&EPA
United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
March 1979
Air
Non-Metallic Mineral
Processing Plants -
Background
Information
for Proposed
Emission Standards
Draft
EIS
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Non-Metal lie Mineral Processing Plants
Background Information
for Proposed Standards
Emission Standards and Engineering Division
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air, Noise, and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
March 1979
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This report is issued by the Environmental Protection Agency to report technical
data of interest to a limited number of readers. Copies are available - in
limited quantities - from the Library Services Office (MD-35), U.S. Environ-
mental Protection Agency, Research Triangle Park, North Carolina 27711; or,
for a fee, from the National Technical Information Service, 5285 Port Royal
Road, Springfield, Virginia 22161.
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Background Information
and Draft
Environmental Impact Statement
for
Non-Metallic Mineral Processing Plants
Type of Action : Administrative
Prepared by:
Don R. Goodwin
Director, Emission Standards and Engineering Division
Environmental Protection Agency
Research Triangle Park, N.C. 27711
Approved by:
David G. Hawkins
Assistant Administrator for Air, Noise and Radiation
Environmental Protection Agency
Washington, D. C. 20460
Draft Statement Submitted to EPA's
Office of Federal Activities for Review on
This document may be reviewed at:
Central Docket
Room 2903B, Waterside Mall
Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
Additional copies may be obtained at:
Environmental Protection Agency Library (MD-35)
Research Triangle Park, N. C. 27711
National Technical Information Service
5285 Port Royal Road
Springfield, Virginia 22161
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TABLE OF CONTENTS
Page
LIST OF FIGURES V11
LIST OF TABLES 1X
CHAPTER 1. SUMMARY 1'1
1.1 PROPOSED STANDARDS 1-1
•1.2 ENVIRONMENTAL IMPACT !-2
1.3 ECONOMIC IMPACT ]-5
1.4 INFLATION IMPACT ]-6
CHAPTER 2. INTRODUCTION 2-"1
2.1 AUTHORITY FOR THE STANDARDS 2-1
2.2 SELECTION OF CATEGORIES OF STATIONARY SOURCES 2-6
2.3 PROCEDURE FOR DEVELOPMENT OF STANDARDS OF PERFORMANCE 2-8
2.4 CONSIDERATION OF COSTS 2-11
2.5 CONSIDERATION OF ENVIRONMENTAL IMPACTS 2-12
2.6 IMPACT ON EXISTING SOURCES 2-14
2.7 REVISION OF STANDARDS OF PERFORMANCE 2-15
CHAPTER 3. THE NON-METALLIC MINERALS INDUSTRY 3-1
3.1 GENERAL 3-1
3.2 NON-METALLIC MINERALS PREPARATION PROCESSES AND THEIR EMISSIONS 3-12
3.3 REFERENCES 3-53
CHAPTER 4. EMISSION CONTROL TECHNIQUES 4-1
4.1 CONTROL OF PLANT PROCESS OPERATIONS 4-1
4.2 FACTORS AFFECTING THE PERFORMANCE OF CONTROL METHODS 4-29
4.3 PERFORMANCE OF PARTICULATE EMISSION CONTROL TECHNIQUES .... 4-32
4.4 REFERENCES 4-46
iv
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TABLE OF CONTENTS (continued)
Page
CHAPTER 5. MODIFICATION AND RECONSTRUCTION 5-1
5.1 APPLICABILITY TO NON-METALLIC MINERALS PROCESSING PLANTS ... 5-1
CHAPTER 6. EMISSION CONTROL SYSTEMS 6-1
CHAPTER 7. ENVIRONMENTAL IMPACT 7-1
7.1 AIR POLLUTION IMPACT 7-1
7.2 WATER POLLUTION IMPACT 7-18
7.3 SOLID WASTE DISPOSAL IMPACT 7-18
7.4 ENERGY IMPACT 7-19
7.5 NOISE IMPACT 7-23
7.6 REFERENCES 7-25
CHAPTER 8. ECONOMIC IMPACT 8-1
8.0 SUMMARY 8-1
8.1 UNITED STATES NON-METALLIC MINERALS INDUSTRY STRUCTURE .... 8-4
8.2 COST ANALYSIS OF ALTERNATIVE EMISSION CONTROL SYSTEMS 8-55
8.3 OTHER COST CONSIDERATIONS 8-89
8.4 ECONOMIC IMPACT ASSESSMENT 8-93
8.5 POTENTIAL SOCIO-ECONOMIC AND INFLATIONARY IMPACTS 8-122
CHAPTER 9. RATIONALE 9-1
9.1 SELECTION OF SOURCE FOR CONTROL 9-1
9.2 SELECTION OF POLLUTANT AND AFFECTED FACILITIES 9-2
9.3 SELECTION OF THE BEST SYSTEM OF EMISSION REDUCTION 9-5
9.4 SELECTION OF FORMAT FOR THE PROPOSED STANDARDS 9-12
9.5 SELECTION OF EMISSION LIMITS 9-14
9.6 SELECTION OF PERFORMANCE TEST METHODS 9-18
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TABLE OF CONTENTS (continued)
Page
APPENDIX A. EVOLUTION OF THE PROPOSED STANDARDS A-l
APPENDIX B. INDEX TO ENVIRONMENTAL IMPACT CONSIDERATIONS B-1
APPENDIX C. SUMMARY OF TEST DATA C-l
APPENDIX D. EMISSION MEASUREMENT AND CONTINUOUS MONITORING D-l
D.I EMISSION MEASUREMENT METHODS D-l
D.2 MONITORING SYSTEMS AND DEVICES D-2
D.3 PERFORMANCE TEST METHODS D-2
APPENDIX E. ENFORCEMENT ASPECTS E-l
E.I PROCESS OPERATION E-l
E.2 DETERMINATION OF COMPLIANCE WITH THE CONCENTRATION STANDARD . . E-2
E.3 DETERMINATION OF COMPLIANCE WITH VISIBLE EMISSION STANDARDS . . E-3
E.4 EMISSION MONITORING REQUIREMENTS . E-4
VI
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LIST OF FIGURES
Page
Figure 3-1 FLOWSHEET OF A TYPICAL CRUSHING PLANT 3-14
Figure 3-2 GENERAL SCHEMATIC FOR NON-METALLIC MINERALS PROCESSING . . 3-18
Figure 3-3 DOUBLE-TOGGLE JAW CRUSHER 3-26
Figure 3-4 SINGLE-TOGGLE JAW CRUSHER 3-26
Figure 3-5 THE PIVOTED SPINDLE GYRATORY 3-29
Figure 3-6 CONE CRUSHER 3-29
Figure 3-7 DOUBLE-ROLL CRUSHER 3-31
Figure 3-8 SINGLE ROLL CRUSHER 3-31
Figure 3-9 HAMMERMILL 3-33
Figure 3-10 IMPACT CRUSHER 3-33
Figure 3-11 VIBRATING GRIZZLY 3-37
Figure 3-12 VIBRATING SCREEN 3-37
Figure 3-13 CONVEYOR BELT TRANSFER POINT 3-40
Figure 3-14 BUCKET ELEVATOR TYPES 3-42
Figure 3-15 ROLLER MILL 3-47
Figure 3-16 BALL MILL 3-49
Figure 3-17 FLUID-ENERGY MILL 3-49
Figure 4-1 WET DUST SUPPRESSION SYSTEM 4-7
Figure 4-2 DUST SUPPRESSION APPLICATION AT CRUSHER DISCHARGE 4-9
Figure 4-3 HOOD CONFIGURATION USED TO CONTROL A CONE CRUSHER ...... 4-14
Figure 4-4 HOOD CONFIGURATION FOR VIBRATING SCREEN 4-15
Figure 4-5 HOOD CONFIGURATION FOR CONVEYOR TRANSFER, LESS THAN
0.91 METER (3-FOOT) FALL 4-17
Figure 4-6 HOOD CONFIGURATION FOR A CHUTE TO BELT OR CONVEYOR TRANSFER,
GREATER THAN 0.01 METERS (3-FOOT) FALL 4-18
vii
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LIST OF FIGURES (continued)
Page
Figure 4-7 EXHAUST CONFIGURATION AT BIN OR HOPPER 4-19
Figure 4-8 BAG FILLING VENT SYSTEM 4-20
Figure 4-9 TYPICAL BAGHOUSE OPERATION . 4-23
Figure 4-10 BAGHOUSE CLEANING METHODS 4-25
Figure 4-11 MECHANICAL, CENTRIFUGAL SCRUBBER 4-28
Figure 4-12 TYPICAL COMBINATION DUST CONTROL SYSTEMS 4-30
Figure 4-13 PARTICULATE EMISSIONS FROM NON-METALLIC MINERALS
PROCESSING OPERATIONS 4-35
Figure 7-1 PLANT LAYOUTS SHOWING THE NUMBER AND LOCATIONS OF THE
SOURCES (STACKS) SPECIFIED FOR EACH PLANT SIZE 7-9
Figure 8-1 COST-EFFECTIVENESS OF ALTERNATIVE CONTROL SYSTEMS 8-84
Figure 8-2 INSTALLED COSTS OF FABRIC FILTER SYSTEMS 8-87
vm
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LIST OF TABLES
Page
Table 1-1 MATRIX OF ENVIRONMENTAL AND ECONOMIC IMPACTS OF
ALTERNATIVE STANDARDS 1-4
Table 3-1 INDUSTRY CHARACTERISTICS 3-3
Table 3-2 MAJOR USES OF THE NON-METALLIC MINERALS 3-6
Table 3-3 POSSIBLE SOURCES OF EMISSIONS 3-16
Table 3-4 EMISSION SOURCES AT NON-METALLIC MINERAL FACILITIES 3-17
Table 3-5 PARTICULATE EMISSION FACTORS FOR STONE CRUSHING PROCESS . . .3-19
Table 3-6 RELATIVE CRUSHING MECHANISMS UTILIZED BY VARIOUS CRUSHERS . .3-24
Table 3-7 APPROXIMATE CAPACITIES OF JAW CRUSHERS 3-27
Table 3-8 APPROXIMATE CAPACITIES OF GYRATORY CRUSHERS 3-27
Table 3-9 PERFORMANCE DATA FOR CONE CRUSHERS 3-30
Table 4-1 PARTICULATE EMISSION SOURCES FOR THE EXTRACTION AND
PROCESSING OF NON-METALLIC MINERALS 4-2
Table 4-2 BAGHOUSE UNITS TESTED BY EPA 4-34
Table 4-3 AIR-TO-CLOTH RATIOS FOR FABRIC FILTERS USED FOR EXHAUST
EMISSION CONTROL 4-38
Table 4-4 SUMMARY OF VISIBLE EMISSIONS MEASUREMENTS FROM FUGITIVE
SOURCES AT NON-METALLIC MINERALS PLANTS 4-42
Table 6-1 MODEL PLANTS FOR ESTIMATING ENVIRONMENTAL AND ECONOMIC
IMPACT 6-2
Table 6-2 LIST OF PROCESS EQUIPMENT INCLUDING ENERGY REQUIREMENTS
AND AIR VOLUME REQUIREMENTS USED IN DETERMINING MODEL
PLANTS 6-4
Table 6-3 PLANT SIZES FOR THE VARIOUS NON-METALLIC MINERALS INDUSTRIES
(METRIC UNITS) 6-6
Table 7-1 ALLOWABLE EMISSIONS UNDER GENERAL STATE PROCESS WEIGHT
REGULATIONS 7-2
Table 7-2 GROWTH RATES AND MINERAL PRODUCTION LEVELS FOR THE VARIOUS
NON-METALLIC MINERALS INDUSTRIES 7-3
Table 7-3 SUMMARY OF AIR POLLUTION IMPACT 7-5
Table 7-4 STACK AND EMISSIONS DATA 7-11
ix
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Table 7-5
Table 7-6
Table 7-7
Table 7-8
Table 7-9
Table 8-1
Table 8-2
Table 8-3
Table 8-4
Table 8-5
Table 8-6
Table 8-7
Table 8-8
Table 8-9
Table 8-10
Table 8-11
Table 8-12
Table 8-13
Table 8-14
Table 8-15
LIST OF TABLES (continued)
ESTIMATED MAXIMUM 24-HOUR AND ANNUAL GROUND-LEVEL PARTICU-
LATE CONCENTRATION DUE TO EMISSIONS FROM THE PROCESS
SOURCES IN THE MODEL NON-METALLIC MINERALS PLANTS HAVING
BOTH CRUSHING AND GRINDING OPERATIONS
Page.
7-15
ESTIMATED MAXIMUM 24-HOUR AND ANNUAL GROUND-LEVEL PARTICU-
LATE CONCENTRATION DUE TO EMISSIONS FROM THE PROCESS
SOURCES IN THE MODEL NON-METALLIC MINERALS PLANTS HAVING
ONLY CRUSHING OPERATIONS
ENERGY REQUIREMENTS FOR MODEL NON-METALLIC MINERALS PLANTS
HAVING CRUSHING AND GRINDING OPERATIONS
ENERGY REQUIREMENTS FOR MODEL NON-METALLIC MINERALS PLANTS
HAVING CRUSHING OPERATIONS ONLY
ENERGY IMPACT ON INDIVIDUAL NON-METALLIC INDUSTRIES UNDER
PROPOSED NSPS
SAND AND GRAVEL: SALIENT STATISTICS
U.S. CRUSHED STONE INDUSTRY . . . .
U.S. GYPSUM INDUSTRY
U.S. DIATOMITE INDUSTRY
U.S. PERLITE INDUSTRY
U.S. PUMICE INDUSTRY
U.S. VERMICULITE INDUSTRY
U.S. MICA INDUSTRY
U.S. BARITE INDUSTRY
U.S. FLUORSPAR INDUSTRY
U.S. SALT INDUSTRY
U.S. BORON INDUSTRY
U.S. POTASH INDUSTRY
U.S. SODIUM CARBONATE INDUSTRY . . .
U.S. SODIUM SULFATE INDUSTRY . . . .
7-16
7-21
7-21
7-24
8-9
8-12
8-16
8-18
8-20
8-22
8-24
8-26
8-29
8-31
8-33
8-35
8-37
8-39
8-40
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LIST OF TABLES (continued)
Page
Table 8-16 U.S. CLAY INDUSTRY 8-44
Table 8-17 U.S. FELDSPAR INDUSTRY 8-47
Table 8-18 U.S. KYANITE INDUSTRY 8-48
Table 8-19a U.S. TALC INDUSTRY 8-51
Table 8-19b TECHNICAL PARAMETERS USED IN DEVELOPING CONTROL
SYSTEM COSTS 8-57
Table 8-20 ANNUALIZED COST PARAMETERS 8-60
Table 8-21 FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 9.1 Mg/Hour . . . 8-62
Table 8-22 FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 23 Mg/Hour . . . 8-63
Table 8-23 FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 68 Mg/Hour . . . 8-64
Table 8-24 FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 135 Mg/Hour . . . 8-65
Table 8-25 FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 270 Mg/Hour . . . 8-66
Table 8-26 FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 540 Mg/Hour . . . 8-67
Table 8-27 FABRIC FILTER COSTS FOR NEW MODEL PLANT 2: 9.1 Mg/Hour . . . 8-68
Table 8-28 FABRIC FILTER COSTS FOR NEW MODEL PLANT 2: 23 Mg/Hour . . . 8-69
Table 8-29 FABRIC FILTER COSTS FOR NEW MODEL Plant 2: 68 Mg/Hour . . . 8-70
Table 8-30. FABRIC FILTER COSTS FOR NEW MODEL Plant 2: 135 Mg/Hour . . . 8-71
Table 8-31 FABRIC FILTER COSTS FOR NEW MODEL PLANT 2: 270 Mg/Hour . . . 8-72
Table 8-32 FABRIC FILTER COSTS FOR NEW MODEL PLANT 2: 540 Mg/Hour . . . 8-73
Table 8-33 FABRIC FILTER COSTS FOR PORTABLE MODEL PLANT: 180 Mg/Hour . 8-74
Table 8-34 FABRIC FILTER COSTS FOR EXPANDED MODEL PLANTS 8-80
Table 8-35 FABRIC FILTER COSTS FOR 32 Mg/Hour EXPANDED MODEL PLANT . . 8-81
Table 8-36 MONITORING COSTS FOR NON-METALLIC MINERALS MODEL PLANTS . . 8-90
Table 8-37 RANK ORDER OF INDUSTRIES WITH HIGHEST CONTROL COST IMPACT. . 8-106
Table 8-38 PLANT INVESTMENT COSTS 8-109
xi
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LIST OF TABLES (continued)
Page.
Table 8-39 EXPANSION INVESTMENT COSTS 8-110
Table 8-40 DISCOUNTED CASH FLOW ANALYSES CRUSHED STONE PLANT
136 Mg/hr (150 tph) (IN THOUSANDS OF DOLLARS) 8-113
Table 8-41 SUMMARY OF DCF RESULTS 8-118
Table 8-42 SUMMARY OF DCF RESULTS 8-120
Table 8-43 ESTIMATED NUMBER OF TYPICAL NEW PLANTS REQUIRED TO MEET
PROJECTED PRODUCTION 8-124
Table 8-44 ANNUALIZED CAPITAL AND OPERATING CONTROL COSTS FOR NEW
PLANT CONSTRUCTION 8-125
Table 8-45 ANNUALIZED CONTROL COST PER TON OF INDUSTRY OUTPUT IN
5TH YEAR AND CONTROL COST AS PERCENT OF SELLING PRICE . . . 8-126
XII
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1. SUMMARY
1.1 PROPOSED STANDARDS
Standards of performance to limit emissions of participate matter from
new, modified, and reconstructed non-metallic mineral processing plants are
being proposed under the authority of Section 111 of the Clean Air Act.
Processing of the following minerals is covered by the proposed standards:
Crushed and broken stone
Limestone, Dolomite, Granite, Traprock,
Sandstone, Quartz, Quartzite, Marl,
Marble, Slate, Shell
Sand and gravel
Clay
Kaolinite, Fireclay, Bentonite,
Fuller's Earth, Ball Clay
Rock salt
Gypsum
Sodium compounds
Chloride, Carbonate, Sulfate
Boron
Borax, Kernite, Colemanite
Barite
Fluorspar
Pyri tes
Pyrite, Marcasite, Chalcopyrite
Feldspar
Diatomite
Perlite
Vermiculite
Mica
Kyanite
Andalusite, Sillimanite, Topaz,
Dumortierite
Potash
Sylvite
Pumice
Asphalt and related bitumens
Talc and Pyrophyllite
The proposed standards would limit emissions of particulate matter from the
affected facility defined as the entire processing plant including crushers,
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grinding mills (including air separators, classifiers and conveyors),
screens, bucket elevators, conveyor transfer points, bagging operations,
storage bins and fine product truck and rail car loading stations. Unit
operations not included are drilling, blasting, loading at the mine, hauling,
drying, stockpiling, conveying (other than at transfer points) and windblown
dust from stockpiles, roads and plant yards. The affected facility may be
enclosed by one or more buildings or may be unenclosed.
The proposed standards for particulate matter would limit both fugitive
and stack emissions at the affected facilities. Fugitive emissions, which
are emissions not collected by a capture system, would be limited to visible
emissions for no more than 10 percent of the time over a minimum 1 hour
observation period for all process operations except fine product loading
stations. Fugitive emissions from fine product loading stations would be
limited to visible emissions of no more than 15 percent of the time over a
minimum 1 hour observation period. The proposed standard for stack emissions,
which are emissions collected by a capture system, would limit the concentra-
tion of particulate matter to 0.05 gram per dry standard cubic meter (g/dscm)
(0.02 grain per dry standard cubic foot (gr/dscf)) and 1 percent opacity.
The following small plants would be exempt from the standard: sand and
gravel plants and crushed stone plants with capacities of 22.7 megagrams per
hour (25 tons per hour) or less; and common clay plants and pumice plants with
capacities of 9.1 megagrams per hour (10 tons per hour) or less.
1.2 ENVIRONMENTAL IMPACT
The beneficial and adverse environmental and economic impacts associated
with the proposed standards and with the alternative of setting no standards
are presented in this section. These impacts are discussed in detail in
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Chapter 7, Environmental Effects, and Chapter 8, Economic Impact. A matrix
summarizing these impacts is included in Table 1.1. Appendix B contains a
cross-reference between this document and the Agency's guidelines for
Environmental Impact Statements.
About 550 new non-metallic mineral processing plants will be needed to
process the projected increased production between 1980 and 1985. By 1985,
the proposed standards would reduce the total amount of particulate matter
emissions to the atmosphere by 41,000 megagrams per year (45,000 tons per
year). This reduction is 90 percent greater than that achievable with a
typical state process weight regulation. This will result in a large
positive environmental impact.
The utilization of dry collection techniques (particulate capture com-
bined with a dry emission control device) for control generates no water
effluent discharge. In cases where wet dust suppression techniques could be
used most of the water adheres to the material being processed, resulting in no
significant water discharge. Consequently, emission standards for the non-
metallic minerals industry would have no water pollution impact.
There will be an insignificant negative solid waste disposal impact re-
sulting from the use of dry emission control techniques. Approximately
1.4 megagrams (1.6 tons) of solid waste are collected for every 250 megagrams
(278 tons) of material processed. In many cases, this material may be recycled
back into the process, sold, or used for a variety of purposes. Where no
market exists for the collected fines, they are typically disposed of in the
mine or in an isolated location in the quarry. Where wet dust suppression
can be used, no solid waste disposal problem exists over that resulting from
normal operation.
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TABLE 1.1 MATRIX OF ENVIRONMENTAL AND ECONOMIC IMPACTS OF ALTERNATIVE STANDARDS
Solid Noise
Administrative Air Water waste Energy and Economic Inflation
action impact impact . , impact radiation impact impact
impacL impact
Control based on 000 00 0 0
state standards
NSPS dry collec- +40-1-2 0 -3 0
tions only
KEY: + Beneficial impact 0 No impact
1 Negigible impact
- Adverse impact 2 Small impact
3 Moderate impact
4 Large impact
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The estimated incremental energy requirements of the proposed standards
result from comparing the use of fabric filter baghouses to control
particulate matter emissions to the use of no control system. The estimates
indicate a greater impact than would actually occur because it is expected
that less-energy consuming wet dust suppression systems would be used in
some cases, to achieve the proposed standards. In addition, many new plants
would use baghouses or a combination of baghouses and water sprays to meet
existing State regulations.
The energy required to control all new non-metallic mineral processing
plants constructed by 1985 to the level of the proposed standards would be
about 0.12 million megawatt-hours (0.34 million kilowatt-hours per day).
This would be about a 15 percent increase over the amount of energy which
would otherwise be required to meet projected capacity additons without
controls. This increase would have a minor impact on national energy
demand.
When compared to the noise emanating from crushing and grinding process
equipment, any additional noise from properly designed exhaust fans for the
control system will be insignificant. Consequently, no significant noise
impact is anticipated due to the implementation of standards of performance
for non-metallic minerals plants. There are no known radiation impacts
associated with the proposed standards implementation.
1.3 ECONOMIC IMPACT
The costs and economic impacts associated with the proposed standards
are considered to be reasonable. The estimated impacts are based on a com-
parison of baghouse use to no control. Less expensive wet dust suppression
systems may be used in some cases to achieve the proposed standards. Also,
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many new plants would use baghouses or a combination of baghouses and water
sprays to meet existing State regulations. Thus, the actual economic impact
of the proposed standards would probably be considerably less than the
estimates summarized below.
The costs associated with implementing the proposed standards would not
prevent construction of new non-metallic processing plants which would
be built in the absence of the proposed regulation. However the incremental
costs associated with the best system of emission reduction may preclude
the construction of new pumice plants and common clay plants with capacities
of 9.1 Mg/hr (10 ton/hr) or less, and sand and gravel plants and crushed
stone plants with capacities of 22.7 Mg/hr (25 ton/hr) or less. For this
reason these plants would be exempt from the proposed regulation.
1.4 INFLATION IMPACT
The costs associated with the proposed standards for new and modified
facilities at non-metallic mineral processing plants have been judged not to
be of such magnitude to require an analysis of the inflationary impact. These
criteria have been outlined in an Agency publication and include:
1. National annualized cost of compliance.
2. Total added production cost in relation to sales price.
3. Net national energy consumption increase.
4. Added demands or decreased supplied of selected materials.
Should any of the guideline values listed under these criteria be exceeded,
a full inflationary impact assessment is required.
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2. INTRODUCTION
Standards of performance are proposed following a detailed investigation
of air pollution control methods available to the affected industry and the
impact of their costs on the industry. This document summarizes the informa-
tion obtained from such a study. Its purpose is to explain in detail the
background and ba'sis of the proposed standards and to facilitate analysis of
the proposed standards by interested persons, including those who may not be
familiar with the many technical aspects of the industry. To obtain addition-
al copies of this document or the Federal Register notice of proposed standards,
write to EPA Library (MD-35), Research Triangle Park, North Carolina 27711.
Specify "Non-Metallic Mineral Processing Plants, Background Information:
Proposed Standards," Document number EPA-450/2-79- when ordering.
2.1 AUTHORITY FOR THE STANDARDS
Standards of performance for new stationary sources are established under
section 111 of the Clean Air Act (42 U.S.C. 7411), as amended, hereafter
referred to as the Act. Section 111 directs the Administrator to establish
standards of performance for any category of new stationary source of air
pollution which ". . . causes or contributes significantly to, air pollution
which may reasonably be anticipated to endanger public health or welfare."
