PRELIMINARY DRAFT
A STUDY OF THE COST IMPACT OF THE
RESOURCE CONSERVATION AND
RECOVERY ACT (RCRA) ON THE
DISPOSAL OF NONHAZARDOUS WASTES
FROM MINING
PEDCo ENVIRONMENTAL

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PRELIMINARY DRAFT
'A*'''StUDY~W"TllTTOSTTM^f^F-fHE
RESOURCE CONSERVATION AND
RECOVERY ACT (RCRA) ON THE
DISPOSAL OF NONHAZARDOUS WASTES
FROM MINING
Prepared by
PEDCo Environmental, Inc.
11499 Chester Road
Cincinnati, Ohio 45246
Contract No. 68-03-2577
Work Directive No. 9
PN 3350-1
Prepared for
EPA Technical Project Monitor
S. Jackson Hubbard
Resource Extraction and Handling Division
IERL-Cincinnati
Office of Research and Development
In cooperation with
Land Disposal and Hazardous
Waste Management Divisions
Office of Solid Waste
Washington, D.C.
March 1979

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A. A STUDY OF THE COST IMPACT OF THE RESOURCE CONSERVATION AND RECOVERY ACT
ON THE DISPOSAL OF NONHAZARDOUS WASTES FROM MINING
The main objective of this study is to present estimated total capital
and annual operating costs of mining solid waste disposal technologies that
will satisfy the criteria prescribed in Section 4004 of the Resource
Conservation and Recovery Act (RCRA). The study focuses on the following 10
mining industries: copper, iron ore, molybdenum, gold, lead, zinc, phosphate,
clay, stone, and sand and gravel. These 10 industries contribute about 91
percent of all the nonhazardous mining solid wastes (excluding coal mining
wastes), as shown in Table 1. This table also shows what portion of the
wastes from an industry is considered nonhazardous. All mine wastes (overburden
and waste rock) from these industries are considered nonhazardous, with the
exception of about 30 percent of the phosphate overburden generated in
Florida, which is considered hazardous. Only three of the industries-
clay, sand and gravel, and gold (placer mines only) generate nonhazardous
tailings (beneficiation wastes). Nonhazardous waste from all other domestic
mining industries are shown in various tables in this study as from "other
industries."
The costs are divided, for each criterion, into national baseline
costs; national state- and other Federal-induced costs; and national RCRA
(Criteria-induced) costs (Table 2). The baseline costs represent estimated
costs of control methods already in use by the industry--tailings ponds,
diversion ditches, closure practices—that satisfy or partially satisfy any
of the six RCRA criteria. State-induced costs represent estimated costs of
complying with state standards for the control of nonhazardous wastes; other
Federal-induced costs represent those complying with Federal regulations other
than RCRA. The Clean Water Act of 1977 covers surface waters and wetlands
when an NPDES permit is denied; therefore, the costs of these controls are
considered separate from the Criteria-induced costs. This report does not,
2

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TABLE 1
ESTIMATED MINING INDUSTRY PRODUCTION AND
NONHAZARDOUS WASTE QUANTITIES
(1,000 metric tons)
Mining	No. of		Nonhazardous wastes
industry
mines
Product
Tailings
Mine wastes
Total
Copper
61
244,700

627,900
627,900
Iron ore
68
216,900

234,800
234,800
Molybdenum
3
55

10,740
10,740
Gold
99
0.021
108
8,408
8,516
Lead/zinc
33/36
16,840

4,778
4,778
Phosphate
47
169,300

150,200S
150,200
Clay
1,249
39,770
2,275
33,760
36,035
Stone
5, 584
815,400
Negligible
66,160
66,160
Sand and
gravel
7,007
718,000
35,900
Negligible
35,900
Coal
6,459
573,300

11
H
Other

829,000
21,840+
97,73O0
119,570
Total


60,123
1,234,476
1,294,599
'Represents tailings from gold placer mining. Other gold
mining tailings are considered hazardous.
+Fifty percent of tailings from other mining industries are
considered to be nonhazardous.
^Thirty percent of all phosphate mine waste in Florida is
considered hazardous and thus is not included in this number.
SMCRA is responsible for coal mine wastes.
a
All mine wastes from other mining industries are con-
sidered to be nonhazardous.
3

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TABLE 2
ESTIMATED NATIONAL BASELINE AND REGULATORY COSTS FOR NONHAZARDOUS MINING WASTE CONTROLS
(1,000 dollars)
Wetlands
Costs
Ground water
Surface water
NPDES	NPDES
permit permit
granted denied
Total
Floodplains	Closure
NPDES
permit
granted
NPDES
permit
denied
National baseline
Total capital
Annual OtM
Total annualized
National state- and ,
other Federal-induced
Total capital
Annual OiH
Total annualized
National criteria-
induced
Total capital
Annual OfcM
Total annualized
2,166
111
411
295,900
32,400
96,000
61,500
6,800
19,900
440,800
22,410
98,530
110,500
5,500
34,800
30,300
1,000
• 3,700
26,900
2,700
8,900
250,100
292,000
336,500
54,500
34,500
49,500
208,300
10,400
66,400
206,400
10,300
66,500
1,837,300
159,300
505,700
497,466
57,021
148,441
645,000
49,300
200,900
2,132,100
179,100
601,000
864,800
340,300
533,700
2,105,200
176,400
592,100
*These costs do not include nonhazardous waste control costs for the coal mining industry.

