendix A.
Acid Underground Mines
Two treatment systems are considered for costing. The first
system includes settling ponds, lime addition equipment, and
aeration equipment. The second system includes clarifiers, lime
addition equipment, and aeration equipment.
Costs Associated with Both Settling Pond and Clarifier Systems.
The annual costs associated with both systems may be obtained
from Figures VIII-34, VIII-35, and VIII-36. Included in the cost
curves of Figure VIII-36 is the cost of hydrated lime at $65 per
ton. Supporting information and assumptions for developing these
figures may be found in Appendix A.
Costs Associated Only with the Settling Pond System. Operation
and maintenance costs were illustrated in Figures VIII-32 and
VIII-33. The total operation and maintenance costs for the
sedimentation pond system (including sedimentation ponds, lime
addition and aeration) are determined by adding the costs from
Figures VIII-32 and VIII-33 to the costs obtained from Figures
VIII-34, VIII-35, and VIII-36.
341
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8,000
6,000
4,000
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STORAGE VOLUME IN ACRE FEET
21
24
27
Figure VIII-32
SEDIMENTATION POND OPERATION AND MAINTENANCE
ANNUAL 'COST CURVE FOR POST MINING DISCHARGES
342
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POST MINING DISCHARGE LIME ADDITION CHEMICAL COST CURVES
FORL'.UNDERGROUND COAL MINE ACID WASTEWATER TREATMENT WITH
SEDIMENT PONDS OR CLARIFIERS
344
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Figure VIII-35
POST MINING DISCHARGE LIME FEED FACILITIES OPERATION AND
MAINTENANCE ANNUAL COST CURVES FOR UNDERGROUND COAL MINE
ACID WASTEWATER TREATMENT WITH
SEDIMENTATION PONDS OR CLARIFIERS
345
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Figure VIII-36
POST MINING DISCHARGE AERATION OPERATION
AND MAINTENANCE ANNUAL COST CURVE FOR UNDERGROUND COAL
MINE ACID WASTEWATER TREATMENT WITH SEDIMENTATION PONDS
OR CLARIFIERS
346
-------
Costs Associated Only with the Clarifier System. The clarifier
and sludge pumping operation and maintenance costs are presented
in Figure VIII-37. To obtain the total operation and maintenance
costs for the clarifier system (including clarifiers, lime addi-
tion, and aeration), add the costs from Figure VIII-37 to the
costs obtained from Figures VIII-34, VIII-35, and VIII-36.
GENERAL ASSUMPTIONS UNDERLYING CAPITAL COSTS FOR ALL
SUBCATEGORIES
Building Costs
Buildings will be required to house chemical and polymer feed
equipment, as well as the controls for the treatment systems.
The cost estimates were prepared by including various subcate-
gories, i.e., costs for concrete, superstructure, plumbing, sani-
tation, and lighting. The electrical and control panel costs as
well as laboratory facilities and office equipment are included
in the building costs. These costs are included in the capital
cost curves for each of the treatment levels.
Piping
The type of piping costed for each treatment system is carbon
steel. Pipe diameters were sized based on six to seven feet per
second flow velocity. The costs for piping were based on
up-to-date pipe cost quotations and a factor of 100 percent was
added to this cost to account for fittings, flanges, hangers,
excavation, and backfilling as required.
Electrical and Instrumentation
The electrical and instrumentation costs for the treatment levels
were estimated at 30 percent of the cost of the applicable equip-
ment .
Power Supply for Mine Water Treatment
Operation of the equipment associated with the three candidate
levels of BAT treatment may require additional electric power at
the site. This power can be supplied by either running a power
line from an accessible trunk line or power source, or by using
diesel powered generator units. The worst case would probably be
to run a high voltage trunk line from a generating facility long
distances to the wastewater treatment facility. In addition to
the capital cost for power line construction, associated costs
for metering, transformers and secondary lines would be required.
In order to provide information on the costs for running power
lines, two supply voltage levels were assumed: 480 volts and
347
-------
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DESIGN FLOW IN MGD
Figure VIII-37
AFTER MINE CLOSURE CLARIFIER MECHANISM AND
SLUDGE PUMPING OPERATION AND MAINTENANCE
ANNUAL COST CURVE FOR UNDERGROUND COAL MINE
ACID WASTEWATER TREATMENT WITH CLARIFIERS
348
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4.16 kilovolts. It was then assumed that the practical break-
point on transmission distance would be between 500 to 1,000 feet
for 480 volts. Distances approaching 1,000 feet and longer would
require a feeder of 4.16 kV. Table VIII-4 has been prepared to
present approximate cost for power lines. If the distance from
the source and user and the load in kilowatts (kW) is known, the
table can be used to obtain the power line costs. These prices
include installation, poles, wire, insulators and crossarms for
480 volts and also includes a power center at the user containing
a high voltage incoming section with necessary protection discon-
necting devices, transformer (4.16 kV/480V) and secondary side
circuit breaker.
In cases where trunk or secondary lines are not readily avail-
able, it may be advantageous to operate diesel engine generator
units. The range of approximate power requirements for the three
candidate levels of BAT is from 5 kw at the lowest flow rate,
level 2, to 150 kw for the highest flow rate, level 4. An eco-
nomic tradeoff exists between the relatively low capital cost for
a diesel unit and the relatively low maintenance and operating
costs of a long distance trunk line system. Table VTII-5 pro-
vides cost estimates for diesel generator units for a range of
power requirements. The costs presented in Table VIII-5 include
an ICC approved weather-housed trailer with controls, cables,
battery muffler system, alternator, control panel, silencer,
diesel engine, and generator. Capital costs for electric power
supply do not include land requirements and are not included in
the capital cost curves presented for the various treatment
levels, due to the highly site-specific nature of these costs.
No extensive power requirements are necessary at the preparation
plants since power is already available for production equipment.
Land
Additional land may have to be purchased in order to comply with
BAT/NSPS. This cost is difficult to estimate on a general basis
since the information received during the mine visits indicated
that the cost can vary from a few hundred dollars to $40,000 per
acre. If additional land is required, land costs must be added
to the capital cost obtained from the treatment level system
curves. The amount of land needed for proposed BAT alternatives
is presented on an individual equipment basis for each level of
treatment suggested (1). A value of $4,000 per acre is assumed
to represent a reasonable cost and is recommended for use unless
a different value is known for a particular site.
Equipment
The equipment costs included in this subsection are for polymer
addition equipment, pump stations, mixing tanks, clarifiers,
gravity filters, and water storage tanks. This encompasses
349
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Table VIII-3
COST OF OVERHEAD ELECTRICAL DISTRIBUTION SYSTEMS
480V System
Distance
ft
250
500
Distance
ft
1000
1500
2000
2500
3000
3500
4000
4500
5000
100
$1500
$3200
100
$19,000
$20,400
$22,000
$23,500
$25,000
$26,600
$28,000
$29,800
$31,300
L 0
200
$1900
$4900
L
200
$19,000
$20,400
$22,000
$23,500
$25,000
$27,700
$29,400
$31,200
$32,900
A D - K
300
$2100
$5500
4.16 KV
0 A D -
300
$20,000
$21,400
$23,000
$25,300
$26,000
$28,700
$32,400
$34,400
$36,400
W
400
$2500
$6700
System
K W
400
$23,000
$25,000
$26,600
$29,600
$31,500
$36,300
$38,600
$41,000
$49,700
500
$3100
*
500
$23,000
$25,000
$25,600
$29,600
$31,500
$36,300
$38,600
$41,000
$49,700
Notes
*Voltage drop
excessive
Notes
Power center
costs included
M ii
M n
ii n
M II
II II
II 11
II M
It II
Reference (2)
350
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Table VIII-4
CAPITAL COSTS FOR DIESEL GENERATOR SETS*
Generator Type Power Requirement (Kv) Cost (1000$)
Air-Cooled 10 11
Air-Cooled 30 16
Radiator-Cooled 55 20
Radiator-Cooled 100 24
Radiator-Cooled 150 30
Reference (4)
351
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equipment required for all three treatment levels. Cost esti-
mates for installation, engineering, administration, and con-
tingencies are also included.
Polymer Addition Equipment. Capital costs of polymer addition
equipment are relatively insensitive to mine drainage flow rates
according to vendor price quotations. Below 750,000 gpd the
installed capital cost was estimated at $30,000 and above 750,000
gpd the cost estimate was $40,000. These costs include a mixing
tank, feed pump, transfer pump, storage tank, an enclosure, and
an electric heater. Costs for the enclosure and heater were
additional to those given by the vendors of the polymer equip-
ment. The costs for these two items were estimated at $10,000
for the enclosure and $6,000 for the heater.
Pump Stations. Installed capital costs for pump stations include
a 3/8 inch steel structure, pumps and motors, piping, valves,
fittings, structural steel (stairwells, ladders, ancillary equip-
ment), electrical equipment and instrumentation. Two pumps were
assumed for all flow rates up to 3.0 mgd; above this flow rate
three pumps were used.
Mixing Tanks. The cost for the mixing tanks used in level 3
includes three steel tanks and skids, three mixers, nine slide
gates, structural steel, aeration systems (blowers and piping),
electrical equipment, and instrumentation.
Flocculatpr-Clarifiers. A flocculator-clarifier composed of a
steel tank (1/4 inch thick) in concrete base, the internal
flocculation and sludge scraping mechanisms, structural steel,
slide gates, sludge pumps and motors, electrical equipment and
instrumentation.
Gravity Granular Media Filters. The equipment included with
gravity filters is composed of a concrete pad, a backwash water
storage tank, piping connections, filter cells, media, underdrain
system, electrical equipment and instrumentation. The filters
were sized based on a flux rate of 10 gpm/ft^.
Installation. Installation is defined here to include all ser-
vices, activities, and materials required to implement the
described wastewater treatment systems. Many factors affect the
magnitude of this cost including wage rates, in-house or con-
tracted construction work and site dependent conditions. The
installation costs are included in capital cost estimates pre-
sented in this section.
Engineering, Administration and Contingencies. The costs asso-
ciated with taxes,insurance,engineering,administration, and
contingencies are computed as 25 percent of the installed cost of
facilities and equipment.
352
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GENERAL ASSUMPTIONS UNDERLYING ANNUAL COSTS FOR ALL SUBCATEGORIES
The annual costs computed for each of the treatment systems
suggested for BAT are categorized as follows:
Amortization
Operation and Maintenance
Labor
Materials and Supplies
Chemicals
Energy
Amortization
The annual depreciation and capital costs are computed based on
using the capital recovery factor:
AC - (II)(CRF)
where
AC = annual cost
II = initial investment
CRF - capital recovery factor = (r)(r+l)n/((l+r)n-l)
r = annual interest rate
n = useful life in years.
An interest rate of 10 percent was used in all cases. The
expected life differs for civil construction work and mechanical
and electrical equipment items and their installation, i.e., the
expected life for civil construction work is 30 years and 10
years for installed mechanical and electrical equipment. No
residual or salvage value is assumed. Based on these assump-
tions, the general multipliers (AC/II) compute as follows:
CRF(civil)30 " 0-10608
CRF(mech. & elec.)io = 0.16275
Operation and Maintenance
General. Operating time of the systems costed is assumed to be
for 24 hours per day, 365 days per year.
353
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Operating and Maintenance Personnel. Personnel costs are based
on an annual rate of $28,000.
Maintenance Materials. The materials necessary for performing
yearly maintenance activities are estimated at three percent of
the capital cost of the facilities including the contingency
item.
Chemicals. The chemicals costed for use in any of the levels of
treatment are polymer and lime. The polymer cost is estimated at
$2.00 per pound, lime estimated at $65/ton. Yearly costs will
vary according to the dosage level used in the treatment system.
A polymer dosage rate of two ppm was selected for computing
annual polymer costs in each applicable system.
Power Costs. Electricity costs are based on auxiliary power
requirements in terms of kilowatts and 8,760 hours per year of
operation. The cost per kilowatt hour is estimated at $0.03 (2).
SLUDGE HANDLING AND ASSOCIATED COSTS
The sludge produced in the treatment of mine drainage, prep-
aration plant effluent and pond sedimentation can be handled by
various methods. Three methods which may be used and are
considered in this report are: sludge lagoons, trucking of
dewatered sludge to disposal site and trucking of undewatered
sludge to disposal site.
Sludge Lagoons
The sludge lagoon would require construction of a lagoon and
pumping the sludge from the treatment facility to the lagoon.
Available data for lime neutralization indicates that sludge
production is about 10 percent by volume of the incoming flow
(solids concentration of two percent) (1). This sludge would
compact in a lagoon to 10 percent solids which equates to three
percent by volume of the incoming flow treated. To arrive at a
cost it is assumed that the sludge storage requirements would be
for an estimated 10 year life of the mine. The cost curves for
capital and yearly cost for the sludge lagooning approach are
shown in Figure VIII-38.
Haulage of Dewatered Sludge
The method of dewatering sludge considered here consists of pump-
ing the sludge to a thickener. The thickened sludge is then
dewatered by vacuum filters before hauling to disposal. It is
assumed that this system will increase the solids loading in the
sludge to about 25 percent. The cost curves for capital and
yearly costs, as well as energy requirements for this dewatering,
are shown in Figure VIII-39. The estimated cost for hauling
354
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100 c
I I I I I I I! I I I I I I I I I I I I I I
CAPITAL
COST
YEARLY
COST
I I I I I I I I I I I I I I II I I I I M II
DESIGN FLOW IN M.G.D.
Figure VIII-38
MINE DRAINAGE TREATMENT
SLUDGE LAGOON VERSUS DESIGN FLOW
355
-------
I I I I I I 14-
0.001
10
DESIGN FLOW IN M.G.D.
Figure VIII-39
MINE DRAINAGE TREATMENT
SLUDGE DEWATERING VERSUS DESIGN FLOW
COST AND ENERGY CURVES
356
-------
dewatered sludge to disposal sites, based on a one round trip
mile, is presented in Figure VIII-40. To maintain a uniform cost
basis, this curve is a plot of design flow in mgd versus cost in
thousands of dollars.
Haulage of Undevatered Sludge
The final sludge handling approach is to haul the sludge to dis-
posal sites without dewatering. This involved pumping the sludge
at about two percent solids to a tank truck and then hauling to a
disposal site where it is lagooned or pumped into a bore hole.
The trucking cost for hauling this sludge, based on a round trip
mile, is also presented in Figure VIII-40. Assumptions and cost
criteria for sludge handling are based on information provided in
reference (2).
