EPA 440/l-75/059b
GROUP II,
D evelopment Document for
Interim Final Effluent Limitations Guidelines
and New Source Performance Standards
for the
MINERALS FOR THE CHEMICAL AND
FERTILIZER INDUSTRIES
VOL. II
MINERAL MINING AND
PROCESSING INDUSTRY
Point Source Category
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
OCTOBER 1975

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DEVELOPMENT DOCUMENT
for
INTERIM FINAL
EFFLUENT LIMITATIONS GUIDELINES
and
STANDARDS OF PERFORMANCE
MINERAL MINING AND PROCESSING INDUSTRY
VOLUME II
Minerals for the Chemical and Fertilizer Industries
Russell E. Train
Administrator
Andrew W. Breidenbach, Ph.D.
Acting Assistant Administrator for
Water and Hazardous Materials
Eckardt C. Beck
Deputy Assistant Administrator for
Water Planning and Standards
^tDSX
1532
Allen Cywin
Director, Effluent Guidelines Division
Michael W. Kosakowski
Project Officer
October 1975
Effluent Guidelines Division
Office of Water and Hazardous Materials
U.S. Environmental Protection Agency
Washington, D.C. 20460

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ABSTRACT
This document presents the findings of an extensive study of
selected minerals for the chemical and fertilizer industries
segment of the mineral mining industry for the purpose of
developing effluent limitations guidelines for existing
point sources and standards of performance and pretreatment
standards for new sources, to implement sections 301, 304,
306 and 307 of the Federal Water Pollution Control Act, as
amended (33 U.S.C. 1551, 1314, and 1316, 86 Stat. 816 et.
seq.) (the "Act").
Effluent limitations guidelines contained herein set forth
the degree of effluent reduction attainable through the
application of the best practicable control technology
currently available (BPCTCA) and the degree of effluent
reduction attainable through the application of the best
available technology economically achievable (BATEA) which
must be achieved by existing point sources by July 1, 1977
and July 1, 1983, respectively. The standards of
performance (NSPS) and pretreatment standards for new
sources contained herein set forth the degree of effluent
reduction which is achievable through the application of the
best available demonstrated control technology, processes,
operating methods, or other alternatives.
Based on the application of best practicable technology
currently available, 7 of the 12 production subcategories
(comprising 12 minerals) under study can be operated with no
discharge of process generated waste water pollutants to
navigable waters under normal operating conditions. With
the best available technology economically achievable, 7 of
the 12 production subcategories can be operated with no
discharge of process generated waste water pollutants to
navigable waters under normal operating conditions. No
discharge of process generated waste water pollutants to
navigable waters is achievable as a new source performance
standard for all production subcategories except fluorspar
(flotation), phosphate rock (flotation), rock salt, sulfur
(salt dome), and lithium minerals.
Supporting data and rationale for development of the
proposed effluent limtations guidelines and standards of
performance are contained in this report.
i

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CONTENTS
Section	Page
Abstract	i
I	Conclusions	1
II	Recommendations	3
III	Introduction	5
IV	Industry Categorization	37
V	Water Use and Waste Characterization	41
VI	selection of Pollutant Parameters	141
VII	Control and Treatment Technology	149
VIII	Cost Energy and Non-Water Quality Aspects	187
IX	Effluent Reduction Attainable Through the	237
Application of the Best Practicable Control
Technology Currently Available
X	Effluent Reduction Attainable Through	251
Application of the Best Available
Technology Economically Achievable
XI	New Source Performance Standards and	259
Pretreatment Standards
XII	Acknowledgements	265
XIII	References	267
XIV	Glossary	271
ill

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LIST OF FIGURES
Figure

Page
1
Barite Processing Facilities
14
2
Fluorspar Deposits
18
3
Potash Deposits
19
4
Borate Operations
20
5
Lithium, Calcium and Magnesium
22
6
Rock Salt Mines and Wells
28
7
Phosphate Mining and Processing Locations
30
8
Sulfur Deposts
33
9
Barite Mining and Processing
45

(Dry Grinding Process)

10
Barite Mining and Processing
47

(Wet Process)

11
Barite Mining and Processing
51

(Flotation Process)

12
Fluorspar Mining and Processing
58

(HMS Process)

13
Fluorspar Mining and Processing
61

Flotation Process)

14
Minerals Recovery from Searles Lake
70
15
Minerals Recovery at Great Salt Lake
73
16
Lithium Salt Recovery Natural Brine,
76

Silver Peak Operations

17
Borate Mining and Processing
78
18
Potassium Chloride Mining and Processing
82
19
Langbeinite Mining and Processing
83
20
Potash Recovery by solution Mining of
87

Sylvinite

21
Trona Ore Processing by the Monohydrate
90

Process

22
Trona Ore Processing by the Sesquicarbonate
91

Process

23
Sodium Sulfate from Brine wells
96
24
Rock Salt Mining and Processing
99
25
Phosphate Mining and Processing (Eastern)
106
26
Normal distribution of log TSS for a
111

phosphate slime pond discharge

27
Phosphate Mining and Processing (Western)
115
28
Sulfur Mining and Processing (Frasch Process)
120
29
Mineral Pigments Mining and Processing
133
30
Spodumene Mining and Processing (Flotation
136

Process)

31
settling Pond Performance Distribution of
172

Values from Industry Segment

32
Calcium Phosphate Solubility as a
176

Function of pH

33
Bleedwater Treating Facility Type 1
180
34
Bleedwater Treating Facility Type 2
181
v

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1
2
3
H
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Page
4
9
13
39
131
170
183
189
196
198
201
203
206
208
209
212
216
220
222
225
227
229
232
234
278
LIST OF TABLES
Recommended limits and standards for the
Mineral Mining and Processing Industry
Data Base
Production and Employment
Industry Categorization
Sulfur Facilities, Comparison of Discharges
settling Pond Performance
Summary of Technology Applications,
Limitations and Reliability
Capital Investment and Energy Consumption
of Present Waste Water Treatment Facilities
Cost for a Representative Facility
(Barite, Wet Process)
Cost for a Representative Facility
(Barite, Flotation Process)
Cost for a Representative Facility
(Fluorspar, HMS Process)
Cost for a Representative Facility
(Fluorspar, Flotation Process)
Cost for a Representative Facility
(Borates)
Cost for a Representative Facility
(Potash, Carlsbad Operations)
Cost for a Representative Facility
(Potash, Moab Operations)
Cost for a Representative Facility
(Trona ore Mining)
Cost for a Representative Facility
(Rock Salt)
Cost for a Representative Facility
(Phosphate Rock, Eastern)
Cost for a Representative Facility
(Phosphate Rock, Western)
Cost for a Representative Facility
(Sulfur, Anhydrite)
Cost for a Representative Facility
(Sulfur, on-shore salt dome)
Cost for a Representative Facility
(Sulfur, off-shore salt dome)
Cost for a Representative Facility
(Mineral Pigments)
Cost for a Representative Facility
(Lithium Minerals)
Conversion Table
vii

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SECTION I
CONCLUSIONS
For purposes of establishing effluent limitations guidelines
and standards of performance, and for ease of presentation,
the mineral mining industry has been divided into three
segments to be published in three volumes: minerals for the
construction industry; minerals for the chemical and
fertilizer industries; and clay, ceramic, refractory and
miscellaneous minerals. These divisions reflect the end
uses of the minerals after mining and beneficiation. In
this volume covering minerals for the Chemical and
Fertilizer Industries, the 12 minerals are grouped into 12
production subcategories for reasons explained in
Section IV.
Based on the application of best practicable technology
currently available, 7 of the 12 production subcategories
under study can be operated with no discharge of process
generated waste water pollutants to navigable waters under
normal operating conditions. With the best available
technology economically achievable, 7 of the 12 production
subcategories can be operated with no discharge of process
generated waste water pollutants to navigable waters under
normal operating conditions. No discharge of process
generated waste water pollutants to navigable waters is
achievable as a new source performance standard for all
production subcategories except fluorspar (flotation),
phosphate rock (flotation), rock salt, sulfur (salt dome)
and lithium minerals. Mine water and contaminated plant
runoff are addressed separately.
This study includes 12 minerals for the chemical and
fertilizer industries of Standard Industrial Classification
(SIC) categories, 1472, 1473, 1474, 1475, 1476, 1477, 1479,
1499, and 3295 with significant waste discharge potential as
listed below with the corresponding SIC code.
1.
Barite (1472)
2.
Fluorspar (1473)
3.
Salines from Brine Lakes (1474)
4.
Borates (1474)
5.
Potash (1474)
6.
Trona Ore (1474)
7.
Phosphate Rock (1475)
8.
Rock Salt (1476)
9.
Sulfur (Frasch) (1477)
10.
Mineral Pigments (1479)
1

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11.	Lithium Minerals (1479)
12.	Sodium Sulfate (1474)
2

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SECTION II
RECOMMENDATIONS
The recommended effluent, limit.at.ions guidelines and the
suggested technologies are listed in Table 1. pH should be
maintained between 6.0 and 9.0 units at all times.
The pretreatment limitations will not limit total suspended
solids, unless there is a problem of sewer plugging, in
which case 40 CPR 128 131(c) applies. Limitations for
parameters other than TSS are recommended to be the same for
existing sources as best practicable control technology
currently available and new sources as new source
performance standards.
3

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Table 1
Recommended Limits and Standards for the Mineral Mining and Processing Industry
The follov7ing apply to process waste water except where noted
Subcategory
BPCTCA
max. avg. of 30
consecutive days
max, for
any one day
Barite
Dry
Wet & Flotation
Mine Drainage
(acid)
Mine Drainage
(non acid)
No discharge
No discharge
TSS 35 mg/1	TSS 70 mg/1
dis. Fe 0.3 mg/1 dis, Fe 0.6 mg/1
TSS 30 mg/1
F 0.4 kg/kkg
TSS 30 mg/1
Fluorspar
Heavy Media Separation
& Drying and Pelletizing	No discharge
Flotation	TSS 0.6 kg/kkg	TSS 1.2 kg/kkg
F 0.2 kg/kkg
Mine Drainage
Salines from Brine Lakes,**
Borax,
Potash,
Ti-ona (process "note water
and mine drainage), &
Sodium Sulfate
No discharge
Rock Salt (process waste water
and mine drainage)
Salt pile runoff
Phosphate Rock
Flotation unit process
and mine drainage
Other unit processes
Sulfur (Fraseh)
Anhydrite
Salt domes(land and
marsh operations
well bleed water)
Land available
Land availability
limitations
Well seal water
Mineral Pigments
Mine drainage
Lithium* ¦* (process
waste 'ater aud
mine drainage)
TSS 0.02 kg/kkg TSS 0.04 kg/kkg
TSS 30 mg/1	TSS 70 mg/1
Total Ra226 5 pci/l
No discharge
No discharge
TSS 50 mg/1*	T:S 100 mg/1*
S 1 mg/1	S 2 mg/1
S 5 mg/1	S 10 mp/1
No discharge of
elemental sulfur
No discharge
TSS 30 iag/1
TSS 0.11 kg/kkgi
F 0.017 kg/kkg
TSS 0.22 kg/kkg
V 0.034 kS/kkg
TSS 30 mg/1
BATEA and NSPS
max. avg. of 30 max. for
consecutive days any one day
No discharge
No discharge '
TSS 20 mg/1	TSS 40 rag/1
dis. Fe 0.3 mg/1 dis. Fe 0.6 mg/1
TSS 30 mg/1
Ho discharge
TSS 0.4 kg/kkg TSS 0.8 kg/kkg
F 0.1 kg/kkg
F 0.2 kg/kkg
TSS 30 mg/1
No discharge
TSS 0.002 kg/kkg TSS 0.004 kg/kkg
No discharge
TSS 30 mg/1	TSS 70 mg/1
Total Ra226 5 pci/l
No discharge
TSS 30 mg/1*
S 1 mg/1
S 1 mg/1
TSS 30 mg/1*
S 1 mg/1
TSS 60 mg/1*
S 2 mg/1
S 2 mg/1
TSS 60 mg/1*
S 2 mg/1
No discharge
iSS 30 mg/1
TSS 0.11 kg/kkg
F 0.008 kg/lckg
TSS 0.22 kg/kkg
F 0.016 kg/kkg
TSS 30 mg/1
pH 6~9 for ill subcategories
No discharge - No discharge of process waste water pollutants
kg/kkg - kg of pollutant/kkg of product
* staridatd is to apply as w.t if oxidation ditches are used and intake 1« from the snmo navigable
water as the discharge.
«*standards are to bo applied as net if discharge ia to the same navigable water a« brino intake
*** kg of poIlutant/J'kg of ore processed
BPCTCA - beat practicable control technology currently available
BATEA - beet available technology economically achievable
NSPS - new source performance standard
dis. - dissolved
4

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SECTION III
INTRODUCTION
PURPOSE AND AUTHORITY
The United States Environmental Protection Agency (EPA) is
charged under the Federal Water Pollution Control Act
Amendments of 1972 with establishing effluent limitations
which must be achieved by point sources of discharge into
the navigable water of the United states.
Section 301(b) of the Act requires the achievement by not
later than July 1, 1977, of effluent limitations for point
sources, other than publicly owned treatment works, which
are based on the application of the best practicable control
technology currently available as defined by the
Administrator pursuant to Section 304(b) of the Act.
Section 301(b) also requires the achievement by not later
than July 1, 1983, of effluent limitations for point
sources, other than publicly owned treatment works, which
are based on the application of the best available
technology economically achievable which will result in
reasonable further progress toward the national goal of
eliminating the discharge of all pollutants, as determined
in accordance with regulations issued by the Administrator
pursuant to section 304(b) to the Act. Section 306 of the
Act requires the achievement by new sources of a Federal
standard of performance providing for the control of the
discharge of pollutants which reflects the greatest degree
of effluent reduction which the Administrator determines to
be achievable through the application of the best available
demonstrated control technology, processes, operating
methods, or other alternatives, including, where
practicable, a standard permitting no discharge of
pollutants. Section 304 (b) of the Act requires the
Administrator to publish within one year of enactment of the
Act, regulations providing guidelines for effluent
limitations setting forth the degree of effluent reduction
attainable through the application of the best practicable
control technology currently available and the degree of
effluent reduction attainable through the application of the
best control measures and practices achievable including
treatment techniques, process and procedure innovations,
operation methods and other alternatives. The regulations
proposed herein set forth effluent limitations guidelines
pursuant to Section 304 (b) of the Act for the mining of
minerals for the chemical and fertilizer industries segment
of the mineral mining and processing point source category.
5

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Section 306 of the Act requires the Administrator, within
one year after a category of sources is included in a list
published pursuant to Section 306(b) (1) (A) of the Act, to
propose regulations establishing Federal standards of
performances for new sources within such categories. The
Administration published in the Federal Register of January
16, 1973 (38 F.R. 1624), a list of 27 source categories.
Publication of an amended list will constitute announcement
of the Administrators intention of establishing, under
Section 306, standards of performance applicable to new
sources within the mineral mining and processing industry.
The list will be amended when proposed regulations for
Mineral Mining and Processing are published in the Federal
Register.
SUMMARY OF METHODS
The effluent limitations guidelines and standards of per-
formance proposed herein were developed in a series of sys-
tematic tasks. The mineral mining and processing industry
was first studied to determine whether separate limitations
and standards are appropriate for different segments within
a point source category. Development of reasonable industry
categories and subcategories, and establishment of effluent
guidelines and treatment standards requires a sound
understanding and knowledge of the Mineral Mining and
Processing Industry, the processes involved, waste water
generation and characteristics, and capabilities of existing
control and treatment methods.
This report describes the results obtained from application
of the above approach to the mining of minerals for the
chemical and fertilizer industries segment of the mineral
mining and processing industry. Thus, the survey and
testing covered a wide range of processes, products, and
types of wastes.
The products covered in this report are listed below with
their SIC designations:
a.	Barite (1472 and 3295)
b.	Fluorspar (1473 and 3295)
c.	Salines from Brine Lakes (1974)
d.	Borax (1474)
e.	Potash (1474)
f.	Trona Ore (1474)
g.	Phosphate Rock (1475)
h.	Rock Salt (1476)
i.	Sulfur (1477)
j. Mineral Pigments (1479)
k. Lithium Minerals (1479)
1. Sodium Sulfate (1474)
6

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Categorization and Waste Load Characterization
The effluent limitation guidelines and standards of perform-
ance proposed herein were developed in the following manner.
The point source category was first categorized for the
purpose of determining whether separate limitations and
standards are appropriate for different segments within a
point source category. Such subcategorization was based
upon raw material used, product produced, manufacturing
process employed, and other factors. The raw wastes
characteristics for each subcategory were then identified.
This included an analysis of (1) the source and volume of
water used in the process employed and the sources of waste
and waste waters in the facility; and (2) the constituents
of all waste waters including harmful constituents and other
constituents which result in degradation of the receiving
water. The pollutants of waste waters which should be
subject to effluent limitations guidelines and standards of
performance were identified.
Treatment and Control Technologies
The full range of control and treatment technologies
existing within each subcategory was identified. This
included an identification of each control and treatment
technology, including both in-facility and end-of-process
technologies, which are existent or capable of being
designed for each subcategory. It also included an
identification of the amount of pollutants (including
thermal) and the characteristics of pollutants resulting
from the application of each of the treatment and control
technologies. The problems, limitations and reliability of
each treatment and control technology were also identified.
In addition, the non-water quality environmental impact,
such as the effects of the application of such technologies
upon other pollution problems, including air, solid waste,
noise and radiation were also identified. The energy
requirements of each of the control and treatment
technologies were identified as well as the cost of the
application of such technologies.
Data Base
Cost information contained in this report was obtained
directly from industry during facility visits, from
engineering firms and equipment suppliers, and from the
literature.
The data for identification and analyses were derived from a
number of sources. These sources included EPA research
information, published literature, qualified technical
consultation, on-site visits and interviews at numerous
7

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mining and processing facilities throughout the U.S.,
interviews and meetings with various trade associations, and
interviews and meetings with various regional offices of the
EPA. All references used in developing the guidelines for
effluent limitations and standards of performance for new
sources reported herein are included in Section XIII of this
report.
Table 2 summarizes the data base for the various sub-
categories studied in this volume.
Data was obtained from 82 percent of the facilities in this
segment of the mineral mining and processing industry.
Sixty four percent of the facilities were visited and
fifteen percent were sampled to verify data.
Facility Selection
The following selection criteria were developed and used for
the selection of facilities.
Discharge effluent quantities
Facilities with low effluent quantities or the ultimate of
no discharge of process waste water pollutants were
preferred. This minimal discharge may be due to reuse of
water, raw material recovery and recycling, or to use of
evaporation. The significant criterion was minimal waste
added to effluent streams per weight of product
manufactured. The amounts of wastes considered here were
those added to waters taken into the facility and then
discharged.
Land utilization
The efficiency of land use was considered.
Air pollution and solid waste control
The facilities must have possessed overall effective air and
solid waste pollution control where relevant in addition to
water pollution control technology. Care was taken to
insure that all facilities chosen have minimal discharges
into the environment and that these sites are not those
which are exchanging one form of pollution for another of
the same or greater magnitude.
Effluent treatment methods and their effectiveness
Facilities selected shall have in use the best currently
available treatment methods, operating controls, and
operational reliability. Treatment methods considered
8

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TABLE 2
DATA BASE
Subcategory
No. Plants
Visited
No. of Plants
Data
Available
Verification
Sampling
Barite
Dry-
Wet
Flotation
9
14
4
4
7
3
8
14
4
*
*
1
Fluorspar
HMS	6
Flotation	6
Drying and	2
Pelletizing
Salines from	3
Brine Lakes
Borax	1
Potash	5
Trona Ore	4
Phosphate Rock
Eastern	22
Western	6
4
4
1
1
4
2
21
6
6
5
2
1
5
4
20
6
*
2
*
*
*
*
5
2
Rock Salt
21
11
15
Sulfur
Anhydrite
On-Shore
Off-Shore
2
9
2
1
7
1
2
9
1
*
5
1
Mineral
Pigments
Lithium
Minerals
11
Soidum
Sulfate
Total
136
87
112
22
*There is no discharge of process waste water in the subcategories
under normal operating conditions.
9

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included basic process modifications which significantly
reduce effluent loads as well as conventional treatment
methods.
Facility facilities
All facilities chosen had all the facilities normally
associated with the production of the specific product(s) in
question. Typical facilities generally were facilities
which have all their normal process steps carried out
on-site.
Facility management philosophy
Facilities were preferred whose management insists upon
effective equipment maintenance and good housekeeping
practices. These qualities are best identified by a high
operational factor and facility cleanliness.
Geographic location
Factors which were considered include facilities operating
in close proximity to sensitive vegetation or in densely
populated areas. Other factors such as land availability,
rainfall, and differences in state and local standards were
also considered.
Raw materials
Differences in raw materials purities were given strong con-
sideration in cases where the amounts of wastes are strongly
influenced by the purity of raw materials used. Several
facilities using different grades of raw materials were
considered for those minerals for which raw material purity
is a determining factor in waste control.
Diversity of processes
On the basis that all of the above criteria are met,
consideration was given to installations having a
multiplicity of manufacturing processes. However, for
sampling purposes, the complex facilities chosen were those
for which the wastes could be clearly traced through the
various treatment steps.
Production
On the basis that other criteria are equal, consideration
was given to the degree of production rate scheduled on
water pollution sensitive equipment.
10

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Product purity
For cases in which purity requirements play a major role in
determining the amounts of wastes to be treated and the
degree of water recycling possible, different product grades
were considered for subcategorization.
GENERAL DESCRIPTION OF INDUSTRY BY PRODUCT
All underlined numbers appearing in a chemical formula
represent subscripts (e.g. H^O is water). The materials in
sic codes 1472 through 1477 and 1479 include a number of
different mineral compositions and have major use in the
chemical and fertilizer industries. Mining practices
include most all of the conventional surface and underground
methods. The extent of processing varies widely and the
complexity is dependent upon the particular mineral or
product being recovered. High water consumption is
associated with most of these production facilities with
wastes generated in the form of overburden, slimes, and
tailings.
The methods of mining and processing are generally common
for minerals such as barite, fluorspar, phosphate, and
lithium minerals. Open pit mining is more prevalent,
although some underground mines are in operation.
Processing may include combinations of crushing, grinding,
screening, washing, classification, flotation, magnetic
separation or filtering and drying. Waste treatment usually
includes flocculation and settling ponds with a high recycle
of process water.
A number of these mineral or chemical products are extracted
from brine lakes located in the western United States.
Materials such as borax, natural soda ash, lithium salts,
salt cake and potash are produced from the brines by a
series of processing steps involving evaporation and
selective precipitation. Production from other than the
brines occurs for the borates and potash. Deposits of these
materials are mined in open pits and/or underground and are
processed by various recovery methods such as flotation,
evaporation, precipitation, and crystallization.
The rock salt and trona deposits are of a very high purity
and are mined from underground operations. Processing of
the salt consists primarily of crushing and sizing while the
trona ore (impure sodium carbonate) is refined through a
series of impurity removal steps, evaporation and
crystallization.
11

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The major source of sulfur is salt domes with lesser
quantities coming from anhydrite deposits. The mining of
sulfur is accomplished by the Frasch or hot water process.
In the Frasch process, the sulfur is melted underground by
pumping hot water to the formations. The molten material is
removed to the surface and either stored or shipped in the
liquid form.
The 197 2 production and employment figures for the
industries mining and processing minerals for the chemical
and fertilizer industries were derived either from the
Bureau of the Census (U.S. Department of Commerce)
publications or the Commodity Data Summaries (1974) Appendix
I to Mining and Minerals Policy, Bureau of Mines, U.S.
Department of the Interior. These figures are tabulated in
Table 3.
BARITE (SIC 1472 & 3295)
Barite, which is also called barytes, tiff, cawk or heavy
spar, is almost pure barium sulfate and is the chief source
of barium and its compounds. Barite deposits are widely
distributed throughout the world, and can be classified into
three main types: (a) vein and cavity filling deposits; (b)
bedded deposits; and (c) residual deposits.
(a)	Vein and cavity-filling deposits are those in which the
barite and associated minerals occur along fault lines,
bedding planes, breccia zones and solution channels.
Barite deposits in the Mountain Pass district of
California are of this variety.
(b)	Bedded deposits are those in which the barite is
restricted to certain beds or a sequence of beds in
sedimentary rocks. The major commercial deposits in
Arkansas, Missouri, California and Nevada are bedded
deposits.
(c)	Residual deposits occur in unconsolidated material that
are formed by the weathering of pre-existing deposits.
Such deposits are abundant in Missouri, Tennessee,
Georgia, Virginia and Alabama where the barite is
commonly found in a residuum of limestone and dolomites.
Mining methods used in the barite industry vary with the
type and size of deposit and type of product made. Figure 1
displays the barite processing facilities in the United
States.
12

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SIC (
1472
1473
1474
1474
1474
1474
1475
1476
1477
1479
Table 3
Production & Employment
Product
Barite
Fluorspar
Borates
Potash (K2)
equlv.)
Sods Ash (Trona
only)
Sodium Sulfate
Phosphates
Salt (mined only)
Sulfur (Frasch)
Mineral Pigments
Lithium Minerals
1972 Production
kkg (tons)	
822,000
(906,000)
228,000
(251,000)
1,020,000
(1,120,000)
2,410,000
(2,660,000)
2,920,000
(3,220,000)
636,000
(701,000)
37,000,000
(40,800,000)
12,920,000
(14,200,000)
7,300,000
(8,040,000)
63,500
(70,000)
Withheld
Employment
1,025
270
1,800
1,200
1,070
100
4,200
2,800
2,900
Unknown
approx.
250
13

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FIGURE 1
RARITE PROCESSING PLANTS
The National Atlas of the USA
USGS - 1970

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Residual Barite in Clay
Residual barite in clay is dug with power shovels from open
pits (Missouri, Tennessee, Georgia). Stripping, when
overburden is heavy, is removed by dragline, tractors, and
scrapers or power shovel. Overburden in Missouri is rarely
over 2 or 3 feet, but in Georgia it may range from 10 to 50
feet. Hydraulic mining has been used at times in Georgia
where overburden has been heavy, where troublesome limestone
pinnacles have been encountered, or where tailing ponds have
been reclaimed.
Barite Veins or Beds
Barite veins or beds are mined underground (Nevada,
Tennessee, and Arkansas).
Massive Barite
Massive barite is blasted from open quarries with little or
no subsequent sorting or beneficiation (Nevada).
Methods used in the beneficiation of barite depend both on
the nature of the ore and on the type of product to be made.
For the largest use, well-drilling mud, the only
requirements are fine grind (325 mesh), chemical inactivity,
and high specific gravity. White color is not essential,
and purity is not important in many cases.
The essential features of the milling of residual barite in
clay (Missouri, Georgia, and Tennessee, in part) include
washing to remove the clay, hand picking to save lump
barite, jigging to separate coarse concentrates, and tabling
to recover fine concentrates. Further refinements may
include magnetic separation to remove iron from concentrate
fines and froth flotation to save the very finest barite.
In Missouri, where the ore is so soft that crushing is
unnecessary and individual deposits tend to be small, simple
and inexpensive facilities that can be easily dismantled and
moved are common. In Georgia, the ore is hard and usually
must be crushed to free the barite from the ganguej
facilities tend to be larger with several stages of
crushing, screening, jigging and tabling.
Missouri mills may consist essentially of only a double log
washer, trommel, and jigs, but there are a few larger mills.
Hard, vein barite is usually pure enough to be shipped
without beneficiation except by hand sorting.
The development of froth flotation methods for barite made
deposits, such as those of Arkansas and Georgia,
commercially valuable and greatly increased recovery
15

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possibilities from other deposits. The Arkansas ore is
particularly difficult to treat, since the barite is finely
divided and so intimately mixed with the impurities that
grinding to 325 mesh is necessary for complete liberation of
the component minerals. The ground ore is treated by froth
flotation. Concentrates are filtered and dried in rotary
kilns at temperatures high enough to destroy organic
reagents that might interfere with use in drilling muds. In
Georgia, flotation is being used to recover barite fines
from washer tailings.
Methods used in grinding barite depend upon the nature of
the product to be ground and upon the use for which the
ground barite is to be sold. If white color is not
important, as for well-drilling mud and off-color filler
uses, iron grinding surfaces may be used. Where the color
is naturally a good white and no bleaching is reguired,
grinding should be done with iron-free grinding surfaces,
such as a dry pebble mill in closed circuit with an air
separator.
The principal use of barite in the United States is as a
weighting agent for drilling muds used in the oil industry.
In addition, ground barite is used in the manufacture of
glass and as a heavy filler in a number of products where
additional weight is desirable.
FLUORSPAR (SIC 1473)
Fluorine is derived from the mineral fluorite, commonly
known as fluorspar. Steadily increasing quantities are
reguired in steel production where fluorite is useful as a
slag thinner; in aluminum production, where cryolite,
another fluorine mineral, is necessary to dissolve alumina
for the electrolytic cells; and in ceramics, where fluorite
is a flux and opacifier. Fluorine demand is strong for an
important group of fluorocarbon chemicals which are
formulated into refrigerants, plastics, solvents, aerosols,
and many other industrial products.
In the Illinois-Kentucky district the country rock is lime-
stone, shale, and sandstone. Fluorspar occurs as veins
along faults ranging in thickness from a mere film to a
width or more than 30 feet and in extensive flatlying
replacement-type deposits in limestone. Residual deposits,
resulting from weathering of fluorite-bearing veins, are
also fairly common in the district and often indicate the
presence of vein deposits at greater depth.
16

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In the Western States, fluorspar occurs under a wide variety
of conditions	as fillings in fractures and shear zones
forming more or less well-defined veins and as replacements
in the country rock. Much occurs in igneous formations.
Figure 2 depicts the locations of barite deposits in the
United States.
Mining is done by shafts, drifts, and open cuts with the
mines ranging in size from small operations using mostly
hand-operated equipment to large fully mechanized mines.
Mining methods follow the practice of metal mines, adopting
the method best suited to conditions. Top slicing, cut-and-
fill, shrinkage, and open stoping are among the methods
commonly used. Bedded deposits are usually worked by a
room-and-pillar system. Some of the large mines are
extensively mechanized, using diesel-powered hauling and
loading equipment.
The crude ore requires beneficiation to yield a finished
product. Processing techniques range from rather simple
methods, such as hand sorting, washing, screening and
gravity separation by jigs and tables, to sink-float and
froth-flotation processes. The flotation process permits
recovery of the lead, zinc, and barite minerals often
associated with the fluorspar ores.
Flotation is used where a product of fine particle size is
desired, such as ceramic- and acid-grade fluorspar. The
heavy-medium or sink-float process is usually employed where
a coarse product, such as metallurgical-grade gravel is
desired.
SALINES FROM BRINE LAKES (SIC 1474)
A number of the potash, soda and borate minerals of SIC 1474
are produced from the brines of lakes in the arid part of
the West that have evaporated over long periods of time to a
state of high concentration of minerals. The significant
commercial exploitation of these lake brines is at Searles
Lake in California and Great Salt Lake in Utah. Two
facilities are operated at Searles Lake that employ a
complex series of evaporation steps to recover minerals and,
in some instances, produce other derived products such as
bromine and boric acid. The process sequence is called the
••Trona Process", which should not be confused with trona ore
(natural sodium carbonate) mining that takes place in
Sweetwater County, Wyoming. One facility operates an
evaporative process at Great Salt Lake that produces sodium
sulfate, salt, potassium sulfate, and bittern liquors.
Figure 3 shows the potash deposits in the United States
including brine recovery. Figure 4 shows all of the borate
17

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CD
FIGURE 2
FLUORSPAR DEPOSITS
USGS-1970

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FIGURE 3
POTASI! DEPOSITS
*	-Mines
*-Wells
~	-Surface brines
t
o
3
From Salines chart-pg.181
The National Atlas.of The USA
USGS-1970

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FIGURE 4
BORATE OPERATIONS
USGS-1970

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deposits. Figure 5 shows the calcium and magnesium brine
locations.
BORATES (SIC 1474)
While boron is not an extremely rare element, few
commercially attractive deposits of boron minerals are
known. It is estimated that about half of the commercial
world boron reserves, estimated at about 72 million tons of
boron, are in southern California as bedded deposits of
borax (sodium borate) and colemanite (calcium borate), or
occur as solutions of boron minerals in Searles Lake brines.
Figure 4 shows the location of the United States operations.
The United States is the largest producer of boron, sup-
plying 71 percent of the world demand in 1968, and also the
largest consumer, requiring about 36 percent of the world
output.
Many minerals contain boron, but only a few are commercially
valuable as a source of boron. The principal boron minerals
are borax (tincal), Na2B407*10H2O; kernite (rasorite),
Na2B407*4H20; colemanite (borocalcite), Ca2B60V1*5H20;
ulexite (boronatrocalcite), CaNaB509*8H20; ~ priceite
(pandermite), 5Ca0*6B203*9H20; boracite (stassfurtite),
Mg7C12B16O30; and sassolite (natural boric acid), H3B03.
The sodium borate minerals borax and kernite (rasorite)
constitute the bulk of production in the United States. A
small quantity of colemanite and ulexite is also mined.
The borate deposit in the Kramer district of California is a
large, irregular mass of bedded crystalline sodium borates
ranging from 80 to about 1,000 feet in thickness. Borax,
locally called tincal, and kernite are the principal
minerals. Shale beds containing colemanite and ulexite lie
directly over and under the sodium borate body.
One company mines the ore by open-pit methods. It is
blended and crushed to produce a minus 3/4 inch feed of
nearly constant boric oxide (B203) content. weak borax
liquor from the refinery is mixed with the crushed ore and
heated nearly to boiling point in steam-jacketed tanks to
dissolve the borax. The concentrated borax liquor goes to a
series of thickeners, is filtered and pumped to vacuum
crystallizers. One of the crystallizers produces borax
pentahydrate, and the other produces borax decahydrate.
Sodium borates are also extracted from Searles Lake brines
by a company whose primary products are soda ash, salt cake,
and potash. Searles Lake is a dry lake covering about 34
square miles in San Bernardino County, California. Brines
pumped from beneath the crystallized surface of the lake are
21

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FIGURE 5
LITHIiri, CALCIUM ft TOESIin
	Lithium
» Calcium compounds(Brine)
x	Magnesium comp.(Brine)
From Salines Chart-pg.181
The National Atlas of The USA
USGS-1970

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processed by carbonation, evaporation, and crystallization
procedures, producing an array of products including boron
compounds.
Ferroboron is a boron iron alloy containing 0.2 to
24	percent boron. The alloys are marketed in various grain
sizes. Boric oxide is a hard, brittle, colorless solid
resembling glass. It is marketed in powder or granular
forms.
Borax (Na2B407*10H2O), the most commonly known boron
compound, is normally marketed with 99.5 percent purity. It
is also available in technical, U.S.P., and special-quality
grades. In addition to the decahydrate shown above, the
pentahydrate 
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In the conventional shaft-type mining operations, large con-
tinuous mining machines are used in both the New Mexico and
Canadian mines. Room-and-pillar mining methods are used in
New Mexico with a first-run extraction of about 65 percent
while in the deeper Canadian mines the first-run extraction
is in the order of 35 percent. On the second pass in the
New Mexico mines at least 55 percent of the remining potash
is recovered by "pillar robbing" for a total extraction of
about 83 percent of ore body. As much as 90 percent
recovery has been claimed for some operations. Pillar
robbing is not practiced in Canada and because of the
greater mine depth, it is not likely to be with present
technology.
Two basic methods of ore treatment, flotation and fractional
crystallization, are used both in the Carlsbad area and in
Canada to recover sylvite from the ore. In general, the
crushed ore is mixed with a brine saturated with both sodium
and potassium chlorides and deslimed to remove most of the
clay impurities. The pulp is conditioned with an amine
flotation reagent and sent to flotation cells where the
sylvite is separated from the halite, the principal
impurity. The halite fraction is repulped and pumped to
tailings; the sylvite concentrate is dried, sized, and
shipped or sent to storage.
Fractional crystallization is based on the specific
difference in the solubility-temperature relationships of
sodium chloride and potassium chloride in saturated
solution. Crushed ore is mixed with hot, saturated sodium
chloride brine, which selectively dissolves the potassium
chloride. The brine is then cooled causing the potassium
chloride to crystallize as a 99-percent-pure product.
Langbeinite, produced in the United States by IMC and Duval
Corp., is separated from halite, its principal impurity, by
the selective solution of the halite. The flotation process
is also used to separate langbeinite from sylvite.
Potassium compounds are recovered from brines, including
brines from solution mining, by evaporation and fractional
crystallization. The sodium salts in Searles Lake brines
are separated in triple-effect evaporators, leaving a hot
liquor rich in potash and borax. Rapid cooling of the
sodium-free solution under vacuum causes the potassium salts
to crystallize. The crystals of potassium salts are then
removed by settling and centrifuging.
About 84 percent of the domestic potash is produced in a
55-square mile area 15 miles east of Carlsbad, New Mexico.
The population density of the area is extremely low and the
semi-arid surface land is of little commercial value. There
24

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are eight refineries in this district, each requiring large
tailing disposal areas. Such operations in a heavily
populated area would present serious problems since the
tailings consist largely of sodium chloride salt;
consequently, areas covered with this waste are incapable of
supporting any facility life. The operation near Moab,
Utah, is similarly located, but extreme care must be
exercised to prevent pollution of the nearby Colorado River.
The brine operation in Utah requires large evaporating pans
covering many acres of the land surface. The area is
unpopulated so the large land area needed for concentrating
the brine by solar evaporation presents no problem. The
process involved here involves evaporation of Great Salt
Lake waters first to recover common salt (NaCl) and then, by
evaporation, to recover potassium sulfate. From the
selective evaporation process, all residual brines,
containing mostly magnesium and lithium salts are returned
to the lake.
TRONA (SIC 1474)
Trona (Na2C03NaHC03* 2H20) is the most common sodium
carbonate mineral found in nature. It crystallizes when
carbon dioxide gas is bubbled through solutions of sodium
carbonate having a concentration greater than 9 percent.
Carbonation of less concentrated solutions precipitates
sodium bicarbonate. The largest known deposit of relatively
pure trona in the United states was discovered in southwest
Wyoming in 1938 while drilling for oil near Green River.
The deposit is relatively free of chlorides and sulfates and
contains 5 to 10 percent insoluble matter and constitutes
the only mineable quantity of this material. It is also the
worlds largest natural source of sodium carbonate
(soda ash).
Trona is a sedimentary deposit precipitated in the bottom of
the ancient Eocene Lake Gosiute. Subsequent deposits of oil
shale, siltstone and sandstone covered the trona and the
beds that are mined are at 800 to 1500 feet below the
surface. Approximately 25 different trona-bearing beds lie
buried at depths of 140 to 3500 feet.
Trona ore mining is carried out near Green River, Wyoming by
four corporations. Only three have soda ash refining
facilities on site at the present time. The increasing
industrial use of soda ash, together with the phasing out of
obsolete and controversial synthetic soda ash facilities in
the East has caused a great spurt of growth in the trona ore
industry from the early 1960*8. The mineable resources of
trona in this area have been estimated to be 45 billion kkg
(50 billion short tons).
25

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SODIUM SULFATE
Natural sodium sulfate is derived from the brines of Searles
Lake in California, certain underground brines in Texas, and
dry lake brines in Wyoming. Sodium sulfate is also derived
as a by-product from rayon production, which requires that
caustic solutions used in processing cellulose fiber be
neutralized with sulfuric acid, other sources of by-product
sodium sulfate include the chemical processes that produce
hydrochloric acid, cellophane, boric acid, lithium
carbonate, phenol, and formic acid.
The natural sodium sulfate is produced by six facilities in
California, Utah, and Texas. Three facilities in California
produce 74 percent of the natural product.
ROCK SALT (SIC 1476)
Sodium chloride, or salt, is the chief source of all forms
of sodium. Salt is produced on a large scale from bedded
and dome-type underground deposits and by evaporating lake
and sea brines. Increasing, quantities of two commercially
important sodium compounds, sodium carbonate (soda ash) and
sodium sulfate (salt cake), are produced from natural
deposits of these compounds, although salt is still the main
source of both.
Bedded salt deposits are formed when a body of sea water
becomes isolated from the circulating ocean currents by a
reef, sandbar, or other means, and under suitably dry and
warm climatic conditions the evaporation proceeds until the
salts are partially or entirely deposited. With continuous
or periodic influx of sea water to replace evaporation,
large deposits of salt have been built up (in some instances
to several thousand feet in thickness). Deposits of this
type have also been called lagoonal. During the Permian
geologic age two famous salt deposits of the lagoonal type
were laid down, one in northern Germany and the other in
eastern New Mexico. A second large bedded deposit in the
United States is the Silurian salt deposit, which underlies
Michigan, New York, Pennsylvania, Ohio, and West Virginia.
It was formed in much the same manner as the Permian beds by
the evaporation of a large inland sea which became separated
from the ocean and gradually evaporated.
Playa deposits are formed by leaching of surrounding
sediments with water, which subsequently drains into a
landlocked area and evaporates, leaving the salts. The
composition of the brines and salt beds of these deposits
generally does not resemble that of sea water; playa
deposits of California and Nevada contain, in addition to
26

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sodium chloride, sodium carbonate, sodium sulfate, potash
and boron.
Salt domes are large vertical structures of salt, resulting
from deformation of deeply buried salt beds under great
pressure. The plastic nature of halite under high
temperature and pressure and its low density, compared with
that of the surrounding rock, permits deeply buried
sedimentary deposits to be forced upward through zones of
weakness in the overlying rocks, forming vertical columns or
domes of salt extending several thousand feet in height and
cross section. If the bedded deposit at the base of the
dome is sufficiently large, the salt columns may rise to the
surface. There are reportedly 300 salt domes in the gulf
coast area from Alabama to Mexico.
Rock salt is mined on a large scale in Michigan, Texas, New
York, Louisiana, Ohio, Utah, New Mexico, and Kansas, with
room-and-pillar the principal mining method. Rooms vary in
size depending on the thickness of the seam and other
factbrs. Salt mining is similar to coal mining and is
highly mechanized. In one mine an undercutter cuts a slot
10 feet deep at the base of the wall, which is then drilled
and blasted. About 0.2 kg of dynamite per kkg of salt is
required. The broken salt is transported by various
mechanical means such as loaders, trucks, and belt conveyors
to the underground crushing area. The salt may be processed
through a number of crushing and screening stages prior to
being hoisted to the surface where the final sizing and
preparation for shipment or further use is carried out.
About 57 percent of the U.S. salt output is produced by
introducing water into a cavity in the salt deposits and
removing the brine. This procedure is relatively simple and
has particular advantage when the salt is to be used as a
brine as, for example, in chemical uses such as soda ash and
caustic manufacture. Holes are drilled through the
overburden into the deposit and cased with iron pipe. Water
is introduced into the deposit through a smaller pipe inside
the casing. A nearly saturated brine is formed in the
cavity at the foot of the pipe. This brine is pumped or
airlifted through the annular space between the pipes.
Figure 6 shows the locations of current rock salt operations
in the United States.
PHOSPHATE ROCK (SIC 1475)
"Phosphate rock" is a commercial term for a rock containing
one or more of the phosphate minerals, usually calcium phos-
phate, of sufficient grade and suitable composition to per-
mit its use, either directly or after concentration, in
manufacturing commercial products. Hie term "phosphate
27

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FIGURE 6
ROCK SALT nif€S * WELLS
USGS-l970

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rock." includes phosphatized limestones, sands-tones, shales,
and igneous rocks which do not have a definite chemical
composition. The major phosphorus minerals of most
phosphate rock are in the apatite group and can be
represented by the generalized formula Ca5(P04)3 - (F, Cl,
OH). The (F, Cl, OH) radical may be all fluorine, chlorine,
or hydroxyl ions or any combination thereof. The (P04)
radical can be partly replaced by small quantities of V04,
As04, Si04, SO4, and C03. Also, small quantities of calcium
may be replaced by many elements such as magnesium,
manganese, strontium, lead, sodium, uranium, cerium, and
yttrium. The major impurities include iron as limonite,
clay, aluminum, fluorine, and silica as quartz sand.
Phosphate rock occurs as nodular phosphates, residual
weathered phosphatic limestones, vein phosphates, and conso-
lidated and unconsolidated phosphatic sediments. The best
known of the apatite minerals, fluorapatite is widely
distributed. Relatively small deposits of fluorapatite
occur in many parts of the world. The domestic deposits
that are currently being exploited are indicated in Figure
7.
Phosphate ore is mined by open pit methods in all four pro-
ducing areas: Florida, North Carolina, Tennessee, and the
Western States. In the Florida land-pebble deposits, the
overburden is stripped and the ore mined by large electric
dragline excavators equipped with buckets, with capacities
up to 49 cubic yards. The ore is slurried and pumped to the
washing facility, in some instances several miles from the
mine. In the Tennessee field and the open pit mines in the
western field, the ore is mined by smaller dragline
excavators, scrapers or shovels and trucked to the
facilities. In North Carolina a 72-cubic-yard dragline is
used for stripping, and the ore is then hydraulically
transported to the washer.
All of the North Carolina and nearly all Florida and
Tennessee phosphate ore must be treated before utilization.
Washing is accomplished by sizing screens, log washers,
various types of classifiers, and mills to disintegrate the
large clay balls. The fine slime, usually minus 150 mesh,
is discarded. in the Florida land-pebble field, the plus
14 mesh material is dried amd marketed as high-grade rock or
sometimes blended with the fine granular material (minus 14,
plus 150 mesh) that has been treated in flotation cells,
spirals, cones or tables. Losses in washing and flotation
operations, which range from 40 percent of the phosphorus in
the Florida operations to more than 50 percent in some
Tennessee areas, occur in the form of slimes containing 4 to
6 percent solids. These slimes are discharged into settling
ponds, where initial settling occurs, and substantial
29

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FIGURE 7
PHOSPHATE mniffi 8 PROCESSING LOCATIONS
flinerals chart-pg.184.
The National Atlas of The USA
USGS-1970