The Act requires that standards of performance for stationary sources
reflect, ". . . the degree of emission limitation achievable through the
application of the best technological system of continuous emission reduction
. . . the Administrator determines has been adequately demonstrated." In
addition, for stationary sources whose emission result from fossil fuel
combustion, the standard must also include a percentage reduction in emissions.
The Act also provides that the cost of achieving the necessary emission
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reduction, the nonair quality health and environmental impacts and the energy
requirements all be taken into acccount in establishing standards of perfor-
mance. The standards apply only to stationary sources, the construction or
modification of which commences after regulations are proposed by publication
in the Federal Register.
The 1977 amendments to the Act altered or added numerous provisions
which apply to the process of establishing standards of performance.
1. EPA is required to list the categories of major stationary sources
which have not already been listed and regulated under standards of perfor-
mance. Regulations must be promulgated for these new categories on the
following schedule:
25 percent of the listed categories by August 7, 1980.
75 percent of the listed categories by August 7, 1981.
100 percent of the listed categories by August 7, 1982.
A governor of a State may apply to the Administrator to add a category
which is not on the list or to revise a standard of performance.
2. EPA is required to review the standards of performance every four
years, and if appropriate, revise them.
3. EPA is authorized to promulgate a design, equipment, work practice,
or operational standards when an emission standard is not feasible.
4. The term "standards of performance" is redefined and a new term
"Technological system of continuous emission reduction" is defined. The
new definitions clarify that the control system must be continuous and may
include a low-polluting or non-polluting process or operation.
5. The time between the proposal and promulgation of a standard under
Section 111 of the Act is extended to six months.
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Standards of performance, by themselves, do not guarantee protection
of health or welfare because they are not designed to achieve any specific
air quality levels. Rather, they are designed to reflect the degree of
emission limitation achievable through application of the best adequately
demonstrated technological system of continuous emission reduction,
taking into consideration the cost of achieving such emission reduction,
any nonair quality health and environmental impact and energy requirements.
Congress had several reasons for including these requirements.
First, standards with a degree of uniformity are needed to avoid situations
where some States may attract industries by relaxing standards relative
to other States. Second, stringent standards enhance the potential for
long term growth. Third, stringent standards may help achieve long-term
cost savings by avoiding the need for more expensive retrofitting when
pollution ceilings may be reduced in the future. Fourth, certain types
of standards for coal burning sources can adversely affect the coal
market by driving up the price of low-sulfur coal or effectively
excluding certain coals from the reserve base because their untreated
pollution potentials are high. Congress does not intend that new source
performance standards contribute to these problems. Fifth, the standard-
setting process should create incentives for improved technology.
Promulgation of standards of performance does not prevent State or
local agencies from adopting more stringent emission limitations for the
same sources. States are free under section 116 of the Act to establish
even more stringent emission limits than those established under section
111 or those necessary to attain or maintain the national ambient air
quality standards (NAAQS) under section 110. Thus, new sources may in
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some cases be subject to limitations more stringent than standards of
performance under section 111, and prospective owners and operators of
new sources should be aware of this possibility in planning for such
facilities.
A similar situation may arise when a major emitting facility is to
be constructed in a geographic area which falls under the prevention of
significant deterioration of air quality provisions of Part C of the
Act. These provisions require, among other things, that major emitting
facilities to be constructed in such areas are to be subject to best
available control technology. The term "best available control tech-
nology" (BACT), as defined in the Act, means ". . .an emission limitation
based on the maximum degree of reduction of each pollutant subject to
regulation under this Act emitted from or which results from any major
emitting facility, which the permitting authority, on a case-by-case
basis, taking into account energy, environmental, and economic impacts
and other costs, determines is achievable for such facility through
application of production processes and available methods, systems, and
techniques, including fuel cleaning or treatment or innovative fuel
combustion techniques for control of each such pollutant. In no event
shall application of 'best available control technology' result in
emissions of any pollutants which will exceed the emissions allowed by
any applicable standard established pursuant to section 111 or 112 of
this Act."
Although standards of performance are normally structured in terms
of numerical emission limits where feasible, alternative approaches are
sometimes necessary. In some cases physical measurement of emissions
2-4
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from a new source may be impractical or exorbitantly expensive. Section
lll(h) provides that the Administrator may promulgate a design or
equipment standard in those cases where it is not feasible to prescribe
or enforce a standard of performance. For example, emissions of
hydrocarbons from storage vessels for petroleum liquids are greatest
during tank filling. The nature of the emissions, high concentrations
for short periods during filling, and low concentrations for longer
periods during storage, and the configuration of storage tanks make
direct emission measurement impractical. Therefore, a more practical
approach to standards of performance for storage vessels has been
equipment specification.
In addition, section lll(j) authorizes the Administrator to grant
waivers of compliance to permit a source to use innovative continuous
emission control technology. In order to grant the waiver, the Administrator
must find: (1) a substantial likelihood that the technology will produce
greater emission reductions than the standards require, or an equivalent
reduction at lower economic energy or environmental cost; (2) the proposed
system has not been adequately demonstrated; (3) the technology will not
cause or contribute to an unreasonable risk to the public health,
welfare or safety; (4) the governor of the State where the source is
located consents; and that, (5) the waiver will not prevent the
atttainment or maintenance of any ambient standard. A waiver may have condition:
attached to assure the source will not prevent attainment of any NAAQS.
Any such condition will have the force of a performance standard.
Finally, waivers have definite end dates and may be terminated earlier
if the conditions are not met or if the system fails to perform as
2-5
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expected. In such a case, the source may be given up to three years to
meet the standards, with a mandatory progress schedule.
2.2 SELECTION OF CATEGORIES OF STATIONARY SOURCES
Section 111 of the Act directs the Adminstrator to list categories
of stationary sources which have not been listed before. The Adminstrator,
"... shall include a category of sources in such list if in his judgement
it causes, or contributes significantly to, air pollution which may
reasonably be anticipated to endanger public health or welfare."
Proposal and promulgation of standards of performance are to follow
while adhering to the schedule referred to earlier.
Since passage of the Clean Air Amendments of 1970, considerable
attention has been given to the development of a system for assigning
priorities to various source categories. The approach specifies areas
of interest by considering the broad strategy of the Agency for implementing
the Clean Air Act. Often, these "areas" are actually pollutants which
are emitted by stationary sources. Source categories which emit these
pollutants were then evaluated and ranked by a process involving such
factors as (1) the level of emission control (if any) already required
by State regulations; (2) estimated levels of control that might be
required from standards of performance for the source category;
(3) projections of growth and replacement of existing facilities for the
source category; and (4) the estimated incremental amount of air pollution
that could be prevented, in a preselected future year, by standards of
performance for the source category. Sources for which new source
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performance standards were promulgated or are under development during
1977 or earlier, were selected on these criteria.
The Act amendments of August, 1977, establish specific criteria to
be used in determining priorties for all source categories not yet
listed by EPA. These are
1) the quantity of air pollutant emissions which each such category
will emit, or will be designed to .emit;
2) the extent to which each such pollutant may reasonably be
anticipated to endanger public health or welfare; and
3) the mobility and competitive nature of each such category of
sources and the consequent need for nationally applicable new source
standards of performance.
In some cases, it may not be feasible to immediately develop a
standard for a source category with a high priority. This might happen
when a program of research is needed to develop control techniques or
because techniques for sampling and measuring emissions may require
refinement. In the developing of standards, differences in the time
required to complete the necessary investigation for different source
categories must also be considered. For example, substantially more
time may be necessary if numerous pollutants must be investigated from a
single source category. Further, even late in the development process
the schedule for completion of a standard may change. For example,
inablility to obtain emission data from well-controlled sources in time
to pursue the development process in a systematic fashion may force a
change in scheduling. Nevertheless, priority ranking is, and will
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continue to be, used to establish the order in which projects are
initiated and resources assigned.
After the source category has been chosen, determining the types of
facilities within the source category to which the standard will apply
must be decided. A source category may have several facilities that
cause air pollution and emissions from some of these facilities may be
insignificant or very expensive to control. Economic studies of the
source category and of applicable control technology may show that air
pollution control is better served by applying standards to the more
severe pollution sources. For this reason, and because there be no
adequately demonstrated system for controlling emissions from certain
facilities, standards often do not apply to all facilities at a source.
For the same reasons, the standards may not apply to all air pollutants
emitted. Thus, although a source category may be selected to be covered
by a standard of performance, not all pollutants or facilities within
that source category may be covered by the standards.
2.3 PROCEDURE FOR DEVELOPMENT OF STANDARDS OF PERFORMANCE
Standards of performance must (1) realistically reflect best demon-
strated control practice; (2) adequately consider the cost, and the
nonair quality health and environmental impacts and energy requirements
of such control; (3) be applicable to existing sources that are
modified or reconstructed as well as new installations; and (4) meet
these conditions for all variations of operating conditions being
considered anywhere in the country.
The objective of a program for development of standards is to
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identify the best technological system of continuous emission reduction
which has been adequately demonstrated. The legislative history of
section 111 and various court decisions make clear that the Administrator's
judgement of what is adequately demonstrated is not limited to systems
that are in actual routine use. The search may include a technical
assessment of control systems which have been adequately demonstrated
but for which there is limited operational experience. In most cases,
determination of the "... degree of emission reduction achievable ..."
is based on results of tests of emissions from well controlled existing
sources. At times, this has required the investigation and measurement
of emissions from control systems found in other industrialized countries
that have developed more effective systems of control than those available
in the United States.
Since the best demonstrated systems of emission reduction may not
be widespread use, the data base upon which standards are developed may
be somewhat limited. Test data on existing well-controlled sources are
obvious starting points in developing emission limits for new sources.
However, since the control of existing sources generally represent
retrofit technology or was originally designed to meet an existing State
or local regulation, new sources may be able to meet more stringent
emission standards. Accordingly, other information must be considered
before a judgement can be made as to the level at which the emission
standard should be set.
A process for the development of a standard has evolved which takes
into account the following considerations.
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1. Emissions from existing well-controlled sources as measured.
2. Data on emissions from such sources are assessed with considera-
tion of such factors as: (a) how representative the tested source is in
regard to feedstock, operation, size, age, etc.; (b) age and maintenance
of control equipment tested; (c) design uncertainties of control
equipment being considered; and (d) the degree of uncertainty that new
sources will be able to achieve similar levels of control.
3. Information from pilot and prototype installations, guarantees
by vendors of control equipment, unconstructed but contracted projects,
foreign technology, and published literature are also considered during
the standard development process. This is especially important for
sources where "emerging" technology appears to be a significant alternative
4. Where possible, standards are developed which permit the use of
more than one control technique or licensed process.
5. Where possible, standards are developed to encourage or permit
the use of process modifications or new processes as a method of control
rather than "add-on" systems of air pollution control.
6. In appropriate cases, standards are developed to permit the use
of systems capable of controlling more than one pollutant. As an example,
a scrubber can remove both gaseous and particulate emissions, but an
electrostatic precipitator is specific to particulate matter.
7. Where appropriate, standards for visible emissions are developed
in conjunction with concentration/mass emission standards. The opacity
standard is established at a level that will require proper operation
and maintenance of the emission control system installed to meet the
concentration/mass standard on a day-to-day basis. In some cases,
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however, it is not possible to develop concentration/mass standards,
such as with fugitive sources of emissions. In these cases, only
opacity standards may be developed to limit emissions.
2.4 CONSIDERATION OF COSTS
Section 317 of the Act requires, among other things, an economic
impact assessment with respect to any standard of performance established
under section 111 of the Act. The assessment is required to contain an
analysis of:
(1) the costs of compliance with the regulation and standard
including the extent to which the cost of compliance varies depending on
the effective date of the standard or regulation and the development of
less expensive or more efficient methods of compliance;
(2) the potential inflationary recessionary effects of the standard
or regulation;
(3) the effects on competition of the standard or regulation with
respect to small business;
(4) the effects of the standard or regulation on consumer cost;
and,
(5) the effects of the standard or regulation on energy use.
Section 317 requires that the economic impact assessment be as
extensive as practible, taking into account the time and resources
available to EPA.
The economic impact of a proposed standard upon an industry is
usually addressed both in absolute terms and by comparison with the
control costs that would be incurred as a result of compliance with
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typical existing State control regulations. An incremental approach is
taken since both new and existing plants would be required to comply with
State regulations in the absence of a Federal standard of performance.
This approach requires a detailed analysis of the impact upon the
industry resulting from the cost differential that exists between a
standard of performance and the typical State standard.
The costs for control of air pollutants are not the only costs
considered. Total environmental costs for control of water pollutants
as well as air pollutants are analyzed wherever possible.
A thorough study of the profitability and price-setting mechanisms
of the industry is essential to the analysis so that an accurate estimate
of potential adverse economic impacts can be made. It is also essential
to know the capital requirements placed on plants in the absense of
Federal standards of performance so that the additional capital requirements
necessitated by these standards can be placed in the proper perspective.
Finally, it is necessary to recognize any constraints on capital availability
within an industry, as this factor also influences the ability of new
plants to generate the capital required for installation of additional
control equipment needed to meet the standards of performance.
2.5 CONSIDERATION OF ENVIRONMENTAL IMPACTS
Section 102(2)(C) of the National Environmental Policy Act (NEPA)
of 1969 requires Federal agencies to prepare detailed environmental
impact statements on proposals for legislation and other major Federal
actions significantly affecting the quality of the human environment.
The objective of NEPA is to build into the decision-making process of
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Federal agencies a careful consideration of all environmental aspects of
proposed actions.
In a number of legal challenges to standards of performances for
various industries, the Federal Courts of Appeals have held that
environmental impact statements need not be prepared by the Agency for
proposed actions under section 111 of the Clean Air Act. Essentially,
the Federal Courts of Appeals have determined that "... the best
system of emission reduction, . . . require(s) the Administrator to take
into account counter-productive environmental effects of a proposed
standard, as well as economic costs to the industry. . ." On this
basis, therefore, the Courts "... established a narrow exemption from
NEPA for EPA determination under section 111."
In addition to these judicial determinations, the Energy Supply and
Environmental Coordination Act (ESECA) of 1974 (PL-93-319) specifically
exempted proposed actions under the Clean Air Act from NEPA requirements.
According to section 7(c)(l), "No action taken under the Clean Air Act
shall be deemed a major Federal action significantly affecting the
quality of the human environment within the meaning of the National
Environmental Policy Act of 1969."
The Agency has concluded, however, that the preparation of environmental
impact statements could have beneficial effects on certain regulatory
actions. Consequently, while not legally required to do so by section
102(2)(C) of NEPA, environmental impact statements are prepared for
various regulatory actions, inlcuding standards of performance developed
under section 111 of the Act. This voluntary preparation of environmental
impact statements, however, in no way legally subjects the Agency to
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NEPA requirements.
To implement this policy, a separate section is included in this
document which is devoted solely to an analysis of the potential environmental
impacts associated with the proposed standards. Both adverse and bene-
ficial impacts in such areas as air and water pollution, increased solid
waste disposal, and increased energy consumption are identified and
discussed.
2.6 IMPACT ON EXISTING SOURCES
Section 111 of the Act defines a new sources as ". . . any stationary
source, the construction or modification of which is commenced ..."
after the proposed standards are published. An existing source becomes
a new source if the source is modified or is reconstructed. Both modification
and reconstruction are defined in amendments to the general provisions
of Subpart A of 40 CRF Part 60 which were promulgated in the Federal
Register on December 16, 1975 (40 FR 58416). Any physical or operational
change to an existing facility which results in an increase in the
emission rate of any pollutant for which a standard applies is considered
a modification. Reconstruction, on the other hand, means the replacement
of components of an existing facility to the extent that the fixed
capital cost exceeds 50 percent of the cost of constructing a comparable
entirely new source and that it be technically and economically feasible
to meet the applicable standards. In such cases, reconstruction is
equivalent to a new construction.
Promulgation of a standard of performance requires States to establish
standards of performance for existing sources in the same industry under
section lll(d) of the Act if the standard for new sources limits emissions
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of a designated pollutant (i.e., a pollutant for which air quality criteria
have not been issued under section 108 or which has not been listed as a
hazardous pollutant under section 112). If a State does not act, EPA must
establish such standards. General provisions outlining procedures for
control of existing sources under section lll(d) were promulgated on
November 17, 1975, as Subpart B of 40 CFR Part 60 (40 FR 53340).
2.7 REVISION OF STANDARDS OF PERFORMANCE
Congress was aware that the level of air pollution control achievable
by any industry may improve with technological advances. Accordingly,
section 111 of the Act provides that the Administrator "... shall, at
least every four years, review and, if appropriate, revise ..." the
standards. Revisions are made to assure that the standards continue to
reflect the best systems that become available in the future. Such
revisions will not be retroactive but will apply to stationary sources
constructed or modified after the proposal of the revised standards.
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3. THE NON-METALLIC MINERALS INDUSTRY
3.1 GENERAL
There are many non-metallic minerals which are individually produced
in a wide range of quantities. For example, the annual domestic demand for
sand, gravel and stone is quoted in millions of tons, whereas the production
of industrial diamonds and gem stones is measured in carats. Previous EPA
studies have investigated some of these non-metallic minerals, namely, coal,
phosphate rock and asbestos. The 20 non-metallic minerals selected for in-
vestigation in this study are:
Crushed and Broken Stone Boron
Sand and Gravel Barite
Clay Fluorspar
Rock Salt Pyrites
Gypsum Feldspar
Sodium compounds Diatomite
Potash Perlite
Pumice Vermiculite
Natural Asphalt and Related Bitumens Mica
Talc Kyanite
These 20 categories are based upon Bureau of Mines classifications and are
the highest mined production segments of the non-metallic minerals industry
which have crushing and grinding operations, excluding coal, phosphate
rock, and asbestos.
Total domestic production of these non-metallic minerals for 1975 was
about 1607 million megagrams (1772 million short tons). The estimated domes-
tic production level of these minerals in 1980 has been projected to be 1833
million megagrams (2020 million short tons). Value of the minerals ranges
3-1
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from 1.1 dollars/megagram (1.0 dollars/ton) for low grade clay, to 276 dollars/
megagram (250 dollars/ton) for high grade talc. Geographically, the non-metallic
minerals industry is highly dispersed, with all States reporting production of
at least one of these 20 non-metallic minerals. The industry is also extremely
diverse in terms of production capacities per facility (from 5 to several thousand
tons per hour) and end product uses.
3.1.1 Industry Characteristics
Table 3.1 presents industry characteristics for each mineral under con-
sideration. Crushed stone and sand and gravel are by far the largest segments
accounting for 1523 million megagrams (1680 million tons) of the 1607 million
megagrams (1771 million tons) produced by the 20 industries. There are about
5500 processing plants in the sand and gravel industry and about 4800 quarries
worked in the crushed stone industry. Each of the other industries has less
than 100 processing plants, except for the clay industry which has about 120
plants.
Sand and gravel plants are located in every state. Crushed stone plants
are located in every state except Delaware. Clay plants are located in every
state except Vermont, Rhode Island, and Alaska. Processing plants for the
other industries are usually distributed among a few states where those
minerals deposits are located. Two of the minerals are principally mined and
processed in only one state: boron only in California, and potash primarily
in New Mexico.
Projected growth rates are also presented in Table 3.1. The growth rates
are projected to increase at compounded annual rates of up to 6 percent
through the year 1985.
3-2
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TABLE 3.1 INDUSTRY CHARACTERISTICS1'3
Mineral
Crushed and
broken stone
Sand and gravel
Clay
Rock Salt
Gypsum (crude)
Sodium*
compounds
Potash}
Pumice
Natural asphalt and
Bitumens
Talc
Boron
Barlte
Fluorspar
Pyrites
1975
Production
1000 megagrams (1000 tons)
807,000 (890,000)
716,015 (789,432)
44,485 (49,047)
14,928 (13,540)
8,844 (9,751)
4,529 (4,895)
2,268 (2,501)
3,530 (3.892)
related 90 (100)
875 (965)
1,063 (1 ,172)
1,167 (1,287)
126 (140)
367 (450) 5
1975
Price
(Dollars/Mg)
2.63
1.97
1.10-221.00
29.78
5.05
46.54-45.75+
73.00
3.17
-
5.50-276.00
110
17.71
88-106
13.00*
arowthUrate Major Produc1n9 states
(S) 1n order of Product1on
4.0 Pennsylvania
Illinois
Texas
Florida
Ohio
1.0 Alaska
California
Michigan
Illinois
Texas
Ohio
3.3 Georgia
Texas
Ohio
North Carolina
2.0 Texas
New York
Louisiana
2.0 California
Michigan
Iowa
Texas
2.5 California
Texas
3.0 New Mexico
3.5 Oregon
California
Arizona
New Mexico
2.0 Utah
4.0 Vermont
Texas
California
5.0 California
2.2 Nevada
Missouri
3.0 Illinois
Tennessee
Number of active
operations
4800 (quarries)
5500 (plants)
120
21
69 (mines)
37
11
235
1
52
6
31
15
3
(continued)
3-3
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TABLE 3.1 (continued)
Mineral
Feldspar
Diatomite
Perl i te
Vernriculite
Mica
Kyani te
1975
Production
1000 megagrams (1000 tons)
607
519
640
299
122
85
(670)
(573)
(706)
(330)
(135)
(94)**
1975
Price
(Dollars/Kg)
19.30
88.25
15.72
46.06
42.64
Annual
growth rate
(X)
4.0
5.5
4.0
4.0
4.0
6.0
Major producing states
in order of production
North Carolina
California
Kansas
Nevada
New Mexico
Montana
South Carolina
North Carolina
New Mexico
Virginia
Georgia
Number of active
operations
15
16
13
2
17
3
Natural soda ash.
Sodium sulfate price.
iK2 equivalent.
Based on sulfur production by assuming a 40 percent content.
Price of fugitive ores.
Estimates for 1974.
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3.1.2 End Uses
End uses for the non-metallic minerals are many and diverse. The min-
erals may be used either directly in their natural state or processed into
a variety of manufactured products. Generally, they can be classified as
either minerals for the construction industry; minerals for the chemical and
fertilizer industries; or clay, ceramic, refractory and miscellaneous min-
erals. Minerals generally used for construction are crushed and broken stone,
sand and gravel, gypsum, asphalt and related bitumens, perlite, pumice,
vermiculite, and mica. Minerals generally used in the chemical and fertilizer
industries are barite, fluorspar, potash, boron, rock salt, and sodium com-
pounds. Clay, feldspar, kyanite, talc and diatomite can be generally clas-
sified as clay, ceramic, refractory, and miscellaneous minerals. Table 3.2
lists the major uses of each individual mineral.
3.1.3 Rock Types and Distribution
Major rock types processed by the crushed and broken stone industry in-
clude limestone and dolomite (which accounted for 73.2 percent of the total
tonnage in 1973 and has the widest and most important end use range); granite
(11.4 percent), trap rock (7.9 percent) and sandstone, quartz and quartzite
(2.9 percent). Rock types including calcereous marl, marble, shell, slate
and miscellaneous others accounted for only 4.6 percent. Classifications used
by the industry vary considerably and in many cases do not reflect actual
geological definitions.
Limestone and dolomite are sedimentary rocks formed from accumulations of
animal remains or chemical precipitation of carbonates in water. In a pure
state, limestone consists of crystalline or granular calcium carbonate
(calcite), while dolomite consists of calcium-magnesium carbonate (dolomite).
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TABLE 3.2 MAJOR USES OF THE NON-METALLIC MINERALS
Mineral
Major uses
Crushed and broken stone
Sand and gravel
Clay
Rock salt
Gypsum
Sodium compounds
Potash
Pumice
Natural asphalt and related
bitumens
Talc
Boron
Barite
Fluorspar
Feldspar
Pyrites
Di atomi te
Perlite
Vermiculite
Mica
Kyanite
Construction, lime manufacturing
Construction
Bricks, cement, refractory, paper
Highway use, chlorine
Wall board, plaster, cement, agriculture
Glass, chemicals, paper
Agriculture, chemicals
Road construction, concrete
Asphalt paving
Ceramics, paint, toilet preparations
Glass, soaps, fertilizer
Drilling mud, chemicals
Hydrofluoric acid, iron and steel, glass
Glass, ceramics
Sulfuric acid
Filtration, filters
Insulation, filter aid, plaster aggregate
Concrete
Paint, joint cement, roofing
Refractories, ceramics
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Both are often found together in the same rock deposit. Depending on the pro-
portions of each, the rock may be classified as limestone, dolomitic limestone,
calcareous dolomite or dolomite. Deposits are common and are distributed
throughout most parts of the country, although primarily located in the Central,
Middle Atlantic and South Atlantic regions which combined accounted for over
93 percent of the total production in 1973.
Commercially, granite consists of any light-colored, coarse-grained
igneous rock. It is composed chiefly of quartz, feldspar and, usually mica.
Deposits are located in the South Atlantic, northeastern, North Central and
western regions of the country. The South Atlantic region accounted for more
than 77 percent of the total tonnage of granite produced in 1973.
Trap rock includes any dark colored, fine-grained igneous rock composed
of the ferro-magnesian minerals and basic feldspars with little or no quartz.
Common varieties include basalts, diabases and gabbros. Deposits are mostly
found in the New England, Middle Atlantic and Pacific regions, which combined
accounted for 76 percent of all trap rock produced in 1973.
Sandstones and quartzitic rocks are scattered throughout the country.
Sandstones are sedimentary rocks composed predominantly of cemented quartz
grains. The cementing material may be calcium carbonate, iron oxide or clay.
Quartzites are metamorphosed siliceous sandstones. All regions accounted for
some production of sandstone and quartz, with the Pacific and West South
Central and Middle Atlantic States combining for 60 percent of the total.