To calculate the cost of land, Figure VIII-41 presents the sludge
lagoon area required versus mine drainage flow rates.
REGIONAL SPECIFICITY FOR COSTS
Variations in capital and annualized costs are dependent on the
region in which the treatment facility is located. These
differences are due to such factors as soil type, precipitation,
topography, and vegetation. Cost multipliers have been prepared
to reflect these cost differences and are presented in Table
VIII-6 in the column entitled "Basic Capital Cost Multiplier."
The development of these multipliers is presented in reference
(5).
Before using these multipliers for a particular region, the
extent to which certain costs have already been absorbed in
establishing BPT facilities should be determined; this may
require a certain degree of downward multiplier adjustment in the
cost. Items which affect the accuracy of these basic multipliers
are previously built-in access roads, clearing and grubbing, etc.
The development of the Capital Cost Multiplier Adjusted to Civil
Works was based on the premise that the multiplier is only appli-
cable to that portion of the capital cost which is associated
with excavation, backfilling, and concrete placement. The
assumed contribution which these items provided in the overall
construction investment is 40 percent. Thus, the basic multi-
pliers are adjusted to 40 percent of their original value (5).
Table VIII-6 also presents the formula which demonstrates the
application of the adjusted capital cost multiplier to yearly
costs. Regional cost multipliers for yearly cost would apply
only to that portion of the yearly cost associated with the civil
works part of the facilities, such as the civil works portion of
the amortization and associated charges.
357
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DESIGN FLOW IN M.G.D.
10
Figure VIII-40
YEARLY COST OF ONE ROUND TRIP MILE
OF SLUDGE HAULING VERSUS DESIGN FLOW
MINE DRAINAGE TREATMENT
358
-------
io c
DESIGN FLOW IN M.G.D.
Figure VIII-41
SLUDGE LAGOON - AREA REQUIRED VERSUS DESIGN FLOW
MINE DRAINAGE TREATMENT
359
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Table VIII-5
COST MULTIPLIERS FOR COAL MINING REGIONS IN THE UNITED STATES
Region
Northern Appalachia
Central Appalachia
South Appalachia
Midwest
Central W«st
Gulf
Northern Great Plains
Rockies
Southwest
Basic Capital
Cost Multiplier
Capital Cost Multi-
plier Adjusted to
Civil Works
1.8
1.8
1.7
1.3
1.2
1.0
1.0
1.9
1.65
1.32
1.32
1.28
1.12
1.08
1.0
1.0
1.36
1.26
NOTES:
To obtain the adjusted yearly cost for a region where the capital
cost multiplier is greater than, one use the following formula:
Adjusted Yearly Capital
Yearly = Cost from - Recovery x
Cost Curve Factor
Reference (5)
Yearly
Co s t from
Curve
Capital
x 1 - Cost
Multiplier
360
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Examples of regionally specific cost determination procedures are
provided in the cost manual (1).
NON-WATER QUALITY ASPECTS
The effects of the candidate technologies on air pollution, solid
waste generation, and energy requirements have been considered.
The latter aspect has been addressed in earlier subsections, and
will not be repeated.
Air Pollution
Imposition of regulations based on any of the candidate technol-
ogies in any subcategory will not create any additional air
pollution.
Solid Waste Generation
The neutralization and aeration of acid mine drainage results in
a suspension of ferric hydroxide, other metal hydroxides, and
unreacted reagents (lime) in an aqueous solution of salts com-
posed largely of sulfates. This suspended matter must be removed
before the water is discharged. Also, alkaline drainage contains
sediment which requires removal.
Many preparation plants in the United States use water to assist
in the sizing, separation, and cleaning of run-of-mine coal. The
waste slurry discharged from the plant is often high in suspended
coal fines that require reduction or removal prior to recycle or
discharge. Also, coal preparation facilities generate a solid or
semisolid refuse of material rejected from the cleaned coal.
Ash, clays, and other materials make up this refuse, which is
conveyed as a slurry to a refuse pile, or disposed of in some
other manner.
The creation of these sludges result from application of the BPT
requirement. Additional sludge generation resulting from the
candidate technologies are discussed in the following paragraphs.
Flocculant Addition and Granular Media Filtration
For mine drainage or preparation plant wastewaters, the applica-
tion of these technologies would result in additional sludge
production of a composition similar to sludge generated by BPT
requirements. However, the amount of this extra solid waste
would be minimal in comparison with quantities produced by
compliance with BPT. For instance, in the acid drainage sub-
category, the average TSS removal (which makes up a substantial
portion of the solid waste) at a typical mine by application of
BPT is 1,310 pounds per day. Installation of flocculant addition
equipment would result in an additional estimated removal of 40
361
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pounds per day, or a little over three percent of the BPT sludge
production. For application of filtration technology, additional
sludge production would be approximately 80 pounds per day, or
less than 6.5 percent of the sludge produced under the BPT
requirement.
Total Recycle Option-Preparation Plants
The BAT option is being considered only for preparation plant
wastewaters (distinct from preparation plant associated area
wastewater). As in the previous case, the additional sludge
resulting from selection of the zero discharge option would be
minimal. Again, using a typical facility, 370,000 pounds per day
are removed from the wastewater by application of settling (BPT)
technology (this figure does not include the small amounts of any
gypsum or other "spectator" solids that might settle). Installa-
tion of facilities to achieve total recycle would remove an
additional 140 pounds per day from waters discharged to the
environment.
Settling - Reclamation Areas
The Agency is proposing requirements for areas under reclamation
and for sites where mining has ceased. Because these require-
ments are based on a technology whose installation is already
required by another federal agency (the Office of Surface
Mining), there will be no incremental non-water quality impacts
resulting from the EPA proposal. Because the composition of the
settled material does not include toxic metals, the environmental
impacts of solid waste disposal in this subcategory are projected
to be minimal.
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SECTION IX
AMENDMENTS TO BPT
Three subcategories were established as the basis for promulga-
tion of effluent limitations based on application of the best
practicable technology currently available. These subcategories
include coal preparation plants and associated areas, alkaline
mine drainage, and acid mine drainage. A fourth subcategory was
also established for reclamation areas. A western mines (those
located west of the 100th meridian) subcategory was also
proposed. The catastrophic precipitation event exemption was
investigated for any necessary modifications. Extension of the
period of applicability for certain effluent limitations for post
mining discharges from deep mines was also considered.
WESTERN MINES
As discussed in Section V, western mines are not subcategorized
separately.
POST MINING DISCHARGES
Reclamation Areas
This subcategory was established during the NSPS rulemaking, but
the Agency deferred publication of any limitations until further
data could be gathered and analyzed. As discussed in Sections V
and VII, additional data have been collected that support the
establishment of this subcategory. Pollutants to be regulated
include settleable solids and pH.
The Agency has concluded that the following limitations shall
apply to the reclamation areas subcategory for mining of coal of
all ranks including, but not limited to, lignite, bituminous, and
anthracite:
Effluent Limitations
Effluent Characteristic
Settleable Solids
PH
Maximum for
Any One Day
0.5 ml/1
within the range
6.0 to 9.0
at all times
30 Day
Average
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Underground Mine Discharges
EPA has evaluated the length of time that effluent limitations
should remain in effect after a mine has closed and reclamation
of the area initiated. This is discussed in Sections V and VII.
In the case of deep mines, the pertinent effluent limitations
will remain effective until the applicable reclamation bond has
been released, ensuring that pollution abatement will continue
until effective sealing and reclamation has been completed.
These limitations are tabulated under the applicable mine
drainage subsection.
CATASTROPHIC PRECIPITATION EVENT EXEMPTION
A further revision to BPT, in reference to sedimentation ponds,
deals with catastrophic precipitation events (CPE). Studies
indicate that even when sedimentation pond size is in compliance
with certain design criteria (i.e., if the pond is designed to
contain the amount of water resulting from a 10-year, 24-hour
storm), during certain rainfall events less than the 10-year,
24-hour event, TSS concentrations remain higher than the
established limitations. This is the case even for optimally
designed and operated ponds. However, as discussed in Section
VII, settleable solids are consistently removed during various
rainfall events.
The Agency will adopt the following exemption provision:
Any overflow, increase in volume of a discharge or discharge from
a bypass system caused by precipitation within any 24-hour period
less than or equal to the 10-year, 24-hour precipitation event
(or snowmelt resulting in equivalent volume) shall be subject to
the following alternate limitations:
Effluent Limitations
Effluent Characteristic
Settleable Solids
PH
Maximum for
Any One Day
0.5 ml/1
within the range
6.0 to 9.0
at all times
30 Day
Average
Any overflow, increase in volume of a discharge or discharge from
a by-pass system caused by precipitation within any 24-hour
period greater than the 10-year, 24-hour precipitation event (or
snowmelt resulting in equivalent volume) shall be subject to the
following alternate limitations:
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Effluent Limitations
Effluent Characteristic
pH
Maximum for
Any One Day
within the range
6.0 to 9.0
at all times
30 Day
Average
These alternate limitations shall be available only if the facil-
ity is designed, constructed, operated, and maintained to contain
at a minimum the volume of water which would drain into the
facility during a 10-year, 24-hour precipitation event (or snow-
melt of equivalent volume). The treatment facility must also be
designed, constructed, operated, and maintained to consistently
achieve the applicable effluent limitations during periods of no
precipitation (or snowmelt) and to ensure that the pH in the
final effluent remains in the range of 6.0 to 9.0 during the
precipitation event (or snowmelt). The operator shall have the
burden of demonstrating to the appropriate authority that the
prerequisites for the alternate limitations have been met.
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SECTION X
BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE (BAT)
The factors considered in assessing best available technology
economically achievable (BAT) include the age of equipment and
facilities involved, the process employed, process changes, non-
water quality environmental impacts (including energy require-
ments) and the costs of application of such technology (Section
304(b)(2)(B)). In general, the BAT technology level represents,
at a minimum, the best economically achievable performance of
plants of various ages, sizes, processes, or other shared charac-
teristics. Where existing performance is uniformly inadequate
BAT may be transferred from a different subcategory or category.
BAT may include process changes or internal controls, even when
not common industry practice.
EPA proposed BAT limitations for two subcategories (coal prepara-
tion plants and preparation plant associated areas) of the coal
mining industry on 13 May 1976 (41 FR 19841). These subcate-
gories were later combined in the modified proposal for BAT
requirements published in the 26 April 1977 Federal Register (42
FR 21380). Also on 13 May 1976, the Agency proposed BAT stand-
ards for the alkaline and acid mine drainage subcategories based
on the application of granular media filtration. These proposed
standards were unchanged in the 26 April publication, pending
toxic pollutant data collection and analysis in keeping with the
Settlement Agreement and the Clean Water Act.
The statutory assessment of BAT "considers" costs, but does not
require a balancing of costs against effluent reduction benefits.
In developing the proposed BAT, however, EPA has given substan-
tial weight to the reasonableness of costs. The Agency has
considered the volume and nature of discharges, the volume and
nature of discharges expected after application of BAT, the
general environmental effects of the pollutants, and the costs
and economic impacts of the required pollution control levels.
Despite this expanded consideration of costs, the primary deter-
minant of BAT remains effluent reduction capability. Effluent
limitations in this industry are expressed as concentrations
(i.e., mass per unit volume, most often milligrams per liter--
mg/1). Mass limitations cannot be written because wastewater
flow cannot be correlated with coal production. This stems from
the fact that, although little process water is employed in coal
extraction, large volumes of water still require treatment
because of infiltration from precipitation and runoff through the
active mining area as well as groundwater seepage from breached
aquifers. Thus a particular mine may have large volumes of water
to treat that are essentially independent of the coal production
capacity of the mine. This situation is also found in the coal
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preparation segment. Although process water used for coal clean-
ing can be correlated with production, wastewater flows are
impossible to predict due to varying amounts of surface runoff
from preparation plant associated areas such as coal stockpiles.
The Agency considered a number of options for regulation of
existing sources subject to the BAT requirement and new sources
subject to the NSPS requirement. The BAT limitations options are
detailed below. New source options are discussed in Section XII.
BAT OPTIONS CONSIDERED
OPTION ONE - Require effluent limitations equivalent to those
promulgated under BPT. For acid drainage mines and coal prepara-
tion plants and associated areas the limitations are based on the
application of neutralization, aeration, and settling technology.
For alkaline mines and areas under reclamation, limitations are
based on application of settling technology.
The basic elements of the storm exemption published on 28
December 1979 (44 FR 76788) are adopted with a number of
modifications.
First, settleable solids and pH limitations will apply during the
exemption period.
Second, the exemption currently requires operators to "contain or
treat" the runoff from a design storm to successfully claim the
exemption. This language has caused unnecessary confusion, since
some have misinterpreted the phrase "to treat." This language
was included to cover those few coal mines where chemical coagu-
lants are added as part of the treatment system. The Agency did
not intend to imply that treatment of storm runoff to a certain
level was required. To eliminate this confusion, EPA has removed
the phrase "to treat" from the exemption language, but includes
as a prerequisite for the exemption a demonstration that the
treatment facility can consistently treat to the "dry weather"
limitations during periods of no precipitation.
Third, discharges from underground mines will no longer be exempt
from effluent limitations, regardless of storm size. Precipita-
tion does not significantly affect the mechanism of underground
mining discharges, and thus no relief from effluent limitations
is necessary. Techniques for minimizing or preventing infiltra-
tion in underground mines are presented later in this section.
The settleable solids and pH limitations that apply during the
exemption period are based on application of settling technology
and were developed from data collected by the Agency during
various types of storm events. Pollutant coverage would be
extended to include post mining discharges from both deep and
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surface mines. These limitations would apply through release of
the applicable reclamation bond.
Additional costs borne by the operator by selection of this
option would be restricted to operation and maintenance costs of
pollution control equipment to comply with the extended pollutant
coverage provisions and for monitoring during the storm exemption
period. These costs are minimal.
OPTION TWO - Require effluent limitations based on flocculant
addition technology. A treatability study commissioned by the
Agency has shown that when toxic metals were spiked into the
untreated wastewater, substantial reduction of these pollutants
was also achieved along with suspended solids. Additional toxic
metal removals for BPT-treated water without spiking were highly
variable due to the low influent levels of these metals.
Costs for installation and operation of this technology would
range from $30,000 to $40,000 per outfall for capital costs and
from $.042/1,000 gallons treated to $.41/1,000 gallons treated
for annual costs.* The cost of implementating this option at
preparation plants and associated areas for the entire U.S. is
50.0 million dollars (capital) and 25.1 million dollars (annual)
for this subcategory.