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quantities of relatively clear water is returned to the
mining and washing operations.
Some of the western field phosphate rock production is of
suitable grade as it comes from the mine. Siliceous
phosphate ore and mixtures of phosphate rock and clay
minerals are amenable to benefication, and in 1968 three
companies in the western field were beneficiating part of
their production. Two flotation facilities and several
washing facilities were in operation in 1968.
Several environmental problems are associated with the
phosphorus and phosphate industry. In the southeastern
states mining and processing of phosphate rock is located
close to developed and expanding urban areas. In the
Florida land-pebble district the phosphate matrix (ore)
underlies 1.2 to 18 meters (4 to 60 feet) of overburden
consisting mostly of sand and clay requiring the use of
large draglines to remove the overburden. The major mining
companies, together and individually, have embarked upon a
continuing program of reclamation of mined-out areas and are
planning mining operations to provide easier and more
economical methods of reclamation. Many thousands of acres
of land have been reclaimed since the program started.
The Florida phosphate rock washing operations, because of
the nature of the material, produces large quantities of a
slurry of very fine clay and phosphate minerals called
slimes. This is a waste product and must be contained in
slime ponds that cover large areas since many years of
settling are required before these pond areas can be
reclaimed. Much research effort has been expended by both
government and industry to solve this problem which is not
only an environmental one but also one of conservation since
about 33 percent of the phosphorus values are wasted. some
progress has been made and old slime ponds are now being
reclaimed for recreational, agricultural, and other uses.
The greatest problems of this nature exist in central
Florida but similar situations prevail in northern Florida
and Tennessee.
SULFUR (SIC 1477)
Elemental sulfur is found in many localities generally in
solfataras and gypsum-type deposits. By far, most of the
world's supply of sulfur comes from the gypsum-type deposits
where it occurs as either crystalline or amorphous sulfur in
sedimentary rocks in close association with gypsum and
limestone. The origin of such deposits has been variously
attributed to geochemical processes involving the reduction
of calcium sulfate by carbon or methane followed by
oxygenation of the resulting hydrogen sulfide; or to
31

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biochemical processes involving -the reduction of sulfate to
sulfide by various microorganisms.
The major domestic sources of sulfur are associated with the
Gulf Coast salt domes which characteristically are circular
or oval in cross-section with the sulfur-bearing cap rock
occurring at depths of less than 900 meters (3000 feet).
The diameter of the domes may vary from 0.8 to 8 km (one-
half to five miles) with a dry, compact, coarsely
crystalline salt column below the cap rock. Most of the
elemental sulfur is found in the limestone or carbonate zone
of the cap rock with a horizon which may vary from nearly
zero to several hundred meters in thickness having sulfur
content which may range from traces to more than 40 percent.
The sulfur formations in West Texas are in porous zones of
gently dipping dolomitic limestone, silty shale, anhydride
and gypsum. The sulfur deposits are low grade and the
layers that contain sulfur are thin. Depths of the sulfur
deposits range from 200 to 460 m (700 to 1,500 feet).
Surface exposures of sulfur in porous gypsum and anhydrite
are distributed over a rectangular area about 64 km long and
48 km wide (40 miles long and 30 miles wide) in both
Culberson and Reeves counties.
Mining of sulfur is accomplished by the Frasch or hot water
process. In the Frasch process, the sulfur is melted
underground by pumping hot water to the formation. The
molten sulfur is then raised to the surface through the
drill pipe and stored in liquid form in steam-heated tanks.
In most installations, the liquid sulfur is pumped directly
into heated and insulated ships or barges that can transport
the sulfur in liquid form. Approximately 15 percent of the
total sulfur produced in the U.S. is metered and pumped to
storage vats for cooling and solidifying before it is sold
in dry form.
Sulfur has widespread use in the manufacturing of
fertilizers, paper, rubber, petroleum products, chemicals,
plastics, steel, paints and other commodities, with the
fertilizer industry consuming approximately 50 percent of
the total U.S. sulfur production. The locations of the
United states sulfur deposits is shown in Figure 8.
MINERAL PIGMENTS
The mineral pigments consist of three general groups:
(1)	Those consisting mostly of iron oxides such as hematite
and limonite.
(2)	Those containing large amounts of clay or noncoloring
matter, such as ocher, sienna, umber and colored shales.
32

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FIGURE 8
SULFUR DEPOSITS
From Industrial and Chemical Minerals chart-
pg.184
The National Atlas of The USA
USGS-1970

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(3) Those whose color is not due to iron oxide such as
Vandyke brown, graphite and terre-verte.
Since the coloring power of the natural yellow, red, and
brown mineral pigments is due principally to the content and
condition of iron oxide, the occurrence of mineral pigments
in many instances is closely allied to that of the iron
ores. Pigment materials and iron ores often are mined in
the same localities, and iron ores are used at times for
mineral pigments of the red and brown varieties. The iron
oxides are almost universally distributed.
Replacement or precipitation deposits are the principal
sources of limonite and ocherous minerals. They have been
deposited in cavities by ground waters charged with iron
salts removed from the weathering of impure limestone,
sandstones, and shales, especially when pyrite was an
accessory mineral. The most important deposits are found
usually in the fractured and faulted zones of rocks of all
ages, including the Cambrian quartzites of Georgia, the
Paleozoic limestones and quartzites of Pennsylvania, and the
unconsolidated Tertiary clays, sands, manganese ores, and
lignites of Vermont.
In Virginia, deposits of residual limonite occur in two
belts, one extending along the west slope of the Blue Ridge
from Warren to Roanoke County and the other along the east
side of the New River-Cripple creek district, Pulaski
County, and near the boundary of Wythe and Carroll counties.
The latter deposits are associated with Cambrian quartzites.
The deposits in Pulaski County have produced ochers of high
iron content somewhat similar in analyses and properties to
the Georgia ocher.
The chief production of earth pigments in the United States
in recent years has come from Pennsylvania, Virginia,
Illinois, Minnesota, Georgia, California, and New York.
In Pennsylvania, ocher is mined both by opencut methods and
shafts, and in Georgia by opencut methods. In most deposits
the pockety character of the ore and the uncertain market
for the product do not justify elaborate equipment.
The soft, claylike pigments are treated by comparatively
simple washing processes, followed by dehydration and
pulverization. Log washers and blungers are used for
dispersion; trough, cone, and bowl classifiers separate the
sand from the fine suspension. A portion of -the water is
removed in settling tanks and the remainder is extracted by
filter presses and rotary driers. Hammer type pulverizers
reduce the pigment to powder for packing and shipment and a
34

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final air separation may be interposed for -the better
grades.
LITHIUM MINERALS (SIC 1479)
Spodumene, petalite, lepidolite, and amblygonite are the
minerals from which lithium is derived. Brines are another
source of lithium. Domestic spodumene is recovered by
mechanical mining and milling processes, and either an acid
or an alkali method is used to extract lithium compounds
from the spodumene ore.
Lithium minerals have been mined from pegmatite depostis by
open pit and underground methods. Other minerals such as
beryl, columbite, feldspar, mica, pollucite, quartz, and
tantalite are often extracted and recovered as coproducts in
the mining process.
In North Carolina spodumene is recovered from the pegmatite
ore by crushing, screening, grinding, and flotation, and
lithium compounds are recovered from spodumene concentrates
by an acid or an alkali treatment. In the method employing
acid, spodumene is changed from the alpha form to the beta
form by calcining at 982°C (1,800°F). Next it is added to
sulfuric acid and the mixture is heated until lithium
sulfate is formed. The sulfate is then leached from the
mass, neutralized with limestone, and filtered. Soda ash is
added to the sulfate solution in order to precipitate
lithium carbonate from which most of the other compound
forms are prepared. In the alkali treatment, spodumene is
stage-calcined with powdered limestone and hydrolyzed with
steam to produce a water-soluble lithium oxide. This can be
easily recovered and converted to the desired lithium com-
pound .
Certain natural brines are also a source of lithium. At
Searles Lake, California, brine (0.033 percent lithium
chloride) is first concentrated in evaporators causing
several salts to precipitate, including dilithium sodium
phosphate, sodium chloride, and a mixture of other sodium
salts. Through a combined leach-flotation process the
lithium compound is recovered as crystals and then fed to a
chemical facility to be converted to lithium carbonate. The
brines at Silver Peak, Nevada (0.244 percent LiCl) are con-
centrated to a LiCl content of 6 percent by solar
evaporation. This concentrate is then pumped to a nearby
mill where a soda ash process changes the chloride to solid
lithium carbonate. Lithium metal is produced by the
electrolysis of lithium chloride. Figure 5 shows the
domestic lithium deposits.
35

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SECTION IV
INDUSTRY CATEGORIZATION
INTRODUCTION
In the development of effluent limitations guidelines and
recommended standards of performance for new sources in a
particular industry, consideration should be given to
whether the industry can be treated as a whole in the
establishment of uniform and equitable guidelines for the
entire industry or whether there are sufficient differences
within the industry to justify its division into categories.
For this segment of the mineral mining and processing
industry, which includes twelve mineral types, the following
factors were considered as possible justifications for
industry categorization and subcategorization:
(1)	manufacturing processes;
(2)	raw materials;
(3)	pollutants in effluent waste waters;
(4)	product purity;
(5)	water use volume;
(6)	facility size;
(7)	facility age; and
(8)	facility location.
INDUSTRY CATEGORIZATION
The first categorization step was to segment the mineral
mining and processing industry according to product use.
Thus, Volume I is "Mining of Minerals for the Construction
Industry," this volume. Volume II, is "Mining of Minerals
for the Chemical and Fertilizer Industries," and Volume III
is "Mining of Clay, ceramic. Refractory and Miscellaneous
Minerals."
The reason for this division is twofold. First the
industries in each volume generally have the same waste
water treatment problems. Secondly, this division results
in development documents that are not so big that the reader
37

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may easily forget earlier points as he reads from section to
section.
The first cut in subcategorization was made on a commodity
basis. This was necessary because of the large number of
commodities and in order to avoid insufficient study of any
one area. Furthermore, the economics of each commodity
differs and an individual assessment is necessary to insure
that the economic impact is not a limiting factor in
establishing effluent treatment technologies. Table 4 lists
the 18 subcategories in this report.
FACTORS CONSIDERED
Manufacturing Processes
Each commodity can be further divided into three very
general classes - dry crushing and grinding, wet crushing
and grinding (shaping), and crushing and beneficiation
(including flotation, heavy media, et al) where such
differences exist. Each of these processes is described in
detail in Section V of this report, including process flow
diagrams pertinent to the specific facilities using the
process.
Raw Materials
The raw materials used are principally ores, which vary
across this segment of the industry and also vary within a
given deposit. Despite these variations, differences in ore
grades do not generally affect the ability to achieve the
effluent limitations. In cases where it does, different
processes are used, as is the case for fluorspar, and
subcategorization is better applied by process type as
described in the preceding paragraph.
Product Purity
The mineral extraction processes covered in this report
yield products which vary in purity from what would be
considered a chemical technical grade to an essentially
analytical reagent quality. Pure product manufacture
usually generates more waste than the production of lower
grades of material, and thus could be a basis for
subcategorization. As is the case for variation of ore
grade discussed under raw materials, pure products usually
result from different beneficiation processes, and
subcategorization is applied more advantageously there.
38

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TABLE 4
Industry Categorization
Commodity	SIC Code
Barite	1472 and
3295
Fluorspar	1473 and
3295
Salines from	various
Brine Lakes
Borax	1474
Potash	1474
Trona	1474
Sodium Sulfate	1474
Rock Salt	1476
Phosphate Rock	1475
Sulfur (Frasch)	1477
Mineral Pigments	1479
Lithium Minerals	1479
Subcategory
Dry
Wet
Flotation
Heavy Media Separation
Flotation
Drying and Pelletizing
No
further
subcategorization
No
further
subcategorization
No
further
subcategorization
No
further
subcategorization
No
further
subcategorization
No
further
subcategorization
Flotation units
Non-flotation units
Anhydrite
On-shore
No further subcategorization
No further subcategorization
39

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Facility Size
For -this segment of -the industry, information was obtained
from more than 95 different mineral mining sites. Capacity
varied from as little as one kkg/day to 12,500 kkg/day. The
variance of this factor was so great that facility size was
not felt to be useful in categorizing this segment of the
industry. Furthermore, setting standards based on kg
pollutant/kkg production minimizes the differences in
facility sizes. The economic impact on plant size will be
addressed in another study.
Facility Age
The newest facility studied was less than a year old and the
oldest was 88 years old. There is no correlation between
facility age and the ability to treat process waste water to
acceptable levels of pollutants. Also, the equipment in the
oldest facilities either operates on the same principle or
is identical to equipment used in modern facilities.
Therefore, facility age was not an acceptable criterion for
categorization.
Facility Location
The locations of the more than 95 mineral mining and
processing sites studied are in nineteen states spread from
coast to coast and north to south. Some facilities are
located in arid regions of the country, allowing the use of
evaporation ponds and surface disposal on the facility site.
Other facilities are located near raw material mineral
deposits which are highly localized in certain areas of the
country. In these instances, geographical location was felt
to be a legitimate criterion for industry subcategorization.
Thus, facility location was used for further segmentation
within a category, but not for categorization.
40

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SECTION V
WATER USE AND WASTE CHARACTERIZATION
INTRODUCTION
This section discusses the specific water uses in the
minerals for the chemical and fertilizer industries segment
of the mineral mining and processing industry, and the
amounts of process waste materials contained in these
waters. The process wastes are characterized as raw waste
loads emanating from specific processes in the extraction of
the materials involved in this study and are generally given
either in terms of kg/kkg of product produced or ore
processed lb/1000 lb). The specific water uses and amounts
are generally given in terms of 1/kkg of product produced or
ore mined (gal/ton) for each of the facilities contacted in
this study. Where appropriate, the water uses and raw waste
loads are given in either 1/day (gal/day) or concentration,
mg/1, respectively. The treatments used by the mining and
processing facilities studied are specifically described and
the amount and type of waterborne waste effluent after
treatment is characterized.
The verification sampling data measured at specific
facilities for each subcategory is included in this report
where industry data and data from other sources is lacking.
SPECIFIC WATER USES
Waste water originates in the mineral mining and processing
industry from the following sources:
(1)	Non-contact cooling water
(2)	Process generated waste water - wash water
transport water
scrubber water
process and product consumed water
miscellaneous water
(3)	Auxiliary processes water
(4)	Storm and ground water - mine water
storm water
Non-contact cooling water is defined as that cooling water
which does not come into direct contact with any raw
material, intermediate product, by-product or product used
in or resulting from the process. Such water will be
regulated by general limitations applicable to all
industries.
41

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Process generated waste water is defined as that water
which, in the mineral processing operations such as
crushing, washing and beneficiation, comes into direct
contact with any raw material, intermediate product,
by-product or product used in or resulting from the process.
Auxiliary processes water is defined as that used for
processes necessary for the manufacture of a product but not
contacting the process materials, for example influent water
treatment. Such water will be regulated by general
limitations applicable to all industries.
The quantity of water usage for facilities in the minerals
for the chemical and fertilizer industries segment of the
mineral mining and processing industry ranges from 0 to
726,400,000 1/day (0 to 191,900,000 gal/day). In general,
the facilities using very large quantities of water use it
for heavy media separation and flotation processes in some
cases, wet scrubbing and non-contact cooling, and
specifically, in sulfur mining, as the process medium.
Non-Contact Cooling Water
The largest use of non-contact cooling water in this segment
of the mineral mining industry is for the cooling of
equipment, such as kilns, pumps and air compressors.
Contact Cooling water
Insignificant quantities of contact cooling water are used
in this segment of the mineral mining industry. When used,
it usually either evaporates immediately or remains with the
product.
Wash Water
This water also comes under the heading of process water
because it comes into direct contact with either the raw
material, reactants or products. Examples of this type of
water usage are ore washing to remove fines and filter cake
washing. Waste effluents can arise from these washing
sources, due to the fact that the resultant solution or
suspension may contain impurities or may be too dilute a
solution to reuse or recover.
Transport water
Water is widely used in the mineral mining industry to
transport ore to and between various process steps. Water
is used to move crude ore from mine to facility, from
crushers to grinding mills and to transport tailings to
final retention ponds. Transport water is process water.
42

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Scrubber Water
Particularly in the dry processing of many of the minerals
in this industry, wet scrubbers are used for air pollution
control. These scrubbers are primarily used on dryers,
grinding mills, screens, conveyors and packaging equipment.
Scrubber water is process water.
Process and Product Consumed Water
Process water is primarily used in this industry during
blunging, pug milling, wet screening, log washing, sulfur
extraction, heavy media separation and flotation unit
processes. The largest volume of water is used in the
latter three processes. Product consumed water is often
evaporated or shipped with the product as a slurry or wet
filter cake.
Miscellaneous Water
These water uses vary widely among the facilities with
general usage for floor washing and cleanup, safety showers
and eye wash stations and sanitary uses. The resultant
streams are either not contaminated or only slightly
contaminated with wastes. The general practice is to
discharge such streams without treatment or combine with
process water prior to treatment.
Another miscellaneous water use in this industry involves
the use of sprays to control dust at crushers, conveyor
transfer points, discharge chutes and stockpiles. This
water is usually low volume and is either evaporated or
absorbed in the ore. The water uses so described are
process waters.
Auxiliary Processes Water
Auxiliary processes water include blowdowns from cooling
towers, boilers and water treatment. The volume of water
used for these purposes in this industry is minimal.
However, when they are present, they usually are highly
concentrated in waste materials.
Storm and Ground Water
Water will enter the mine area from three natural sources,
direct precipitation, storm runoff and ground water
intrusion. Water contacting the exposed ore or disturbed
overburden will be contaminated. Storm water and runoff can
also become contaminated at the processing site from storage
piles, process equipment and dusts that are emitted during
processing.
43

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PROCESS WASTE CHARACTERIZATION
The mineral products are generally discussed in SIC Code
numerical sequence in this section. For each mineral
product the following information is given:
—	a short description of the processes at the
facilities studied and pertinent flow diagrams;
—	raw waste load data per unit weight of product
or raw material processed;
—	water consumption data per unit weight of product
or raw material processed;
—	specific facility waste effluents found and the post-
process treatments used to produce them.
BARITE (SIC 1472)
There are twenty-seven significant U.S. facilities producing
either barite ore or ground barite. Nine of these
facilities are dry grinding operations, producing different
grades of ground barite, fourteen use log washing and
jigging methods to prepare the ore for grinding and four are
wet flotation facilities using froth flotation techniques
for the beneficiation of the washed and/or jigged ore.
BARITE (DRY PROCESS)
Process Description
Methods used in grinding barite depends upon the nature and
condition of the product to be ground and upon the
application for which the product is to be sold. In a dry
grinding mill, the ore from facility stockpiles is batched
in ore bins. In most facilities the ore is soft and
crushing is not necessary prior to the milling operation.
In these facilities, the ore is fed via a conveyor belt to
the mill for processing. In some other facilities, the ore
is hard and must be crushed before grinding to free barite
from the gangue material. After milling, the ground product
passes through a cyclone and vibrating screen before being
pumped into the product silos. The product is reclaimed
from these silos, and either pumped to bulk hopper cars or
to the bagging facility. A generalized flow diagram for dry
processing of barite is given in Figure 9.
44

-------
ORE
in
FIGURE 9.
8ARI7E and processing
I n
V ^
.'A T v?i~\'«Vu^5i t ^ J ;%W4':U-*~ Z3 /

-------
Raw Waste Loads
The only waste is dust from baghouse collectors which is
handled as a dry solid.
Water Use
No water is used in dry grinding facilities. There is no
pumping of mine water in this subcategory.
Waste Water Treatment
None required.
Effluent
None.
BARITE - WET PROCESS (LOG WASHING AND JIGGING OPERATIONS)
Process Description
The wet processing facilities use washers or jigs to remove
the clay from the barite ore. The mined ore is soft and is
passed through a breaker and then fed to the washing
circuit. Washing the barite laden earth is accomplished in
the log washer. The washed ore is next screened in a
trommel circuit, dewatered and then jigged to separate
gravel from the barite product.
In facility 2013, the ore is first processed in a trommel
screen to separate the fines (-3/4'1 material). The +1 1/2"
material is then crushed and the resulting -tt" barite
product is sent to the stockpile. The +3/4 to 1 1/2H
material is processed in a jig facility to separate gravel
from the barite product. A generalized flow diagram for wet
processing is given in Figure 10.
In all these facilities, barite is mined in dry open pits.
In most facilities, the clay strata is excavated by power
shovel or dragline and hauled to the washing facility by
dump trucks. In facility 2013, the barite and the waste
(chert) is separated in the pit by a dozer, the ore is then
dried in place, and the fines are separated by means of a
trommel. Several caterpillar dozers with rippers are used
for ripping, then pushing the ore into piles to be loaded
and hauled to the crusher at the processing facility.
The quantity of the clay, sand and gravel, and rock in the
ores mined in these facilities varies from location to
location. The pure barite amounts to 3-7 percent by weight
46

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SOLID WASTE
MAKE-UP WATER AND RECYCLED WATER
FROM THE TAILINGS POND
I
1
f
1




i
f'l
w
BREAKER

LOG
WASHER
		 Cr»
TROMMEL
SCREEN

DEWA7ER

JIGS
WASTE
TO
SETTLING POND
t
SOLID WASTE
r
WASTE
TO
SETTLING POND
?
WATER
TO
SETTLING POND
FIGURE m
BARITE MINING AND PROCESSING
(WET PROCESS)

-------
of the material mined for most facilities. Some waste
material is removed at the mine site without use of water.
Raw Waste Loads
The process raw wastes in this subcategory consist of the
mill tailings from the washing and jigging circuits. The
range of the raw wastes is given as follows:
Waste	kg/kkg of feed
Clays and sands	230 - 970
Water Use
The quantity of the water used in these facilities depends
upon the quality of the ore and the type of the waste
material associated with the ore as given as follows:
water consumption in 1/kka
of product (gal/ton)

barite recovery


sanitary and
Facility
from . feed	(%)
process
water
misc. usage
2011
63
62,600
(15,000)
650 (150)
2012
63
140,200
(33,600)
	
2013
77
7,200
(1,725)
	
2015
5.7
162,700
(39,000)

2016
4.8
239,400
(57,400)

2017
3.3
291,300
(69,800)
12,380 (3,270)
2018
3.9
246,500
(59, 100)
8,382 (2,215)
2020
54
62,600
(15,000)
650 (150)
2046
63
140,200
(33,600)
— — —
The exceptional facility in the
above table is 2013. This
facility uses water at an average of only 7r200 1/kkg
product (1,725 gal/ton) because only 30-10 percent of the
ore goes through jigging. The majority of the barite at
this facility is dry ground.
In facilities 2012, 2013 and 2046, the process water volumes
given include the water used for sanitary purposes. In all
facilities, the process water is recycled. Makeup water may
be required in some of these facilities.
Waste Water Treatment
The waste water streams are combined and sent to settling
ponds and the reclaimed water from the ponds is recycled to
the washing facilities. At facilities 2012 and 2046, the
overflow from the settling pond percolates through gravel
piles amassed around the settling pond, and enters
48

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clarif ica-tion ponds. The supernatant water from the
clarification pond is then recycled to the facilities for
reuse. Also, in these facilities (2012 and 2046), there are
several small ponds created around the main impoundment area
to catch any accidental overflow from the clarification
ponds. Besides ponding, facilities 2015 and 2016 also use
coagulation and flocculation to treat their process waste
water, h summary of the treatment systems for the barite
facilities in this subcategory follows:
Source
Facility Discharge
2011
Intermittent* Well water
2012
2013
2015
2016
2017
2018
2020
2046
Intermittent* Mill tailings,
runoff
from clear
water pond
None from
tailings pond
None
Intermittent*
Intermittent*
Inte rmi ttent*
Intermittent*
Intermittent*
from clear
water pond
None from
settling pond
Intermittent*
from clear
pond
None from
tailings pond
None
Mill tailings
Mill tailings
Mill tailings,
runoff
Mill tailings,
runof f
Mill tailings,
runoff
Mill tailings,
runoff
Well water
Mill tailings
Well water
Mill tailings
tailings pond
2112 None	Slime Pond
~Indicates overflow due to heavy rainfall.
Treatment
Pond recycle,
18 ha (45 ac)
Pond 8 ha
(20 ac)
Pond, 36 ha
(90 ac)
Clarification
Pond, recycle
Pond, recycle
Pond, coagulation
Flocculation,
recycle
Pond, coagulation
Flocculation,
recycle
Pond, recycle
Pond, recycle
Pond 24 ha
(60 ac)
Pond, 2 ha
(6 ac)
Pond, 12 ha
(30 ac)
clarification
Pond, recycle
Pond recycle
49

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Effluent
In normal circumstances, there is no effluent discharge from
any of these facilities. During heavy rains six facilities
(2011, 2015, 2016, 2017, 2018 and 2020), have an overflow
from the impoundment area. Facilities 2012 and 2046 have no
overflow from their tailings impoundment area. However,
during heavy rainfall, they do have overflow from clear
water ponds. Due to its geographical location, facility
2013 has no pond overflow. The amounts of these
intermittent discharges are not known.
Data concerning tailings pond effluent after heavy rainfall
was obtained from one facility. The significant
constituents in this effluent are reported as follows:
Facility	2011
Daily Avg. - Max.
pH	6.0	-8.0
TSS, mg/1	15	32
Total barium,
mg/1	0.1	- 0.5
Iron, mg/1	0.04	- 0.09
Lead, mg/1	0.03	- 0.10
BARITE (FLOTATION PROCESS)
Process Description
Processing in these facilities consists of crushing the ore
to free it from the gangue material, washing the barite ore
to remove the clay, jigging the washed ore to separate the
gravel, grinding and beneficiation by froth flotation to
recover barite concentrates. The concentrates are then
filtered and dried. Drying at these facilities is conducted
at temperatures high enough to destroy the organic reagent
used in the flotation. The dried product is then cooled and
bagged for shipment.
At facility 2019, two separate flotation circuits are used
to recover barite fines from the log washer and jig
tailings. In facility 2014, the ore from the mine is free
from clays and sands, and this facility processes its ore
without a washing and jigging operation. A generalized flow
diagram for this subcategory is given in Figure 11.
Raw waste Loads
The major process raw waste emanating from these facilities
is the flotation mill tailings. The disposition and the
quantities of the wastes are given as follows:
50

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WATER
RECYCLED
WATER
SOLID SLIME
WASTE SALVAGE
GRAVEL SLIME
TO SALVAGE
WASTE
WATER
SPRAY
X
U!
MILL,
CLASSIFY,
THICKEN
Ai\D
CONDITION
STEAM
REAGENTS
SPRAY
WATER
JL
x
FLOTATION
SECTION
FILTRATE
"O
1
$


THICKENING
CIRCUIT

FILTER,
DRY
AND
COOL
JiGGED
. 3A.RI7E
PRODUCT
'PRODUCT
RECYCLED
TO JIG
T
RECYCLED TO JIG AND CONDITIONING
TAiL'* iG3 FOND
FIGURE 11
BARITE MINING AND PROCESSING
(FLOTATION PROCESS)

-------
	1/dav (gal/day)
Facility
2010
20.14
2019
Mill tailings
530,000
(140,000)
660,000
(173,500)
4,730,000
(1,250,000)
Washdown water
from mill
265,000
(70,000)
110,000
(29,000)
unknown
Spent brine from
water softening
19,000
(5,000)
operation
The solids in the raw waste stream was reported to be an
average of 24,750 mg/1 and maximum of 50,000 mg/1 for
facility 2019.
Water Use
Facility 2010 consumes water at an average of 45,000 1/kkg
product (10,800 gal/ton) on a total recycle basis. This
includes about 1,655 1/kkg product used for non-contact
cooling, as boiler feed and for sanitary purposes. Most of
the process water used in this facility, 13,025,000 1/day
(3.44 mgd), is recycled back to the facility from the
thickening operations.
At facility 2014, well water is used both in the flotation
circuit and for the milling operation. This facility
consumes 2,500 1/kkg of product (595 gal/ton).
Approximately 35 percent of this water is recycled from the
thickening operations. The flotation tailings and some
overflow from the thickener are sent to the tailings pond.
At facility 2019 untreated river water is used as process
water. This facility consumes an average of 33,700 1/kkg of
product (8,900 gal/ton) on a once through basis.
The hydraulic load of these facilities are given as follows:
52

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Facility
Makeup water
Recycled water
Process consumed
Non-contact
cooling
Sanitary
Boiler feed
1/day (gal/day)
2010 ~ ~	2014
2,725,000 max. 792,000
(720,000 max.) (208,980)
13,025,000
(3,440,000)
15,750,000
(4, 160,000)
530,000
(140,000)
37,900
(10,000)
37,900
(10,000)
Brine & back flush 	
Srinse water used
in water softening
Misc. housekeeping 	
Waste Water Treatment
427,000
(112,520)
872,000
(230,000)
218,000
(57,500)
19,000
(5,000)
110,000
(29,000)
2019
4,731,000
(1,250,000)
4,731,000
(1,250,000)
Wastewater is treated by clarification and either recycled
or discharged. A summary of the treatment systems is given
as follows:
Facility Discharge
2010	Intermittent *
Intermittent
2014	None
None
2019	Intermittent «
Source
Mill tailings
Runoff, spills,
washdown water
Mill tailings
Washdown water
Mill tailings
Treatment
Pond, recycle
Pond
Pond, evapora-
tion and seepage
Pond, evapora-
tion and seepage
Pond
» Indicates overflow due to heavy rainfall
2 Overflow by facility to maintain pond level
Facility 2010 has two ponds with a total capacity of
16 hectares (40 acres) to handle the process waste water.
The flotation tailings are pumped into one of the ponds and
the clear water is pumped to the other pond. The mill
53

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tailings are in closed circuit, with occasional overflow
from the tailings pond. This overflow depends upon the
amount of surface water runoff from rainfall and the amount
of evaporation from this pond. The overflow varies from 0
to 760 1/min' (0 to 200 gpm). At times, there is no overflow
from this pond for a year or more. The clear water pond
catches the surface runoff water, some spills from the
thickener overflows, water from use of hoses, clear water
used in the laboratory, etc. This pond has also an
intermittent discharge varying from 0 to 380 1/min
(0-100 gpm).
At facility 2014, there are no effluent discharges from the
property. The mill tailings and the spent brine from the
water softening system are pumped into the tailings settling
pond and the washdown of the floors is pumped to a separate
pond. These ponds eventually dry by evaporation and
seepage. This facility has no problem in terms of pond
overflow due to its geographical location.
At facility 2019, process waste water is collected into a
large pipe which crosses under the nearby river into a
10 hectare (100 acre) pond. The pond water pH is maintained
at about 7.2 by application of lime. An overflow is
necessary from this pond to maintain a constant pond
elevation. The discharge from this pond is intermittent.
Of the 4,731,000 1/day (1.25 mgd) input to the pond, there
is an estimated 3,785,000 1/day (1.0 mgd) percolation
through the pond berm. The pond berm is built primarily of
river bottom sands. On a regular discharge basis (9 hours a
day and 4 1/2 days per week operation), the effluent
discharge from this facility would be 946,000 1/day
(250,000 gal/day). This pond is seven years old and has an
estimated life cycle of eighteen years. When overflow to
the river is desired, lime and ferric chloride are used to
decrease suspended solids.
Effluent Composition
Facility 2014 has no discharge. Facility 2019 has an
intermittent discharge in order to maintain a constant pond
elevation. The pond has yet to completely fill because of
seepage. Detailed information on this effluent is not
known. However, it has been reported that the average TSS
concentration in this effluent is 250 mg/1.
Facility 2010 has an occasional discharge both from the
tailings pond and the clear water pond during heavy
rainfalls. The significant constituents in these effluent
streams are as follows:
54

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Waste
Material
Tailings Pond
Daily Average
Max. Cone.
Amount
Clear Water Pond
Daily Average
Max. Cone.
(rcg/i)
kg/day (lb/day)
(mg/1)
TSS
TDS
Ammonia
Cadmium
Chromium
Iron, total
Lead, total
Manganese,
3-5
800-1271
<0.1-0.1
0.004-0.008
0.200-0.400
0.030-0.060
0.020-0.080
<0.5 (1)
<0.5 (1)
<0.5 (1)
1.8	(3.5)
467	(934)
<0.5	(1)
<0.5	(1)
0.100-0.120
0.030-0.070
0.040-0.090
3-6
1000-1815
5-35
total
Nickel, total
Zinc, total
0.002-0.008 <0.5 (1)
0.030-0.070 <0.5 (1)
0.005-0.010 <0.5 (1)
0.004-0.008
0.030-0.070
0.030-0.090
Mine Water Discharge
There is one underground mine in this category at
facility 2010. The other mining operations are in dry open
pits.
The underground mine workings intercept numerous ground
water sources. The water from this mine is directed through
ditches and culverts to sumps in the mine. The sumps serve
as sedimentation vessels and suction for centrifugal pumps
which discharge this water to the upper level sump. This
mine water is neutralized with lime (CaO) for pH adjustment
and sent to a pond for gravity settling prior to discharge
into a nearby creek. The raw waste load from this mine is
estimated to be 897,000 1/day (237,000 gal/day).
Mine Water treatment
At facility 2010, the mine water and the runoff water are
chemically treated by hydrated lime in the open pit mine
sump. This facility has an automatic system with continuous
monitoring of pH for neutralization prior to effluent
discharge into the settling pond. The raw waste from the
mine has a pH of about 3.0. The pH is raised to 6-9 by
addition of lime and then pumped into a pond for gravity
settling. There are currently two ponds and a third pond
under construction to treat the mine discharge. Presently
one of these ponds is in use and the other one is being
excavated and cleaned so that it will be ready for use when
the first pond is filled.
Mine Water Effluent
There is an intermittent effluent discharge to a nearby
creek. The total annual effluent discharge is estimated to
be 760,000,000 1/yr (200,000,000 gal/yr). The significant
constituents in this effluent are reported to be as follows:
55

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Parameter
New
Facility Pond Verification
Data	Design	Sampling	
A1
Pb
Mn
Ni
Zn
TDS
TSS
S04
Fe, total
Fe, dissolved
PH
Acidity
Hardness
23
0.6
0.06
1.3
0.05
0.01
2.6
25
0.1
0.1
0.5
0.05
0.1
0.5
2.6
404
3920
4348
1167
1515
225
177
13.8
>0.2
156
1.52
2.1
The facility stated that the verification data reflect new
acid seepage from adjoining property. The column "new pond
design "represents the company's design criteria for
building the third pond.
There are fifteen significant facilities in the U.S.
producing either fluorspar concentrates and/or finished acid
grade and metallurgical grade fluorspar products. Six of
these facilities are wet heavy media separation (HMS)
facilities, producing both a finished product (metallurgical
gravel) and upgraded and preconcentrated feed for flotation.
Five facilities use froth flotation for the production of
fluorspar alone or fluorspar with other minerals (barite,
zinc, lead); three are fluorspar drying facilities drying
imported filter cakes in kilns or air driers, and one is a
fluorspar pelletizing facility, where spar filter cake is
pressed to pellets, dried and shipped,
FLUORSPAR - HEAVY MEDIA SEPARATION (HMS) OPERATIONS
Process Description
An HMS facility may serve two purposes. First, it upgrades
and preconcentrates the ore to yield an enriched flotation
feed. Second, it produces a quantity of finished product
(metallurgical grade gravel).
The ore is crushed to proper size in the crushing circuit,
then washed and drained on vibrating screens to eliminate as
much fines as possible. The oversize material from this
operation is recycled back to the screen. The undersize is
sent into a spiral classifier for recovery of a portion of
FLUORSPAR (SIC 1473)
56

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the flotation facility feed. The HMS cone feed consists of
the middle size particles resulting the from the screening
operation. The separatory cone contains a suspension of
finely ground ferro-silicon and/or magnetite in water,
maintained at a predetermined specific gravity. The light
fraction (HMS tailings) floats and is continuously removed
by overflowing a weir. The heavy particles (flotation feed)
sink and are continuously removed by an airlift.
The float overflow and sink airlift discharge go to drainage
screens where 95 percent of the medium carried with the
float and sink drains through the screen, is magnetically
separated from the slimes, and is returned to the circuit.
The float and sink products are passed over dewatering
screens and the water is pumped back to the facility. A
generalized flow diagram is given in Figure 12.
Raw Waste Loads
Raw wastes in this subcategory consist primarily of slimes
from fines separation. At five of the facilities in this
subcategory (facilities 2004, 2005, 2006, 2008 and 2009),
there is no waterborne waste discharge from the HMS process.
The water used in these facilities is recycled back through
closed circuit impoundments. At facility 2007 the raw
waste, consisting of the classifier overflow is discharged
into a settling pond prior to discharge. The average value
of the raw waste for facility 2007 is given as follows:
Waste Material	kq/kkq of product (lb/1000 lb)
slimes	340
Facility Water Use
Water consumption in these facilities ranges from 96 to 2700
1/kkg of feed to the facility (650-2300 gal/ton of feed).
The hydraulic loads for the HMS facility were not known in
two of the facilities (2008 and 2009) because the HMS and
flotation facilities are located at the same site. They are
operated as a combined unit and water consumption values
were available for the combined operation. The hydraulic
loads for the remaining facilities are given as follows:
water Consumption
Facility	~
1/kkg of feed (gal/ton)
1555	2iT 2ff06	2007
9,600 2,710 3,670 5,550
(2,300) (650)	(880)	(1,330)
57

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FLOTATION
FEED
TO
CRUSHING
AND
RECYCLE
TO WATER
CRUSHING FOR
AND RECYCLE
RECYCLE
FLOTATION
FEED
	OVERSIZE
	UNDERS!ZE
FIGURE 12
FLUORSPAR K>SNiNG.AND PROCESSING
(HM3 PROCESS)

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Water Treatment
At four of the facilities (2004, 2005, 2006 and 2008); the
process water from the thickener is pumped to either a
holding pond or reservoir and then it is pumped back to the
facility on a total recycle basis. At facility 2009, there
are four ponds to treat the HMS facility tailings. Three of
these ponds are always in use. The idle pond is allowed to
dry and then harvested for settled fluorspar fines. At
facility 2007 the HMS tailings enter a 1.8 hectare
(4.5 acre) pond which has eight days of retention capacity.
The water from this pond is then discharged.
Effluent Composition
There is no effluent discharge from five of the facilities
in this subcategory (2004, 2005, 2006, 2008 and 2009). The
significant constituents in the effluent from facility 2007
is given as follows:
kg/kkg of product
Waste Components mq/1	(lb/1000 lbf
Fluoride	3.0	0.04
TSS	10.0	0.13
Lead	0.015	0.0002
Zinc	0.09	0.0012
The average pH of this effluent is 7.8.
FLUORSPAR-FLOTATION OPERATIONS
Process Description
There are currently five fluorspar flotation mills in
operation in the U.S. Three of these operations are
discussed below. A fourth facility is in the startup stage
and operating at 30-40 percent of design capacity.
Information obtained on it is not considered to be
representative of its operation.
In froth flotation facilities, fluorspar and other valuable
minerals are recovered leaving the gangue minerals as mill
tailings. Facility 2000 recovers fluorspar, zinc and lead
sulfides. Facility 2003 recovers fluorspar only. At
facilities 2000 and 2001, lead and zinc sulfides are floated
ahead of fluorspar using appropriate reagents as aerofloats,
depressants and frothers. At facility 2000, barite is
floated from the fluorspar rougher flotation tailings.
59

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In all these facilities, steam is added to enhance the
selectivity of the operation. The various grades of
concentrates produced are then stored in thickeners until
filtered. Barite, lead sulfide, and zinc sulfide
concentrates are sold in filter cake form. The fluorspar
concentrates are dried in rotary kilns. The dried
concentrates are then shipped.
At facility 2001, a portion of the fluorspar filter cake is
sent to -the pellet facility where it is mixed, pressed to
pellets, dried and stored. A generalized flow diagram for
flotation operation is given in Figure 13.
Raw Waste Loads
The process raw wastes in this subcategory consist of the
tailings from the flotation sections. At facilities 2000
and 2001, the tailings contain 14 to 18 percent solids,
which consist of 4-5 percent CaF2, 20-25 percent CaC03,
25-30 percent Si02, and the remainder is primarily shale and
clay. The average values of the raw wastes are:
kg/kkq of product (lb/1000 lb)
2000 ~ 2001	2003
flotation tailings	1,800 2,000 2,000
Water Use
The ores have different physical characteristics and require
different quantities of process water. A maximum of
20 percent of the process water is recycled from the
thickeners. The remainder is discharged into a ponding
system. The hydraulic loads for these facilities are:
60

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f
LEAD
SULFIDE
TO
RECOVERY
WATER
FOR
RECYCLING
MILL
TAILINGS
TO POND
BARITE
TO
RECOVERY
TAILING
TO
POND
WATER
FOR
RECOVERY
FIGURE 13
FLUORSPAR MINING AND PROCESSING
(FLOTATION PROCESS)

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Process
Boiler feed
Non-contact cooling
Dust control
Sanitary uses
Process waste
Water recycled or
evaporated
	i/day		
2000	2001
1,700,000
(0.45)
30,000
(0.008)
38,000
(0.010)
120,000
(0.032)
4,000
(0.001)
1,515,000
(0.40)
377,000
(0.103)
3,425,000
(0.905)
54,000
(0.014)
2,500
(0.0008)
3,260,000
(0.865)
196,500
(0.055)
2003
1,090,000
(0. 288)
54,500
(0.014)
0
1,144,500
(0. 302)
1/kkg of product	fgal/ton)
facility water use
process waste
11,900
(2,860)
9,540
(2,290)
20,200
(4,840)
19,100
(4,580)
21,030
(5,040)
0
Facility Waste Treatment
The waste water of the facilities in this subcategory is
treated in settling and clarification ponds. At
facility 2000, the mill tailings are pumped into a 7 hectare
(17 acre) settling pond for gravity settling. The overflow
from the settling pond flows into three successive
clarification ponds of 2.8, 1.6, and 2.4 hectares (7, 4, and
6 acres, respectively). The effluent of the third
clarification pond is discharged. settling in the third
clarification pond is hindered by the presence of carp and
shad which stir up the sediments. Experiments are in
progress using a flocculant in the influent line of the
second clarification pond to reduce the total suspended
solids in the effluent. These clarification ponds are
situated below the flood stage level of the nearby river,
and during flood seasons, the water from the river backs
into the ponds. Some mixing does occur but when flood
waters recede, most of the facility waste remains in the
ponds.
At facility 2001, the tailings from the fluorspar rougher
flotation cells, are pumped into a settling pond. The
overflow from the settling pond is discharged.
62

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Facility 2001 has a new 4 hectare (10 acre) clarification
pond with a capacity of approximately 106 million liters
(28 million gallons). The effluent from the first settling
pond will be pumped to the new clarification pond. A
flocculant will be added to the influent of the new pond in
quantities sufficient to settle the suspended solids to meet
the state specifications (TSS 15 mg/1). A portion of the
water from the clarification pond (approximately 20 percent)
will be recycled to the processing facility and the
remainder which cannot be recycled will be discharged.
Total recycle operation has been attempted on an
experimental basis by one of these operations for a period
of eight months, without success. The failure of this
system has been attributed to the complexity of chemical
buildups due to the numerous reagents used in various
flotation circuits.
The non-contact cooling water and the boiler blowdowns are
discharged at facilities 2000 and 2001 without treatment.
Facility 2003 mines an ore which is different from the ores
processed in the other two facilities. This facility
produces only fluorspar. The tailings from the mill go to
two settling ponds in series. The overflow from the second
settling pond is sent to the heavy media facility and there
is no discharge. A new pond is being constructed at
facility 2003.
Effluent
Facility 2003 has no discharge.
Effluents reported by facilities 2000 and 2001 for their
current operation and anticipated performance are:
pH
TSS
Fluoride
2000
Current
operation
7.2
500
5.1
concentratd
Antici- Current Antici-
operation pated
no change 8.2
30-60 1,800
5.1	9.8
no change
15-20
9.8
ZQQ0
Current Ł&tiŁi-
9Bgmi9P
2001
S3ŁŁSBt
Antisi-
TSS
4.8
0.29-0.57 34.4
0.29-0.38
63

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Fluoride
0.05 0.05	0.19 0.19
The results of verification sampling by the EPA contractor
are shown below:

2000
2001
PH
77r
87"
Alkalinity
359
340
Hardness
222
325
TSS
316
235
TDS
1056
1702
F
0.742
0.81
Fe (total)
5
2.9
Cd
0.13
0.02
Cr
0.11
0.05
cu
2.39
0.35
Pb
0.86
0.20
Mn
0.43
0.17
Zn
<0.01
1.13
FLUORSPAR-DRYING AND PELLETIZING OPERATIONS
Process Description
There are presently three fluorspar drying facilities in the
U.S. In these facilities imported filter cakes are dried
and sold. The filter cake has about 9-10 percent moisture
which is dried in kilns or in air driers. Two of these
facilities have no waterborne discharge. They use baghouse
collectors for dust control. The third drying facility is
located at the same site as the company's hydrofluoric acid
facility. This drying facility has an effluent from the wet
scrubber on the drier, which is treated in the gypsum pond
along with the acid facility effluent.
There are two pelletizing facilities in the U.S. One of
these operations has been discussed previously under
flotation (facility 2001). A second facility manufactures
fluorspar pellets only. At this facility fluorspar filter
cake is mixed with some additives, pressed to pellets, dried
and stored. No waterborne pollutants are generated at this
facility site.
Raw Waste Loads
No information was obtained on the wet fluorspar drying
operation discussed above because it is an integral part of
the hydrofluoric acid facility*s overall operation. The
combined effluent stream has been covered under the
Inorganic Chemical Manufacturing category.
64

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Facility Water Use
No water is used at these facilities and there are no
effluents, except for the facility combined with the
hydrofluoric acid manufacturing operation where the
discharge is attributable to the HF operation.
Waste Water Treatment
None is required.
Effluents
There is no discharge.
There are presently seven fluorspar active mines in the U.S.
Six of these mines are underground operations and one is a
dry open-pit mine. Additionally, there are three
underground mines in the development stage with no current
production and five other mines with no production but are
dewatered. The status and effluent discharge volumes from
these mines are given as follows:
1/dav fmctdl
Mines used for dewaterincr purpose, only
MINE DISCHARGE IN FLUORSPAR OPERATIONS
2080
2081
2082
2083
2084
no discharge
273,000 (0.072)
109,000 (0.029)
6,540,000 (1.73)
not pumped
Mines under development stage
2085
2086
2087
273,000 (0.072)
3,270,000 (0.86)
not pumped
Productive mines
2088
2089
2090
2091
2092
2093
2094
273,000 (0.072)
490,000 (0.13)
54,000 (0.014)
303,000 (0.080)
4,769,000 (1.26)
1,892,000 (0.50)
dry open pit
65