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however, include the costs of control methods for nonhazardous wastes from
coal mining; these wastes are regulated by the Surface Mining Control and
Reclamation Act of 1977 (SMCRA). Estimates of these costs are presented in
the regulatory analysis report prepared to support the final SMCRA regulations
(Federal Register, March 13, 1979). Criteria-induced costs, finally, are
those costs of complying with RCRA that exceed the compliance costs for state
and other Federal standards.
The three cost categories are total capital, annual operation and
maintenance, and total annualized costs. The last is the sum of annualized
capital and annual operation and maintenance costs.
Baseline costs for ground water are minimal when compared with the costs
induced by state and Federal regulations. Baseline costs for surface water,
however, are considerably greater because of the protection afforded by
existing tailings ponds at mine sites. There are no baseline costs for
floodplains and air quality because there are practically no controls
specifically in use to satisfy these criteria. Some industries have measures
that satisfy the RCRA closure criterion. The industries would have to incur
an estimated additional capital cost of $1.84 billion to meet the RCRA closure
criterion.
National baseline capital costs of nonhazardous waste control for all
mining industries are estimated at $497 million. The annualized baseline
control costs are an estimated $148 million. National state- and other
Federal-induced capital costs are estimated at $645 million if NPDES permits
are granted for facilities located in wetlands, and $865 million if these
permits are not granted. Respective annualized costs are $201 million and
$534 million. The total RCRA or Criteria-induced costs are estimated at $2.13
billion (NPDES permits granted) and $2.11 billion (NPDES permits denied).
Respective annualized costs are $601 million and $592 million.
5

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1. Development of Model Plants
Costs attributable to RCRA and other state and Federal legislation were
determined by using the concept of a model plant, because a detailed,
site-by-site study was beyond the scope of this report. For each of the 10
major mineral industries, a model plant was developed that represented the
production level and the quantities of tailings and mine wastes generated.
Production levels were obtained from the Minerals Yearbook, and solid waste
tonnages were obtained from available sources and contacts within the mining
. . . . 1,2
industries.
Figures 1 through 9 display the model plant sizes used in the study.
The model plants include various steps within the process that generate
significant quantities of solid wastes. They also reflect the control
methods that are practiced to some extent within the industry. Each state
was allocated a number of model plants based on the production levels for
that industry within the state.
The model plant size for the copper industry (Figure 1) was determined
on the basis of the total solid wastes generated within the industry, and
from the fact that 25 out of 61 mines produce 93 percent of the Nation's
copper.The model plant, therefore, is a typical mine within the group
of 25 major producing mines.
The iron ore model plant size (Figure 2) was determined by the same
3
method, but with only 54 mines producing all of the Nation's iron ore.
All of the primary molybdenum ore is produced at three mines, and three
model plant sizes were thus developed from information on actual tonnages
obtained from the respective mining companies. The tonnages represent a
molybdenum mine that uses both surface and underground mining methods
(Figure 3).
6

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CHEMICAL
FLOTATION
ADDITIVES
Figure 1. Copper mining and beneficiating model plant.

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CHEMICAL
Figure 2. Iron ore mining and beneficiating model plant.

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CHEMICAL
FLOTATION
Figure 3. Molybdenum mining and beneficiating model plant.

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The gold ore model plant size (Figure 4) was based on the production
figures for only those sites that mine gold as the principal ore: i.e.,
actual gold mines.
The lead/zinc industry model plant size (Figure 5) was based on combined
production levels for the two industries. It is an average of the model
plant sizes for lead and zinc, as determined separately. The lead model
plant size was based on 25 mines producing 99 percent of the Nation's lead,
and the zinc model plant size was based on 25 mines producing 89 percent of
3
the Nation's zinc ore.
The clay model plant size (Figure 7) was determined by two methods.
Mine waste tonnage was calculated as the average of the total mine wastes
produced at all clay mines. Tailings tonnage was calculated as the average
from the production of kaolin and fuller's earth, because these are the
only clay processes that generate significant quantities of tailings.^
The model plant sizes for the remaining industries—phosphate rock
(Figure 6); crushed, broken, and dimension stone (Figure 8); sand and gravel
(Figure 9)--were calculated as an average production size based on the
total number of mine sites within the respective industries.
2. Baseline and Criteria-Induced Control Methods for Tailings and Mine
Wastes at Model Plants
Most mining industries are now using control methods that satisfy at
least some portion of the Federal criteria. These baseline controls are
indicated on the model plant block diagrams for each industry (Figures 1
through 9). The copper, iron ore, gold, lead/zinc, clay, and stone industries
have minimal diversion ditching to prevent surface waters from interacting
with overburden piles. These industries also have minimal closure practices
for overburden, usually involving grading and revegetation. "Minimal"
diversion ditching and closure means that 20 percent (for ditching) and 10
percent (for closure) of the individual facilities within the industry are
using these practices. Diversion ditching and closure of overburden primarily
protect surface water from pollution by suspended solids.
10

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PLACER MINING
OPEN PIT/UNDERGROUND MINING
REAGENTS
HATER	(CYANIDE)
Figure 4. Gold mining and beneficiation model plant.

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ALL VALUES IN DRY METRIC TONS PER YEAR.
Figure 5. Lead/zinc mining and beneficiating model plant.

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Figure 6. Phosphate mining and beneficiating model plant.

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WATER
Figure 7. Clay mining and beneficiating model plant.

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Figure 8. Crushed, broken, and dimension stone mining model plant.

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WATER
Figure 9. Sand and gravel mining model plant.

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The molybdenum industry makes extensive use of diversion ditches, which
are present in about 80 percent of the industry. Both the molybdenum and
phosphate industries commonly grade and revegetate their overburden. Phosphate
mining companies in Florida reclaim all or nearly all of their overburden.
Unlined ponds are the baseline controls used in the two major industries
(clay, sand and gravel) that produce tailings classified as nonhazardous.
In addition to the ponds, the clay industry practices minimal closure for
tailings. The stone industry produces negligible quantities of tailings.
Control methods have also been formulated in response to RCRA. (See
Figures 10 through 15.) These various controls are discussed below in terms
of the criterion to which they apply.
a. Ground Water
Control methods that would meet the RCRA ground-water criterion
(Figure 10) include the construction of diversion ditches to direct water away
from the overburden and waste rock disposal areas. This control reduces the
leaching of materials from these areas and subsequent pollution of the ground
water.
Industries that generate nonhazardous tailings would first evaluate the
water table to determine whether leachate from existing, unlined tailings
ponds could adversely affect the quality of ground water. A high/low water
table has been delineated for this purpose. In a particular industry, the
degree to which the tailings ponds will have an adverse impact on the ground
water depends on the region where the industry is located. This study assumes,
for example, that in the southeastern section of the country 25 percent of the
land has a low water table and 75 percent a high water table; and these
percentages are assumed to be reversed in states in the Southwest. A national
summary of these high/low water-table percentages was prepared for the
Northwest, Southeast, Southwest, Northeast, and Midwest (Table 3).
17