The extended pollutant coverage and the modified storm exemption
discussed under BAT Option One would also apply here.
OPTION THREE - Require effluent limitations based on the appli-
cation of granular media filtration technology. Two acid drain-
age treatment plants were studied for evaluation of this technol-
ogy. They consisted of BPT treatment (neutralization, aeration,
and settling) of acid mine drainage followed by a dual-media fil-
ter. Toxic metal reductions are not quantified because influent
concentrations of toxic metals to the filter were very low, i.e.,
the neutralization and settling processes effectively removed the
priority metals contained in the raw wastewater.
Capital costs for this technology range from $150,000 for a
design flow of 100,000 gpd to $900,000 for a design flow of
8,000,000 gpd. Annual costs for filtration range from $.51/1,000
gallons treated for the 100,000 gpd facility to $.055/1,000 gal-
lons treated for the 8 mgd facility. No capital and annual costs
were estimated for implementation of this option specifically for
preparation plants and associated areas.
*Note: The lower cost was calculated assuming a two mg/1 dosage
rate and a 4.5 mgd facility; the higher cost was calculated
assuming a two mg/1 dosage rate and a 0.1 mgd facility.
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The extended pollutant coverage and modified storm exemption
discussed in BAT Option One would apply if this option were
selected.
OPTION FOUR - Require no discharge of pollutants from existing
source preparation plants, with one of the other options selected
for the mine drainage subcategories. Associated area drainage
would be segregated from preparation plant wastewaters for
separate treatment. Total recycle would be necessary, with
ditching or diking installed around the slurry pond to divert
storm and other surface runoff. Makeup water would be provided
from an independent source. Associated area drainage would, if
required, be neutralized and settled in a separately constructed
facility. The extended pollutant coverage and storm exemption
discussed in BAT Option One would apply to the associated area
drainage treatment system only.
Total industry capital costs for implementation of this option
are estimated to total 291.2 million dollars. Annual costs are
estimated at 52.6 million dollars.
BAT SELECTION AND DECISION CRITERIA
EPA has selected Option One as the basis for proposed effluent
limitations. Although some small amount of additional metals and
suspended solids removal was provided by Options Two and Three,
the costs associated with installation and operation of these
technologies are too high to warrant such removal. Further,
additional removals at these levels are difficult to accurately
quantify due to the magnitude of analytical error associated with
their measurement.
Options Two and Three provided only small incremental toxic metal
removals and in some cases exhibited virtually no additional
removal at all. Suspended solids removals were quantifiable;
however, these technologies are subject to the BCT "cost reason-
ableness" test. As discussed in Section XI, the Agency has
concluded that the BCT evaluation is not applicable to effluents
from the coal mine industry. Thus, lower BAT limitations based
on these technologies could not be justified.
Option Four for existing preparation plants was not selected,
based upon the high retrofit expenditures. In the Agency's
judgment, the costs of retrofitting for zero discharge are
significantly higher at minimal environmental improvement than
the costs and benefits of the selected option. As noted in
Section XII, New Source Performance Standards (NSPS), this option
was selected for new source preparation plants.
The BAT effluent limitations guidelines for the coal mining
category are summarized in Table X-l.
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Table X-l
EFFLUENT LIMITATIONS BASED ON BEST AVAILABLE
TECHNOLOGY ECONOMICALLY ACHIEVABLE (BAT)
Effluent Limitations
Subcategory and
Effluent
Characteristics
Acid Mine Drainage:
Fe (total)
Mn (total)
TSS
PH
Alkaline Mine Drainage:
Fe (total)
TSS
pH
Preparation Plants and
Associated Areas:
Fe (total)
Mn (total)
TSS
PH
POST MINING DISCHARGES
Areas Under Reclamation
Settleable Solids
PH
Underground Mine
Discharges
Maximum for
any one day
7.0
4.0
70
within the range
6.0 to 9.0
at all times
7.0
70
within the range
6.0 to 9.0
at all times
Average of daily
values for 30
consecutive days
shall not exceed
3.5
2.0
35
7.0
4.0
70
within the range
6.0 to 9.0
at all times
3.5
35
3.5
2.0
35
0.5 ml/1
within the range
6.0 to 9.0
at all times
Effluent limitations that apply
from appropriate active mine
drainage subcategory
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BEST MANAGEMENT PRACTICES (WATER MANAGEMENT)
Section 304(e) of the Clean Water Act (33 U.S.C. 1251) authorizes
the Administrator of EPA to promulgate Best Management Practices
(BMPs) for each class or subcategory of both point and nonpoint
sources of pollution. Under the Surface Mining Control and
Reclamation Act of 1977 (SMCRA) (Public Law 95-87), OSM was
assigned responsibility for the development of a comprehensive
program to ensure environmental protection and land reclamation
of surface coal mining operations. Water handling practices can
include the application of various mining, aquifer and erosion
control techniques to prevent or minimize adverse environmental
effects. The purpose of these techniques is to effect a reduc-
tion in effluent water volumes and/or an improvement in effluent
quality, thereby reducing wastewater treatment and its associated
costs. The following paragraphs discuss water management prac-
tices available to operators and permit authorities to reduce
wastewater quantity.
For both surface mining and the surface effects of underground
mining, OSM has promulgated specific regulations governing water
management associated with mining and reclamation operations (44
FR 15143-15178). A number of these standards have been remanded
as a result of litigation; therefore, OSM is now in the process
of a new rulemaking.
Underground Mines
Surface or groundwater may enter underground mines from above,
below, or laterally through adjacent rock strata. Faults,
joints, and roof fractures are common sites of water entrance
into abandoned underground mines. Water may also enter mines
through exploration drill holes or through boreholes that supply
power and air to underground equipment. Surface water can drain
into underground mines from surface mines or as a result of
inadequate stream diversion practices. Flooding or seepage from
adjacent abandoned or inactive underground mines is often a sig-
nificant source of water infiltration. Factors that can affect
the quantity of water entering a deep mine are: the depth of the
mine, the source of the drainage, the location of water bearing
strata, and groundwater flow patterns. Investigations of the
quantity of water entering underground coal mines have found the
average rate of infiltration to vary between 6,260 and 10,280
liters per hectare per day (670 to 1,100 gal/acre/day). These
rates may be exceeded if catastrophic flooding of a mine occurs
from adjacent or overlying abandoned drifts (1).
Various infiltration control practices are required in order to
comply with OSM regulations restricting the discharge of water
into underground mines (44 FR 15269 sec. 817.55). OSM require-
ments endorsed by EPA include:
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1. Borehole sealing and casing
2. Mine sealing
3. Regrading and revegetation of surface facilities, and
4. Surface water diversion
Borehole Sealing
Underground mines are commonly intercepted by boreholes extending
from the ground surface. These holes are sometimes drilled dur-
ing mineral exploration, but may also be utilized for supplying
power or air to underground equipment or for discharge water
pumped from active sections. Upon abandonment of an underground
mine, these boreholes may collect and transport surface and
groundwater into the mine.
These vertical, or nearly vertical, boreholes can be successfully
sealed from below in an active underground mine. The sealing can
also be achieved by placing packers and injecting a cement grout.
Often abandoned holes will be blocked with debris and will
require cleaning prior to sealing. The packers should be placed
below aquifers overlying the mine to prevent entry of sub-surface
waters, but should be well above the roof to prevent damage to
the seal from roof collapse.
A borehole may also be sealed by filling the hole with rock until
the mine void directly below the hole is filled to the roof.
Successive layers of increasingly smaller stone should be placed
above the rock. A clay and/or concrete plug is then placed in
the borehole. The remainder of the borehole may be filled with
rock or capped.
Mine Sealing
Several techniques contained in the OSM program prevent post-
mining formation of acid mine drainage. One of these techniques
is mine sealing. Mine sealing is defined as the closure of mine
entries, drifts, slopes, shafts, subsidence holes, fractures, and
other openings in underground mines with clay, earth, rock, tim-
ber, concrete, fly ash, grout, and other materials. The purpose
of mine sealing is to control or abate the discharge of mine
drainage from active and abandoned mines.
Mine seals have been classified into three types based on method
of construction and function. The three seal types are:
1. Dry Seal--The dry seal is constructed by placing suit-
able material in mine openings to prevent the entrance of air and
water into the mine. This seal can be applied to openings where
there is little or no water flow from within the mine and little
danger of a hydrostatic head developing.
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2. Air Seal--An air seal prevents the entrance of air into
a mine while allowing the normal mine discharge to flow through
the seal. This seal is constructed with a water trap similar to
the traps in sinks and drains.
3. Hydraulic Seal—Construction of a hydraulic seal
involves placing a plug in a mine opening that is discharging
water. The plug prevents discharge after the mine is flooded.
Flooding excludes air from the mine and retards the oxidation of
sulfide minerals. However, the possibility of the failure of
mine seals or outcrop barriers increases with time as the sealed
mine workings gradually become inundated by groundwater and the
hydraulic head increases. Depending upon the rate of groundwater
influx and size of the mine area, complete inundation of a sealed
mine may take several decades. Consequently, the maximum antici-
pated hydraulic head on the mine seals may not occur for a long
time. In addition, seepage through, or failure of, the coal out-
crop barrier or mine seal could occur at any time.
Surface Area Regrading
Water discharging from underground mines often originates as sur-
face water from ungraded, unvegetated strip mine spoils. This
commonly occurs in the eastern United States where coal outcrops
are often mined by contour stripping techniques. These strip
mines can intercept underground workings or have underground mine
entries and auger holes located along the highwall. When these
openings occur on the updip side of an underground mine, large
volumes of surface water may be conveyed to underground workings.
Surface mines may collect water and allow it to enter a permeable
Coal seam. This water can flow along the seam to adjacent
underground mines.
The purpose of regrading is to return the disturbed area back to
its approximate original contour, with natural drainageways and
watersheds.
Various methods of surface regrading have been practiced in the
eastern coal fields. The selection of a regrading method will
depend upon such factors as: the amount of backfill material
available, the degree of pollution control desired, future land
use, funds available and topography of the area. Prior to
backfilling, impervious materials may be compacted against the
highwall and coal seam to prevent the flow of water to adjacent
underground mines. Where contour terrace regrading methods are
applied, surface runoff is diverted away from the highwall.
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Surface Water Diversion
Surface cracks, subsidence areas, ungraded surface mines, and
shaft, drift and slope openings often are the source of surface
water infiltration into underground mines. Water diversion
entails the interception and conveyance of water around these
underground mine openings. This procedure controls water infil-
tration and decreases the volume of mine water discharge.
Ditches, trench drains, flumes, pipes, and dikes are commonly
used for surface water diversion. Ditches are often used to
divert water around surface mines. Flumes and pipes can be used
to carry water across surface cracks and subsidence areas. To
ensure effective diversion, the conveyance system must be capable
of handling maximum expected flows. Riprap may be required to
reduce water velocities in ditch type conveyance systems.
In addition to the above practices required by OSM, permit
writers may make use of the following water management practices
to assure the control of infiltration into underground mines:
1. Surface or subsurface sealing
2. Channel reconstruction
3. Aquifer interception
4. Subsidence sealing and grading
Surface Sealing
Surface mines that overlie deep mines can collect water in a pit
and this water could percolate into the underground facility. To
Control this, the surface permeability should be reduced which
can be accomplished by placement of impervious materials, such as
concrete, asphalt, rubber, plastic, latex, or clay on the ground
surface. Surface permeability may also be decreased by compac-
tion; however, the degree of success will depend upon soil prop-
erties and the compaction equipment utilized.
A seal below the surface would have several advantages over sur-
face seals: it would be less affected by mechanical and chemical
actions; land use would not be restricted; and the seal would
most likely be located in an area of lower natural permeability.
The seal would be formed by injecting an impermeable material
into the substrata. Asphalt, cement and gel materials have been
used to control water movement below the surface. The effective-
ness of various latexes, water soluble polymers, and water solu-
ble inorganics, which hydrate with existing ground materials to
form cement like substances, has been demonstrated in laboratory
and field tests. However, large scale applications of subsurface
sealants to control acid mine drainage have not been demonstra-
ted.
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Channel Reconstruction
Vertical fracturing and subsidence of strata overlying under-
ground mines often create openings on the ground surface.
Streams flowing across these openings may have a complete or par-
tial loss of flow to the underground workings. During active
operations, pumping of this infiltrating water is required. In
both active and abandoned underground mines the problem of infil-
trating stream flow can be effectively controlled by reconstruct-
ing and/or lining the stream channel. The reconstructed channel
bottom may be lined with an impervious material to prevent seep-
age or flow to the underground mine. To ensure complete and
effective diversion, the reconstructed channel must be capable of
handling peak stream flows.
In instances when stream flow cannot be diverted to a new chan-
nel, flow into underground mines can be controlled by plugging
the mine openings with clay or other impervious material.
Aquifer Interception
This mine water handling technique utilizes hydrogeologic fea-
tures of an underground mine in order to help prevent the inflow
and contamination of groundwater. Wells are drilled from the
land surface through the aquifer to the underground mine. The
groundwater may then be drained through the mine zone for dis-
charge into underlying aquifers, or conveyed from the mine
through a pipe system.
Subsidence Sealing and Grading
Before or after abandonment of underground mines, fracturing or
general subsidence of overlying strata can occur. This fractur-
ing increases the permeability of the strata, and can result in
the flow of large volumes of water into a mine. The volume of
water that is diverted into an underground mine via fracturing or
subsidence depends upon the structure of the overlying rock, and
the surface topography and hydrology of the area.
Vertical permeability may be decreased by placing impermeable
materials around the subsided area. These materials may be com-
pacted on the surface and graded, or placed in a suitable sealing
strata below ground level. Materials which have been success-
fully utilized for subsidence sealing are rubber, clay, concrete,
and cement.
Prevention of Acid Formation
Because sufficient water is almost always present in deep mines
to allow acid formation, methods for reducing oxygen availability
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and contact time are important in preventing this reaction.
Reduction of contact time can be accomplished during active oper-
ations by pumping water from the mine and maintaining the mine
pool at a sufficiently low level. Pumping costs can be quite
high, particularly if the water sources are diffuse; therefore,
it is also good practice to try and reduce the amount of water
flowing into the mine. For inactive or abandoned mines, mine
sealing is a viable alternative. This method can eliminate
oxygen from entering an underground mine.