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Mine 2080 is used as an emergency escape shaft, air shaft,
and also to help dewater mine 2088. There are no discharge
waters pumped from either mines 2064 and 2087. What water
there is in these mines drains underground and eventually
enters mine 2083.
It has been estimated that at production stage mine 2085
will have a discharge volume in the vicinity of
3,800,000 1/day (1 mgd). The present discharge is only a
small fraction of the anticipated volume of water from this
mine.
At mines 2091 and 2093, about 62 and 40 percent,
respectively, of the mine discharge water is used at the
mills. The remaining drainage is then discharged.
Mine Water Treatment
At all mines, presently, the effluent stream is discharged
without any treatment into a receiving stream. Only
effluent from mine 2091 passes through a very small pond,
0.1 hectare (1/4 acre), prior to being discharged into a
creek. However, by 1975, after mines 2085 and 2092 are
fully developed, the effluent discharge emanating from these
mines will be treated in a settling pond to lower the
suspended solid concentrations. Presently, these mines have
low volume discharge, primarily mine seepage, which is
pumped to surface and discharged. It is expected that both
the effluent volume and the TSS concentrations will increase
after the ore body is tapped.
Effluent Composition
Verification sampling of the significant constituents in the
effluents from fluorspar mines are reported as follows:

2081
2083
2085
aine settling
pond
2089
2090
nine
2092
settling
pond 2093*
pK

7.6
7.6
7.4
8.1

7.9
8.0

Alkalinity

224
276
216
864

210
197

Hardness

336
1600
1600
221

235
222

CI

35
185
162
48

23
17

TSS
483
2
15
29
135
4
53
20
17
TDS
697
478
3417
1753
583
536
379
364

S04
:5
107
480
575
61
56
38
32

F
0.223
0.14
0.25
0.249
0.23
0.195
0.102
0.103

Fe
4.27
0.05
0.66
0.26
2.0
0.05
1.33
0.50
0.9
Pb
3.0
0.2
0.2
0.2
0.2
0.2
0.2
0.2
0.075
Mn
0.16
0.05
0.05
0.62
0.11
0.01
0.18
0.18
0.1
Zn
6.42
0.76
0.01
5.26
0.06
0.5
0.17
0.08
0.235
*plant data
66

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Fluoride content; of 3.2 mg/1 was reported for two mines
(2085 and 2092). However, it is expected that the fluoride
levels in the discharge from these two mines will be lowered
after pumping of the mine water begins. Additionally, total
suspended solids values of 10-300 mg/1 were reported for
mine 209 2, it is anticipated that the TSS value for this
discharge will be increased and possibly exceed the maximum
reported value due to the increase of the underground
activity.
Hydrogen sulfide concentrations up to 0.37 mg/1 has been
detected in the effluent of mine 2085. It has been reported
that the H2S content in the effluent has been steadily
decreasing since an H2S pocket was encountered.
67

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SALINES FROM BRINE LAKES (SIC 1474)
The extraction of several mineral products from lake brines
is carried out at three major U.S. locations: Searles Lake
in California, Silver Peak, Nevada, and Great Salt Lake in
Utah. The operations at these locations are integrated and
the water and waste handling cannot be readily attributed to
the separate products. The facilities at Searles Lake
operate what is called the "Trona Process", not to be
confused with the trona ore mining in Sweetwater County,
Wyoming, discussed elsewhere. This complex process produces
many products based on the brine constituents. The process
operated at Great Salt Lake produces a smaller number of
products. However, the waste handling and disposal
techniques at all locations are quite similar.
SEARLES LAKE OPERATIONS
Process Description
Several minerals such as borax, lithium salts, salt cake,
natural soda ash and potash are produced from the brine of
Searles Lake, California, by a series of processing steps
involving evaporation of the brine in stages with selective
precipitation of specific ingredients. The recovery
processes and raw material are unique to this location.
These processes are carried out in a desert area adjacent to
Searles Lake, a large residual evaporate salt body filled
with saline brines. About 14 percent of the U.S. potash
production is from this source, 74 percent of the U.S.
natural sodium sulfate, 17 percent of the U. S. borax, and
12 percent of the natural soda ash.
At facility 5872, the brines are the raw material and are
pumped into the processing facilities where the valuable
constituents are separated and recovered. The residual
brines, salts and end liquors including various added
process waters are returned to the lake to maintain the
saline brine volume and to permit continued extraction of
the valuable constituents in the return water. There is no
discharge as the recycle liquors are actually the medium for
producing the raw material for the processes. Total brine
into the facility is about 33,600,000 1/day (9.0 mgd) with
about one quarter being lost by evaporation. The total
recycle back to the salt body is the same volume, including
added process waters. The salt body is actually two
deposits separated by a layer of muds, and each deposit
contains brines of different typical compositions:
68

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constituent	upper structure brine
~	~ ~ welgfit
percent
KCl
Na2C03
NaHCof
Na2B407
Na2B404
Na2S04
Na2S
Na3A504
Na3P04
NaCl
water (by difference)
W03
Br~
I-
F-
Li20
4.90
4.75
0. 15
1.58
6.75
0. 12
0.05
0. 14
16.10
65.46
0.008
0.085
0.003
0.002
0.018
lower structure brine
wexgEt ~
percent
3.50
6.50
1.55
0.75
6.00
0.30
0.05
0.10
15.50
65.72
0.005
0.071
0.002
0.001
0.009
For potash production at Searles Lake, a cyclic evaporation-
crystallization process is used in which about
16,350,000 1/day (4.32 mgd) of saline brine are evaporated
to dryness. The brine, plus recycle mother liquor, is
concentrated in triple effect steam evaporators to produce a
hot concentrated liquor high in potassium chloride and
borax. As the concentration proceeds, large amounts of salt
(NaCl) and burkeite (Na2C03, Na2S04) are crystallized and
separated. The former is returned to the salt body and the
latter, which also contains dilithium sodium phosphate is
transported to another process for separation into soda ash
(Na2C03), salt cake (Na2S04), phosphoric acid and lithium
carbonate. The hot concentrated liquor is cooled rapidly in
vacuum crystallizers and potassium chloride is filtered from
the resulting slurry. Most of the potassium chloride is
dried and packaged while a portion is refined and/or
converted into potassium sulfate. The cool liquor, depleted
in potassium chloride, is held in a second set of
crystallizers to allow the more slowly crystallizing borax
to separate and be filtered away from the final mother
liquor which is recycled to the evaporation-concentration
step to complete the process cycle. The borax, combined
with borax solids from the separate carbonation-
refrigeration process, is purified by recrystallization,
dried, and packaged. A process flow sheet is given in
Figure 14.
69

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FIGURE 14
MINERALS RECOVERY FROM SEARLES LAKE

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Raw Waste Load
The wastes from the basic evaporation-crystallization
process, including the processes for potassium chloride,
borax, soda ash, and salt cake, are weak brines made up of
process waters, waste salts and end liquors. These are
returned to the salt body in an amount essentially equal to
the feed rate to the process—about 16,350,000 1/day
(«».32 mgd) . The recycle liquors enter both the upper and
lower structures of the salt body. In the case of the
carbonation-refrigeration system, the entire brine stream,
depleted in sodium carbonate and borax, is recycled to the
salt body to continue the solution mining.
Water Use
The overall water usage for the two facilities is about
33,600,000 1/day (8.88 mgd) of Searles Lake brine plus about
one-third of this volume of fresh water used for washing
operations.
Waste Water Treatment
As the evaporation-crystallization process involves only
recovery of salts from natural saline brines, with the
addition of only process water, the only wastes are depleted
brines and end liquors which are returned to the salt body
without treatment. The same considerations apply to the
carbonation-refrigeration process.
Effluent and Disposal
The only wastes are depleted brines and end liquors which
are returned to the brine sources. There is no discharge of
water.
GREAT SALT LAKE RECOVERY OPERATIONS
Process Description
At the present time four mineral products are produced at
this location: sodium chloride, sodium sulfate, potassium
sulfate and bittern liquors. Recovery of pure lithium and
magnesium salts is being planned for the future. About
20 percent of the U.S. natural sodium sulfate comes from
this location.
Brine from the north arm of Great Salt Lake is pumped into a
series of evaporation ponds. Partial evaporation occurs
selectively precipitating out sodium chloride. The residual
brine is pumped to a second series of ponds for further
evaporation and the precipitated salts are harvested.
71

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In the second series of ponds, further evaporation of the
brine occurs to precipitate sodium sulfate. The
concentrated residual brine is pumped to a third series of
ponds and the sodium sulfate is harvested, in the third
series of ponds, further evaporation occurs effecting
precipitation of potassium sulfate. The residual brine is
then pumped to a fourth series of ponds for bittern recovery
and the potassium sulfate is harvested.
The harvested raw salts are treated in the following manners
prior to shipment:
(a)	Sodium chloride is washed with fresh water, dried, and
packaged.
(b)	Sodium sulfate is treated in the same manner as sodium
chloride.
(c)	Potassium sulfate is dissolved in fresh water,
recrystallized from solution, dried, and packaged.
The washwaters from the sodium sulfate and chloride
purifications and waste water from the recrystallization of
potassium sulfate are discharged to the Great Salt Lake. A
process flowsheet is given in Figure 15.
Raw Waste Load
The raw wastes from the process consist of salts present in
the original lake brines which are lost during the washing
and recrystallization operations. There is also some
discharge due to yearly washout of the evaporation ponds
with fresh water. These are all returned to the Great Salt
Lake. The amounts of materials lost by these routes has not
been provided.
Water Use
Facility water intake includes lake brine, well water and
municipal reservoir water:
1/dav	(mgdi
Great Salt 163,000,000 (13.0)
Lake brine
municipal	11,000,000	(2.9)
reservoir
well	1,900,000	(0.5)
72

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—I
u>
GREAT
SALT
LAKE WASHOUT
BRINE WATER
WATER-
D1SSOLVER
EVAPORATION 	.J EVAPORATION
PONDS
WATER
i
WASHING
AND
DRYING
WASTE WATER TO LAKE
EVAPORATION
PONDS
WATER
WASHING
DRYING
PARTIAL
EVAPORATION
\—-5w FILTRATION
	Ł5^
LICUOR
TO f&ND
K2S04
PRODUCT
BITTERN
SOLIDS
PRODUCT
» NaC!
PRODUCT
¦O Naz SO4
PRODUCT
WASTE WATER
TO LAKE
FIGURE 15
MINERALS RECOVERY AT GREAT SALT LAKE

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The consumption of water is as follows:



evaporated
163,000,000
(43.0)
discharged
11 ,000,000
(2.9)
boiler
910,000
(0.24)
Also small amounts of water are used for sanitary purposes.
Wastewater arises from two sources: washing of the
recovered sodium chlorides and sulfate, and
recrystallization of recovered potassium sulfate. The waste
water from these operations contains these three substances
as constituents along with minor amounts of materials
present in lake brine bitterns (i.e., magnesium salts).
Since the waste water constituents are similar to the lake
brine, these wastes are discharged without treatment back to
the Great Salt Lake. The compositions of the intake brine
and effluent wash water are, in terms of mg/1:
lake brine	facility discharge
sodium	96,800	33,450
magnesium	49,600	99,840
chloride	160,000	78,000
sulfate	14,500	55,500
TSS	1945	703
The effluent consists primarily of sodium chloride.
However, this is variable since much more NaCl is recovered
than is saleable. Only the saleable material is retained.
The balance is washed back to the brine source.
Waste Water Treatment
The waste water brines are discharged back to Great Salt
Lake without treatment. This is necessary to maintain the
lake volume.
Effluent and Disposal
There is no discharge other than the waste brines which are
returned to the lake source.
74

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SILVER PEAK, NEVADA, OPERATIONS
Process Description
This facility manufactures lithium carbonate. Brine
containing lithium salts is formed by solution mining an
underground source and pumped to the surface to form a
man-made brine lake. This consists of a series of
evaporation ponds for preliminary concentration. After this
step, the brine is then treated with lime to precipitate
magnesium salts as the hydroxide. The magnesium hydroxide
is recovered periodically from the ponds as a solid waste.
The treated brine is then further concentrated by
evaporation to partially precipitate sodium and potassium
salts. These are periodically harvested from the ponds and
stored for future processing to recover potash values, and
the concentrated brine is again reacted with soda ash and
the lithium carbonate formed is filtered, dried, and
packaged. The spent brine is returned to the preliminary
evaporation ponds for mixing with fresh material. A process
flowsheet is given in Figure 16.
Raw waste Load
Process raw wastes listed below consist of magnesium
hydroxide sludges and precipitated sodium and potassium
chlorides. The magnesium hydroxide sludge is currently
disposed of by land dumping and the mixture of alkali
halides is land stored for future processing to recover
potash.
Water Use
Facility water consists of brine from an underground source
and fresh water used for washout purposes. All of this
water is evaporated during the process and all of the wastes
produced as solids.
Waste
kg/kkg of product (lb/1000 lb)
Magnesium hydroxide sludge
NaCl and KCl
680
187,000
Process washout water
Process brine
1/kkq of product (cral/ton)
1,500,000 (360,000)
36,800 (8,500)
75

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LIME
BRINE _____
FROM WEO.S
Ov
LIME
SODA ASH
VENT
t
PRELIMINARY
EVAPORATION
—**
REACTION
POND

SECONDARY
EVAPORATION

REACTOR
a?:d
FILTER
i .-gn
FILTER
AND
DRY



1
Wg(0H)2 .
(SOLID WASTE)
f
SOL'DS
(N«CI, KCi)
TO STORAGE

!
f
(SOLID WASTE)
LIQUOR

LITHIUM
-CARBONATE
FRODUCT
FIGURE 16
LITHIUM SALT RECOVERY
NATURAL BRINE, SILVER PEAK OPERATIONS

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BORAX (SIC 1474)
The whole U.S. production of borax is carried ou-t in the
desert areas of California by two processes: the mining of
borax ore and the Trona process. This latter process is
discussed in detail in the section on salines from brine
lakes. The mining of ore accounts for about three-fourths
of the estimated U.S. production of borax. The facility
discussed herein is the only U.S. producer by this method.
Process Description
Borax is prepared by extraction from a dry mined ore which
is an impure form of sodium tetraborate decahydrate (borax).
The ore is crushed, dissolved in water and recycled mother
liquor, and the solution is fed to a thickener where the
insolubles are removed and the waste is sent to percolation-
proof evaporation ponds. The borax solution is piped to
crystallizers and then to a centrifuge, where solid borax is
recovered. The borax is dried, screened and packaged and
the mother liquor recycled to the dissolvers. A process
flow diagram is given in Figure 17.
Raw Waste Load
Wastes from this process at the facility consist of 800 kg
of insolubles per kkg of borax product from the ore. This
amount is independent of startup and shutdown operation.
Water Use
Fresh water consumption at the facility amounts to
2,840 1/kkg (680 gal/ton). An additional 835 1/kkg
(200 gal/ton) enters via the ore. Most of the cooling water
is recycled and all the process waste water is fed to
evaporation ponds. The consumption of water in detail is:
77

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WASTE VWER
FIGURE 17
BORATE MINING AND PROCESSING

-------
process consumed
process waste discharge
contact cooling discharge
non-contact cooling discharge
boiler feed
sanitary
road conditioning
not otherwise allocated
total consumption
Waste Water Treatment
1/kkq of product
iaal/tofil
668 (160)
1,630 (390)
313 (75)
104 (25)
296 (71)
25 (6)
271 (65)
367 (88)
3,670 (880)
Present treatment consists of percolation-proof evaporation
ponds.
Effluents
There is no facility effluent. The compositions in mg/1 of
the intake water and the waste water sent to the evaporation
ponds are:
alkalinity (total)
hardness (total)
(CaC03)
chloride
nitrogen (NO3-)
COD
BOD
intake water
188
3.5
176
3.5
<5
<5
to evaporation
ESQds
10,830
1,145
3,100
2.8
480
81
79

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POTASH (SIC 147H)
Potash is produced in four different geographical areas by
four different processing methods. These methods are:
(1)	Dry mining of sylvinite ores followed by flotation or
selective crystallization to recover potash as potassium
chloride from the sylvinite and dry mining of
langbeinite ores followed by leaching to recover potash
as langveinite from the ores. A portion of the leached
langbeinite, usually fines from product screening, is
reacted in solution with potassium chloride to produce
potassium sulfate and magnesium chloride. The latter is
recovered as a co-product or discarded as a waste.
These are the processes employed in the Carlsbad, New
Mexico, area operations.
(2)	Solution mining of Searles Lake brines followed by
several partial evaporation and selective
crystallization steps to recover potash as KCl. During
the several process steps, 12 other mineral products are
also recovered. This is discussed earlier.
(3)	solution mining from Utah sylvinite deposits. This
method is used to recover potash as a brine, which is
then evaporated. The solids are separated by flotation
to recover potassium chloride. The sodium chloride is a
solid waste.
(4)	Evaporation of Great Salt Lake brines. This process is
similar to the Searles Lake operation in that the brine
is evaporated in steps to selectively recover sodium
chloride and sulfate and potassium sulfate. The latter
product is purified by recrystallization. All of the
wastes from this process which consist of unrecovered
salts are returned to the lake. This is also discussed
earlier.
CARLSBAD OEPRATIONS
Process Description
There are two processes employed in the six Carlsbad area
facilities which account for about 84 percent of the U.S.
production of potash. One is used for recovery of potassium
chloride and the other for processing langbeinite ores.
Sylvinite ore is a combination of potassium and sodium
chlorides. The ore is mined, crushed, screened and wet
ground in brine. The ore is separated from clay impurities
in a desliming process. The clay impurities are fed to a
gravity separator which removes some of the sodium chloride
80

-------
precipitated from the leach brine and the insolubles for
disposal as waste. After desliming, the ore is prepared for
a flotation process, where potassium and sodium chlorides
are separated. The tailings slurry and the potassium
chloride slurry are centrifuged with the brines returned to
the facility circuit. These tailings are then wasted, and
the sylvite product is dried, sized and loaded for shipment
or stored for future shipment. A process flowsheet is given
in Figure 18.
Langbeinite is a natural sulfate of potassium and magnesium,
K2Mg2(S04)3, and is intermixed with sodium chloride. This
ore is mined, crushed, and the sodium chloride is removed by
leaching with water. The resulting langbeinite slurry is
certrifuged with the brine being wasted and the langbeinite
dried, sized and loaded for shipment or stored for future
shipment.
A portion of the langbeinite, usually the fires from sizing,
are reacted in solution with potassium chloride to form
potassium sulfate. Partial evaporation of a portion of the
facility liquors is used to increase recovery by returning
precipitated solids to reaction. The remaining liquor from
the evaporation step is either discharged to an evaporation
pond or evaporated to dryness to recover magnesium chloride
as a co-product. The disposition of the waste liquor is
determined by the saleability of the magnesium chloride
co-product and the cost of water to the facility. The
potassium sulfate slurry from the reaction section is
centrifuged with the liquor returned to the facility circuit
and the resulting potassium sulfate product is dried, sized
and loaded for shipment or stored for future shipment. A
simplified process flowsheet is given in Figure 19.
All six facilities at Carlsbad processing sylvinite ore are
described above. Only two process langbeinite. One
facility also processes and purifies langbeinite ore for
sale. In that case, the ore is dry mined, crushed and cold
leached to remove sodium and potassium chlorides. The
material is then washed free of clays, recovered, dried and
packaged.
Raw waste Loads
For sylvinite ore processing, the raw wastes consist largely
of sodium chloride and insoluble impurities (silica,
alumina, etc.) present in the sylvinite ore. In langbeinite
processing the wastes are insolubles and magnesium chloride.
A comparison of the raw wastes of two sylvinite facilities
(facilities 5838 and 5843) with langbeinite raw wastes
(facilities 5813 and 5822) is given below. Differences in
81

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BRINE
BRINE RECYCLE
T
WATER
ORE
oo
to
CR'JSH
AND
GRIND
DESLIME
AND
SEPARATE
BRINES
TO VV/'STE
TO RECYCLE

SLIMES
TO
WASTE
«
TAILINGS
WASTE
AND
BRINE
legend:
ALTERNATE
ROUTES
•PRODUCT
FIGURE 18
POTASSIUM CHLORIDE MINING AND PROCESSING FROM SYLV!N!TE ORE

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WASTE MUDS	SCUD WASTE
FIGURE 19
LANGBEINiTE MINING AND PROCESSING

-------
ore grades account for differences in the clay and salt
wastes:
Facility
kg/kkg_of_groduct {lb/1000 lb)
5838" " ~ 58l3
wastes:
clays
75
3,750
1,400
235
2,500
1,000
318
75
0
NaCl (solid)
NaCl (brine)
KCl (brine)
75
64 0
440
MgS04
K2S04
Facility
5813
5822
langbeinite process
conversion purification
wastes:
clays
NaCl (solid)
MgC12 (brine)
15-30
0
0-2,000
45
1,400
0
A small percentage of the wastes of facility 5838 is sold.
Part of the magnesium chloride from langbeinite processing
is periodically recovered for sale and part of the remaining
brine solution is recycled for process water. These brines
contain about 33 percent solids. The wastes consist of muds
from the ore dissolution and the wasted brines. The latter
brine can sometimes be used for MgC12 production if high
grade, low sodium content langbeinite ore is used. The
composition of the brines after K2S04 recovery is:
potassium
sodium
magnesium
chloride
sulfate
water
3. 29%
1.3$
5.798
18.5%
4.9*
66.7%
84

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Water Use
Water use at sylvinite ore processing facilities is shown as
follows:
1/kkg of product (gal/ton)
Facility	5838 		 111 1
input:
freshwater	6,420 (1,540)	1,750 (421)
brine	not known	3,160 (760)
use:
process contact	34,600	(8,300) 11,900 (2,900)
cooling	0	0
boiler feed	0	205 (50)
consumption:
process waste	6,420 (1,540)	4,710 (1,130)
boiler blowdown	0	205 (50)
total	6,420 (1,540)	4,915 (1,180)
Water use at langbeinite ore processing facilities is shown
as follows:
1/kkg of product (gal/ton)
Facility	5813 ~	~5822~
input:
fresh water	8,360 (2,000)	4,800 (1,200)
use:
leaching and washing 5,000 (1,200)	4,800 (1,200)
cooling	30,000 (7,200)	0
consumption:
process evaporation	0-1,670 (400)	0
process waste	0-1,670 (400)	4,800 (1,200)
cooling water evapora-	6,700 (1,600)	0
tion total	8,360 (2,000)	4,800 (1,200)
There are no effluent streams from either of the langbeinite
ore processing facilities. Much water is recycled or lost
during process evaporation steps. All waste water streams
from these facilities are fed to evaporation ponds from
which there are no discharges.
Waste Water Treatment
All waste streams from the sylvinite process are disposed of
on the ground surface with the exception of the wastes sold
from one facility. At the langbeinite conversion facility
85

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20-30 percent of the cooling water is evaporated. All the
process waste water from the langbeinite purification
facility is fed to an evaporation pond. All known deposits
of langbeinite ore in the U.S. are in southeastern New
Mexico.
Effluent
There is no discharge from the sylvinite or the langbeinite
facilities,. All wastes are land disposed on-site.
UTAH OPERATIONS
Process Description
Solution mining of sylvinite is practiced at two facilities
in Utah. The sylvinite (NaClr KC1) is solution mined and
the resulting saturated brine is drawn to the surface and
then evaporated to dryness in large surface ponds. The
dried recovered material is then harvested from the ponds
and separated by flotation into sodium and potassium
chlorides. The sodium chloride tailings are discarded as a
waste and the recovered potassium chloride is then dried and
packaged. A process flowsheet is given in Figure 20.
Raw Waste Load
The raw waste at facility 5998 consists of 640 kg of waste
sodium chloride per kkg of product from the
flotation-separation step. There are no other wastes.
Water Use
Fresh water is used for process purposes at facility 5998 in
the following amounts: 10,600,000 1/day (2.8 mgd) and
11,700 1/kkg (2,800 gal/ton). Water is used first on the
flotation circuit and then in the solution mining. The
resulting brine from these operations is evaporated and then
processed in for the flotation unit. There is no discharge
of process water.
Waste Water Treatment
All process water is evaporated. No treatment is needed.
Effluent and Disposal
There are no waste waters for discharge. The sodium
chloride raw waste is disposed of on land.
86

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WATER	WATER
SODIUM CHLORIDE
SOLID WASTE
FIGURE 20
POTASH RECOVERY BY SOLUTION MINING OF SYLVINITE

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TRONA (SIC 1474)
All U.S. mining of trona ore (impure sodium sesquicarbonate)
is carried out in Sweetwater County, Wyoming, in the
vicinity of Green River. The deposits are worked at four
facilities. Three not only mine trona ore, but also process
it to the pure sodium carbonate (soda ash). One of these
three facilities also produces other sodium salts using soda
ash as a raw material. The fourth facility has only mining
operations at this time, but plans to build a one million
tons per year soda ash facility on the site in the near
future.
The 1973 production of soda ash from these deposits amounted
to 3,100,000 kkg (3,400,000 tons). This corresponds to
about 5,800,000 kkg of trona ore mined (6,500,000 tons).
The facility data contained herein are current except for
facilities 5962 and 5976 which are appropriate to the 1971
period when the discharge permit applications were
processed.. The trona ore mining rate in 1971 was
approximately 4,000,000 kkg/yr (4,400,000 tons/yr). Rapid
expansion in capacity of these facilities has been taking
place in recent years and continues at this time.
Since the mining and ore processing operations are
integrated at these facilities, they are covered as a whole
by this analysis. All four facilities are represented in
the data.
Process Description
Mining Operations
The trona deposits lie well beneath the surface of this arid
region and are worked by room and pillar mining or longwall
mining at depths of 240 to 460 m (800 to 1500 ft) . The
broken ore is transported to the surface and stockpiled for
further processing. The mining is a dry operation except
for leakage from overlying strata through which the mine
shafts were sunk or from underlying strata under pressure.
All four facilities experience such mine leakage.
Ore Processing
The on-site refining process for trona ore consists of its
conversion to the pure sodium carbonate, called "soda ash".
The processing includes the removal of insoluble impurities
through crushing, dissolving and separation, removal of
organic impurities through carbon absorption, removal of
excess carbon dioxide and water by calcining and drying to
soda ash. Two variations of the process are used, the
88

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••sesquicarbonate" process and the "monohydrate" process. At
present all three soda ash refineries use the monohydrate
process. One also uses the sesquicarbonate process.
General process flow diagrams of both processes are shown in
Figures 21 and 22 with the raw materials and principal
products material balances given in units of kg/kkg soda ash
product.
These processes both require large quantities of process and
cooling water for efficient operation, but the arid climate
in this area (average annual precipitation of 7 to 8 inches)
allows for disposal of waste water through evaporation in
ponds.
Raw Waste Loads
Raw wastes from these operations come from three sources:
mine pumpout water, surface runoff and ground water, and ore
processing water. The wastes in the mine and surface water
are principally saline materials (dissolved solids) and
suspended solids picked up in the ground. These materials
are naturally present in the surrounding earth or the
aquifer. The ore processing raw wastes are principally the
impurities present in the trona ore plus some unrecovered
sodium carbonates, carbon, filter aids, and treatment
chemicals as well as any minerals entering with the makeup
water.
Mine Pumpout Raw Wastes
The average mine pumpout at these facilities ranges from
less than 19 to 1,140 1/min (5 to 500 gpm).
waste materials	5962	5976
(mg/l7
dissolved solids	74,300	11,500
suspended solids	369	40
COD	346	2.1
ammonia	not available 8.1
fluoride	n n
lead	" "	0.023
chloride	" "	1,050
sulfate	" "	655
Runoff and Ground Water Raw Wastes
High ground water levels during the March through August
period give a seasonal water flow in the 5962 facility con-
taining 2,160 kg/day (4,750 lb/day) of total solids, prin-
cipally dissolved solids. This particular ground water
problem apparently does not exist at the other facilities.
89

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SC3'J~2ER
i
7
D!SCHŁr
-------
I
t
Sc'*~DM*L
r>.' r.rr
FIGURE 22
TRQNA ORE FRCCESSi&G
BY THE SE3QUI CAREDM/^TE PROCESS

-------
Rainwater and snow runoff discharges are highly variable and
also contain saline dissolved solids and suspended solids.
Ore Processing Raw Waste
Unlike the foregoing wastes, the ore processing wastes are
principally related to the production rate and, hence, are
given on the basis of a unit weight of ore:
waste material
kq/kkq of ore (lb/1000 lb)
ore insolubles (shale and shortite)
iron sulfide (FeS)
sodium carbonate
spent carbon and
filter aids (e.g., diatomaceous
earth, perlite)
100-140
0-1
60-130
0.5-2
The composition of the mill tailings water flow from
facility 5933 to the evaporation ponds, is:
total dissolved solids:
total suspended solids:
total volatile solids:
chloride:
15,000 mg/1
2,000 mg/1
2,500 mg/1
3,400 mg/1
The Green River, which is the principal source of process
water for all three soda ash refining facilities, has the
following average characteristics measured in the third
quarter of 1974:
flow:	47,000 1/sec
pH:	8.6
total solids:	326 mg/1
total hardness:	127 mg/1
carbonate:	77 mg/1
calcium:	60 mg/1
magnesium:	6.4 mg/1
sulfate:	120 mg/1
chloride:	15 mg/1
silica:	5.1 mg/1
The Fontanelle Dam is upstream of the intakes of these
facilities and regulates the flow past these intakes to
smooth out natural variability.
Water Use
Water use at the mines having attached refineries is
determined principally by the refining process. The only
water associated with the mines is mine pumpout, dust
control water and sewage, the latter two being rather small.
92

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Water Intake
Water intake to the facilities comes principally from the
Green River (fresh water) and from mine pumpout (saline).
In some cases mine pumpout is used as part of the process
water and in others it is discharged to the treatment ponds.
The amounts of river water intake at the three soda ash
refiners are:
1/day	(mqd)	1/kkg of prod.
average intake	8.7x10* (2.3)	2,600 (630)
range of average intake 6.3-10.6x106	2,000-3,200
(1.7-2.8)	(180-760)
Mine pumpout for all four trona ore mining facilities are:
1/day (ntgd)
average flow	610,000 (0.17)
range of average flows 25,000-1,640,000
(0.007-0.13)
Relative flow per unit production values for the mine
pumpout are not useful since the flow is not influenced by
production rate.
There are three major routes of consumption of the water
taken in to these facilities: evaporation in the course of
refining via drying operations and cooling water recycling,
discharge of waste water to evaporation ponds (both process
and sanitary), and by discharge of wastes to waterways. The
consumption of water for the three soda ash refiners via
these routes is:
total consumption	1/day (mgd)	1/kkq of product
131 VtOQi "
average	9.3 x 10« (2.5)	2,810 (680)
range of averages	7.08-10.6 x 10*	2,250-3,200
(1.9-2.8)	(510-760)
evaporation in processing
average	3.1 x 10* (0.9)	1,100 (260)
range of averages	3.0-3.8 x 10*	910-1,200
(0.8-1.0)	(230-280)
net flow to evaporation ponds
average	5.8 x 10® (1.5)	1,800 (130)
93

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range of averages
4.1-6.8 x 10®
(1.1-1.8)
1,300-2,000
(320-490)
facility discharge of wast.es
average
range of averages
23,000 (0.006)	8 (2)
0-45,000 (0-0.012) 0-13 (0-3)
A significant variation in the above flows during the course
of a year would be the effect of increase in production rate
occasioned by a facility expansion.
Waste Water Treatment
Process waste waters go to tailings separation ponds to
settle out the rapidly settling suspended materials and then
to the final disposal ponds which serve principally or
wholly as evaporation ponds. Where process water discharge
takes place (at present only facility 5933), the overflow is
from these ponds.
The ground water and runoff waters are also led to
collection ponds where settling and large amounts of
evaporation take place. The excess of these flows at the
5962 and 5976 facilities is discharged.
Evaporation of the saline waste waters of these facilities
takes place principally in the summer months since the ponds
freeze in the winter. The net evaporation averaged over the
year apparently requires an acre of pond surface for each
2,000 to 4,000 gal/day (equivalent to 19,000 to 37,000 1/day
per hectare) based on present performance. Ponds forced to
operate at rates close to 47,000 liters per day per hectare
(5,000 gal/day per acre) are not adequate for this location.
Effluent
There is no discharge from facility 5999.
Process waste water is discharged only at the 5933 facility,
and plans are under way to eliminate this.
Facility 5976 only mines ore and discharges only mine water.
The facility 5962 discharge is only ground and runoff
waters. The waste constituents after treatment of the
discharge at 5933 were at the time of permit application:
E3/1
kg/day (lb/dav)
total solids	9,000
dissolved solids 8,300
suspended solids 700
860 (1,900)
793 (1,750)
67	(150)
94

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SODIUM SULFATE (SALT CAKE)
Sodium sulfate (salt, cake) is produced from natural sources
in three different geographical areas by three different
processing methods because of differences in the ores or
brines utilized. Salt cake is also recovered as a
by-product of numerous inorganic chemical industry
processes. The three mining processes are:
(a)	Recovery from Grea.t Salt Lake brines as part of a step-
wise evaporation process. Sodium chloride and potassium
sulfate are recovered as co-products. This process was
discussed in Salines from Brine Lakes.
(b)	Recovery from Searles Lake brines as part of an involved
evaporative series of processes which generate
13 products. This process was also discussed in Salines
from Brine Lakes.
(c)	Recovery from West Texas brines by a selective
crystallization process.
Sodium Sulfate from Brine Wells
There are two facilities in this subcategory.
Process Description
Sodium sulfate natural brines are pumped from wells, settled
to remove suspended muds and then saturated with salt
(Nacl). The brine mixtures are cooled to effect
precipitation of sodium sulfate. The precipitated solids
are recovered by filtration and the spent brine is fed to an
evaporation pond as a waste. The recovered solids are
melted, calcined to effect dehydration, cooled and packaged.
A process flowsheet is shown in Figure 23.
Raw Waste Load
The process wastes consist of brine impurities, salt and
brine muds. These are listed as follows:
process source	kq/kka (lb/1000 lb)
sodium chloride purification	430
sodium sulfate purification	112.5
magnesium	purification	700
chloride
muds	brine settling	not given not given
95

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VO
o\
SODIUM
SULFATE
BRiNE
WELL
STEAM VENT
* SETTLING
COOLING
AMD
SETTLING
LIQu'CF?
TO
EVAPORATION
POND

DRYING
PRODUCT
(ANHYDROUS)
FIGURE 23
SODIUM SULFATE FROM BRINE WELLS

-------
Water Use
Facility water use consists entirely of the brine employed.
The details are given below.
Water intake
type	1/day (cral/dav)	1/kkq	fgal/ton)
brine	819,000 (216,000)	9,029 (2,160)
All of -this brine goes to the process and thence to waste
with no recycle.
Treatment
All waste waters are fed to on-site evaporation ponds.
Effluent
There are no discharges due to total evaporation at the arid
locations involved.
Great Salt Lake Operations
This operation recovers salt (NaCl), potash (K2SOU), and
salt cake (Na2S04) from Great salt Lake brines. This was
discussed in Salines from Brine Lakes.
Searles Lake Operations
There are two facilities at searles Lake in California which
process a unique brine to recover sodium sulfate in addition
to a number of other products. These operations were
discussed in Salines from Brine Lakes.
97

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ROCK SALT (SIC 1476)
There are approximately 21 producers of rock salt in the
United states. Eleven facilities were visited representing
over 90 percent of the salt production. The operations and
the type of waste generated are similar for the entire
industry. The sources of waste and the methods of
disposition vary from facility to facility. This study
covers those establishments engaged in mining, crushing and
screening rock salt.
Process Description
The salt is mined from a salt dome or horizontal beds at
various depths by conventional room and pillar methods. The
face of the material is undercut, drilled and blasted and
the broken salt passed through a multiple stage crushing and
screening circuit. The products normally 1" and smaller are
hoisted to the surface for further screening and sizing and
preparation for shipment. The extent of the final crushing
and screening carried out on the surface varies and in some
cases practically all is done underground. See Figure 24
for a typical process flow diagram.
Raw Waste Loads
The waste water from these salt facilities consists
primarily of a salt solution of varying sodium chloride
content and comes from one or more of the following sources:
(1)	Wet dust collection in the screening and sizing steps,
(2)	Washdown of miscellaneous spills in the operating area
and dissolving of the non-salable fines,
(3)	Mine seepage.
98

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ROCK SALT
UNDERGROUND
mining
UNDERCUTTING,

DRILLING

AKD

BLASTING

«
40	LEGEND:
	 ALTERNATE OR
OPTIONAL PROCESS
ROCK
-0e» FRODUCT
MULTIPLE
STAGE
CRUSHING
AND
SCREENING
1
L
-------
The waste streams associated with the various facilities are
as follows:
Waste stream
Facility Type or Source
Volume
1/day (mad)
4010
4013
4026
4027
4028
none (no surface
operations)
none
washdown from screening 4,100,000
operations	(1.1)
mine shaft seepage
dust collector
washdown
a)	shaft seepage,
washdown & cooling
water.
b)	shaft seepage
150,000 (0.04)
500,000 (0.13)
60,000 (0.02)
33,000 (0.009)
Treatment
none
none
none
none
none
filtration
& chemical
treatment
4032	shaft seepage
4033	a) shaft seepage
b)	surface drainage
from waste storage
c)	general surface
drainage
4034	a) shaft seepage
b)	brine pond,
(surface drainage)
c)	process water
4035	shaft seepage
4038 none
Water Use
4,000 (0.001)
27,000 (0.007)
25,000 (0.007)
25,000 (0.007)
520,000 (0. 14)
310,000 (0.08)
10,000 (0.003)
insignificant
none
none
none
none
none
none
none
none
none
none
In the mining and processing of rock salt, water consumption
is variable due to the miscellaneous nature of its use.
Routine use is for cooling, boilers (heating) and sanitation
with a small volume consumed in the process for dissolving
anti-caking reagents. Variable volumes are used in dust
collection and washdown of waste salt including non-salable
fines from the operating areas. The following lists the
volume of intake water per unit of production for some of
the mining, crushing and screening facilities:
100

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Facility
Intake Water
1/kRg
of product
Igal/ton)
Source
4013
1285
(310)
waterway (91%)
wells.
4026
22
(5)
municipal
4027
122
(30)
Lake (90*)
municipal
4028
38
(9)
municipal
4034
11
(3)
municipal
Waste Water Treatment
Generally there is no treatment of the miscellaneous saline
waste water associated with the mining* crushing and sizing
of rock salt. Some of the facilities have settling ponds.
Facility 4028 is unique in that the mine shaft passes
through an impure brine aquifer and entraps hydrogen sulfide
gas. The seepage from this brine stream around the shaft is
contained by entrapment rings. The solution is filtered,
chemically treated and re-injected into a well to the
aquifer.
Effluents
The effluents from these facilities consist primarily of
waste water from the dust collectors, miscellaneous washdown
of operating areas, and mine seepage. The compositions of
some of the facility effluents expressed in mg/1 are as
follows:
101

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Parameter
Volume (gal/day)
TDS
Na
CI
TSS
S04
PH
Parameter
Volume (gal/day)
TDS
Na
CI
TSS
S04
PH
4013
1,080,000
4,660
1,840
2,820
trace*
trace
4033
20,200
30,200
11,900
18,500
trace**
4026
40,000
30,900
7,200
15,700
72
1,400
7.5
4027
132,000
not available
not available
18,000
150
370
6.5
4034
001
81,000
53,000-
112,000
002B
138,000
319,000-
323,000
not available not available
32,000-
69,000
470-4,050
208
8.5-9.0
182,000-
191,000
1,870-4,750
260
7.6
* due to dilution
** runoff only, remainder of waste re-injected to well.
The suspended solids content in the process water discharges
from facilities 4013, 4026, and 4027 range up to 0.02 kg/kkg
of product. At least one of these facilities discharges an
average of as little as 0.002 kg/kkg of product.
102

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PHOSPHATE ROCK (SIC 1475)
Phosphate ore mining and processing is carried out in four
different regions of the United States. These areas and
their contribution to the total output are as follows:
(a)	Florida	7856
(b)	Western states 12%
(c)	North Carolina 5%
(d)	Tennessee	5%
Eighteen to twenty different companies with about 25 to 30
operations account for greater than 95 percent of the
output. Data collected through in-facility visits to most
of the operating facilities is analyzed in this section.
Phosphate ore is mined using various surface mining methods
and the extent of processing is dependent upon the
characteristics of the ore which is related to a particular
geographic area. The different phases of processing may be
classified as follows:
(a)	mining
(b)	mining - slimes separation
(c)	mining - slimes separation - flotation
Eighty-three percent of the industry processes the ore
through flotation. The major wastes associated with
phosphate production are the slimes and flotation tailings
which consist primarily of clays and sands. These are
separated from the phosphate rock through various processing
techniques such as grinding, screening, crushing,
classification, and finally, desliming or a combination of
desliming and flotation. This type of waste is common to
all processing facilities although it may differ in physical
characteristics. Settling ponds are the method of treatment
used with variations in percent of process water recycled
and discharged effluent from pond overflow. The method of
processing does merit subcategorization in that economics
can preclude the extensive use of recycled water in
flotation processing.
PROCESSES - EASTERN
The Florida, North Carolina, and Tennessee producers of
phosphate rock contribute about 88 percent of the total U.S.
production. The major operations in these geographical
103

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areas were visited which represented 15 companies and
21 operating areas. All of these facilities have
intermittent or continuous discharge.
Process Description
A typical process description is presented along with
comments on those that are significantly different.
The ore which lies at varying depths from the surface is
mined from open pits by use of draglines and dumped into a
pit adjacent to the mining cut. The material is slurried
with the use of high pressure streams of water from
hydraulically operated guns and pumped to the beneficiation
facility where it enters the washer section. This section
separates the pebble phosphate rock from the slurry which is
accomplished by a series of screening, scrubbing and washing
operations. The coarse fraction termed pebble is
transferred to product storage and the fine phosphatic
material is collected and pumped to surge bins for further
processing.
The next step in the process is the removal by cyclones of
the -150 mesh fraction referred to as slimes, colloidal
clays and very fine sands, which are pumped to settling
ponds. The oversize material is transferred to the
flotation section, where it is conditioned for the first
stage flotation. The floated material may be stored "as is"
or de-oiled, conditioned and directed to a second stage
flotation. The phosphate rock product is dried and stored.
The tailings (sands) from the flotation steps are discharged
as a slurry to mined out areas for land reclamation.
Facilities 4006, 4008 and 4025, located in a specific
geographical area, do not include the flotation step. The
processing is complete after the washing and desliming
stages, and, in some cases, a final filtering of the
product. The locations of the mines are usually some
distance from the beneficiation facility and the ore is
brought in dry, as mined, by truck or rail.
Facility 4003 in another area of the United States differs
in processing from the general description in the first part
of the mill operation. The ore feed slurry is passed
through a multiple stage screening step separating the
-14 mesh for flotation and the oversize is discarded. The
mine operation is unique in that the ore lies some 30 m (100
ft) below the surface. To maintain a dry pit, it is
necessary to de-pressurize an underlying high yield artesian
aquifer. This is accomplished through use of a series of
deep well pumps surrounding the pit that removes sufficient
water to offset the incoming flow refilling the zone.
104

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See Figure
operations.
25 for the process flow diagram of Eastern
Raw Waste Loads
The waste streams associated with this category of phosphate
rock production along with their source and disposition are
as follows:
Waste
Primary Slimes
(3 to 5% solids)
Secondary Slimes
Sand Tailings
(20 to 30* solids)
Source
Desliming
cyclones
holding tanks,
secondary
desliming
Flotation Cells
Mine Pit Seepage Mine
Disposition
Settling ponds
Settling ponds
Mined out areas for
land reclamation
An intermittent and
indeterminate volume
discharged to a slimes
or tailings waste
stream
Dust scrubber
slurry
Dryers
Discharged to waste
streams
105

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FIGURE 25
PHOSPHATE MIMING AMD PROCESSING
EASTERN

-------
The wastes associated with the various facilities and their
quantities follow:
kq/kkq fib/1000 lbl of product
~Mine Pit Dust Scrubber
Facility
Slimes
Tailings
Seepage
I Slurry
4002
790
1380
yes

no
4003
370
840
yes

yes
4004a
information
not available
yes

yes
4004b
information
not available
yes

no
4005a
1180
900
yes

yes
4005b
1160
1290
yes

no
4006
1000
no
runoff
only
no
4007
no (a mine i
only)
runoff
only
no
4008
580
no
runoff
only
no
4005c
1050
1520
yes

yes
4015
1000
1000
yes

yes
4016
1300
1300
yes

yes
4017
860
2440
yes

yes
4018





4019a
770
2140
yes

yes
4019b
900
2610
yes

yes
4019c
1290
2100
yes

yes
4020a
1030
1230
yes

yes
4020b
1330
1570
yes

yes
4025
1010
no
runoff
only
no
In addition to the slimes and tailings, facility 4003
disposes of about 120 kq/kkq product as solid waste from the
initial stage of beneficiation.
Water Use
Almost all water used in the beneficiation of phosphate ore
is for processing purposes. Only minimal volumes are used
for non-contact cooling and sanitary purposes.
A typical usage is in the range of 41,000 1/kkg
(10,000 gal/ton) of product with a considerable variation
occurring within the various facilities. The wide range of
water usage may be attributed to the following reasons:
(1)	Operating procedures and practices
(2)	Weight recovery (product/ton of ore)
(3)	Percent of ore feed processed through flotation
(4)	Ore characteristics
(5)	Facility layout and/or equipment design
107