Sand and gravel are products of the weathering of rocks and thus consist
predominantly of silica. Often, varying amounts of other minerals such as iron
oxides, mica, and feldspar are present. Deposits are common and are distributed
throughout the country.
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Clays are a group of fine-grained non-metallic minerals which are mostly
hydrous aluminum silicates that contain various amounts of organic and inorganic
impurities. Clays are classified into six groups by the Bureau of Mines:
kaolin, ball clay, fire clay, bentonite, fuller's earth, and miscellaneous
(common) clay.
Kaolin is a clay in which the predominant clay mineral is kaolinite. Large
quantities of high quality kaolin are found in Georgia. Ball clay consists
principally of kaolinite, but has a higher silica-to-alumina ratio than is found
in most kaolin, as well as larger quantities of mineral impurities and much
organic material. Ball clays are mined in Kentucky, Tennessee, and New Jersey.
The terms "fire clay" and "stoneware clay" are based on refractoriness or
on intended usage (fire clay indicating potential use for refractories, and
stoneware clay indicating uses for such items as crocks, jugs, and jars). Fire
clays are basically kaolinitic but include other clay minerals and impurities.
Included under the general term fire clay are the diaspore, burley, and burley-
flint clays. Fire clay deposits are widespread in the United States, with the
greatest reserves being found in the Middle Atlantic regions.
Bentonites are composed essentially of minerals of the montmorillonite
group. The swelling type has a high sodium iron concentration, whereas the
nonswelling types are usually high in calcium. Bentonite is presently produced
in Wyoming and Montana.
Fuller's earths are essentially montmorillonite or attapulgite. A small
area in Georgia and Florida contains the known reserve of attapulgite-type
fuller's earth.
The term "miscellaneous (common) clay" is a statistical designation used
by the Bureau of Mines to refer to clays and shales not included under the other
3-8
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five clay types. Miscellaneous clay may contain some kaolinite and mont-
morillonite, but illite usually predominates, particularly in the shales.
Miscellaneous clay is widespread throughout the United States.
Rock salt consists of sodium chloride and is the chief source of_all
forms of sodium. Rock salt is mined on a large scale in Michigan, Texas,
New York, Louisiana, Ohio, Utah, New Mexico, and Kansas.
Gypsum is a hydrous calcium sulfate normally formed as a chemical pre-
cipitate from marine waters of high salinity. Domestic reserves of gypsum
are geographically distributed in 23 states. Areas deficient in gypsum
reserves are Minnesota, Wisconsin, the Pacific Northwest, the New England States,
the deep South to the east of Louisiana, and northern California.
Sodium is a chemically reactive metallic element used chiefly in the form
of its many compounds. Although too reactive to be found in the uncombined form
in nature, the compounds of sodium are plentiful. Sodium chloride (salt) is
the chief source of all forms of sodium. Increasing quantities of sodium car-
bonate (soda ash) and sodium sulfate (salt cake) are produced from natural de-
posits of these compounds, but salt is still the main source of both. Natural
sodium carbonate occurs in Wyoming and saline lake brines in California.
Natural sodium sulfate is produced from deposits in California, Texas, and
Wyomi ng.
Potash denotes materials with a chemical combination of the element
potassium with one or more elements. Sylvinite, the major ore for producing
potash, comes from underground mines in New Mexico, and is a mineralogical
mixture of sylvite (KC1) and halite (NaCl).
Pumice is a rock of igneous origin, ranging from acidic to basic in com-
position, with a cellular structure formed by explosive or effusive volcanism.
3-9
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The commercial designation includes the more precise petrographic descriptions
for pumice, pumicite (volcanic ash), volcanic cinders, and scoria. Deposits
are mostly found in the Western States.
Natural asphalt and related bitumens are defined as mixtures of hydro-
carbons of natural or pyrogenous origin or combinations of both, frequently
accompanied by their derivatives, which may be gaseous, liquid, semisolid or
solid, and which are completely soluble in carbon disulfide. The principal
bituminous materials of commercial interest are: natural asphalt, native
asphaltites (such as gilsonite, grahamite, and glance pitch), asphaltic
pyrobitumens (wurtzilite and eloterite) and mineral waxes (such as ozokerite).
Commercial deposits of bituminous limestone or sandstone in the United States
are found in Texas, Oklahoma, Louisiana, Utah, Arkansas, California, and
Alabama. Gilsonite is found in the Uintah basin in Utah and Colorado.
Wurtzilite is found in Uintah County, Utah.
The mineral talc is a soft hydrous magnesium silicate, 3 MgO-4Si02
H20. The talc of highest purity is derived from magnesium-rich metamorphic
carbonate rocks; less pure talc from metamorphosed ultra basic igneous rocks.
Soapstone is a term used for a massive form of rock containing the mineral.
Pyrophyllite (Al203-4Si02-H20) is a hydrous aluminum silicate similar to talc
in properties. It is principally found in North Carolina. Talc-group min-
erals are principally produced in New York, Texas, Vermont, California, and
Montana.
Boron is a versatile and useful element used mainly in the form of its
many compounds, of which borax and boric acid are the best known. Many min-
erals contain boron, but only a few are commercially valuable as sources of
boron. The principal boron minerals are borax, kernite, and colemanite.
3-10
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Half of the commercial world reserves are in southern California as bedded
deposits of borax (sodium borate) and colemanite (calcium borate), or as solu-
tions of boron minerals in Searles Lake brines.
Barite is almost pure barium sulfate (BaSOiJ and is the principal com-
mercial mineral source of barium and barium compounds. The reserves are
principally in Missouri and the southern Appalachian States, the remainder
is in Arkansas, Nevada, and California.
Fluorine is derived from the mineral fluorite (CaF2), commonly known as
fluorspar. Fluorspar is principally found in deposits located in Kentucky
and Illinois.
Pyrites are iron sulfide minerals that are roasted to yield sulfur di-
oxide. They include pyrite (FeS2)» marcasite (FeS2), and chalcopyrite
(CuFeS2). Large pyrite deposits occur along the Appalachian belt.
Feldspar is a general term used to designate a group of closely related
minerals, especially abundant in igneous rocks and consisting essentially of
aluminum silicates in combination with varying proportions of potassium, sodium,
and calcium. The principal feldspar species are orthclase or microcline
(both K20-Al203-6Si02), albite (Na20-Al203-6Si02) and anorthite (CaO-Al203-
2Si02). North Carolina is the foremost domestic producer, followed in order
of output by California, Connecticut, and Georgia.
Diatomite is a material of sedimentary origin consisting mainly of an
accumulation of skeletons or frustules formed as a protective covering by
diatoms, single-celled microscopic plants. The skeletons are essentially
amorphous hydrated or opaline silica but occasionally are partly composed of
alumina. The terms "diatomaceous earth" and "kieselguhr" are sometimes used
interchangeably and are synonymous with diatomite. Diatomite is found only in
3-11
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the Western States with a substantial part of the total reserve found in the
Lompoc, California area.
Perlite is chemically a metastable amorphus aluminum silicate with minor
impurities and inclusions of various other metal oxides and minerals. Perlite
is mostly found in the Western States.
Vermiculite is a micaceous mineral with a ferromagnesiurn-aluminum silicate
composition and the property of exfoliating to a low-density material when
heated. Presently, vermiculite is mined from deposits located in Montana and
South Carolina.
Mica is a group name for a number of complex hydrous potassium aluminum
silicate minerals differing in chemical composition and physical properties but
characterized by excellent basal cleavage that facilitates splitting into thin,
tough, flexible, elastic sheets. These minerals can be classified into four
principal types named after the most common mineral in each group - muscovite
(potassium mica), phlogopite (magnesium mica), biotite (iron mica), and lepi-
dolite (lithium mica). The major producing regions in the United States are
the Southeast and West.
Kyanite and the related minerals - andalusite, sillimanite, dumortierite,
and topaz - are natural aluminum silicates which can be converted to mullite,
a stable refractory raw material. Reserves of kyanite and the related min-
erals are mostly found in Virginia, North and South Carolina, Idaho, and
Georgia.
3.2 NON-METALLIC MINERALS PREPARATION PROCESSES AND THEIR EMISSIONS
3.2.1 General Process Description
Non-metallic mineral processing involves extracting from the ground;
loading, unloading, and dumping, conveying, crushing, screening, milling, and
3-12
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classifying. Some minerals processing also includes washing, drying, calcin-
ing, or flotation operations. The operations performed depend on the rock
type and the desired product.
The mining techniques used for the extraction of non-metallic minerals
vary with the particular mineral, the nature of the deposit, and the location
of the deposit. Mining is carried out both underground and in open pits.
Some minerals require blasting while others can be removed by bulldozer or
dredging operations alone.
The non-metallic minerals are normally delivered to the processing plant
by truck, and dumped into a hoppered feeder, usually a vibrating grizzly type,
or on to screens, as illustrated in Figure 3.1. These screens separate or
scalp the larger boulders from the finer rocks that do not require primary
crushing, thus minimizing the load to the primary crusher. Jaw or gyratory
crushers are usually used for initial reduction, although impact crushers are
gaining favor for crushing low-abrasion rock, such as limestones, and talc, and
where high reduction ratios are desired. The crusher product, normally 7.5
to 30 centimeters (3 to 12 inches) in size, and the grizzly throughs (undersize
material) are discharged onto a belt conveyor and normally transported to either
secondary screens and crusher, or to a surge pile or silo for temporary storage.
The secondary screens generally separate the process flow into either two or
three fractions (oversize, undersize, and throughs) prior to the secondary crusher.
The oversize is discharged to the secondary crusher for further reduction. The
undersize, which require no further reduction at this stage, normally by-pass the
secondary crusher. A third fraction, the throughs, is separated when processing
some minerals. Throughs contain unwanted fines that are usually removed from the
process flow and stockpiled as crusher-run material. For secondary crushing,
3-13
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SURGE PILE
CO
i
FINISHING
SCREENS
Figure 3.1 Flowsheet of a Typical Crushing Plant
-------
gyratory or cone crushers are most commonly used, although impact crushers are used
at some installations.
The product from the secondary crushing stage, usually 2.5 centimeters (one
inch) or less in size, is normally transported to a secondary screen for further
sizing. Sized material from this screen is either discharged directly to a
tertiary crushing stage or conveyed to a fine-ore bin which supplies the milling
stage. Cone crushers or hammermills are normally used for tertiary crushing. Rod
mills, ball mills, and hammermills, are normally used in the milling stage. The
product from the tertiary crusher or the mill is usually conveyed to a type of
classifier such as a dry vibrating screen system, an air separator, or a wet rake
or spiral system (if wet grinding was employed) which also dewaters the material.
The oversize is returned to the tertiary crusher or mill for further size
reduction. At this point, some mineral end products of the desired grade are
conveyed directly to finished product bins, or are stockpiled in open areas by
conveyors or trucks. Other minerals such as talc or barite may require air
classification to obtain the required mesh size, and treatment by flotation to
obtain the necessary chemical purity and color.
Most non-metallic minerals require additional processing depending on the rock
type and consumer requirements. In certain cases, especially in the crushed stone
and sand and gravel industry, stone washing may be required to meet particular end
product specifications or demands such as for concrete aggregate. Some minerals,
especially certain lightweight aggregates, are washed and dried, sintered, or
treated prior to primary crushing. Others are dried following secondary crushing
or milling. Sand and gravel, crushed and broken stone, and most lightweight
aggregates normally are not milled and are screened and shipped to the consumer
after secondary or tertiary crushing. Table 3.3 lists the various unit process
3-15
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Table 3.3
Possible Sources of Emissions
Type of Plant
Crushed & Broken Stone
Sand & Gravel
Clay
Gypsum
Pumice
Feldspar
Boron
Talc
Barite
Diatomite
Lightweight Aggregate
Potash
Rock Salt
Fl uorspar
Asphalt (Gilsonite)
Sodium Compounds
Mica
Kyam'te
Pyrites
Crushers
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Screens
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Transfer
Points
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Grinders
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Loading
Operation
X
X
X
X
X
V
A
X
X
Bagging
Operation
V
X
X
•X
X
X
X
X
X
Dryers or Drilling
Calciners Operation
X
X
X
X
X
X X
X X
X
X
X
X
X
X X
-------
operations for each industry under consideration. Figures 3.1 and 3.2 show
simplified diagrams of the typical process steps required for the non-metallic
minerals investigated in this report.
3.2.2 Process Unit Operations and Their Emissions
Essentially all mining and mineral processing operations are potential sources
of particulate emissions. Emissions may be categorized as either fugitive
emissions or fugitive dust. Operations included within each category are listed in
Table 3.4. Fugitive emission sources include those sources for which emissions are
amenable to capture and subsequent control. Fugitive dust sources are not amenable
to control using conventional control systems and generally involve the
reentrainment of settled dust by wind or machine movement.
Table 3.4 EMISSION SOURCES AT NON-METALLIC MINERAL FACILTIES
Fugitive Emissions Fugitive Dust Sources
Drilling Blasting
Crushing Hauling
Screening Haul Roads
Grinding Stockpiles
Conveyor Transfer Points Plant yard
Loading Conveying
Information available on emissions from uncontrolled non-metallic minerals
processing operations is limited. Estimates developed by EPA for uncontrolled
crushed stone plant process operations are presented in Table 3.5. Based on
these estimates, fugitive emission sources alone (excluding drilling and fines
milling) emit about 5.5 kilograms of dust per megagram of material processed
3-17
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SECONDARY
CRUSHER
STOCKPILE
OR BIN
II
STOCKPILE
OR BIN
n °=
STOCKPILE
OR BIN
*3
STOCKPILE
OR BIN
04
SIZE
CLASSIFIER
Figure 3.2 General Schematic for Non-Metallic Minerals Processing
3-18
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Table 3.5
Participate Emission Factors for
Stone Crushing Process^
Process Operation Uncontrolled Emission Factor*
kg/Mg Ib/ton
Primary crushing 0.25 0.5
Secondary crushing and screening 0.75 1.5
Tertiary crushing and screening (if used) 3.0 6.0
Recrushing and screening 2.5** 5.0
Fines mill 3.0 6.0
Screening, conveying and handling 1.0 2.0
* Based on feed to the primary crusher.
** Assume 20 percent undergoes recrushing. Thus, the emission factor becomes
0.5 kg/mg (1.0 Ib/ton).
3-19
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(11 pounds per ton).
The following emission sources are discussed in detail: crushing, screening
and conveying operations, grinders, fine product loading and bagging operations.
This document will only briefly discuss mining operations.
3.2.2.1 Factors that Affect Emissions from Mining and Process Operations
In general, the factors that affect emissions from most mineral processing
operations include: the type of ore processed, the type of equipment and
operating practices employed, the moisture content of the ore, the amount of ore
processed, and a variety of geographical and seasonal factors. These factors,
discussed in more detail below, apply to both fugitive emission and fugitive dust
sources associated with mining and processing plant operation.
The type of ore (rock) processed is important. Soft rocks produce a higher
percentage of fine-grained material than do hard rocks because of their greater
friability and lower resistance to fracture.5 Thus, it is concluded that the
processing of soft rocks results in a greater potential for uncontrolled emissions
than the processing of hard rock. Major rock types arranged in order of increasinj
hardness are: talc, clay, gypsum, barite, limestone and dolomite, perlite,
feldspar, and quartz. Thus, talc could be expected to exhibit the highest
uncontrolled emissions and quartz the least.
The type of equipment and operating practices employed also affect uncon-
trolled emissions. In general, emissions from process equipment such as crushers,
screens, grinders, and conveyors depend on the size distribution of the material
and the velocity that is mechanically imparted to the material. For crushers, the
particular type of crushing mechanism employed (compression or impact) affects
emissions. The effect of equipment type on uncontrolled emissions from all sources
will be more fully discussed in subsequent sections of this report(see Sections
3.2.2.3.1 to 3.2.2.3.5).
3-20
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The inherent moisture content or wetness of the rock processed can have a
substantial effect on uncontrolled emissions. This is especially evident during
mining, initial material handling and initial plant process operation such as
primary crushing. Surface wetness causes fine particles to agglomorate or adhere
to the faces of larger stones with a resultant dust suppression effect. However,
as new fine particles are created by crushing and attrition, and as the moisture
content is reduced by evaporation, this suppressive effect diminishes and may even
disappear. Depending on the geographic and climatic conditions, the moisture
content of the mined rock ranges from nearly zero to several percent.
With regard to geographical and seasonal factors, the primary variables
affecting uncontrolled particulate emissions are wind parameters and moisture
content of the material. Wind parameters will vary with geographical location
and season and it can certainly be expected that the level of emissions from
sources which are not enclosed (principally fugitive dust sources) will be
greater during periods of high winds than periods of low winds. The moisture
content of the material will also vary with geographical location and season. It
can, therefore, be expected that the level of uncontrolled emissions from both
fugitive emission sources and fugitive dust sources will be greater in arid
regions of the country than in temperate ones and greater during the summer
months due to a higher evaporation rate.
3.2.2.2 Mining Operations
Sources of particulate emissions from mining operations include drilling,
blasting, secondary breakage and the loading and hauling of the mineral to the
processing plant. Not all non-metallic mineral deposits require drilling and
blasting to fragment portions of the deposits into pieces of material of con-
venient size for further processing. Some mineral deposits can be removed
3-21
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without blasting by the use of power equipment such as front-end loaders, drag
lines, and dredges.
Particulate emissions from drilling operations are primarily caused by the
removal of cuttings and dust from the bottom of the hole by air flushing.
Compressed air is released down the hollow drill center, forcing cuttings and
dust up and out the annular space formed between the hole wall and drill.
Blasting is used to displace solid rock from its quarry deposit and to frag-
ment it into sizes which require a minimum of secondary breakage and which can
be readily handled by loading and hauling equipment. The frequency of blasting
ranges from several shots per day to one per week depending on the plant capacity
and the size of individual shots. The effectiveness of a shot depends on the
characteristics of the explosive and the rock. Emissions from blasting are
evident from visual observations and are largely unavoidable. The emissions
generated are affected by the blasting practices employed and are reduced during
wet, low wind conditions.
If secondary breakage is required, drop-ball cranes are usually employed.
Normally, a pear-shaped or spherical drop-ball, weighing several tons, is
suspended by a crane and dropped on the oversize rock as many times as needed to
break it. Emissions are slight.
The excavation and loading of broken rock is normally performed by shovels
and front-end loaders. Whether the broken rock is dumped into a haulage vehicle
for transport or directly into the ^primary crusher, considerable fugitive dust
emissions may result. The most significant factor affecting these emissions is
the wetness of the rock.
At most quarries, large capacity "off-the-road" haulage vehicles are used to
transport broken rock from the quarry to the primary crusher over unpaved haul
3-22
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roads. This vehicle traffic on unpaved roads is responsible for a large por-
tion of the fugitive dust generated by quarrying operations. Factors affecting
fugitive dust emissions from hauling operations include the composition of the
road surface, the wetness of the road, and the volume and speed of the vehicle
traffic.
3.2.2.3 Processing Plant Facilities and Their Emissions
Principal processing plant facilities include crushers, grinders, screens,
and material handling and transfer equipment. As indicated by Table 3.4, all
these units are potential sources of particulate emissions. Emissions are
generally emitted from process equipment at feed and discharge points and from
material handling equipment at transfer points.
3.2.2.3.1 Crushing Operations
Crushing is the process by which coarse material is reduced by mechanical
energy and attrition to a desired size for mechanical separation (screening).
The mechanical stress applied to rock fragments during crushing may be accom-
plished by either compression or impact. These two methods of crushing differ
in the duration of time needed to apply the breaking force. In impacting,
the breaking force is applied very rapidly, while in compression, the rock
particle is slowly squeezed and forced to fracture. All types of crushers are
both compression and impaction to varying degrees. Table 3.6 ranks crushers
according to the predominant crushing mechanism used (from top to bottom,
compression to impaction). In all cases, there is some reduction by the rubbing
of stone on stone or on metal surfaces (attrition).
3-23
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TABLE 3.6. RELATIVE CRUSHING MECHANISM UTILIZED
BY VARIOUS CRUSHERS6
Compression Double roll crusher
Jaw crusher
Gyratory crusher
Single roll crusher
Rod mill (low speed)
Ball mill
Rod mill (high speed)
Hammermill (low speed)
Impact breaker
Impaction Hammermill (high speed)
The size of the product from compression type crushers is controlled by
the space between the crushing surfaces compressing the rock particle. This
type of crusher produces a relatively closely graded product with a small pro-
portion of fines. Crushers that reduce by impact, on the other hand, produce
a wide range of sizes and a high proportion of fines.
Since the size reduction achievable by one machine is limited, reduction in
stages is frequently required. As noted previously, the various stages include
primary, secondary, and perhaps tertiary crushing. Basically, the crushers used
in the non-metallic minerals industry are: jaw, gyratory, roll and impact
crushers.
Jaw Crushers
Jaw crushers consist of a vertical fixed jaw and a moving inclined jaw which
is operated by a single toggle or a pair of toggles. Rock is crushed by
compression as a result of the opening and closing action of the moveable jaw
against the fixed jaw. Their principal application in the industry is for
primary crushing.
3-24
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The most commonly used jaw crusher is the Balke or double-toggle type.
As illustrated in Figure 3.3, an eccentric shaft drives a Pitman arm that
raises and lowers a pair of toggle plates to open and close the moving jaw
which is suspended from a fixed shaft. In a single-toggle jaw crusher, the
moving jaw is itself suspended from an eccentric shaft and the lower part of
the jaw supported by a rolling toggle plate (Figure 3.4). Rotation of the
eccentric shaft produces a circular motion at the upper end of the jaw and
an elliptical motion at the lower end. Other types, such as the Dodge and
overhead eccentric are used on a limited scale.
The size of a jaw crusher is defined by its feed opening dimensions and
may range from about 15 x 30 centimeters to 213 x 168 centimeters (6 x 12
inches to 84 x 66 inches). The size reduction obtainable may range from
3:1 to 10:1 depending on the nature of the rock. Capacities are quite vari-
able depending on the unit and its discharge setting. Table 3.7 presents
approximate capacities for a number of jaw crusher sizes at both minimum and
maximum discharge settings.
Gyratory Crushers
Simply, a gyratory crusher may be considered to be a jaw crusher with
cricular jaws between which the material flows and is crushed. As indicated in
Table 3.8, however, a gyratory crusher has a much greater capacity than a jaw
crusher with an equivalent feed opening.
There are basically three types of gyratory crushers, the pivoted spindle,
fixed spindle and cone. The fixed and pivoted spindle gyratories are used for
primary and secondary crushing, and cone crushers for secondary and tertiary
crushing. The larger gyratories are sized according to feed opening and the
smaller units by cone diameters.
3-25
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MOVEABLE JAW
FIXED JAW
ECCENTRIC
PITMAN ARM
DISCHARGE
TOGGLES
Figure 3.3 Double-toggle Jaw Crusher
MOVEABLE JAW
FEED
FIXED
JAW
DISCHARGE
TOGGLE
Figure 3.4 Single-toggle Jaw Crusher
3-26
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Table 3.7 APPROXIMATE CAPACITIES OF JAW CRUSHERS(7)
(Discharge opening - closed)
Size
[cm. (in.)]
91
107
122
152
213
x 61
x 152
x 107
x 122
x 168
(36
(42
(48
(60
(84
x 24)
x 60)
x 42)
x 48)
x 66)
Smallest
discharge
opem
[cm.(i
>6
10.2
12.7
12.7
20.3
ng
n.)]
(3)
(4)
(5)
(5)
(8)
Capacity* Largest
[Mg/hr (tons/hr)] discharge
68
118
159
218
363
(75)
(130)
(175)
(240)
(400)
opem
[cm.(i
15.2
20.3
20.3
22.9
30.5
ng
n.)]
(6)
(8)
(8)
(9)
(12)
Capacity
[Mg/hr (tons/hr)]
145
181
250
408
544
(160)
(200)
(275)
(450)
(600)
*Based on rock weighing 100 Ib/cu ft.
Table 3.8 APPROXIMATE CAPACITIES OF GYRATORY CRUSHERS (8)
(Discharge opening - open)
Size
[cm. (in.)]
76 (30)
91 (36)
107 (42)
122 (48)
137 (54)
152 (60)
183 (72)
Smal lest
discharge
opening
[ cm . ( i n . ) ]
10.2 (4)
11.4 (4.5)
12.7 (5)
14.0 (5.5)
16.5 (6.5)
17.8 (7)
22.9 (9)
Capacity*
[Mg/hr. (tons/hr)]
181 (200)
336 (370)
381 (420)
680 (750)
816 (900)
1088 (1,200)
1814 (2,000)
Largest
discharge
opem ng
[cm. (in.)]
16.5 (6.5)
17.8 (7)
19.1 (7.5)
22.9 (9)
24.1 (9.5)
25.4 (10)
30.5 (12)
Capacity
[Mg/hr. (tons/hr)]
408 (450)
544 (600)
635 (700)
1088 (1,200)
1451 (1,600)
1814 (2,000)
2721 (3,000)
*Based on rock weighing 1600 kg/m3 (100 Ib/cu ft.)
3-27
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The pivoted spindle gyratory (Figure 3.5) has the crushing head mounted on
a shaft that is suspended from above and free to pivot. The bottom of the shaft
is seated in an eccentric sleeve which revolves, thus causing the crusher head
to gyrate in a circular path within a stationary concave circular chamber. The
crushing action is similar to that of a jaw crusher in that the crusher element
reciprocates to and from a fixed crushing plate. Because some part of the
crusher head is working at all times, the discharge from the gyratory is con-
tinuous rather than intermittent as in a jaw crusher. The crusher setting is
determined by the wide-side opening at the discharge end and is adjusted by
raising or lowering the crusher head.