Surface Mining
Water handling techniques for surface mines include practices
associated with two categories: (1) mining technology, and (2)
reclamation technology. Pre-mine planning to institute these
practices is very important, as is borne out by the permit pro-
cedures required by OSM. The mining and reclamation techniques
discussed in this subsection represent source control methods
that can contain or prevent pollution formation during active
mining.
Mining Methods
Certain mining techniques can help reduce the environmental
impacts of coal strip mining. One such technique currently
employed by industry and favored by OSM is termed "Modified Block
Cut" mining.
This method is basically applicable to moderate slopes (20° or
less), low highwalls (60 feet average) and thin seams. It has
been applied to mines located in the east. This technique is
expected to be feasible in even steeper terrain.
The modified block cut method is a variation of conventional con-
tour strip mining (2). Material from the first cut is often
stored in a valley or head of hollow fill. This initial cut is
usually three times wider than each succeeding cut in order to
accommodate excess spoil as the mining plan progresses. After
completion of each cut, a void is created near the highwall to
store pollutant-forming materials encountered during mining.
Overburden from the next cut is backfilled into the previous cut
simultaneously exposing coal and .initiating reclamation. This
method offers several advantages:
1. Overburden is handled only once,
2. Most of the spoil is confined to a mined area,
3. Spoil on the downslope is almost completely eliminated
thereby reducing the amount of disturbed area,
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4. Reclamation is concurrent, and
5. Grading and revegetation areas are reduced.
Figure X-l illustrates the "Modified Block Cut" method.
Excess Spoil Disposal
According to OSM regulations, spoil not used in returning the
land to approximate original contour must be hauled and placed in
a designated disposal area. The operator must ensure that leach-
ate and surface runoff from the fill will not harm the surface
waters or groundwater and the fill area must be suitable for
reclamation. The regulations allow three types of fill design:
valley, head-of-hollow, and durable rock.
A valley fill can be described as follows: a structure located
in a hollow where the fill material has been hauled and compacted
into place with diversion of upstream drainage around the fill.
In addition, according to OSM regulations, valley fills must meet
rules for subdrainage and filter systems.
Head-of-hollow fills are constructed in a manner similar to val-
ley fills. However, instead of diverting upstream drainage
around the fill, a rock-core chimney, constructed from the toe to
the head of the fill, passes drainage through a fill core. In
addition, head-of-hollow fills must completely fill the disposal
site to the approximate elevations of the ridge line (3). Figure
X-2 illustrates a head-of-hollow fill.
Durable rock fills represent a third type of valley fill but can
be utilized only if the amount of durable rock (i.e., rocks which
do not slake in water) is 80 percent of the total fill volume.
Spoil material is dumped over a berm located at the head of the
fill. The rock material forms a natural blanket drainway across
the bottom of the fill. A drainage system is required but the
regulations leave design open to the operator (3).
Reclamation
Proper reclamation techniques play a vital role in overall
environmental quality control for any mining operation. Recla-
mation is considered an integral part of the overall mining plan.
According to SMCRA, as contemporaneously as practicable with
operations, all disturbed land shall be reclaimed to a condition
equal to or exceeding any previous use which such lands were cap-
able of supporting immediately prior to any exploration or mining
function. Reclamation techniques center basically on regrading
and revegetation.
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Cut I
Highwall-—
Hill
Diagram A
Volley
Spoil Bank
Spoil Backfill
Outcrop Barrier
Cut 2-
Cut I
Highwall-—
Hill
Diagram 8
Valley
Valley
Hill
Diagram D
Cut
Valley
Hill
Diagram E
Cut 5
Valley
Hill
Diagram F
Cut 5
Valley
Source: (1)
Figure X-1
MODIFIED BLOCK CUT
37.9
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Strip Mine Bench
Crowned
Terraces
PLAN
Crowned
Terraces.
Original
Ground Surface
Highwall
Fill
Lateral Drain
Rock Filled
Natural Drainway
Figure X-2
CROSS SECTION OF TYPICAL HEAD-OF-HOLLOW FILL
Source: (1)
380
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Regrading
The purposes of regrading include the following:
(a) Aesthetic improvement of the land surface
(b) Returning the land to usefulness
(c) Providing a suitable base for revegetation
(d) Burial of pollution-forming materials
(e) Reducing erosion
(f) Eliminating landsliding
(g) Encouraging natural drainage
(h) Eliminating ponding
(i) Eliminating hazards, such as high cliffs, deep pits and
deep ponds
(j) Controlling water pollution.
Regrading, as applied to surface mining, is currently defined as
that of reconstructing the approximate original contour.
Regrading is often more difficult in older surface mines where
mining was conducted with less regard to environmental concern.
For example, spoil was often placed without consideration of
future regrading requirements.
Contour strip mines in steep terrain create special problems
where the spoil was deposited over the outslope. The terrain
becomes difficult to cover with topsoil prior to regrading.
Achieving a suitable surface for revegetation on abandoned mines
becomes complicated because spoil segregation was rarely prac-
ticed. Topsoil usually was not segregated or stockpiled and
pollution-producing materials are often well mixed throughout the
spoil. This emphasizes the importance of regrading methods such
as soil spreading and burying of pollution-forming materials.
Revegetation techniques such as soil supplementation and spoil
segregation are also important. Practices such as water diver-
sion and sealing both underground mine openings and auger holes
in highwalls can eliminate many erosional and/or pollution prob-
lems otherwise encountered during regrading and revegetation.
A major characteristic of most open pit mines or quarries is the
large area required for disposal of overburden and processing
wastes. Usually the required disposal acreage exceeds the actual
381
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pit area. Careful management of topsoil and overburden must be
maintained for later use in land reclamation. Proper disposal of
wastes avoids leaching of toxic materials from waste sites.
Revegetation and regrading techniques help avoid water infiltra-
tion and severe erosion losses which could eventually result in
landslides and severe pollutant loadings in nearby waters. Each
of these practices is specified under OSM regulations.
Revegetation
Proper revegetation is one of the most effective pollution and
erosional control methods for surface,mined lands. Revegetation
results in aesthetic improvement, and returns land to agricul-
tural, recreational, or silvicultural usefulness.
A dense ground cover stabilizes the surface with its root system,
reduces velocity of surface runoff, and functions as a filter to
remove sediment from water flowing over and through it. This
vegetative cover will annually contribute organic matter to the
surface and can greatly reduce erosion. Eventually the soil pro-
file develops into a complete soil ecosystem. The soil bacteria
act as an oxygen barrier by consuming oxygen as it enters the
soil from the atmosphere. The amount of pollution formed due to
oxidation of materials lying below the soil horizon is thus
greatly reduced.
A soil profile also tends to act as a sponge by retaining water
near the surface. The retained water acts as a surface coolant
as it evaporates from the surface. The resulting decrease in
surface temperature enhances vegetative growth. Additionally,
water retained at the surface or evaporated from the surface does
not pass through underlying spoil material, thereby averting
potential pollution problems.
Loss of the topsoil is a major hindrance to revegetation and,
therefore, topsoil stockpiling is required by OSM. To protect
the stockpile from erosion, OSM regulations require that quick-
growing annual and perennial plants be seeded on the pile.
Revegetation can be an entire pollution control plan in some
instances, but generally it must be an integral part of more com-
prehensive plans that incorporate water diversion, overburden
segregation, and regrading.
Past revegetation efforts were primarily concerned with planting
trees. However, to establish vegetative cover adequately, tree
planting must be accompanied by establishment of dense ground
covers of grasses and legumes that are compatible with the local
plants and local environment. Again, OSM regulations specify
many facets of revegetation and reclamation.
382
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Erosion and Sediment Control
The most widely practiced method of erosion control is diversion
of water. Diverting streams and surface runoff to avoid con-
tamination from mined or disturbed areas is required by OSM.
Diversion involves collection of water before it enters a mine
area and conveyance of that water around or through the mine site
to a suitable disposal area. Structures used for these purposes
include diversion dikes, diversion ditches or swales, diversion
pipes, and flumes (4, 5). Flumes and pipes are used mainly in
areas of steep terrain or to carry water across regraded areas.
A dike, a ridge of compacted soil, is used to simply divert the
flow of water, whereas a ditch or diversion system collects the
water and transfers it to a suitable disposal area. Erosion can
also be controlled by reducing the velocity of the water. This
can be done by spreading rip rap over the area, by using check
dams, or by using sandbag or straw bale barriers (see Figure
X-3). The establishment of vegetation will also decrease erosion
Diversion techniques are directed toward preventing water from
entering a mined area. Runoff control employs various methods to
handle water after it has reached the mine site. Erosional dam-
age due to runoff can be effectively and inexpensively controlled
by the establishment of vegetation. In areas where vegetation
cannot be established, rip rap can be used to reduce erosion.
Slope reduction and terracing of embankments are also effective
in achieving runoff control.
In general, diversion and runoff control methods alone are insuf-
ficient to prevent erosion and therefore sedimentation. Methods
of sediment control during active mining are needed to remove
sediments from the runoff before it is discharged.
The most common method of sediment control is the use of sedimen-
tation ponds as required by OSM. In some cases, certain tech-
niques may be employed to enhance sedimentation pond performance.
One such method is the use of straw bale dikes (see Figure X-3).
This is a replaceable barrier constructed out of straw bales.
The dike intercepts the runoff, reduces the water's velocity, and
detains small amounts of sediment (4). Another technique is the
use of in-pond baffles to reduce short circuiting and thereby
increase retention time.
Water Infiltration Control
Control of surface infiltration involves either isolating waste
material from the water supply or decreasing the surface perme-
ability. Generally, it is not feasible to isolate the large
amounts of waste material generated by mining operations. Also,
the waste material may be needed as backfill during regrading
383
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A. SANDBAG BARRIERS
B. LOG CHECK DAM
Source: USEPA, Erosion and Sediment Control-Surface Mining
in the Eastern U.S., 1976.
Figure X-3
SEDIMENT TRAPS
38^-
-------
FLOW
10.2 cm
(4") VERTICAL FACE
EMBEDDING DETAIL
ANGLE FIRST STAKE
TOWARD PREVIOUSLY
LAID BAIL
FLOW
WIRE OR NYLON BOUND
BALES PLACE ON THE
CONTOUR
2 RE-BARS, STEEL PICKETS, OR
5.1 cm x 5.1 cm (2" x 2") STAKES
0.46 m to 0.61 m (!%' to 2') IN GROUND
ANCHORING DETAIL
C. STRAW BALE BARRIER
Figure X-3 (Continued)
SEDIMENT TRAPS
385
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operations. Under these conditions, if infiltrating water is
causing formation of pollutants, abatement will require on-site
control of infiltration such as contained disposal of toxic
wastes or decreasing the surface permeability.
Controlling water infiltration from rainfall and subsurface
sources can be accomplished by placing impervous barriers on or
around the waste material, establishing a vegetative cover, or
constructing underdrains. Impervious barriers, constructed of
clay, concrete, asphalt, latex, plastic, or formed by special
processes such as carbonate bonding, can prevent water from
reaching the waste material.
A dense vegetative cover has varying effects on infiltration.
For instance, vegetation tends to reduce the velocity of water,
thereby inducing infiltration. Conversely, a vegetative cover
will build up a soil profile, which tends to increase the surface
retention of water. This water is available for evaporation and
can result in a net decrease in the amount of water entering
underlying materials. Vegetation also utilizes large quantities
of water in its life processes (again decreasing the amount of
water that will reach the underlying material). When infiltra-
tion is caused by interception of surface flow, it is usually
beneficial to divert the flow. One or more of the techniques
illustrated in the erosion and sediment control subsection may be
employed for this purpose.
Underdrains are often used to control water infiltration after it
has entered the waste material. By offering a quick escape
route, contact time between water and any pollutant-forming
material contained in the waste is reduced. Also, water flow
paths through pollution-forming materials are shortened. The
possibility of a fluctuating water table is eliminated. Under-
drain discharges should be monitored to determine the nature of
pollutants contained therein. Underdrains also serve as collec-
tion points to concentrate diffuse groundwater drainage making
any required treatment of this wastewater more manageable.
Infiltration can also occur via exploration drillholes or via
other holes drilled during mining operations although as previ-
ously mentioned, OSM regulations require that these drillholes be
cased, sealed or otherwise managed in a manner that avoids
drainage into groundwater.
386
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SECTION XI
BEST CONVENTIONAL POLLUTANT CONTROL TECHNOLOGY
The 1977 amendments added Section 301(b)(4)(E) to the Act, estab-
lishing "best conventional pollutant control technology" (BCT)
for discharges of conventional pollutants from existing indus-
trial point sources. Conventional pollutants are those defined
in Section 304(b)(4)—BOD, TSS, fecal coliform, and pH--and any
additional pollutants defined by the Administrator as "conven-
tional." On 30 July 1978, EPA designated oil and grease as a
conventional pollutant (44 FR 44501).
BCT is not an additional limitation; rather it replaces BAT for
the control of conventional pollutants. BCT requires that limi-
tations for conventional pollutants be assessed in light of a
"cost-reasonableness" test which involves a comparison of the
cost and level of reduction of conventional pollutants from the
discharge of publicly owned treatment works (POTWs) to the cost
and level of reduction of such pollutants from a class or cate-
gory of industrial sources. As a part of its review of BAT for
certain "secondary" industries, the Agency has promulgated a
methodology for this cost test (44 FR 50732, 29 August 1979).
The Agency compares costs with that of an "average POTW with a
flow of 2 mgd and costs (1979 dollars) of $1.51 per pound of
pollutant removal (TSS).
The BCT test is of questionable utility for this industry. Flow
volumes at coal mines are extremely variable, with 90 percent of
the mines falling within a range of 0.006 mgd to 5 mgd. The
median flow is 0.25 mgd, while the mean flow is 1 mgd. The mean
flow falls at the 75th percentile, indicating a very unequal
distribution. This variability makes it difficult to compare the
level and thus the cost of reduction of pollutants in coal mining
wastewaters with the cost and level of reducing the same
pollutants in POTWs.
In compliance with statutory factors, the Agency completed the
BCT cost test for Level Two (flocculant addition) and Level 4
(granular media filtration) as a function of mine drainage flow
rate. The results are presented in Figure XI-1 and Table XI-1.
Higher flow rates significantly reduce the cost per pound of
treatment.
As explained in Section X, the Agency has not selected either
Level 2 or Level 4 as BAT technology, but will retain BPT as the
best available technology. Also, the technologies considered for
conventional pollutant removal are identical to those considered
for toxic pollutant removal. These two factors establish, by
definition, that the best conventional pollutant control
technology for this industry meets the BCT cost test.