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A comparison of water usage in -the various facilities is as
follows:
1/kkg (gal/ton)
Percent
Facility
10® 1/dav
imadl
of
product
R;
4002
248.1
(65.5)
25,800
(6200)
85
4003
411.4
(108.7)
45,300
(10,900)
60
4004a
205.9
(54.4)
Not Available
74
4004b
121.9
(32. 2)
Not Available
74
4005a
246. 5
(65.0)
18,100
(4300)
95
4005b
107.7
(28.5)
14,200
(3400)
95
4005c
370.9
(98)
30,600
(7300)
95
4006
3.6
(0.96)
20,400
(4,900)
0
4007
none

none (mine only)
N/A
4008
76.3
(20.2)
18,400
(4,400)
66
4015
313.0
(82.7)
45,500
(10,900)
90
4016
182.1
(48.1)
31,800
(7600)
84
4017
726.4
(191.9)
91,400
(21,900)
90
4018
358.2
(94.6)
66,600
(15,900)
N/A
4019a
355.0
(93.8)
64,300
(15,400)
N/A
4019b
573.8
(151.6)
78,000
(18,700)
N/A
4019c
255.9
(67.6)
81,100
(19,400)
N/A
4020a
257.4
(68)
21,300
(5,100)
80
4020b
174.1
(46)
32,200
(7,700)
85
4025
24.5
(6.5)
25,500
(6,100)
80
The sources of the process water consist primarily of
recycle (from ponds) with additional makeup coming from
wells and natural streams. Generally no additional
treatment of the water is carried out prior to use.
Some facilities use well water for pump seal water (>2000
gpm) claiming that this is necessary in order to protect the
seals. Others, facility 4015 for example, use recycled
slime pond water with no problems. Some facilities also
claim that well water is necessary for air scrubbers on
dryers in order to prevent nozzle plugging and utilize the
cooler temperature of the well water to increase scrubber
efficiency. Other facilities also recycle this with no
apparent difficulty. Facility 4018 recycles this water
through a small pond that treats no other wastes.
Waste Treatment
The treatment of the process waste streams consists of
gravity settling through an extensive use of ponds. The
slimes which are common to all phosphate ore beneficiation
processes, although differing in characteristics, are the
major waste problem with respect to disposition. The slimes
at 3-5 percent solids either flow by gravity via open ditch
with necessary lift stations or are pumped directly to the
108

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settling ponds. The pond overflow is one of the primary
sources of the recycle process water. Those facilities that
include flotation discharge tailings at 20-30 percent solids
to a mined out area, settling occurs rapidly with a part or
all of the water returned to recycle and the solids used in
land reclamation. The pond sizes are quite large, 160
hectares (U00 acres) being typical. A single process
facility will have several such ponds created from mined
areas. Because the slimes have such a great water content,
they will occupy more space than the ore. Hence dams need
to be built in order to utilize the volume over the ponds
that is above ground level. Because of past slime pond dam
breaks, the constructyion of these dams is rigorously
overseen in the state of Florida. The treatment of the mine
pit seepage and dust scrubber slurries are handled similarly
to the other waste streams. Facility 4003 discharges some
of the mine pit pumpout.
Effluents
Effluents are intermittently or continuously discharged from
one or more settling areas by all of the beneficiation
facilities. Volumes of effluents are related to: (1) X
recycle; (2) total and frequency of rainfall; (3) surface
runoff; and, (4) available settling pond acreage. The pH of
the effluents from these facilities range from 6.2 to 9.1
with over 70 percent of the averages between 7 and 8.
The effluents from these facilities typically include not
only excess water from the process recycle system, but also
various amounts of incidental water. The data from 18 of
these facilities is given below in ascending order of
relative volume of discharge:
109

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total amounts, kg/kkg of

total discharge
product (lb/1000
lb)

1/kkg
suspended
phosphate

facility
Jgal/ton!
solids
as P
fluoride
4002
335 (80)
0.003
0.0006
0.0006
4003
1,102 (250)
.08
0.024
0.033
4004a
10,200 (2,440)
0.71
0.067
0.036
4004b
103,800 (24,900)
0.39
0.208
0.125
4005c
1,400 (335)
0.046
0.0007
0.0022
4005b
7,900 (1,890)
0.137
0.0103
0.016
4005a
9,990 (2,390)
0.140
0.025
0.023
4006
61,450 (14,700)
0.18
0.092
0.006
4015
9,470 (2,270)
0.65
0.032
0.020
4016
262 (63)
not known
0.0003
0.0005
4017
11,660 (2,790)
0.26
0.103
0.051
4018
12,600 (4,340)
2.68
0.212
0.034
4019b
720 (173)
0.007
0.0013
0.0012
4019a
960 (230)
0.008
0.0016
0.0017
4019c
1,680 (400)
0.016
0.018
0.0054
4020b
2,530 (610)
0.017
0.0028
0.0078
4020a
12,080 (2,900)
0.036
0.012
0.024
4025
102 (24)
est. 0.019
0.0005
not known
The above facilities are located in Florida, Tennessee and
North Carolina.
The asterisked value in the preceeding table for phosphate
in the discharge of facility 4019c is anomalously high due
to acid regulation problems during the period of the
sampling. For this reason, this data point is not
comparable to those of the remainder of the facilities and
hence not used further in the data analysis.
Sufficient data was available from the Florida phosphate and
processing facilities to analyze statistically. Normal and
logarithmic normal distributions were tested on individual
daily and the monthly averages for TSS. Figure 26 plots log
TSS (mg/1) versus probability for one facility. The higher
TSS values fit a straight line determined by a least squares
program very well. It is typically necessary to exclude
some values that obviously rapidly fall off the line
determined by the higher values. Furthermore the very low
values should not be equally weighted with the higher values
that do fit the straight line since the higher values
determine the 99 percent level of confidence and the limits
are indicative of the uppermost level of confidence and not
the lower.
110

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FIGURE 26
Normal Distribution of Log Tss
for a Phosphate Slime Pond Discharge
PERCl'NTA'GC
2%	5	10 15 20	30 40 bO 60 70	80 85 90	95	98%

-------
The following data summarize the results of the statistical
analyses:
PHOSPHATE EFFLUENT QUALITY
TSS, mg/1

Long
Monthly 99
Observed
Daily 99
Observe*

Term
Percentile
Monthly
Percen-
Daily

Average

Maximum
tile
Maximum
4002
9.2
30.5
26
97. 5
64
4004A (1)
9.7
31.0
14
59.4
50
4004A (2)
11.3
-
-
66.7
30
4004B (1)
13.5
93.0
53
73.6
103
4004B (2)
3.5
8.8
6
18.3
12
4004B (3)
2.5
12.5
5
9.2
10
4005A
18.1
39.7
29
62.5
75
4005B (1)
18.7
31.7
25
58.8
67
4005B (2)
16.0
26.8
22
44.6
35
4005C (1)
13.2
30.6
23
54.8
47
4005C (2)
15.0
-
-
92.2
55
4005C (3)
28.2
-
-
144.1
105
4 015(1)
15.8
26.3
18
35.2
36
4015 (2)
46.5
300.9
109
367
181
4015 (3)
14.9
-
-
23.0
20
4016
7.4
20.3
13
28.1
17
4018
158
798
453
1334
1072
4 019 A
7.0
20.2
13
57.3
41
4019B
5.6
32.9
18
40.3
33
4 019C
6.3
53.7
17
62.4
43
4020A
2.8
22.7
5
39.0
14
4020B
5.5
7.6
6
13.7
12
112

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Some caution must be exercised when reviewing the data. For
instance some of the data noted are weekly composites and it
can be expected that the daily variability will be somewhat
higher. Some of the analyses, on the other hand, were
performed on less than 12 data points. This was the case
for some monthly data. In these cases the 99 percent level
of confidence was typically never achieved.
In other cases poor sampling techniques were employed by the
facilities, and some data was not analyzed because of
facility admissions of improper sampling. In other cases
high TSS values resulted from erosion of the earthen
discharge ditch or the inclusion of untreated facility and
road surface runoff.
In addition to TSS, the slimes from beneficiation and
facility effluents contain radium 226 resulting from the
presence of uranium in the ores. Typical radium 226
concentrations in slimes and effluents are presented in the
following table:
Radium 226 Concentrations (pCi/liter)
Slime Discharge Effluent Discharge
Facility dissolved undis-	g/liter	discharge	dissolved	undis-
solved	point	solved
*82
4005
0.82
10.2
0.48
A-4*
0.66
0.26




K-4*
0.52
0.28




K-8*
0.68
0.28



*86



4015
00
•
&
1074
14.8
002*
0.02
0.56




003*
0.34
1.1
4016
2.0
97.6
3.2
001*
2.2
0.74
4017
0.60
37.7
3.85
001
0.24
0.74
hour composite sample
The concentration of total radium 226 appears to be directly
related to the concentration of TSS.
PROCESSES ~ WESTERN
The Western producers of phosphate rock contribute about
12 percent of the total U.S. production. All of the major
operations in this geographical area were visited. They
represent four companies and six different operating areas.
The higher net evaporation rate is the major factor
responsible for making it feasible to attain no discharge.
113

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Process Description
A description of the phosphate ore processing is presented
with mention made of those facilities that are significantly
different.
The bedded and inclined ore deposits lie at varying depths
and are mined by open pit methods. The mining methods
generally involve the use of scrapers, rippers and/or
drilling and blasting. The ore is transported to the
facility area by truck or rail where it enters the first
stage of beneficiation which consists of crushing and/or
scrubbing. Subsequent sizing is accomplished through
further crushing, grinding and classification, with the
sized feed being directed to the desliming section for
removal of the minus 325 material. These slimes are
discharged either directly to a tailings pond or through a
thickener. The underflow product from the desliming step is
filtered. The filtered material may be further processed
through a drying and/or calcining step prior to shipment.
See Figure 27 for the process flow diagram.
Facility 4022 is the only facility that includes a flotation
step. After the cycloning or desliming step, the material
is fed to a flotation circuit consisting of conditioning
with rougher and cleaner cells. The flotation tailings are
combined with slimes and thickened prior to being discharged
to the settling pond.
Facilities 4024 and 4030 do not beneficiate. The ore is
mined and shipped to other locations for processing.
Raw Waste Loads
The raw waste loads from this subcategory of phosphate ore
processing are the slimes. In the facility (4022) having
flotation, the tailings constitute a second waste stream.
In the mining area of all facilities the only waste water
occurring is normal surface runoff.
114

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VENT
&
SLIMES AND TAILINGS TO SETTLING POND
FIGURE 27
PHOSPHATE ttMivlG AND PROCESSING
WESTERN

-------
Waste
Facility Material
4022
4023
4029
4031
slimes combined
with tailings
slimes
slimes
slimes
Source
desliming
cyclones 6
flotation
cells
desliming
cyclones
desliming
cyclones
desliming
cyclones
kg/kkg (lb/1000 lb)
of product
1,700
500
484
580
The disposition of the wastes from these facilities is to
settling ponds. In the operations that have dryers and
calciners, the dust from the scrubber system is discharged
to the slimes waste stream.
Water Use
At all operations where ore beneficiation occurs, the
process water recycle is 65 percent or greater. Most of the
remaining percentage of water is tied into the settled
slimes. The overflow from the settling pond is returned to
the process. The water usage is almost totally for
processing (>95 percent) with only a minimal volume used in
other areas of the facility such as non-contact cooling and
sanitary. A comparison of water usage in each facility is
as follows:
1/kkg
(gal/ton)
Facility Product
4022
4023
4029
4031
11,200
(2,700)
3,500
(830)
5,000
(1,200)
8,300
(2,000)
Percent
Recycle
66
60
Makeup
water
Source
66
75
spring & wells
wells
wells
wells
Waste Water Treatment
The treatment of the process waste streams consists
typically of flocculation and gravity settling with some
facilities having a thickening stage prior to ponding. The
116

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slimes consist primarily of fine clays and sands. At
facility 4022, the flotation tailings (primarily sands) are
combined with the slimes with treatment common to the other
operations. The waste slurries vary in percent solids from
5 to 15. Generally a flocculating agent is added before
pumping to a thickener or directly to a settling pond. The
solids settle out rapidly and all of the pond overflow
except in the case of facility 4022 is returned to the
process. This facility received a discharge permit
stipulating no discharge and intends to have complete
recycle and/or impoundment of process water.
Effluents
Of the six facilities surveyed, only facility 4022 currently
has a discharge. Some part of the overflow and seepage from
the settling pond flows into a small retention basin which
occasionally discharges.
117

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SULFUR (FRASCH) (SIC 1477)
There are currently thirteen known significant U.S. Frasch
sulfur facilities producing molten sulfur. Two of these
facilities are located in anhydrite deposits and eleven on
salt domes. Two of the salt-dome facilities are offshore
operations. Only one of the offshore facilities is in
production. The second facility will resume operation in
1975.
All of these facilities are designed for a maximum hot water
generation capacity. The sulfur-to-water ratio varies
greatly from formation to formation, from location to
location, and from time to time. The latter occurs because
normally as a mine ages, the water to sulphur ratio
increases. Therefore, the quantity of water used in this
industry category is not determined solely by the quantity
of product.
More than 85 percent of the sulfur delivered to domestic
markets remains as a liquid, from well to customer. Liquid
shipments are made in heated ships, barges, tank cars and
trucks. Molten sulfur is solidified in vats prior to
shipment in dry form.
ANHYDRITE OPERATIONS
Process Description
A Frasch installation starts with a borehole drilled by a
conventional rotary rig to the top of cap rock. A steel
casing is lowered into the borehole. Drilling is then
continued into the sulfur formation. A liner, which has two
sets of perforations, is set from the surface into the
sulfur formation. The first set of perforations is several
feet from the bottom and the second set is about five feet
above the first set. A second pipe, of smaller diameter, is
placed inside the liner with the lower end open and a few
inches above the bottom. A ring-shaped seal is placed
around the smaller pipe between the two sets of perforations
to close off the circulation in the annular space of the two
concentric pipes.
Incoming water is treated either by hot lime or the cold
clarification process plus softening, and a portion goes to
the boilers. Steam from the boilers is used to superheat
the remaining water, superheated water, under pressure and
at a temperature of about 163°C (325°F), is pumped down the
annular space between the two pipes, and, during the initial
heating period, down through the sulfur pipe. The hot water
flows through the holes at the bottom into the
sulfur-bearing deposit. As the temperature rises, the
118

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sulfur melts. Because the liquid sulfur is heavier than the
water, it sinks to the bottom where it enters the lower
liner perforations. Pumping water down the sulfur pipe is
then discontinued. Following the direction of least
pressure, the liquid sulfur moves up through the small pipe.
Its upward motion is aided by the introduction of compressed
air through a one-inch pipe.
After reaching the surface, the liquid sulfur is collected
and pumped into steam-heated tanks or barges for direct
shipment to the customer or it is transported to a shipping
center.
In the start up of new and existing wells some hot water
will preceed the upcoming sulfur and this water will be
bled, in the case of estuary operations directly to surface
waters. This is called sealing water.
In addition to producing wells, "bleed-off" wells must be
drilled in appropriate locations to control dome pressure
and permit continuous introduction of hot water.
At facilities located in anhydrite deposits, the "bleed-off"
water is heated and reused in the system. In general,
50 percent of the process water used in these facilities is
recovered. The remainder is lost in the sulfur-bearing
formation. At facilities located on salt domes, the
"bleed-off" water is saline because of the association of
the sulfur deposits with salt domes. The bleedwater is the
major waste water of these facilities. Since the water is
too corrosive to reuse.
Removal of large quantities of sulfur from the formation
increases the voids and cavities underground. subsidence
and resulting compaction eliminate most of these void
spaces. Drilling muds are also used to fill some of the
areas already mined. Some of these facilities mix the
sludge generated from their water softening and treating
operation with clay and use it as a substitute drilling mud.
Generalized process diagrams for mines located in an
anhydrite deposit and in salt domes are given in Figure 28.
Raw Waste Loads
The process raw waste consists of	the sludge (primarily
CaC03) which originates from	the water purification
operation. The raw waste loads are	presented as follows:
119

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ro
O
TREATMENT
CHE.ViCALS
RAW
WATER
WATER
TREATING
PLANT

LEGENDI
?
SLOWDOWN
BLOWDOWN
1	
ANHYDRITE DEPOSITS
CONVENTIONAL SALT DOME OPERATION
PROPRIETORY SALT DOME OPERATION
SEA WATER
I
i
HEAT
EXCHANGERS
SULFUR
DEPOSIT
BLEED WATER
TO TREATMENT
AND DISPOSAL
MOLTEN
¦ SULFUR
PRODUCT
FIGURE 28
SULFUR MIMING AND PROCESSING
(FRA3CH PROCESS)

-------
Waste Material kg/kkg of product (lb/1000 lb)
II Facility	~ ~ 2020"	~	2095
Water softener 9.6	15.3
sludge
Facility Water Use
Facility 2020 consumes water at an average of 6,970 1/kkg
(1,670 gal/ton) of product, 50 percent of which is recycled
back to the system and the remainder is lost in the
sulfur-bearing formation. This includes about 5 liters of
non-contact cooling water per kkg (1.3 gal/ton) of product
used in their compressor circuit.
Facility 2095 uses on
(2,030 gal/ton) of product. It
this water from its bleedwells.
facilities is given as follows:
the average 8,470 1/kkg
recovers 40-60 percent of
The hydraulic load of these
Water Use
at Facility
l/day_imgd]_
2020
2095
process consumed
non-contact
cooling
sanitary
feed to boiler &
steam generators
49,000,000
(13.0)
30,300
(0.008)
62,000 (0.016)
744,000
(0.197)
3,785,000
(1.0)
unknown
unknown
unknown
Facility Waste Treatment
There are no waterborne process wastes emanating from these
facilities. The only waste from these facilities is sludge
which originates from the water purification operation, and
it is sent to a thickener where as much water as possible is
reclaimed for recycling back to the system. At facility
2020 approximately 90 percent of the thickener sludge is
used as an additive to the mud that is injected into the ore
body in order to improve the thermal and hydrologic
efficiency of the mine. The remaining 10 percent is pumped
into a settling pond for evaporation. At facility 2095, the
entire thickener sludge is used as drilling mud.
Facility Effluents
There are no process water effluents out of these
properties. The waste streams emanating from the boiler
operations (boiler blowdowns) are addressed under general
water guidelines in Section IX of this report.
121

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SALT DOME OPERATIONS
Process Description
The process is the same as -that described in Anhydrite
Operations.
Raw Waste Loads
Raw wastes from these operations come from five sources:
(a)	bleed water,
(b)	sludge from water treating and softening operations,
(c)	surface runoff,
(d)	mining water used in sealing wells, and
(e)	miscellaneous sanitary waste, power facility area waste,
cooling water, boiler blowdown, steam traps, and drips
and drains.
The bleedwater from the mines is saline and contains
dissolved solids which have a high content of sulfides. Its
quantity and chemical composition is independent of the
sulfur production rate. The sludge from the water treating
operations varies in chemical composition and quantity
depending on the type of water used in the process. In some
facilities, only drinking water and a small part of process
water is softened and sea water constitutes the remainder of
the process water. In other facilities, fresh water is used
as process water and a portion of the facility water is
softened by hot lime process prior to usage.
The amount of runoff is dependent upon rainfall, the
moisture content of the soil, and other conditions which may
not necessitate the discharge of rainwater. information on
runoff was supplied for four facilities. The runoff values
given below are based on a one-inch rain and 100 percent
runoff. The average yearly rainfall for these areas is
estimated to be 54 inches.
The quantities of raw wastes for eight of the ten known salt
dome sulfur operations are given as follows:
122

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b. Sludge from Water Treating and Softening Operations
TSS
Facility 1/dav fmgd)	pH	mg/1
2021

5,300 (0.0014
10.5
54,000
2022

136,000 (0.036)
	
	
2023
(1)
	
	
	
2024

380,000 (2)
(0.10)
11.0
455
2025
(3)
1,136,000
(0.30)
6.6 - 7.1
20 - 55
2026

151,000 (0.040)
7.7
20
2027
(3)
3,000,000 (0.80)
10.0
60
2028
(3)
151,000 (0.040)
7.3
16
(1) Sludges and wastes from water treating operations were
included in the bleedwater waste stream.
(2) Includes boiler blowdowns.
(3) The raw waste streams in these mines are routed into
earthen ponds prior to discharge. Information presented
herein is the composition of the outfall from the pond.
Composition of the pond influent is not known.
c. Surface Rain Runoff
Information on surface rain runoff was not
facilities 2021 through 2024. Data for
facilities based on one-inch rain and runoff
as follows:
available for
the remaining
are presented
EaciU^Y_l/dag_l]ngdl
2025	223,000/000
(59)
2026	68,000,000
(18)
2027	125,000,000
(33)
2028	83,000,000
(22)
	ES_	
4.4 - 7.5
4.7 - 6.1
5.0 - 7.1
TSS
	5i2l_
20 - 40
90
30 - 265
d. Mining Water Used in Sealing Wells
Information on this waste stream was available for
facilities 2021 and 2024. In some facilities this waste is
separate from their bleedwater waste stream and in others
separate from the facilities miscellaneous wastes.
123

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Facility
2021
2024
Flow, 1/day (gal/day) 5r700 (1,500) 18,900 (5,000)
pH	7.9	7.5
TSS, mg/1	62	20
Sulfide, mg/1	7.8	57.2
BOD, mg/1	3.3	8.1
COD, mg/1	219	42
The waste stream for facility 2021 includes miscellaneous
treated sanitary waste, drips and drains.
e. Miscellaneous Power Facility Waste
In sulfur mines 2024, 2026, and 2027, the power facility
area waste is included in the waste stream originating from
the water treating and softening operation. In mine 2023,
the bleedwater waste stream includes the power facility area
waste stream. The flow rates and significant constituents
in the power facility area waste stream for the remaining
mines are given as follows:
Facility
2021
2022
2025
20 28
1/day 4,
600,000
57,000
1,150,000
230,000
(mgd)
(1.2)
(0.015)
(0.30)
(0.06)
PH
7.7
unknown
4.4-5.9
7.8
TSS,mg/1
56
unknown
20-40
44
Sulfide,




mg/1
0.0
unknown
Nil
Nil
BOD, mg/1
0.8
unknown
3.0
2.0
COD, mg/1
150
unknown
22
50
Mine 2022
is an
offshore operation and the composition
of
the wastes
for this
mine has not been
determined.

Water Loads




The details of the hydraulic loads at these facilities are
given below. Non-contact cooling water used in facilities
2025 through 2027 is on a 100 percent recycle basis.
124

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a. Water Intake. 1/dav fmord)
Water Source
Facility
Sea Water
River
Well
2021
80,400,000
114,000
	

(21.2)
(0.03)
	
2022
21,000,000
73,000


(5.6)
(0.019)

2023
40 1,900,000
33,300,000
	

(105.9)
(8.8)

2024
	
22,400,000



(5.9)

2025
	
29,000,000
18,200,000


(7.7)
(4.8)
2026
	
18,000,000
	


(<*.7)

2027
	
30,000,000
	


(8.0)

2028
— -
14,700,000
	


(3.9)

b. Water Use. 1/dav (gal/day)

Process
Non-Contact
Boiler

Facility
consumed
cooling
feed
Sanitary
2021
75,900,000
4,500,000
38,000
76,000

(20)
(1.2)
(0.01)
(0.02)
2022
21,000,000
760
53,000
19,000

(5.6)
(0.0002)
(0.014)
(0.005)
2023
428,000,000
7,600
6,300,000
114,000

(113)
(0.002)
(1.6)
(0.03)
2024
18,500,000
760
3,900,000
38,000

(4.9)
(0.0002)
(1.0)
(0.01)
2025
44,000,000
unknown
570,000
570,000

(11.5)

(0.15)
(0.15)
2026
17,500,000
unknown
280,000
320,000

(4.6)

(0.073)
(0.085)
2027
22,700,000
unknown
1,140,000
	

(6.0)

(0.30)

2028
13,600,000
unknown
130,000
650,000

(3.6)

(0.035)
(0.17)
Waste Water Treatment
The major waste from the sulfur mines is the bleedwater from
the formation. Due to the nature of the mining operation,
it is not possible to significantly reduce the quantity of
the bleedwater produced. Large aeration ponds are
considered to be the best technology available for treating
the water from the bleed wells. However, due to scarcity of
125

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land space for ponds near some of these mines, each
facility, with the exception of the offshore operation, uses
a unique treating system to reduce the hydrogen sulfide and
suspended solid concentrations in the bleedwater effluent
streams. A synopsis of the treatment technique used in each
mine follows.
Facility Bleedwater Treatment Technique
2021 Flash stripping of hydrogen sulfide and mixing of
partially treated bleedwater with a large volume of
oxygen containing seawater.
2022
Offshore operation - no treatment.
2023 Spray aeration to reduce hydrogen sulfide concen-
tration and then mixing of partially treated
bleedwater with a large volume of oxygen containing
seawater.
2024	Oxidation and settling ponds.
2025	Flue gas stripping of hydrogen sulfide and settling
ponds.
2026	Oxidation and settling ponds.
2027	Chemical treatment of hydrogen sulfides with
sulfurous acid and settling ponds.
2028	Oxidation and settling pond.
Details on the waste treatment techniques employed by each
mine are covered below.
Mine 2021
There are four waste streams at this facility. Outfalls #1
(power facility effluent), #2 (sludge from the domestic
water treating facility), and #5 (water from sealing wells,
miscellaneous sanitary waste and drips and drains) are
disposed of in a seawater bay leading into the Gulf without
any treatment. Outfall #3 (bleedwater) is first flashed
into a large open top tank which causes reduction in
hydrogen sulfide concentrations. After a short residence in
the tank, this effluent is mixed with seawater to effect
further oxidation of the hydrogen sulfides to sulfates and
to dilute it before discharge.
A flash stripping and oxidation system was chosen for this
facility primarily because of a new procedure of up-flank
126

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bleeding which precluded the continued use of the existing
treatment reservoir.
Mine 2022
The location of this mine, some 9.6 to 11.2 km (6 to 7
miles) offshore in the Gulf, does not lend itself to the
conventional aeration reservoir. Mechanical aeration
systems are considered undesirable by this company due to
the large quantities of gaseous hydrogen sulfide that would
be released to the atmosphere and come in contact with
personnel.
Presently, no treatment is given to the effluents discharged
into the sea. Some quantities of dissolved hydrogen sulfide
are swept out of the solution through gaseous evolution of
carbon dioxide and methane present in the formation water.
Additionally, a complete oxidation of sulfides occurs
through the reaction with the dissolved oxygen in the
seawater, and results of water sampling, since the mine
began operations, have shown an absence of sulfides within
150 m (500 ft) of the discharge points.
Mine 2023
Presently, there is only one major waste stream at this
facility. However, there are 6 other discharge points from
this facility primarily for rainwater runoffs. This mine
has three pumping stations in the field for rain water
runoffs which are newly designated discharge points. In
addition, there are 3 discharge points installed to cover
rainwater runoffs and the drips and drains from the levee
system around the power facility. This levee system has
been built to improve the housekeeping in the power facility
area.
The bleedwater from the mine is aerated in one of three
small reservoirs, located in the field area, prior to
pumping to the main treatment reservoir which is about
10 hectares (25 acres) in size. Here the water is sprayed
to reduce hydrogen sulfide concentrations. It is then
impounded for 3-4 days where further aeration occurs.
Finally, it is mixed with pumped-in seawater at a ratio of
20 to 1 in a 1830 m. (6000-foot), man-made canal to oxidize
any remaining sulfides to sulfates prior to discharge.
Power facility wastes are also piped into the canal where
temperatures are equilibrated and solids are settled.
Oxidation is effecting sulfide removal in this ditch rather
than just dilution as evidenced by the avearage reduction of
sulfide from 107 mg/1 to less than 0.1 mg/1 before and after
mixing with the seawater.
127

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A spray system was chosen for aeration in this facility due
to the lack of suitable land space for the construction of a
large conventional reservoir.
Mine 2024
Four discharge streams emanate from this facility.
Discharges #1 and #3, the power facility discharges and
mining water from sealing wells, respectively, discharged
into a river without any treatment. Discharge #2, the
bleedwater, flows by gravity through a ditch into a
50 hectares (125 acres) reservoir where oxidation of
hydrogen sulfide is accomplished. The effluent residence
time in this reservoir is about 15 to 18 days. The treated
bleedwater flows into a swift flowing tributary of a river
just before it enters tidal waters.
All sewage effluents entering into discharge #4, which is
primarily rain runoff, are treated through a septic tank
system prior to discharge.
Mine 2025
The bleedwater flows to a small settling basin from where it
is routed through a mixing zone. Sulfurous acid and
deposition inhibitor are added to the bleedwater in this
mixing zone and then the waste water is routed to packed
towers for hydrogen sulfide removal. In the packed towers,
the bleedwater flows counter current to cooled boiler flue
gas. The treated bleedwater is next aerated and sent to a
10 hectares (25 acres) settling basin. The overflow from
the settling basin flows through two 10-12 hectares (25 to
30 acres) each clarification ponds, prior to discharge into
the tidal section of a river through a 35 km (22 mile) long
disposal canal.
The effluents from the water softening and treating
operations are discharged into an earthen pond to settle the
solids and the sludge. The supernatant water from this pond
is discharged into a river. The solids are mixed with some
clay and used as substitute drilling mud. Rainfall runoffs,
boiler blowdown and other facility area wastes are
discharged without treatment. The sanitary waste is treated
in a septic tank system and then discharged into oxidation
ponds. The overflows from these ponds are discharged into a
river.
Mine 2026
In this mine, the bleedwater is treated in a series of three
ponds for settling and oxidation. Pond #1 is about
14 hectares (35 acres) and ponds #2 and #3 are about
128

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52 hectares (130 acres), each, in size. The overflow from
pond #1 flows through a 3.2 km (2 mile) ditch into pond #2.
The overflow from the third pond is discharged into a river.
Part of the rainfall runoff, a small part of the boiler
blowdown (the continuous blowdown is returned to the mine
water system), zeolite softener regeneration water, pump
gland water, and washwater are sent into a nearby lake
without treatment. The blowdown from the hot process
softening system and clarifier system is discharged to pits
where the excess supernatant is discharged with the
remaining rainfall runoffs into the creek. The settled
solids are used as drilling mud.
The sanitary waste of this mine is treated in a septic tank
system and reused in the mine water system.
Mine 2027
The bleedwater treatment process used consists of contacting
the waste water from the bleedwells with sulfurous acid with
provisions for adequate mixing followed with sufficient
retention time. Sulfurous acid is made both by burning
liquid sulfur or from hydrogen sulfide originating from the
bleedwater. In this process, the soluble sulfides in the
bleedwater are converted to elemental sulfur and oxidized
sulfur products in a series of reaction vessels. The excess
acid is next neutralized with lime and the insoluble sulfur
is removed by sedimentation. The effluent thus treated
passes through five basins in series having a total
retention capacity of about one day. The overflow from the
last basin is discharged into a salt water canal which flows
into the tidal section of a river.
The waste stream from the water clarification operation is
discharged into an earthen pond to settle the solids and the
sludge. The supernatant water from this pond is mixed with
boiler blowdown waste and other water treating facility area
waste streams prior to discharge into the salt water canal.
Rainfall runoffs are sent into the canal without any
treatment. The sanitary waste of this mine is treated in a
septic tank system and then discharged into a disposal
field.
Mine 2028
In this mine, the water from the bleedwells is sent into two
separate tanks from where it flows through 24 km (15 miles)
of underground piping into a ditch about 5 km (3 miles) in
length. From there it flows into a 325 hectare (800 acres)
pond for oxidation and settling. Treated effluent from this
129

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pond is discharged 6 0 days per year into a ditch. This is
because the canal water, while subject to tidal influence,
is selectively used for irrigation supply water.
The waste stream from the water clarifier and zeolite
softening operation is discharged into an earthen pond to
settle the solids and the sludge. The supernatant water
from this pond is intermittently pumped out into a creek.
The solids are mixed with some clay and used as drilling
mud.
Boiler blowdown water, facility area wastes and rainfall
runoffs are sent into a nearby creek. The sanitary waste of
this mine is treated in a septic tank system and then
discharged in a disposal field.
Effluent Composition
As indicated in the waste treatment section, the rainfall
runoffs, boiler blowdowns, waste resulting from the water
softening and treating operations, facility area wastes are
sent into receiving waterways without any treatment.
Therefore, the composition of these streams are as given in
the raw waste load section. The composition of the
bleedwater effluent from mine 2022 has not been determined
since a federal discharge permit was not required for
offshore operations until 1974. Table 5 compares the
discharges from these facilities.
130

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Plant	2021
Age 14
Location La *
Total Discharge, 10^
1/day _	74
Total Discharge 10
E	Vkkg	180
M	Bleedwater discharge,
10 1/day	4.6
Bieedv/ater discharge,
103 l./kkg	11.2
Pollutants (in total
discharge)
TSS, rrg/i	57
TSS, kg/kkg	10.3
Sulfide, rng/ 1	16
Sulfide, kg/kkg 2.9
TSS (seawater contribution
omitted) kg/kkg	4.8
* Bayou
TABLE 5
COMPARISON OF DISCHARGES
2023
2024
2025
2026
2027
2028
2029
2097
41
21
45
26
22
17
28
6
La *
La
Tx
Tx
Tx
Tx
Tx
Tx
428
19
38
17
23
11.5
8.7
11.5
260
6.9
12.1
20
20.5
21.5
11.8
22.1
27
19
38
17
23
11.5
8.7
11.5
16.4
6.9
12.1
20
20.5
21.5
11.8
22.1
33
95
30
20
5
40
50
30
8.6
0.7
0.4
0.4
0.1
0.9
0.6
0.7
0.4
51
rril
nil
nil
nil
not de-
2
0.1
0.4
nil
nil
nil
nil
tected
0.04
0.3
0.7
0.4
0.4
0.1
0.9
0.6
0.7

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MINERAL PIGMENTS (IRON OXIDES) (SIC 1479)
The category "mineral pigments" might be more directly
classified as "iron oxide pigments" as they are the only
natural pigment mining and processing operations found. The
guantity of natural iron oxide pigments sold by processors
in the United States in 1972 was just under 63,500 kkg
(70,000 tons) .
One minor processor and two processors of natural iron oxide
pigments were contacted. These three companies account for
approximately 20 percent of the total U.S. production.
Process Description
Iron oxide pigments are mined in open pits using power
shovels or other earth removing equipment. At some
locations these materials are a minor by-product of iron ore
mined primarily for the production of iron and steel. Some
overburden may be removed in mining.
Two processes are used, depending on the source and purity
of the ore. For relatively pure ores, processing consists
simply of crushing and grinding followed by air
classification. A drying step can be included (facility
3019). Facility 3022 and facility 3100 are dry operations.
Alternatively, for the less pure ores, a washing step
designed to remove sand and gravel, followed by dewatering
and drying is used (facility 3022). Solid wastes and
facility effluent waters may be generated in this latter
process. These processes are shown in Figure 29.
Raw Waste Loads
Water is not used in mining of iron oxides. Pit water, if
it collects, is dumped to the ground or goes to a sump in
the pit until the pit undergoes relcamation. Overburden is
used for fill, as are any other mining waste solids. In the
wet processing of iron pigments, the rake thickener overflow
is discharged to a settling pond, and the underflow, which
is wet oxide, is fed to a drum dryer (facility 3022).
Water Use
In the wet processing of iron oxide for pigment,
approximately 27,800 1/kkg product of water (6670
gallons/ton) is used (facility 3022). This process water is
obtained from a large settling pond with no additional
treatment. Approximately 95 percent of this water
(26,400 1/kkg of product or 6,330 gal/ton) overflows from
the rake thickener, and drains to the settling pond, while
132

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OVERS
MiNE
Co
CO


A


CRUSHER

rotary
DRYER |
ROLLER
MiLL
——
A!R
CLASSIFICATION
LOG
WASHER
RAKE
THICKENER
STEAM
!
'PRODUCT
DRUM

DRYER

PRODUCT
f
SOLID
WASTE
RECYCLE
POND
FIGURE 29
MINERAL PIGMENT MINING AND PROCESSING

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the remaining 5 percent (1,400 1/kkg or about 340 gal/ton)
is evaporated on the drum dryer.
Waste Water Treatment
In the wet processing of iron oxide pigments, water overflow
from the rake thickener drains to a large settling pond. It
is then recycled to the process with no further treatment.
Effluents and Disposal
Solid waste at the mine are used as fill for land
reclamation purposes. solid wastes (sand and gravel) are
obtained from the log washer. At facility 3022, these
wastes are sold. No significant amounts of solid wastes are
obtained from the dry process (facility 3019).
At facility 3022 the waste water is discharged to a
41 hectare (100 acres) settling pond which is also used for
effluent from a barite operation. The discharge from the
large pond is mainly attributable to the barite operations.
134

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LITHIUM MINERALS (SIC 1479)
There are two producers of lithium minerals, excluding brine
operations, and both sources are from spodumene which is
separated from pegmatite ores through the process of
flotation. The method of concentrating the spodumene and
the handling of the waste generated are very similar for
both facilities.
Process Description
The spodumene ore is produced from an open pit using
conventional methods of mining. The ore is sized for
flotation by passing through a multiple stage crushing
system and then to a wet grinding mill in closed circuit
with a classification unit. The excess fines in the ground
ore, the major waste component, are separated through the
use of cyclones and discharged to a settling pond. The
coarse fraction is conditioned through the addition of
various reagents and pumped to the flotation circuit where
the spodumene concentrate is produced. This primary
product, dependent upon the end use, is either filtered or
dried. The tailings from the spodumene flotation circuit
which consists primarily of feldspar, mica and quartz are
either discharged to the slimes-tailings pond or further
processed into salable secondary products and/or solid
waste. The secondary processing consists of flotation,
classification and desliming. The waste generated in this
phase of the operation is handled similarly to those in the
earlier steps of the process. A generalized diagram for the
mining and processing of spodumene is given in Figure 30.
Reagents used in these facilities are: fatty acids; amines;
hydrofluoric acid; sulfuric acid; and sodium hydroxide and
other anionic collectors. The flocculants used for waste
settling are alum and anionic-cationic polymers.
Raw Waste Loads
The two waste streams common to both facilities are the
slimes-tailings from the flotation process and the mine
pumpout. The volume of waste from the process being
discharged as a slurry to the settling pond or stored as dry
solids is directly related to the quantity of secondary
products recovered. An additional waste stream which is
unique to facility 4009 arises from the scrubbing circuit of
the low iron process which removes certain impurities from a
portion of the spodumene concentrate product, information
on the wastes from each facility is as follows:
135

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u>
LOW IRON
PROCESSING
LOW IRON
>«e*>s?ODur.'SNE
PRODUCT
FIGURE 30
SPCDUMENE MINING AND PROCESSING
(FLOTATION PROCESS)

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Facility 4001
Waste Material
Slimes
Tailings
Mine water
Facility 4009
Waste Material
Slimes S tailings
Mine water
Scrubber slurry
Water Use
Source
flotation
dewatering
mine pit
Source
flotation
mine pit
Low iron
process
kg/kkg of feed
fibs/1000 lb"
100
unknown
(intermittent, unknown)
kg/kkg of feed
(lbs/1000 lb) ~
620
568,000 1/day
(0.15 mgd) est.
95,000 1/day
(0.025 mgd) est.
At both facilities the process water recycle is 90 percent
or greater. With the exception of the above mentioned
scrubber slurry, the process waters are discharged to a
settling pond where a major part of the overflow is returned
for re-use. A breakdown of water use at each facility
follows.
Facility 4001
1. Water Usage
Process
Non-contact
cooling
Total
of ore
iaal/tonL
12,500 (3,000)
250 ( 60)
12,750 (3,060)
Water
Source
a)	Settling 95
pond overflow
b)	Mine pumpout
c)	Well
Well	100
2. water Recycled 12,100 (2,900)
Facility 4009
137

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1. Water Usage
1/kkg
of ore
(gal/ton)
Water
Source
Recycle
Process
26,900 (6,450)
a)	Settling 90
pond overflow
b)	Creek
Non-contact	1) 380 (90)
cooling
a)	Settling 90
pond overflow
b)	Creek
Municipal	0
2) 270 (60)
Boiler
40 (10)
Sanitary
190 (50)
Municipal
0
Total
27,780 (6,660)
2. Water Recycled 24,600 (5,900)
Waste Water Treatment
The treatment of the process waste streams consists of
flocculation and gravity settling. The slimes and flotation
tailings consists primarily of alkali aluminum silicates and
quartz. The separation of these wastes is made at different
points in the process. A flocculating agent is added and
the slurry is pumped to settling ponds. The solids settle
out and the major part of the overflow is returned to the
facility for re-use. The mine water which is pumped
intermittently is both discharged and recycled to the
process water circuit. An additional waste stream which is
unique to facility 4009 arises from the scrubbing circuit of
the low-iron process which removes certain impurities from
the spodumene concentrate product. This stream is currently
being impounded for future treatment prior to being
discharged into the existing facility effluent stream.
Effluents
Each facility has a single effluent stream. These
discharges consist primarily of the settling pond overflow
along with minor contributions from the mine pump-out and
miscellaneous surface runoff. For facility 4 009 the point
of measurement of the discharge also encompasses some flow
from two streams which pass through the property and serve
as an intake water source to the facility. Measurements of
these parameters in effluent and intake are as follows:
138

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Facility 1001	Facility 4009
Discharge	Intake Discharge
nis/i ~ sasZI ~
Flow-l/day (mgd) 830,000 (0.22) —	7,900,000 (2.1)
BOD
6
1.2
1.6
TDS

261
515 (461-593)


(216-288)

TSS

7.5
14
Phosphorus (as P)
0.05
0.08
0.32


(0.05-0.15)
(0. 14-0.53)
Chloride

5.8
28
Sulfate (as S)

66
63
Aluminum

1.8
4.2
Iron

0.08
0.6


(0.05-0.12)
(0.15-1. 1)
Manganese

0. 10
1.7


(0.03-0.20)
(0.4-3.4)
Silicon

8.4
14.6
Sodium

9
29
Potassium

4.9
6.0
Fluoride
0.7
0.53
2.2


(0.20-0.72)
(1.8-2.7)
Lithium

0.28
6.3


(0. 11-0.46)
(4.1-8.4)
PH

7.5-8.0
7.0-7.5
The variations in the parameters listed above are primarily
a result of changes in ore composition with resulting
process adjustment.
139

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SECTION VI
SELECTION OF POLLUTANT PARAMETERS
INTRODUCTION
The waste water constituents of pollution significance for
this segment of the mineral mining and processing industry
are based upon those parameters which have been identified
in the untreated wastes from each subcategory of this study.
The waste water constituents are further divided into those
that have been selected as pollutants of significance with
the rationale for their selection, and those that are not
deemed significant with the rationale for their rejection.
The basis for selection of the significant pollutant para-
meters was:
(1)	toxicity to terrestrial and aquatic organisms;
(2)	substances causing dissolved oxygen depletion in
streams;
(3)	soluble consitutents that result in undesirable tastes
and odors in water supplies;
(4)	substances that result in eutrophication and stimulate
undesirable algae growth;
(5)	substances that produce unsightly conditions in
receiving water; and
(6)	substances that result in sludge deposits in streams.
SIGNIFICANCE AND RATIONALE FOR SELECTION OF POLLUTION
PARAMETERS
Biochemical Oxygen Demand (BOD)
Biochemical oxygen demand (BOD) is a measure of the oxygen
consuming capacilities of organic matter. The BOD does not
in itself cause direct harm to a water system, but it does
exert an indirect effect by depressing the oxygen content of
the water. Sewage and other organic effluents during their
processes of decomposition exert a BOD, which can have a
catastrophic effect on the ecosystem by depleting the oxygen
supply, conditions are reached frequently where all of the
oxygen is used and the continuing decay process causes the
production of noxious gases such as hydrogen sulfide and
methane. Water with a high BOD indicates the presence of
decomposing organic matter and subsequent high bacterial
counts that degrade its quality and potential uses.
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Dissolved oxygen (DO) is a water quality constituent that,
in appropriate concentrations, is essential not only to keep
organisms living but also to sustain species reproduction,
vigor, and the development of populations. Organisms
undergo stress at reduced DO concentrations that make them
less competitive and able to sustain their species within
the aquatic environment. For example, reduced DO
concentrations have been shown to interfere with fish
population through delayed hatching of eggs, reduced size
and vigor of embryos, production of deformities in young,
interference with food digestion, acceleration of blood
clotting, decreased tolerance to certain toxicants, reduced
food efficiency and growth rate, and reduced maximum
sustained swimming speed. Fish food organisms are likewise
affected adversely in conditions with suppressed DO. Since
all aerobic aquatic organisms need a certain amount of
oxygen, the consequences of total lack of dissolved oxygen
due to a high BOD can kill all inhabitants of the area.
If a high BOD is present, the quality of the water is
usually visually degraded by the presence of decomposing
materials and algae blooms due to the uptake of degraded
materials that form the foodstuffs of the algal populations.
BOD was not a major contribution to pollution in this
industry and is therefore not limited.
Fluorides
As the most reactive non-metal, fluorine is never found free
in nature but as a constituent of fluorite or fluorspar,
calcium fluoride, in sedimentary rocks and also of cryolite,
sodium aluminum fluoride, in igneous rocks. Owing to their
origin only in certain types of rocks and only in a few
regions, fluorides in high concentrations are not a common
constituent of natural surface waters, but they may occur in
detrimental concentrations in ground waters.
Fluorides are used as insecticides, for disinfecting brewery
apparatus, as a flux in the manufacture of steel, for
preserving wood and mucilages, for the manufacture of glass
and enamels, in chemical industries, for water treatment,
and for other uses. Fluorides in sufficient quantity are
toxic to humans, with doses of 250 to 450 mg giving severe
symptoms or causing death.
There are numerous articles describing the effects of
fluoride-bearing waters on dental enamel of children; these
studies lead to the generalization that water containing
less than 0.9 to 1.0 mg/1 of fluoride will seldom cause
mottled enamel in children, and for adults, concentrations
less than 3 or 4 mg/1 are not likely to cause endemic
cumulative fluorosis and skeletal effects. Abundant
142