Unlike the pivoted spindle gyratory, the fixed spindle gyratory has its
crushing head mounted on an eccentric sleeve fitted over a fixed shaft. This
produces a uniform crushing stroke from the top to the bottom of the crushing
chamber.
For fine crushing, the gyratory is equipped with flatter heads and con-
verted to a cone crusher (Figure 3.6). Commonly, in the lower section a
parallel zone exists. This results in a larger discharge to feed area ratio
which makes it extremely suitable for fine crushing at high capacity. Also,
unlike regular gyratories, the cone crusher sizes at the closed side setting
and not the open side (wide-side) setting. This assures that the material
discharge will have been crushed at least once at the closed side setting.
Cone crushers yield a cubical product and a high percentage of fines due to
interparticle crushing (attrition). They are the most commonly used crusher
in the industry for secondary and tertiary reduction. Table 3.9 presents
performance data for typical cone crushers.
3-28
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FEED
FIXED
THROAT'
CRUSHING SURFACE
ECCENTRIC
DRIVE
DISCHARG
Figure 3.5 The Pivoted Spindle Gyratory
FEED
CRUSHING -
SURFACES
DRIVE
DISCHARGE
ECCENTRIC
Figure 3. 6 Cone Crusher
3-29
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TABLE 3.9 PERFORMANCE DATA FOR CONE CRUSHERS9
,,. _ Capacity (Mg/hr (tons/hr))
crusher discharge setting (cm (in))
(m (ft)) KQ (3/8) 1<3 (1/2) Kg 2>5 (1) 3>8 (1>5)
0.6 (2) 18 (20) 23 (25) 23 (25)
0.9 (3) 32 (35) 36 (40) 64 (70)
1.2 (4) 54 (60) 73 (80) 109 (120) 136 150
1.7 (5.5) - - 181 (200) 250 275 308 (340)
2.1 (7) - - 229 (330) 408 450 544 (600)
Roll Crushers
These machines are utilized primarily at intermediate or final reduction
stages and are often used at portable plants. There are essentially two types,
the single-roll and the double-roll. As illustrated in Figure 3.7, the double-
roll crusher consists of two heavy parallel rolls which are turned toward each
other at the same speed. Roll speeds range from 50 to 300 rpm. Usually, one
roll is fixed and the other set by springs. Typically, roll diameters range
from 61 to 198 centimeters (24 to 78 inches) and have narrow face widths.
about half the roll diameter. Rock particles are caught between the rolls and
crushed almost totally by compression. Reduction ratios are limited and range
from 3 or 4 to 1. These units produce few fines and no oversize. They are
used especially for reducing hard stone to a final product ranging from 1/4
inch to 20 mesh.
The working elements of a single-roll crusher include a toothed or
knobbed roll and a curved crushing plate which may be corrugated or smooth.
The crushing plate is generally hinged at the top and its setting is held by
a spring at the bottom. A toothed-roll crusher is depicted in Figure 3.8
The feed, caught between the roll and crushing plate is broken by a combination
3-30
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FEED
DISCHARGE
ADJUSTABLE
ROLLS
Figure 3.7 Double-roll Crusher
FEED
TOOTH
ROLL
CRUSHING
PLATE
DISCHARGE
Figure 3.8 Single roll Crusher
3-31
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of compression, impact and shear. These units may accept feed sizes up to
51 centimeters (20 inches) and have capacities up to 454 megagrams per hour
(500 t/hr). In contrast with the double-roll, the single-roll crusher is
principally used for reducing soft materials such as limestones.
Impact Crushers
Impact crushers, including hammer mills and impactors, use the force of
fast rotating massive impellers or hammers to strike and shatter free falling
rock particles. These units have extremely high reduction ratios and produce
a cubical product spread over a wide range of particle sizes with a large pro-
portion of fines, thus making their application in industry segments such as
cement manufacturing and agstone production extremely cost effective by reducing
the need for subsequent grinding machines.
A hammermill consists of a high speed horizontal rotor with several rotor
discs to which sets of swing hammers are attached (Figure 3.9). As rock
particles are fed into the crushing chamber, they are impacted and shattered by
the hammers which attain tangential speeds as high as 76 meters (250 feet) per
second, The shattered rock then collides with a steel breaker plate and is
fragmented even further. A cylindrical grating or screen positioned at the
discharge opening restrains oversize material until it is reduced to a size
small enough to pass between the grate bars. Rotor speeds range from 250 to
1800 rpm and capacities to over 907 megagrams per hour (1,000 t/hr). Product
size is controlled by the rotor speed, the spacing between the grate bars, and
by hammer length.
An impact breaker (Figure 3.10) is similar to a hammermill except that it
has no grate or screen to act as a restraining member. Feed is broken by
impact alone. Adjustable breaker bars are used instead of plates to reflect
3-32
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FEED
BREAKER
PLATE
SWING
HAMMERS
GRATE BARS
/
DISCHARGE
Figure 3.9 Hammermill
BREAKER
PLATE
BREAKER
BARS
FEED
/
HAMMER
ROTOR
DISCHARGE
Figure 3.10 Impact Crusher
3-33
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material back into the path of the impellers. Primary-reduction units are
available which can reduce quarry run material at over 907 megagrams per hour
(1,000 t/hr) capacity to about 2.5 centimeters (1 inch). These units are not
appropriate for hard abrasive materials, but are ideal for soft rocks like
limestone.
Sources of Emissions
The generation of particulate emissions is inherent in the crushing process.
Emissions are most apparent at crusher feed and discharge points. Emissions are
influenced predominantly by the type of rock processed, the moisture content of
the rock, and the type of crusher used.
The most important element influencing emissions from crushing equipment,
as previously mentioned, is the type of rock and the moisture content of the
mineral being crushed. The crushing mechanism employed has a substantial
affect on the size reduction that a machine can achieve; the particle size
distribution of the product, especially the proportion of fines produced; and
the amount of mechanically induced energy which is imparted to fines.
Crushing units utilizing impact rather than compression produce a larger
proportion of fines as noted above. In addition to generating more fines,
impact crushers also impact higher velocity to them as a result of the fan-like
action produced by the fast rotating hammers. Because of this and the high
proportion of fines produced, impact crushers generate larger quantities of
uncontrolled particulate emissions per ton of material processed than any other
crusher type.
The level of uncontrolled emissions from jaw, gyratory, cone and roll
crushers closely parallels the reduction stage to which they are applied. As
indicated in Table 3-5, emissions increase progressively from primary to
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secondary to tertiary crushing. Factors other than the type of crushing
mechanism (compression, impact) also affect emissions. In all likelihood,
primary jaw crushers produce greater emissions than comparable gyratory because
of the bellows effect of the jaw and because gyratory crushers are usually
choke fed to minimize the open spaces from which dust may be emitted. For
subsequent reduction stages, cone crushers produce more fines as a result of
attrition and consequently generate more dust.
3.2.2.3.2 Screening Operations
Screening is the process by which a mixture of stones is separated accord-
ing to size. In screening, material is dropped into a mesh surface with open-
ings of desired size and separated into two fractions, undersize which passes
through the screen opening and oversize which is retained on the screen surface.
When material is passed over and through multiple screening surfaces, it is
separated into fractions of known particle size distribution. Screening sur-
faces may be constructed of metal bars, perforated or slotted metal plates, or
woven wire cloth.
The capacity of a screen is primarily determined by the open area of the
screening surface and the physical characteristics of the feed. It is usually
expressed in tons of material per hour per square foot of screen area. Although
screening may be performed wet or dry, dry screening is the more common.
Screening equipment commonly used in the non-metallic minerals industry
includes grizzlies, shaking screens, vibrating screens, and revolving screens.
Grizzlies
Grizzlies consist of a set of uniformly spaced bars, rods or rails. The
bars may be horizontal or inclined and are usually wider in cross section at
the top than the bottom. This prevents the clogging or wedging of stone
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particles between bars. The spacing between the bars ranges from 5 to 20
centimeters (2 to 8 inches). Bars are usually constructed of manganese steel
or other highly abrasion resistant material.
Grizzlies are primarily used to remove fines prior to primary crushing,
thus reducing the load on the primary crusher. Grizzlies may be stationary
cantilevered (fixed at one end with the discharge end free to vibrate) or
mechanically vibrated. Vibrating grizzlies are simple bar grizzlies mounted
on eccentrics (Figure 3-11). The entire assembly is moved forward and backward
at about 100 strokes a minute, resulting in better flow through and across the
grizzly surface.
Shaking Screens
The shaking screen consists of a rectangular frame with perforated plate or
wire cloth screening surfaces, usually suspended by rods or cables and inclined
at an angle of 14 degrees. The screens are mechanically shaken parallel to the
plane of material flow at speeds ranging from 60 to 800 strokes per minute and
at amplitudes ranging from 2 to 23 centimeters (3/4 to 9 inches).10 Generally,
they are used for screening coarse material, 1.3 centimeters (1/2-inch) or
larger.
Vibrating Screens
Where large capacity and high efficiency are desired, the vibrating screen
has practically replaced all other screen types. It is by far the most commonly
used screen type in the non-metallic minerals industry. A vibrating screen
(Figure 3.12) essentially consists of an inclined flat or slightly convex
screening surface which is rapidly vibrated in a plane normal or nearly normal
to the screen surface. The screening motion is of small amplitude but high
frequency, normally in excess of 3,000 cycles per minute. The vibrations may
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Figure 3.11 Vibrating Grizzly
Figure 3.12 Vibrating Screen
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be generated either mechanically by means of an eccentric shaft, unbalanced fly
wheel, cam and tappet assembly, or electrically by means of an electromagnet.
Mechanically-vibrated units are operated at about 1,200 to 1,800 rpm and
at amplitudes of about 0.3 to 1.3 centimeters (1/8 to 1/2 inch). Electrically
vibrated screens are available in standard sizes from 30 to 180 centimeters
(12 inches to 6 feet) wide and 0.76 to 6.1 meters (2-1/2 to 20 feet) long.
A complete screening unit may have one, two or three decks.
Revolving Screens
This screen type consists of an inclined cylindrical frame around which
is wrapped a screening surface of wire cloth or perforated plate. Feed material
is delivered at the upper end and, as the screen is rotated, undersized material
passes through the screen openings while the oversized is discharged at the
lower end. Revolving screens are available up to 1.2 meters (4 feet) in diam-
eter and usually run at 15 to 20 rpm.11
Source of Emissions
Dust is,emitted from screening operations as a result of the agitation of
dry material. The level of uncontrolled emissions depends on the quantity of
fine particles contained in the material, the moisture content of the material
and the type of screening equipment. Generally, the screening of fines produces
higher emissions than the screening of coarse materials. Also, screens agi-
tated at large amplitudes and high frequency emit more dust than those operated
at small amplitudes and low frequencies.
3.2.2.2.2 Conveying Operation
Materials handling devices are used to convey materials from one point to
another. The most common include feeders, belt conveyors, bucket elevators,
screw conveyors, and pneumatic systems.
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Feeders
Feeders are relatively short, heavy-duty conveyance devices used to re-
ceive material and deliver it to process units, especially crushers, at a uni-
form regulated rate. The various types used are the apron, belt, reciprocating
plate, vibrating, and wobbler feeders.
Apron feeders are composed of overlapping metal pans or aprons which are
hinged or linked by chains to form an endless conveyor supported by rollers
and spaced between a head and tail assembly. These results are constructed to
withstand high impact and abrasion and are available in various widths (18 to
27 inches) and lengths.
Belt feeders are essentially short, heavy duty belt conveyors equipped
with closely spaced support rollers. Adjustable gates are used to regulate
feed rates. Belt feeders are available in 46 to 122 centimeter (18 to 48 inch)
widths and 0.9 to 3.7 meter (3 to 12 foot) lengths and are operated at speeds
of 12.2 to 30.5 meters (40 to 100 feet) per minute.
Reciprocating plate feeders consist of a heavy-duty horizontal plate which
is driven in a reciprocating motion causing material to move forward at a uni-
form rate. The feed rate is controlled by adjusting the frequency and length
of the stroke.
Vibrating feeders operate at a relatively high frequency and low amplitude.
Their feed rate is controlled by the slope of the feeder bed and the amplitude
of the vibrations. These feeders are available in a variety of sizes, capa-
cities and drives. When combined with a grizzly, both scalping and feeding
functions are performed.
Wobbler feeders also perform the dual task of scalping and feeding. These
units consist of a series of closely spaced elliptical bars which are
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mechanically rotated, causing oversize material to tumble forward to the dis-
charge and undersize material to pass through the spaces. The feed rate is
controlled by the bar spacing and the speed of rotation.
Belt Conveyors
Belt conveyors are the most widely used means of transporting, elevating
and handling materials in the non-metallic minerals industry. As illustrated
in Figure 3.13, belt conveyors consist of an endless belt which is carried on
a series of idlers usually arranged so that the belt forms a trough. The belt
is stretched between a drive or head pulley and a tail pulley. Although belts
may be constructed of other material, reinforced rubber is the most commonly
used. Belt widths may range from 36 to 152 centimeters {14 to 60 inches} with
76 to 91 centimeter (30 to 36 inch) belts the most common. Normal operating
speeds may range from 60 to 120 meters per minute (200 to 400 feet/minute).
Depending on the belt speed, belt width and rock density, load capacities may
be in excess of 1360 megagrams (1,500 tons) per hour.
HEAD
PULLEY
IDLER
TAIL
PULLEY
Figure 3.13 Conveyor Belt Transfer Point
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Elevators
Bucket elevators are utilized where substantial elevation is required
within a limited space. They consist of a head and foot assembly which sup-
ports and drives an endless single or double strand chain or belt to which
buckets are attached. Figure 3.14 depicts the three types most commonly used:
the high-speed centrifugal-discharge, the slow speed positive or perfect-
discharge, and the continuous-bucket elevator.
The centrifugal-discharge elevator has a single strand of chain or belt
to which the spaced buckets are attached. As the buckets round the tail pulley,
which is housed within a suitable curved boot, the buckets scoop up their load
and elevate it to the point of discharge. The buckets are so spaced so that
at discharge, the material is thrown out by the centrifugal action of the
bucket rounding the head pulley. The positive-discharge type also utilizes
spaced buckets but differs from the centrifugal type in that it has a double-
strand chain and a different discharge mechanism. An additional sprocket,
set below the head pulley, effectively bends the strands back under the pulley
causing the bucket to be totally inverted resulting in a positive discharge.
The continuous-bucket elevator utilizes closely spaced buckets attached
to single or double strand belt or chain. Material is loaded directly into
the buckets during ascent and is discharged gently as a result of using the
back of the precluding bucket as a discharge chute.
Screw Conveyors
Screw conveyors are comprised of a steel shaft with a spiral or helical
fin which, when rotated, pushes material along a trough. Since these con-
veyors are usually used with wet classification, no significant emission prob-
lem is experienced.
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(a)
(b)
(c)
LEGEND
(a) centrifugal discharge
(b) positive discharge
(c) continuous discharge
Figure 3.14. Bucket Elevator Types
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Pneumatic Conveyors
Pneumatic conveyors are comprised of tubes or ducts through which material
is conveyed. Pneumatic conveyors are divided into two classes termed by their
operating principles: pressure systems and vacuum (suction) systems.
Pressure systems are further classified into low pressure and high pressure
types, and vacuum systems into low-, medium-, and high vacuum types. Pressure
and vacuum systems occasionally are used in combination for special requirements
Pressure systems operate at pressure obtainable from a fan (low-pressure
systems) or a compressed air system (high-pressure systems). Normally, the
airstream functions in a 20 to 31 centimeter (8 inch to 12 inch) diameter pipe-
line. Into this line, material is fed from a hopper or other device at con-
trolled rates. The airstream immediately suspends this material and conveys
it to a cyclone-type or filter-type collector for deposit. Conveying air es-
capes via the cyclone vent or through the filter.
Vacuum systems offer the advantage of clean, efficient pickup from rail-
cars, trucks or bins for unloading or in-plant conveying operations. Cyclone
receivers or combination receiver-filters are used at the terminal of the sys-
tem to separate the material being conveyed from the air. Below the receiver,
either a rotary feeder or gatelock (trap door feeder) is employed as a dis-
charge air lock. Positive displacement blowers are used as exhausters to
provide the necessary conveying air at the operating vacuum. Generally, the
vacuum system is most applicable where the feed-in point must be flexible,
such as unloading railroad cars, barges, ships, or reclaiming material from
open warehouse storage, or where it is desirable to pick up material from a
multiplicity of stations.
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Source of Emissions
Particulates may be emitted from any of the material handling and transfer
operations. As with screening, the level of uncontrolled emissions depends on
the material being handled, the size of the material handled, the degree of
agitation of the material and the moisture content of the material. Perhaps
the largest emissions occur at conveyor belt transfer points. Depending
on the conveyor belt speed and the free fall distance between transfer points,
substantial emissions may be generated
3.2.2.3.4 Grinding Operation
Grinding is a further step in the reduction of material to particle sizes
smaller than those attainable by crushers. Because the material to be treated
has already been reduced to small sizes, and the force to be applied to each
particle is comparatively small, the machines used in grinding are of a dif-
ferent type, and may operate on a different principle, from those used in more
coarse crushing.
As with crushers, the most important element influencing emissions from
grinding mills is the reduction mechanism employed, compression or impact.
Grinding mills generally utilize impact rather than compression. Reduction
by impact will produce a larger proportion of fines. Particulate emissions
are generated from grinding mills at the grinder's inlet and outlet. Gravity
type grinding mills accept feed from a conveyor and discharge product into a
screen or classifier or onto a conveyor. These transfer points are the source
of particulate emissions. The outlet has the highest emissions potential
because of the finer material. Air-swept mills include an air conveying sys-
tem and an air separator, a classifier, or both. The air separator and
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and classifier are generally cyclone collectors. In some systems, the air
just conveys the material to a separator for deposit into a storage bin with
the conveying air escaping via the cyclone vent. In other grinding systems,
the air is continuously recirculated. Maintaining this circulating air sys-
tem under suction keeps the mill dustless in operation, and any surplus air
drawn into the system due to the suction created by the fan is released through
a vent. In both cases the vent gases will contain a certain amount of par-
ti cul ate matter.
The levels of uncontrolled emissions from grinding mills (fine mills) are
indicated in Table 3-5.
Many types of grinding mills are manufactured for use by various industries,
The principal types of mills used are: (1) hammer, (2) roller, (3) rod,
(4) pebble and ball, and (5) fluid energy. Each of these types of mills is
discussed separately below.
Hammermills
A hammermill consists of a high speed horizontal rotor with several rotor
discs to which sets of swing hammers are attached. As rock particles are fed
into the grinding chamber, they are impacted and shattered by the hammers which
attain peripheral speeds greater than 4,572 meters per minute (250 feet per
second). The shattered rock then collides with a steel breaker plate and is
fragmented even further. A cylindrical grating or screen positioned at the
discharge opening restrains oversize material until it is reduced to a size
small enough to pass between the grate bars. Product size is controlled by
the rotor speed, the spacing between the grate bars, and by hammer length.
These mills are used for nonabrasive materials and can accomplish a size re-
duction of up to 12:1.
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Roller Mill
The roller mill, also known as a Raymond Roller Mill, with its integral
whizzer separator can produce ground material ranging from 20 mesh to 325 mesh
or finer. The material is ground by rollers that travel along the inside of
a horizontal stationary ring. The rollers swing outward by centrifugal force,
and trap the material between them and the ring. The material is swept out of
the mill by a stream of air to a whizzer separator, located directly on top of
the mill, where the oversize is separated and dropped back for further grinding
while the desired fines pass up through the whizzer blades into the duct lead-
ing to the air separator (cyclone). A typical roller mill is shown in
Figure 3.15.
Rod Mill
The rod mill is generally considered as a granular grinding unit, prin-
cipally for handling a maximum feed size of 2 to 4 centimeters (1 to 2 inches),
and grinding to a maximum of 65 mesh. It is normally used in a closed circuit
with a sizing device, such as classifiers or screens, and for wet or dry grind-
ing. It will grind with the minimum of the finer sizes, such as 100 or 200
mesh, and will handle relatively high moisture material without packing.
The mill in its general form consists of a horizontal, slow-speed, rotating,
cylindrical drum. The grinding media consists of a charge of steel rods,
slightly shorter than the mill's inside length and from 5 to 13 centimeters
(2 inches to 5 inches) in diameter. The rods roll freely inside the drum during
its rotation to give the grinding action desired.
Pebble and Ball Mills
The simplest form of a ball mill is cylindrical, horizontal, slow-speed
rotating drum containing a mass of balls as grinding media. When other types
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A Product outlet
— -Revolving
whizzers
- Whizzer
drive
Grinding ring
Grind ing roller
-Feeder
Figure 3.15. Roller Mill
3-47
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of grinding media such as a flint or various ceramic pebbles are used, it is
known as a pebble mill. The ball mill uses steel, flint, porcelain, or cast
iron balls. A typical ball mill is shown in Figure 3.16.
The diameter of balls or pebbles as the initial charge in a mill is
determined by the size of the feed material and the desired fineness of the
product. Usually the larger diameter ranges are used for preliminary grinding
and the smaller for final grinding. Ball mills reduce the size of the feed
mostly by impact. These grinders normally have a speed of 10 to 40 revolutions
per minute. If the shell rotates too fast, centrifugal force keeps the balls
against the shell and minimal grinding occurs.
Fluid Energy Mills
When the desired material size is in the range of 1 to 20 microns, an
ultrafine grinder such as the fluid energy mill is required. A typical fluid
energy mill is shown in Figure 3.17. In this type of mill, the particles are
suspended and conveyed by a high velocity gas stream in a circular or elliptical
path. Size reduction is caused by impaction and rubbing against mill walls,
and by interparticle attrition. Classification of the particles takes place
at the upper bend of the loop shown in Figure 3.17. Internal classification
occurs because the smaller particles are carried through the outlet by the gas
stream while the larger particles are thrown against the outer wall by centrif-
ugal force. Product size can be varied by changing the gas velocity through
the grinder.
Fluid energy mills can normally reduce up to 0.91 megagrams/hr (1 t/hr)
of solids from 0.149 mm (100 mesh) to particles averaging 1.2 to 10 microns
in diameter. Typical gas requirements are 0.45 and 1.8 kg (1 to 4 pounds) of
steam or 2.7 to 4.1 kg (6 to 9 pounds) of air admitted at about 6.8 atm
3-48
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REVOLVING
SHELL
— DRIVE GEAR
FEED-
PRODUCT
OUTLET
Figure 3.16. Ball Mill
REDUCTION
CHAMBER
SIZED
/PARTICLES
FEED
AIR OR STEAM INLET
NOZZLES
Figure 3.17. Fluid-energy Mill
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(100 psig) per 0.45 kg (1 pound) of product. The grinding chambers are about
2.5 to 20 cm (1 to 8 inches) in diameter and the equipment is 1.2 to 2.4 meters
(4 to 8 feet) high.
3.2.2.7 Separating and Classifying
Mechanical air separators of the centrifugal type cover a distinct field
and find wide acceptance for the classification of dry materials in a relatively
fine state of subdivision. In commercial practice the separator may be said
to begin where the impact of vibrating screens leave off,12 extending from
about 40 to 60 mesh down.
Briefly stated, the selective action of the centrifugal separator is the
result of an ascending air current generated within the machine by means of a
fan, such current tending to lift the finer particles against the combined
effect of centrifugal force and gravity. In operation the feed opening allows
the material to drop on the lower or distributing plate where it is spread and
thrown off by centrifugal force, the larger and heavier particles being pro-
jected against an inner casing, while the smaller and lighter particles are
picked up by the ascending air current created by the fan. These fines are
carried over into an outer cone and deposited. Concurrently, the rejected
coarse material drops into the inner cone, passes out through a spout and is
recycled back to the grinding mill.
The air, after dropping the major portion of its burden, is either re-
circulated back to the grinding mill or vented. In the case of the recir-
culated air, a small amount of extraneous air is entrained in the feed and
frequently builds up pressure in the separator, in which case the excess air
may be vented off. Both vent gases are a source of particulate matter.
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3.2.2.3.5 Bagging and Bulk Loading Operations
In the non-metallic minerals industry the valve type paper bag, either
sewn or pasted together, is widely used for shipping fine materials. The valve
bag is "factory closed," that is, the top and bottom are closed either by sewing
or by pasting, and a single small opening is left on one corner. Materials are
discharged into the bag through the valve. The valve closes automatically due
to the internal pressure of the contents of the bag as soon as it is filled.
The valve type bag is filled by means of a packing machine designed
specifically for this purpose. The material enters the bag through a nozzle
inserted in the valve opening, and the valve closes automatically when the
filling is completed.
Bagging operations are a source of particulate emissions. Dust is emitted
during the final stages of filling when dust laden air is forced out of the bag.
The fugitive emissions due to bagging operation are generally localized in the
area of the bagging machine.
Fine product materials that are not bagged for shipment are either bulk
loaded in tank trucks or enclosed railroad cars. The usual method of loading
is gravity feeding through plastic or fabric sleeves. Bulk loading of fine
material is a source of particulate because, as in the bagging operation, dust
laden air is forced out of the truck or railroad car during the loading
operation.