387
-------
o
LJLJ
O
IS
LJ
IT
CO
co
CO
O
o
DESIGN FLOW IN M.G.D.
Level 2 - Flocculant Addition
Level 4 - Granular Media Filtration
Figure XI-1
BCT COST CURVES
388
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Table XI-1
COAL MINING, POINT SOURCE CATEGORY
COST PER POUND OF TSS REMOVED
BCT TEST
Flow
-------
SECTION XII
NEW SOURCE PERFORMANCE STANDARDS (NSPS)
The basis for new source performance standards (NSPS) under
Section 306 of the Act is through application of the best avail-
able demonstrated technology. New mining facilities have the
opportunity to implement the best and most efficient coal mining
processes and wastewater technologies. Congress, therefore,
directed EPA to consider the best demonstrated process changes
and end-of-pipe treatment technologies capable of reducing
pollution to the maximum extent feasible.
New source performance standards were proposed on 13 May 1976 (41
FR 19841) and 19 September 1977 (42 FR 46932) and promulgated on
12 January 1979 (44 FR 2586). The Agency has reviewed these
standards and established a number of options.
NSPS OPTIONS CONSIDERED
The Agency considered the following four NSPS options:
Option One. Require achievement of performance standards in each
subcategory based on the same technology proposed for BAT,
including neutralization and settling for acidic wastewaters.
This option is predicated on application of the same technology
proposed for BPT for the acid drainage and preparation plant and
associated areas subcategories. The alkaline drainage and areas
under reclamation subcategories would be required to meet perfor-
mance standards based on settling technology. No additional
expenditures would be required from selection of this option.
Option Two. Require achievement of performance standards based
on flocculant addition. As discussed in Section X, this tech-
nology would provide some additional reduction of solids, but
would not provide a cost-effective decrease in toxic pollutant
levels, which were found to be extremely low.
Option Three. Require achievement of performance standards based
on granular media filtration. As in the case of Option Two,
granular media filtration would provide some additional reduction
of solids, but would not provide a cost-effective decrease in
toxic pollutant levels.
Option Four. Require achievement of no discharge of process
wastewater pollutants in the coal preparation plant subcategory
with one of the other options selected for the mine drainage
subcategories. Economic and environmental considerations have
already provided the incentive to design processes in existing
preparation plants which partially or completely reuse process
water. The zero discharge requirement would prohibit the
391
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discharge of any pollution-bearing streams from the preparation
plant water circuit, including the treatment system. No storm
exemption would be available.
NSPS SELECTION AND DECISION CRITERIA
EPA has selected Options One and Four as the basis for proposed
new source performance standards. The rationale for selecting
Option One was discussed in Section X. In Option Four, the
preparation plant subcategory is separated from the associated
areas subcategory for new sources. Many existing facilities are
practicing total recycle of preparation plant wastewaters, thus
zero discharge is a demonstrated technology for these facilities.
Further, this option becomes feasible for new sources because
treatment system and water management planning can be implemented
from the design phase, eliminating the economic and technical
inefficiency associated with retrofitting.
The new source performance standards corresponding to Options One
and Four may be found in Section X.
392
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SECTION XIII
PRETREATMENT STANDARDS
Section 307(b) of the Act requires EPA to promulgate pretreatment
standards for both existing sources (PSES) and new sources (PSNS)
of pollution which discharge their wastes into publicly owned
treatment works (POTWs). These pretreatment standards are
designed to prevent the discharge of pollutants which pass
through, interfere with, or are otherwise incompatible with the
operation of POTWs. In addition, the Clean Water Act of 1977
adds a new dimension to these standards by requiring pretreatment
of pollutants, such as heavy metals, that limit POTW sludge man-
agement alternatives. The legislative history of the Act indi-
cates that pretreatment standards are to be technology based and,
with respect to toxic pollutants, analogous to BAT. The Agency
has promulgated general pretreatment regulations which establish
a framework for the implementation of these statutory require-
ments (see 43 FR 27736, 16 June 1978).
EPA is not proposing pretreatment standards for existing sources
(PSES) in the coal mining point source category at this time nor
does it intend to promulgate such standards in the future (PSNS)
since there are no known or anticipated dischargers to publicly
owned treatment works (POTWs). Coal mines are located in rural
areas, often far from population centers and publicly owned
treatment plants. No rational mine operator would choose to
route the high volume mine discharge to a POTW for treatment.
This is true for existing sources and will continue to be true
for new sources, and thus pretreatment standards would be
irrelevant and unnecessary.
393
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SECTION XIV
ACKNOWLEDGEMENTS
This document was prepared by Radian Corporation, McLean,
Virginia with direction from Mr. Dennis Ruddy of the Energy and
Mining Branch of the Effluent Guidelines Division of EPA.
Direction and assistance were also provided by Mr. William A.
Telliard, Chief of the Energy and Mining Branch and Technical
Project Officer for this study, and Mr. Matthew Jarrett and Mr.
Ron Kirby, Effluent Guidelines Technical Project Monitors.
Much of the input for this document was provided by Radian's sub-
contractors Frontier Technical Associates, Buffalo, New York and
Hydrotechnic Corporation, New York, New York. An earlier version
of this document was developed and written by Versar
Incorporated, Springfield, Virginia. Much of the information
developed by Versar was incorporated in this draft.
The following agencies and divisions of agencies contributed to
the development of this document:
Environmental Protection Agency
1. All regional offices
2. Industrial Environmental Research Laboratory
Cincinnati, Ohio
3. Office of Research and Development
4. Office of General Counsel
5. Office of Analysis and Evaluation
6. Monitoring and Data Support
7. Criteria and Standards Division
Pennsylvania Department of Environmental Resources
Bituminous Coal Research
National Coal Association
Many coal companies were very cooperative in providing access to
coal mines and coal preparation plants for various sampling and
engineering studies. Of particular assistance were:
395
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AMAX Coal Company
Beltrami Enterprises, Incorporated
Beth-Elkhorn Corporation
Bethlehem Mines Corporation
Bill's Coal Company
Buffalo Mining Company
Central Ohio Coal Company
Clemens Coal Company
Consolidation Coal Company
Drummond Coal Company
Duquesne Light Company
Eastern Associates Coal Company
Falcon Coal Company
Harmar Coal Company
Industrial Generating Company
Inland Steel Coal Company
Island Creek Coal Company
Jewell Ridge Coal Company
Jones Se Laughlin Steel Corporation
Kaiser Steel
Kentland Coal Corporation
King Knob Coal Company
Knife River Coal Company
Monterey Coal Company
National Mines Corporation
North American Coal Company
Old Ben Coal Company
Peabody Coal Company
Peter Kiewit & Sons, Incorporated
Pittston Coal Company
Southwestern Illinois Coal Company
U.S. Steel
V. St J. Carlson
Washington Irrigation & Development Company
Western Energy Company
396
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SECTION XV
REFERENCES
Section III
1. Nielsen, George F., ed., 1979 Keystone Coal Industry Manual,
McGraw Hill, New York, New York, 1979.
2. Nielsen, George F., ed., 1980 Keystone Coal Industry Manual,
McGraw Hill, New York, New York, 1980.
3. The President's Commission on Coal, Coal Data Book, U.S.
Government Printing Office, Washington, D.C., February 1980.
4. "U.S. Coal Unlikely to Meet Carter's Production Goal," Oil
and Gas Journal, Volume 77, No. 46, pages 205-210,
November 12, 1979.
5. U.S. Department of the Interior, Bureau of Mines, "Coal -
Bituminous and Lignite in 1975," Washington, D.C., 1976.
6. Wilmoth, R. C., et al., "Removal of Trace Elements from Acid
Mine Drainage," EPA-Industrial Environmental Research
Laboratory and Hydroscience, Inc., for U.S. EPA, Contract
No. 68-03-2568, EPA 600/7-79-101, April 1979.
397
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Section IV
1. Cassidy, Samuel M., ed., Elements of Practical Coal Mining,
American Institute of Mining, Metallurgical, and Petroleum
Engineers, Inc., New York, New York, 1973.
2. Berkowitz, N., An Introduction to Coal Technology, Academic
Press, New York, 1979.
3. Wachter, R. A. and T. R. Blackwood, "Source Assessment:
Water Pollutants from Coal Storage Areas," IERL, EPA,
Cincinnati, May 1978.
4. Jackson, Dan, "Western Coal is the Big Challenge to
Reclamation Experts Today," Coal Age, Volume 82, No. 7,
pages 90-108, July 1977.
5. "Technical Assistance in the Implementation of the BAT
Review of the Coal Mining Industry Point Source Category,"
U.S. Environmental Protection Agency, prepared by Versar,
Inc., Contract Nos. 68-01-3273, 4762, 5149, and 68-02-2618,
Draft, July 1979.
6. Leonard, J. W. and D. P. Mitchell, editors, Coal
Preparation, Seeley W. Mudd Series, The American Institute
of Mining, Metallurgical, and Petroleum Engineers, Inc., New
York, 1968.
7. Argonne National Laboratory, "Environmental Control
Implications of Generating Electric Power from Coal,"
Technology Status Report, Appendix A, Part 1, "Preparation
and Cleaning Assessment Study," Argonne, Illinois, 1977.
8. Energy Information Administration: Annual Report to
Congress, Vols. II & III, 1977.
9. U.S. Department of the Interior, Bureau of Mines, Minerals
Yearbook. Volume I: Metals, Minerals and Fuels, 1976
edition, Washington, D.C.
10. Pennsylvania Department of Environmental Resources, "Annual
Report on Mining, Oil and Gas, and Land Reclamation and
Conservation Activities," Harrisburg, Pennsylvania, 1977 and
1978 Reports.
11. Terlecky, P. Michael, and David M. Harty, "Inventory of
Anthracite Coal Mining Operations, Wastewater Treatment and
Discharge Practices," by Frontier Technical Associates,
Inc., for U.S. Environmental Protection Agency, Contract No.
68-01-5163, October 1979.
398
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12. Jackson, Dan, "Outlook Shines for Coal Slurry Lines," Coal
Age, Volume 83, No. 6, pages 88-93, June 1978.
13. Nielsen, George F., ed., 1979 Keystone Coal Industry Manual,
McGraw Hill, New York, New York, 1979.
14. "U.S. Coal Unlikely to Meet Carter's Production Goal," Oil
and Gas Journal, Volume 77, No. 46, pages 205-210, November
12, 1979.
15. Bureau of Mines: Minerals Yearbooks, 1968-1976.
Congressional Research Service:National Energy
Transportation, Volume Ill-Issues and Problems7 March 1978.
16. Buckley, B., et al., "Effects of a Flexible Definition of
New Source Performance Standards for Utility Boilers Firing
Anthracite Coal," by Environmental Research and Technology,
Inc., for U.S. Department of Energy, September 1978.
17. Averitt, P., "Coal Resources of the United States - January
1, 1974," Geological Survey Bulletin 1412, U.S. GPO,
Washington, D.C., 1975.
18. Department of the Interior: Energy Perspectives 2, June
1976.
19. U.S. Department of the Interior, Bureau of Mines, "Coal -
Bituminous and Lignite in 1975," Washington, D.C., 1976.
2.0. Nielson, George F., ed., 1976 Keystone Coal Industry Manual,
McGraw-Hill, Inc., New York, 1976.
21. "Water Pollution Impact of Controlling Sulfur Dioxide
Emissions from Coal-Fired Steam Electric Generators," Radian
Corporation, EPA Contract No. 68-02-2608, U.S. EPA-IERL,
Research Triangle Park, North Carolina, 1977.
399
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Section V
1. Wilmoth, R. C., "Limestone and Lime Neutralization of Acid
Mine Drainage," U.S. EPA, IERL, Cincinnati, Ohio,
EPA-600/2-77-101, May 1977.
2. Wilmoth, R. C., "Limestone and Limestone-Lime Neutralization
of Acid Mine Drainage," U.S. EPA, Office of Research and
Development, Cincinnati, Ohio, EPA-670/2-74-051, June 1974.
3. Wilmoth, R. C., "Application of Reverse Osmosis to Acid Mine
Drainage Treatment," U.S. EPA, Office of Research and
Development Cincinnati, Ohio, EPA-670/2-73-100, December
1973.
4. "Testing of Neutralization and Precipitation of Coal Mine
Acid Mine Drainage," Hydrotechnic Corporation, EPA Contract
No. 68-01-5163, U.S. EPA, Washington, D.C., September 1979,
draft report.
5. "Testing of Dual Granular Media Filtration of Treated Acid
Mine Drainage," Hydrotechnic Corporation, EPA Contract No.
68-01-5163, U.S. EPA, Washington, D.C., March 1980,
preliminary draft.
6. "Treatability of Coal Mine Drainage for Removal of Priority
Pollutants," Radian Corporation, McLean, Virginia, EPA
Contract No. 68-01-5163, U.S. EPA, Washington, D.C., January
1980, preliminary draft.
7. Wilmoth, R. C., "Removal of Trace Elements from Acid Mine
Drainage," U.S. EPA, lERL-Cincinnati and Hydroscience, Inc.,
EPA Contract No. 68-03-2568, EPA 600/7-79-101, April 1979.
8. U.S. EPA, "Sampling and Analysis Procedures for Screening of
Industrial Effluents for Priority Pollutants," Environmental
Monitoring and Support Laboratory, Cincinnati, Ohio, March
1977, revised April 1977.
9. "Inductively-Coupled Plasma-Atomic Emission Spectrometric
Method for Trace Element Analysis of Water and Wastes," U.S.
EPA-EMSL, Cincinnati, Ohio, June 1979.
10. "Mine Drainage Treatment and Costing Study: Coal Mining
Industry," U.S. Environmental Protection Agency, prepared by
Hydrotechnic Corporation, Contract Nos. 68-02-2608 and
68-01-5163, December 1979.
400
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11. Martin, J. F., "Quality of Effluent from Coal Refuse
Piles," U.S. EPA, Cincinnati, Ohio, 1974.
12. Yancey, H. F., M. R. Greer, et al., "Properties of Coal and
Impurities in Relation to Preparation," pages 1.3 to 1.53 in
Leonard and Mitchell, eds., Coal Preparation, American
Institute of Mining, Metallurgical, and Petroleum Engineers,
Inc., New York, 1968.
13. "Development Document for Effluent Limitations Guidelines
and New Source Performance Standards for the Steam Electric
Power Generating Point Source Category," U.S. EPA
4401/1-74-029-a, October 1974.
14. U.S. Bureau of Land Management, Northwest Colorado Coal,
final environmental statement, 4 Volumes, undated.