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NONHAZARDOUS WASTES
TAILINGS
MINE WASTES
- DIVERSION DITCHES
GROUND WATER
TABLE
EVALUATION
HIGH
GROUND WATER
TABLE
/
LOW
GROUND WATER
TABLE
\
NOTHING ADDITIONAL
TO SATISFY RCRA CRITERIA
SITE
EVALUATION
INSIGNIFICANT
IMPACT SIGNIFICANT
IMPACT
MONITORING
WELLS
UPGRADE WITH
LEACHATE COLLEC-
TION SYSTEMS
- MONITORING WELLS
Figure 10. Controls induced by RCRA ground-water criterion covering
nonhazardous wastes from the mining industry.
18

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TABLE 3
REGIONAL PERCENTAGES OF LOW OR HIGH WATER TABLE
USED IN ANALYSIS OF GROUND WATER CRITERION
Region
Low water
table (%)
High water
table (%)
Northeast
50
50
Southeast
25
75
Southwest
75
25
Northwest
75
25
Midwest
25
75
Nonhazardous tailings ponds located in areas with low water tables are
assumed to need no additional controls to satisfy the ground-water criterion.
Ponds in areas with high water tables could be subjected to a site evaluation
(consisting of a hydrogeological survey, permeability tests, evaluation, and
report) to determine the actual impact on the ground water. It is estimated
that 80 percent of the site evaluations would show an insignificant impact,
with the accompanying recommendation that monitoring wells should be installed
and data collected quarterly at these sites. The remaining 20 percent of
the evaluations would indicate significant ground-water impact, with the
recommendation that these sites install further control measures. The controls
would consist of collection wells for the leachate to prevent it from
entering the ground water. In addition, monitoring wells would be installed
in appropriate locations to perform quarterly checks of the leachate collection
system.
b. Surface Water
Control methods to meet the RCRA surface water criterion are shown
in Figure 11. Diversion ditches around mine waste piles would prevent surface
runoff from interacting with the waste and carrying it, primarily as suspended
solids, into surface waters. The tailings ponds is a baseline control method
for nearly all mining industries; it contains the tailings and prevents surface
water contamination. One exception to the use of tailings ponds is gold
19

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placer mining operations, which are primarily located in Alaska and California.
Sluiced wastes (tailings) from these operations are the only nonhazardous
tailings within the gold mining and beneficiating industry. In current
practice, they are pumped directly to streams and rivers. Control of the
tailings from gold sluicing operations could be accomplished by construction
of tailings ponds.
NONHAZARDOUS
WASTES
-	DIVERSION DITCHES	- DIVERSION DITCHES
-	COMPACTION OF DIKE
-	SOIL COVERAGE OF DIKE
-	REVEGETATION OF DIKE
Figure 11. Controls induced by RCRA surface water criterion covering
nonhazardous wastes from the mining industry.
For industries having tailings ponds, further controls to meet the surface
water criterion include diversion ditches and upgrading of the pond dikes by
compaction, soil coverage, and revegetation. The diversion ditches would
direct waters away from tailings ponds to prevent the dikes from being
weakened or washed out; and to reduce the chances of pond overflow. Either
condition could cause suspended solids to contaminate surface waters.
c. Wetlands
Control methods to meet the RCRA wetland criterion are shown in
Figure 12. Two scenarios are considered for tailings and other mine wastes.
One scenario assumes that NPDES permits will be granted to all mining industries
located in wetlands, allowing solid wastes to be disposed of within the area.
The second scenario assumes that no NPDES permits will be granted and that all
20

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NONHAZARDOUS
WASTES
TAILINGS
MINE WASTES
NPDES PERMIT APPLICATION
DENIED
/
GRANTED
\
NPDES PERMIT APPLICATION
DENIED
GRANTED
/
\
CLOSURE OF EXISTING
TAILINGS POND [REQUIRES
ADDITIONAL MEASURES
(FIG. 16)]
ACQUISITION OF LAND
ANO CONSTRUCTION OF
A NEW DISPOSAL FACILITY
OUTSIDE WETLANDS AREA
UPGRADE DIKE	-	ACQUISITION OF LANO ANO
COMPACTION OF DIKE	CONSTRUCTION OF A NEW
SOIL COVERAGE OF DIKE	DISPOSAL FACILITY OUT-
REVEGETATION OF DIKE	SIDE WETLAND AREA
- MONITORING WELLS
- TRANSPORTATION OF WASTES
TO NEW DISPOSAL AREA
TRANSPORTION OF WASTES
TO NEW DISPOSAL AREA
Figure 12. Controls induced by RCRA wetland crierion covering
nonhazardous wastes from the mining industry.