3.2.3 Emissions Under Existing Regulations
Existing State regulations applicable to the non-metallic minerals industry
take many forms, depending on whether emissions are process or fugitive in
nature. Regulations limiting particulate emissions from process sources are
based on general process weight, concentration and/or visible emission regulations
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For a 45 megagrams per hour (50 t/hr) plant, typical process weight regulations
would limit allowable emissions from each process step (i.e., crushing, grinding,
drying) to 25.6 kg/hr (56.4 Ib/hr). This is about 95 percent reduction in un-
controlled emissions. For a typical 454 megagrams per hour (500 t/hr) crushing
plant, most stringent and least stringent process weight regulations would limit
allowable emissions to 18.2 and 120 kg/hr (40.0 and 264.0 Ib/hr), respectively.
The most stringent regulations, such as Pennsylvania's, limit emission from a
collection device to 0.09 g/dscm (0.04 gr.dscf) and in some cases to as low as
0.046 g/dscm (0.02 gr/dscf).14
Fugitive dust regulations are for the most part subjective and vague.
Most suggest that reasonable precautions be taken for control, but provide no
means of determining compliance. Some states prohibit fugitive dust or emis-
sions from any source from crossing property boundaries either by disallowing
and visible emissions or limiting them with an ambient concentration standard.
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REFERENCES
1. Minerals Yearbook (1972), Volume I, Bureau of Mines.
2. Development Document for Interim Final Effluent Limitations Guidelines
and New Source Performance Standards for the Mineral Mining and Pro-
cessing Industry, U.S. Environmental Protection Agency, October 1975.
3. Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines.
4. Compilation of Air Pollution Emission Factors, Second Edition, U.S.
Environmental Protection Agency, Publication No. AP-42, April 1973,
p. 8.20-1.
5. Characterization of Particulate Emissions from the Stone-Processing
Industry, Research Triangle Institute, EPA Contract No. 68-02-0607,
May 1975, p. 57.
6. Pit and Quarry Handbook and Purchasing Guide. 63rd Edition, Pit and
Quarry Publications, Incorporated, Chicago, 1970, p. B-17.
7. Reference 6.
8. Reference 6.
9. Perry, Robert H. (editor), Chemical Engineers Handbook, 3rd Edition,
McGraw-Hill, New York, 1950, p. 1127.
10. Reference 8, p. 956.
11. Reference 5, p. B-144.
12. Reference 5, p. B-73.
13. Analysis of Final State Implementation Plans-Rules and Regulations,
prepared by the MITRE Corporation for the U.S. Environmental Protection
Agency, Contract No. 68-02-0248, July 1972.
14. Title 25. Rules and Regulations, Pennsylvania Department of Environ-
mental Resources, pages 123.2-123.3.
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4. EMISSION CONTROL TECHNIQUES
The diversity of the participate emission sources involved in mining
and processing non-metallic minerals requires use of a variety of
control methods and techniques. Dust suppression techniques, designed to
prevent particulate matter from becoming airborne, are applicable to both
fugitive process and fugitive dust sources. Where particulate emissions can
be contained and captured, particulate collection systems are used. Emission
sources and applicable control options are listed in Table 4.1.
This chapter discusses the control technology applicable to the follow-
ing process operations at non-metallic minerals plants: crushers, grinders,
screens, conveyor transfer points, storage bins, and fine products loading
and bagging.
4.1 CONTROL OF PLANT PROCESS OPERATIONS
A representative non-metallic mineral processing plant, consisting of
crushers; grinders; screens; conveyor transfer points; and storage, loading
and bagging facilities, contains a multiplicity of dust-producing points.
Therefore, effective emission control can present a number of problems. Methods
utilized to reduce emissions include wet dust suppression, dry collection,
and a combination of the two. Wet dust suppression consists of introducing
moisture into the material flow, causing fine particulate matter to be
confined and remain with the material flow rather than becoming airborne.
Dry collection involves hooding and enclosing dust-producing points and
exhausting emissions to a collection device. Combination systems utilize
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Table 4.1. PARTICULATE EMISSION SOURCES FOR
THE EXTRACTION AND PROCESSING OF NON-METALLIC MINERALS
Operation or Source
Control Options
Drilling
Blasting
Loading (at mine)
Hauling
Crushing
Screening
Conveying (transfer points)
Stockpiling
Grinding
Storage Bins
Conveying (other than
transfer points)
Windblown dust from
stockpiles
Windblown dust from roads
and plant yard
a)
b)
a)
b)
c)
d)
e)
a)
b)
a)
b)
c)
d)
a)
b)
a)
b)
c
d
a
b
c
d
e
f)
Liquid injection (water or
water plus a wetting agent)
Capturing and venting emissions to
a control device
Adopt good blasting practices
Water wetting
Water wetting of haulage roads
Treatment of haulage roads with
surface agents
Soil stabilization
Paving
Traffic control
Wet dust suppression systems
Capturing and venting
emissions to a control device
Same as crushing
Same as crushing
Stone ladders
Stacker conveyors
Water sprays at conveyor
discharge
Pugmill
Same as crushing
Capturing and Venting
to a control device
Covering
Wet dust suppression
Water wetting
Surface active agents
Covering (i.e., silos, bins)
Windbreaks
Water wetting
Oiling
Surface active agents
Soil stabilization
Paving
Sweeping
4-2
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Table 4.1 (Continued)
Operation or Source
Control Options
Loading (product into RR a)
cars, trucks, ships) b)
Bagging a)
Magnetic Separation a)
Wetting
Capturing and venting
to control device
Capturing and venting
to control device
Capturing and Venting
to control device
Does not include processes involving combustion
4-3
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both methods at different stages throughout the processing plant. In
addition to these control techniques, the use of enclosed structures to
house process equipment may also be effective in preventing emissions to
the atmosphere.
4.1.1 Wet Dust Suppression
In a wet dust suppression system, dust emissions are controlled by
applying moisture in the form of water or water plus a wetting agent sprayed
at critical dust producing points in the process flow. This causes dust
particles to adhere to larger mineral pieces or to form agglomerates too
heavy to become or remain airborne. Thus, the objective of wet dust
suppression is not to fog an emission source with a fine mist to capture and
remove particulates emitted, but rather to prevent their emission by keeping
the material moist at all process stages.
The wet dust suppression method has been used on a wide variety of stone
including limestone, traprock, granite, shale, dolomite, and sand and gravel.
It can be generally considered to have a universial application to stone
handled through a normal crushing and screening operation. In some
cases, however, watersprays cannot be used since the moisture may interfere
with further processing such as crushing, screening or grinding where
blinding problems may occur. In addition, the capacity of the dryers
used in some of the processing steps limits the amount of water that can be
sprayed onto the raw materials. Once the materials have passed through the
drying operations, water cannot be added and other means of dust control must
be utilized.
When plain or untreated water is used, because of its unusually high
surface tension (72.75 dynes/cm2 at 20°C), the addition of 5 to 8 percent
4-4
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moisture (by weight), or greater, may be required to adequately suppress
dust. In many installations this may not be acceptable because excess
moisture may cause screening surfaces to blind, thus reducing both their
capacity and effectiveness, or result in the coating of mineral surfaces
yielding a marginal or non-specification product. To counteract these
deficiencies, small quantitites of specially formulated wetting agents or
surfactants are blended with the water to reduce its surface tension and
consequently improve its wetting efficiency so that dust particles may
be suppressed with a minimum of added moisture. Although these agents
may vary in composition, their molecules are characteristically composed
of two groups, a hydrophobic group (usually a long chain hydrocarbon) and
a hydrophylic group (usually a sulfate, sulfonate, hydroxide or ethylene
oxide). When introduced into water, these agents effect an appreciable
2 2
reduction in its surface tension (to as low as 27 dynes/cm ). The
dilution of such an agent in minute quantities of water (1 part wetting
agent to 1,000 parts water) is reported to make dust control practical
throughout an entire crushing plant. In a crushed stone plant, this may
amount to as little as 1/2 to 1 percent total moisture per ton of stone
processed.
In adding moisture to the process material, several application
points are normally required. Since the time required for the proper
distribution of the added moisture on the mineral is critical to
achieving effective dust control, treatment normally begins as soon as
possible after the material to be processed is introduced into the plant.
As such, the initial application point is commonly made at the primary
4-5
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crusher truck dump. In addition to introducing moisture prior to
processing, this application contributes to reducing intermittent
dust emissions generated during dumping operations. Spray bars located
either on the periphery of the dump hopper or above it are used.
Applications are also made at the discharge of the primary crusher and at
all secondary and tertiary crushers where new dry surfaces and dust
are generated by the fracturing of stone. In addition, treatment may
also be required at feeders located under surge or reclaim piles if this
temporary storage results in sufficient evaporation. Further wetting
of the material at screens, conveyor transfer points, conveyor and
screen discharges to bins, and conveyor discharges to storage piles may
or may not be necessary because, if properly conditioned at application
points, the wetted material exhibits a carryover dust control effect
that may suppress the dust through a number of material handling
operations. The amount of moisture required at each application point
is dependent on a number of factors including the wetting agent used,
its dilution ratio in water, the type and size of process equipment
and the characteristics of the material processed (type, size distribution,
feed rate and moisture content).
A typical wet dust suppression system, such as the Chem-Jet System9
manufactured by the Johnson-March Corporation and illustrated in
Figure 4.1, contains a number of basic components and features including:
(1) a dust control agent (compound M-R); (2) proportioning equipment;
The use of trade names or commercial products does not
constitute endorsement or recommendation for use by the
Environmental Protection Agency.
4-6
-------
TRUCK DUMP
INCOMING WATER LINE
COMPOUND M R DRUM
PROPORTIONER
Figure 4.1. Wet dust suppression system.
4
-------
(3) a distribution system; and (4) control actuators. A proportioner and
pump are necessary to proportion the wetting agent and water at the
desired ratio and to provide moisture in sufficient quantity and at
adequate pressure to meet the demands of the overall system.
Distribution is accomplished by spray headers fitted with pressure
spray nozzles. One or more headers are used to apply the dust suppressant
mixture at each treatment point at the rate and spray configuration
required to effect dust control. A variety of nozzle types may be used
including hollow-cone, solid cone or fan nozzles, depending on the spray
pattern desired. To prevent nozzle plugging, screen filters are used.
Figure 4.2 shows a typical arrangement for the control of dust emissions at
a crusher discharge.
Spray actuation and control is important to prevent waste and
undesirable muddy conditions, especially when the material flow is
intermittent. Spray headers at each application point are normally
equipped with an on-off controller which is interlocked with a sensing
mechanism so that sprays will be operative only when there is material
actually flowing. In addition, systems are sometimes designed to operate
under all weather conditions. To provide protection from freezing,
exposed pipes are usually traced with heating wire and insulated. When
the system is not in use, it should be drained to insure that no water
remains in the lines. During periods of prolonged cold weather when
temperatures remain below 0°C, wetted raw materials will freeze into
large blocks and adhere to cold surfaces such as hopper walls. Additional
labor may be required to prevent such build-ups.
4-8
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SUPPRESSANT
FILTER
CONTROL
VALVE
BELT
IDLERS
Figure 4.2. Dust suppression application
at crusher discharge.
4-9
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At a rock crushing plant with a well designed wet dust suppression
system, the Johnson-March Corporation claims that better than 90 percent
control efficiency is attainable for the emissions including all process
5
operations from the primary crusher to stockpile and reclaim. Since
these emissions are unconstrained and not amenable to testing, no actual
particulate emission measurements have been made to verify or dispute
this contention.
4.1.2 Dry Collection Systems
Particulate emissions generated at plant process operations (crushers,
screens, grinders, conveyor transfer points, fine product loading
operations and bagging operations) may be controlled by capturing and
exhausting potential emissions to a collection device. Depending on the
physical layout of the plant, emission sources may be either manifolded
to a single centrally located collector or ducted to a number of
individual control units. Collection systems consist of an exhaust
system utilizing hoods and enclosures to capture and confine emissions,
ducting and fans to convey the captured emissions to a collection device,
and the collection device for particulate removal prior to exhausting
the air stream to the atmosphere.
4.1.2.1 Exhaust Systems and Ducting
If a collection system is to effectively prevent particulate emissions
from being discharged to the atmosphere at the locations where emissions
are generated, local exhaust systems including hooding and ducting must
be properly designed and balanced. (Balancing refers to adjusting the
static pressure balance, which exists at the junction of two branches, to
obtain the desired volume in each branch.) Process equipment should be
4-10
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enclosed as completely as practicable, allowing for access for operation,
routine maintenance and inspection requirements. For crushing facilities,
recommended hood capture velocities range from 61 to 150 meters (200 to
500 feet) per minute. ' In general, a minimum indraft velocity of 61
meters (200 feet) per minute should be maintained through all open hood
areas. Proper design of hoods and enclosures will minimize exhaust volumes
required and, consequently, power consumption. In addition, proper
hooding will minimize the effects of cross drafts (wind) and the effects
of induced air (i.e., air placed in motion as a result of machine movement
or falling material). A well designed enclosure can be defined as a
housing which minimizes open areas between the operation and the hood
and contains all dust dispersion action.
Good duct design dictates that adequate conveying velocities be
maintained so that the transported dust particles will not settle in the
ducts along the way to the collection device. Based on information for
crushed stone, conveying velocities recommended for mineral particles
range from 1,100 to 1,400 meters/min. (3,500 to 4,500 fpm).8'9
Adequate design and construction specifications are available and
have been utilized to produce efficient, long-lasting systems. Various
guidelines establishing minimum ventilation rates required for the control
of crushing plant operations, and upon which the ventilation rates most
commonly utilized in the industry are based, are briefly discussed below.
4-11
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4.1.2.1.1 Crushers and Grinders
Hooding and air volume requirements for the control of crusher and
grinder emissions are quite variable depending upon the size and shape
of the emission source, the hood's position relative to the points of
emission, and the velocity, nature, and quantity of the release particles.
The only established criterion is that a minimum indraft velocity of 61
meters per minute (200 fpm) be maintained through all open hood areas. To
achieve this, capture velocities in excess of 150 meters per minute (500
fpm) may be necessary to overcome induced air motion, resulting from the
material feed and discharge velocities and the mechanically induced
velocity (fan action) of a particular equipment type. To achieve
effective emission control, ventilation should be applied at both the
upper portion, or feed end, of the equipment and at the discharge point.
An exception to this would be at primary jaw or gyratory crushers because
of the necessity to have ready access to get at and dislodge large rocks
which may get stuck in the crusher feed opening. Where access to a device
is required for maintenance, removable hood sections may be utilized.
In general, the upper portion of the crusher or grinder should
be enclosed as completely as possible, and exhausted according to the
criteria established for .transfer points (see Section 4.1.2.1.3).
The discharge to the transfer belt should also be enclosed as completely
as possible. The exhaust rate varies considerably depending on crusher
4-12
-------
type. For impact crushers or grinders, exhaust volumes may range from
110 to 230 m3/min. (4,000 to 8,000 cfm).11 For compression type crushers,
an exhaust rate of 46 m /min per meter (500 cfm per foot) of discharge
12
opening should be sufficient. The width of the discharge opening will
approximate the width of the receiving conveyor. For either impact
crushers or compression type crushers, pick-up should be applied down-
stream of the crusher for a distance of at least 3.5 times the width of
13
the receiving conveyor. A typical hood configuration used to control
particulate emissions from a cone crusher is depicted in Figure 4.3
Grinding or milling circuits which employ air conveying systems
operate at slightly negative pressure to prevent the escape of air
containing the ground rock. Because the system is not airtight, some
air is drawn into the system and must be vented. This vent stream can
be controlled by discharging it through a control device.
4.1.2.1.2 Screens
A number of exhaust points are usually required to achieve
effective control at screening operations. A full coverage hood, as
depicted in Figure 4.4, is generally used to control emissions generated
at actual screening surfaces. Required exhaust volumes vary with the
surface area of the screen and the amount of open area around the
periphery of the enclosure. A well-designed enclosure should have a
space of no more than 5 to 10 centimeters (2 to 4 inches) around the
3
periphery of the screen. A minimum exhaust rate of 15 m /min. per square
meter (50 cfm per square foot) of screen area is commonly used with no
14
increase for multiple decks. Additional ventilation air may be
4-13
-------
EXH<\'JST
CRUSHER
DISCHARGED.
CONE
CRUSHER
FAN
Figure 4.3'. Hood configuration used to control a cone crusher.
-------
TO CONTROL
DEVICE
FEED
COMPLETE
ENCLOSURE
SCREEN
THROUGHS
Figure 4.4 Hood configuration for
vibrating screen.
4-15
-------
required at the discharge chute to belt or bin transfer points. If
ventilation is needed, these points are treated as regular transfer
points and exhausted accordingly. (See Section 4.1.2.1.3).
4.1.2.1.3 Conveyor Transfer Points
At belt to belt conveyor transfer points, hoods should be
designed to enclose both the head pulley of the upper belt and the tail
pulley of the lower belt as completely as possible. With careful
design, the open area should be reduced to about 0.15 square meters per
meter (0.5 square feet per foot) of belt width. Factors affecting the
air volume to be exhausted include the conveyor belt speed and the
free-fall distance to which the material is subjected. Recommended
2
exhaust rates are 33 m- per min. per meter (350 cfm per foot) of belt
width for belt speeds less than 61 meters/min. (200 fpm) and 150
meters /min (500 cfm) for belt speeds exceeding 61 meters/min (200
fpm). For a belt to belt transfer with less than a 0.91 meter
(three foot) fall, the enclosure illustrated in Figure 4.5 is commonly
used.
For belt to belt transfers with a free-fall distance greater than
0.91 meters (three feet) and for chute-to-belt transfers, an arrangement
similar to that depicted in Figure 4.6 is commonly used. The exhaust
connection should be made as far downstream as possible to maximize dust
fallout and thus minimize needless dust entrainment. For very dusty
4-16
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T° I r-i
CONTROL 1
DEVICE II 45'
2" CLEARANCE FOR LOAD
ON BELT
DETAIL OF BELT OPENING
CONVEYOR TRANSFER LESS THAN
3' FALL. FCW GREATER FALL
PROVIDE ADDITIONAL EXHAUST AT
LOWER BELT SEE DETAIL AT RIGHT
Figure 4.5 Hood configuration for conveyor transfer,
less than 0.91 meter (3-foot) fall.
material, additional exhaust air may be required at the tail pulley of
o
the receiving belt. Recommended air volumes are 20 m /min (700 cfm)
for belts 0.91 meters (three feet) wide and less, and 28 m /min (1,000
cfm) for belts wider than 0.91 meters (three feet).
Belt or chute-to-bin transfer points differ from the usual transfer
operation in that there is no open area downstream of the transfer point,
Thus, emissions are emitted only at the loading point. As illustrated
4-17
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FROM CHUTE
OR BELT
TO CONTROL
DEVICE
ADDITIONAL
EXHAUST
RUBBER
SKIRT
CONVEYOR BELT
Figure 4.6 Hood configuration for a chute to belt
or conveyor transfer, greater than 0.91
meters (3-foot) fall.
4-18
-------
in Figure 4.7, the exhaust connection is normally located at some
point remote from the loading point and exhausted at a minimum rate
of 61 m /min per square meter (200 cfm per square foot) of open area.
BEL
TO
LOADING 5
, POINT
' C
T ( }
\ / /
BIN
OR
HOPPER
CONTRC
EVICE
^=
\
Figure 4»7. Exhaust configuration at bin or hopper.
4.1.2.1.4 Product Loading and Bagging
Particulate emissions from truck and railcar loading of coarse
material can be minimized by reducing the open height that the material
must fa.ll from the silo or bin to the shipping vehicle. Shrouds, telescoping
feed tubes, and windbreaks can further reduce the fugitive emissions
from this intermittent source. Particulate emissions from loading of fine
material into either trucks or railroad car can be controlled by an exhaust
system vented to a fabric filter system. The system is similar to the
4-19
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system described above for controlling bin or hopper transfer points
(see Figure 4.7). The material is fed through one of the vehicle's
openings and the exhaust connection is normally at another opening. The
system should be designed with a minimum amount of open area around the
periphery of the feed chute and the exhaust duct.
Bagging operations are controlled by local exhaust systems and
vented to a fabric filter system for product recovery. Hood face
velocities on the order of 150 meters (500 feet) per minute should be
used. An automatic bag filling operation and vent system is shown in
Figure 4.8.
500 fpm maximum
Hood attached to bin
Principal dust source
Scale support
Figure 4-8. Bag filling vent system.
19
4-20
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4.1.2.2 Collection Devices
The most efficient dust collection device used in the non-metallic
mineral industry is the fabric filter or baghouse. For most crushing
plant applications, mechanical shaker type collectors which require
periodic shutdown for cleaning (after four or five hours of operation)
are used. These units are normally equipped with cotton sateen bags and
operated at an air-to-cloth ratio of 2 or 3 to 1. A cleaning cycle
usually requires no more than two to three minutes of bag shaking and is
normally actuated automatically when the exhaust fan is turned off.
For applications where it may be impractical to turn off the
collector, fabric filters with continuous cleaning are employed. Although
compartmented mechanical shaker types may be used, jet pulse units are
predominately used by the industry. These units usually use wool or
synthetic felted bags for a filtering media and may be operated at a
filtering ratio of as high as 6 or 10 to 1. Regardless of the baghouse
type used, jet pulse or shaker, greater than 99 percent efficiency can
20
be attained even on submicron particle sizes. Two baghouses tested
by EPA for both inlet and outlet emission levels had collection
21 22
efficiencies of 99.8 percent. '
Other collection devices used in the industry include cyclones and low
energy scrubbers. Although these collectors may demonstrate efficiencies
of 95 to 99 percent, for coarse particles (40 microns and larger),
their efficiencies are poor, less than 85 percent, for medium and fine
23
particles (20 microns and smaller). Although high energy scrubbers
and electrostatic precipitators could conceivably achieve results
similar to that of a fabric filter, these methods are not commonly used
to control dust emissions in the industry.
4-21
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4.1.2.2.1 Fabric Filters
Fabric filters are high efficiency collection devices used quite exten-
sively throughout the non-metallic minerals processing industry. The greatest
variations in the design of baghouses arise from the methods of cleaning the
fabric filter and the choice of fabric and size of unit.
The actual extraction of dust is accomplished as shown in Figure 4-9.
The airstream enters the baghouse and is pulled up into fabric sleeves that
are clustered throughout the apparatus. External draw on the apparatus forces
the air to be pulled to the outside of these fabric sleeves which is a "clean
area." The dust remains trapped in the weave of the sleeve forming a cake
while the cleansed air is exhausted to the atmosphere. The dust is eventually
removed from the bag by one of several bag cleaning methods and is either re-
turned to the process or disposed of.
The reverse operation can just as easily be utilized; that is, dirty air
travels from the outside to the inside of the bag exiting through the top of
the bag, thus leaving the dirt accumulation on the outside of the sleeves.
This accumulation of dust forms a filter cake on the bags which must be
removed if there is to be sufficient flow through the system. Care must be
taken that the dust is removed and disposed of in such a manner that it does
not become reentrained and also that a residual filter cake remains to act as
a filtering mechanism in its own right.
Major methods of cleaning are shaking (rapping) and reversing airflow
by air jets or pulses. Shaking consists of manually or automatically shaking
the bag hangers or rapping the side of the baghouse to shake the dust free
into a receiving hopper below.
4-22
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HANGERS
CLEAN
AIR
DIRTY :
AIR
CLEAN
SIDE
AIR
BAG
COLLECTED
DUST
Figure 4.9 Typical baghouse operation,
4-23
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A less simple method is to use reverse airflow down the tubes at such a
rate that there is no net movement of air through the bag. This causes the
bag to.col lapse which results in the filter cake breaking-up and falling off
the bag.
A final method is reverse air pulsing where a perforated ring travels up
and down each bag or sleeve. Air jets in the ring force the bag to collapse,
then reopen breaking the filter cake apart. These two methods are shown in
Figure 4-10.
The frequency of cleaning can be continuous in which a section of bag-
house is removed from operation and cleaned before going on to another section
Alternatively, intermittent cleaning consisting of timed cycles of cleaning
and operation is used. Sensors can be installed that start the cleaning
cycle when some specified pressure drop across the system occurs because of
the buildup of the filter cake.
Materials available for bag construction are numerous. They are cotton,
Teflon glass, Orion, Nylon, Dacron, wool, Dynel, and others. Temperature and
other operating parameters must be taken into account in the selection of
fabric material, though most industry processes are at ambient conditions.
The most popular materials in terms of wear and performance are the synthetic
fabrics or cotton sateen.
Several other parameters are considered in the design of baghouses such
as frequency of cleaning, cloth resistances to corrosion and ore moisture.
The last major parameter considered is the air-to-cloth ratio or filter
ratio defined as the ratio of gas filtered in cubic feet per minute to the
area of the filtering media in square feet or ft3/min which reduces to feet
(or meters) per minute. Too high a ratio results in possible blinding or
4-24
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TUBE
COLLECTING
DUST
REVERSE
AIR ON
ONLY
WALLS COLLAPSE TOGETHER-
PREVENT DUST FROM FALLING
PRESSURE JET
AND REVERSE
AIR ON
SLUG OF AIR OPENS TUBEr
ALLOWS DUST TO FALL FREELY
Figure 4.10 Baghouse cleaning methods.
21+
4-25
-------
clogging of the bags and a resultant decrease in collection efficiency and
increase in bag material wear. The range of values for this parameter are
2.0 to 2.5:1, although some manufacturers will design some baghouses for oper-
ation of 4.5:1 up to 6:1 for lower costs, and lower efficiencies.25' 26
4.1.2.2.2 Wet Capture Devices
The principle of collection in wet capture devices involves contacting
dust particles with liquid droplets in some way and then having the wetted
and unwetted particles impinge upon a collecting surface where they can be
flushed away with water. The method of contacting the dust has many varia-
tions depending on the equipment manufacturer. The major types of wet col-
lectors are cyclone, mechanical, mechanical-centrifugal, and Venturi scrubbers,
These devices are more efficient than inertia! separators. Wet capture
devices can also handle high temperature gases or mist-containing gases.