15. U.S. Geological Survey, Development of Coal Resources in
Central Utah, draft environmental statement, Part 1-Regional
analysis; Part 2-Site specific analysis, 1978.
16. U.S. Department of the Interior, Office of Surface Mining
Reclamation and Enforcement, Permanent Regulatory Program
Implementing Section 501(b) of the Surface Mining Control
and Reclamation Act of 1977, draft environmental statement,
September 1978.
17. U.S. Bureau of Land Management, Northwest Colorado Coal
Regional Environmental Statement"] supplemental report,
undated.
18. Wachter, R. A. and T. R. Blackwood, "Source Assessment:
Water Pollutants from Coal Storage Areas," IERL, EPA,
Cincinnati, Ohio, May 1978.
19. Anderson, W. C. and M. C. Youngstrom, "Coal Pile Leachate-
Quality and Quality Characteristics," ASCE, Journal of the
Environmental Engineering Division, Volume 102, No. EE6,
pages 1239 to 1253, 1976.
20. Terlecky, P. Michael and D. M. Harty, "Inventory of
Anthracite Coal Mining Operations, Wastewater Treatment
and Discharge Practices,", by Frontier Technical Associates,
Inc. for U.S. Environmental Protection Agency, Contract No.
68-01-5163, Final Report, June 10, 1980.
401
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Section VI
1. "Sampling and Analysis Procedures for Screening of Industrial
Effluents for Priority Pollutants,." U.S. Environmental
Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio, March 1977, Revised April 1977.
2. "Condensed Chemical Dictionary," P. Hawley, Van Norstrand,
Reinhold, New York, New York, 1971.
3. "Development Document for BAT Effluent Limitations Guidelines
and New Source Performance Standards for the Ore Mining and
Dressing Industry," Calspan Report No. 6332-M-1, September 5,
1979.
4. Rawlings, G. D., and M. Samfield, Environmental Science and
Technology, Vol. 13, No. 2, February 1974.
5. "Seminar for Analytical Methods for Priority Pollutants,"
U.S. Environmental Protection Agency, Office of Water
Programs, Savannah, Georgia, May 23-24, 1978.
402
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Section VII
1. Lovell, Harold L., "An Appraisal of Neutralization Processes
to Treat Coal Mine Drainage," Pennsylvania State University,
University Park, Pennsylvania, November 1973.
2. Wilmoth, Roger C., et al., "Removal of Trace Elements from
Acid Mine Drainage," EPA Industrial Environmental Research
Laboratory and Hydroscience, Inc., for U.S. Environmental
Protection Agency Contract No. 68-03-2568, EPA 660/7-79-101,
April 1979.
3. "Environmental Control Selection Methodology for a Coal
Conversion Demonstration Facility," U.S. Department of
Energy, prepared by Radian Corporation, Contract No.
EX-760-C-01-2314, October 1978.
4. "Treatability of Coal Mine Drainage for Removal of Priority
Pollutants: Effluent Limitations Guidelines for the Coal
Mining Point Source Category," U.S. Environmental Protection
Agency, prepared by Versar, Inc., Contract No. 68-01-4762,
Draft, September 1979.
5. "Process Design Manual for Suspended Solids Removal," U.S.
Environmental Protection Agency Technology Transfer, EPA
625/1-75-0039, January 1975.
6. "Erosion and Sediment Control: Surface Mining in the
Eastern U.S.," U.S. Environmental Protection Agency, EPA
625/3-76-006, October 1976.
7. Ettinger, Charles E. and J. E. Lichty, Evaluation of
Performance Capability of Surface Mine Sediment Basins,
Harrisburg,Pennsylvania,Skelly and Loy, August 1979.
8. Environmental Protection Agency, Resource Extraction &
Handling Division, Sedimentation Ponds - A Critical Review,
report, Cincinnati, Ohio,undated.
9. Hill, Ronald D., Water Pollution from Coal Mines, EPA,
August 1973.
10. Hill, Ronald D., "Sediment Control and Surface Mining,"
Presented at the Polish-U.S. Symposium Environmental
Protection in Openpit Coal Mining, Denver, Colorado, May
1975.
403
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11. Grim, Elmore G. and Ronald D. Hill, Environmental Protection
in Surface Mining of Coal, final report, Cincinnati, Ohio,
U.S. EPA, National Environmental Research Center, Office of
Research and Development, October 1974.
12. Kathuria, D. Vir, M. A. Nawrocki and B. C. Becker,
Effectiveness of Surface Mine Sedimentation Ponds, Columbia,
Maryland, Hittman Associates,Inc., August 1976.
13. Environmental Protection Agency, Development Document for
Interim Final Effluent Limitations Guidelines and New Source
Performance Standards for the Coal Mining Point Source
Category, Washington, D.C., May 1976.
14. Lanouette, Kenneth H., "Heavy Metals Removal," Chemical
Engineering, Vol. 84, No. 22, pp. 73-80, October 1977.
15. "Mine Drainage Treatment and Costing Study: Coal Mining
Industry," U.S. Environmental Protection Agency, prepared by
Hydrotechnic Corporation, Contract Nos. 68-02-2608 and
68-01-5163, November 1979.
16. "Development Document for BAT Effluent Limitations
Guidelines and New Source Performance Standards for the Ore
Mining and Dressing Industry," U.S. Environmental Protection
Agency, prepared by Calspan Corporation, Contract No.
68-01-4845, Draft, September 1979.
17. "Processes, Procedures, and Methods to Control Pollution
from Mining Activities," U.S. Environmental Protection
Agency, prepared by Skelly and Loy and Penn Environmental
Consultants, Inc., Contract No. 68-01-1830, EPA
430/9-73-011, October 1973.
18. "Technical Assistance in the Implementation of the BAT
Review of the Coal Mining Industry Point Source Category,"
U.S. Environmental Protection Agency, prepared by Versar,
Inc., Contract Nos. 68-01-3273, 4762, 5149, 68-02-2618,
Draft, July 1979.
19. Wilmoth, Roger C., Applications of Reverse Osmosis to Acid
Mine Drainage Treatment, 2 copies, EPA, Crown Mine Drainage
Control Field Site, December 1973.
20. "Handbook of Chemistry and Physics," 50th edition, Weast, R.
C., editor, Chemical Rubber Company, Cleveland, Ohio, p.
B252.
21. "Handbook of Analytical Chemistry," Meites, L., editor,
McGraw-Hill, New York, pp. 1-15 to 1-19, 1963.
404
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22. "Ionic Equilibrium as Applied to Qualitative Analyses,"
Hogness and Johnson, Holt Rinehart & Winston Company, New
York, pp. 360-362, 1954.
23. "Testing of the Neutralization and Precipitation of Coal
Mine Acid Mine Drainage," U.S. Environmental Protection
Agency, prepared by Hydrotechnic Corporation, Contract No.
68-01-5163, final report, November 1979.
24. "Testing of Dual Granular Media Filtration of Treated Acid
Coal Mine Drainage," U.S. Environmental Protection Agency,
prepared by Hydrotechnic Corporation, Contract No.
68-01-5163, final report, August 1980.
25. "Testing of Dual Granular Media Filtration of Treated Acid
Coal Mine Drainage at a Second Site," U.S. Environmental
Protection Agency, prepared by Hydrotechnic Corporation,
Contract No. 68-01-5163, final report, December 1980.
26. Janiak, Henryk, "Purification of Waters Discharged from
Polish Lignite Mines," Central Research and Design Institute
for Open-pit Mining, Wroclaw, Poland, for U.S. Environmental
Protection Agency, EPA 600/7-79-099, April 1979.
27. Mann, Charles E., "Optimizing Sediment Control Systems," in
Surface Coal Mining and Reclamation Symposium; Coal
Conference Sc Expo V, October 23-25, Louisville, Kentucky,
McGraw-Hill, Inc., New York, 1979.
28. Huck, P. M., K.. L. Murphy, C. Reed, (McMaster Univ.
Hamilton, Ontario, Canada) and B. P. LeClair, (Environmental
Protection Service, Ottawa, Ontario, Canada) "Optimization
of Polymer Flocculation of Heavy Metal Hydroxides," Journal
WPCF, pp. 2411-2418, December 1977.
29. Reese, R. D. and R. E. Neff, (American Cyanimid Company)
"Flocculation-Filtration Studies on Acid Coal Mine
Drainage," BCR-MD70-86, June 15-19, 1970.
30. Brodeur, T. and D. A. Bauer, "Picking the Best Coagulant for
the Job," Water and Wastes Engineering, Vol. 11, No. 5, p.
52-57, 1974":
405
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Section VIII
1. "Mine Drainage Treatment and Costing Study: Coal Mining
Industry," U.S. Environmental Protection Agency, prepared by
Hydrotechnic Corporation, Contract Nos. 68-02-2608 and
68-01-5613, December 1979.
2. "Coal Mine Industry Mine Drainage Treatment and Costing
Study: Backup Data," U.S. Environmental Protection Agency,
prepared by Hydrotechnic Corporation, March 20, 1980.
3. Ruddy, Dennis, U.S. Environmental Protection Agency,
communication to Leo Ehrenreich and Harold Kohlmann, outline
of preparation plant scenarios, March 18, 1980.
4. Curtis, Robert, "Mine Drainage Treatment Costing File: A Set
of Notes and Phone Call Memos on the Cost of Treating Mine
Drainage," Radian Corporation, McLean, Virginia, January
1980.
5. Randolph, K. B., Versar, Inc., memorandum to Dennis. Ruddy,
U.S. Environmental Protection Agency, regarding cost
multipliers for coal mining regions of the United States,
January 25, 1979.
6. "Environmental Control Selection Methodology for a Coal
Conversion Demonstration Facility," U.S. Department of
Energy, prepared by Radian Corporation, October 1978.
7. Gumerman, R. C., et al., "Estimating Water Treatment Costs:
Volume 2. Cost Curves Applicable to 1 to 200 MGD Treatment
Plants," U.S. Environmental Protection Agency, prepared by
Culp/Wesner/Culp Consulting Engineers, Contract No.
68-03-2516, EPA-600/2-79-162b, August 1979.
406
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Section X
1. "Processes, Procedures, and Methods to Control Pollution
from Mining Activities," U.S. Environmental Protection
Agency, prepared by Skelly and Loy and Penn Environmental
Consultants, Inc., Contract No. 68-01-1830, EPA
430/9-73-011, October 1973.
2. Grim, Elmore C. and R. D. Hill, Environmental Protection in
the Surface Mining of Coal, Final Report, Cincinnati, Ohio;
USEPA, National Environmental Research Center, Office of
Research and Development, October 1974.
3. Joyce, Christopher R., Final Federal Surface Mining
Regulations, Washington, D.C., McGraw-Hill, 1980.
4. "Erosion and Sediment Control: Surface Mining in the
Eastern U.S.," U.S. Environmental Protection Agency, EPA
625/3-76-006, October 1976.
5. "Technical Assistance in the Implementation of the BAT
Review of the Coal Mining Industry Point Source Category,"
U.S. Environmental Protection Agency, prepared by Versar,
Inc., Contract Nos. 68-01-3273, 4762, 5149, 68-02-2618,
Draft, July 1979.
407
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SECTION XVI
GLOSSARY
absorption: The process by which a liquid is drawn into and
tends to fill permeable pores in a porous solid body; also
the increase in weight of a porous solid body resulting from
the penetration of liquid into its permeable pores.
acid: A substance which dissolves in water with the formation of
hydronium ion. A substance containing hydrogen which may be
displaced by metals to form salts.
acid mine drainage (AMD): Synonomous with "ferruginous mine
drainage." That drainage which before any treatment has a
pH of less than 6.0 or a total iron concentration of more
than 10.0 mg/1.
acidity: The quantitative capacity of aqueous solutions to react
with hydroxyl ions (OH"). The condition of a water
solution having a pH of less than 7.
acre-foot: A term used in measuring the volume of water that is
equal to the quantity of water required to cover 1 acre 1
foot deep, or 43,560 ft3.
Act: The Federal Water Pollution Control Act, as amended (33
U.S.C. 1251, 1311 and 1314(b) and (c), P.L. 92-500). Also
called the Clean Water Act and amendments through 1977.
activated carbon: Carbon which is treated by high-temperature
heating with steam or carbon dioxide producing an internal
porous particle structure. Activated carbon is often used
to adsorb organic pollutants and/or remove metal ions.
active mining area: An area where work or other activity
relating to the extraction, removal or recovery of any coal
is being conducted. This includes areas where secondary
recovery of coal is being conducted, but specifically does
not include for surface mines any area of land on or in
which grading to return the land to the desired contour has
been completed and reclamation work has begun.
Administrator: Administrator of the U.S. Environmental
Protection Agency, whose duties are to administer the Act;
adsorption: The adhesion of an extremely thin layer of molecules
(of gas, liquid) to the surfaces of solids (granular
activated carbons for instance) or liquids with which they
are in contact.
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alkaline mine drainage: That mine drainage which before any
treatment has a pH of more than 6.0 and a total iron
concentration of less than 10.0 mg/1.
advanced waste treatment: Any treatment method or process
employed following biological treatment (1) to increase the
removal of pollution load, (2) to remove substances which
may be deleterious to receiving waters or the environment,
(3) to produce a high-quality effluent suitable for reuse in
any specific manner or for discharge under critical
conditions. The term tertiary treatment is commonly used to
denote advanced waste treatment methods.
aerated pond: A natural or artificial wastewater treatment pond
in which mechanical.or diffused air aeration is used to
supplement the oxygen supply.
aeration: The bringing about of intimate contact between air and
liquid by one of the following methods: spraying the liquid
in the air, bubbling air through the liquid (diffused
aeration), agitation of the liquid to promote surface
absorption of air (mechanical aeration).
agglomeration: The coalesence of dispersed suspended matter into
larger floes or particles which settle more rapidly.
alkalinity: The capacity of water to neutralize acids, a
property imparted by the water's content of carbonates,
bicarbonates, hydroxides, and occasionally borates,
silicates, and phosphates. It is expressed in milligrams
per liter of equivalent calcium carbonate.
anion: The charged particle in a solution of an electrolyte
which carries a negative charge.
anion exchange process: The reversible exchange of negative ions
between functional groups of the ion exchange medium and the
solution in which the solid is immersed. Used as a
wastewater treatment process for removal of anions, e.g.,
carbonate.
anthracite: A hard natural coal of high luster which contains
little volatile matter, and greater than 927* fixed carbon.
anticline: A fold that is convex upward. The oldest strata are
closest to the axial plane of the fold.
aquifer: A subsurface rock formation that is capable of
producing water.