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mining wastes generated in wetlands will have to be transported out of the
area. Control methods for the two scenarios are outlined in the following
paragraphs:
NPDES permits granted: Monitoring wells, checked on a quarterly basis,
would be installed around mine waste piles as a precautionary measure. The
dikes around tailings ponds would be upgraded into a 3:1 sloped structure (3
horizontal, 1 vertical). This control would also include dike compaction,
soil coverage, and revegetation (similar to the controls for the surface water
criterion).
NPDES permits denied: This scenario would involve the purchase of land
outside the wetlands to construct disposal facilities for tailings and mine
wastes. The control system would include the transportation of these
nonhazardous wastes to the new sites. With one exception, it is assumed that
the wastes from all mining industries located in wetlands would have to be
trucked a distance of 16 kilometers one way. The exception is the Florida
phosphate industry, which is located in areas of extensive wetlands; the assumed
trucking distance in this case is 32 kilometers.
Because of the distances involved, pumping the tailings to the new
facility is not considered feasible. The control method described here includes
thickening the tailings slurry to a 70 percent solids sludge before it is
transported by truck. Overflow from the centrifuge would be pumped to storage
tanks as recycle water.
In addition to trucking the newly generated tailings to new disposal
facilities that meet RCRA criteria, the scenario includes closing the existing
tailings ponds (pond free water pumped off, pond allowed to drain, 0.6 meters
of soil uniformly graded over the pond, and revegetation). Closure measures
for the relocated disposal facilities are described under the closure
criterion.
The percentages of the specific industries located in wetlands were
calculated from the percentages presented in Table 13 (page 111-6) of the
22

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Draft EIS; and from knowledge of the relative locations of these wetlands and
the minerals industry facilities when this information was available. For
example, although 46 percent of Florida is wetlands, most of the Florida
phosphate industry is located within that portion; so a value of 90 percent
was assumed to represent this case.
d. Floodplains
Control methods to meet the RCRA floodplains criterion are shown in
Figure 13. Diking is the principal method selected, for both tailings and
mine wastes, to satisfy this criterion. For mine wastes, this entails
construction, compaction, soil coverage, and revegetation of dikes 3 meters
high at a 3:1 slope. The dikes would be built around accumulated plus newly
generated mine waste. On a national average, three sides of the mine waste
piles (assuming roughly rectangular shapes) would require diking. In actuality,
some waste piles are located against a ridge or ridges bordering the
floodplains; these piles may be protected from floods on one, two, or three
sides. Conversely, some waste piles are located in the middle of floodplains,
and dikes would have to be built around their entire periphery.
For tailings ponds, the floodplain criterion would include upgrading
the pond dikes to a 3:1 slope, compacting, covering with 0.6 meters of soil,
and seeding and fertilizing to prevent erosion.
I
NONHAZARDOUS WASTES
(TAILINGS AND MINE WASTES)
-	DIKE CONSTRUCTION
-	COMPACTION OF DIKE
-	SOIL COVERAGE OF DIKE
-	REVEGETATION OF DIKE
Figure 13. Controls induced by RCRA floodplain criterion covering
nonhazardous wastes from the mining industry.
23

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The percentages of industries located in floodplains were determined on
a state-by-state basis. Most of the states were assigned a value of 5 percent,
which is the estimated average percentage of land in the United States that
is within floodplains.
Air Quality
Control methods to prevent adverse impacts on air quality are shown
in Figure 14. Fugitive dust from mine waste piles would be controlled by
revegetating the piles. This method is discussed under the closure section.
NONHAZARDOUS WASTES
TAILINGS
MINE WASTES
KEEPING FREE
WATER ON THE
ENTIRE PORTION
OF THE TAILINGS
POND
NO CONTROLS NEEDED DURING
ACTIVE DISPOSAL OF MINE
WASTES. CLOSURE CRITERIA-
INDUCED CONTROLS PROVIDE
FOR LONG TERM PROTECTION
OF AIR QUALITY
Figure 14. Controls induced by RCRA air quality criterion covering
nonhazardous wastes from the mining industry.
Fugitive dust can also be generated by the action of the wind across
dried areas of tailings ponds, particularly in arid regions of the West and
Southwest. Tailings that are considered nonhazardous, such as those of the
clay and sand and gravel industries, are contained in ponds that are smaller
in size and are nearly all located in nonarid regions. As a result, the
pond surfaces are wet most of the time (i.e., the addition of new tailings
water and the precipitation rate exceed the evapotranspiration rate for these
areas). Because the ponds do not dry out and create dust problems, no additional
controls to protect air quality standards are considered necessary.
24

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f. Closure
Control methods to meet the RCRA closure criterion are shown in
Figure 15. The RCRA criterion requires that accumulated and newly generated,
nonhazardous mine wastes be closed with 0.6 meters of soil cover, and that
the soil be revegetated. With a few exceptions, such as Florida phosphate,
most of the mineral industries have allowed mine wastes to accumulate in
piles since the startup of the mines. The quantity of these wastes is
considerable, depending on the type of industry and length of time the
mines have been in operation; the copper model plant, for example, has an
assumed life of 15 years. The control method for stabilizing these accumulated
mine waste piles would involve regrading to provide adequately contoured
slopes; compaction of this material; coverage with 0.6 meters of soil; soil
amelioration; and seeding to revegetate.
NONHAZARDOUS WASTES
TAILINGS
MINE WASTES
DEWATERING
SOIL COVERAGE
RE VEGETATION
-	GRADING AND SURFACE COMPACTION
-	SOIL COVERAGE
-	REVEGETATION
Fiaure 15 Controls induced by RCRA closure criterion covering
nonhazardous wastes from the mining industry.
The newly generated mine wastes would be spread out, compacted, covered
with soil, and revegetated on a continual basis. These procedures are similar
to the reclamation that is practiced in some industries. Closure would thus
occur regularly, so that the wastes would be "closed" on a weekly, monthly,
or even an annual basis rather than be allowed to accumulate through the
remainder of the mine life.
25