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literature is also available describing the advantages of
maintaining 0.8 to 1.5 mg/1 of fluoride ion in drinking
water to aid in the reduction of dental decay, especially
among children.
Chronic fluoride poisoning of livestock has been observed in
areas where water contained 10 to 15 mg/1 fluoride.
Concentrations of 30-50 mg/1 of fluoride in the total ration
of dairy cows is considered the upper safe limit. Fluoride
from waters apparently does not accumulate in soft tissue to
a significant degree and it is transferred to a very small
extent into the milk and to a somewhat greater degree into
eggs. Data for fresh water indicate that fluorides are
toxic to fish at concentrations higher than 1.5 mg/1.
Fluoride is found in the fluorspar, phosphate and lithium
subcategories.
Acidity and Alkalinity
Acidity and alkalinity are reciprocal terms. Acidity is
produced by substances that yield hydrogen ions upon
hydrolysis and alkalinity is produced by substances that
yield hydroxyl ions. The terms "total acidity" and "total
alkalinity" are often used to express the buffering capacity
of a solution. Acidity in natural waters is caused by
carbon dioxide, mineral acids, weakly dissociated acids, and
the salts of strong acids and weak bases. Alkalinity is
caused by strong bases and the salts of strong alkalies and
weak acids.
The term pH is a logarithmic expression of the concentration
of hydrogen ions. At a pH of 7, the hydrogen and hydroxyl
ion concentrations are essentially equal and the water is
neutral. Lower pH values indicate acidity while higher
values indicate alkalinity. The relationship between pH and
acidity and alkalinity is not necessarily linear or direct.
Waters with a pH below 6.0 are corrosive to water works
structures, distribution lines, and household plumbing
fixtures and can thus add such constituents to drinking
water as iron, copper, zinc, cadmium and lead. The hydrogen
ion concentration can affect the "taste" of the water. At a
low pH, water tastes "sour". The bactericidal effect of
chlorine is weakened as the pH increases, and it is
advantageous to keep the pH close to 7. This is very
significant for providing safe drinking water.
Extremes of pH or rapid pH changes can exert stress
conditions or kill aquatic life outright. Dead fish,
associated algal blooms, and foul stenches are aesthetic
liabilities of any waterway. Even moderate changes from
"acceptable" criteria limits of pH are deleterious to some
143

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species. The relative toxicity to aquatic life of many
materials is increased by changes in the water pH.
Metalocyanide complexes can increase a thousandfold in
toxicity with a drop of 1.5 pH units. The availability of
many nutrient substances varies with the alkalinity and
acidity. Ammonia is more lethal with a higher pH.
The lacrimal fluid of the human	eye has a pH of
approximately 7.0 and a deviation of 0.1	pH unit from the
norm may result in eye irritation	for the swimmer.
Appreciable irritation will cause severe	pain.
Total Suspended Solids
Suspended solids include both organic and inorganic
materials. The inorganic components include sand, silt, and
clay. The organic fraction includes such materials as
grease, oil, tar, animal and vegetable fats, various fibers,
sawdust, hair and various materials from sewers. These
solids may settle out rapidly and bottom deposits are often
a mixture of both organic and inorganic solids. They
adversely affect fisheries by covering the bottom of the
stream or lake with a blanket of material that destroys the
fish-food bottom fauna or the spawning ground of fish.
Deposits containing organic materials may deplete bottom
oxygen supplies and produce hydrogen sulfide, carbon
dioxide, methane, and other noxious gases.
In raw water sources for domestic use, state and regional
agencies generally specify that suspended solids in streams
shall not be present in sufficient concentration to be
objectionable or to interfere with normal treatment
processes. Suspended solids in water may interfere with
many industrial processes, and cause foaming in boilers, or
encrustations on equipment exposed to water, especially as
the temperature rises. Suspended solids are undesirable in
water for textile industries; paper and pulp; beverages;
dairy products; laundries; dyeing; photography; cooling
systems, and power facilities. Suspended particles also
serve as a transport mechanism for pesticides and other
substances which are readily sorbed into or onto clay
particles.
Solids may be suspended in water for a time, and then settle
to the bed of the stream or lake. These settleable solids
discharged with man1s wastes may be inert, slowly
biodegradable materials, or rapidly decomposable substances.
While in suspension, they increase the turbidity of the
water, reduce light penetration and impair the
photosynthetic activity of aquatic facilities.
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Solids in suspension are aesthetically displeasing. When
they settle to form sludge deposits on the stream or lake
bed, they are often much more damaging to the life in water,
and they retain the capacity to displease the senses.
Solids, when transformed to sludge deposits, may do a
variety of damaging things, including blanketing the stream
or lake bed and thereby destroying the living spaces for
those benthic organisms that would otherwise occupy the
habitat. When of an organic and therefore decomposable
nature, solids use a portion or all of the dissolved oxygen
available in the area. Organic materials also serve as a
seemingly inexhaustible food source for sludgeworms and
associated organisms.
Turbidity is principally a measure of the light absorbing
properties of suspended solids. It is frequently used as a
substitute method of quickly estimating the total suspended
solids when the concentration is relatively low. Total
suspended solids are the single most important pollutant
parameter found in this segment of the mineral mining and
processing industry.
Sulfides
Sulfides may be present in significant amounts in the waste-
water from the manufacture of rock salt and sulfur
facilities. Concentrations in the range of 1.0 to 25.0 mg/1
of sulfides may be lethal in 1 to 3 days to a variety of
fresh water fish.
Phosphates
Phosphates, reported as total phosphorus (P) , contributes to
eutrophication in receiving bodies of water.
Radiation and Radioactivity
Exposure to ionizing radiation at levels substantially above
that of general background levels can be harmful to living
organisms. Such exposure may cause adverse somatic effects
such as cancer and life shortening as well as genetic
damage. At environmental levels that may result from
releases by industries processing materials containing
natural radionuclides, the existence of such adverse effects
has not been verified. Nevertheless, it is generally agreed
that the prudent public health policy is to assume a non-
threshold health effect response to radiation exposure.
Furthermore, a linear response curve is generally assumed
which enables the statistical estimate of risk from observed
values at higher exposures to radiation through to zero
exposure.
145

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The half-life of the particular radionuclides released to
the environment by an industry is extremely important in
determining the significance of such releases. Once
released to the biosphere, radionuclides with long half-
lives can persist for hundreds and thousands of years. This
fact coupled with their possible buildup in the environment
can lead to their being a source of potential population
exposure for many hundreds of years. Therefore, in order to
minimize the potential impact of these radionuclides, they
must be excluded from the biosphere as much as possible.
Facilities and animals that incorporate radioactivity
through the biological cycle can pose a health hazard to man
thorugh the food chain. Facilities and animals, to be of
significance in the cycling of radionuclides in the aquatic
enviornment must assimilate the radionuclide, retain it, be
eaten by another organism, and be digestible. However, even
if an organism is not eaten before it dies, the radionuclide
will remain in the biosphere continuing as a potential
source of exposure.
Aquatic life may assimilate radionuclides from materials
present in the water, sediment, and biota. Humans can
assimilate radioactivity through many different pathways.
Among them are drinking contaminated water, and eating fish
and shellfish that have radionuclides incorporated in them.
Where fish or other fresh or maring products that may
accumulate radioactive materials are used as food by humans,
the concentrations of the radionuclides in the water must be
restricted to provide assurance that the total intake of
radionuclides from all sources will not exceed recommended
levels.
Radium 226
Radium 226 is a member of the uranium decay series. It has
a half-life of 1620 years. This radionuclidese is naturally
present in soils throughout the United States in
concentrations ranging from 0.15 to 2.8 picocuries per gram.
It is also naturally present in ground waters and surface
streams in varying concentrations. Radium 226 is present in
minerals in the earth*s crust. Generally, minerals contain
varying concentrations of radium 226 and its decay products
depending upon geological methods of deposition and leaching
action over the years. The human body may incorporate
radium in bone tissue in lieu of calcium. Some facilities
and animals concentrate radium which can significantly
impact the food chain.
As a result of its long half-life, radium 226 which was
present in minerals extracted from the earth may persist in
the biosphere for many years after introduction through
146

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effluents or wastes. Therefore, because of its radiological
consequences, concentrations of this radionuclide need to be
restricted to minimize potential exposure to humans.
Concentrations of this radionuclide need to be restricted to
minimize the opportunity to cause exposure to humans.
SIGNIFICANCE AND RATIONALE FOR REJECTION OF POLLUTION
PARAMETERS
A number of pollution parameters besides those selected were
considered, but had to be rejected for one or several of the
following reasons:
(1)	insufficient data on facility effluents;
(2)	not usually present in quantities sufficient to cause
water quality degradation;
(3)	treatment does not •• practicably" reduce the parameter;
and
(4)	simultaneous reduction is achieved with another
parameter which is limited.
Toxic Materials
Although arsenic, antimony, barium, boron, cadmium,
chromium, copper, cyanide ion, mercury, nickel, lead,
selenium, and tin are harmful pollutants, they were not
found to be present in quantities sufficient to cause water
quality degradation.
Dissolved Solids
The cations Al+3, Ca*2, K+ and Na+, the anion CI - and the
radical groups C03-2, N03-, NO^-, phosphates, and silicates
are commonly found in all natural water bodies. Process
water, mine water and storm runoff will accumulate
quantities of the above constituents both in the form of
suspended and dissolved solids. Limiting suspended solids
and dissolved solids, where they pose a problem, is a more
practicable approach to limiting these ions.
147

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SECTION VII
CONTROL AND TREATMENT TECHNOLOGY
INTRODUCTION
The mining and processing of minerals for the chemical and
fertilizer industries differ from the other segments of the
mineral mining industry in that their waterborne wastes
contain a wider variety of suspended solids (calcium
fluorides, phosphates, sulfur, sand, clay, and rock
particles) and dissolved solids (fluorides, sulfides,
thiosulfates, sulfites, phosphates, metal salts, acids,
alkalies, and organics).
Treatment technologies are available for reducing or
removing both suspended and undesired dissolved solids.
However, their use may be restricted by space requirements,
economics, or geographic location.
PROBLEM POLLUTANTS
Four significant waste water problem areas have been found
in these industries:
(1)	Mine water drainage containing acid, heavy metals,
fluorides and phosphates occurs more frequently in this
segment of the mineral mining industry.
(2)	The waste water from the fluorspar industry contains
soluble fluoride in addition to suspended solids.
(3)	Phosphate ore beneficiation produces extraordinarily
large quantities of slimes that have exceptionally high
water retention.
(4)	Sulfur production from on-shore salt quantities of
bleedwater brine containing up to 1,000 mg/1 of
sulfides. Both sulfides and brine content cause
treatment and/or disposal problems for the sulfur
industry.
Brief discussions of each of these problem areas are given
below.
14 9

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Mine Water Drainage
Mine drainage is encountered in a number of the chemical and
fertilizer mineral mining operations. The amount and
composition of mine water drainage differs for each
category. Most mines have only a small amount of drainage
which can be handled with little or no treatment. There
are, however, a number of exceptions:
(1)	Phosphate mines where the ore lies below the water
table. In this case the water table may be lowered by
massive pumping which drains the mine and the
surrounding area. Alternatives include either mining
below the water level or draining the mine by direct
pumping.
(2)	Salt mines often have seepage and drainage problems.
The methods of handling this drainage include pumping
the water to the surface with subsequent treatment and
disposal, to pumping the drainage directly to a nearby
aquifer.
(3)	Fluorspar mine drainage varies over a large range. The
quality of this water in terms of suspended solids and
dissolved fluoride is usually better than waste water
from associated beneficiating facilities.
(4)	Barite mines usually have small amounts of mine
drainage. At least one mine, however, has a large
drainage flow of acidic water containing dissolved heavy
metal salts. Mine water treatment is a major problem
for this operation.
Phosphate Slimes
Phosphate ore contains three major components: sand, fine
particles of mud or slime, and product phosphate rock. The
sand tailings are readily disposed as a slurry pumped to
settling areas where they settle rapidly and compactly. The
mud or slime component settles more slowly and does not form
compact solids. Currently, the only treatment and disposal
technology for these wastes is the settling pond. Ponds
serve not only as settling areas, but also as impoundments
for settled material. Due to a high level of water
retention by the slimes, large volume ponds are necessary in
this industry. Also, in order to prevent discharge of
hazardous materials in the slimes, extensive use of dikes
and dams is necessary. This treatment technology presents
problems for land reclamation.
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CONTROL PRACTICES
Corvtrol prac-tices such as selection of raw materials, good
housekeeping, minimizing leaks and spills, in-process
changes, and segregation of process waste water streams are
of limited importance in the chemical and fertilizer
minerals industries. Raw materials are fixed by the
composition of the ore available; good housekeeping and
small leaks and spills have little influence on the waste
loads; and it is rare that any non-contact water, such as
cooling water, is involved in these processes.
There are a number of areas, however, where control is very
important. These include:
(1)	waste water containment
(2)	separation and control of mine water, process water, and
rain water
(3)	monitoring of waste streams.
Containment
The majority of waste water treatment and control facilities
in the chemical and fertilizer minerals industry use one or
more settling ponds. Often the word "pond" is a euphemism
for swamp, gully, or other low spot which will collect
water, in times of heavy rainfall these "ponds" often flood
and the settled solids may be swept out. In many other
cases, the identity of the pond may be maintained during
rainfall but its function as a settling pond is
significantly impaired by the large amount of water flowing
through it. In addition to rainfall and flooding
conditions, waste containment in ponds can be troubled with
seepage through the ground around and beneath the pond,
escape through pot holes, faults and fissures below the
water surface and physical failure of pond dams and dikes.
A good example of the necessity for reliable containment has
been previously mentioned for phosphate slimes.
In most instances satisfactory pond performance can be
achieved by proper design. In instances where preliminary
laboratory tests indicate that insufficient land is
available to achieve satisfactory suspended solids removal
alternative treatment methods can be utilized: thickeners,
clarifiers, tube and lamella separators, filters,
hydrocyclones, and centrifuges.
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Separation and Control of Waste Water
In these industries waste water may be separated into three
different classifications:
(1)	Mine drainage water. Since mineral mining operations
often Involve large surface areas, the rain water that
falls on the mine or mine property surface constitutes a
major portion of the overall waste water load leaving
the property. This runoff entrains minerals, silt,
sand, clay, organic matter and other suspended solids.
(2)	Process water. This is water involved in transporting,
classifying,"washing, beneficiating, and separating ores
and other mined materials. When present in minerals
mining operations this water usually contains heavy
loads of suspended solids and possibly some dissolved
materials.
The relative amounts and compositions of the above waste
water streams differ from one mining category to another and
the separation, control and treatment techniques differ for
each.
Process water and mine drainage are normally controlled and
contained by pumping or gravity flow through pipes,
channels, ditches and ponds. Rain water runoff, on the
other hand, is often uncontrolled and may join process and
mine drainage water.
Control technology, as discussed in this report, includes
techniques and practices employed before, during, and after
the actual mining or processing operation to reduce or
eliminate adverse environmental effects resulting from the
discharge of mine or process facility waste water.
Effective pollution-control planning can reduce pollutant
contributions from active mining and processing sites and
can also minimize post-operational pollution potential.
Because pollution potential may not cease with closure of a
mine or process facility, control measures also refer to
methods practiced after an operation has terminated
production of ore or concentrated product. The presence of
pits, storage areas for spoil (non-ore material, or waste),
tailing ponds, disturbed areas, and other results or effects
of mining or processing operations necessitates integrated
plans for reclamation, stabilization, and control to return
the affected areas to a condition at least fully capable of
supporting the uses which it was capable of supporting prior
to any mining and to achieve a stability not posing any
threat of water diminution, or pollution and to minimize
potential hazards associated with closed operations.
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Mining Techniques
Mining techniques can effectively reduce amounts of
pollutants coming from a mine area by containment within the
mine area or by reducing their formation. These techniques
can be combined with careful reclamation planning and
implementation to provide maximum at-source pollution
control.
Several techniques have been implemented to reduce
environmental degradation during strip-mining operations.
Utilization of the box-cut technique in moderate- and
shallow-slope contour mining has increased recently because
more stringent environmental controls are being implemented.
A box cut is simply a contour strip mine in which a low-wall
barrier is maintained. Spoil may be piled on the low wall
side. This technique significantly reduces the amount of
water discharged from a pit area, since that water is
prevented from seeping through spoil banks. The problems of
preventing slides, spoil erosion, and resulting stream
sedimentation are still present, however.
Block-cut mining was developed to facilitate regrading,
minimize overburden handling, and contain spoil within
mining areas. In block-cut mining, contour stripping is
typically accomplished by throwing spoil from the bench onto
downslope areas. This downslope material can slump or
rapidly erode and must be moved upslope to the mine site if
contour regrading is desired. The land area affected by
contour strip mining is substantially larger than the area
from which the ores are extracted. When using block-cut
mining, only material from the first cut is deposited in
adjacent low areas. Remaining spoil is then placed in mined
portions of the bench. Spoil handling is restricted to the
actual pit area for all areas but the first cut, which
significantly reduces the area disturbed.
Pollution-control technology in underground mining is
largely restricted to at-source methods of reducing water
influx into mine workings. Infiltration from strata
surrounding the workings is the primary source of water, and
this water reacts with air and sulfide minerals within the
mines to create acid pH conditions and, thus, to increase
the potential for solubilization of metals. Underground
mines are, therefore, faced with problems of water handling
and mine-drainage treatment. Open-pit mines, on the other
hand, receive both direct rainfall and runoff contributions,
as well as infiltrated water from intercepted strata.
Infiltration in underground mines generally results from
rainfall recharge of a ground-water reservoir. Rock
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fracture zones, joints, and faults have a strong influence
on ground-water flow patterns since they can collect and
convey large volumes of water. These zones and faults can
intersect any portion of an underground mine and permit easy
access of ground water. In some mines, infiltration can
result in huge volumes of water that must be handled and
treated. Pumping can be a major part of the mining
operation in terms of equipment and expense—particularly,
in mines which do not discharge by gravity.
Water-infiltration control techniques, designed to reduce
the amount of water entering the workings, are extremely
important in underground mines located in or adjacent to
water-bearing strata. These techniques are often employed
in such mines to decrease the volume of water requiring
handling and treatment, to make the mine workable, and to
control energy costs associated with dewatering. The
techniques include pressure grouting of fissures which are
entry points for water into the mine. New polymer-based
grouting materials have been developed which should improve
the effectiveness of such grouting procedures. In severe
cases, pilot holes can be drilled ahead of actual mining
areas to determine if excessive water is likely to be
encountered. When water is encountered, a small pilot hole
can be easily filled by pressure grouting, and mining
activity may be directed toward non-water-contributing areas
in the formation. The feasibility of such control is a
function of the structure of the ore body, the type of
surrounding rock, and the characteristics of ground water in
the area.
Decreased water volume, however, does not necessarily mean
that waste water pollutant loading will also decrease. In
underground mines, oxygen, in the presence of humidity,
interacts with minerals on the mine walls and floor to
permit pollutant formation e.g., acid mine water, while
water flowing through the mine transports pollutants to the
outside. If the volume of this water is decreased but the
volume of pollutants remains unchanged, the resultant
smaller discharge will contain increased pollutant
concentrations, but approximately the same pollutant load.
Rapid pumpout of the mine can, however, reduce the contact
time and significantly reduce the formation of pollutants.
Reduction of mine discharge volume can reduce water handling
costs. In cases of acid mine drainage, for example, the
same amounts of neutralizing agents will be required because
pollutant loads will remain unchanged. The volume of mine
water to be treated, however, will be reduced significantly,
together with the size of the necessary treatment and
settling facilities. This cost reduction, along with cost
savings which can be attributed to decreased pumping volumes
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(hence, smaller pumps, lower energy requirements, and
smaller treatment facilities), makes use of water
infiltration-control techniques highly desirable.
Water entering underground mines may pass vertically through
the mine roof from rock formation above. These rock units
may have well-developed joint systems (fractures along which
no movement occurs), which tend to facilitate vertical flow.
Roof collapses can also cause widespread fracturing in over-
lying rocks, as well as joint separation far above the mine
roof. Opened joints may channel flow from overlying
aquifers (water-bearing rocks), a flooded mine above, or
even from the surface.
Fracturing of overlying strata is reduced by employing any
or all of several methods: (1) Increasing pillar size; (2)
Increasing support of the roof; (3) Limiting the number of
mine entries and reducing mine entry widths; (4) Backfilling
of the mined areas with waste material.
Surface mines are often responsible for collecting and
conveying large quantities of surface water to adjacent or
underlying underground mines. Ungraded surface mines often
collect water in open pits when no surface discharge point
is available. That water may subsequently enter the ground-
water system and then percolate into an underground mine.
The influx of water to underground mines from either active
or abandoned surface mines can be significantly reduced
through implementation of a well-designed reclamation plan.
The only actual underground mining technique developed
specifically for pollution control is preplanned flooding.
This technique is primarily one of mine design, in which a
mine is planned from its inception for post-operation
flooding or zero discharge. In drift mines and shallow
slope or shaft mines, this is generally achieved by working
the mine with the dip of the rock (inclination of the rock
to the horizontal) and pumping out the water which collects
in the shafts. Upon completion of mining activities, the
mine is allowed to flood naturally, eliminating the
possibility of acid formation caused by the contact between
sulfide minerals and oxygen. Discharges, if any, from a
flooded mine should contain a much lower pollutant
concentration. A flooded mine may also be sealed.
Surface-water Control
Pollution-control technology related to mining areas, ore-
beneficiation facilites, and waste-disposal sites is
generally designed for prevention of pollution of surface
waters (i.e., streams, impoundments, and surface runoff).
Prior planning for waste disposal is a prime control method.
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Disposal sites should be isolated from surface flows and
impoundments to prevent or minimize pollution potential. In
addition, several techniques are practiced to prevent water
pollution:
(1)	Construction of a clay or other type of liner
beneath the planned waste disposal area to prevent
infiltration of surface water (precipitation) or
water contained in the waste into the ground-water
system.
(2)	Compaction of waste material to reduce
infiltration.
(3)	Maintenance of uniformly sized refuse to enhance
good compaction (which may require additional
crushing).
(4)	Construction of a clay liner over the material to
minimize infiltration. This is usually succeeded
by placement of topsoil and seeding to establish a
vegetative cover for erosion protection and runoff
control.
(5)	Excavation of diversion ditches surrounding the
refuse disposal site to exclude surface runoff from
the area. These ditches can also be used to
collect seepage from refuse piles, with subsequent
treatment, if necessary.
Surface runoff in the immediate area of beneficiation
facilities presents another potential pollution problem.
Runoff from haul roads, areas near conveyors, and ore
storage piles is a potential source of pollutant loading to
nearby surface waters. Several current industry practices
to control this pollution are:
(1)	Construction of ditches surrounding storage areas
to divert surface runoff and collect seepage that
does occur.
(2)	Establishment of a vegetative cover of grasses in
areas of potential sheet wash and erosion to
stabilize the material, to control erosion and
sedimentation, and to improve the aesthetic aspects
of the area.
(3)	Installation of hard surfaces on haul roads,
beneath conveyors, etc., with proper slopes to
direct drainage to a sump. Collected waters may be
pumped to an existing treatment facility for
treatment.
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Another potential problem associated with construction of
tailing-pond treatment systems is the use of existing
valleys and natural drainage areas for impoundment of mine
water or process facility process waste water. The capacity
of these impoundment systems frequently is not large enough
to prevent high discharge flow rates—particularly, during
the late winter and early spring months. The use of
ditches, flumes, pipes, trench drains, and dikes will assist
in preventing runoff caused by snowmelt, rainfall, or
streams from entering impoundments. Very often, this runoff
flow is the only factor preventing attainment of zero
discharge. Diversion of natural runoff from impoundment
treatment systems, or construction of these facilities in
locations which do not obstruct natural drainage, is
therefore, desirable.
Ditches may be constructed upslope from the impoundment to
prevent water from entering it. These ditches also convey
water away and reduce the total volume of water which must
be treated. This may result in decreased treatment costs,
which could offset the costs of diversion.
Segregation or Combination of Mine and Process facility
Wastewaters	~ ~
A widely adopted control practice in the ore mining and
dressing industry is the use of mine water as a source of
process water. In many areas, this is a highly desirable
practice, because it serves as a water-conservation measure.
Waste constituents may thus be concentrated into one waste
stream for treatment. In other cases, however, this
practice results in the necessity for discharge from a
process facility-water impoundment system because, even with
recycle of part of the process water, a net positive water
balance results.
At several sites visited as part of this study, degradation
of the mine water quality is caused by combining the waste-
water streams for treatment at one location. A negative
effect results because water with low pollutant loading
serves to dilute water of higher pollutant loading. This
often results in decreased water-treatment efficiency
because concentrated waste streams can often be treated more
effectively than dilute waste streams. The mine water in
these cases may be treated by relatively simple methods;
while the volume of waste water treated in the process
facility impoundment system will be reduced, this water will
be treated with increased efficiency.
There are also locations where the use of mine water as
process water has resulted in an improvement in the ultimate
effluent. Choice of the options to segregate or combine
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waste water treatment for mines and process facilitys must
be made on an individual basis, taking into account the
character of the waste water to be treated (at both the mine
and the process facility), the water balance in the
mine/process facility system, local climate, and topography.
The ability of a particular operation to meet zero or
reduced effluent levels may be dependent upon this decision
at each location.
Regrading
Surface mining may often require removal of large amounts of
overburden to expose the ores to be exploited. Regrading
involves mass movement of material following ore extraction
to achieve a more desirable land configuration. Reasons for
regrading strip mined land are:
(1)	aesthetic improvement of land surface
(2)	returning usefulness to land
(3)	providing a suitable base for revegetation
(4)	burying pollution-forming materials, e.g. heavy
metals
(5)	reducing erosion and subsequent sedimentation
(6)	eliminating landsliding
(7)	encouraging natural drainage
(8)	eliminating ponding
(9)	eliminating hazards such as high cliffs and deep
pits
(10) controlling water pollution
Contour regrading is currently the required reclamation
technique for many of the nations*s active contour and area
surface mines. This technique involves regrading a mine to
approximate original land contour. It is generally one of
the most favored and aesthetically pleasing regrading tech-
niques because the land is returned to its approximate pre-
mined state. This technique is also favored because nearly
all spoil is placed back in the pit, eliminating
oversteepened downslope spoil banks and reducing the size of
erodable reclaimed area. Contour regrading facilitates deep
burial of pollution-forming materials and minimizes contact
time between regraded spoil and surface runoff, thereby
reducing erosion and pollution formation.
However, there are also several disadvantages to contour
regrading that must be considered. In area and contour
stripping, there may be other forms of reclamation that
provide land configurations and slopes better suited to the
intended uses of the land. This can be particularly true
with steepslope contour strips, where large, high walls and
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steep final spoil slopes limit application of contour
regrading. Mining is, therefore, frequently prohibited in
such areas, although there may be other regrading techniques
that could be effectively utilized. In addition, where
extremely thick ore bodies are mined beneath shallow
overburden, there may not be sufficient spoil material
remaining to return the land to the original contour.
There are several other reclamation techniques of varying
effectiveness which have been utilized in both active and
abandoned mines. These techniques include terrace, swale,
swallow-tail, and Georgia V-ditch, several of which are
quite similar in nature. In employing these techniques, the
upper high-wall portion is frequently left exposed or
backfilled at a steep angle, with the spoil outslope
remaining somewhat steeper than the original contour. In
all cases, a terrace of some form remains where the original
bench was located, and there are provisions for rapidly
channeling runoff from the spoil area. Such terraces may
permit more effective utilization of surface-mined land in
many cases.
Disposal of excess spoil material is frequently a problem
where contour backfilling is not practiced. However, the
same problem can also occur, although less commonly, where
contour regrading is in use. Some types of overburden rock-
particularly, tightly packed sandstones—substantially
expand in volume when they are blasted and moved. As a
result, there may be a large volume of spoil material that
cannot be returned to the pit area, even when contour
backfilling is employed. To solve this problem, head-of-
hollow fill has been used for overburden storage. The extra
overburden is placed in narrow, steep-sided hollows in
compacted layers 1.2 to 2.4 meters («* to 8 feet) thick and
graded to control surface drainage.
In this regrading and spoil storage technique, natural
ground is cleared of woody vegetation, and rock drains are
constructed where natural drains exist, except in areas
where inundation has occurred. This permits ground water
and natural percolation to leave fill areas without
saturating the fill, thereby reducing potential landslide
and erosion problems. Normally, the face of the fill is
terrace graded to minimize erosion of the steep outslope
area.
This technique of fill or spoil material deposition has been
limited to relatively narrow, steep-sided ravines that can
be adequately filled and graded. Design considerations
include the total number of acres in the watershed above a
proposed head-of-hollow fill, as well as the drainage, slope
stability, and prospective land use. Revegetation usually
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proceeds as soon as erosion and siltation protection have
been completed. This technique is avoided in areas where
under-drainage materials contain high concentrations of
pollutants, since the resultant drainage would require
treatment to meet pollution-control requirements.
Erosion Control
Although regrading is the most essential part of surface-
mine reclamation, it cannot be considered a total
reclamation technique. There are many other facets of
surface-mine reclamation that are equally important in
achieving successful reclamation. The effectivenesses of
regrading and other control techniques are interdependent.
Failure of any phase could severly reduce the effectiveness
of an entire reclamation project.
The most important auxiliary reclamation procedures employed
at regraded surface mines or refuse areas are water
diversion and erosion and runoff control. Water diversion
involves collection of water before it enters a mine area
and conveyance of that water around the mine site, as
discussed previously. This procedure decreases erosion and
pollution formation. Ditches are usually excavated upslope
from a mine site to collect and convey water. Flumes and
pipes are used to carry water down steep slopes or across
regraded areas. Riprap and dumped rock are sometimes used
to reduce water velocity in the conveyance system.
Diversion and conveyance systems are designed to accommodate
predicted water volumes and velocities. If the capacity of
a ditch is exceeded, water erodes the sides and renders the
ditch ineffective.
Water diversion is also employed as an actual part of the
mining procedure. Drainways at the bases of high walls
intercept and divert discharging ground water prior to its
contact with pollution-forming materials. In some
instances, ground water above the mine site is pumped out
before it enters the mine area, where it would become
polluted and require treatment. Soil erosion is
significantly reduced on regraded areas by controlling the
course of surface-water runoff, using interception channels
constructed on the regraded surface.
Water that reaches a mine site, such as direct rainfall, can
cause serious erosion, sedimentation, and pollution
problems. Runoff-control techniques are available to
effectively deal with this water, but these techniques may
conflict with pollution-control measures. Control of
chemical pollutants forming at a mine frequently involves
reduction of water infiltration, while runoff controls to
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prevent erosion usually increase infiltration, which can
subsequently increase pollutant formation.
There are a large number of techniques in use for
controlling runoff, with highly variable costs and degrees
of effectiveness. Mulching is sometimes used as a temporary
measure which protects the runoff surface from raindrop
impacts and reduces the velocity of surface runoff.
Velocity reduction is a critical facet of runoff control.
This is accomplished through slope reduction by terracing or
grading; revegetation; or use of flow impediments such as
dikes, contour plowing, and dumped rock. surface
stabilizers have been utilized on the surface to temporarily
reduce erodability of the material itself, but expense has
restricted use of such materials in the past.
Revegetation
Establishment of good vegetative cover on a mine area is
probably the most effective method of controlling runoff and
erosion. A critical factor in mine revegetation is the
quality of the soil or spoil material on the surface of a
regraded mine. There are several methods by which the
nature of this material has been controlled. Topsoil
segregation during stripping is mandatory in many states.
This permits topsoil to be replaced on a regraded surface
prior to revegetation. However, in many forested, steep-
sloped areas, there is little or no topsoil on the
undisturbed land surface. In such areas, overburden
material is segregated in a manner that will allow the most
toxic materials to be placed at the base of the regraded
mine, and the best spoil material is placed on the mine
surface.
Vegetative cover provides effective erosion control; contri-
butes significantly to chemical pollution control; results
in aesthetic improvement; and can return land to
agricultural, recreational, or silvicultural usefulness. A
dense ground cover stabilizes the surface (with its root
system), reduces velocity of surface runoff, helps build
humus on the surface, and can virtually eliminate erosion.
A soil profile begins to form, followed by a complete soil
ecosystem. This soil profile acts as an oxygen barrier,
reducing the amount of oxygen reaching underlying materials.
This, in turn, reduces oxidation, which is a major
contributing factor to pollutant formation.
The soil profile also tends to act as a sponge that retains
water near the surface, as opposed to the original loose
spoil (which allowed rapid infiltration). This water
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evaporates from the mine surface, cooling it and enhancing
vegetative growth. Evaporated water also bypasses toxic
materials underlying the soil, decreasing pollution
production. The vegetation itself also utilizes large
quantities of water in its life processes and transpires it
back to the atmosphere, again reducing the amount of water
reaching underlying materials.
Establishment of an adequate vegetative cover at a mine site
is dependent on a number of related factors. The regraded
surface of many spoils cannot support a good vegetative
cover without supplemental treatment. The surface texture
is often too irregular, requiring the use of raking to
remove as much rock as possible and to decrease the average
grain size of the remaining material. Materials toxic to
plant life, usually buried during regrading, generally do
not appear on or near the final graded surface. If the
surface is compacted, it is usually loosened by discing,
plowing, or roto-tilling prior to seeding in order to
enhance plant growth.
Soil supplements are often required to establish a good
vegetative cover on surface-mined lands and refuse piles,
which are generally deficient in nutrients. Mine spoils are
often acidic, and lime must be added to adjust the pH to the
tolerance range of the species to be planted. It may be
necessary to apply additional neutralizing material to
revegetated areas for some time to offset continued
pollutant generation.
Several potentially effective soil supplements are currently
undergoing research and experimentation. Flyash is a waste
product of coal-fired boilers and resembles soil with
respect to certain physical and chemical properties. Flyash
is often alkaline, contains some plant nutrients, and
possesses moisture retaining and soil-conditioning
capabilities. Its main function is that of an alkalinity
source and a soil conditioner, although it must usually be
augmented with lime and fertilizers. However, flyash can
vary drastically in quality—particularly, with respect to
pH—and may contain leachable materials capable of producing
water pollution. Future research, demonstration, and
monitoring of flyash supplements will probably develop the
potential use of such materials.
Limestone screenings are also an effective long-term neutra-
lizing agent for acidic spoils. Such spoils generally
continue to produce acidity as oxidation continues. Use of
lime for direct planting upon these surfaces is effective,
but it provides only short-term alkalinity. The lime is
usually consumed after several years, and the spoil may
return to its acidic condition. Limestone screenings are of
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larger particle size and should continue to produce
alkalinity on a decreasing scale for many years, after which
a vegetative cover should be well-established. Use of large
quantities of limestone should also add alkalinity to
receiving streams. These screenings are often cheaper than
lime, providing larger quantities of alkalinity for the same
cost. Such applications of limestone are currently being
demonstrated in several areas.
Use of digested sewage sludge as a soil supplement also has
good possibilities for replacing fertilizer and
simultaneously alleviating the problem of sludge disposal.
Sewage sludge is currently being utilized for revegetation
in strip-mined areas of Ohio. Besides supplying various
nutrients, sewage sludge can reduce acidity or alkalinity
and effectively increase soil absorption and moisture-
retention capabilities. Digested sewage sludge can be
applied in liquid or dry form and must be incorporated into
the spoil surface. Liquid sludge applications require large
holding ponds or tank trucks, from which sludge is pumped
and sprayed over the ground, allowed to dry, and disced into
the underlying material. Dry sludge application requires
dryspreading machinery and must be followed by discing.
Limestone, digested sewage sludge, and flyash are all
limited by their availabilities and chemical compositions.
Unlike commercial fertilizers, the chemical compositions of
these materials may vary greatly, depending on how and where
they are produced. Therefore, a nearby supply of these
supplements may be useless if it does not contain the
nutrients or pH adjusters that are deficient in the area of
intended application. Flyash, digested sewage sludge, and
limestone screenings are all waste products of other
processes and are, therefore, usually inexpensive. The
major expense related to utilization of any of these wastes
is the cost of transporting and applying the material to the
mine area. Application may be quite costly and must be
uniform to effect complete and even revegetation.
when such large amounts of certain chemical nutrients are
utilized, it may also be necessary to institute controls to
prevent chemical pollution of adjacent waterways. Nutrient
controls may consist of preselection of vegetation to absorb
certain chemicals, or of construction of berms and retention
basins in which runoff can be collected and sampled, after
which it can be discharged or pumped back to the spoil. The
specific soil supplements and application rates employed are
selected to provide the best possible conditions for the
vegetative species that are to be planted.
Careful consideration should be given to species selection
in surface-mine reclamation. Species are selected according
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to some land-use plan, based upon the degree of pollution
control to be achieved and the site environment. A dense
ground cover of grasses and legumes is generally planted, in
addition to tree seedlings, to rapidly check erosion and
siltation. Trees are frequently planted in areas of poor
slope stability to help control landsliding. Intended
future use of the land is an important consideration with
respect to species selection. Reclaimed surface-mined lands
are occasionally returned to high-use categories, such as
agriculture, if the land has potential for growing crops.
However, when toxic spoils are encountered, agricultural
potential is greatly reduced, and only a few species will
grow.
Environmental	conditions—particularly,	climate—are
important in species selection. Usually, species are
planted that are native to an area—particularly, species
that have been successfully established on nearby mine areas
with similar climate and spoil conditions.
Revegetation of arid and semi-arid areas involves special
consideration because of the extreme difficulty of
establishing vegetation. Lack of rainfall and effects of
surface disturbance create hostile growth conditions.
Because mining in arid regions has only recently been
initiated on a large scale, there is no standard
revegetation technology. Experimentation and demonstration
projects exploring two general revegetation techniques—
moisture retention and irrigation—are currently being
conducted to solve this problem.
Moisture retention utilizes entrapment, concentration, and
preservation of water within a soil structure to support
vegetation. This may be obtained utilizing snow fences,
mulches, pits, and other methods.
Irrigation can be achieved by pumping or by gravity, through
either pipes or ditches. This technique can be extremely
expensive, and acquisition of water rights may present a
major problem. Use of these arid-climate revegetation
techniques in conjunction with careful overburden
segregation and regrading should permit return of arid mined
areas to their natural states.
Exploration. Development. and Pilot-scale Operations
Exploration activities commonly employ drilling, blasting,
excavation, tunneling, and other techniques to discover,
locate, or define the extent of an ore body. These
activities vary from small-scale (such as a single drill
hole) to large scale (such as excavation of an open pit or
outcrop face). Such activities frequently contribute to the
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pollutant loading in waste water emanating from the site.
Since available facilities (such as power sources) and ready
accessibility of special equipment and supplies often are
limited, sophisticated treatment is often not possible. In
cases where exploration activity is being carried out, the
scale of such operations is such that primary water-quality
problems involve the presence of increased suspended-solid
loads and potentially severe pH changes. Ponds should be
provided for settling and retention of waste water, drilling
fluids, or runoff from the site. Simple, accurate field
tests for pH can be made, with subsequent pH adjustment by
addition of lime (or other neutralizing agents).
Protection of receiving waters will thus be accomplished,
with the possible additional benefits of removal of metals
from solution—either in connection with solids removal or
by precipitation from solution.
Development operations frequently are large-scale, compared
to exploration activities, because they are intended to
extend already known or currently exploited resources.
Because these operations are associated with facilities and
equipment already in existence, it is necessary to plan
development activities to minimize pollution potential, and
to use existing mine or process facility treatment and
control methods and facilities. These operations should,
therefore, be subject to limitations equivalent to existing
operations with respect to effluent treatment and control.
Pilot-scale operations often involve small to relatively
large mining and beneficiation facilities even though they
may not be currently operating at full capacity or are in
the process of development to full-scale. Planning of such
operations should be undertaken with treatment and control
of waste water in mind to ensure that effluent limitation
guidelines and standards of performance for the category or
subcategory will be met. Although total loadings from such
operations and facilites are not at the levels expected from
normal operating conditions, the compositions of wastes and
the concentrations of waste water parameters are likely to
be similar. Therefore, implementation of recommended
treatment and control technologies must be accomplished.
Mine arid Pjroce$§ facility Closure
Mine Closure (Underground). Unless well-planned and well-
designed abatement techniques are implemented, an
underground mine can be a permanent source of water
pollution.
165

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Responsibility for the prevention of any adverse
environmental impacts from the temporary or permanent
closure of a deep mine should rest solely and permanently
with the mine operator. This constitutes a substantial
burden; therefore, it behooves the operator to make use of
the best technology available for dealing with pollution
problems associated with mine closure. The two techniques
most frequently utilized in deep-mine pollution abatement
are treatment and mine sealing. Treatment technology is
well defined and is generally capable of producing
acceptable mine effluent quality. If the mine operator
chooses this course, he is faced with the prospect of costly
permanent treatment of each mine discharge.
Mine sealing is an attractive alternative to the prospects
of perpetual treatment. Mine sealing requires the mine
operator to consider barrier and ceiling-support design from
the perspectives of strength, mine safety, their ability to
withstand high water pressure, and their utility for
retarding groundwater seepage. In the case of new mines,
these considerations should be included in the mine design
to cover the eventual mine closure. In the case of existing
mines, these considerations should be evaluated for existing
mine barriers and ceiling supports, and the future mine plan
should be adjusted to include these considerations if mine
sealing is to be employed at mine closure.
Sealing eliminates the mine discharge and inundates the mine
workings, thereby reducing or terminating the production of
pollutants. However, the possibility of the failure of mine
seals or outcrop barriers increases with time as the sealed
mine workings gradually became inundated by ground water and
the hydraulic head increases. Depending upon the rate of
ground-water influx and the size of the mined area, complete
inundation of a sealed mine may require several decades.
Consequently, the maximum anticipated hydraulic head on the
mine seals may not be realized for that length of time. In
addition, seepage through, or failure of, the barrier or
mine seal could occur at any time. Therefore, the mine
operator should be required to permanently maintain the
seals, or to provide treatment in the event of seepage or
failure.
Mine Closure (Surface). The objectives of proper
reclamation management of closed surface mines and
associated workings are to (1) restore the affected lands to
a condition at least fully capable of supporting the uses
which they were capable of supporting prior to any mining,
and (2) achieve a stability which does not pose any threat
to public health, safety, or water pollution. With proper
planning and management during mining activities, it is
often possible to minimize the amount of land disturbed or
166

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excavated at any one time. In preparation for the day the
operation may cease, a reclamation schedule for restoration
of existing affected areas, as well as those which will be
affected, should be specified. The use of a planned
methodology such as this will return the workings to their
premined condition at a faster rate, as well as possibly
reduce the ultimate costs to the operator.
To accomplish the objectives of the desired reclamation
goals, it is mandatory that the surface-mine operator
regrade and revegetate the disturbed area during, or upon
completion of, mining. The final regraded surface
configuration is dependent upon the ultimate land use of the
specific site, and control practices described in this
report can be incorporated into the regrading plan to
minimize erosion and sedimentation. The operator should
establish a diverse and permanent vegetative cover and a
plant succession at least equal in extent of cover to the
natural vegetation of the area. To assure compliance with
these requirements and permanence of vegetative cover, the
operator should be held responsible for successful revege-
tation and effluent water quality for a period of five full
years after the last year of augmented seeding. In areas of
the country where the annual average precipitation is 61 cm
(26 in.) or less, the operator's assumption of
responsibility and liability should extend for a period of
ten full years after the last year of augmented seeding,
fertilization, irrigation, or effluent treatment.
Process facility Closure. As with closed mines, a
beneficiation facility's potential contributions to water
pollution do not cease upon shutdown of the facility.
Tailing ponds, waste or refuse piles, haulage areas,
workings, dumps, storage areas, and processing and shipping
areas often present serious problems with respect to
contributions to water pollution. Among the most important
are tailing ponds, waste piles, and dump areas. Failure of
tailing ponds can have catastrophic consequences, with
respect to both immediate safety and water quality.
To protect against catastrophic occurrences, tailing ponds
should be designed to accommodate, without overflow, an
abnormal storm which is observed every 25 years. Since no
waste water is contributed from the processing of ores (the
facility being closed), the ponds will gradually become
dewatered by evaporation or by percolation into the
subsurface. The structural integrity of the tailing-pond
walls should be periodically examined and, if necessary,
repairs made. Seeding and vegetation can assist in
stabilizing the walls, prevent erosion and sedimentation,
lessen the probability of structural failure, and improve
the aesthetics of the area.
167

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Refuse, waste, and -tailing piles should be recontoured and
revegetated to return the topography as near as possible to
the condition it was in before the activity. Techniques
employed in surface-mine regrading and revegetation should
be utilized. Where process facilitys are located adjacent
to mine workings, the mines can be refilled with tailings.
Care should be taken to minimize disruption of local
drainage and to ensure that erosion and sedimentation will
not result. Maintenance of such refuse or waste piles and
tailing-disposal areas should be performed for at least five
years after the last year of regrading and augmented
seeding. In areas of the country where the annual average
precipitation is 6U cm (26 in.) or less, the operator*s
assumption of responsibility should extend for a period of
ten full years after the last year of auqmented seeding,
fertilization, irrigation, or effluent treatment.
Monitoring
Since most waste water discharges from these industries
contain suspended solids as the principal pollutant, complex
water analyses are not usually required. On the other hand,
some of these industries today do little or no monitoring on
waste water discharges. In order to obtain meaningful
knowledge and control of their waste water quality, many
mines and minerals processing facilities need to institute
routine monitoring measurements of the few pertinent waste
parameters.
SUSPENDED SOLIDS REMOVAL
The treatment technologies available for removing suspended
solids from chemical and fertilizer minerals waste water are
numerous and varied, but a relatively small number are used
widely. The following shows the approximate breakdown of
usage for the various techniques:
removal technique
percent of treatment facilities
using technology	~
settling ponds (unlined)
settling ponds (lined)
chemical flocculation (usually
95-97
<1
with ponds)
thickeners and clarifiers
hydrocyclones
tube and lamella settlers
screens
filters
centrifuges
2-5
2-5
<1
<1
<1
<1
<1
168