410
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areas under reclamation: A previously surface mined area where
regrading has been completed and revegetation has
commenced.
asbestos minerals: Certain minerals which have a fibrous
structure, are heat resistant, chemically inert and
possessing high electrical insulating qualities. The two
main groups are serpentine and amphiboles. Chrysotile
(fibrous serpentine, 3MgO . 2SiC>2 • 2H20) is the
principal commercial variety. Other commercial varieties
are armosite, crocidolite, actinolite, anthophyllite, and
tremolite.
auger: Any drilling device in which the cuttings are
mechanically and continuously removed from the borehole
without the use of fluids; usually used for shallow drilling
or sampling.
auger mining: Spiral boring for additional recovery of a coal
seam exposed in a highwall.
backfilling: The transfer of previously moved material back into
an excavation such as a mine or ditch, or against a
constructed object.
backwashing: The process of cleaning a rapid sand or mechanical
filter by reversing the flow of water.
base: A compound which dissolves in water to yield hydroxyl ions
(OH-).
bench: The surface of an excavated area at some point between
the material being mined and the original surface of the
ground on which equipment can be set, move or operate. A
working road or base below a highwall as in contour
stripping for coal.
best available technology economically achievable (BATEA or BAT):
The level of technology applicable to effluent limitations
to be achieved by July 1, 1984, for industrial discharges to
surface waters as defined by Section 301(b) (2) (A) of the
Act.
best practicable control technology currently available (BPCTCA
or BPT): Treatment required by July 1, 1977 for industrial
discharge to surface waters as defined by Section 301 (b) (1)
(A) of the Act.
best available demonstrated technology (BADT): Treatment rquired
for new sources as defined by Section 306 of the Act.
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biochemical oxygen demand (BOD): A measure of water
contamination expressed as the amount of dissolved oxygen
(mg/1) required by microorganisms, during stabilization of
organic matter by aerobic chemical action.
bituminous: A coal of intermediate hardness containing between
50 and 92 percent fixed carbon.
blowdown: A portion of water in a closed system which is removed
or discharged in order to prevent a buildup of dissolved
solids.
carbon absorption: A process utilizing the efficient absorption
characteristics of activated carbon to remove both dissolved
and suspended substances.
cation: The positively charged particles in solution of an
electrolyte.
cationic flocculant: In flocculation, surface active substances
which have the active constituent in the positive ion. Used
to flocculate and neutralize the negative charge residing on
colloidal particles.
chemical analysis: The use of a standard chemical analytical
procedure to determine the concentration of a specific
pollutant in a wastewater sample.
chemical coagulation: The destabilization and initial
aggregation of colloidal and finely divided suspended matter
by the addition of a floe-forming chemical.
chemical oxygen demand (COD): A specific test to measure the
amount of oxygen required for the complete oxidation of all
organic and inorganic matter in a water sample which is
susceptible to oxidation by a strong chemical oxidant.
chemical precipitation: (1) Precipitation induced by addition
of chemicals. This includes the reaction of dissolved
substances such that they pass out of solution into the
solids phase. (2) The process of softening water by the
addition of lime and soda ash as the precipitants.
chrysotile: A mineral of the serpentine group, Mg3$i205
(OH)4.
clarification: A physical-chemical wastewater treatment process
involving the various steps necessary to form a stable,
rapid settling floe and to separate it by sedimentation.
Clarification may involve pH adjustment, precipitation,
coagulation, flocculation, and sedimentation.
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clarifier: A basin usually made of steel in which water flows at
a low velocity to allow settling of suspended matter.
coagulation: The treatment process by which a chemical added to
wastewater acts to neutralize the repulsive forces that hold
waste particles in suspension.
coagulants: Materials that induce coagulation and are used to
precipitate solids or semi-solids. They are usually
compounds which dissociate into strongly charged ions.
coal mine: An area of land with all property placed upon, under
or above the surface of such land, used in or resulting from
the work of extracting coal from its natural deposits by any
means or method including secondary recovery of coal from
refuse or other storage piles derived from mining, cleaning,
or preparation of coal.
coal mine drainage: Any water drained, pumped or siphoned from a
coal mine.
coal pile drainage: Drainage from a coal pile as a result of
percolation or runoff from rainfall.
colloids: Suspensions of particles, usually between a nanometer
and a micrometer in diameter, in any physical state. In
this size range the surface area is so great compared to the
volume that unusual phenomenon occur, i.e., particles do not
settle out by gravity and are small enough to pass through
normal filter membranes (i.e., not ultrafilters).
composite wastewater sample: A combination of individual samples
of water or wastewater taken at selected intervals,
generally hourly for some specified period, to minimize the
effect of the variability of the individual sample.
Individual samples may have equal volume or may be roughly
proportioned to the flow at time of sampling.
concentration, hydrogen ion: The weight of hydrogen ions in
grams per liter of solution. Commonly expressed as the pH
value that represents the logarithm of the reciprocal of the
hydrogen ion concentration.
conventional pollutants: pH, BOD, fecal coliform, oil and
grease, and TSS.
crusher, jaw: A primary crusher designed to reduce the size of
materials by impact or crushing between a fixed plate and an
oscillating plate or between two oscillating plates, forming
a tapered jaw.
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crusher, roll: A reduction crusher consisting of a heavy frame
on which two rolls are mounted; the rolls are-driven so that
they rotate toward one another. Coal is fed in from above
and nipped between the moving rolls, crushed, and discharged
below.
cyclone: (a) The conical-shaped apparatus used in dust
collecting operations and fine grinding applications; (b) A
classifying (or concentrating) separator into which pulp is
fed, so as to take a circular path. Coarser and heavier
fractions of solids report as the apex of long cone while
finer particles overflow from central vortex.
data correlation: The process of the conversion of reduced data
into a functional relationship and the development of the
significance of both the data and the relationship for the
purpose of process evaluation.
decant structure: Apparatus for removing clarified water from
the surface layers of tailings or settling ponds.
deep mine: An underground mine.
dense-media separation: (a) Heavy media separation, or sink
float. Separation of heavy sinking from light floating
mineral particles in a fluid of intermediate density; (b)
Separation of relatively light (floats) and heavy
particles (sinks), by immersion in a bath of intermediate
density.
denver cell: A flotation cell of the subaeration type, in wide
use. Design modifications include receded disk,
conical-disk, and multibladed impellers, low-pressure air
attachments, and special froth withdrawal arrangements.
denver jig: Pulsion-suction diaphragm jig for fine material, in
which makeup (hydraulic) water is admitted through a rotary
valve adjustable as to portion of jigging cycle over which
controlled addition is made.
dependent variable: A variable whose value is a function of one
or more independent variables.
deposit: Mineral, coal or ore deposit is used to designate a
natural occurrence of a useful mineral, coal, or an ore, in
sufficient extent and degree of concentration to permit
exploitation.
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depressing agent; depressor; depressant: In the froth flotation
process, a substance which reacts with the particle surface
to render it less prone to stay in the froth, thus causing
it to wet down as a tailing product (contrary to activator) .
detention time: The time allowed for solids to collect in a
settling tank. Theoretically , detention time is equal to
the volume of the tank divided by the flow rate. The actual
detention time is determined by operating parameters of the
tank.
dewater: To remove a portion of the water from a sludge or a
slurry.
differential flotation: Separating a raw coal into ttfo or more
coals and pyrites by flotation; also called selective
flotation. This type of flotation is made possible by the
use of suitable depressors and activators.
discharge: Outflow from a pump, drill hole, piping system,
channel, weir or other discernible, confined or discrete
conveyance (see also point source).
discharge pipe: A section of pipe or conduit from the condenser
discharge to the point of discharge into receiving waters or
cooling device.
dispersing agent: Reagent added to flotation circuits to prevent
flocculation, especially of objectionable colloidal slimes.
Sodium silicate is frequently added for this purpose.
dissolved solids: Theoretically, the anhydrous residues of the
dissolved constituents in water. Actually, the term is
defined by the method used in determination. In water and
wastewater treatment, the Standard Methods tests are used.
disturbed area: An area which has had its natural condition
altered in the process of mining coal, preparing coal, or
other mine related activities. This includes but is not
limited to all areas affected by grubbing and topsoil
removal; road construction; construction of mine facilities;
coal mining, reclamation and preparation activities;
deposition of topsoil, overburden, coal or waste materials,
etc. These areas are classified as "disturbed" until said
areas have been returned to approximate original contour (or
post-mining land use) and topsoil (where appropriate) has
been replaced.
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dragline: A piece of excavating equipment which employs a
cable-hung bucket to remove overburden.
drift: A deep mine entry driven directly into a horizontal or
near horizontal mineral seam or vein when it outcrops or is
exposed at the ground surface.
effluent: Liquid, such as wastewater, treated or untreated
which flows out of a unit operation, reservoir or treatment
plant. The influent is the incoming stream.
eluate: Solutions resulting from regeneration (elution) of ion
exchange resins.
eluent: A solution used.to extract collected ions from an ion
exchange resin or solvent and return the resin to its active
state.
embankment (or impoundment): Storage basin made to contain
wastes from mines or preparation plants.
erosion: Processes whereby solids are removed from their
original location on the land surface by hydraulic or wind
action.
filter, granular: A device for removing suspended solids from
water, consisting of granular material placed in a layer(s)
and capable of being cleaned by reversing the direction of
the flow.
filter, rapid sand: A filter for the purification of water which
has been previously treated, usually by coagulation and
sedimentation. The water passes downward through a
filtering medium consisting of a layer of sand,
prepared anthracite coal or other suitable material, usually
from 24 to 30 inches thick and resting on a supporting bed
of gravel or other porous medium. The filtrate is removed
by an underdrain system. The filter is cleaned periodically
by reversing the flow of the water upward through the
filtering medium; sometimes supplemented by mechanical or
air agitation during backwashing to remove mud and other
impurities that are lodged in the sand.
filter, vacuum: A filter consisting of a cylindrical drum
mounted on a horizontal axis, covered with a filter cloth
revolving with a partial submergence in liquid. A vacuum is
maintained under the cloth for the larger part of a
revolution to extract moisture and the cake is scraped off
continuously.
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filtration: The process of passing a liquid through a filtering
medium for the removal of suspended or colloidal matter.
final contour: The surface shape or contour of a surface mine
(or section thereof) after all mining and earth moving
(regrading) operations have been completed.
floe: A very fine, fluffy mass formed by the aggregation of fine
suspended particles.
flocculants: Any substance which will cause flocculation. They
are specifically useful in wastewater treatment. Lime,
alum, and ferric chloride are examples of inorganic
flocculants and polyelectrolytes are organic flocculants.
flocculate: To cause to aggregate or to coalesce into small
lumps or loose clusters, e.g., the calcium ion tends to
flocculate clays.
flocculation: In water and wastewater treatment, the
agglomeration of colloidal and finely divided suspended
matter after coagulation by gently stirring by either
mechanical or hydraulic means.
flotation: The method of coal or mineral separation in which a
froth created in water by a variety of reagents floats some
finely crushed coal or minerals, whereas pyrites and other
minerals sink.
flotation agent: A substance or chemical which alters the
surface tension of water or which makes it froth easily.
The reagents used in the flotation process include pH
regulators, slime dispersants, resurfacing agents, wetting
agents, conditioning agents, collectors, and frothers.
flume: An open channel or conduit on a prepared grade.
froth, foam: In the flotation process, a collection of bubbles
resulting from agitation, the bubbles being the agenct for
raising (floating) the particles of coal or ore to the
surface of the cell.
frother(s): Substances used in flotation processes to make air
bubbles sufficiently permanent principally by reducing
surface tension. Common frothers are pine oil, creyslic
acid, and amyl alcohol.
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flow model: A mathematical model of the effluent wastewater
flow, developed through the use of multiple linear
regression techniques.
flow rate: Usually expressed as liters/minute (gallons/minute)
or liters/day (million gallons/day). Design flow rate is
that used to size the wastewater treatment process. Peak
flow rate is 1.5 to 2.5 times design and relates to the
hydraulic flow limit and is specified for each plant. Flow
rates can be mixed as batch and continuous where these two
treatment modes are used in the same plant.
frequency distribution: An arrangement or distribution of
quantities pertaining to a single element in order of their
magnitude.
grab sample: A single sample of wastewater taken at neither a
set time nor flow.
gravity separation: Treatment of coal or mineral particles which
exploits differences between their specific gravities.
Their sizes and shapes also play a minor part in separation.
Performed by means of jigs, classifiers, hydrocyclones,
dense media, shaking tables, Humphreys spirals, sluices,
vanners and briddles.
grinding: (a) Size reduction into relatively fine particles.
(b) Arbitrarily divided into dry grinding performed on coal
or mineral containing only moisture as mined, and wet
grinding, usually done in rod, ball or pebble mills with
added water.
groundwater table (or level): Upper surface of the underground
zone of saturation.
grout: A fluid mixture of cement, sand (or other additives) and
water that can be poured or pumped easily.
hardness: A characteristic of water, imparted by salts of
calcium, magnesium, and iron, such as bicarbonates,
carbonates, sulfates, chlorides, and nitrates, that causes
curdling of soap, deposition of scale in boilers, damage in
some industrial process, and sometimes objectionable taste.
It may be determined by a standard laboratory procedure or
computed from the amounts of calcium and magnesium as well
as iron, aluminum, manganese, barium, strontium, and zinc,
and is expressed as equivalent calcium carbonate.
heavy-media separation: See dense-media separation.
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highwall: The unexcavated face of exposed overburden and coal in
a surface mine or the face or bank on Che uphill side of a
contour strip mine excavation.
hydrocyclone: A cyclone separator in which a spray of water is
used.
hydroclassifier: A machine which uses an upward current of water
to remove fine particles from coarser material.
hydrology: The science that relates to the water systems of the
earth.
independent variable: A variable whose value is not dependent on
the value of any other variable.
influent: The liquid, such as untreated or partially treated
wastewater, which flows into a reservoir, process unit, or
treatment plant. The effluent is the outgoing stream.
in-plant control: Those treatment techniques that are used to
reduce, reuse, recycle, or treat wastewater prior to end-of
pipe treatment.
ion: A charged atom, molecule or radical, the migration of which
affects the transport of electricity through an electrolyte.
ion exchange: A chemical process involving reversible
interchange of ions between a liquid and solid but no
radical change in the structure of the solid.
jig: A machine in which the feed is stratified in water by means
of a pulsating motion and from which the stratified products
are separately removed, the pulsating motion being usually
obtained by alternate upward and downward currents of the
water.
jigging: A process used to separate coarse materials in the coal
or ore by means of differences in specific gravity in a
water medium.
lagoon: Man-made ponds or lakes usually 4 feet deep (or up to 18
feet if aerated) which are used for storage, treatment, or
disposal of wastes. They can be used to hold wastewater for
removal of suspended solids, to store sludge, cool water, or
for stabilization of organic matter by biological oxidation.