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Procedures for closure of a tailings pond when it is full are also shown
in Figure 15. Pond free water would be pumped to a pressurized filtering
system to remove solids, and the clarified water would be discharged to a
surface stream or river or used for operational purposes at the mine or mill.
When the drained area was stable, 0.6 meter of soil would be used to cover
the tailings, followed by compaction and revegetation.
3. Costs and Cost Methodology
This section presents and discusses baseline costs, state- and other
Federal-induced costs, and Criteria-induced costs on a capital and an
annualized basis. All the costs are given in 1978 dollars. The methodology
used to determine these costs is also discussed. The two principal sources
of cost data were Richardson and Means; other sources were used for certain
unit costs.5*8
a.	Baseline and Above-Baseline Costs
For each of the 10 mining industries, costs have been calculated
for the baseline case and for the control methods attributable to government
regulations (Table 4). Baseline costs include all the criteria; costs above
baseline are figured separately for each criterion. In the copper industry,
for example, the 61 mines have a total baseline capital cost (for all criteria)
of $94,000; annual operating and maintenance costs are $3,216,000; and total
annualized costs are $3,227,000. Capital costs above baseline to meet the
ground-water criterion are estimated at $185,000, and total annualized costs
are estimated at $37,000. Within this industry, the sum of the costs above
baseline to meet all criteria is estimated at $433 million, and total annualized
costs at $114 million.
b.	Costs Per Unit of Waste and Product
The control method costs have also been calculated per metric ton
of waste and of product, based on the total annualized costs for each industry
(Table 5). For the baseline case, these costs in the copper industry are
26

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TABLE 4
ESTIMATED TOTAL BASELINF AND GOVFRNMFNT-TNDUCFD COSTS BY INDUSTRY AND BY CRITERION
(1,000 dollars)
!\>
-VI
Costs attributable to government regulations (above baseline)
Wet lands
Mining industry
Copper
Total capital
Annual OtM
Total annualized
iron ore
Total capital
Annual OfcK
Total annualized
Molybdenum
Total capital
Annual otM
Total annualized
Gold
Total capital
Annual OtM
Total annualized
Lead/zinc
Total capital
Annual OtH
Total annualized
Phosphate
Total capital
Annual OtM
Total annualized
Baseline
costs
Ground
water
Surface
water
NPDES
permit
granted
Nl'DES
permit
denied
Floodplains
Closure
NPDES
permit
granted
Total
NPDES
permit
denied
94
3,21*
3,227
134
2,408
2,424
1,960
1,100
1,340
6
91
91
26
99
104
59
9, 292
9,292
IBS
10
37
264
14
SO
1,947
208
628
52
4
13
119
7
28
185
10
37
264
14
50
5,286
265
1,042
52
4
13
119
7
28
120
19
35
13
4
4
26,700
15,800
19,200
30
30
35
1,219 112,900
174 238,400
390 258,000
,500
224
823
1,044
54
110
419
22
95
2,828
141
650
433,000
50,540
114,000
430,000
43,000
100,700
11,600
580
2,000
13,770
1,400
3,420
8,742
1,313
2,863
63,700
9,600
20,800
433,370
50,560
114,074
435,148 461,728
43,271 59,052
101,658 120,823
11,606
582
2,002
22,047
1,927
5,200
9,278
1,347
2,988
9,295
1,373
3,019
67,985 179,666
9,929 240,155
29,896 279*506
Clay
Total capital	46,800	9,109	4,003	22,720	16,320
Annual OtM	15,180	923	201	598	2,977
Total annualized	22,050	2,861	1,040	1,793	5,743
7,891 107,700 151,423 145,023
397	4,366	6,485 8,864
2,0*0	26,940	34,684 30,634
Stone
Total capital	1,300	2,500	2,500	14,130	10,640
Annual OtM	2,693	125	125	1,063	5,000
Total annualized	2,027	650	650	4,909	7,200
16,350 180,000 215,480 212,190
822	34,000	36,935 40,072
4,250 72,000 82,459 84,750
Sand and gravel
Total capital	401,900	310,800	87,970	13,860	60,590
Annual OtM	17,800	34,300	4,399	693	3,030
Total annualized	93,600	101,100	28,800	4,536	15,530
345,100 421,800 1,179,530 1,226,260
17,300	56,692 59,029
113,000 117,000 364,436 375,430
Other
Total capital	45,200	32,500	10,040	5,206	22,740
Annual OtM	5,187	3,560	503	335	26,540
Total annualized	13,500	10,540	3,166	1,167	30,570
37,810 167,000 252,556 270,090
1,896	14,500	20,794 46,999
12,100	45,970	72,943 102,346
Total
Total capital	497,479	357,479	110,422	57,268	250,120
Annual OtM	57,056	39,152	5,529	3,686 291,777
Total annualized	148,455	115,908	34,827	12,834	336,278
415,942
20,856
133,078
1,837,312
159,299
505,693
2,778,423 2,971,275
228,522 516,613
802,340 1,125,784

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TABLE 5
ESTIMATED BASELINE AND REGULATORY COSTS PER UNIT BASIS

*
Current product value
(S/metric ton)

Baseline costs

Mining industry
National
annualized costs
($1000/yr)
$/metric
ton of waste
$/metric
ton of product
Copper
1,325
3,227
0.005
0.013
Iron ore
24.70+ and 0.675
2,424
0.010
0.011
Molybdenum
10,990'
1,340
0.125
24.4
Gold
6,77O,OOO0
91
0.011
4,330
Lead/Zinc
Lead, 747; Zinc, 681
104
0.022
0.006
Phosphate
17.40
9,292
0.062
0.055
Clay
2.20 to 220**
22,050
0.612
0.554
Stone
2.85++
2,827
0.043
0.003
Sand and gravel
2.46
93,600
2.61
0.130
*
1978 dollars; 1979 Mineral Commodity Summaries, U.S. Bureau of Mines
^Natural ores, 51.5% Fe.
I
Pellets, per metric ton unit of Fe.
'per ton of molybdenum in concentrate.
^Based on average selling price of $192.50/oz.
**
Price varies with type and quality of clay.
4.x
Dimension stone at $89.80/metric ton accounts for 0.15% of stone production.
(continued)