Costs and efficiencies also vary with equipment selection and operating cond-
itions. Efficiencies are higher at lower particle size ranges than with dry
cyclones.
4.1.2.2.2.1 Cyclone Scrubbers
As with dry cyclones, wet cyclones impart a centrifugal force to the
incoming gas stream causing it to increase in velocity. The principal
difference here is that atomized liquids are introduced to contact and carry
away dust particles. The dust impinges upon the collector walls with clean
air remaining in the central area of the device. Efficiencies in this type
of equipment average in the vicinity of 98.2 percent.
4.1.2.2.2.2 Mechanical Scrubbers
These devices have a water spray created by a rotating disc or drum
contacting the dust particles. Extreme turbulence is created which insures
4-26
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this required contact. Efficiencies are about the same 35 cyclone wet scrub-
bers.
Mechanical centrifugal capture devices with water sprays are similar to
their dry counterparts with the exception that a water spray is located at
the gas inlet so that the particulate matter is moistened before it reaches
the blades. The water droplets containing particulate are impinged on the
blades while the clean air is exhausted as is depicted in Figure 4-11. In
this case, the spray not only keeps the blades wet so that dust will impinge
upon them, but it also serves as a medium to carry away particles.
Some types of scrubbers use high pressure-sprays, consuming more energy
and water, but have higher efficiencies than other wet capture devices.
Venturi scrubbers rely on an impaction mechanism and extreme turbulence
for dust collection. Gas velocities in the throat of the Venturi tube are
4,572 to 6,096 meters (15,000 to 20,000 feet) per minute. It is at this point
that low pressure water sprays are placed. The extreme turbulence causes
excellent contact of water and particulate. The wetted particles travel
through the Venturi tube to a cyclone spray collector. Efficiencies are very
high, averaging 99.9 percent.27 These high efficiencies are also evidenced
in the low particle size ranges collected ( <1 ym). This design is, indeed,
best suited to applications involving removal of 0.5 to 5 micron sizes.
The construction is similar to a Venturi meter with 25° converging and
7° diverging sections. This results in a 4:1 area reduction between the
inlet and throat.
4.1.3 Combination Systems
Wet dust suppression and dry collection techniques are often used in
combination to control particulate emissions from crushing plant facilities.
4-27
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VANES
CLEAN
EXHAUST
WATER SPRAY
DIRT
LADEN
AIR
Figure 4.11 Mechanical, centrifugal scrubber.
4-28
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As illustrated in Figure 4.12, wet dust suppression techniques are generally
used to prevent emissions at the primary crushing stage and at subsequent
screens, transfer points and crusher inlets. Dry collection is generally
used to control emissions at the discharge of the secondary and tertiary
crushers where new dry surfaces and fine particulates are formed. In addition
to controlling emissions, dry collection results in the removal of a large
portion of the fine particulates generated with the resultant effect of
making subsequent dust suppression applications more effective with a minimum
of added moisture. Depending on the product specifications, dry collection
may also be necessary at the finishing screens.
4.1.4 Control of Portable Plants
Dust control at portable crushing plants is considered by some industry
spokesmen to be difficult since utilities such as electricity and water may
be limited, and the amount of equipment that can be transported from location
to location is limited. The successful application of a wet dust suppression
system on a portable plant has, however, been reported.27 Furthermore, trailer
mounted portable baghouse units are presently commercially available and have
been utilized to control emissions from portable asphalt concrete batch plants.
Portable plant equipment manufacturers have indicated, unofficially, that
this control option is indeed feasible and that the required hoods, en-
closures and ductwork could be integrated into the design of the portable
plant components.
4.2 FACTORS AFFECTING THE PERFORMANCE OF CONTROL METHODS.
4.2.1 Dust Suppression
The effectiveness of wet suppression is dependent on the amount of
moisture added to the process flow. There are a number of factors which
4-29
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TRUCK DUMP
AND FEEDER
BAG
COLLECTOR
PRIMARY
CRUSHER
BIN AND TRUCK
LOADING STATION
SUPPRESSION
TERTIARY
CRUSHER
Figure 4.12 Typical combination dust control systems.
4-30
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may affect the performance ot a wet dust suppression system. These include
the wetting agent used, the method of application, characteristics of the
material, and the type and size of the process equipment serviced. The
number, type and configuration of spray nozzles at an application point,
as well as the speed at which a material stream moves past an appli-
cation point, may affect both the efficiency and uniformity of wetting.
In addition, meteorological factors, such as wind, ambient temperature
and humidity, which affect the evaporation rate of added moisture, may
also adversely affect the overall performance of a dust suppression
system. Where the material processed contains a high percentage of
fines, such as the product from a hammermill, dust suppression may be
totally inadequate because of the enormous surface areas to be treated.
Dust suppression may offer a viable control alternative to dry collec-
tion at process facilities if sufficient moisture is added to the material.
Generally, wet dust suppression is only possible with crushing operations
(crushers, conveyor transfer points, and screens) because a coarser material
is handled and plugging problems will not likely occur. In addition,
wet suppression may not be possible in freezing weather or arid region?.
Also, some industries (e.g., potash, talc, rock salt) prefer not to handle
material with high moisure (even in crushing operations).
4.2.2 Dry Collection
For dry collection systems, factors affecting both capture efficiency
and collection efficiency are important. Wind blowing through hood
openings can significantly reduce the effectiveness of a local exhaust
system. This can be appreciated when one considers that an indraft
velocity of 61 meters/min (200 fpm) is equivalent to less than 3.7 km/hr
4-3,1
-------
(2.3 mph). Consequently, the process equipment should be completely
enclosed or the hood openings minimized.
installations located in areas of high precipitation have chosen to
house process equipment in buildings or structures to increase their
operating hours. An added effect of this is to reduce the impact that high
winds may have on a local exhaust system which is not properly enclosed. Exc
for crushed and broken stone plants and sand and gravel plants, much of
the processing in the industries investigated in this study occurs in
buildings which enclose the equipment.
An exhaust system must be properly maintained and balanced if it is
to remain effective'. Good practice dictates that systems be periodically
inspected and capture and conveying velocities checked against design
specifications to assure that the system is indeed functioning properly.
The primary causes for systems becoming unbalanced are the presence of
leaks resulting from wear due to abrasion or corrosion, and the settling
of dust in poorly designed duct runs which effectively reduces the cross
sectional area of the duct and increases pressure drop.
4.2.3 Combined Suppression and Collection Systems
The factors affecting the performance of combination systems are the
same as those encountered where dust suppression or dry collection systems
are used alone.
4.3. PERFORMANCE OF PARTICULATE EMISSION CONTROL TECHNIQUES
4.3.1 Dry Collection Techniques
4.3.1.1 Particulate Emission Data
Particulate emission measurements were conducted by EPA on 16 baghouse
collectors used to control emissions generated at crushing, screening, and
4-32
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conveying (transfer points) operations at five crushed stone installations,
one kaolin plant, one fuller's earth installation and on one baghouse collec-
tor used to control emissions generated at grinding, classifying, and fine
product loading operations at a feldspar installation. Table 4.2 briefly
summarizes the process operations controlled by each baghouse tested, along
with specifications for each baghouse. The results of these measurements are
summarized in Figure 4.13. Complete test data summaries, for both mass
particulate measurements and visible emission observations, and a description
of each process facility tested are contained in Appendix C.
Of the eight plants tested, three processed limestone rock (A, B, and C),
two processed traprock (D and E), one processed feldspar (G), one processed
kaolin (L), and one processed fuller's earth (M). Four of the five crushed
stone plants were commercial crushed stone operations producing a variety of
end products including dense-graded road base stone, bituminous aggregatesj
concrete aggregates and non-specific construction aggregates. In addition,
plant B produced about 60 ton/hr of agstone. Facilities Al through A4 consist
of process operations producing raw material for the manufacture of portland
cement. Facilities Al and Bl are both impact crushers used for the primary
crushing of run-of-quarry limestone rock. Facility A3 is somewhat unique in
that it consists of a single conveyor transfer point at the tail of an over-
land conveyor. As indicated in Table 4.2, the remaining facilities tested
consisted of multiple secondary and tertiary crushing and screening operations,
adjunct conveyor transfer points, and grinding operations. These include one
primary jaw crusher, three secondary cone crushers, two hammer mills, eight
tertiary cone crushers,, nineteen screens, thirteen product bins, and over
4-33
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TABLE 4.2 BAGHOUSE UNITS TESTED BY EPA
Fac- Rock type
ility processed
Al
A2
A3
A4
Bl
B2
Cl
C2
Dl
D2
El
E2
Ml
M2
Gl
LI
L2
Limestone
Limestone
Limestone
Limestone
Limestone
Limestone
Limestone
Limestone
Traprock
Traprock
Traprock
Traprock
Fuller's earth
Fuller's earth
Feldspar
Kaolin
Kaol in
Baghouse specifications
Type
Jet pulse
Jet pulse
Jet pulse
Jet pulse
Shaker
Shaker
Shaker
Shaker
Shaker
Shaker
Jet pulse
Jet Pulse
Reverse air
Reverse air
Reverse air
Unknown
Unknown
Fil tering
ratio
5.3 to 1
7 to 1
7 to 1
5.2 to 1
3.1 to 1
2.1 to 1
2.3 to 1
2.0 to 1
2.8 to 1
2.8 to 1
5.2 to 1
7.5 to 1
6.0 to 1
5.2 to 1
3.0 to 1
Unknown
Unknown
Capacity
scms
12.5
7.5
1.1
5.0
2.7
8.6
3.5
3.1
15.0
12.3
7.0
10.0
0.9
1.6
1 .9
6.6
3.3
scfm
(26,472)
(15,811)
(2,346)
(10,532)
(5.784)
(18,197)
(7,473)
(6,543)
(31,863)
(25,960)
(14,748)
(21,122)
(1,800)
(3,300)
(3,960)
(14,040)
(6,960)
Process operations controlled
Primary impact crusher
Primary screen
Conveyor transfer point
Secondary cone crusher, screen
Primary impact crusher
Scalping screen, secondary cone crusher, two finishing
screens, hammer mill, five storage bins, six conveyor
transfer points
Primary jaw crusher, scalping screen, hammer mill
Two finishing screens, two conveyor transfer points
One scalping and two sizing screens, secondary cone
crusher, two tertiary cone crushers, several conveyor
transfer points
Finishing screen, several conveyor transfer points
Two sizing screens, four tertiary cone crushers;
several conveyor transfer points
Five finishing screens, eight storage bins
Raymond and fluid energy mills, conveyor transfer
points, vibrating screens
Pebble mill, bucket elevator, two conveyor transfer
points, fine product loading
Raymond impact mill
Rol ler mi 1 1
-------
0.02
0.015
o
0
H-
U
O U
OO T3
U~i I-
*-< (13
H "O
UJ C
uj 5 0.01
h— l/l
O X)
1— l-
CŁ 0)
CC Q.
CL
c
ID
t.
.01
0.005
0
Facility
Rock Type
KEY
to
I+-H AVERAGE
t1
« EPA TEST METHOD
O OTHER TEST METHOD
fl
b
1
iTj i
F"!
i | h — »
• I '
' i
1 1 i
i ' '
i C^C)
l
(D i
uCTli Cl '
TrT ^
" ,!dn '
? ^ ' w ,
Al A2 A3 A4 Bl B2
L L L L L L
f\
ft
I
« *
P 1 1
II 1
Ci Ci
I ^
1 | II
" II to
c | |
i i
i i
w 'd fi "
A |i
•")•! [ |a
Wj<^/ | | ||
-------
seventeen conveyor transfer points, one pebble mill, two roller mills, one
fluid energy mill, one impact mill, one bucket elevator, and a fine product
loading system.
A minimum of three test runs, using EPA Method 5 or 17, were conducted
at each process operation tested. (For this industry, both EPA Method 5
and 17 are acceptable particulate sampling methods, see Appendix D.) Sampling
was performed only during periods of normal operation and was stopped and
restarted to allow for intermittent process shutdowns and upsets (feed to
the process). Where the process weight rate was undeterminable at a specific
process operation, as in most instances, the process weight through the
primary crushing stage was monitored to assure that the plant was operating
at or near normal capacity. Moisture determinations on the material processed
were also performed at each plant tested (except for plants A, G, L and M)
to permit an assessment of whether control was effected primarily by the dust
collection system or by excessive moisture inherent in the material processed.
The tests were considered valid if the material moisture was less than two
percent.
The baghouses tested included jet pulse, reverse air, and mechanical
shaker type units. The shaker type and reverse air type fabric filters
used cotton sateen bags and were operated at about 2:1 to 3:1 air-to-
cloth ratios. The jet pulse units tested were fitted with wool or
synthetic fiber felted bags. Air-to-cloth ratios ranged from about
5:1 to 7.5:1.
A study29 performed by the Industrial Gas Cleaning Institute
(IGCI) under contract to EPA reported air-to-cloth ratios necessary to
achieve 0.05 g/dscm (0.02 gr/dscf) for the various industry segments
4-3B
-------
based upon the experience of their member companies. Table 4.3 presents
this information. These ratios are based upon the following premises:
1. Air from a dry crushing or grinding operation at or near ambient
temperature.
2. An inlet particulate content of 10 grains per standard cubic foot
for a volume of air equivalent to that required for a face velocity
of 200 ft/min at crusher openings.
3. A particle size average of 20 microns and a range from 0.5
to 100 microns.
4. No insulation or heating required.
The IGCI report states that the segments considered the most troublesome
are those with the lowest air-to-cloth ratio. The lower ratios employed
for some segments are premised upon such particulate properties as a high
abrasiveness or a tendency to "blind" the filtering medium. The study
further states that no differentiation in the air-to-cloth ratio is required
for the source of emission be it crushing or grinding operation. An
exception would be a micromill source emitting an average particle size
smaller than that cited (i.e. 20 microns). For such a source, a lower
air-to-cloth ratio would be needed than that indicated in Table 4.3.
The industry segment with the lowest air-to-cloth ratio listed in
Table 4.3 is feldspar. EPA conducted tests for particulate emissions at
a feldspar plant on a baghouse controlling emissions from a pebble mill
system. The results of these tests indicate particulate emissions below
0.023 g/dscm (0.01 gr/dscf). The baghouse had a design air-to-cloth
ratio of 3.03.
4-37
-------
Table 4.3. AIR-TO-CLOTH RATIOS FOR FABRIC
FILTERS USED FOR EXHAUST EMISSION CONTROL
Air-to-cloth2ratioa
Industrial segment acfm/ft
Sand and gravel 7.
Clay 6.
Gypsum 6.
Lightweight aggregate 7.5
Perlite
Vermiculite
Pumice 4.5
Feldspar 4.
Borate 5.
Talc and Soapstone 5.
Barite 5.
Diatomite 6.
Potash 6.
Rock Salt 4.5
Fluorspar 6.
Mica 6.
Kyanite 4.5
Sodium Compounds 6.
Natural asphalt and related bitumens N.R.*3
Crushed and broken stone 7]
Ratio is based on operating surface required to obtain a particulate
concentration of 0.02 grain per standard cubic foot in the outlet
stream from the filter. In all cases, the filter is a pulse-jet
type operating at 6 in. W.G. differential pressure. The filtering
medium is felted polypropylene or polyester.
No recommendation for this segment.
4-38
-------
In addition, the IGCI report listed test results (using EPA sampling
Method 5) for two fluid energy mills processing clay (fuller's earth). In
both cases, the particulate emissions were controlled by a fabric filter
and were below 0.023 g/dscm (0.01 gr/dscf). The average particle size of
the inlet stream was reportedly below 10 microns in both cases. EPA con-
ducted tests for particulate emissions from a roller mill and a fluid energy
mill, both used to grind fuller's earth clay. In both cases particulate
emissions were controlled by baghouses. Emissions from the baghouse control-
ling the roller mill were less than 0.005 g/dscm (0.002 gr/dscf) and those
from the fluid energy mill baghouse were less than 0.015 g/dscm (0.006 gr/dscf)
Tests were also conducted at two talc plants and a gypsum plant on
baghouses controlling particulate emissions from various process sources.
Emissions from these baghouses were greater than 0.05 g/dscm (0.02 gr/dscf).
The higher emission levels are suspected to have been caused by the presence
of torn bags since there were excessive visible emissions either continuously
or frequently. Tests conducted at a kaolin plant on an impact mill and a
roller mill resulted in measured emission rates of 0.037 and 0.016 g/dscm
(0.016 and 0.007 gr/dscf) respectively, for the two process operations.
As previously indicated, test results are presented on only three of
the 20 industries being covered. These are crushed stone (limestone and
trapock), feldspar, and clay (fuller's earth, kaolin). The crushed stone
data for feldspar, kaolin, and fuller's earth clay are for grinding systems.
All the facilities tested are controlled by fabric filter collectors. Since
the performance of fabric filter collectors is relatively unaffected by the
size distribution of participate, the emission levels from properly designed
baghouses should be nearly the same over the wide variety of non-metallic
4-39
-------
minerals being covered.30'31 Furthermore, the ICGI report stated that
there is no difference in performance of a baghouse whether it is installed
on a crushing or grinding operation for a particular industry. The difference
in design (air-to-cloth-ration) of a baghouse for the various industries
are premised upon such particulate properties as high abrasiveness or a
tendency to "blind the filtering medium." The IGCI report also states
that the worst situation would be a source emitting an average particle
size smaller than 20 microns. The clay grinding mills (fluid energy mill,
see Section 3.2.2.3.4) tested are the type of grinders generally used when
an ultrafine product is required. Therefore, the data presented on the clay
grinding mills, which have an average particle size of 6 microns or less,
would represent the levels achievable under worst conditions.
As discussed earlier, the average emission concentration for the differ-
ent process facilities using properly operated baghouses at the various non-
metallic industries shown in Figure 4-13 was 0.011 g/dscm (0.005 gr/dscf).
The average outlet concentration at any of these facilities never reached
0.046 g/dscm (0.02 gr/dscf). In conclusion, it is felt that the data pre-
sented here are representative of the levels that can be achieved by a properl
designed baghouse in each of the 20 industries.
4.3.1.2 Visible Emissions Data
Visible emission observations were also made during the emission tests
described above. The exhaust from each of the fabric filters tested was
observed in accordance with EPA Method 9 procedures. Visible emis-
sions observed from the fabric filters at Plant A, C, D, E, G
and M were essentially zero. The highest 6-minute average recorded at Plant
B was 1 percent opacity. Plant L, a kaolin plant, exhibited continuous
4-40
-------
visible emissions of less than 5 percent opacity. This was considered to be
steam, since only the first of three tests (which was conducted in the morning)
had visible emissions. As the temperature of the ambient air rose, the visible
emissions dissipated.
Observations for visible emissions were also made at hoods and enclosures
to record the presence and opacity of emissions escaping capture. The results
of these measurements are summarized in Table 4.4. Complete data summaries are
contained in Appendix C. In most instances, essentially no visible emissions
were observed at adequately hooded or enclosed process facilities.
Of the 13 crushers for which visible emission measurements are reported,
10 were cone crushers handling either limestone, traprock, feldspar, or talc.
The other three crushers were an impact crusher handling limestone and jaw
crushers handling feldspar and talc. Except for one jaw crusher and one cone
crusher, no visible emissions were observed from crushers for at least 97 per-
cent of the time. The one cone crusher (facility B) had visible emissions
for 10 percent of the time, but this crusher was identical to two other cone
crushers tested at the same facility which had no visible emissions for 100
percent of the time. The jaw crusher (facility J) had visible emissions for
28 percent of the time but the percentage would have been lower if a cover
plate had not been removed during part of the observation period.
In addition, the tests performed at facility B, which include the cone
crusher exhibiting visible emissions for 10 percent of the time were carried
out while the facility was experiencing dry climatic conditions and problems
with their water suppression system's pump. As with facility J, a cover plate
at the primary crusher had been removed. Lastly, EPA personnel at the test
felt that, in general, the capture system was not designed as well as other
4-41
-------
TABLE 4.4. SUMMARY OF VISIBLE EMISSIONS MEASUREMENTS FROM FUGITIVE SOURCES
AT NON-METALLIC MINERALS PLANTS
•Ł:>
ro
_ , Accumulated
Plant/Rock type processed ^e ° Process facility observation time
test (minutes)
A
B
D
F
Crushed limestone 7/9/75 Baghouse discharge to conveyor
Primary impact crusher discharge
Conveyor transfer point
Crushed limestone 7/1/75 Scalping screen
Surge bin
Secondary cone crusher No. 1
Secondary cone crusher No. 2
Secondary cone crusher No. 3
Hammer mil 1
3-deck finishing screen (L)
3-deck finishing screen (R)
6/30/75 Two 3-deck finishing screens
Crushed stone 7/8/75 No. 1 tertiary gyrasphere
cone crusher
No. 2 tertiary gyrasphere
cone crusher
Secondary standard cone crusher
Scalping screen
Secondary (2-deck) sizing screen
Secondary (3-deck) sizing screen
Traprock 8/26/76 Two tertiary crushers
Four processing screens
Conveyor transfer points
240
240
166
287
287
231
231
231
287
107
107
120
170
170
170
210
210
210
65
180
179
Accumulated
emission time
(minutes)
0
4
3
45
3
23
0
0
0
4
0
86
0
0
0
0
0
0
0
0
0
Percent of time
with visible
emissions
0
1
2
15
1
10
0
0
0
4
0
72
0
0
0
0
0
0
0
0
0
(continued)
-------
TABLE 4.4 (continued)
-Ps
I
GO
Date of Accumulated
Plant/Rock type processed Process facility observation time
test ' (minutes)
G Feldspar
H Gypsum
I Mica
J Talc
N Kaolin
9/27/76 Conveyor transfer point No. 1
Conveyor transfer point No. 2
Primary crusher
Secondary crusher
Conveyor transfer point No. 4
Ball mill (feed end)
Ball mill (discharge end)
Indoor transfer point No. 1
Indoor transfer point No. 2
Indoor bucket elevator
(PUCK loading
Rail car loading
10/27/76 Hammer mill
9/30/76 Bagging operation
10/21/76 Vertical mill
Primary crusher
Secondary crusher
Bagger
Pebble mill
12/7/78 Rail car loading
Test 1
Test 2
Test 3
80
87
60
60
84
60
60
60
60
6G
ij
32
298
60
90
90
150
150
90
144
99
154
Accumulated
emission time
(mi nutes)
0
0
1
0
0
0
0
0
0
0
U
5
2
0
0
20
4
13
6
17
2
9
Percent of time
with visible
emi ssions
0
0
2
0
0
0
0
0
0
0
U
15
1
0
0
22
3
9
7
12
2
6
-------
systems used in the industry. The combination of these factors account for the
high readings of visible emissions at the cone crusher and screening operations,
Visible emissions were observed at six grinding mills. All the mills
except the pebble mill exhibited no visible emissions 99 percent of the time.
(The vertical mill is a closed system and, therefore, would not have a fugitive
discharge of dust except through leaks in the system.) Visible emissions were
observed from the other ball mills for 0 percent of the time and for the pebble
mill for 7 percent of the time. Three visible emissions tests were conducted
at the rail car bulk loading operation of a kaolin plant. For two tests during
which rectangular hatch rail cars were loaded visible emissions were observed
for 2 and 6 percent of the time. Visible emissions were observed for 15 percent
of the time during loading of a "rake-back" rail car. The primary source of
emissions was the topping of each compartment and the subsequent repositioning
of the feed hose in the next compartment.
Opacity measurements are also reported for eight screens, seven conveyor
transfer points, one bucket elevator, one product bin, and two baggers. Except
for two screens at facility B, visible emissions were observed from these process
facilities for periods ranging from 0 percent to 9 percent of the time. The
remaining screen had visible emissions for 15 and 72 percent of the time.
Both the screens were located at facility B. The reasons for the high readings
were given in the discussion of the problems at facility B, above. The main,dust
source at one of the screens was mainly at the motor powering the screens.
4.3.2 Met Dust Suppression Techniques
Due to the unconfined nature of emissions from facilities controlled by
wet suppression technique, the quantitative measurement of mass particulate
emissions is not possible. Thus, no mass emission data are available which
4-44
-------
permit a quantitative comparison of the control capabilities of wet dust
suppression versus dry collection techniques. Visible emissions observations
were conducted, however, at a traprock installation using wet dust suppression
techniques to control particulate emissions generated at plant process facilities
(see facility F, Appendix C). During the periods of observation, no visible
emissions were observed at two crushers, four screens, and one conveyor transfer
point. The two crushers were observed simultaneously for a period of 65 minutes.
The four screens were observed simultaneously for 3 hours. The conveyor transfer
point was observed for 3 hours.
Visible emission observations were also conducted at a feldspar crushing
installation which had a wet dust suppression system to control particulate
emissions generated (see facility G, Appendix C) by crushers, screens, and
conveyor transfer points. During the observations the suppression system was
used only intermittently, presumably because the ore had sufficient surface
moisture from rains the previous day. During the periods of observation,
essentially no visible emissions were observed. Surface moisture contents of
the ore were 1.6 to 1.8 percent at the primary crusher discharge; 1.4 to 1.5
percent at the secondary crusher feed; and 1.0 percent at the secondary crusher
discharge conveyor.
4-45
-------
REFERENCES FOR CHAPTER 4
1. "Rock Products Reference File - Dust Suppression," Rock Products,
May 1972, p. 156.