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Settling Ponds
As shown above, the predominant treatment technique for
removal of suspended solids involves one or more settling
ponds. Settling ponds are versatile in that they perform
several functions including:
C) Solids removal. Solids settle to the bottom and the
clear~water overflow is much reduced in suspended solids
content.
(2)	Equalization and water storage capacity. The clear
supernatant water layer serves as a reservoir for reuse
or for controlled discharge.
(3)	Solid waste storage. The settled solids are provided
with long term storage.
This versatility, ease of construction and relatively low
cost, explains the wide application of settling ponds as
compared to other technologies.
The performance of these ponds depends primarily on the
settling characteristics of the solids suspended, the flow
rate through the pond and the pond size. Settling ponds can
be used over a wide range of suspended solids levels. Often
a series of ponds is used, with the first collecting the
heavy load of easily settleable material and the following
ones providing final polishing to reach a desired final
suspended level. As the ponds fill with settled solids they
can be dredged to remove these solids or left filled and new
ponds constructed. The choice often depends on whether land
for additional new ponds is available. When suspended
solids levels are low and ponds large, settled solids build
up so slowly that neither dredging nor pond abandonment is
necessary, at least not for a period of many years.
Settling ponds used in the minerals industry run the gamut
from small pits, natural depressions and swamp areas to
engineered thousand acre structures with massive retaining
dams and legislated construction design. The performance of
these ponds varies from excellent to poor, depending on
character of the suspended particles, and pond size and
conf iguration.
In general, the current experience in this industry segment
with settling ponds shows effluents ranging from 14 to
703 mg/1 of TSS. Performance data for some settling ponds
and treatment systems incorporating settling ponds found in
the sulfur, phosphate rock, fluorspar, lithium minerals,
rock salt, and salines from brine lakes subcategories are
given in Table 6.
169

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TABLE 6
Settling Pond Performance
TSS. mg/1
Plant Influent Effluent
Percent
Reduction
Treatment
Sulfur



2021
1 20
65
45.83
2022
— —.
33

2023
100
14
86.0
2024
148
290

2025
271
50
81.55
2026
324
76
76.55
Fluorspar


2000
8,633
235
97.28
2009
25,356
316
98.75
Phosphate
Rock


4003
5,620
193
96.56
4005
329
50
84.80
4015
1,684
21
95.45

2,036
39
96.26
401 7
6,500
17
99.36
4023
2,985
645
78.39
Lithium Minerals
U001 17,150
4009
4, 720
41
14
99.76
99.70
Flash strip H2S,
oxidation with
seawater
None
Spray aeration to
reduce H2S, oxi-
dation with sea-
water
Oxidation, ponds
Flue gas to
strip H2S, ponds
Oxidation, ponds
Pond
Thicke ner, ponds
Pond
Ponds
Ponds
Ponds
Flocculating
agent, thickener
Flocculating
agent, pond
Flocculating
agent, pond
Rock Salt
4011 	
4014 194
180
216
None
None
Salines from Lake Brines
5896 1,945	703
63.86
None
170

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There appear to be no correlations within a sampled
subcategory due to differences in quality of intake water,
mined product, or processing. However, over the entire
range of sampled facilities both influent and effluent
characteristics have relatively normal distributions. This
is shown in Figure 31. This figure also shows a greater
standard deviation of influent characteristics than
effluent, demonstrating the characteristic effectiveness of
ponding in reducing suspended solids from a wide range of
high concentrations to a relatively narrow range of low
concentrations.
Clarifiers and Thickeners
An alternative method of removing suspended solids is the
use of clarifiers or thickeners which are essentially tanks
with internal baffles, compartments, sweeps and other
directing and segregating mechanisms to provide efficient
concentration and removal of suspended solids in one
effluent stream and clarified liquid in the other.
Clarifiers differ from thickeners primarily in their basic
purpose. Clarifiers are used when the main purpose is to
produce a clear overflow with the solids content of the
sludge underflow being of secondary importance. Thickeners,
on the other hand, have the basic purpose of producing a
high solids underflow with the character of the clarified
overflow being of secondary importance. Thickeners are also
usually smaller in size but more massively constructed for a
given throughput.
clarifiers and thickeners have a number of distinct
advantages over ponds:
(1)	Less land space is required. Area-for-area these
devices are much more efficient in settling capacity
than ponds.
(2)	Influences of rainfall are much less than for ponds. If
desired, the clarifiers and thickeners can even be
covered.
(3)	Since the external construction of clarifiers and
thickeners consists of concrete or steel tanks ground
seepage and rain water runoff influences do not exist.
On the other hand, clarifiers and thickeners suffer some
distinct disadvantages as compared with ponds:
(1) They have more mechanical parts and maintenance.
171

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lOO.OOOr
50,000 •
10,000
5,000
K
UJ
H 1,000
_J
s
o
2E
05
CO
H-
500-
LCCflND:
o PHOSPHATE ROCK
~ SULFUR
FLUORSPAR
m LITHIUM MINERALS
A SALINES FROM BRINE LAKES
A ROCK SALT
CUMULATIVE PERCENTAGE OF PLANTS
FIGURE 31
SETTUNG POND PERFORMANCE DISTRIBUTION
OF VALUES FROM INDUSTRY SEGMENT
172

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(2)	They have only limited storage capacity for either
clarified water or settled solids.
(3)	The internal sweeps and agitators in thickeners and
clarifiers require more power and energy for operation
than ponds.
Clarifiers and thickeners are usually used when sufficient
land for ponds is not available or is very expensive.
Hydrocyclones
While hydrocyclones are widely used in the separation,
classification and recovery operations involved in minerals
processing, they are used only infrequently for waste water
treatment. Even the smallest diameter units available
(stream velocity and centrifugal separation forces both
increase as the diameter decreases) are ineffective when
particle size is less than 25-50 microns. Larger particle
sizes are relatively easy to settle by means of small ponds,
thickeners or clarifiers or other gravity principle settling
devices. It is the smaller suspended particles that are the
most difficult to remove and it is these that cannot be
removed by hydrocyclones but may be handled by ponds or
other settling technology. Also hydrocyclones are of
doubtful effectiveness when flocculating agents are used to
increase settling rates.
Hydrocyclones are used as scalping units to recover small
sand or other mineral particles in the 25 to 200 micron
range, particularly if the recovered material can be sold as
product. In this regard hydrocyclones may be considered as
converting part of the waste load to useful product as well
as providing the first step of waste water treatment. Where
land availability is a problem, a bank of hydroclones may
serve in place of a primary settling pond.
Tube and Lamella Settlers
Tube and lamella settlers require less land area than
clarifiers and thickeners. These compact units, which
increase gravity settling efficiency by means of closely
packed inclined tubes and plates, can be used for either
scalping or waste water polishing operations depending on
throughput and design.
Centrifuges
Centrifuges are not widely used for minerals mining waste
water treatment. Present industrial type centrifuges are
relatively expensive and not particularly suited for this
purpose. Future use of centrifuges will depend on
173

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regulations, land space availability and the development of
specialized units suitable for minerals mining operations.
Flocculation
Flocculating agents increase the efficiency of settling
facilities and they are of two general types: ionic and
polymeric. The ionic types such as alum, ferrous sulfate
and ferric chloride function by neutralizing the repelling
double layer ionic charges around the suspended particles
and thereby allowing the particles to attract each other and
agglomerate. Polymeric types function by forming physical
bridges from one particle to another and thereby
agglomerating the particles.
Flocculating agents are most commonly used after the larger,
more readily settled, particles (and loads) have been
removed by a settling pond, hydrocyclone or other such
scalping treatment. Agglomeration, or flocculation, can
then be achieved with less reagent and less settling load on
the polishing pond or clarifier.
Flocculation agents can be used with minor modifications and
additions to existing treatment systems, but the costs for
the flocculating chemicals are often significant. Ionic
types are used in 10 to 100 mg/1 concentrations in the waste
water while the higher priced polymeric types are effective
in the 2 to 20 mg/1 concentrations. Flocculants have been
used by several segments within the minerals industry with
varying degrees of success. The use of flocculants
particularly for the hard to settle solids is more of an art
than a science, since it is frequently necessary to try
several flocculants at varying concentrations.
Screens
Screens are widely used in minerals and mining processing
operations for separations, classifications and
beneficiations. They are similar to hydrocyclones in that
they are restricted to removing the larger (50-100 micron)
particle size suspended solids of the waste water, which can
then often be sold as useful product. Screens are not
practical for removing the smaller suspended particles.
Filtration
Filtration is accomplished by passing the waste water stream
through solids-retaining screens, cloths, or particulates
such as sand, gravel, coal or diatomaceous earth using
gravity, pressure or vacuum as the driving force.
Filtration is versatile in that it can be used to remove a
wide range of suspended particle sizes.
174

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The large volumes of many waste water streams found in
minerals mining operations require large filters. The cost
of these units and their relative complexity, compared to
settling ponds, has restricted their use to a few industry
segments committed to complex waste water treatment.
DISSOLVED MATERIAL TREATMENTS
Treatments for dissolved materials are based on either
modifying or removing the undesired materials. Modification
techniques include chemical treatments such as
neutralization and oxidation-reduction reactions. Acids,
alkaline materials, sulfides and other toxic or hazardous
materials are examples of dissolved materials modified in
this way. Most removal of dissolved solids is accomplished
by chemical precipitation. Techniques such as ion exchange,
carbon adsorption, reverse osmosis and evaporation are
rarely used in the chemical and fertilizer minerals
industry.
Chemical treatments for abatement of waterborne wastes are
common. Included in this overall category are
neutralization, pH control, oxidation-reduction reactions,
coagulations, and precipitations.
Neutralization
Some of the waste waters of this study, often including mine
drainage water, are either acidic or alkaline. Before
disposal to surface water or other medium excess acidity or
alkalinity needs to be controlled to the range of pH 6 to 9.
The most common method is to treat acidic streams with
alkaline materials such as limestone, lime, soda ash, or
sodium hydroxide. Alkaline streams are treated with acids
such as sulfuric. Whenever possible, advantage is taken of
the availability of acidic waste streams to neutralize basic
waste streams and vice versa. Neutralization often produces
suspended solids which must be removed prior to waste water
disposal.
pH Control
The control of pH may be equivalent to neutralization if the
control point is at or close to pH 7. Sometimes chemical
addition to waste streams is designed to maintain a pH level
on either the acidic or basic side for purposes of
controlling solubility.
The importance of maintaining control of pH in effluent
waste waters is especially significant in the phosphate rock
industry. Figure 32 shows the effect of pH upon the
solubility of calcium phosphate in water. In the pH range
175

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2	4	6	8	10
PH
FIGURE 32
CALCiUM PHOSPHATE SOLUBILITY AS A FUNCTION OF pH
176

-------
for waste water discharged 6.2 to 8.2, which was found in
this industry, the solubility is strongly affected by pH
changes. Over this pH range, the solubility of phosphate
(as P) changes from 52.4 to 2.6 mg/1, indicating that a
slight shift in pH can cause a marked shift in phosphate
between the dissolved and suspended solids phases. Since
suspended solids can be relatively easily removed by
physical means, the need to maintain pH as high as is
otherwise permissible is evident.
Examples of pH control being used for precipitating metallic
pollutants are:
(1)	Fe+3	+ 30H- = Fe (OH) 3
(2)	Mn+2	+ 20H = Mn(OH)2 «• 2H+ + 4e-
(3)	Zn+2	+ 20H- = Zn (OH) 2
(4)	Pb+z	+ 2 (OH)" = Pb (OH) 2
(5)	Cu+2	~ 20H- = Cu (OH) 2.
Oxidation-Reduction Reactions
The modification or destruction of many hazardous wastes is
accomplished by chemical oxidation or reduction reactions.
Hexavalent chromium is reduced to the less hazardous
trivalent form with sulfur dioxide or bisulfites. Sulfides
can be oxidized with air to relatively innocuous sulfates.
The oxidation reactions for a number of sulfur compounds
pertinent to the sulfur industry are discussed below.
Inorganic Sulfur Compounds
Inorganic sulfur compounds range from the very harmful
hydrogen sulfide to the relatively innocuous sulfate salts
such as sodium sulfate. Intermediate oxidation products
include sulfides, thiosulfates, hydrosulfites, and sulfites.
Oxidation of sulfur compounds is accomplished with air,
hydrogen peroxide, chlorine, amoung others.
O) Sulfides
Sulfides are readily oxidizable with air to thiosulfate.
Thiosulfates are less harmful than sulfides (of the order of
1000 to 1) .
4S- + 302 = 2S203=
177

-------
The reaction goes to 90-95 percent completion.
(2)	Thiosulfates
Thiosulfates are difficult to oxidize further with air (21).
They can, however, be oxidized to sulfates with powerful
oxidizing agents such as chlorine or peroxides:
S203 = ~ CI2 = 2S04=
5203	= + H202 = 2SO4=
However, the Frasch sulfur industry has experienced
oxidation of sulfides to elemental sulfur and oxidation of
thiosulfides to sulfates.
(3)	Hvdrosulfites
Hydrosulfites can also be oxidized by such oxidizing agents
and perhaps with catalyzed air oxidation:
5204	= + CI2 = 2SO4
S204 = ~ H202 = 2SO4=
(4)	Sulfites
Sulfites are readily oxidized with air to sulfates at a
90-99 percent completion level. Chlorine and peroxides are
also effective.
2 SO 3 + 02 = 2S04
Precipitations
The reaction of two soluble chemicals to produce insoluble
or precipitated products is the basis for removing many
undesired waterbome wastes. Examples include lime
treatments to precipitate sulfates, fluorides, hydroxides
and carbonates and sodium sulfide precipitations of copper,
lead and other toxic heavy metals. Precipitation reactions
can generate large suspended solids loads.
The following are examples of precipitation reactions used
for waste water treatment:
(1)	S04 = + Ca (OH) 2 = CaS04 * 20H~
(2)	2F- + ca (OH) 2 = CaF2 + 20H~
(3)	Zn+* ~ Na2C03 = ZnC03 ~ 2Na*
178

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Sulfur Production
Salt dome sulfur producers have large quantities of bleed-
water to treat and dispose of. This presents two problems:
removal of sulfides and disposal of the remaining brine.
Since there is currently no practical or economical means of
removing the salt from the brine, it must be disposed of
either in brackish or salt water, or impounded and
discharged intermittently during specified times.
Removal of sulfides prior to discharge of the brine is also
a major treatment problem. There are two types of
bleedwater treatment facilities found in this industry for
removal of sulfides. Examples of each are given in Figures
33 and 34.
In treatment type 1 the bleedwater is air lifted to a small
settling basin and then sent to a mixing zone where
sulfurous acid and deposition inhibitor are added. The
bleedwater is then sent to packed towers for removal of
hydrogen sulfide. In the packed towers the bleedwater flows
countercurrent to cooled boiler flue gas. The treated
bleedwater is then aerated and sent to a series of settling
and clarification ponds prior to discharge. This method is
effective for removal of sulfides and reduction of BOD in
the bleedwater.
In treatment type 2 the bleedwater is mixed with sulfurous
acid which is generated by burning liquid sulfur or from
hydrogen sulfide originating from the bleedwater. In this
process the soluble sulfides in the bleedwater are converted
to elemental sulfur and oxidized sulfur products in a series
of reaction vessels. Excess acid is then neutralized with
lime. The insoluble sulfur is removed by sedimentation, and
the treated effluent is then sent to a series of basins
prior to discharge. This method is very effective for
removal of sulfides, but does not reduce BOD in the
bleedwater to acceptable limits.
At the one off-shore salt dome sulfur facility currently
operating, the bleedwater is discharged without treatment.
The treatment technologies used by on-shore salt dome
facilities, ponding and bleedwater treatment facilities are
not considered feasible here due to non-availability of land
and space restrictions on a platform.
179

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SULFUROUS	FLUE GAS	FLUE GAS
ACID	TO STACK	TO STACK
TO PROCESS
FOR MINE WATER
FiGURa 33
BLEEDVOTER TREATING PLANT
TYPE I

-------
WATER
WATER
I
V?
8LEEC WATER-©»
THiCKHNER
SLUDGE
TANK
IT
SETTLING
BASINS
FIGURE 34
BLEEDWATER TREATING PLANT
TYPE 2
WASTE WATER
DISCHARGE

-------
SUMMARY OF TREATMENT TECHNOLOGY APPLICATIONS, LIMITATIONS
AND RELIABILITY
Table 7 summarizes comments on the various treatment
technologies as they are utilized for the minerals and
mining industry.
Estimates of the efficiency with which the treatments remove
suspended or dissolved solids from waste water, given in the
table need to be interpreted in the following context.
These values will obviously not be valid for all
circumstances, concentrations or materials, but they should
provide a general guideline for treatment performance
capabilities. Several comments may be made concerning the
values:
(1)	At high concentrations and optimum conditions, all
treatments can achieve 99 percent or better removal of
the desired material;
(2)	At low concentrations, the removal efficiency drops off.
(3)	Minimum concentration ranges achievable will not hold in
every case. For example, pond settling of some
suspended solids might not achieve less than the
100 mg/1 level. This is not typical, however, since
many such pond settling treatments can achieve 10 to
20 mg/1 without difficulty. Failure to achieve the
minimum concentration levels listed usually means that
either the wrong treatment methods have been selected or
that an additional treatment step is necessary (such as
a second pond or polish filtration).
PRETREATMENT TECHNOLOGY
Chemical and fertilizer mineral mining operations are
usually conducted in relatively isolated regions where there
is no access to publicly owned waste water treatment
facilities. In areas where publicly owned facilities could
be used, pretreatment would often be required to reduce the
heavy suspended solids load.
In the instances where dissolved materials are serious, pH
control and some reduction of hazardous constituents such as
fluorides, sulfides, and heavy metals would be required.
Lime treatment will usually be sufficient for reductions of
fluorides and heavy metals. Sulfides would require air
oxidation or other chemical treatment.
182

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Table 7. Summary of Technology, Applications, Limitations and'Reliability
Woste
Wdfr
lifotr.eftl
FlOC'SS
Application
fiTccn!
Solids
f-rnvvc>1
l*pcd'o-
cy clones
"fccrrovol c»f !oig«r
pjiticlc sizes
50-99
-
-
rccdy
ovoiloble
3-12
opprox.
10' x 10*
smoll
sensitive
smoll
small

(4) lube end
lofr.rila
Settles
R»mjvol ©f irtriHi-r
porticlc tiicv
90-99
--
-
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3-12
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fccmovo! of 1at9er
j^ortictf il/ev
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--
"
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3-12
opptox.
10' x 10'
nominal
smoll
small
small

(6) fiotcwy
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/•'•oinly Cor sludges
pikI o.'J-cr
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sfrou.'it*
90-99
5-1000
5-30
reodily
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3-12
C|mincjl
sensitive
small
noniinol

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c("icton
ror»Q»
90-99
10-100
5-30
reodily
ovoJIoble
3-6
opprox.
10* x 10'
smoll
sensitive
smoll
smo'l

(9) Cottcldjje
o»>d Ceridlc
Filters
f.'ai'Jy fo» yolid*
irn ion; of
vuip<-«vdrd solids
50- 97
MO
2-10
rco'J'ily
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1-3
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10' * 10'
smoll
sensitive
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smoll

(10) Sn.vfc.d
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f*.*
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50-99
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3-6
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10' x *0'
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Dissolved
SoJHs
(1) N-i.r« /I-
7(i'ir"i t-r.i
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94 it'?.
'y:-7t
P-/0
0-13
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ovol^ilV
3-6
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m'tt-or
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s-nrtll
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183

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NON-WATER QUALITY ENVIRONMENTAL ASPECTS, INCLUDING ENERGY
REQUIREMENTS
The effects of -these treatment and control technologies on
noise pollution and thermal pollution are usually small and
not of any significance. Some impact on air quality occurs
with sulfide wastes generated in sulfur production.
However, the isolated locations of sulfur facilities and
selection of treatment is usually sufficient to eliminate
any problem. There is also radiation from phosphate ores
and wastes. The concentration of radionuclides is low in
materials involved with phosphate mining and beneficiating
operations. Nevertheless, significant quantities of
radionuclides may be stored or redistributed, because of the
large volumes of slimes tailings and other solid wastes.
Large amounts of solid waste in the form of both solids and
sludges are formed as a result of all suspended solids
operations as well as chemical treatments for neutralization
and precipitations. Easy-to-handle, relatively dry solids
are usually left in settling ponds or dredged out
periodically and dumped onto the land. Since mineral mining
properties are usually large, space for such dumping is
often available. Sludges and difficultly settled solids are
most often left in the settling pond, for example, phosphate
slimes, but may in some instances be landfilled.
For those waste materials considered to be non-hazardous
where land disposal is the choice for disposal, practices
similar to proper sanitary landfill technology may be
followed. The principles set forth in the EPA's Land
Disposal of Solid Wastes Guidelines (CFR Title 40, Chapter
1; Part 241) may be used as guidance for acceptable land
disposal techniques.
For those waste materials considered to be hazardous,
disposal will require special precautions. In order to
ensure long-term protection of public health and the
environment, special preparation and pretreatment may be
required prior to disposal. If land disposal is to be
practiced, these sites must not allow movement of pollutants
such as fluoride and radium-226 to either ground or surface
water. Sites should be selected that have natural soil and
geological conditions to prevent such contamination or, if
such conditions do not exist, artificial means (e.g.,
liners) must be provided to ensure long-term protection of
the environment from hazardous materials. Where
appropriate, the location of solid hazardous materials
disposal sites should be permanently recorded in the
appropriate office of the legal jurisdiction in which the
site is located.
184

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In summary, the solid wastes and sludges from the chemical
and fertilizer minerals mining industry waste water
treatments are very large in quantity, but the industry,
having sufficient space and earth-moving capabilities,
manages it with greater ease than could most other
industries.
For the best practicable control technology currently
available the added annual energy requirements are estimated
to be 9 x 10* 0 kcal. This would increase the present energy
use for control in this industry by about six percent. Over
90 percent of the added energy requirements is attributable
to two subcategories, phosphate rock (flotation) and sulfur
(on-shore salt dome) .
185

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SECTION VIII
COST, ENERGY, WASTE REDUCTION BENEFITS AND NON-WATER ASPECTS
OF TREATMENT AND CONTROL TECHNOLOGIES
SUMMARY
The chemical and fertilizer industries segment of the
mineral mining and processing industry contains several
subcategories with large waste water treatment capital
investments and operating costs. These large costs result
from large quantities of waste water or large quantities of
solid waste.
Waste treatment costs in barite mining stem mainly from the
large volumes of solid wastes generated. Often
93-97 percent of the ore is gangue wastes, much of which is
stored in settling ponds.
Both factors strongly affect the treatment costs of wastes
from phosphate rock mining. Trona ore and borate mining
waste treatment costs are high due to the use of large
evaporation ponds for waste water disposal. In both cases
percolation and seepage problems materially increase the
overall investment costs.
Large quantities of waste water are responsible for large
treatment costs in sulfur extraction. Sulfides in
bleedwater require heavy treatment chemical costs or large
ponds for oxidation by aeration.
The wastes from mineral mining ore beneficiation steps are
closely related to the ore composition and therefore
treatment costs in these industries have an additional
source of variance not experienced in other industries
having greater control of raw material quality.
In general, facility size and age have little influence on
the type of waste effluent. The amounts and costs for their
treatment and disposal are readily scaled from facility size
and are not greatly affected by facility age.
Geographical location is important. Mines and processing
facilities located in dry western areas rarely require major
waste water treatment or have subsequent disposal problems.
Terrain and land availability are also significant factors
affecting treatment technology and costs. Lack of
sufficient flat space for settling ponds often forces
187

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utilization of mechanical thickeners, clarifiers, or
settlers. On the other hand, advantage is often taken of
valleys, hills, swamps, gullies and other natural
configurations to provide low cost pond and solid waste
disposal facilities. Permeability of the terrain influences
greatly the cost of leak-proof treatment ponds.
In view of the large number of mines and beneficiation
facilities and the significant variables listed above, costs
have been developed for representative mines and processing
facilities rather than specific exemplary facilities that
may have advantageous geographical, terrain or ore
composition.
A summary of cost and energy information for the present
level of waste water treatment technology for this segment
is given in Table 8. Present capital investment for waste
water treatment in the minerals for the chemical and
fertilizer industries segment is estimated at $183,000,000.
COST REFERENCES AND RATIONALE
Cost information contained in this report was assembled
directly from industry, from waste treatment and disposal
contractors, engineering firms, equipment suppliers,
government sources, and published literature. Whenever
possible, costs are taken from actual installations,
engineering estimates for projected facilities as supplied
by contributing companies, or from waste treatment and
disposal contractors quoted prices. In the absence of such
information, cost estimates have been developed insofar as
possible from facility-supplied costs for similar waste
treatments and disposal for o-ther facilities or industries.
Interest Costs and Equity Financing Charges
Capital investment estimates for this study have been based
on 10 percent cost of capital, representing a composite
number for interest paid or return on investment required.
Time Basis for Costs
All cost estimates are based on August 1972 prices and when
necessary have been adjusted to this basis using the
chemical engineering facility cost index.
Useful Service Life
The useful service life of treatment and disposal equipment
varies depending on the nature of the equipment and process
involved, its usage pattern, maintenance care and numerous
other factors. Individual companies may apply service lives
188

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TABLE 8
CAPITAL INVESTMENTS AND ENERGY CONSUMPTION OF
PRESENT WASTEWATER TREATMENT FACILITIES
Total Annual

Capital Spent
Present Energy
Costs ($/kkg
Subcategory
(Dollars)
Use (Kcal x 10 )
produced)
Barife
11,400,000
137,000
2.5
Fluorspar
1,250,000
12,800
1.9
Borax
2,500,000
7,500
0.44
Potash
1,150,000
5,300
0.32
Trona Ore Mining



and Refining
11,000,000
75,000
0.54
Phosphate Rock



(Eastern)
120,000,000
938,000
0.73
Phosphate Rock



(Western)
18,500,000
278,000
0.54
Rock Salt
200,000
9,700
0.01
Sulfur (Anhydrite)
1,375,000
19,000
0.83
Sulfur (on-shore



Salt Doms)
14,000,000
25,000
0.95
Mineral Pigments
<50,000
<1,000
1.08
Lithium Minerals
1,200,000
6,200
6.2
Sodium Sulfate
<50,000
<1,000
0.01
TOTAL
183,000,000
1,500,000

189

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based on their actual experience for internal amortization.
Internal Revenue Service provides guidelines for tax
purposes which are intended to approximate average
experience.
Based on discussions with industry and condensed IRS guide-
line information, the following useful service life values
have been used:
(1)	General process equipment	10 years
(2)	Ponds, lined and unlined	20 years
(3)	Trucks, bulldozers, loaders
and other such materials
handling and transporting
equipment	5 years
Depreciation
The economic value of treatment and disposal equipment and
facilities decreases over its service life. At the end of
the useful life, it is usually assumed that the salvage or
recovery value becomes zero. For IRS tax purposes or
internal depreciation provisions, straight line, or
accelerated write-off schedules may be used. Straight line
depreciation was used solely in this report.
Capital Costs
Capital costs are defined as all front-end out-of-pocket
expenditures for providing treatment/disposal facilities.
These costs include costs for research and development
necessary to establish the process, land costs when
applicable, equipment, construction and installation,
buildings, services, engineering, special start-up costs and
contractor profits and contingencies.
Annual Capital Costs
Most if not all of the capital costs are accrued during the
year or two prior to actual use of the facility. This
present worth sum can be converted to equivalent uniform
annual disbursements by utilizing the Capital Recovery
Factor Method;
190

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Uniform Annual Disbursement = P i	(Hi) nth power
(1 + i)nth power - 1
Where P = present value (capital expenditure), i =
interest rate, %/100, n = useful life in years
The capital recovery factor equation above may be
rewritten as:
Uniform Annual Disbursement = P(CR - i% - n)
Where (CR - iX - n) is the*Capital Recovery Factor for
i% interest taken over Mn" years useful life.
Land Costs
Land-destined solid wastes require removal of land from
other economic use. The amount of land so tied up will
depend on the treatment/disposal method employed and the
amount of wastes involved. Although land is non-depreciable
according to IRS regulations, there are numerous instances
where the market value of the land for land-destined wastes
has been significantly reduced permanently, or actually
becomes unsuitable for future use due to the nature of the
stored waste. The general criteria applied to costing land
are as follows:
(1)	If land requirements for on-site treatment/disposal are
not significant, no cost allowance is applied.
(2)	Where on-site land requirements are significant and the
storage or disposal of wastes does not affect the
ultimate market value of the land, cost estimates
include only interest on invested money.
(3)	For significant on-site land requirements where the
ultimate market value and/or availability of the land
has been seriously reduced, cost estimates include both
capital depreciation and interest on invested money.
(4)	Off-site treatment/disposal land requirements and costs
are not considered directly. It is assumed that land
costs are included in the overall contractors fees
along with its other expenses and profit.
(5)	In view of the extreme variability of land costs,
adjustments have been made for individual industry
situations. In general, isolated, plentiful land has
been costed at $2,470/hectare ($1,000/acre).
Operating Expenses
Annual costs of operating the treatment/disposal facilities
include labor, supervision, materials, maintenance, taxes,
insurance and power and energy. Operating costs combined
with annualized capital costs give the total costs for
191

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treatment and disposal operations. No interest cost was
included for operating (working) capital. Since working
capital might be assumed to be one sixth to one third of
annual operating costs (excluding depreciation), about
1-2 percent of total operating costs might be involved.
This is considered to be well within the accuracy of the
estimates.
Rationale for Representative Facilities
All facility costs are estimated for representative
facilities rather than for any actual facility.
Representative facilities are defined to have a size and age
agreed upon by a substantial fraction of the manufacturers
in the subcategory producing the given mineral, or, in the
absence of such a consensus, the arithmetic average of
production size and age for all facilities.
Location is selected to represent the industry as closely as
possibly. For instance, if all facilities are in
northeastern U.S., typical location is noted as
"northeastern states". If locations are widely scattered
around the U.S., typical location would be not specified
geographically.
It should be noted that the unit costs to treat and dispose
of hazardous wastes at any given facility may be
considerably higher or lower than the representative
facility because of individual circumstances.
Definition of Levels of Treatment and Control
Costs are developed for various types and levels of
technology:
Minimum (or basic level). That level of technology which is
equalled or exceeded by most or all of the involved
facilities. Usually money for this treatment level has
already been spent (in the case of capital investment) or is
being spent (in the case of operating and overall costs).
B.C.D.E	Levels - Successively greater degrees of treatment
with respect~to critical pollutant parameters. Two or more
alternative treatments are developed when applicable.
Rationale for Pollutant Considerations
(1) All non-contact cooling water is exempted from treatment
(and treatment costs) provided that it is not
contaminated by process water and no harmful pollutants
are introduced.
192

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(2) Water treatment, cooling tower and boiler blowdown
discharges are not treated provided they are not
contaminated by process water and contain no harmful
pollutants.
(3)	Removal of dissolved solids, other than harmful
pollutants, is not included.
(4)	Mine drainage treatments and costs are generally
considered separately from process water treatment and
costs. Mine drainage costs are estimated for all
mineral categories for which such costs are a
significant factor.
(5)	All solid waste disposal costs are included as part of
the cost development.
Cost Variances
The effects of age, location, and size on costs for
treatment and control have been considered and are detailed
in subsequent sections for each specific subcategory.
INDUSTRY STATISTICS
Below are summarized the estimated 1972 selling prices for
the individual minerals of this report. These values were
taken from minerals industry yearbooks and Bureau of Census
publication.
mineral
Ł/!sfrg- tosl
barite	18.10	(16.43)
fluorspar	76.07	(69.00)
borates	82.96	(75.25)
potash (K20 equiv.)	37.49	(34.00)
natural soda ash	24.55	(22.27)
sodium sulfate	17.93	(16.26)
phosphate rock	5.62	(5.10)
rock salt	11.71	(10.62)
sulfur (Frasch)	18.79	(17.04)
mineral pigments	88.20	(80.00)
lithium minerals	withheld
193

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INDIVIDUAL MINERAL WASTEWATER TREATMENT AND DISPOSAL COSTS
BARITE
Of the twenty-seven known significant U.S. facilities
producing barite ore or ground barite, nine facilities use
dry grinding operations, fourteen use log washing and
jigging methods to prepare the ore for grinding, and four
use froth flotation techniques.
DRY GRINDING OPERATION
There is no water used in dry grinding facilities, therefore
there is no waste water, waste water treatment or treatment
costs.
WASHING OPERATIONS
The ratio of barite product to wastes at the various
facility vary greatly with ore quality, but in all cases
there is a large amount of solid wastes for disposal. For
several of the facilities in this subcategory only about 3
to 7 percent by weight of the ore is product. The remainder
consists of rock and gravel, which are separated and
recovered at the facility, and mud and clay tailings, which
are sent as slurry to large settling and storage ponds.
In Missouri, where most of the washing operations are
located, tailings ponds are commonly constructed by damming
deep valleys. It is customary in log washing operations to
build the initial pond by conventional earthmoving methods
before the facility opens so that process water can be
recycled. Afterwards the rock and gravel gangue are used by
the facility to build up the dam on dikes to increase the
pond capacity. This procedure provides a use for the gangue
and also provides for storage of more clay and mud tailings.
The clay and mud are used to seal the rock and gravel
additions.
All facilities totally recycle process water except during
periods of heavy rainfall when intermittent discharges
occur. During these times of heavy rainfall, Missouri
washing facilities experience varying amounts and
frequencies of discharge depending on pond design and
surrounding terrain.
A washing facility located in Nevada also uses tailings
ponds with total recycle of waste water and no discharge at
any time. The dry climate and the scarcity of water are the
factors determining the feasibility of such operation.
194

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In Table 9 are estimated costs for total recycle with
discharge only in times of heavy rainfall and no treatment
on discharged water, total recycle with discharge only in
times of heavy rainfall and treatment of all discharged
water, and total recycle with no discharge of process water
any time.
Operations in dry climates (e.g. Nevada) would be expected
to have treatment costs similar to Level A, even at no
discharge level.
All facilities are currently at Level A or C. some
facilities use Level B treatment partially. The necessity
and extent of such treatment depends on quality of water
presently discharged. Level C is not achievable in
unfavorable terrain. With favorable local terrain zero
discharge of process water is achievable.
Cost Variance
Age. Known ages range from less than 1 to 19 years. Age
was not found to be a significant factor in cost variance.
Location. Both geographical location and local terrain are
significant factors in treatment costs. Western operations
in dry climates can achieve no discharge at all times at a
cost significantly below eastern operations, costs vary
significantly with local watersheds, elevations, and
availability of suitable terrain for pond construction.
size. Nine facilities in this subcategory have production
rates ranging from 11,000 to 182,000 kkg/yr (12,100 to
200,000 tons/yr). The representative facility is
18,000 kkg/yr (20,000 tons/yr). Eight of the nine
facilities have less than 30,000 kkg/yr production
(33,000 tons/yr). The single large facility in this
subcategory that was investigated is the western facility
for which costs have been discussed earlier in this section.
For the eight eastern facilities, the cost variance of size
over this range is estimated to be 0.9 exponential function
for capital and its related annual costs, and directly
proportional for operating costs other than taxes, insurance
and capital recovery.
195

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TABI.E 9
COST	FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY	Barite (washing operations)
PLANT SIZE 18'000	 METRIC TONS PER YEAR -OF Barite
PLANT AGE " YEARS PLANT LOCATION Missouri or Nevada

LEVEL
A
(MIN)
B
C
D
E
INVESTED CAPITAL COSTS!
180,000
260,000
265,000


TOTAL
ANNUAL CAPITAL RECOVERY
21,150
30,500
31 ,100


OPERATING AND MAINTENANCE
costs:
10,000
16,400
13,600


ANNUAL 0 C, M (EXCLUDING
POWER AMD ENERGY)
ANNUAL ENERGY AK'D POWER
10,000
10,000
11,000


TOTAL ANNUAL COSTS
41,150
56,900
55,700


COST/METRIC TON BorIte
2.26
3.13
3.06


WASTE LOAD PARAMETERS
(mg/ liter)
RAW
WASTE
LOAD
15-327*
25*
0


Suspsn.-J-od solids

Iron

0.04-8.4*
1.0*
0


Lead

3.03-2.0*
0.1*
0


pH

6-9*
6-9*
*
















*only discharged during peripo's of heavy rainfall
A. Complete recycle except in times of heavy rainfall
B . A plus treatment of all discharged water with lime and flocculants
C. Complete recycle - r.o discharge at all times (ability to achieve this level
depends on local terrain - not all plants are capable of attaining zero discharge)
196

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Cost Basis For Table 9
Capital Costs
Pond cost, $/hectare ($/acre)
(a)	tailings ponds:
(b)	clarification ponds:
12,350 (5,000)
7,400	(3,000)
Pond areas, hectares (acres)
(a)	tailings ponds:
(b)	clarification ponds:
8.1 (20)
8.1 (20)
Pumps and pipes: $50,000
Operating and Maintenance Costs
Power unit cost:
Pond maintenance:
Pump and piping maintenance:
Taxes and insurance:
Plocculants:
Lime:
$100/HP-yr
2% of pond investment
6% of non-pond investment
2% of total investment
$2. 20/kg ($ 1.00/lb)
$22/kkg ($20/ton)
FLOTATION OPERATIONS
Flotation is used on either beneficiated low grade ore or
high-grade ore which is relatively free of sands, clays, and
rocks. Therefore, they produce significantly less solid
wastes (tailings) than washing operations, and consequently
less cost for waste treatment.
Wastewater treatment is similar to that previously described
for washing operations: pond settling and storage of
tailings followed by recycle. of the three facilities
investigated in this category two are in the east and one in
the west. The western facility achieves no discharge; the
two eastern facilities do not.
Costs for waste water treatment for the barite flotation
process are given in Table 10. Level A is currently
achieved in the Nevada facility. Levels B and C represent
technology used by present eastern operations. Level D is
for projected no discharge at eastern operations. At
eastern operations ability and costs to achieve no discharge
depend on local terrain. Costs developed are for cases
where favorable terrain makes achievement of no discharge
possible.
197

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TABLE 10
FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
Barite (flotation)
70*000	 METRIC TONS PER YEAR OF Barite
YEARS PLANT LOCATION Missouri, Nevada, Georgia

LEVEL"
A
(MIN)
I B \
(mm)
C
D
E
INVESTED CAPITAL COSTS:
150,000
200,000
250,000
310,000

TOTAL
ANNUAL CAPITAL RECOVERY
17,600
23,480
31,600
36,400

OPERATING AND MAINTENANCE
costs:
6,000
7,000
12,000
11,400

ANNUAL 0 V, M (EXCLUDING
POWER AMD ENERGY)
ANNUAL ENERGY AND POWER
10,000
15,000
15,000
15,000

TOTAL ANNUAL COSTS
33,600
45,480
58,600
62,800

COST/METRIC TON Barite
0.49
0.67
0.86
0.92


WASTE LOAD PARAMETERS
(mg/liter)
RAW
WASTE
LOAD
0
3-250
25
0

Suspended Solids
:50,000
PH
-
mm
6-9
6-9
-





























level description:
X". Pond settling of solids plus recycle of water to process; no discharge (western operation)
B.	Pond settling of solids plus recycle of water to process; intermittent discharge; no chemical
treatment for discharged water
C.	B plus chemical treatment with lime arid/or flocculating agent to adjust pH and reduce
suspended solids
D.	B plus additional pond capacity for total impoundment (requires favorable local terrain)
198
COST
SUBCATEGORY_
PLANT SIZE	
PLANT AGE 33

-------
Cost Variance
Age. Ages for the three facilities ranged from 10 to
58 years. Age was not found to be a significant cost
variance factor.
Location. Both geographical location and local terrain are
significant cost variance factors. Western operations are
able to achieve no discharge at treatment costs below those
for intermittent discharge from eastern facilities. No
known eastern facility currently achieves no discharge.
Size. The flotation facilities range from 33,600 to
91,000 kkg/yr	(37,000 to 100,000 tons/yr).	The
representative facility is 70,000 kkg/yr (77,000 tons/yr).
Treatment costs are essentially proportional to size in this
range.
Cost Basis For Table 10
Capital Costs
Tailings pond cost, $/hectare ($/acre)
7,U00	(3,000)
Pond area, hectares (acres) :	20	(50)
Pumps and piping:	$50,000
Chemical treatment facilities: $50,000
Operating and Maintenance Costs
Pond maintenance:	2% of pond investment
Taxes and insurance:	2% of total investment
Power - $100/HP-yr
Treatment Chemicals
Lime:	$22/kkg ($20/ton)
Flocculating agent:	$2.20/kg ($1/lb)
Mine Drainage
The mining of barite is a dry operation and the only water
normally involved is from pit or mine drainage resulting
from rainfall and/or ground seepage. Most mines do not have
any discharge. Rainwater in open pits is usually allowed to
evaporate. One known mine, however, has over
1.9 x 10* 1/day (0.5 mgd) of acidic ground seepage and
rainwater runoff. Lime neutralization and pond settling of
suspended solids of this mine drainage costs an approximate
$2 per kkg of barite produced ($1.8/ton). Most of this cost
is for lime and flocculating agents.
199

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FLUORSPAR
Beneficiation of mined fluorspar ore is accomplished by
heavy media separations and/or flotation operations.
Although these technologies are used separately in some
instances, generally beneficiation facilities employ both
techniques.
HEAVY MEDIA SEPARATIONS
The primary purpose of heavy media separations is to provide
an upgraded and preconcentrated feed for flotation
facilities. Five of the six heavy media operations have no
waste water discharge. The sixth facility uses a pond to
remove suspended solids then discharges to surface water.
Wastewater treatment costs are given in Table 11. Level A
technology is achieved by all facilities. Level B is
currently achieved by 5 of the 6.
Cost Variance
Age. Ages for this subcategory range from 1 to 30 years.
Age was not found to be a significant factor in cost
variance.
Location. Facilities are located in the Illinois-Kentucky
area and southwestern U.S. There are facilities with no
process effluents in both locations. Location is not a
significant factor in cost variance.
Size. The facilities having heavy media facilities range
from 5,900 to 81,800 kkg/yr (6,500 to 90,000 tons/yr)
production. The representative facility is 40,000 kkg/yr
(45,000 tons/yr). Since thickeners are the major capital
investment, capital costs are estimated to be
0.7 exponential function with size. Operating costs other
than taxes, insurance and capital recovery are estimated to
be directly proportional to size.
Cost Basis for Table 11
Capital Costs
Pond cost, {/hectare ($/acre):
Pond size, hectares (acres) :
Pumps and piping costs:
Thickeners:
7,400	(3,000)
4	(10)
$20,000
$50,000
200

-------
TABLE IT
COST
UBCATE60RY
PLANT SIZE
FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
Fluorspar (heavy media)
40,000
PLANT AGE
YEARS
METRIC TONS PER YEAR /OF fluorsPar
Midwest
PLANT LOCATION

LEVEL
A
(MIN)
B
C
D
E
INVESTED CAPITAL COSTS:
50,000
70,000



TOTAL
ANNUAL CAPITA!. RECOVERY
5,850
8,200



OPERATING AND MAINTENANCE
costs:
7,050
8,250



ANNUAL O 0, M (EXCLUDING
POWER AND ENERGY)
ANNUAL ENERGY AND POWER
2,500
5,000



TOTAL ANNUAL COSTS
15,400
21,450



COST/ME TRIG TON fluorspar
0.38
0.52



WASTE LOAD PARAMETERS
(ka/mctric Ion of fluorspar )
RAW
WASTE
LOAD
0.13
0



Suspended solids
340
Dissolved Fluoride
0.04
0.04
0



Lead
-
0.0002
0



Zinc
-
0.0012
0



PH
-
6-9
0










i-tiva. description:
A.	Spiral classifier followed by small pond with discharge
B.	Thickener plus total recycle
201

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Operating and Maintenance Costs
Pond maintenance:	2% of pond investment
Pumps and piping maintenance:	6% of investment
Pond cleaning:	15,000 ton/yr 3 $.35/ton
Power: $100/HP-yr
FLOTATION SEPARATIONS
Wastewater from flotation processes are more difficult and
costly to treat and dispose of than those from heavy media
separation. The bulk of the solid wastes from the ore are
discharged from the flotation process. Flotation chemicals
probably interfere with settling of suspended solids and
fluoride contents are higher than in the heavy media
process.
Cost estimates for waste water treatment from a
representative flotation facility are given in Table 12.
Level A is typical of Kentucky-Illinois area waste water
treatment. Level B represents costs for planned future
treatment for these operations. Level C represents treatment
technology used for municipal water, but not currently used
for any fluorspar waste water.
Cost Variances
Age. In the fluorspar flotation category facility ages
range from 1 to 35 years. Age has not been found to be a
significant factor in cost variance of treatment options.
Location. Both geographical location and local terrain are
significant cost variance factors. Dry climate western
operations can achieve no discharge at lower costs than
midwestern operations can meet normal suspended solids
levels in their discharges.
Size. Facility sizes range from 13,600 to 63,600 kkg/yr
(15,000 to 70,000 tons/yr). The representative facility
size is 40,000 kkg/yr (45,000 tons/yr). The cost variance
with size over this range is estimated to be a
0.9 exponential function for capital and its related annual
costs, and directly proportional for operating costs other
than taxes, insurance, and capital recovery.
202

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TABLE 12
COST	FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY	Fluorspar (flotation)	
PLANT SIZE 40,000	 METRIC TONS PER YEAR OF fluorspar
PLANT AGE 15 YEARS PLANT LOCATION Midwest	

LEVEL
A
(MIN)
B
C
D
E
INVESTED CAPITAL COSTS:
130,000
185,000
185,000


TOTAL
ANNUAL CAPITAL RECOVERY
15,300
21,700
21 ,700


OPERATING AND MAINTENANCE
costs:
24,600
53,700
69,700


ANNUAL 0 & M (EXCLUDING
POWER AND ENERGY)
ANNUAL ENERGY AND POWER
8,000
10,000
10,000


TOTAL ANNUAL COSTS
47,900
85,400
o
o
o


COST/METRIC TON of Product
1.20
2.14
2.54


Y/ASTE LOAD PARAMETERS
(kq/metric Ion of P1-0^0* )
RAW
WASTE
LOAD
5-35
0.3-0.6
0.2-0.4


Suspended solids
2,000
Dissolved fluoride
0.05-0.2
0.05-0.2
0.05-0.2
0.05-0.1






























level description:
A - pond settling and discharge
B - A plus treatment with flocculants
C - A plus alum treatment
203