Lagoons can also be used as holding ponds, after chemical
clarification and to polish the effluent.
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lignite: A carbonaceous fuel ranked between peat and bituminous
coal.
lime: Any of a family of chemicals consisting essentially of
calcium hydroxide made from limestone (calcite) which is
composed almost wholly of calcium carbonate or a mixture of
calcium and magnesium carbonates.
lime slurry: A form of calcium hydroxide in aqueous suspension
that contains free water.
linear regression: A method to fit a line through a set of
points such that the sum of squared vertical deviations of
the point values from the fitted line is a minimum, i.e., no
other line, no matter how it is computed, will have a
smaller sum of squared distances between the actual and
predicted values of the dependent variable.
magnetic separator: A device used to separate magnetic from less
magnetic or nonmagnetic materials.
mathematical model: A quantitative equation or system of
equations formulated in such a way as to reasonably depict
the structure of a situation and the relationships among the
relevant variables.
mean value: The statistical expected or average figure.
median value: A data observation located at the 50th percentile
or the midrange.
mesh size (activated carbon): The particle size of granular
activated carbon as determined by the U.S. Sieve series.
Particle size distribution within a mesh series is given in
the specification of the particular carbon.
milligrams per liter (mg/1): This is a mass per volume
designation used in water and wastewater analysis.
minable: (a) Capable of being mined. (b) Material that can be
mined under present day mining technology and economics.
mine: (a) An opening or excavation in the earth for the purpose
of excavating minerals, coals, metal ores or other
substances by digging. (b) A word for the excavation of
minerals by means of pits, shafts, levels, tunnels, etc., as
opposed to a quarry, where the whole excavation is open. In
general the existence of a mine is determined by the mode in
which the mineral is obtained, and not by its chemical or
geologic character. (c) An excavation beneath the surface
of the ground from which mineral matter of value is
extracted.
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mine drainage: Mine drainage usually implies gravity flow
of wastewater from coal mining to a point away from the
mining operation. However, this term encompasses any
wastewater emanating from a coal mining or preparation
operation.
mixed-media filtration: A filter which uses two or more filter
materials of differing specific gravities selected so as to
produce a filter uniformly graded coarse to fine.
mulching: The addition of materials (usually organic) to the
land surface to curtail erosion or retain soil moisture.
multiple linear regression: A method to fit a plant through a
set of points such that the sum of squared distances between
the individual observations and the estimated plane is a
minimum. This statistical technique is an extension of
linear regression in that more than one independent variable
is used in the least squares equation.
neutralization: Adjustment of pH by the addition of acid or
alkali until a pH of about 7.0 is achieved. See pH
adjustment.
new source: Any point source, the construction of which is begun
after the publication of proposed Section 306 regulations.
new source performance standard (NSPS): Performance standards
for the industry and applicable new sources as defined by
Section 306 of the Act.
NPDES permits: National Pollutant Discharge Elimination System
Permits are issued by the EPA or an approved state program
in order to regulate point-source discharge to public
waters.
nonconventional pollutants: Chemical or thermal pollutants,
principally defined by not being a conventional or toxic
pollutant.
normalized coefficients: Regression constants whose magnitudes
are referenced to some value.
open-pit mining, open cut mining: A form of operation designed
to extract coal or minerals that lie near the surface.
Waste, or overburden, is first removed, and the coal or
mineral is broken and loaded.
osmosis: The process of diffusion of a solvent through a
semipermeable membrane from a solution of lower to one of
higher solute concentration.
421
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osmotic pressure: The equilibrium pressure differential across a
semipermeable membrane which separates a solution of lower
from one of higher concentration.
outcrop: The exposing of bedrock or strata projecting through
the overlying cover of detritus and soil.
outfall: The point or location where sewage or drainage
discharges from a sewer, drain or conduit.
overburden: Material of any nature, consolidated or
unconsolidated, that overlies a deposit of useful materials
(i.e., coal, ores, etc.).
overflow: Excess water discharged from the treatment system.
oxidation: The addition of oxygen to a chemical compound, or
any reaction which involves the loss of electrons from an
atom.
oxidized zone: In coal mining, that portion of a refuse pile
near the surface, which has been leached by percolating
water carrying oxygen, carbon dioxide or other gases.
permeability: Capacity for transmitting a fluid.
pH: A measure of the acidity or alkalinity of an aqueous
solution, generally expressed in terms of the hydrogen ion
(H+) or hydronium ion (1130+) content. A pH of below 7 is
considered an acidic solution; and above 7 it is considered
an alkaline solution.
pH adjustment: Treatment of wastewater by the addition of an
acid or alkali to effect a change in the pH or hydrogen ion
concentration. Alkalis such as lime (CaO), limestone
(CaCOs), caustic soda (NaOH), or soda ash (Na2COO,
which supply hydroxyl ions are used to adjust acidic streams
while an acid, usually sulfuric (1*2804) or hydrochloric
(HC1) reacts, with alkaline streams by supplying hydrogen
ions.
pH modifiers: Proper functioning of a cationic or anionic
flotation reagent is dependent on the close control of pH.
Modifying agents used are soda ash, sodium hydroxide, sodium
silicate, sodium phosphates, lime, sulfuric acid, and
hydrofluoric acid.
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pH value: A scale for expressing the acidity or alkalinity of a
solution. Mathematically, it is the logarithm of the
reciprocal of the gram ionic hydrogen equivalents per liter.
Neutral water has a pH of 7.0 and hydrogen ion concentration
of 10~7 moles per liter.
physical-chemical treatment: In this study, it is taken to mean
a method of treating wastewater by the addition of chemicals
to physically separate the pollutant from a stream, usually
by precipitation, followed by settling or flotation of the
wastes. To accomplish this, several processes may be
utilized such as pH adjustment, reduction of hexavalent
chromium, heavy-metal precipitation, coagulation,
flocculation, and clarificaiton by settling.
point source: Any discernible, confined and discrete conveyance,
including but not limited to any pipe, ditch, channel,
tunnel, conduit, well, discrete fissure, container, rolling
stock, concentrated animal feeding operation, or vessel or
other floating craft, from which pollutants are or may be
discharged.
preparation plant: A facility that cleans, sizes and upgrades
run-of-mine coal thereby creating a final coal product prior
to shipping or consumption, and facilities (i.e., slurry
pond, fresh water pond, conveyances) directly associated
with the recycling or discharge of waters used during the
"preparation of coal.
preparation plant ancillary or associated areas: Areas that are
interrelated with coal preparation or coal load out
activities but do not include the preparation plant building
and the preparation plant water recycle/discharge system.
Said areas include but are not limited to ancillary
buildings associated with coal preparation; disturbed areas
in proximity to the preparation plant or related preparation
activities; coal stockpiles; coal refuse storage areas; coal
haulroads and refuse haulroads in proximity to the
preparation plant or coal refuse storage site; treatment
systems designed to handle runoff or seepage from
preparation plant "disturbed" areas, or coal refuse piles
etc.
priority pollutants: Those pollutants included in Table 1 of
Committee Print Numbered 95-30 of the "Committee on Public
Works and Transportation of the House of Representatives,"
subject to the Clean Water Act of 1977, and included in
Table VI-1 of this document.
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pyrites: Mineral group composed of iron and sulfur found in coal
as FeS2«
rank of coal: A classification of coal based upon the fixed
carbon on a dry weight basis and the heat value.
raw mine drainage: Untreated or unprocessed water drained,
pumped or siphoned from a mine.
reagent: A chemical or solution used to produce a desired
chemical reaction; a substance used in flotation.
reclamation: The procedures by which a disturbed area can be
reworked to make it productive, useful, or aesthetically
pleasing, consisting primarily of regrading and
revegetation.
reduction: A chemical reaction which involves the addition of
electrons to a species.
refuse pile: Waste material from a preparation plant. The
material includes pyrites, ash, and water or chemicals used
in cleaning the coal.
regression model: A mathematical model, usually a single
equation, developed through the use of a least squares
linear regression analysis.
reserve: That part of an identified resource from which a usable
mineral and energy commodity can be economically and legally
extracted at the time of determination.
residuals: The differences between the expected and actual
values in a regression analysis.
reverse osmosis: The process of diffusion of a solvent through a
semipermeable membrane from a solution of higher to one of
lower solute concentration, effected by raising the pressure
of the more concentrated 'solution to above the osmotic
pressure.
riprap: Rough stone of various sizes placed compactly or
irregularly to prevent erosion.
room and pillar mining: A system of mining in which the
distinguishing feature is the mining of 50 percent or more
of the coal in the first working. The coal is mined in
rooms separated by narrow ribs (pillars); the coal in the
pillars can be extracted by subsequent working in which the
roof is caved in successive blocks.
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runoff: That part of precipitation that flows over the land
surface from the area upon which it falls.
sampler: A device used with or without flow measurement to
obtain any adequate portion of Water or waste for analytical
purposes. May be designed for taking a single sample
(grab).composite sample, continuous sample, or periodic
sample.
sampling stations: Locations where several flow samples are
tapped for analysis.
scarification: The process of breaking up the topsoil prior to
mining.
sediment: Solid material settled from suspension in a liquid
medium.
sedimentation: The gravity separation of settleable, suspended
solids in a settling basin or lagoon.
settleable solids: (1) That matter in wastewater which will not
stay in suspension during a preselected settling period,
such as 1 hour but either settles to the bottom or floats to
the top. (2) In the Imhoff cone test, the volume of matter
that settles to the bottom of a 1-liter cone in 1 hour.
Settlement Agreement of June 7, 1976: Agreement between the U.S.
Environmental Protection Agency (EPA) and various
environmental groups, as instituted by the United States
District Court for the District of Columbia, directing the
EPA to study and promulgate regulations for a list of
chemical substances, referred to as Appendix A Pollutants.
settling pond: A pond, natural or artificial, for recovering
solids from an effluent.
significance: A statistical measure of the validity, confidence,
and reliability of a figure.
sludge: Accumulated solids separated from a liquid during
processing.
sluice: To cause water to flow at high velocities for wastage,
for purposes of excavation, ejecting debris, etc.
slurry: Solid material conveyed in a liquid medium.
spoil material: Overburden that is removed from above the coal
seam; usually deposited in previously mined areas.
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statistical variance: The sum of the squared deviations about
the mean value in proportion to the likelihood of
occurrence. A measure used to identify the dispersion of a
set of data.
subsidence: Surface depression created by caving of the roof
material in an underground mine.
sump: Any excavation in a mine for the collection of water for
pumping.
suspended solids: (1) Solids which either float on the surface
of or are in suspension in water, wastewater, or other
liquids, and which are removable by a .45 micron filter.
(2) The quantity of material removed from wastewater in a
laboratory test, as prescribed in "Standard Methods for the
Examination of Water and Wastewater" and referred to as
nonfilterable residue, measured in mass per unit volume
(e.g., mg/1).
surface active agent: One which modified physical, electrical,
or chemical characteristics of the surface of solids and
also surface tensions of solids or liquid. Used in froth
flotation (see also depressing agent, flotation agent).
syncline: A fold that is concave upward. The younger strata are
closest to the axial plane of the fold.
table, air: a vibrating, porous table using air currents to
effect gravity concentration of sands or other waste
material from coal.
terracing: The act of creating horizontal or near horizontal
benches.
thickener: A vessel or apparatus for reducing the amount of
water (or conversely, increasing the concentration of
settled material)in a wastewater stream.
tolerance limits: Numerical values identifying the acceptable
range of some variable.
turbidity: Is a measure of the amount of light passing through a
volume of water, which is directly related to the suspended
solids content.
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weir: An obstruction placed across a stream for the purpose of
diverting the water so as to make it flow through a desired
channel, which may be an opening or notch in the weir
itself.
yellowboy: Salt of iron and sulfate formed by treating acid mine
drainage (AMD) with lime; FeS04.
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ABBREVIATIONS
AS
Al
As
BADT
BATEA (BAT)
BCPCT (BCT)
Be
BFR
BMP
BOD
BPCTGA (BPT)
Ca
Cd
CN
COD
CPE
Cr
Cu
CWA
DM
EPA
Fe
FWPCA
Hg
Mg
Mn
Na
Ni
NPDES
NSPS
OSM
Pb
PH
POTW
Silver
Aluminum
Arsenic
Best Available Demonstrated
Technology
Best Available Technology
Economically Achievable
Best Conventional Pollutant
Control Technology
Beryllium
Big Flushing Rain
Best Management Practices
Biochemical Oxidation Demand
Best Practicable Control
Technology Currently Available
Calcium
Cadmium
Cyanide
Chemical Oxygen Demand
Catastrophic Precipitation
Event
Chromium
Copper
Clean Water Act of 1977
Dissolved Metals
Environmental Protection
Agency
Iron
Federal Water Pollution
Control Act of 1972
Mercury
Magnesium
Manganese
Sodium
Nickel
National Pollution Discharge
Elimination System
New Source Performance
Standards
Office of Surface Mining
(Reclamation and Enforcement)
Lead
-Iog10 [H+]
Publicly Owned Treatment Works
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ABBREVIATIONS (Continued)
PSES
PSNS
RCRA
Sb
Se
SMCRA
SS
TDS
Tl
TM
TS
TSS
Zn
Units
FTU
JTU
kkg
mgd
mg/1
mty
ppb
ppm
t
NTU
ug/1
Pretreatment Standards for
Existing Sources
Pretreatment Standards for New
Sources
Resource Conservation and
Recovery Act of 1976
Antimony
Selenium
Surface Mining Control and
Reclamation Act of 1977
Settleable Solids
Total Dissolved Solids
Thallium
Total Metals
Total Solids
Total Suspended Solids
Zinc
Franklin Turbidity Unit
Jackson Turbidity Unit
thousand kilograms
million gallons per day
milligram(s) per liter
million tons per year
part(s) per billion
part(s) per million
ton
Nephelometric Turbidity Unit
microgram(s) per liter
*U.S GOVERNMENT PRINTING OFFICE: 1981-341-085:4632
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