2. Weant, G.E., "Characterization of Particulate Emissions from the Stone-
Processing Industry," prepared by Research Triangle Institute for the
United States Environmental Protection Agency, Contact No. 68-02-0607-10
May 1975, p. 64.
3. Johnson-March Corporation, Product Literature on Chem-Jet Dust
Suppression System, 1071.
4. Courtesy of Johnson-March Corporation.
5. Reference 4.
6. Hankin, M., "Is Dust the Stone Industry's Next Major Problem," Rock
Products, April 1967, p. 84.
7. "Air Pollution Control at Crushed Stone Operations," National Crushed
Stone Association, February 1976, page V-4.
8. Reference 6, p. 114.
9. Reference 7, page V-5.
10. Anderson, D. M., "Dust Control Design by the Air Induction Technique,"
Industrial Medicine and Surgery, February 1964, p. 3.
11. Telephone conversation between Mr. Alfred Vervaert, EPA, and Mr. Joe
McCorkel, Aggregates Equipment Incorporated, January 28, 1975.
12. Reference 11.
13. Reference 11.
14. American Conference of Governmental Industrial Hygienists, "Industrial
Ventilation, A Manual of Recommended Practice", llth Edition, 1970,
p. 5-33.
15. Reference 6, p. 2
16. Reference 14, p. 5-32.
17. Reference 14, p. 5-33.
18. Reference 14, p. 5-31.
19. Reference 14, p. 5-28.
4-46
-------
20. "Control Techniques for Particulate Air Pollutants," U.S. Environmental
Protection Agency, Publication No. AP-51 , January 1969, pp. 46-47.
21. "Source Testing Report - Kentucky Stone Company, Russellville, Kentucky,"
prepared by Engineering - Science, Incorporated, EPA Report No. 75-STN-3.
22. "Emission Study at a Feldspar Crushing and Grinding Facility," prepared
by Clayton Environmental Consultants, Incorporated, EPA Report
Number 76-NMM-l.
23. Reference 20.
24. "Air Pollution Engineering Manual," Second Edition, U.S. Environmental
Protection Agency, Publication AP-40. p. 128, May 1973.
25. Reference 24, p. 116.
26. Reference 24, p. 117.
27- Reference 25, p. 104.
28. Greesaman, J. "Stone Producer Wins Neighbors' Acceptance," Roads and
Streets, July 1970.
29. Emission Characteristics of the Non-metallic Minerals Industry, Industrial
Gas Cleaning Institute, EPA Contract No. 68-02-1473, Task No. 25, July
1977.
30. Control Techniques for Particulate Air Pollutants. National Air Pollution
Control Administration, Public Health Service, U.S. Department of Health,
Education, and Welfare. Washington, D.C. NAPCA Publication No. AP-51.
January 1969.
31. Billings, C. E. and J. Wilder, Handbook of Fabric Filter Technology
In: Fabric Filter System Study (Volume I). GCA Corporation, GCA/
Technology Division. Bedford, Massachusetts, Contract No. CPA 22-69-
38. December 1970.
4-47
-------
5. MODIFICATION AND RECONSTRUCTION
For the non-metallic minerals processing industry, the affected facility
is defined as the entire stationary or portable processing plant including
crushers, grinding mills, screens, bucket elevators, conveyor transfer points,
bagging operations, storage bins and fine product truck and railcar loading
stations. Excluded are drilling, blasting, loading at the mine, hauling,
stockpiling, conveying (other than at transfer points), windblown dust from
stockpiles, roads and plant yards, calciners, and dryers.
In accordance with Section 111 of the Clean Air Act, standards of
performance shall be established for new emission sources, or "affected
facilities," within a stationary source category. The standards, upon
promulgation, apply to affected facilities for which a construction or mod-
ification commenced after proposal of the standards.
5.1 APPLICABILITY TO NON-METALLIC MINERALS PROCESSING PLANTS
5.1.1 Modification
As indicated in Chapters 3 and 4, a non-metallic minerals processing
plant is composed of any combination of crushers, grinders, and mate-
rial transfer systems and a variety of control equipment. For an existing
facility to become an affected facility, the sum total of the emissions from
all included process operations must increase. A total increase in emissions
from one or more individual process operations may be compensated for by
an equal or greater total decrease in emissions from the remaining process
operations.
5-1
-------
The following physical or operational changes are not considered modi-
fications to existing non-metallic minerals processing facilities, irrespec-
tive of any change in the emission rate:
a. Changes determined to be routine maintenance, repair or replace-
ment. For non-metallic minerals processing plants, this includes
the replacement or refurbishing of equipment elements subject to
high abrasion and impact such as crushing surfaces, screening
surfaces and conveyor belts; and replacement of equipment with
no increase in capacity.
Under the reconstruction provisions applicable to all standards
of performance, an existing facility would become subject to the
standards if its components are replaced to such an extent that
the fixed cost of the new components exceeds 50 percent of the
fixed capital cost that would be required to construct a compa-
rable entirely new facility.
b. An increase in the production rate if that increase can be accomp-
lished without a capital expenditure exceeding the existing
facility's IRS annual asset guideline repair allowance of 6.5
percent per year.
c. An increase in the hours of operation.
d. Use of an alternative raw material if the existing facility was
designed to accommmodate such material. Since process equipment
(crushers, screens, conveyors, etc.) are designed to accommodate
a variety of rock types, any change in raw material feed would
probably not be considered a modification.
5-2
-------
e. The addition or use of any air pollution control system except
when a system is removed or replaced with a system considered to
be less effective.
f. The relocation or change in ownership of an existing facility.
Under this exemption, the relocation of a portable plant would
not be considered a modification.
The impact of the modification provision on existing non-metallic
minerals processing facilities should be very slight. Except as noted above,
no condition is foreseen which would deem an existing non-metallic minerals
processing facility modified.
5.1.2 Reconstruction
The reconstruction provision is applicable only where an existing facility
is so extensively rebuilt that it is virtually identical to an entirely newly
constructed facility. This would most likely require the construction of an
entire new process stream (.i.e., a new plant). For this reason, the impact
of the reconstruction provision would be negligible for the non-metallic
minerals industry.
5.1.3 Expansion of Existing Facilities
When expansions at existing plants take place the newly added equipment
(if part of one of the included process operations) would be considered in
the total emissions produced by the plant. Crushing operations at non-metallic
minerals plants usually operate below 100 percent capacity and are usually
capable of handling increased throughput without additional equipment. Such
an increase in production as stated in Section 5.1.1, would not be considered
a modification. However, in order to expand the grinding capacity of the
plant, a complete new grinding line would probably be added and would
5-3
-------
constitute modification. Emissions from this grinding line would be included
in the total emissions summation. In order for the plant not to become subject
to the standards via modification, it would have to demonstrate that there
would be no emission increase as a result of the expansion.
5-4
-------
6. EMISSION CONTROL SYSTEMS
The alternative control systems that are considered the best combination
of the control techniques previously discussed are presented in this chapter.
The analysis of environmental effects in Chapter 7 and of economic impacts in
Chapter 8 will examine the impacts associated with the alternative emission
control systems.
As discussed in Chapter 4, both dry collection and wet suppression systems
are considered as viable control alternatives. Unfortunately, the emissions
from a wet suppression system are not amenable to measurement and therefore
cannot be quantified. In addition, wet suppression systems cannot be used
in all cases throughout the industry and therefore cannot be considered a can-
didate for best technology. Thus, major emphasis of developing the environ-
mental and economic impacts for the non-metallic mineral industry will be placed
on dry collection systems and wet suppression systems will be discussed only
briefly. Since the dry collection systems are more costly and require more
energy (for fans), the impacts on the industry will be overstated as compared
to an analysis based on industry use of both dry and wet collection systems.
The model plants which will be analyzed for estimating cost impact and
environmental impact are shown in Table 6.1. Two basic models of non-metallic
mineral plants were developed. The first model plant consists of crushing
operations only, and includes: primary, secondary, and tertiary crushers,
three or four screening operations, five to 10 transfer points, and the storage
bin loading operation. The second model plant includes both a crushing
6-1
-------
Table 6.1 Model Plants for Estimating Environmental
and Economic Impact
Plant
Size
[Mg/hr (TPH)]
9.1 (10)
9.1 (10)
22.7(25)
22.7(25)
68.0(75)
68.0(75)
Model
Plant
1
2
1
2
2
2
Gas Volume Plant
to-Baghouses Size
[nT/s (cfm)] [Mg/hr (TPH)]
4.8 (10,200)
4.8 (10,200)
1.9 (4,000)
5.4 (11,500)
5.4 (11,500)
2.2 (4,700)
8.4 (17,800)
8.4 (17,800)
3.2 ( 6,700)
136 (150)
136 (150)
272 (300)
272 (300)
544 (600)
544 (600)
Model
Plant
1
2
1
2
1
2
Gas Volume
to,,Baghouses
[rrr/s (cftn)l
11.8 (25,000)
11.8 (25,000)
5.3 (11,300)
18.9 (40,000)
3.8 ( 8,000)
18.9 (40,000)
3.8 ( 8,000)
10.4 (22,600)
4.2 ( 9,000)
15.1 (32,000)
14.6 (31,000)
4.2 ( 9,000)
15.1 (32,000)
14.6 (31,000)
21.2 (45,200)
Notes:
"Model 1 - crusher (primary, secondary, and tertiary),
screens (3 or 4), transfer points (5 to 10),
and storage bin loading operation.
'Model 2 - crusher (primary, secondary, and tertiary),
grinder, screens (3 or 4), transfer points
(5 to 10), storage bin loading operation,
and bagging machine.
'In all cases, baghouses are used as the control device(s)
6-2
-------
operation and a grinding operation—the latter consisting of a grinding mill,
classifier or screen, two additional transfer points and a bagging machine.
Both model plants use baghouses as the control device(s).
The model plants for analysis consist of 9, 23, 68, 136, 272, and 544
megagrams per hour (Mg/hr) (10, 25, 75, 150, 300 and 600 tons per hour)
stationary plants and a 181 Mg/hr (200 TPH) portable crushing plant.
The process equipment and associated energy requirements and air volumes
used in defining the model plants are contained in Table 6.2. The parameters
listed are used as the basis for the energy usage calculations presented in
Section 7 and the cost and economic impact analysis in Section 8. Parameters
for the 272 and 544 Mg/hr (300 and 600 ton/hr) model plants were derived from
flow diagrams presented in the industrial literature. Energy requirements and
gas volumes for the smaller model plants were calculated from equipment spec-
ifications and flow correlations.
The two model plants and six plant sizes are not applicable to each non-
metallic mineral industry. The model plant used for each industry, the
typical range of plant sizes found in the industry, the typical plant size
and the plant sizes which will be used in determining the economic and environ-
mental impacts for each industry are listed in Table 6.3. All the industries
employ crushing and grinding operations (Model Plant 2) except crushed and
broken stone, sand and gravel, perlite, vermiculite and rock salt. Generally,
the size of non-metallic minerals plants is less than 136 Mg/hr (150 TPH)
except for plants in the crushed stone, sand and gravel, and potash industries.
6-3
-------
Table 6.2 List
Air
10 TPH
of Process Equipment Including Energy Requirements and
Volume Requirements Used in Determining Model Plants
25 TPH 75 TPH
Item
Primary
Crusher
Primary
Screen
Secondary
Crusher
Secondary
Screen
Tertiary
Crusher
Tertiary
Screen
Feeder
Storage Bin
Conveyors
Transfer
Points
Grinder
System
Total -
Crushing
Plant
Only
(Model 1)
Total -
Crushing and
Grinding
(Model 2)
Size
10"x 21"
Jaw
3x4
2' cone
3x4
24"x 30"
Roll
3x4
(2)
18" (3)
18" (5)
6x8
Ball Mill
Energy
Requirement
HP
35
2
25
5
40
5
5
20
150
137
287
Gas Vol.
CFM
375
600
2000
600
1250
600
1000
3750
4000
10175
14175
Size
10"x 30"
Jaw
3x8
13 x 59
gyratory
3x8
24"x 30"
Roll
3x8
(2)
18" (3)
18" (5)
8x7
Ball Mill
HP
60
5
30
5
40
5
7.5
20
300
172.5
472.5
CFM
525
1200
1325
1200
1250
1200
1000
3750
4700
11450
16150
Size
15"x 38"
6 x 10
13 x 59
gyratory
6 x 10
10"x 39"
Hammermi 1 1
6 x 10
(2)
24" (1)
18" (2)
24" (1
18" (4)
10 x 12
Ball Mill
HP
75
15
70
15
200
15
7.5
7
13
800
417.5
1217.5
CFM
1000
3000
1325
3000
1350
3000
1000
1000
3000
6700
17675
24375
en
i
-------
150 TPH
300 TPH
600 TPH
Item
Size
HP
CFM
Size
CFM
Size
CFM
Primary
Crusher
Primary
Screen
Secondary
Crusher
Secondary
Screen
Tertiary
Crusher
Tertiary
Screen
Feeder
Storage Bin
Conveyors
Transfer
Points
Grinder
System
Total -
Crushing
Plant
Only
(Model 1)
Total -
Crushing and
Grinding
(Model 2)
27"c 42"
Jaw
6 x 12
4' cone
6 x 12
13"x 59"
Gyratory
6 x 12
(3)
30" (1)
24" (2)
24" (3)
30" (2)
10 x 12 (2)
Ball Mill
- 150
20
150
20
125
2°,
7.5
12
19.5
1600
524
2124
2500 : 35"x 46"
3600
3250
3600
1325
3600
1500
3000
2500
11300
25399
36699
Jaw
6 x 12
4 h cone
6 x 16
4' cone
4' cone
7 x 20
(5)
36" (2)
30" (3)
24" (3)
36" (3)
30" (4)
24" (7)
10 x 12 (4;
Ball Mill
200
20
175
20
150
150
30
10
29
48
13
3200
845
4045
3500
3600
3660
4800
3260
3260
7000
2500
4500
5000
7000
22600
48080
70680
50"x 60"
Jaw
6 x 12
5 % cone
5 35 cone
6 x 16
5 % cone
5 JJ cone
7 x 20
7 x 20
(5)
36" (3)
30" (4)
36" (3)
30" (7)
10 x 12 (8)
Ball Mill
300 4660
20
200
200
20
200
200
30
30
20
113
59
6400
1392
3600
6170
6170
4800
6170
6170
7000
7000
2500
9000
8750
45200
71990
7792 117190
CTl
CJ1
References: - Estimating Dust Control Costs for Crushed Stone Plants, Bureau of Mines Report, Rock Products, April, 1975.
- Mineral Processing Flowsheets, Denver Equipment Company, Second Edition.
- Cedarapids Reference Book, Iowa Manufacturing Company, Ninth Pocket Edition.
- Background Information for the Non-Metallic Minerals Industry, PEDCo Environmental Specialists, EPA
EPA Contract No. 68-02-1321 Task No. 44, August 31, 1976.
- Chemical Engineers Handbook, 3rd Edition, Perry,, Robert H. (editor), McGraw Hill.
- Pit and Quarry Handbook and Purchasing Guide, 63rd Edition, Pit and Quarry Publications, Incorporated, 1970.
- "Industrial Ventilation, A Manual of Recommended Practice, llth Edition, American Conference of Govern-
mental Industrial Hypienists, 1970.
- Smith Engineering works, Product Literature on Telsmith Equipment for Mines ... Quarries and Gravel Pits,
Bulletin 266 B.
-------
Table 6.3 Plant Sizes for the Various
Non-Metallic Minerals Industries
(Metric Units)
Industry
Crushed & Broken Stone
Sand & Gravel
Clay
Rock Salt
Gypsum
Sodium Compounds
Potash
Pumice
Natural Asphalt &
Related Bitumens
Talc
Boron
Barite
Fluorspar
Pyrites
Feldspar
Diatomite
Perlite
Vermiculite
Mica
Kyanite
Plant
Model
Used
1
1
2
1
2
2
2
2
2
2
2
2
2
2
2
2
1
1
2
2
Range
Mq/hr
-
14-2177
4-136
-753
-
-204
54-408
5-30
-
5-18
31-385
9-45
-23
-
5-23
8-60
15-54
68-272
-
-
Typical Size*
Mg/hr
272
272
23
68
23
23
272
9
9
9
272
9
9
23
9
23
23
68
9
9
Model Plant Sizes**
Pertinent to the Industry 1
23,68,136
23,68,136
9,23,68,1
23,68,136
9,23,68
23,68,136
23,68,136
9,23,68
9,23,68
9,23
23,68,136
9,23,68
9,23
9,23,68
9,23
9,23,68
9,23,68
68,75,150
9,23
9,23,68
,272,544,P181
,272,544,P181
36
,272,544
,272
,272,544
,272,544
,272
* These values will be used to estimate the air impact on mass emissions for each industry
** These values will be used to estimate the economic impact on each industry.
***181 Mg/hr portable crushing plant.
Note: In all cases, baghouses are used as the control device(s).
6-6
-------
Table 6.3 Plant Sizes for the Various
Non-Metallic Minerals Industries
(English Units)
Industry
ed & Broken Stone
& Gravel
Salt
im
'im Compounds
;h
:e
"al asphalt &
lated Bitumens
i
te
rspar
tes
spar
3nri te
ite
iculite
ite
Plant
model
used
1
1
2
1
2
2
2
2
2
2
2
2
2
2
2
2
1
1
2
2
Range
(TPH)
15-2400
4-150
-830
-
-225
60-450
5-33
-
6-20
34-425
10-50
-25
-
5-25
9-66
16-60
75-300
-
-
Typical Size
(TPH)
300
300
25
75
25
25
300
10
10
10
300
10
10
25
10
25
25
75
10
10
Model Plant Sizes
Pertinent to the Industry (TPH)
25, 75, 150, 300, 600, P200***
25, 75, 150, 300, 600, P200***
10,25,75,150
25,75,150,300,600
10,25,75
25,75,150,300
25,75,150,300,600
10,25,75
10,25,75
10,25
25,75,150,300,600
10,25,75
10,25
10,25,75
10,25
10,25,75
10,25,75
75,150,300
10,25
10,25,75
hese values will be used to estimate the air impact on mass emissions for each industry.
Tiese values will be used to estimate the economic impact on each industry.
00 TPH portable crushing plant.
: In all cases, baghouses are used as the control device(s).
6-7
-------
7. ENVIRONMENTAL IMPACT
An assessment of the incremental impact to the environment associated
with the application of the emission reduction systems described in Chapter 4
is presented below. Beneficial and adverse impacts on air, water, solid
waste, energy and noise which may be directly or indirectly attributed
to the operation of these emission control systems are assessed.
7.1 AIR POLLUTION IMPACT
To determine the true impact of standards of performance on air
pollution, one must determine the reduction in air pollution they effect
beyond that which would otherwise be achieved by state and local regulations.
As noted in Section 3.2.3, present regulations which limit the emission of
particulate from non-metallic minerals processing facilities take many
forms and vary greatly in stringency and enforcement. For the purpose
of this analysis, it is assumed that all non-metallic minerals plants
are subject to a general process weight regulation designed to limit
particulate emissions from any source. Table 7.1 summarizes the high,
low, and typical emission rates allowed under these State process weight
regulations. An assessment of the national air pollution impact and the
results of dispersion analyses conducted for 12 model plants are presented
below.
7.1.1 National Air Pollution Impact
The production of the various non-metallic minerals is projected to
increase at compounded annual growth rates of up to six percent through the
year 1985. Table 7.2 presents for each non-metallic mineral, the growth
7-1
-------
Table 7.1 Allowable Emissions Under General
State Process Weight Regulations
Process Weight Rate Allowable Emissions, kg/hr (Ib/hr)
10 kg/hr (tons/hr.) High Low Typical
0
2
4
9
18
27
54
90
453
.5
.3
.5
.1
.1
.2
.4
.7
.6
(0.5)
(2.5)
(5.0)
(10.0)
(20.0)
(30.0)
(60.0)
(100.0)
(500.0)
1.
3.
6.
13.
27.
30.
31.
43.
119.
3
5
9
7
1
5
1
2
9
(2.
(7.
(15
(30
(59
(67
(68
(95
8)
7)
-2)
-0)
-7)
-2)
•2)
.2)
(264.0)
0.
2.
2.
4.
5.
7.
15.
13.
18.
7
9
7
0
7
1
1
4
2
(1-6)
(6-3)
(6.0)
(8.7)
(12.5)
(15.6)
(33.3)
(29.5)
(40.0)
1.2
3.4
5.5
8.7
13.9
18.2
21.0
23.2
31.3
(2.6)
(7.6)
(12.0)
(19.2)
(30.5)
(40.0)
(46.3)
(51.2)
(69.0)
7-2
-------
TABLE 7.2 GROWTH RATES AND MINERAL PRODUCTION LEVELS FOR THE
VARIOUS NON-METALLIC MINERALS INDUSTRIES
Mineral
Crushed and broken
stone
Sand and gravel
Clay
Rock salt
Gypsum
Sodium compounds
Potash
Pumice
Natural Asphalt and
related Bitumens
Talc
Boron
Barite
Fluorspar
Feldspar
Pyri tes
Diatomite
Perl i te
Vermiculate
Mica
Kyanite
Total
Estimated
production
103
megagrams
981,839 (1
752,538
52,834
16,482
9,764
5,124
2,629
4,193
99
1,065
1,357
1,301
146
739
367
678
779
364
148
114
1,832,560 (2
1980
level
1,000
tons
,082,292)
(829,531)
(58,240)
(18,168)
(10,763)
(5,648)
(2,898)
(4,622)
(109)
(1,174)
(1,496)
(1,434)
(161)
(815)
(405)
(747)
(859)
(401)
(163)
(126)
,020,052)
Annual2
projected
growth
rate (%)
4.0
1.0
3.5
2.0
2.0
2.5
3.0
3.5
2.0
4.0
5.0
2.2
3.0
4.0
Neg.
5.5
4.0
4.0
4.0
6.0
Estimated
production
103
megagrams
1,194,557 (1
790,926
62,750
18,186
10,783
5,800
3,049
4,980
111
1,296
1,731
1,451
171
900
-
888
948
443
181
153
2,099,304 (2
1985
level
1,000
tons
,316,774)
(871,847)
(69,171)
(20,046)
(11,886)
(6,394)
(3,361)
(5,490)
(122)
(1,428)
(1,909)
(1,600)
(188)
(992)
-
(979)
(1,045)
(488)
(200)
(168)
,314,087)
7-3
-------
rate, the estimated 1980 production level based on the 1975 reported produc-
tion level, and the 1985 estimated production level. Based on the latest
reported (1975) production levels, annual production for all 20 non-metallic
minerals was 1607 x 106 megagrams (1772 x 106 tons) in 1975 and will increase
to 1833 x lo6 megagrams (2020 x 106 tons) in 1980, and 2099 x 106 megagrams
(2314 x 106 tons) in 1985. If one assumes that all existing plants are now
operating at 80 percent of capacity, then new plants and expansions to existing
plants will be required to produce an additional 333 x 106 megagrams (368 x
106 tons) in production capacity projected for the 5-year period from 1980
through 1985. An assessment of the air pollution impact associated with these
capacity additions for each industry segment is presented in Table 7.3.
Process steps included in this evaluation are crushing, grinding, sizing, and
handling. Handling includes conveying, bagging, storage bin loading and fine
product loading. Combustion sources (e.g., dryer or kilns) are not included
in the analysis. The largest tonnage reduction is in the crushed and broken
stone industry followed by the clay industry and the sand and gravel industry.
Reductions in the other industry segments are much smaller.
The following procedure was used to arrive at the numbers listed in
Table 7.3. The values for allowable 1985 emissions under existing State
standards were developed by applying a typical process weight regulation
(see Table 7.1) to a typical plant size (see Table 6.3) for each industry.
Using the additional ore processing capacity installed between 1980 and
1985 the 1985 emissions due to the new facilities were then calculated. (A
plant having both crushing and grinding operations is assumed to be covered by
7-4
-------
TABLE 7.3 SUMMARY OF AIR POLLUTION IMPACT
[megagram/year (ton/year)]
Industry segment
Crushed and broken
stone
Sand and gravel
Clay
Rock salt
Gypsum
Sodium compounds
Potash
Pumice
Natural Asphalt and
related Bitumens
Talc
Boron
Barite
Fluorspar
Feldspar
Pyrites
Diatomite
Perlite
Vermiculite
Mica
Kyanite
Total
Allowable 1985
emissions
Existing ^QS
state regulations /n A?
21,272 (23,448)
3,838 (4,231)
13,978 (15,409)
545 (601)
1,440 (1,587)
945 (1,042)
83 (92)
1,512 (1,666)
23 (25)
444 (489)
74 (82)
288 (317)
48 (53)
309 (341)
0 (0)
301 (332)
119 (131)
25 (28)
63 (69)
76 (84)
45,420 (50,068)
2,923
527
549
35
53
32
83
93
23
28
74
18
9
9
0
11
(7)
3
9
9
4,495
under
irds of
jr/dscf)
(3,222)
(581)
(605)
(39)
(58)
(35)
(92)
(102)
(25)
(31)
(82)
' (20)
(10)
(10)
(0)
(12)
(8)
(3)
(10)
(10)
(4,955)
Reduction
Megagram/
year
18,385 (
3,311
13,430 (
510
1,387
974
0
1,419
0
415
0
269
39
300
0
290
112
23
52
67
impact
(ton/
year)
20,266)
(3,650)
14,804)
(562)
(1,529)
(1,007)
(0)
(1,564)
(0)
(458)
(0)
(297)
(43)
(331)
(0)
(320)
(124)
(25)
(59)
(74)
40,926 (45,113)
7-5
-------
a process weight regulation which is twice that presented in Table 7.1).