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TABLE 5 (continued)
State-and other Federal-	State-and other Federal-induced costs
induced costs (NPDES permit granted)		(NPDES permit denied)	
National	National
Mining industry
annualized costs
(SlOOO/yr)
$/metric ton
of waste
$/metric ton
of product
annualized costs
<$1000/yr>
$/metric ton
of waste
$/metr ic ton
of product
Copper
69
0.0001
0.0003
69
0.0001
0.0003
Iron ore
829
0.004
0.004
12,500
0.05
0.05
Molybdenum
1
0.0001
0.02
1
0.0001
0.02
Gold
1,745
0.21
83,100
1,723
0.20
83,320
Lead/Zinc
99
0.02
0.006
31
0.007
0.002
Phosphate
704
0.005
0.004
159,400
1.06
0.95
Clay
5,640
0.16
0.14
10,500
0.29
0.24
Stone
4,565
0.07
0.006
11,100
0.16
0.01
Sand and gravel
169,300
4.72
0.24
183,300
5.1
0.26
(continued)

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TABLE 5 (continued)
Criteria-induced costs Criteria-induced cost
(HPDES permit granted)	 		(NPDES permit denied)
Mining industry
National
annualized costs
($1000/yr)
$/metric ton
of waste
$/metrie ton
of product
National
annualized costs
($1000/yr)
$/metric ton
of waste
$/metric ton
or product
Copper
114,200
0.18
0.47
114,200
0.18
0.47
Iron ore
100,800
0.43
0.46
100,800
0.43
0.46
Molybdenum
2,000
0.19
36.3
2,000
0.19
36.3
Gold
3,574
0.42
170,200
3,574
0.42
170,200
Lead/Zinc
3,020
0.63
0.18
3,020
0.63
0.18
Phosphate
21,210
0.14
0.13
20,800
0.14
0.12
Clay
29,150
0.81
0.73
28, 200
0.71
0.71
Stone
77,710
1.18
o
o
7 3,960
1.12
0.09
Sand and gravel
199,500
5.56
0. 28
196,450
5.47
0.27

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estimated at $3.2 million; this figure equals $0,005 per metric ton of waste
and $0,013 per metric ton of product. For state- and other Federal-induced
annualized costs (NPDES permit granted), the estimate is $69,000; this figure
equals $0.0001 per metric ton of waste and $0.0003 per metric ton of product.
For Criteria-induced annualized costs (NPDES permit granted), the estimate is
$114 million; this figure equals $0.18 per metric ton of waste and $0.47 per
metric ton of product.
c, Cost Methodology
(1) Capital Costs
National baseline and above-baseline capital costs for each
mining industry were based on the size of the model plant and the control
methods chosen to meet the RCRA criteria. Unit costs were determined for
components of control methods that are current or baseline and those that are
above baseline to provide compliance with RCRA. The baseline and above-
baseline control method component costs were subsequently calculated for the
model plants. The sum of the control costs to meet a criterion for a model
Plant was then calculated, as applicable, for tailings and mine wastes. These
costs were determined for each of the six criteria for each model plant. When
one control strategy satisfied two criteria, such as surface water and ground
water, the costs for the strategy were divided equally between them.
In each industry, the baseline costs to meet all criteria were determined
from the product of the number of model plants and the sum of the model plant
control costs. The total baseline costs per criterion were determined from
the product of the number of model plants in the industry and the model plant
cost of meeting that criterion. The individual industry criterion costs were
summed to get the total mining industry criterion costs.
The criterion costs were used to develop the baseline and above-baseline
costs by state. The number of model plants in each state by industry and
31

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by type of waste (tailings and mine wastes) were determined by proportioning
total tailings and mine waste quantities among the states, based on industry
production figures For each state, the cost increment was determined from
the product of number of model plants per industry and the model plant
control costs for a criterion. The sum of these incremental costs for all
industries within a particular state is that state's total industry cost to
meet one RCRA criterion. The sum of these costs for all states in the
United States is the national mining industry's cost to meet a criterion;
and the sum of these costs for all criteria is the national cost impact on
the mining industry of meeting RCRA-level controls for nonhazardous wastes.
A contingency factor of 20 percent is included with the capital costs
shown in the tables.
Costs of RCRA-level controls were calculated by state to determine the
total state-induced costs. Control costs in each state having regulations
equivalent to the RCRA criteria were added together, then deducted from the
national total costs of RCRA-level controls. The matrix shown in another
appendix (Economic Impact Analysis) to this document lists the states that
have regulations equivalent to RCRA criteria. Other Federal-induced costs
(in Table 2, and included in above-baseline costs In Tables 4 and 5) are those
attributable to the Clean Water Act. They represent the controls installed to
meet the surface water and wetlands criteria (NPDES permit denied) in the states
that do not have equivalent regulations. State and other Federal-induced costs
are combined and deducted from the costs of meeting RCRA-level controls to
yield the actual Criteria-induced cost.
(2) flnnuaTized Capital Costs and Trust Funds
Annualized capital costs were determined for each industry by
» *• ¦ 4.U ,.anitsl at 12 percent interest over the remaining life of the
amortizing the capital at i<-
model plant. The equation for determining the annuity or capital recovery
factor is:
LLP + i )nl ,
[(i + in - l]
32

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where i is the interest rate and n is the number of years. Annuity factors
for the main industries considered in this study are shown in Table 6.
TABLE 6
ANNUITY FACTORS FOR MAJOR MINING INDUSTRIES
WITH NONHAZARDOUS WASTES
Industry
Assumed remaining life of
model plant (years)*
Annuity factor
Copper, gold
15
0.1468
Iron ore
20
0.1339
Molybdenum
30
0.1241
Lead/zinc, phosphate
10
0.1770
Clay, stone
7.5
0.2096
Sand and gravel
5
0.2774
* These remaining lives are assumed to be half of the full lives.
Another annualized capital cost is the establishment of trust funds to
pay for the closure of tailings ponds at the end of a mining operation and the
operation and maintenance of monitoring wells after closure. A closure
period of 1 year was assumed for nonhazardous tailings ponds (dewatering,
adding soil, and revegetating). The trust fund for the monitoring wells is
based on the assumption that they will be operated and maintained for 5 years
after closure. Equations were derived to determine the trust funds for
closure and for the monitoring wells (Table 7). The equations take into
account variations in remaining life among the model plants, and they include
a 2 percent return (above inflation) on capital. In the equations, T is the
capital cost of the trust fund; and S is the cost of closure and of well
operation and maintenance for 1 year.
33