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Cost. Basis For Table 12
Capital Costs
Pond cost, S/hec-tare ($/acre) : 12,350 (5,000)
Pond size, hectares (acres) : 10 (25)
Operating and Maintenance costs
Labor:	$5.00/hr
Power:	$100/HP-yr
Taxes and insurance: 2% of investment
Flocculating chemicals: $2.20/kg ($1/lb)
Lime:	$22/kkg ($20/ton)
Alum:	$55/kkg ($50/ton)
FLUORSPAR DRYING AND PELLETIZING PLANTS
There are three significant fluorspar drying facilities.
Two of these facilities are dry operations. The third has a
wet scrubber but treats the effluent as part of HF
production wastes. Pelletizing facilities are also dry
operations.
MINE DRAINAGE
Fluorspar mines often have significant drainage. Normally
the fluoride content is 3 mg/1 or less and suspended solids
are low. Even when higher concentrations of suspended
solids are present, settling in ponds is reported to be
rapid. Cost for removing these solids are estimated to be
$0.01 to $0.05 per kkg or ton of fluorspar produced.
204

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SALINES FROM BRINE LAKES
The extraction of several mineral products from lake brines
is carried out at two major U.S. locations: Searles Lake in
California and Great Salt Lake in Nevada. Also lithium
carbonate is extracted at Silver Peak, Nevada. The only
wastes are depleted brines which are returned to the brine
sources. There is no discharge of waste water, no waste
water treatment and no treatment costs.
BORATES
The entire U.S. production of borax is carried out in the
desert areas of California by two processes: the mining and
extraction of borax ore and the trona process. The latter
is covered in the section on salines from lake brines. The
trona process has no waste water treatment or treatment
costs since all residual brines are returned to the source.
The mining and extraction process, which accounts for about
three-fourths of the estimated U.S. production of borax, has
waste water which is evaporated in ponds.
Mining and Extraction Process
All waste water is evaporated in ponds at this facility.
There is no discharge to surface water. Costs for the
ponding treatment and disposal are given in Table 13. Since
there is only one facility, minimum treatment and no
discharge treatment costs are identical.
Cost Variance
Since there is only one facility, age, location and size are
not significant cost variance factors.
Cost Basis for Table 13
Capital Costs
Pond cost, $/hectare ($/acre): 20,000 (8,000)
Pond area, hectares (acres): 100 (250)
Pumps and piping: $500,000
Operating and Maintenance Costs
Pond maintenance: 2% of pond investment
Pump and piping maintenance: 6% of pump and piping investment
Power: $100/HP-yr
Taxes and insurance: 2% of total investment
205

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TABLE 13
COST	FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY	Borates	
PLANT SIZE	'/OP0/000	 METRIC TONS PER YEAR :OF Borates
PLANT AGE 17 YEARS PLANT LOCATION California	

LEVEL
A
(MIN)
B
C
D
E
INVESTED CAPITAL COSTS:
>,500,000




TOTAL
ANNUAL CAPITAL RECOVERY
293,500




OPERATING AND MAINTENANCE
costs:
120,000




ANNUAL 0 Q f/i (EXCLUDING
POWER AND ENERGY)
ANNUAL ENERGY AND POWER
30,000




TOTAL ANNUAL COSTS
443,500




COST/METRIC TOW Borates
0.44





WASTE LOAD PARAMETERS
(kg/nv;ilie toil of Borates )
RAW
WASTE
LOAD
0




Solid wastes (insol.)
800
Soluble wastes
2.5
0
































level description:
A - evaporation of all wastewater in ponds.
206

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POTASH
Potash is produced in four different locations by four dif-
ferent processes, all of which are in dry climate areas of
the western U.S.
Two processes, involving lake brines, have no waste water.
All residual brines are returned to the lake. There are no
treatment costs.
The third process, dry mining followed by wet processing to
separate potash from sodium chloride and other wastes,
utilizes evaporation ponds for attaining no discharge or
waste water. This process and its waste water are described
in Section V, under Carlsbad Operations. Treatment costs
are given in Table 14.
The fourth process, described in Section V under Moab
Operations, involves solution mining followed by wet
separations. This process also has no discharge of waste
water. Treatment costs are given in Table 15.
Cost Variance
Age. Age is not a cost variance factor.
Location. All facilities are located in dry western
geographical locations. Location is not a significant
factor on costs.
Size. Known facility sizes range from 450,000 to
665,000 kkg/yr (500,000 to 730,000 tons/yr) for Carlsbad
Operations. There is only one facility in the Moab
Operations category.
There is no significant cost variance factor with size for
the Moab or Carlsbad Operations subcategories.
Cost Basis for Table 14
Capital costs
Pond cost, $/hectare ($/acre): 2,470 (1,000)
Evaporation pond area, hectares (acres): 121 (300)
Pumps and piping: $100,000
Operating and Maintenance Costs
Maintenance, taxes and insurance: 4% of investment
Power: $100/HP-yr
207

-------
TABLE 14
COST
SUBCATEGORY^
PLANT SIZE
PLANT AGE
30
FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
Potash (Carlsbad Operations)
500,000
YEARS
METRIC TONS PER YEAR OF_
New Mexico
Potash
PLANT LOCATION

LEVEL
A
(I'viiN)
B
C
D
E
INVESTED CAPITAL COSTS;'
400,000




TOTAL
ANNUAL CAPITAL RECOVERY
47,000




OPERATING AND MAINTENANCE
costs:





ANNUAL 0 & t.' (EXCLUDING
POWER AMD ENERGY)
ANNUAL ENERGY AND POWER
8,000




TOTAL ANNUAL COSTS
71,000




COST/METRIC TON Potash
0.14




WASTE LOAD PARAMETERS
I Kq/metric ton of Potash )
RAW
WASTE
LOAD
0




Sodium chloride
0-3750
Clays
15-235
0




Magnesium sulfate
0-640
0




Potassium sulfate
0-440
0




Potassium chloride*
0-318
0











level description:
A - Evaporation ponds
208

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TABLE 15
COST	FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY Potash (Moab Operations)	
PLANT SiZE 20°/000	 METRIC TONS PER YEAR OF Potash
PLANT AGE J?	YEARS PLANT LOCATION uJ°h	

LEVEL
A
(MIN)
B
C
D
E
INVESTED CAPITAL COSTS!
350,000




TOTAL
ANNUAL CAPITAL RECOVERY
56,950




OPERATING AND MAINTENANCE
costs:
45,000




ANNUAL 0 a M (EXCLUDING
POWER AND ENERGY)
ANNUAL ENERGY AND POWER
5,000




TOTAL ANNUAL COSTS
106,950




COST/METRIC ION potash
0.53





WASTE LOAD PARAMETERS
(ka/melric ton of potash) )
RAW
WASTE
LOAD
0




Sodium chloride
640



























	






LEVF± ozscwrtoN:
A - Holding pond plus on-lar.d evaporation
209

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Cost Basis for Table 15
Capital Costs
Dam for canyon: $100,000
Pumps and piping: $250,000
Operating and Maintenance Costs
Labor: $10,000
Maintenance: 8% of investment
Taxes and insurance: 2% of investment
Power: $ 10 0/HP-yr
210

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TRONA
All U.S. mining of trona ore is in the vicinity of Green
River, Wyoming. There are four mining facilities, three of
which also process ore to pure sodium carbonate (soda ash).
The fourth facility has only mining operations at this time.
Wastewater from these operations come from mine drainage,
ground water and process water.
PROCESS WATER
Of the three processing facilities, two have no discharge of
process water and one does. Plans are under way at this one
facility to eliminate process water discharge. Table 16
gives cost estimates for both treatment levels for the
hypothetical representative facility.
Cost Variance
Age. The ages of the three processing facilities range from
6 to 27 years. Age was not found to be a significant factor
in cost variance.
Location. All facilities are located in sparsely populated
areas close to Green River, Wyoming. Geographical location
is not a significant cost variance factor. Local terrain
variations are a factor. Some desired or existing pond
locations give seepage and percolation problems; others do
not. The costs to control seepage or percolation in an area
with unfavorable underlying strata can be considerably more
than the original installation cost of a pond in an area
with no seepage problems. The costs developed in Table 16
are valid for locations with minor pond seepage problems,
which at present is the typical case. For locations with
bad seepage problems, the costs of an interceptor trench to
an impermeable strata plus back-pumping should be added.
Size. Based on 1973 soda ash production figures, the three
processing facilities are roughly of the same size. All of
these facilities are substantially increasing their output
over a period of time. Size is not a significant factor in
cost variance from facility-to-facility.
211

-------
TABLE 16
COST	FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY Trona Ore Mining & Refining (Process Water)
PLANT SIZE 1,000,000	 METRIC TONS PER YEAR -OF Soo'a Ash
PLANT AGE 15 YEARS PLANT LOCATION Wyoming	

LEVEL
A
(MIN)
B
C
D
E
INVESTED CAPITAL COSTS:
1,500,000
2,400,000



TOTAL
ANNUAL CAPITAL RECOVERY
176,100
282,100



OPERATING AND MAINTENANCE
costs:
102,000
160,000



ANNUAL O ft M (EXCLUDING
POWER AND ENERGY)
ANNUAL ENERGY AND POWER
80,000
100,000



TOTAL ANNUAL COSTS
358,100
542,000



COST/METRIC TON soda ash
0.36
0.54



WASTE LOAD PARAMETERS
(kg/mctric Ion of soda ash )
RAW
WASTE
LOAD







Suspended Solids
5
0.005
0



Dissolved Solids
35
0.06
0






			
	




		

	




level description:
A — Evaporation ponds with small discharge
B — Evaporation ponds with no discharge
212

-------
Cost Basis for Table 16
Capital Costs
Pond cost, $/hectare ($/acre): 7,400 (3,000)
Pond area, hectares (acres)
Level A: 162 (400)
Level B: 271 (670)
Pumps and piping
Level A: $300,000
Level B: $400,000
Operating and Maintenance Costs
Pond maintenance: 2% of pond investment
Pump and piping maintenance: 6* of pond investment
Taxes and insurance: 4X of total investment
Power: $100/HP-yr
MINE DRAINAGE
All of the four mines have some drainage. The average flow
mines is 0.64 x 10® 1/day (0.17 mgd). This is approximately
10 percent of average process water and is estimated on this
basis to cost $0.01 to $0.05 per kkg or ton of soda ash
produced for ponding and evaporative treatment. One
facility currently has an unusually high mine pumpout
volume, 1.8 x 10® 1/day (0.43 mgd). The costs to contain
and evaporate this amount is proportionately higher.
GROUND WATER AND RUNOFF WATER
Ground water and runoff water is also led to collection
ponds where settling and substantial evaporation take place.
On the basis of known information no meaningful cost
estimate can be made, since the amounts are extremely
variable and, nevertheless, small compared to the process
water volume.
213

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SODIUM SULFATE
Sodium sulfate is produced from natural sources in three
different geographical areas by three different processes:
(1)	Recovery from Great Salt Lake brine;
(2)	Recovery from Searles Lake brines;
(3)	Recovery from west Texas brines.
Processes (1) and (2) have been discussed under Salines by
Brine Lake Mining and have no waste water treatment or
treatment costs. All residual brines are returned to the
lakes. process (3) has waste water which is percolated and
evaporated in existing mud flat lakes. There is no
treatment construction. The waste water flows to the mud
lake by gravity. Costs are almost negligible (estimated as
$0.01 to $0.05 per metric ton or short ton of sodium sulfate
produced).
214

-------
ROCK SALT
This study covers those facilities primarily engaged in
mining, crushing and screening rock salt. Some of these
facilities also have evaporation operations with a common
effluent.
Mining, Crushing and Screening Operations
The waste water from mining, crushing and screening
operations consists primarily of a solution of varying
sodium chloride content which comes from one or more of the
following sources:
(1)	wet dust collection in the screening and sizing step;
(2)	washdown of miscellaneous spills in the operating area
and dissolving of the non-saleable fines;
(3)	seepage from mine shafts.
Wastewater volumes are usually fairly small, less than
500,000 1/day (130,000 gal/day), and are handled in various
ways, including well injection and surface disposal. Well
injection costs for minewater drainage are estimated to be
in the range of $0.01 to $0.05 per kkg or short ton of salt
produced. surface disposal is costed in Table 17. Most
often there is no treatment of the miscellaneous saline
waste water associated with this subcategory. Some
facilities use settling ponds to remove suspended solids
prior to discharge. In the event that land is not available
for ponds, costs for alternate technology using clarifiers
instead of ponds are given in Level C.
Cost Variance
Age, location, and size are not significant factors in cost
variance.
Cost Basis For Table 17
Capital costs
Pond cost, $/hectare ($/acre): 49,000 (20,000)
Pond size, hectares (acres): 0.2 (0.5)
Pumps and piping cost: $5,000
Clarifier: $35,000
215

-------
TABLE 17
COST	FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY Rock Sail* (Mining, Crushing and Screening)
PLANT SIZE	1,000,000	METRIC TONS PER YEAR -'OF salt
PLANT AGE 30 YEARS PLANT LOCATION Eastern United States 	

LEVEL
A
(MIN)
0
B
C
D
E
invested capital costs:
15,000
50,000


TOTAL
ANNUAL CAPITAL RECOVERY
0
1,760
8,150


OPERATING AND MAINTENANCE
costs:
0
700
3,000


ANNUAL 0 G M (EXCLUDING
POWER AND ENERGY)
ANNUAL ENERGY AND POWER
0
500
3,000


TOTAL ANNUAL COSTS
0
2,960
13,150


COST/f/.ETRIC TON salt
0
<0.01
0.01


WASTE LOAD PARAtViETf.RS
(l;q/rnoiric ton of salt )
RAW
WASTE
LOAD







Suspended solids
0-0.9
0-0.9
0,009
0.009








	

	

















level inscription:
A — No wastewater treatment
B — Pond settling of suspended solids foilov/ed by discharge
C — Clarifier removal of suspended solids followed by discharge
216

-------
Opera-ting and Maintenance
Pond maintenance: 2% of pond investment
Pump and piping maintenance: 10% of pump and piping investment
Power: $100/HP-yr
Taxes and insurance: 2% of total investment.
217

-------
PHOSPHATE ROCK
Phosphate ore is	mined in four different regions of the
U.S.:
Florida:	18% of production
North Carolina:	5% of production
Tennesse:	5% of production
Western States:	12% of production
For purposes of waste water treatment technology and costs
categorization the above production may be separated into
two subcategories: eastern operations and western
operations.
EASTERN OPERATIONS
The beneficiation of phosphate ore involves large wastewater
effluents. In addition, there are large guantities of solid
wastes. Raw wastes, sand, and small particle sized slimes,
suspended in the process effluents, exceed the quantity of
phosphate product. Essentially two waste water streams come
from the process: sand tailings stream and a slimes stream.
The sand tailings settle rapidly for use in land
reclamation. The water from this stream can then be
recycled. Slimes, on the other hand, settle fairly rapidly
but only compact to 10-20 percent solids. This soft, non-
weight- bearing mud ties up both massive quantities of water
and volumes of retention ponds. Most of the process waste
water treatment costs are also tied up in the construction
of these slime ponds. Massive dams and dikes are
constructed around these ponds. All mine and beneficiating
facilities practice complex water control and reuse. The
extent of control and reuse depends on many factors,
including:
(1)	topography
(2)	mine-beneficiating facility waste pond layouts
(3)	age of facilities
<<0 fresh water availability
(5)	regulations
(6)	level of technology employed
(7)	cost.
Most water discharges are intermittent; heavy during the wet
season (3-6 months/yr), slight or non-existent during dry
seasons (6-9 months/yr). Water discharged during the wet
season due to insufficient storage capacity could be used
during the dry season, if available.
218

-------
Since water control fundamentally involves storage and
transport (pumping) operations, by construction of
additional storage pond and piping and pumping facilities
almost any degree of process waste water control may be
achieved up to and including closed cycle. No discharge of
process water involves two premises:
(1)	Only process water is contained. Mine drainage is
isolated and used as feed water or treated (if needed)
and discharged separately. Rainwater runoff is also
treated separately, if needed.
(2)	Evaporation-rainfall imbalances are more than counter-
balanced by water losses in slime ponds. Slime ponds
are essentially water accumulation ponds where water is
removed from recycle by holdup in the slimes.
All costs are for treatment and storage of suspended solids.
There is no treatment applied specifically for fluorides or
phosphates although existing treatment will result in a
degree of removal of these pollutants. Table 18 gives costs
for three levels of treatment technology. All facilities
use Level A technology, and most use some degree of Level B
technology. Level C technology is currently not used. All
discharged wastes are expressed in concentrations, since
volume of wastewater discharges from the facilities vary
widely depending on age, terrain, local rainfall, and water
control practice. Most facilities currently achieve less
than 30 mg/1 suspended solids at Level A. Those that do not
would be expected to have the additional expenditures of
Level B to reach 30 mg/1 suspended solids.
Cost Variance
Age. Facilities representing the eastern phosphate rock
suEcategory range in age from 3 to 37 years. Age was not
found to be significant factor in cost variance.
Location. Operations are located in Florida, North Carolina
and Tennessee. Pond construction is different in Tennessee,
which is hilly, than in flat areas such as Florida and North
Carolina. Flat area facilities have diked ponds while in
Tennessee facilities use dammed valleys. A comparison
indicates that construction costs are approximately the same
for both areas and location is not a significant factor in
cost variance.
Size. The facilities in the eastern subcategory range in
size from 46,300 to 4,090,000 kkg/yr (51,000 to
4,500,000 tons/yr). The representative facility is
2,000,000 kkg/yr (2,200,000 tons/yr). The cost variance
with size is estimated to be a 0.9 exponential function for
219

-------
COST
SUCCATEGORY Phosphate Rock (Eastern)
TABLE 18
FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
PLANT SIZE	2,000,000	METRIC TONS PER YEAR -OF product-
PLANT AGE 15 YEARS PLANT LOCATION Florida- North Carol ino-Tennessee

LEVEL
A
(MIN)
B
C
D
E
INVESTED CAPITAL COSTS!
8,000,000
8,650,000
1 2,000,000


TOTAL
ANNUAL CAPITAL RECOVERY
804,000
910,000
1,560,000


OPERATING AND MAINTENANCE
costs:
360,000
389,000
429,000


ANNUAL 0 G M (EXCLUDING
POWER AND ENERGY)
ANNUAL ENERGY AND POWER
240,000
300,000
335,000


TOTAL ANNUAL COSTS
1,404,000
1,599,000
2,324,000


COST/METRIC TON product
0.70
0.80
1.16



WASTE LOAD PARAMETERS
(mg/liter)
RAW
WASTE
LOAD







Suspended Solio's

3-560
<30
0


Dissolved Fluoride

2*
2*
0


Phosphorus (total)

4*
4*
0

I














Estimal ecTaverage~vaTues
i. evel description:
A — Pond treatment of slirnes and sand tailings
B — A plus improved process water segreation
C — Pond treatment plus impoundment of all process water
220

-------
capital and its related annual costs, and directly
proportional for operating costs other than taxes, insurance
and capital recovery.
Cost Basis For Table 18
Capital Costs
Pond cost, $/hectare ($/acre): 17,300 (7,000)
Pond area, hectares (acres):	400 (1,000)
Pumps and piping:	$1,000,000
Operating and Maintenance Costs
Labor and maintenance: 2.5% of total investment
Taxes and insurance: 2% of total investment
Power: $ 10 0/HR-yr
WESTERN OPERATIONS
Because of the favorable rainfall-evaporation balance
existing for western phosphate mines and processing
facilities, all facilities are either at the no discharge
level or can be brought to this level. Of six operating
areas, five have no discharge.
Table 19 gives cost of waste water treatment technology for
western operation.
Cost Variance
Age. The six western operations range in age from 6 to
27 years. Age was not found to be a significant cost
variance factor.
Location. All facilities in this subcategory are located in
IdahoJ Wyoming and Utah. Location is not a significant cost
variance factor.
Size. Facilities in this subcategory range in size from
2967000 to 909,000 kkg/yr (326,000 to 1,000,000 tons/yr).
The	representative	facility is 500,000 kkg/yr
(550,000 tons/yr). Over this range of sizes, capital costs
variance can be estimated by an exponent of 0.9 to size and
operating costs other than capital recovery, taxes and
insurance are approximately proportional to size.
221

-------
TABLE 19
COST	FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUB CAT EG ORY phosphate Rock	
PLANT SIZE	500,j000	METRIC TONS PER YEAR "OF product-
PLANT AGE 10 YEARS PLANT LOCATION Idaho-Utah	

LEVEL
A
(MIN)
B
c
D
E
INVESTED CAPITAL COSTS!
850,000
1,250,000



TOTAL
ANNUAL CAPITAL RECOVERY
93,500
140,500



OPERATING AND MAINTENANCE
costs:
38,500
56,500



ANNUAL 0 & M (EXCLUDING
POWER AND ENERGY)
ANNUAL ENIixGY AND POWER
50,000
75,000



TOTAL ANNUAL COSTS
182,000
272,000



COST/i.'ETRIC TON product
0.36
0.54



WASTE LOAD PARAMETERS
(kq/motric ton of product )
HAW
WASTE
LOAD







Suspended solids
1700
<0.05
0



Fluoride (as ion)
-
<0.001
0



Phosphorus (total)
-
<0.001
0

















LEVEL description:
A — Thickener plus evaporation ponds; discharge of residual to surface water
B — Level A plus additional evaporation ponds to give no discharge.
222

-------
Cost Basis For Table 19
Capital Costs
Pond costs, $/hectare ($/acre): 4,900 (2,000)
Pond size , hectares (acres):	100 (250)
Thickener: $200,000
Pumps and piping: $150,000
Operating and Maintenance Costs
Labor and maintenance
Power:
Taxes and insurance:
2.5% of investment
$100/HP-yr
256 of investment
MINE DRAINAGE
The high water table plus the heavy seasonal rainfall in
most of the eastern mining areas usually causes the mining
pits to collect water. Whenever feasible, mine drainage is
used for slurrying phosphate matrix to the beneficiation
process. When this is not possible, drainage can be pumped
into other mined out pits. Mine drainage involves primarily
on-property water control. Any that is may be expected to
be treated as waste water. Treatment costs are roughly
estimated at $0.01 to $0.05 per kkg or ton of product.
223

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SULFUR (FRASCH PROCESS)
There are two subcategories of sulfur mining:
(1)	anhydrite deposit mining;
(2)	on-shore salt dome mining;
ANHYDRITE DEPOSIT MINING
The following is a comparison of waste water from mining of
sulfur from anhydrite deposits to that from mining of salt
dome deposits:
(1)	The porous structure of anhydrite deposits absorbs more
of the injected water and reduces the amount of bleed-
water.
(2)	Since the anhydrite deposits are not filled with salt,
bleedwater is lower in dissolved solids than the average
for salt dome bleedwater. Anhydrite mines recycle this
bleedwater to the formation.
(3)	The location of anhydrite mines is in western Texas
where the dry climate makes it possible to evaporate
waste water. Salt dome mines are in Louisiana and east
Texas which have more rainfall.
Treatment and cost options are developed in Table 20 for
complete recycle of anhydrite deposit mining bleedwater.
Since both anhydrite deposit mines are now accomplishing
this level, the costs also represent minimum level treatment
technology.
Most of the costs in Table 20 are for water treatment
chemicals for the recycled bleedwater.
Cost Variance
Age. The anhydrite deposit mining subcategory consists of
two facilities, 5 and 7 years of age. Age is not a
significant cost variance factor.
Location. Both facilities are located in western Texas.
Location is not a significant cost variance factor.
Size. Based on water treatment costs supplied by both
facilities, size in existing facilities is not a significant
cost variance factor.
224

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TABLE 20
COST	FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY Sulfur (Anhydrite Deposit Mining)
PLANT SIZE 1,000,000	METRIC TONS PER YEAR OF sulfur
PLANT AGE 6 YEARS PLANT LOCATION	Western Texos

LEVEL
A
(i'/ilN)
550,000
B
C
D
E
INVESTED CAPITAL COSTS;
TOTAL




ANNUAL CAPITAL RECOVERY
90,000




OPERATING AND MAINTENANCE
costs:
ANNUAL 0 O M {EXCLUDING
power and energy)
705,000




annum. energy AND POWER
30,000




TOTAL ANNUAL. COSTS
825,000




COST/METRIC TON sulfur
0.83




WASTE LOAD PARAMETERS
(kg/metric Ion of sulfur )
RAW
WASTE
LOAD





Water softener sludge
12.5
Suspended solids
-
0




Dissolved solic's
~2r.o"
43.9
0

























level description:
A — Recycle of all bleedwater, use of on-site evaporative disposal of water
softener sludges.
225

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Cost Basis For Table 20
Capital Costs
Water treatment installations:
Thickeners and evaporation ponds:
Pumps and piping:
$300,000
$100,000
$150,000
Operating and Maintenance Costs
Bleedwater volume, 1/day (mgd) : 18.9 x 10# (5.0)
Bleedwater treatment, $/1#000 liters (gallons): $0.09 ($0.35)
Energy and power costs supplied by facility 2020
ON-SHORE SALT DOME MINING
There are nine facilities in the U.S. producing sulfur from
on-shore salt dome operations. The wide variability of
bleedwater quantity per ton of sulfur produced has been
taken into account by expressing all pollutants in terms of
concentration rather than weight units.
Cost-benefit analyses for on-shore salt dome sulfur
facilities are given in Table 21. Several companies are
using (or have used) Level A technology, at least one uses
Level B as part of their treatment and process, one uses
Level c, five use Level D, one uses Level E, one Level F and
no one currently uses Level G. Level G is included for two
purposes:
(1)	to show the costs for complete oxidation of all
sulfides, in the bleedwater to sulfates, and
(2)	to show that once the bulk of the oxidation has been
achieved by other means, chemical treatment with
chlorine for removal of the small residual oxygen demand
may be the most practical approach.
Cost Variance
Age. The on-shore salt dome sulfur mining subcategory
consists of 9 facilities ranging in age from 6 to H5 years.
Age is not a significant cost variance factor.
Location. All facilities are located in eastern Texas and
Louisiana. Geographical location is a significant cost
variance factor only in that lengthy ditches (up to 37 km or
22 miles) often had to be dug to get the bleedwater
discharge to suitable surface water. All facilities now
have such outlets. New facilities in this subcategory would
have to make such provisions, quite likely at major expense.
226

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TABLE 21
COST	FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY Sulfur (Solt Porno, On-Shoro)	
PLANT SIZE 500,000	 METRIC TON'S PER YEAR -OF sulfur
PLANT AGE 26 YEARS PLANT LOCATION Louisionn-East Texas	

LEVEL
A
(M!N)
B
C
D
E F
G
INVESTED CAPITAL COSTS!
50,000
50,000
1,540,000
3,200,000
1,500,000 3,000,000
20,000
TOTAL
ANNUAL CAPITAL RECOVERY
5,870
5,870
250,000
375,700
176,000 488,000
3,200
OPERATING AND MAINTENANCE
costs:
ANNUAL 0 Q 1.1 (EXCLUDING
POWER AND ENERGY)
2,500
5,000
145,000
102,000
i
I
I
300,000 | 415,000
i
|
3,400,000
ANNUAL ENERGY AKD POWER
1,000
20,000
10,000
10,000
100,000
25,000
1,000
TOTAL ANNUAL COSTS
9,370
30,870
405,500
488,400
570,000
928,000
3,404,000
COST/METRIC TON sulfur
0.02
0.06
0.81
0.98
1.15
1.86
6.80
WASTE LOAD PARAMETERS
RAW
WASTE
LOAD






i
i


Sulfide, mn/litcr
600-
-rale21-
„JŁQ0_
500
200-400
<5
<10
<5
<5
0
BOD, mg/liter
500
200-400
5
10
10
400
0
COD, mg/iiter
6T/J-
1000
<60
500
200-400
50
<100
50
500
0	
<50
Suspended solids, mn/litcr
<50
<50
<50
<50
<50
30









level inscription:
A — Flushing of hydrogen sulfide from bleedwoter
B — Sproy oeration
C — Flue gos si l ipping reoclion plus ponding
D — Large oxidalion and settling ponds
E — Aeration in smoll ponds followed by mixing of partially treated bleedwoter with
10-20 limes its volume of oxygon-containing water
F-Ch '.imical treatment will) sulfuious acid
G —Chemical treatment with chlorine
227

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Size
The nine facilities in this subcategory range from 150,000
to 1,270,000 kkg/yr (165,000 to 1,400,000 tons/yr). The
representative facility is 500,000 kkg/yr (550,000 tons/yr).
The capital costs over this size range are estimated to be
an 0.8 exponential function of size for process equipment
treatment facilities such as Levels C and F, 0.9 exponential
for mixed facilities such as Level E and directly
proportional to size for Level D pond treatment. Operating
costs other than taxes, insurance and capital recovery are
estimated to be proportional to size.
Relative Bleedwater Volume
The costs are assumed to be directly proportional to the
bleedwater volume per unit of production. Exclusive of sea
water dilution, the range of relative bleedwater volumes
found was 6,900 to 22,100 1/kkg (1,700 to 5,300 gal/ton).
Cost Basis For Table 21
Capital Costs
Capital costs for Levels C through F of Table 23 were taken
from industry supplied values and adjusted for size.
Level G is based on 500 mg/1 of sulfides in 18.9 x 106 1/day
(5 mgd of bleedwater).
Operating and Maintenance Costs
Operating and maintenance costs for Levels C through F of
Table 21 were taken from industry supplied values.
Chlorine costs for Level G, $/kkg ($/ton): 110 (100)
Off-shore Salt Dome Mining
There is only one operational off-shore salt dome facility.
Bleedwater is directly discharged without treatment into the
Gulf of Mexico. Dissolved methane gas occurring naturally
in the bleedwater provides initial turbulent mixing of
bleedwater and sea water. Dissolved oxygen in the sea water
reacts with the sulfides present.
Current treatment (none) and two additional treatment
technologies and their estimated costs are given in Table
22. Level A represents present technology; Level B is
piping of all bleedwater to shore (10 miles away) followed
by on-shore ponding treatment; Level C is off-shore chemical
treatment of sulfides with chlorine. Level B is predicated
228

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COST
TABLE 22
FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY Sulfur (Off-Shore Salt Dome)
PLANT SIZE 1,000,000	METRIC TONS PER YEAR OF sulfur
PLANT AGE 14 YEARS PLANT LOCATION Off-Shore Louisiana

LEVEL
A
(M!,\!)
B
C
D
E
INVESTED CAPITAL. COSTS!
0
13,750,000
7,920,000


TOTAL
ANNUAL CAPITAL RECOVERY
0
2,237,000
1,288,600


OPERATING AND MAINTENANCE
costs:
0
1,385,000
6,212,000


ANNUAL 0 C; 1': (EXCLUDING
POWER AND ENERGY)
ANNUAL ENERGY AND POWER
0
200,000
100,000


TOTAL ANNUA!_ COSTS
0
3,822,000
7,600,600


COST/i.'ETRIC TON sulfur
0
3.82
7.60



WASTE LOAD PARAMETERS
(ka/mciric Ion of sulfur )
R AW
WASTE
LOAD







Suspended Solids
0.3
0.3
0.2
0.2


Sulfides
5.5
5.5
0.03
0.03


COD
11
11
0.3
0.3
















Li\Vfri. DEscmrnioN:
A — Use of oxygen in seawater to oxidize sulfides
B — All bleedwuter pumped to shore followed by on-shore ponding and mixing
with ambient water to oxidize sulfides
C — Off-shore chemical oxidation of sulfides with chlorine
229

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on right-of-way and land availability, which has yet to be
established, for pipeline and pond construction. Level C
technology is not currently utilized in any existing sulfur
production facility. In view of the high attendant costs
and questionable feasibility of both additional treatment
technology options, present treatment technology is believed
to be the best economically achievable.
Cost Variance
For the single facility, age, geographical location and size
variances are not applicable within this subcategory.
Cost Basis For Table 22
Capital Costs
Pumps and piping:
Land cost, $/hectare ($/acre):
Land area, hectares (acres) :
Pond cost, $/hectare# ($/acre) :
Dilution pumping station:
New off-shore platforms:
Pumps and piping:
Chemical treatment facilities:
Construction overhead:
Operating and Maintenance Costs
Labor and maintenance:	8% of investment
Power:	$ 10 0/HP-hr
Chlorine, dollars/kkg (dollars/ton): 110 (100)
Taxes and insurance: 2% of investment costs
$10,200,000
12,300 (50,000)
40	(100)
6,200 (2,500)
$520,000
$4,200,000
$2,200,000
$200,000
20X of direct costs
230

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MINERAL PIGMENTS (IRON OXIDE PIGMENTS)
Processing of ore to pigment uses either of two processes
depending on the source and purity of the ore. For
relatively pure ores, processing consists simply of crushing
and grinding followed by air classification. This is a dry
process which uses no water and has no treatment costs.
Alternatively, for less pure ores, a washing step designed
to remove sand and gravel, followed by dewatering and drying
is used. This process has waste water treatment costs.
Table 23 gives cost estimates for waste water treatment for
this wet process.
Cost variance
Age. The one facility found using the wet process has an
age of 50 years. Age is not believed to be a significant
factor for cost variance.
Location. Location was not found to be a significant factor
for~cost variance.
Size. Only one facility was found using the wet process,
size is not believed to be a significant factor for cost
variance.
Cost Basis For Table 23
Capital Costs
pond cost, $/hectare ($/acre): 24,700 (10,000)
Settling pond area, hectares (acres):	0.40 (1)
Pumps and piping:	$5,000
operating and Maintenance Costs
Maintenance: 4% of investment
Power: $10 0/HP-yr
Taxes and insurance: 2% of investment
231

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COST
TABLE 23
FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY Mineral Pigments (Wet Process)	
PLANT SIZE 3/000	METRIC TONS PER YEAR ¦ OF product
PLANT AGE 50 YEARS
PLANT LOCATION
Eastern United States

LEVEL
A
(MINI)
B
C
D
E
INVESTED CAPITAL COSTS:
15,000
20,000



TOTAL
ANNUAL CAPITAL RECOVERY
1,750
2,530



OPERATING AND MAIM1 ENANCE
costs:
900
1,200



ANNUAL 0 G; M (EXCLUDING
POWER AND ENERGY)
ANNUAL ENERGY AND POWER
500
1,000



TOTAL ANNUAL COSTS
3,250
4,550



COST/METRIC TON product
1 .08
1.52



WASTE LOAD PARAMETERS
(kg/msiric ton of product )
RAW
WASTE
LOAD
2.3
0



Suspended Solids
—



































level inscription:
A — Pond settling and discharge
B —¦ Pond settling and total recycle
232

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LITHIUM MINERALS
There are only two facilities mining and processing
spodumene ore in the U.S. At both facilities the process
water recycle is 90 percent or greater. The remainder is
discharged. Large volumes of solid wastes are inherent to
the process. These wastes are stored and/or disposed of by
a combination of the following means:
(1)	Landfill or land storage as solids;
(2)	Storage as settled solids in ponds;
(3)	Processing and recovery as salable by-products; and
(4)	A small portion is discharged to surface water as
suspended or dissolved materials.
The two facilities differ as to the above options employed.
Processing and recovery or by-products also introduces new
wastes into the waste water that are not present otherwise.
Therefore, the treatment technologies and costs developed in
Table 24 represent the best estimate of composite values for
both facilities. Level A represents present performance and
Level B future performance. Level B is based mainly on
projected installations for which the two facilities have
supplied technology and cost information.
Cost Variance
Age. Age was not found to be a significant factor in cost
variance.
Location. Both facilities are located in North Carolina.
Geographical location is not a significant factor in cost
variance.
Size. The facilities are of the same approximate size.
Size is not a significant factor in cost variance.
Cost Basis For Table 24
Capital Costs
Pond costs, $/hectare ($/acre): 7,400 (3,000)
Pond area, hectares (acres):	50 (125)
pumps and piping:	$100,000
233

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TABLE 24
COST	FOR A REPRESENTATIVE PLANT
(ALL COSTS ARE CUMULATIVE)
SUBCATEGORY Lithium Minerals
PLANT AGE 15 YEARS PLANT LOCATION North Carolina

LEVEL
A
(MiN)
B
C
D
E
INVESTED CAPITAL COSTS".-
475,000
725,000



TOTAL
ANNUAL CAPITAL RECOVERY
77,300
128,000



OPERATING AND MAINTENANCE
costs:
133,000
212,000



ANNUAL, 0 & \A (EXCLUDING
POWER AND ENERGY)
ANNUAL ENERGY AND POWER
10,000
15,000



TOTAL ANNUAL COSTS
220,300
340,000



COST/METRIC TON ^centrate
4.90
7.56



WASTE LOAD PARAMETERS
spodumene
(kg/metric ton of concentrate
RAW
WASTE
LOAD
)
0.9
0.9



Suspended Solids
100-
620
Iron

0.038
0.02



Fluoride
-
0.14
0.07



Manganese
-
0.11
0.05

















level description:
A — Ponding of wastewater to remove suspended solids plus 90% recycle of mine and
process wastewater
B — Level A plus segregation and treatment of additional wastewater streams plus 95%
recycle of all mine and process wastewater
234

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Operating and Maintenance Costs
Pond maintenance:
Non-pond maintenance:
Labor cost:
Power:
Chemical:
2% of invested pond capital
6% of invested non-pond capital
$10,000/man-yr
$100/HP-yr
$100,000/yr
MINE DRAINAGE
Mine drainage is less than 10 percent of the total waste
water volume and is now partially treated with the process
waste water. Rough estimates for treating any necessary
residual mine drainage water are $0.01 to 0.05/kkg of
product produced.
235

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SECTION IX
EFFLUENT REDUCTION ATTAINABLE THROUGH THE
APPLICATION OF THE
BEST PRACTICABLE CONTROL TECHNOLOGY
CURRENTLY AVAILABLE
INTRODUCTION
The effluent limitations which must be achieved by July 1,
1977, are based on the degree of effluent reduction
attainable through the application of the best practicable
control technology currently available. For the mining of
minerals for the chemical and fertilizer industries, this
level of technology was based on the average of the best
existing performance by facilities of various sizes, ages,
and processes within each of the industry^ subcategories.
In Section IV, this segment of the minerals mining and
processing industry was divided into twelve major
categories. Several of these major categories have been
further subcategorized and, for reasons explained in Section
IV, each subcategory will be treated separately for the
recommendation of effluent limitations guidelines and
standards of performance.
Best practicable control technology currently available
emphasizes treatment facilities at the end of a
manufacturing process but also includes the control
technology within the process itself when it is considered
to be normal practice within an industry. Examples of waste
management techniques which were considered normal practice
within these industries are:
(a)	manufacturing process controls;
(b)	recycle and alternative uses of water; and
(c)	recovery and/or reuse of some waste water constituents.
Consideration was also given to:
(a)	the total cost of application of technology in relation
to the effluent reduction benefits to be achieved from
such application;
(b)	the size and age of equipment and facilities involved;
(c)	the process employed;
(d)	the engineering aspects of the application of various
types of control techniques;
(e)	process changes; and
(f)	non-water quality environmental impact (including energy
requirements).
237

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The following is a discussion of the best practicable
control technology currently available for each of the
subcategories, and the proposed limitations on the
pollutants in their effluents.
GENERAL WATER GUIDELINES
Process Water
Process water is defined as any water contacting the ore,
processing chemicals, intermediate products, by-products or
products of a process including contact cooling water during
processing. All process water effluents are limited to the
pH range of 6.0 to 9.0 unless otherwise specified.
Process generated waste water is defined as any water which
in the mineral processing operations such as crushing,
washing and beneficiation, comes into direct contact with
any raw material, intermediate product, by-product or
product used in or resulting from the process.
Where sufficient data was available a statistical analysis
of the data was performed to determine a monthly and a daily
maximum. In most subcategories, where there is an allowable
discharge, an achievable monthly maximum was determined from
the data available.
A detailed analysis of the ratio of daily TSS to monthly TSS
maximum at a 99 percent level of confidence for large
phosphate slime ponds indicates that a TSS ratio of 2.0 is
representative of a large settling pond treatment system,
and this ratio was used where there was insufficient data to
predict a daily maximum directly.
A ratio of 2.0 was also used for parameters other than TSS.
It is judged that this is an adequate ratio since the
treatment systems for F, Zn and Fe for instance have
controllable variables, such as pH and amount of lime
addition. This is in contrast to a pond treating only TSS
which has few if any operator controllable variables.
Cooling Water
In the minerals mining and processing industry, cooling and
process waters are sometimes mixed prior to treatment and
discharge. In other situations, cooling water is discharged
separately. Based on the application of best practicable
technology currently available, the recommendations for the
discharge of such cooling water are as follows:
238

-------
An allowed discharge of all non-con-tact, cooling waters
provided that the following conditions are met:
(a)	Thermal pollution be in accordance with EPA standards.
Excessive thermal rise in once through non-contact
cooling water in the mineral mining industry has not
been a significant problem.
(b)	All non-contact cooling waters should be monitored to
detect leaks of pollutants from the process. Provisions
should be made for treatment to the standards
established for process waste water discharges prior to
release in the event of such leaks.
(c)	No untreated process waters be added to the cooling
waters prior to discharge.
The above non-contact cooling water recommendations should
be considered as interim, since this type of water plus
blowdowns from water treatment, boilers and cooling towers
will be regulated by EPA as a separate category.
Mine Drainage
Mine drainage is any water drained, pumped or siphoned from
a mine.
Storm Water Runoff
Untreated overflow may be discharged from process waste
water or mine drainage impoundments without limitation if
the impoundments are designed, constructed and operated to
contain all process generated waste water or mine drainage
and surface runoff into the impoundments resulting from a 10
year 24 hour precipitation event as established by the
National Climatic center. National Oceanic and Atmospheric
Administration for the locality in which such impoundments
are located. To preclude unfavorable water balance
conditions resulting from precipitation and runoff in
connection with tailing impoundments, diversion ditching
should be constructed to prevent natural drainage or runoff
from mingling with process waste water or mine drainage.
239

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PROCESS WASTEWATER GUIDELINES AND LIMITATIONS
BARITE (DRY PRODUCTION SUBCATEGORY
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of process generated waste water pollutants
because no process water is used.
The mine drainage and process contaminated runoff	should be
held to a daily maximum of 35 mg/1 TSS based on	the data
from other subcategories. No mine drainage was	found for
this subcategory.
BARITE (WET-LOG WASHING AND JIGGING AND FLOTATION)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
no discharge of process waste water pollutants. The
following limits apply to process water pond discharges
resulting from rainfall and to mine drainage.
Effluent Characteristic
process waste water TSS
mine drainage TSS
(acid mine water) dissolved
Effluent Limitation
mg/1 ~
Monthly Average Daily Maximum
15	30
35	70
Fe 0.3	0.6
There is no discharge of process waste water pollutants
during normal operating conditions. The above limitations
apply to discharges occurring during heavy rainfall. The
quantity of water used in this subcategory is independent of
the quantity of product. Therefore, effluent limitations
based on quantity of pollutant per unit of production are
not practical. There is one mine experiencing acid mine
drainage and is currently building a treatment system. Best
practicable control technology currently available for the
mining and processing of barite by the wet processes is
containment of process waste water, settling of suspended
solids, and recycle of process water during normal operating
conditions. Where there is a discharge during periods of
heavy rainfall, settling of suspended solids by ponding,
flocculation, coagulation or other methods may be necessary.
Four facilities in these subcategories in the same net
precipitation geographical location are currently achieving
this limitation.
240

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FLUORSPAR (HMS)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of process generated waste water pollutants.
Best practicable control technology currently available for
the mining and processing of fluorspar by the HMS process is
impountment of process water and total recycle. To
implement this technology at the one facility not already
using the recommended control techniques would require the
installation of recycle equipment. Five of the six
facilities studied are presently utilizing the recommended
technologies.
FLUORSPAR (FLOTATION)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation
kq/kkq of"product 7lbs7l000 lbl
Effluent_Characreristic Monthly Average	Daily Maximum
TSS	0.6	1.2
dissolved fluoride 0.2	0.4
The above limitations are based on the anticipated
performance of treatment systems currently being installed
at two facilities {facilities 2000 and 2001) . Best
practicable control technology currently available for the
mining and processing of fluorspar by the flotation process
is ponding in series and flocculation to reduce suspended
solids and fluoride prior to discharge. An alternative
BPCTCA is ponding and evaporation where possible. To
implement this technology at facilities not already using
the recommended control techniques would require the
installation of ponds in series and flocculant addition
facilities. Two facilities are presently installing the
recommended technologies.
FLUORSPAR (DRYING AND PELLETIZING)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of process generated waste water pollutants
because there is no process water.
241

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MINE DRAINAGE AND PROCESS CONTAMINATED RUNOFF
Information contained in Sections V through VIII show that
mine drainage and process contaminated runoff can meet as a
daily maximum: TSS 30 mg/1
SALINES FROM BRINE LAKES (SEARLES LAKE)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no net discharge of process waste water pollutants. Best
practicable control technology currently available for the
mining and processing of salines from brine lakes by the
Searle Lake process is return of depleted brines and liquor
to the brine source. The two facilities in this production
subcategory are presently using the recommended control
technologies.
SALINES FROM BRINE LAKES (GREAT SALT LAKE)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no net discharge of process waste water pollutants. Best
practicable control technology currently available for the
mining and processing of salines from brine lakes by the
Great Salt Lake process is the return of depleted brines and
liquor to the brine source. The only facility in this
production subcategory is presently using the recommended
control technology.
SALINES FROM BRINE LAKES (SILVER PEAK)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no net discharge of process waste water pollutants. Best
practicable control technology currently available for the
mining and processing of salines from brine lakes by the
Silver Peak process is the return of depleted brines and
liquor to the brine source. The only facility in this
production subcategory is presently using the recommended
control technology.
242