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TABLE 7
EQUATION FOR TRUST FUNDS
Industry	Tailings pond closure	Monitoring well upkeep
Iron ore	T = 3.202 S
Lead/zinc, phosphate	T = 3.903 S
Clay, stone	T = 0.853 S	T = 4.101 S
Sand and gravel	T = 0.897 S	T = 4.309 S
(3) Other Annual Costs
In addition to annualized capital costs, the other annual costs
include maintenance of the various control systems (assumed to be 5 percent
of the applicable total capital costs); electricity to operate pumps, as
during pond dewatering (assumed to cost 30 mills/kWh); labor to operate
equipment, such as the front-end loader, is costed at $26.60 per man-hour,
including supervision and overhead; trucking of tailings and mine wastes
from wetlands when NPDES permits are denied (assumed to be done by a contractor);
and annual costs of continuous overburden grading, soil spreading, and
revegetating, (also assumed to be done by a contractor).
d. Configuration and Costs of Control Methods
The flow diagrams (Figures 1 through 9) and "tree" diagrams (Figures
10 through 15) in Sections 1 and 2 presented the different baseline controls
and those that would meet RCRA criteria, respectively. This section discusses
design parameters and components of the control methods. Unit costs are
listed, where appropriate, in parentheses.
(1) Tailings Pond
The tailings pond is the principal method used to control
mining beneficiation wastes. Most mines have tailings ponds; some, such as
gold placer mines, discharge their waste sluicing water elsewhere. To
34

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determine the cost of constructing a tailings pond for nonhazardous beneficia-
tion wastes, this study assumed the following design parameters: rectangular-
shaped pond; depth of about 11 meters from the top of the dike to the bottom
of the pond; dike around three sides of the pond (assuming a natural barrier
on one side); and a slope of 2:1 (horizontal:vertical) except in floodplains
or wetlands, where dikes are sloped 3:1. The dikes are constructed to have a
6-meter wide horizontal section along the top so that machinery can be driven
and maneuvered there. Ponds are designed with a 1.5 meter freeboard above
the water and an allowance of 1.2 meters of free water above the settled
solids. Incoming slurry is assumed to be 30 percent solids, by weight; and
settled tailings are assumed to be 65 percent solids, with an average specific
gravity of 1.8. The excavated depth of a pond is based on the amount of
material needed to construct the dike. The length to width ratio of the pond
is 2:1.
With the exception of the sand and gravel industry, it is assumed that
one pond will accomodate the beneficiation (tailings) wastes from the other
subject mineral industries over the entire life of each model plant. Sand
and gravel operations typically construct a small settling pond at the start-
up of a mine to receive beneficiation wastes during the initial two or three
years of operation; with subsequent employment of one or more excavated areas
from the mining operation for this purpose; consequently, baseline control
costs for tailings from the sand and gravel industry are based on this
configuration, i.e., construction of a 3-year settling pond and operation and
maintenance of this pond and the ponds created by the mining operation over
the life of the mine. In a case where a new pond must be built (e.g., gold
placer mining) the cost is calculated for a capacity adequate to handle
tailings for half the duration of a mine life; it is assumed that the mines
are halfway through their useful lives. For both baseline case ponds and new
ponds, assumptions about the annual quantities of tailings received were
shown in Table 1.
The capital cost of constructing a tailings pond includes the following
components: land (rural undeveloped, $2,400 per hectare); land clearing
($1,300 per hectare); survey ($925 per hectare); excavation of pond area
35

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($0.47 per cubic meter); hauling and dumping overburden at the dike area
($0.47 per cubic meter); dike formation and compaction ($1.88 per cubic
meter); and fine grading ($0.69 per square meter).
(2)	Ground Mater Evaluation
This evaluation is the determination of the water table level.
The main costs are for drilling temporary test wells,; which in this study are
assumed to be 6.35 centimeters in diameter. The cost of a 15-meter-deep well
is $475, and each linear meter exceeding that depth is $25.
(3)	Site Evaluation
A detailed site evaluation includes a hydrogeological survey
to determine ground-water movement and flow nets ($5,000), and tests of
borings to determine Teachability and permeability ($3,000). Capital costs
of such an evaluation, including engineering appraisal and a report, is
estimated at $15,000.
(4)	Leachate Collection System
The system considered here is a group of collection wells
spaced at a density of one per hectare. Each well is equipped with piping
and a pump located above ground level. The wells collect the leachate and
pump it back to the tailings pond. Cost of a well, with pump and piping, is
estimated at $4,500.
(5)	Monitoring Wells
The monitoring wells are costed according to depth. The wells
include casing 10 centimeters in diameter, schedule 40 piping 3.8 centimeters
in diameter, and pumps rated at 5,700 liters per hour. The installed cost of
a 15-meter deep monitoring well is estimated at $3,000; and a 30-meter-deep
well, at $4,000.
36

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(6) Diversion Ditches
Cost of construction of diversion ditches (1.8 meters deep by
0.6 meters wide at the top) with a trencher is approximately $2.10 per linear
meter.
(7) Dike Formation, Soil Coverage, Revegetation
Dikes are the principal control method used in this study for
protecting overburden in floodplains. They are also part of the construction
of a tailings pond, when no natural barriers are available. In this study,
tailings pond costs normally include dikes with 2:1 slopes (which are assumed
to exist at all baseline case ponds). Costs of dikes for new ponds are
attributable to RCRA, as are the costs of new dikes (3:1 slopes) around
overburden in floodplains, and for modifying existing pond dikes in wetlands
and floodplains to 3:1 slopes.
Unit construction costs used for dike construction and compaction were:
$1.26 per cubic meter of dike material to build a floodplain dike around mine
wastes (3:1 slopes, 3 meters high, constructed of overburden); and $1.88 per
cubic meter to build a tailings pond dike (2:1 slope). The unit cost of dike
formation for tailings ponds is based on the baseline case, which includes
the cost of fine grading the dike.
Additional costs of $0.51 per cubic meter of dike material are needed to
modify pond dikes in floodplains from a 2:1 to a 3:1 slope. These costs are
for loading trucks and hauling overburden from the piles to the dike areas.
Additional costs of $0.47 per cubic meter are needed for new tailings pond
dikes not in floodplain areas. These costs are for hauling and dumping the
excavated portion of the pond to the dike area.
The revegetation costs for dikes or for closing tailings ponds and mine
waste piles include the cost of fill soil, top soil, seeding, and fertilizing.
It was assumed that all of the soil would have to be purchased. When mine
wastes are revegetated as an ongoing procedure (e.g., in the Florida phosphate
37

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industry), it is assumed that usable soil material could be segregated during
mining operations so that only 50 percent of the soil would need 'to be
purchased.
Unit costs of soils and revegetation used in this study are as follows:
purchased fill soil (0.45 meters thick) is $3.40 per cubic meter delivered to
dike areas, and $23,500 per hectare delivered to overburden piles and tailings
ponds for closure; purchased top soil (0.15 meters thick) is $4.12 per cubic
meter delivered to dike areas, and $8,800 per hectare delivered to the site
for closure purposes. The surface areas used to determine costs, by industry,
are shown in Table 8.
Where only the outer slope and horizontal portion of the dike are covered
with fill soil and top soil, costs of spreading and compacting the two soils
are $1.26 and $1.53 per cubic meter, respectively. The costs increase by
fifty percent if both slopes (as on floodplain dikes) are covered with soil.
Fine grading of the soil on dikes is costed at $0.69 per square meter.
Revegetating, including seed and fertilizer, is costed at $2,500 per hectare.
This revegetation cost applies to dikes and the closure of tailings and mine
wastes.
(8) Waste Transportation
If NPDES permits are not granted to mines in wetlands, costs
must be included for transporting newly generated mining wastes out of those
areas. Capital costs include purchasing a front-end loader to load the newly
generated mine waste from the piles onto 30-ton trucks. If the front-end
loader is used full time for 8 hours a day, 5 days a week, 50 weeks a year,
the cost of the equipment per hour is estimated at $52. Trucking of the
waste from the mine site to the disposal facility is assumed to be done by a
contractor, which makes it an operating cost. The unit cost of trucking is
$1.05 per metric ton of waste, including fuel and labor and based on a round
trip of 32 kilometers. This distance was assumed for all mines in wetlands
except the Florida phosphate industry, which is located in extensive wetlands
38

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TABLE 8
SURFACE AREAS OF NONHAZARDOUS
MINING WASTES BY INDUSTRY MODEL PLANT
Industry
Full
1 i fe*
Mine
wastes
(hectares)
Tailings
pond
(hectares)
Copper
716
NA+
Iron
355
NA
Molybdenum
5.28
NA
Gold
153
0.5§
Lead/zinc
7.73
NA
Phosphate
171
NA
Clay
1.67
2.3
Stone
1.42
Negligible
Sand and Gravel
Negligible
0.8
Urani urn
NA
NA
* For model plant half life, values are half the number shown.
+ Not applicable; wastes are considered hazardous.
§ Only tailings wastes from mining of placer deposits.
39

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areas. A distance of 64 kilometers was assumed there, bringing the unit cost
of trucking to an estimated $1.96 per metric ton of waste.
Other operating costs include labor and fuel to operate the front-end
loader. Direct labor plus overhead is estimated at $26.60 per man-hour, and
fuel at $6.00 per hour per loader (38 liters of fuel per hour at $0.16 a
liter).
The capital costs of transporting tailings wastes include such major
items as purchase of a centrifuge (to concentrate the slurry from 30 percent
solids to 70 percent solids); a slurry feed pump plus spare; sludge conveying
system/hopper; and recycle water tanks. The sum of these items for the clay
industry model plant, for example, is about $205,000.
(9) Dewatering Tailings Pond for Closure
In this study, dewatering consists of pumping the free water
off the tailings pond and allowing the retained surface water to drain until
the ground is stable enough for machinery to work on it. The costs include
pumping the water from the pond surface and purchase of a fine-mesh, backwash
filter to remove suspended solids. The capital cost of the filtering unit,
with pumps and piping, is $25,000. The main operating cost is for electricity
(30 mills per kilowatthour) to run the centrifugal feed and backwash pumps.
40

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REFERENCES
1.	U.S. Bureau of Mines. Minerals yearbook 7974. v. 1. Metals, minerals
and fuels. U.S. Department of the Interior, 1976.	'
2.	PEDCo Environmental, Inc. Study of adverse effects of solid wastes from
all mining activities on the environment. U.S. Environmental Protection
Agency. Contract Number 68-01-4700. Cincinnati, 1979. 303 p.
3.	U.S. Bureau of Mines. Mineral commodity summaries 1978. U.S. Department
of the Interior, 1978. 200 p.
4.	U.S. Bureau of Mines. Mineral facts and problems. Bulletin 667. U.S.
Department of the Interior, 1975. 1,266 p.
5.	Richardson Engineering Services, Inc. The Richardson rapid system.
1978-79 ed. v. 1, 3, 4. Solano Beach, Calif., 1978.
6.	Robert Snow Means Company, Inc. Building construction cost data, 1978.
Duxbury, Mass., 1977.
7.	U.S. Environmental Protection Agency. Assessment of industrial hazardous
waste practices in the metal smelting and refining industry. SW-145c. 2.
Washington, D.C., 1977.
8.	Midwest Research Institute. A study of waste generation, treatment and
disposal in the metals mining industry. PB-261052. Environmental
Protection Agency, Washington, D.C., October 1976.
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