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BORAX
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of process waste water pollutants. Best
practicable control technology currently available for the
mining and processing of borax is the use of lined
evaporation ponds. The only facility in this subcategory
presently uses the recommended technology.
POTASH
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of process waste water pollutants. Best
practicable control technology currently available for the
mining and processing of potash by either the dry mining or
solution mining process is the use of evaporation ponds to
contain process water. All facilities in this subcategory
are presently using the recommended technology.
TRONA
Based upon the information contained in sections III through
VIII0 a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of process waste water and mine drainage
pollutants. Best practicable control technology currently
available for the mining and processing of trona orte and
conversion to soda ash is total impoundment and evaporation
of all process waste water and mine water. To implement
this technology at facilities not already using the
recommended control techniques would require construction of
total impoundment evaporation ponds. All facilities use
this technology to dispose of process waste water.
SODIUM SULFATE (BRINE WELL)
Based upon the information contained in Sections III through
VIII0 a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of process waste water pollutants. Best
practicable control technology currently available for the
mining and processing of sodium sulfate by the brine well
extraction process is total impoundment and evaporation of
all process waste water. The two facilities representing
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this production subcategory are presently using the
recommended control technologies.
ROCK SALT
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation
kg/kkq of product
(lbs/1000 lb)
Effluent Characteristic Monthly Average	Daily Maximum
TSS	0.02	0.04
The above limitations are based on the performance currently
achievable by at least three facilities.
Mine water discharge and process contaminated runoff for
this subcategory are included in the above limitations.
Best practicable control technology currently available for
the mining and processing of rock salt is the control of
casual water with good water management practices and
settling where required. To implement this technology at
facilities not already using the recommended control
techniques would require better water management practices
and the installation of adequate settling facilities where
required. At least three facilities are presently achieving
the recommended limitations with the use of the
technologies.
PHOSPHATE ROCK
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation
Effluent	MonthIv**Averaqe Daily Maximum
Characteristic
TSS	30 mg/1	70 mg/1
Total radium 226	5 pCi/1
These limits apply to the quantity of water used in the
flotation circuits which cannot be economically recycled,
because of excessive costs, and the mine water and rainfall.
These latter two water sources necessitate using a
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concentration rather than a mass unit because they are
production independent.
Floor washdowns, equipment washing, ore desliming water,
pump seal water, and air emission scrubber water must be
completely recycled. However, since it could be physically
and economically prohibitive to separate these waters from
flotation cell water, mine water and slurry water this
condition can be met by using recycled water and not using
any fresh water for any of the former uses.
The above limitations were based on the performance achieved
at most of the existing Florida slime ponds as shown in
Section V.
A statistical analysis was performed by fitting either a
normal distribution or a log normal distribution to the
data. The best fitting distribution type was then
extrapolated to determine the level of treatment presently
achievable at a confidence level of 99 percent for the daily
and average monthly values of TSS.
It was judged that the average of all these values could not
be used since the factors controlling the variability of
effluent quality for the slime pond are beyond the practical
control of the facility operator. These factors include
wind, temperature, and aquatic growth and activity. This
last point is demonstrated by the fact that volatile
suspended solids comprised the majority of the TSS of the
final effluents. The limitations reflect the degree of
treatment achievable by properly constructed and maintained
slime ponds. Some of the facilities not achieving the
limits had insufficient data to be reliable (less than 12
data points). In fact in most cases the predicted 99
percent level of TSS was never reached The rest have
serious defects in the treatment system. For instance the
two worst discharges indicated by the table in Section V
were observed by the project officer to suffer considerable
erosion of the earthen discharge ditch walls at points prior
to the facility sample points. Other problems noted were
incorrect sampling locations and procedures. At one
facility the sample point included all untreated facility
runoff in addition to the pond discharge. At another the
sampler consistently stirred up sediment in the pipe bottom
and the reported levels of TSS were incorrectly high.
If unpredictable pond or process upsets do occur, the
present use of decant towers by the industry allows the
facility operator to cease the discharge for a sufficient
length of time in order that the suspended solids settle and
be in compliance with the discharge limitations.
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Fluoride and phosphorus will not be regulated for several
reasons. First the existing treatments are operated to
remove only suspended solids. The levels of fluoride appear
to be related in part to the well water used in the
flotation process. In addition the present fluoride
concentrations are far below the practicable level of
teatment used by related industries. It expected that a
significant portion of the phosphorus is in the form of a
suspended solid and that removal of TSS will effect removal
of phosphorus.
Although observed concentrations of radium 226 in effluents
are generally below 3 pCi/1, the potential exists for
effluent concentrations of this radionuclide to
substantially increase. These increases could be brought
about primarily by higher suspended solid levels in the
effluent or the introduction of acid to slime or effluents.
Process changes in beneficiation or differences in ore
bodies could also effect the radium 226 effluent
concentrations.	Daily fluctuations in effluent
concentration should not significantly rise above the
monthly average. Consequently, since it is costly (about
$40 per sample) to monitor for radium 226, only a monthly
average is given. Best practicable control technology
currently available for the mining and processing of
phosphate rock is clarification of waste water, recycle
insofar as possible, and exclusion of extraneous waters.
To implement this technology at facilities not already using
the recommended control techniques would require segregation
of process water from incidental water, in so far as
possible, control of other casual water, and overall good
water management practices.
All facilities sampled currently meet the radium 226 limit.
If the radium 226 concentration did exceed 5 pCi/1, barium
chloride or lime precipitation together with sulfate ion
addition could be used. Also a facility can lower radium
226 concentrations by minimizing acid entry into the process
waste water and keeping the TSS concentration low. Most of
the Florida facilities on which the guidelines were based
are presently achieving the recommended limitations using
these technologies. All western operations do or will
shortly recycle all such waters.
SULFUR (ANHYDRITE)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of process waste water pollutants.
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Mine water discharge for this subcategory is included in the
above limitations. Best practicable control technology
currently available for the mining and processing of sulfur
by the Frasch process from anhydrite deposits is the
chemical treatment and recycle of process water. Both
facilities in this subcategory are using these technologies.
SULFUR (FRASCH PROCESS SALT DOME OPERATIONS)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation
Effluent		mq/1	
Characteristic	Monthly Average Daily Maximum
TSS	50	100
sulfide	1	2
The above limitations are based on the current performance
of the 9 facilities in this subcategory.
The quantity of water used in this subcategory is
independent of the quantity of product. Therefore, effluent
limitations based on quantity of pollutant per unit of
production are not practical. Mine drainage for this
subcategory is included in the above limitations.
For facilities located in marshes that have insufficient
land to build large enough oxidation ponds to achieve the
above numbers the following limits apply.
Eff^u^nt Limitation
mg/l	~
Effluent	Monthly	Daily
Characteristic	Average	Maximum
TSS	50	100
Sulfide	5	10
If oxidation ditches are used by adding water to utilize its
dissolved oxygen content, the TSS limits are to be applied
on a net basis. There shall be no discharge of elemental
sulfur from well seal water. Best practicable control
technology currently available for the on-shore salt dome
mining and processing of sulfur by the Frasch process is the
use of oxygeneration facilities to oxidize sulfides and
ponds to reduce suspended solids. To implement this
technology at facilities not already using the recommended
control techniques would require the installation of
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adequate oxygenation equipment and settling ponds.
Discharges of sulfur in well seal water can be prevented by
careful operational control or by collection tanks. Six of
the nine facilities are presently using the recommended
technologies.
SULFUR (FRASCH PROCESS - OFF-SHORE SALT DOME OPERATIONS)
No limits on off-shore operations are proposed at this time
pending further investigation.
MINERAL PIGMENTS (IRON OXIDES)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of process generated waste water pollutants.
The mine drainage and process contaminated runoff should be
held to a daily maximum of 35 mg/1 TSS based on the data
from other subcategories. Best practicable control
technology currently available for the mining and processing
of mineral pigments (iron oxides) is the ponding and recycle
of process water when used.
To implement this technology at facilities using process
water not already using the recommended control techniques
would require the installation of settling facilities and
recycle equipment. These technologies are presently being
demonstrated by at least one major processor using process
water. This facility uses a large pond common to the
treatment of waste water from another larger production
volume product and the discharge from the pond is
attributable to the larger volume product. Two of the three
facilities studied use no process water.
LITHIUM MINERALS (SPODUMENE)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation
kg/kkg of ore processed
~ !Ibs7lOOO~lb)~
Effluent Characteristic Monthly Average Daily Maximum
TSS	0.11	0.22
fluoride	0.017	0.034
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The above limitations are based on the amount achievable by
both facilities in this subcategory. Mine drainage and
process contaminated runoff for this subcategory is included
in the above limitations. Best practicable control
technology currently available for the mining and processing
of spodumene is flocculation and settling of process water
prior to discharge. Both facilities in this subcategory are
presently utilizing the recommended technologies.
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SECTION X
EFFLUENT REDUCTION ATTAINABLE THROUGH THE
APPLICATION OF THE BEST AVAILABLE
TECHNOLOGY ECONOMICALLY ACHIEVABLE
INTRODUCTION
The effluent limitatipns which must be achieved by July 1,
1983 are based on the degree of effluent reduction attain-
able through the application of the best available tech-
nology economically achievable. For the mining of minerals
for the chemical and fertilizer industries, this level of
technology was based on the very best control and treatment
technology employed by a specific point source within each
of the industry's subcategories, or where it is readily
transferable from one industry process to another. In
Section IV, this segment of the mineral mining and proces-
sing industry was divided into twelve major categories based
on similarities of process. Several of those major
categories have been further subcategorized and, for reasons
explained in Section IV, each subcategory will be treated
separately for the recommendation of effluent limitations
guidelines and standards of performance.
The following factors were taken into consideration in
determining the best available technology economically
achievable:
(a)	the age of equipment and facilities involved;
(b)	the process employed;
(c)	the engineering aspects of the application of various
types of control techniques;
(d)	process changes;
(e)	cost of achieving the effluent reduction resulting from
application of BATEA; and
it) non-water quality environmental impact (including energy
requirements).
In contrast to the best practicable technology currently
available, best available technology economically achievable
assesses the availability in all cases of in-process
controls as well as control or additional treatment
techniques employed at the end of a production process. In-
process control options available which were considered in
establishing these control and treatment technologies
include the following:
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(1)	alternative water uses
(2)	water conservation
(3)	waste stream segregation
water reuse
(5)	cascading water uses
(6)	by-product recovery
(7)	reuse of waste water constituents
(8)	waste treatment
(9)	good housekeeping
(10)	preventive maintenance
(11)	quality control (raw material, product, effluent)
(12)	monitoring and alarm systems.
Those facility processes and control technologies which at
the pilot facility, semi-works, or other level, have
demonstrated both technological performances and economic
viability at a level sufficient to reasonably justify
investing in such facilities were also considered in
assessing the best available technology economically
achievable. Although economic factors are considered in
this development, the costs for this level of control are
intended to be for the top-of-the-line of current technology
subject to limitations imposed by economic and engineering
feasibility. However, this technology may necessitate some
industrially sponsored development work prior to its
application.
Based upon the information contained in Sections III through
IX of this report, the following determinations were made on
the degree of effluent reduction attainable with the appli-
cation of the best available control technology economically
achievable in the various subcategories of this segment of
the mineral mining and processing industry.
GENERAL WATER GUIDELINES
Process water
Process water is defined as any water contacting the ore,
processing chemicals, intermediate products, by-products or
products of a process including contact cooling water. All
process water effluents are limited to the pH range of 6.0
to 9.0 unless otherwise specified.
Cooling Water
In the mineral mining and processing industry, cooling and
process waters are sometimes mixed prior to treatment and
discharge. In other situations, cooling water is discharged
separately. Based on the application of best available
technology economically achievable, the recommendations for
the discharge of such cooling water are as follows.
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An allowed discharge of all non-contact cooling waters
provided that the following conditions are met:
(1)	Thermal pollution be in accordance with EPA standards.
Excessive thermal rise in once through non-contact
cooling water in the mineral mining and processing
industry has not been a significant problem.
(2)	All non-contact cooling waters should be monitored to
detect leaks of pollutants from the process. Provisions
should be made for treatment to the standards
established for the process waste water discharges prior
to release in the event of such leaks.
(3)	No untreated process waters be added to the cooling
waters prior to discharge.
The above non-contact cooling water recommendations should
be considered as interim, since this type of water plus
blowdowns for water treatment, boilers and cooling towers
will be regulated by EPA at a later date as a separate
category.
Storm Water Runoff
Untreated overflow may be discharged from process waste
water or mine drainage impoundments without limitation if
the impoundments are designed, constructed and operated to
contain all process generated waste water or mine drainage
and surface runoff into the impoundments resulting from a 25
year 21 hour precipitation event as established by the
National Climatic Center, National Oceanic and Atmospheric
Administration for the locality in which such impoundments
are located. To preclude unfavorable water balance
conditions resulting from precipitation and runoff in
connection with tailing impoundments, diversion ditching
should be constructed to prevent natural drainage or runoff
from mingling with process waste water or mine drainage.
PROCESS WASTEWATER GUIDELINES AND LIMITATIONS
The following industry subcategories were required to
achieve no discharge of process waste water pollutants to
navigable waters based on best practicable control tech-
nology currently available:
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barite (dry)
barite (wet) , normal opera-ting conditions
barite (flotation), normal operating conditions
fluorspar (HMS)
salines (Searles Lake)
salines (Great Salt Lake)
salines (Silver Peak)
borax
potash
trona
sodium sulfate
phosphate rock (except flotation)
sulfur (anhydrite)
mineral pigments
Best available technology economically achievable is also no
discharge of process waste water pollutants.
BARITE (WET - LOG WASHING, JIGGING AND FLOTATION)
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is the
same as BPCTCA because there are no economically achievable
methods available to reduce the suspended solids further
during periods of heavy rainfall. The mine drainage and
process contaminated runoff limits are the same as for the
best practicable control technology currently available.
FLUORSPAR (FLOTATION)
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
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Effluent Limitation
kq/kkg oF~procIuct fibs/1000 lb),
Effluent Characteristic	Monthly Average	Daily Maximum
TSS	0.4	0.8
dissolved fluoride	0.1	0.2
The above limitations are based on the anticipated
performance of treatment systems currently being installed
at one exemplary facility. The mine drainage and process
contaminated runoff limits are the same as for the best
practicable control technology currently available. Best
available technology economically achievable for the mining
and processing of fluorspar by the flotation process is good
water management, ponding in series and the use of alum to
reduce suspended solids and fluoride prior to discharge. An
alternative BATEA is ponding and evaporation where possible.
To implement this technology at facilities not already using
the recommended control techniques would require the use of
alum in treating the process waste water and adequate
settling. Two facilities are presently installing most of
the recommended technologies and will be able to meet the
prescribed limitations with the use of alum to enhance
suspended solids settling and fluoride reduction.
ROCK SALT
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
I^flHSDt_Limitation
]SS/&sg_Qf_EEoduct
ilbs/100a_lbL
Effluent Characteristic Monthly Average Dally Maxjmum
TSS	0.002	0.004
(Process and Mine Water)
Salt Storage
Pile Runoff	No discharge
The above limitations are based on the performance of at
least one facility. Salt storage pile runoff can be
eliminated by building storage silos and cones or by
covering less frequently used piles with plastic or other
fabric. Best available technology economically achievable
for the mining and processing of rock salt is the use of
drum filters, clarifiers or settling ponds to reduce
suspended solids. To implement this technology at
facilities not already using the recommended control
techniques would require the installation of any of the
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above mentioned solids/liquid separation systems. These
technologies are commonly employed in the minerals mining
and processing industry.
PHOSPHATE ROCK (FLOTATION)
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is the
same as that for best practicable control technology
currently available.
SULFUR (FRASCH PROCESS - SALT DOME OPERATIONS)
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
Effluent Limitation
Effluent	mg/l ~ _ ~
Ch^racteristic	Monthly Average Daily Maximum
TSS	30	60
sulfide	2	1
The above limitations are based on the current performance
of 5 of the 9 facilities. The quantity of water used in
this subcategory is independent of the quantity of product.
Therefore, effluent limitations based on quantity of
pollutant per unit of production are not practical. Mine
drainage for this subcategory is included in the above
limitations. Best available technology economically
achievable for the on-shore salt dome mining and processing
of sulfur by the Frasch process is improved settling to
reduce suspended solids and the use of chlorination to
eliminate sulfides. To implement this technology at
facilities not already using the recommended control
techniques would require better control of residence time in
settling ponds and the installation of chlorination
equipment. Five of the nine facilities in this subcategory
are presently meeting the recommended TSS limitation and
have eliminated sulfides from their effluents.
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LITHIUM MINERALS (SPODUMENE)
Based upon the information contained in Sections III through
IX# a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
Effluent. Limitation
kg/kkq~of ore"
processed (lbs/1000 lb)
Effluent Characteristic Monthly Average Daily Maximum
TSS	0.11	0.22
fluoride	0.008	0.016
The above limitations are based on the performance at one
facility and the projected performance of the planned treat-
ment system at the other facility. Mine drainage and
process contaminated runoff for this subcategory are
included in the above limitations. Best available
technology economically achievable for the mining and
processing of spodumene is segregation of process streams
and chemical treatment to reduce fluoride. To implement
this technology at the facility not already using the
recommended control techniques would require installation of
chemical treatment facilities and additional piping and
pumps. The one facility requiring these treatment
technologies presently has plans to implement them.
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SECTION XI
NEW SOURCE PERFORMANCE STANDARDS
AND PRETREATMENT STANDARDS
INTRODUCTION
This level of technology is -to be achieved by new sources.
The term "new source" is defined in the Act to mean "any
source, the construction of which is commenced after the
publication of proposed regulations prescribing a standard
of performance." This technology is evaluated by adding to
the consideration underlying the identification of best
available technology economically achievable, a
determination of what higher levels of pollution control are
available through the use of improved production processes
and/or treatment techniques. Thus, in addition to
considering the best in-facility and end-of-process control
technology, new source performance standards are how the
level of effluent may be reduced by changing the production
process itself. Alternative processes, operating methods of
other alternatives were considered. However, the end result
of the analysis identifies effluent standards which reflect
levels of control achievable through the use of improved
production processes (as well as control technology), rather
than prescribing a particular type of process or technology
which must be employed.
The following factors were considered with respect to
production processes which were analyzed in assessing the
best demonstrated control technology currently available for
new sources:
(a)	the type of process employed and process changes;
(b)	operating methods;
(c)	batch as opposed to continuous operations;
(d)	use of alternative raw materials and mixes of raw
materials;
(e)	use of dry rather than wet processes (including
substitution of recoverable solvents from water); and
(f)	recovery of pollutants as by-products.
In addition to the effluent limitations covering discharges
directly into waterways, the constituents of the effluent
discharge from a facility within the industrial category
which would interfere with, pass through, or otherwise be
incompatible with a well designed and operated publicly
owned activated sludge or trickling filter waste water
treatment facility were identified. A determination was
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made of whether the introduction of such pollutants into the
treatment facility should be completely prohibited.
PROCESS WATER GUIDELINES
Based upon the information contained in Sections III through
X of this report, the following determinations were made on
the degree of effluent reduction attainable with the
application of new source standards for the various
subcategories of the minerals for the chemical and
fertilizer industries segment of the mineral mining and
processing industry.
Storm Water Runoff
Untreated overflow may be discharged from process waste
water or mine drainage impoundments without limitation if
the impoundments are designed, constructed and operated to
contain all process generated waste water or mine drainage
and surface runoff into the impoundments resulting from a 25
year 24 hour precipitation event as established by the
National Climatic Center, National Oceanic and Atmospheric
Administration for the locality in which such impoundments
are located. To preclude unfavorable water balance
conditions resulting from precipitation and runoff in
connection with tailing impoundments, diversion ditching
should be constructed to prevent natural drainage or runoff
from mingling with process waste water or mine drainage.
The following industry subcategories were required to
achieve no discharge of process waste water pollutants to
navigable waters based on best practicable control tech-
nology currently available:
barite (dry)
barite (wet), normal operating conditions
barite (flotation), normal operating conditions
fluorspar (HMS)
salines (Searles Lake)
salines (Great Salt Lake)
salines (Silver Peak)
borax
potash
trona
sodium sulfate
phosphate rock (except flotation)
sulfur (anhydrite)
mineral pigments
The new source performance standards are also no discharge
of process waste water pollutants.
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The following industry subcategories are required to achieve
specific effluent limitations as given in the following
paragraphs:
BARITE (WET AND FLOTATION)
Same as best available technology economically achievable.
FLUORSPAR (FLOTATION)
Same as best available technology economically achievable.
PHOSPHATE ROCK (FLOTATION)
Same as best available technology economically achievable.
ROCK SALT
Same as best available technology economically achievable.
SULFUR (SALT DOME)
Same as best available technology economically achievable.
LITHIUM MINERALS
Same as best available technology economically achievable.
PRETREATMENT STANDARDS
Recommended pretreatment guidelines for discharge of
facility waste water into public treatment works conform in
general with EPA Pretreatment Standards for Municipal Sewer
Works as published in the July 19, 1973 Federal Register and
"Title 40 - Protection of the Environment, Chapter 1 -
Environmental Protection Agency, Subchapter D - water
Programs - Part 128 - Pretreatment Standards" a subsequent
EPA publication. The following definitions conform to these
publications:
a. Compatible Pollutant
The term "compatible pollutant" means biochemical oxygen
demand, suspended solids, pH and fecal coliform bacteria,
plus additional pollutants identified in the NPDES permit,
if the publicly-owned treatment works was designed to treat
such pollutants, and, in fact, does remove such pollutants
to a substantial degree. Examples of such additional
pollutants may include:
chemical oxygen demand
total organic carbon
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phosphorus and phosphorus compounds
ni-trogen and nitrogen compounds
fats, oils, and greases of animal or
vegetable origin except as defined
in Prohibited Wastes.
fea. Incompatible Pollutant
The term "incompatible pollutant" means any pollutant which
is not a compatible pollutant as defined above.
Joint Treatment works
Publicly owned treatment works for both non-industrial and
industrial waste water.
Major contributing Industry
A major contributing industry is an industrial user of the
publicly owned treatment works that: has a flow of 50,000
gallons or more per average work day; has a flow greater
than five percent of the flow carried by the municipal
system receiving the waste; has in its waste, a toxic
pollutant in toxic amounts as defined in standards issued
under Section 307(a) of the Act; or is found by the permit
issuance authority, in connection with the issuance of an
NPDES permit to the publicly owned treatment works receiving
the waste, to have significant impact, either singly or in
combination with other contributing industries, on that
treatment works or upon the quality of effluent from that
treatment works.
e_j_ Pretreatment
Treatment of waste waters from sources before introduction
into the joint treatment works.
Prohibited Wastes
No waste introduced into a publicly owned treatment works
shall interfere with the operation or performance of the
works. Specifically, the following wastes shall not be
introduced into the publicly owned treatment works:
(a)	Wastes which create a fire or explosion hazard in the
publicly owned treatment works;
(b)	Wastes which will cause corrosive structural damage to
treatment works, but in no case wastes with a pH lower
than 5.0, unless the works are designed to accommodate
such wastes;
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(c)	Solid or viscous wastes in amounts which would cause
obstruction to the flow in sewers, or other interference
with the proper operation of the publicly-owned
treatment works, and
(d)	Wastes at a flow rate and/or pollutant discharge rate
which is excessive over relatively short time periods so
that there is a treatment process upset and subsequent
loss of treatment efficiency.
Recommended Pretreatment Guidelines
In accordance with the preceding Pretreatment Standards for
Municipal Sewer Works, the following are recommended for
Pretreatment Guidelines for the waste water effluents:
(a)	No pretreatment required for removal of compatible
pollutants - biochemical oxygen demand, suspended solids
(unless hazardous), pH, and fecal coliform bacteria;
(b)	Suspended solids containing hazardous pollutants such as
heavy metals, cyanides and chromates should conform to
be restricted to those quantities recommended for the
best practicable control technology currently available
for existing sources and for new source performance
standards for new sources.
(c)	Pollutants such as chemical oxygen demand, total organic
carbon, phosphorus and phosphorus compounds, nitrogen
and nitrogen compounds, and fats, oils, and greases,
need not be removed provided the publicly owned
treatment works was designed to treat such pollutants
and will accept them. Otherwise levels should be at or
below the best practicable control technology currently
available for existing sources and for new source
performance standards for new sources.
(d)	Limitations on dissolved solids is not recommended
except in case of water quality violations.
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SECTION XII
ACKNOWLEDGEMENTS
The preparation of this report was accomplished through the
efforts of the staff of General Technologies Division,
Versar, Inc., Springfield, Virginia, under the overall
direction of Dr. Robert G. Shaver, Vice President. Mr.
Robert C. Smith, Jr., Chief Engineer, Project Office,
directed the day-to-day work on the program.
Mr. Michael w. Kosakowski was the Project Officer. Mr.
Allen Cywin, Director, Effluent Guidelines Division, Mr.
Ernst P. Hall, Jr., Assistant Director, Effluent Guidelines
Division, and Mr. Harold B. Coughlin, Chief, Guidelines
Implementation Branch, offered many helpful suggestions
during the program. Mr. Ralph Lorenzetti assisted with many
facility inspections.
Acknowledgement and appreciation is also given to Linda Rose
and Darlene Miller the word processing/editorial assistant
staff of the Effluent Guidelines Division and the
secretarial staff of the General Technologies Division of
Versar, Inc., for their efforts in the typing of drafts,
necessary revisions, and final preparation of the effluent
guidelines document.
Appreciation is extended to the following trade associations
and state and federal agencies for assistance and
cooperation rendered to us in this program:
American Mining Congress
Asbestos Information Association, Washington, D.C.
Barre Granite Association
Brick Institute of America
Building Stone Institute
Fertilizer Institute
Florida Limerock Institute, Inc.
Florida Phosphate Council
Georgia Association of Mineral Processing Industries
Gypsum Association
Indiana Limestone Institute
Louisiana Fish and wildlife Commission
Louisiana Water Pollution Control Board
Marble Institute of America
National Clay Pipe Institute
National Crushed Stone Association
National Industrial Sand Association
National Limestone Institute
265

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National Sand and Gravel Association
New York State Department of Environmental conservation
North Carolina Minerals Association
North Carolina Sand, Gravel and Crushed Stone Association
Portland Cement Association
Refractories Institute
Salt Institute
State of Indiana Geological Survey
Texas Water Quality Board
U.S. Bureau of Mines
U.S. Fish and Wildlife Service, Lacrosse, Wisconsin
Vermont Department of Water Resources
Appreciation is also extended to the many mineral mining and
producing companies who gave invaluable assistance and
cooperation in this program.
Also, appreciation is extended to the individuals of the
staff of General Technologies Division of Versar, Inc., for
their assistance during this program. Specifically, our
thanks to:
Dr. R. L. Durfee, senior Chemical Engineer
Mr. D. H. Sargent, Senior Chemical Engineer
Mr. E. F. Abrams, Chief Engineer
Mr. L. C. McCandless, Senior Chemical Engineer
Dr. L. C. Parker, senior Chemical Engineer
Mr. E. F. Rissman, Environmental Scientist
Mr. J. C. Walker, Chemical Engineer
Mrs. G. Contos, Chemical Engineer
Mr. M. W. Slimak, Environmental Scientist
Dr. I. Frankel, Chemical Engineer
Mr. M. DeFries, Chemical Engineer
Ms. C. V. Fong, Chemist
Mrs. D. K. Guinan, Chemist
Mr. J. G. Casana, Environmental Engineer
Mr. R. C. Green, Environmental Scientist
Mr. R. S. Wetzel, Environmental Engineer
Ms. M.A. Connole, Biological Scientist
Ms. M. Smith, Analytical Chemist
Mr. M. C. Calhoun, Field Engineer
Mr. D. McNeese, Field Engineer
Mr. E. Hoban, Field Engineer
Mr. P. Nowacek, Field Engineer
Mr. B. Ryan, Field Engineer
Mr. R. Freed, Field Engineer
Mr. N. 0. Johnson, Consultant
Mr. F. Shay, Consultant
Dr. L. W. Ross, Chemical Engineer
Mr. J. Boyer, Chemical Engineer
266

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SECTION XIII
REFERENCES
1.	Agnello, L., "Kaolin", Industrial and Engineering
Chemistry,Vol. 52, No. 5, May 1960, pp. 370-376.
2.	"American Ceramic Society Bulletin," Vol. 53, No. 1,
January 1974, Columbus, Ohio.
3.	Arndt, R.H., "The Shell Dredging Industry of the Gulf
Coast Region," U.S. Department of the Interior, 1971.
4.	Bates, R.L., Geology of the Industrial Rocks and
Minerals,Dover Publications,~Inc., New York, 19697
5.	Beeghly, J.H., "Water Quality and the Sand and Gravel
Industry," 37th Annual Meeting Ohio Sand and Gravel
Association, 1971.
6.	Black and Veatch, Consulting Engineers, "Process Design
Manual for Phosphorus Removal," U.S. EPA Program 17010
GNP Contract 14-12-936, October, 1971.
7.	Boruff, C.S., "Removal of Fluorides from Drinking
Waters," Industrial and Engineering Chemistry. Vol. 26,
No. 1, January 1934, pp. 69-71.
8.	Brooks, R.G., "Dewatering of Solids," 57th Annual
Convention National Crushed Stone Association, 1974.
9.	Brown, W.E., U.S. Patent 2,761,835, September 1956.
10.	Brown, W.E., and Gracobine, C.R., U.S. Patent 2,761,841,
September 1956.
11.	"Census of Minerals Industries," 1972, Bureau of the
Census, U.S. Department of Commerce, U.S. Government
Printing Office, Washington, D.C. MIC72(P)-14A-1 through
MIC7 2(P)-14E-4.
12.	"Commodity Data Summaries, 1974, Appendix I to Mining
and Minerals Policy," Bureau of Mines, U.S. Department
of the Interior, U.S. Government Printing Office,
Washington, D.C.
13.	Davison, E.K., "Present Status of Water Pollution
Control Laws and Regulations," 57th Annual Convention
National Sand and Gravel Association, 1973.
267

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14.	Day, R.W., "The Hydrocyclone in Process and Pollution
Control," Chemical Engineering Progress. Vol. 69, No. 9,
1973,	pp. 67-72.
15.	"Dictionary of Mining, Mineral, and Related Terms,"
Bureau of Mines, U.S. Department of the Interior, U.S.
Government Printing Office, Washington, D.C., 1968.
16.	"Engineering and Mining Journal," McGraw-Hill, October
1974.
17.	Groom, F., "Vacuum Filtration - An Alternative to the
Use of Large Settling Ponds in Sand and Gravel
Production," National Sand and Gravel Association
Circular No. 117.
18.	Haden, W., Jr., and Schwint, I., "Attapulgite, Its
Properties and Applications," Industrial and Engineering
Chemistry. Vol. 59, No. 9, September "?967, pp7 57-697"
19.	Huffstuter, K.K., Slack, A.V., Phosphoric Acid. Vol. 1,
Part 2, Marcel Dekker, Inc., N.Y.7 1968."
20.	"Indiana Limestone Handbook," Indiana Limestone
Institute of America, Inc., January 1973, Bedford,
Indiana.
21.	Krenkel, P.A., "Principles of Sedimentation and
Coagulation As Applied to the Clarification of Sand and
Gravel Process Water," National Sand and Gravel
Association Circular No. 118.
22.	Levine, s., "Liquid/Solids Separation Via Wet
Classification," Rock Products. September 1972, pp.
84-95.
23.	Little, A.D., "Economic Impact Analysis of New Source
Air Quality standards on the Crushed Stone Industry,"
EPA Draft Report, 1974.
24.	Llewellyn, C.M., "The Use of Flocculants in the James
River Estuary," Miscellaneous Paper, Lone Star
Industries.
25.	Llewellyn, C.M., "Maintenance of Closed Circuit Water
Systems," National Crushed stone Association Meeting,
Charlotte, N.C., 1973.
26.	Locke, S.R., Ozal, M.A., Gray, J., Jackson, R.E., and
Preis, A., "Study to Determine the Feasibility of an
Experiment to Transfer Technology to the Crushed stone
.268

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Industry," Martin Marietta Laboratories, NSF Contract
C826, 1974.
27.	Maier, F.J., "Defluoridation of Municipal Water
Supplies," Journal AWWA, August 1953, pp. 879-888.
28.	May, E.B., "Environmental Effects of Hydraulic Dredging
in Estuaries," Alabama Marine Resources Bulletin No. 9,
April 1973, pp. 1-85.
29.	McNeal, W., and Nielsen, G., "International Directory of
Mining and Mineral Processing Operations," E/MJ,
McGraw-Hill, 1973-1974.
30.	"Minerals Yearbook, Metals, Minerals, and Fuels,
Vol. 1," U.S. Department of the Interior, U.S.
Government Printing Office, Washington, D.C., 1971,
1972.
31.	"Mining Engineering, Publication of the Society of
Mining Engineers of AIME, Annual Review for 1973," Vol.
25, No. 1, January 1973; Vol. 26, No. 3, March 1974
through Vol. 26, No. 8, August 1974.
32.	"Modern Mineral Processing Flowsheets," Denver Equipment
Company, 2nd Ed., Denver, Colorado
33.	Monroe, R.G., "Wastewater Treatment Studies in Aggregate
and Concrete Production," EPA Technology Series
EPA-R2-73-003, 1973.
34.	Newport, B.D., and Moyer, J.E., "State-of-the-Art: Sand
and Gravel Industry," EPA Technology Series
EPA-660/2-74-066, 1974.
35.	Oleszkiewicz, J.A., and Krenkel, P.A., "Effects of Sand
and Gravel Dredging in the Ohio River," Vanderbilt
University Technical Report No. 29, 1972.
36.	Patton, T.C., "Silica, Microcrystalline," Pigment
Handbook Voi^ 1, J. Wiley and Sons, Inc., 1973, pp.
"157-159.
37.	popper, H., Modern Engineering Cost Techniques,
McGraw-Hill, New YorkT 1970. ~	~~
38.	"Phosphorus Derived Chemicals," U.S. EPA,
EPA-440/1-74-006-a, Washington, D.C., January, 1974.
39.	Price, W.L., "Dravo Dredge No. 16," National Sand and
Gravel Association Circular No. 82, 1960.
269

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40.	"Product Directory of the Refractories Industry in the
U.S.," The Refractories Institute, Pittsburgh, Pa. 197 2.
41.	"Radiochemical Pollution from Phosphate Rock Mining and
Milling," National Field Investigations Center, Denver,
EPA, Denver, Colorado, December, 1973.
42.	Resource Consultants, Inc., Engineering Report,
"Wastewater Treatment for Dixie Sand and Gravel Co.,"
Chattanooga, Tenn., 1972.
43.	Robertson, J.L., "Washer/Classifier System Solves clay
Problem at Sand and Gravel Facility," Rock Products.
March 1973, pp. 50-53.
44.	Slabaugh, W.H., and Culbertsen, J.L., J. Ph^s. Chem.,55,
744, 1951.
45.	Smith, C.A., "Pollution Control Through Waste Fines
Recovery," National Sand and Gravel Association Circular
No. 110.
46.	State Directories of the Mineral Mining Industry from 36
of 50 States.
47.	Trauffer, W.E., "New Vermont Talc Facility Makes
High-Grade Flotation Product for Special Uses," Pit and
Quarry.December 1964, pp. 72-74, 101.	~~
48.	Walker, S., "Production of Sand and Gravel,"	Amer.
Concrete Inst.,, Vol. 26, No. 2, 1954, pp. 165-178.
49.	Williams, F.J., Nezmayko, M., and weintsitt, D.J., J.
Phvsf Chem., 57, 8, 1953.
270

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SECTION XIV
GLOSSARY
Aeration - the introduction of air into the pulp in a
flotation cell in order to form air bubbles.
Aquifer - an underground stratum that yields water.
Baghouse - chamber in which exit gases are filtered through
membranes (bags) which arrest solids.
Bench - a ledge, which, in open pit mines and quarries,
forms a single level of operation above which mineral or
waste materials are excavated from a contiguous bank or
bench face.
Berm - a horizontal shelf built for the purpose of
strengthening and increasing the stability of a slope or
to catch or arrest slope slough material; berm is
sometimes used as a synonym for bench.
Blunge - to mix thoroughly.
Burden - valueless material overlying the ore.
Cell, cleaner - secondary cells for the retreatment of the
concentrate from primary cells.
Cell, rougher - flotation cells in which the bulk of the
gangue is removed from the ore.
Clarifier - a centrifuge, settling tank, or other device,
for separating suspended solid matter from a liquid.
Classifier, air - an appliance for approximately sizing
crushed minerals or ores employing currents of air.
Classifier, rake - a mechanical classifier utilizing
reciprocal rakes on an inclined plane to separate coarse
from fine material contained in a water pulp.
Classifier, spiral - a classifier for separating fine-size
solids from coarser solids in a wet pulp consisting of
an interrupted-flight screw conveyor, operating in an
inclined trough.
271

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Collector - a heteropolar compound chosen for its ability to
adsorb selectively in froth flotation and render the
adsorbing surface relatively hydrophobic.
Conditioner - an apparatus in which the surfaces of the
mineral species present in a pulp are treated with
appropriate chemicals to influence their reaction during
aeration.
Crusher, cone - a machine for reducing the size of materials
by means of a truncated cone revolving on its vertical
axis within an outer chamber, the anular space between
the outer chamber and cone being tapered.
Crusher, gyratory - a primary crusher consisting of a
vertical spindle, the foot of which is mounted in an
eccentric bearing within a conical shell. The top
carries a conical crushing head revolving eccentrically
in a conical maw.
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.
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. Rock is
fed in from above and nipped between the moving rolls,
crushed, and discharged below.
Depressant - a chemical which causes substances to sink
through a froth, in froth flotation.
Dispersant - a substance (as a polyphosphate) for promoting
the formation and stabilization of a dispersion of one
substance in another.
Dragline - a type of excavating equipment which employs a
rope-hung bucket to dig up and collect the material.
Dredge, bucket - a two-pontooned dredge from which are
suspended buckets which excavate material at the bottom
of the pond and deposit it in concentrating devices on
the dredge decks.
Dredge, suction - a centrifugal pump mounted on a barge.
Drill, churn - a drilling rig utilizing a blunt-edged chisel
bit suspended from a cable for putting down vertical
holes in exploration and quarry blasting.
272

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Drill, diamond - a drilling machine with a rotating, hollow,
diamond-studded bit that cuts a circular channel around
a core which when recovered provides a columnar sample
of the rock penetrated.
Drill, rotary - various types of drill machines that rotate
a rigid, tubular string of rods to which is attached a
bit for cutting rock to produce boreholes.
Dryer, flash - an appliance in which the moist material is
fed into a column of upward-flowing hot gases with
moisture removal being virtually instantaneous.
Dryer, fluidized bed - a cool dryer which depends on a mass
of particles being fluidized by passing a stream of hot
air through it. As a result of the fluidization,
intense turbulence is created in the mass including a
rapid drying action.
Dryer, rotary - a dryer in the shape of an inclined rotating
tube used to dry loose material as it rolls through.
Electrostatic separator - a vessel fitted with positively
and negatively charged conductors used for extracting
dust from flue gas or for separating mineral dust from
gangues.
Filter, pressure - a machine utilizing pressure to increase
the removal rate of solids from tailings.
Filter, vacuum - a filter in which the air beneath the
filtering material is exhausted to hasten the process.
Flocculant - an agent that induces or promotes gathering of
suspended particles into aggregations.
Flotation - the method of mineral separation in which a
froth created in water by a variety of reagents floats
some finely crushed minerals, whereas other minerals
sink.
Frother - substances used in flotation to make air bubbles
sufficiently permanent, principally by reducing surface
tension.
Grizzly - a device for the coarse screening or scalping of
bulk materials.
Hydraulic Mining - mining by washing sand and dirt away with
water which leaves the desired mineral.
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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.
Humphrey spiral - a concentrating device which exploits
differential densities of mixed sands by a combination
of sluicing and centrifugal action. The ore pulp
gravitates down through a stationary spiral trough with
five turns. Heavy particles stay on the inside and the
lightest ones climb to the outside.
Jigging - process used to separate coarse materials in the
ore by means of differences in specific gravity in a
water medium.
Jumbo - a drill carriage on which several drills are
mounted.
Kiln, rotary - a kiln in the form of a long cylinder,
usually inclined, and slowly rotated about its axis; the
kiln is fired by a burner set axially at its lower end.
Kiln, tunnel - a long tunnel-shaped furnace through which
ware is generally moved on cars, passing progressively
through zones in which the temperature is maintained for
preheating, firing and cooling.
Launder - a chute or trough for conveying powdered ore, or
for carrying water to or from the crushing apparatus.
Log washer - a slightly slanting trough in which revolves a
thick shaft or log, earring blades obliquely set to the
axis. Ore is fed in at the lower end, water at the
upper. The blades slowly convey the lumps of ore upward
against the current, while any adhering clay is
gradually disintegrated and floated out the lower end.
Magnetic separator - a device used to separate magnetic from
less magnetic or nonmagnetic materials.
mgd - million gallons per day
Mill, ball - a rotating horizontal cylinder in which non-
metallic materials are ground using various types of
grinding media such as quartz pebbles, porcelain balls,
etc.
Mill, buhr - a stone disk mill, with an upper horizontal
disk rotating above a fixed lower one.
274

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Mill, chaser - a cylindrical steel -tank lined with wooden
rollers revolving 15-30 times a minute.
Mill, hammer - an impact mill consisting of a rotor, fitted
with movable hammers, that is revolved rapidly in a
vertical plane within a closely fitting steel casing.
Mill, pebble - horizontally mounted cylindrical mill,
charged with flints or selected lumps of ore or rock.
Mill, rod - a mill for fine grinding, somewhat similar to a
ball mill, but employing long steel rods instead of
balls to effect the grinding.
Mill, roller - a fine grinding mill having vertical rollers
running in a circular enclosure with a stone or iron
base.
Neutralization - making neutral or inert, as by the addition
of an alkali or an acid solution.
Outcrop - the part of a rock formation that appears at the
surface of the ground or deposits that are so near to
the surface as to be found easily by digging.
Overburden - material of any nature, consolidated or
unconsolidated, that overlies a deposit of useful
materials, ores, etc.
Permeability - capacity for transmitting a fluid.
Raise - an inclined opening driven upward from a level to
connect with the level above or to explore the ground
for a limited distance above one level.
Reserve - known ore bodies that may be worked at some future
time.
Ripper - a tractor accessory used to loosen compacted soils
and soft rocks for scraper loading.
Room and Pillar - la system of mining in which the
distinguishing feature is the winning of 50 percent or
more of the ore in the first working. The ore is mined
in rooms separated by narrow ribs (pillars); the ore in
the pillars is won by subsequent working in which the
roof is caved in successive blocks.
Scraper - a tractor-driven surface vehicle the bottom of
which is fitted with a cutting blade which when lowered
is dragged through the soil.
275

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Scrubber, dust - special apparatus used to remove dust from
air by washing.
Scrubber, ore - device in which coarse and sticky ore is
washed free of adherent material, or mildly
disintegrated.
Shuttle-car - a vehicle which transports raw materials from
loading machines in trackless areas of a mine to the
main transportation system.
Sink-float - processes that separate particles of different
sizes or composition on the basis of specific gravity.
Skip - a guided steel hoppit used in vertical or inclined
shafts for hoisting mineral.
Slimes - extremely fine particles derived from ore,
associated rock, clay or altered rock.
Sluice - to cause water to flow at high velocities for
wastage, for purposes of excavation, ejecting debris,
etc.
Slurry - pulp not thick enough to consolidate as a sludge
but sufficiently dewatered to flow viscously.
Stacker - a conveyor adapted to piling or stacking bulk
materials or objects.
Stope - an excavation from which ore has been excavated in a
series of steps.
Stripping ratio - the unit amount of spoil that must be
removed to gain access to a similar unit amount of ore
or mineral material.
Sump - any excavation in a mine for the collection of water
for pumping.
Table, air - a vibrating, porous table using air currents to
effect gravity concentration of sands.
Table, wet - a concentration process whereby a separation of
minerals is effected by flowing a pulp across a riffled
plane surface inclined slightly from the horizontal,
differentially shaken in the direction of the long axis
and washed with an even flow of water at right angles to
the direction of motion.
276

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TDS Total dissolved solids
Thickener - an apparatus for reducing the proportion of
water in a pulp.
TKN - Total kylldahl nitrogen.
TSS - Total suspended solids.
Waste - the barren rock in a mine or the part of the ore
deposit that is too low in grade to be of economic value
at the time.
Water, connate - water that was deposited simultaneously
with the solid sediments, and which has not, since its
deposition, existed as surface water or as atmospheric
moisture.
Weir - an obstruction placed across a stream for the purpose
of channeling the water through a notch or an opening in
the weir itself.
Wire saw - a saw consisting of one- and three-strand wire
cables, running over pulleys as a belt. When fed by a
slurry of sand and water and held against rock by
tension, it cuts a narrow channel by abrasion, many
facility inspections.
277

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TABLE 25
METRIC UNITS
CONVERSION TABLE
Multiply (English Units)	by	To obtain (Metric units)
ENGLISH UNIT
ABBREVIATION
CONVERSION
ABBREVIATION
METRIC UNIT
acre
a c
0.405
ha
hectares
acre - feet
ac ft
1233.5
cu m
cubic meters
British Thermal Unit
BTU
0.252
kg cal
kilogram - calories
British Thermal Unit/




pound
BTU/lb
0.555
kg cal/kg
kilogram calories/kilogram
cubic feet/minute
cfm
0.028
cu rr/min
cubic meters/minute
cubic feet/second
cfs
1.7
cu nv'min
cubic meters/mi nute
cubic feet
cu ft
0.028
cu m
cubic meters
cubic feet
cu ft
23.32
1
liters
cubic inches
cu in
16.39
cu cm
cubic centimeters
degree Fahrenheit
F°
0.555 (°F-32)*
°C
degree Centigrade
feet
ft
0.3048
m
meters
gallon
gal
3.735
1
liters
gallon/minute
gpm
0.0631
l/sec
liters/second
horsepower
hp
0.7457
kw
killowatts
inches
in
2.54
cm
centimeters
inches of mercury
in Hg
0.03342
atm
atmospheres
pounds
lb
0.454
kg
kilograms
mi i lion ga 1 Ions/day
mgd
3,785
cu nv^day
cubic meters/day
mile
mi
1.609
km
kilometer
pound/square inch




(gauge)
psig
(0.06805 psig +1)*
atm
atmospheres (absolute)
square feet
sq ft
0.0929
sq m
square meters
square inches
sq in
6.452
sq cm
square centimeters
tons (short)
t
0.907
kkg
metric tons (1000 kiiograrrs)
yard
y
0.9144
m
meters
•Actual conversion, not a multiplier

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