The additional ore processing capacity was determined for each industry
by multiplying the additional industry capacity (1985 capacity minus 1980
capacity) by the ore to product ratio for each industry. For industries
such as crushed stone, sand and gravel, clay and talc, the ore to product
ratio is 1.0, most industry values range between 1.0 and 2.0 with a few
[boron (5.8), vermiculite (4.0), fluorspar (3.0), potash (8.2), mica
(4.2)] ranging above 3. The values for allowable 1985 emissions under a
potential NSPS were calculated using the same procedure except that a
gas volume was assigned for the specified plant size and the value 0.05
g/dscm (0.02 gr/dscf) was used to calculate the emission level in terms
of a process weight rate. The reduction impact is the difference between
the allowable 1985 emissions due to the State regulations and the potential
NSPS for new capacity additions.
Assuming that all states enforced standards equivalent to the typical
process weight regulations, capacity additions over the 5-year period
1980-1985 would result in the emission of an additional 45,420 megagrams
(50,068 tons) of particulate in the year 1985. If standards of performance
are promulgated at the level of 0.05 g/dscm (0.02 gr/dscf), then only an
additional 4,495 megagrams (4,955 tons) of particulate emissions would
result. Consequently, the national impact in air pollution reduction
effected by standards of performance if promulgated at the level of 0.05 g/dscm
(0.02 gr/dscf) would be on the order of 40,926 megagrams (45,113 tons) of
particulate in the year 1985. It should be noted that because of the lack
7-6
-------
of uniformity of existing state regulations and the discretionary manner
in which these regulations are enforced, the level of control at existing
plants is very likely below that established by the assumptions that all
existing plants are subject to the typical process weight regulation and
that these regulations are universally enforced. In addition, the air
pollution impact assessed above does not account for that portion of
existing plants which would be replaced with new plants therefore becoming
subject to standards of performance due to obsolescence. As a result, the
true impact would probably exceed that presented above.
7.1.2 Dispersion Analysis
Dispersion calculations were performed on six model plants with typical
production capacities of 9, 23, 68, 136, 272, and 544 megagrams per hour
(10, 25, 75, 150, 300, and 600 TPH). For each model, calculations were performed
for two levels of emission control which included that achievable using best
control technology and that required to meet typical State regulations. A
dry collection system is assumed to be used to meet both levels of control
because: (a) emissions when wet suppression is used are discharged in an
unconstrained manner (not discharged through a stack); and (b) because emission
rates achievable by wet suppression were not determined in this study and are
not otherwise available. Results of the analysis, including characteristics
of the models used and assumptions made, are presented below.
7.1.2.1 Model Plant Characteristics - The model plants selected are identical
to those used in the following chapter in assessing the economic impact. As
in Chapter 8, the 9,23,68 and 136 Mg/hr (10, 25, 75, and 150 TPH) plants are
assumed to use two fabric filters for control and the 272 and 544 Mg/hr
7-7
-------
(300 and 600 TPH) plants are assumed to use three and four fabric filters,
respectively. (One less fabric filter is used in each model plant if a
grinding operation is not employed). It is also assumed that proper
hooding and indraft velocities are used so that all emissions from the
process equipment are captured. Figure 7.1 shows the physical configuration
of the discharge points for each model. For the 9, 23, 68, and 136
Mg/hr (10, 25, 75, and 150 TPH) plants, the No. 1 stack is from a fabric
filter controlling emissions from the crushing operation and its associated
screening and handling operations, and the No. 2 stack is from a second
fabric filter controlling the grinding operation and its associated
screening and handling operations. The 272 Mg/hr (300 TPH) plant is
controlled by three fabric filters; one for the primary crusher, the
second for the remaining crushing operations; (i.e., secondary and
tertiary crushing and screening and associated material handling operations),.
and the third for the grinding system. The 544 Mg/hr (600 TPH) plant is
controlled by four fabric filters; one for the primary crusher, the
second for the secondary crusher and screens, the third for the tertiary
crushers and finishing screens, and the fourth for the grinding system.
The dispersion calculations were performed assuming two levels of emission
control: 0.05 g/rn (0.02 gr/dscf) and the process weight regulation for Ohio
which was chosen as typical of State regulations. The emission source
characteristics for the model plants are presented in Table 7.4. A control
efficiency of about 95 percent would be required to meet the typical process
weight regulation and better than 99 percent to reflect that achievable
using best control.
7-1
-------
SOURCE LOCATIONS
t
N
e
2
(a) 10, 25 and 75 TPH PLANTS
t
N
0
I
e
2
(b) 150 TPH PLANTS
0
50
100 METERS
Figure 7.1 Plant l^outs showing the number and locations of the sources (stacks)
specified for each plant size. The filled circles show the locations
of the individual stacks. The ® symbols show the origins of the
receptor grids used in the model calculations.
7-9
-------
SOURCE LOCATIONS
t
N
o • «
I 2 3
(c) 300 TPH PLANTS
t
N 3
(d) 600 TPH PLANTS
50 100 METERS
Figure 7.1 (continued)
7-lo
-------
Table 7.4
STACK AND EMISSIONS DATA
(Metric Units)
Case3
1
2
3
4
5
6
7
8
9
10
11
12
Plant
Size
(Mg/hr)
9
9
23
23
68
68
136
136
272
272
544
544
Stack
Number
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
3
1
2
3
1
2
3
4
1
2
3
4
Stack
Diameter
(m)
0.58
0.33
0.58
0.33
0.61
0.37
0.61
0.37
0.76
0.43
0.76
0.43
0.79
0.55
0.79
0.55
0.58
1.07
0.76
0.58
1.07
0.76
0.61
0.91
0.91
1.10
0.61
0.91
0.91
1.10
Stack
Height
(m)
9.1
12.2
9.1
12.2
9.1
12.2
9.1
12.2
9.1
12.2
9.1
12.2
9.1
12.2
9.1
12.2
6.1
9.1
12.2
6.1
9.1
12.2
6.1
9.1
9.1
12.2
6.1
9.1
9.1
12.2
Stack
Exit
Velocity
(m/sec)
18.0
23.0
18.0
23.0
18.0
23.0
18.0
23.0
18.0
23.0
18.0
23.0
23.0
23.0
23.0
23.0
15.0
23.0
23.0
15.0
23.0
23.0
15.0
23.0
23.0
23.0
15.0
23.0
23.0
23.0
Stack
Exit
Temperature
(°K)
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
Parti cul ate
Emission
Rate
(g/sec)
0.24
0.09
2.42
2.42
0.27
0.11
4.46
4.46
0.41
0.15
6.10
6.10
0.58
0.26
6.74
6.74
0.18
0.92
0.52
1.52
6.06
6.10
0.21
0.74
0.71
1.04
1.11
3.84
3.96
6.72
o
Odd numbered cases are based on an emission level of 0.05 g/m (0.02 gr/dscf).
Even numbered cases are based on allowable emissions if typical State process
weight regulations are used.
7-11
-------
Table 7.4
STACK AND EMISSIONS DATA
(English Units)
Case9
i
i
2
3
4
5
6
7
8
9
10
11
12
Plant
Size
(tph)
* -i _ *
10
10
25
25
75
75
150
150
300
300
600
600
Stack
Number
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
1
2
3
1
2
3
1
2
3
4
1
2
3
4
Stack
Diameter
(ft)
1.9
1.0
1.9
1.0
2.0
1.2
2.0
1.2
2.5
1.4
2.5
1.4
2.6
1.8
2.6
1.8
1.9
3.5
2.5
1.9
3.5
2.5
2.0
3.0
3.0
3.6
2.0
3.0
3.0
3.6
Stack
Height
(ft)
30
40
30
40
30
40
30
40
30
40
30
40
30
40
30
40
20
30
40
20
30
40
20
30
30
40
20
30
30
40
Stack
Exit
Velocity
(ft/min)
356
455
356
455
356
455
356
455
356
455
356
455
455
455
455
455
300
455
455
300
455
455
300
455
455
455
300
455
455
455
Stack
Exit
Temperature
(°F)
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
ambient
Parti cul
Enrissfi
Rate
(Mr
1.9
0.7
19.2
19.2
2.1
0.9
35.4
35.4
3.3
1.2
48.4
48.4
4.6
2.1
53.5
53.5
1.4
7.3
4.1
12.1
48,. 1
48.4
1.7
5.9
5.6
8.3
8.8
30.5
31.4
53.3
Odd numbered cases are based on an emission level of 0.05 g/m3 (0.02 gr/dscf).
Even numbered cases are based on allowable emissions if typical State process
weight regulations are used.
7-12
-------
7.1.2.2 The Dispersion Model and Meteorological Considerations - The
dispersion model used to analyze the air pollution impact of the plants
described above is the modified Single-Source (CRSTER) Model developed by
the Meteorology and Assessment Division, EPA. The dispersion analysis was
performed by H. E. Cramer Company, Incorporated.
A preliminary analysis showed that maximum short-term ground-level
concentrations produced by emissions from stacks of the type listed in
Table 7.4 are most likely to occur during periods of light-to-moderate wind
speeds and persistant wind directions in combination with neutral stability.
These meteorological conditions are quite common in the Pittsburgh,
Pennsylvania area. Also, non-metallic minerals processing plants are located
in the vicinity of Pittsburgh. Consequently, it was decided that the surface
and upper-air meteorological data for the Greater Pittsburgh Airport were
representative and should be used to develop the meteorological inputs
required for the dispersion-model calculations. Because the plants are
assumed to be located outside the Pittsburgh urban area, a rural location was
assumed in the model calculations. The prevailing wind directions in the
Pittsburgh area during periods of neutral D stability are from the west.
In order to maximize the superposition of plumes from individual sources
under worst-case meteorological conditions, all plant configurations were
given an east-west orientation (see Figure 7.1).
The results of the preliminary analysis also showed that the maximum
short-term ground-level concentrations produced by emissions from the
sources listed in Table 7.4 can be expected to occur at downwind distances
7-13
-------
ranging from less than 300 meters (330 yards) to about 900 meters (985 yards).
The property boundaries of the six plants are assumed to be a minimum distance
of 300 meters from any stack. For the purposes of this study, only ground-
level particulate concentrations that occur at and beyond the plant property
boundaries were used in assessing the air quality impact of plant emissions,
From a consideration of the results of the preliminary analysis and
the fact that only off-property ground-level particulate concentrations
are of concern, two receptor grids were constructed for calculations. The
©symbols in Figure 7-1 show the origins of these receptor grids. The
receptor grid used in the model calculations for the 9, 23, 68, and 136 Mg/hr
(10, 25, 75, and 150 TPH) plants comprised seven concentric receptor rings with
radii of 0.335, 0.4, 0.5, 0.6, 0.8, 1.0 and 1.5 kilometers (366, 437, 547,656,
875, 1094, and 1640 yards). The receptor grid used in the model calcu-
lations for the 272 and 544 Mg/hr (300 and 600 TPH) plants comprised six
concentric receptor rings with radii of 0.38, 0.5, 0.6, 0.8, 1.0 and 1.5 kilo-
meters (415, 657, 656, 875, 1094 and 1640 yards). All receptor grid points wers
assumed to be at the same elevation as plant grade. Thus the only terrain
effects included in the model calculations are those implicitly contained in
the meteorological data from the Greater Pittsburgh Airport.
7.1.2.3 Results and Discussion of Dispersion Calculations - Maximum 24-hour
average and annual-average concentrations are presented in Tables 7.5 & 7.6.
All 24-hour and annual maximums were located at either 0.3 or 0.4 kilometer
(328 or 437 yard) from the plant. Generally, for each case, less than 10
7-14
-------
Table 7.5
ESTIMATED MAXIMUM 24-HOUR AND ANNUAL GROUND-LEVEL PARTICULATE
CONCENTRATION DUE TO EMISSIONS FROM THE PROCESS
SOURCES IN THE MODEL NON-METALLIC MINERALS PLANTS
HAVING BOTH CRUSHING AND GRINDING OPERATIONS
24-Hour Average Annual Average
Distance to Maximum Distance to Maximum
Plant Size Maximum Concentration Maximum Concentration
[Mg/hr (tons/hour)] Case (Km) (yg/m ) (Km) (y g/m )
9 (10)
23 (25)
68 (75)
136 (150)
272 (300)
544 (600)
1
2
3
4
5
6
7
8
9
10
11
12
0.3
0.3
0.3
0.3
0.3
0.3
0.4
0.3
0.4
0.4
0.4
0.4
14
200
15
354
20
430
24
383
40
279
64
363
0.2
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.4
0.4
0.4
0.4
2
16
2
28
2
34
2
31
4
27
5
28
q
Odd number cases are based on an emission level of 0.05 g/m (0.02 gr/dscf).
Even number cases are based on allowable emissions under typical State process
weight regulations (as shown in Table 7.1)
7-15
-------
Table 7.6
ESTIMATED MAXIMUM 24-HOUR AND ANNUAL GROUND-LEVEL PARTICULAR
CONCENTRATION DUE TO EMISSIONS FROM THE PROCESS
SOURCES IN THE MODEL NON-METALLIC MINERALS PLANTS
HAVING ONLY CRUSHING OPERATIONS
24-Hour Average Annual Average!
Distance to Maximum Distance to
Plant Size Maximum Concentration Maximum Concerto
[Mg/hr (tons/hour)] Case9 (Ktn) (yg/m ) (Km)
9 (10)
23 (25)
68 (75)
136 (150)
272 (300)
544 (600)
1
2
3
4
5
6
7
8
9
10
11
12
0.3
0.3
0.3
0.3
0.3
0.3
0.4
0.3
0.4
0.4
0.4
0.4
10
107
11
191
15
223
16
187
29
208
48
259
0.2
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.4
0.4
0.4
0.4
1
8
1
14
1
17
1
15
3
16
4
20
•D
Odd number cases are based on an emission level of 0.05 g/m (0.02 gr/dscf).
Even number cases are based on allowable emissions under typical State process
weight regulations (as shown in Table 7.1)
7-16
-------
percent of the days per year had 24-hour average concentrations exceeding
70 percent of the maximum concentration shown in the Table.
The national primary ambient air quality standards for particulate
matter, as published in the Federal Register, Volume 36, No. 84, April 30,
1971, are:
a. 75 micrograms per cubic meter—annual geometric mean;
b. 260-micrograms per cubic meter—maximum 24-hour concentration not
to be exceeded more than once a year.
Assuming a pristine atmosphere, the data presented in Table 7.5 indicate that
for all cases, excluding emissions from sources other than the stack, a
o
plant meeting an emission limitation of 0.05 g/m (0.02 gr/dscf) would meet
the ambient air quality standards. In comparison, any plant with a pro-
duction rate above 9 Mg/hr (10 TPH) which just meets the typical process
weight regulation, even though it may require a 95 percent reduction from
uncontrolled levels would exceed the ambient air quality standards for
the 24-hour average.
The dispersion results presented are only for plant process facilities
under consideration. Process operations common to most plants which are not
covered by the proposed standard include drilling, blasting, loading at the
mine, hauling, stockpiling, conveying (other than transfer points), and
windblown dust from stockpiles, roads, and plant yards. These operations
7-17
-------
are not included because they are not amenable to control using the emission
control techniques upon which the proposed standards are based. They are,
however, significant sources of particulate matter emissions. Methods for
controlling emissions from these operations are discussed in the document
entitled "Air Pollutant Control Techniques for the Crushed and Broken
Stone Industry" available from the EPA Library (MD-35), Research Triangle
Park, North Carolina 27711, telephone number (919) 541-2777.
7.2 WATER POLLUTION IMPACT
The almost exclusive utilization of dry collection techniques (particu-
late capture combined with a dry emission control device) for control generates
no water effluent discharge. In cases where wet dust suppression techniques
could be used, the water adheres to the material processed until it evaporates,
Wet suppression systems, therefore, would not result in a water discharge.1*
Consequently, emission standards for the non-metallic minerals industry will
have no water pollution impact.
7.3 SOLID WASTE DISPOSAL IMPACT
Disposition of quarry, plant and dust collector waste materials depends
somewhat upon State and local government and corporate policies. When
fabric filter systems are used, about 1.4 megagrams (1.6 tons) of solid waste
*
are collected for every 250 megagrams (278 tons) processed. In many
cases this material can be recycled back into the process, sold, or used
for a variety of purposes.
Where no market exists for the collected fines, they are typically
disposed of in the mine or in an isolated location in the quarry. A 544 Mg/hr
(600 TPH) crushing plant using dry collection for control would generate about
*Estimate based on the difference between controlled and uncontrolled
OITITCCTr\r» 4-tio4-/~v\rt(-
emission factors.
7-18
-------
27.6 megagrams (30 tons) of waste over an eight hour period. This is about
0.5 percent of the plant throughput. Generally, the collected fines are
discharged to a single haul truck at the end of the day and transported
to the quarry for disposal. This dumping and transporting can be a
source of fugitive dust if these operations are not protected from the
wind or controlled by wet suppression. No subsequent air pollution
problems should develop provided the waste pile is protected from wind
erosion.
Consequently, it is EPA's judgment that the application of dry
controls in the non-metallic minerals industry will not have a sig-
nificant solid waste disposal impact. Where wet dust suppression can be
used, no solid waste disposal problem exists over that resulting from
normal operation.
7.4 ENERGY IMPACT
The implementation of standards of performance for the non-metallic
minerals industry will necessarily result in an increase in energy
usage. Generally, the energy impact of alternative control systems and
standards is assessed by determining the additional energy consumption
(type and amount) above that which would be necessitated by existing
State regulations. For the non-metallic minerals industry, however,
because of the non-uniformity of current State regulations and the
degree of interpretation necessary for enforcement, such an approach
would likely substantially understate the true impact on the industry.
An alternative approach is to assess the energy impact against an
7-19
-------
estimate of the current status (type and extent) of existing control
across the industry. Because of the size of this industry, however, any
such estimates for the non-metallic minerals industry would be subject
to considerable uncertainty. Consequently, the energy impact analysis
presented below, like the economic impact analysis presented in Chapter 8,
is gauged against an assumed baseline existing control of "no control."
In this way, the resultant energy impact will have a liberal bias which,
if determined to be reasonable, will assure that the true impact is not
adverse.
The energy requirements both with and without air pollution controls
for six typical plant sizes are shown in Tables 7.7 and 7.8. The model
plants selected are identical to those used for the cost and dispersion
analyses. The energy requirements reported are for plants with both
crushing and grinding operations (Table 7.7) and for plants having
crushing operations only (Table 7.8).
A 9 Mg/hr (10 TPH) plant with both crushing and grinding operations
and with no controls would require motors with horsepower rating totaling
about 214 Kw (287 hp) to operate. Complete fabric filter control would
require an additional 30 Kw (40 hp), or an increase in plant power
consumption of about 14 percent. For the 23 to 544 Mg/hr (25 to 600
TPH) plants, the application of a dry collection system would increase
power consumption by about 5 to 10 percent.
7-20
-------
Table 7.7 ENERGY REQUIREMENTS FOR MODEL NON-METALLIC
MINERALS PLANTS HAVING CRUSHING AND GRINDING OPERATIONS
[KILOWATTS (HORSEPOWER)]
Plant Size Fabric Filter Percent Energy Increase
[Mq/hr (TPH)]
9 (10)
23 (25)
68 (75)
136 (150)
272 (300)
544 (600)
Uncontrolled
214 (287)
353 (473)
908 (1218)
1584 (2124)
3016 (4045)
5810 (7792)
Controlled
244 (327)
387 (519)
966 (1296)
1666 (2234)
3170 (4252)
6098 (8177)
(«)
13.9
9.7
6.4
5.2
5.1
4.9
Table 7.8 ENERGY REQUIREMENTS FOR MODEL NON-METALLIC
MINERALS PLANTS HAVING CRUSHING OPERATIONS ONLY
[KILOWATTS (HORSEPOWER)]
Plant Size
[Mg/hr (TPH)]
9 (10)
23 (25)
68 (75)
136 (150)
272 (300)
544 (600)
Uncontrolled
102 (137)
129 (173)
312 (418)
391 (524)
630 (845)
1038 (1392)
Fabric Filter
Controlled
123 (165)
153 (205)
356 (478)
450 (604)
737 (989)
1232 (1652)
Percent Energy Increase
(*)
20.4
18.5
14.4
15.4
17.0
18.7
7-21
-------
For the 9 to 544 Mg/hr (10 to 600 ton/hr) plants with only
crushing operations, the application of a dry collection system would
increase power consumption between 14 and 20 percent. It is interesting
to note that a 544 Mg/hr (600 ton/hr) crushing plant using a combina-
tion of both wet and dry controls sufficient to meet most existing State regu-
lations would likely require an additional 75 kW (100 hp) or about a 7
percent increase in power consumption. Complete fabric filter control
for this same plant would require a 7 percent increase in power
consumption when compared to a plant achieving the typical State
regulations.
The estimated additional energy requirement to meet the added
demand for non-metallic minerals projected for the year 1985 would be
about 0.805 million megawatt-hours in the absence of any air pollution
controls. In contrast, if fabric filter controls were installed on all
capacity additions (including those obtained from new plants and expansions
to existing plants), the estimated additional energy demand would
increase to about 0.928 million megawatt-hours. Consequently, the net
increase in energy consumption for the year 1985 which would result from
the installation of emission control would be about 0.123 million megawatt-
hours or 15 percent over that which would otherwise be required to meet
the projected capacity additions without controls. When compared to
forecasts for national demand of electrical energy alone in 1985 (4.1
billion megawatt-hours), this resultant increase in energy consumption
7-22
-------
is equivalent to approximately 3 x 10~3 percent of that projected to be consumed
nationally.6
In addition, the energy impact on each of the 20 affected non-metallic
industries has been calculated in Table 7.9. The impacts of energy usage of
controlled versus uncontrolled new facilities was calculated to be 0.123
million megawatts for the year 1985. The resultant increase in particulate
emissions generated by power plants in the production of the additional
0.123 million megawatts of required power for the control equipment was
calculated to be 51 Mg/year (56 ton/year) in 1985 using the allowable
emission rate standard of 0.03 lb/106 Btu input. It is concluded, therefore,
that this increase of particulate emissions from power plants would be more
than offset by the potential savings in particulate emissions generated by the
non-metallic industry under an NSPS (41,000 Mg/year or 45,000 ton/year
particulate).
7.5 NOISE IMPACT
When compared to the noise emanating from crushing and grinding process
equipment, any additional noise from properly designed exhaust fans for the
control system will be insignificant. Consequently, no significant noise
impact is anticipated due to the implementation of standards of performance
for non-metallic minerals plants.
7-23
-------
TABLE 7.9 ENERGY IMPACT ON INDIVIDUAL NON-METALLIC INDUSTRIES UNDER PROPOSED NSPS
Industry
Crushed stone
Sand and gravel
Clay
Rock salt
Gypsum
Sodium compounds
Potash
Pumice
Natural Asphalt and
Related Bitumens
Talc
Boron
Barite
Fluorspar
Feldspar
Pyrite
Vemriculite
Mica
Kyanite
Diatomite
Perl i te
Total
Increased
capacity 1980-1985
103 Mg/yr
212,718
38,388
9,916
1,704
1,019
676
420
787
12
231
374
150
25
161
0
210
169
79
33
39
(267,111)
(103 ton/yr)
(234,481)
(42,316)
(10,931)
(1,878)
(1,123)
(745)
(463)
(868)
(13)
(255)
(412)
(165)
(28)
(177)
(0)
(231)
(186)
(87)
(36)
(43)
(294,738)
Typical plant
size
Mg/hr
272
272
23
68
23
23
272
9
9
9
272
9
9
9
23
68
9
9
23
23
(ton/hr)
(300)**
(300)**
(25)
(75)**
(25)
(25)
(300)
(10)
(10)
(10)
(300)
(10)
(10)
(10)
(25)
(68)**
(10)
(10)
(25)
(25)**
additional typical
plants required
391
71
52
13
5
3
0
10
0
3
0
1
1
1
0
1
3
1
1
1
558
Energy required
per typical
con PO(^
737
737
387
356
387
387
3,170
244
244
244
3,170
244
244
244
387
356
244
244
387
153
Energy required
per typical
uncontrolled plant
(kW)
630
630
353
312
353
353
3,016
214
214
214
3,016
214
214
214
353
312
214
214
353
128
Impact on
each industry
(kW)
41,837
7,597
1,768
572
170
102
0
300
0
90
0
30
30
30
0
44
90
30
34
25
52,749
*Based on plant operating schedule of 8,400 hours/year.
**Based on plant operating schedule of 2,000 hours/year.
-------
REFERENCES FOR CHAPTER 7
1. "Analysis of Final State Implementation Plans - Rules and Regulations,"
APTD-1334, EPA Contract No. 68-02-0248, July 1972, pp. 29-31.
2. Commodity Data Summaries Annual, 1977, U. S. Bureau of Mines.
3. "Dispersion - Model Analysis of the Air Quality Impact of Particulate
Emissions From Non-Metallic Minerals Processing Plants," prepared
by H. E. Cramer Company, Incorporated, for the U. S. Environmental
.Protection Agency, December 1976.
4. "Draft Development Document for Effluent Limitations Guidelines and
Standards of Performance - Mineral Mining and Processing Industry -
Volume I (Minerals for the Construction Industry), prepared by Versar,
Incorporated, for the U. S. Environmental Protection Agency, Contract
No. 68-01-2633, January 1975, p. V-3.
5. "Source Testing Report - Essex Bituminous Concrete Corporation,
Dracut, Massachusetts," prepared by Roy F. Weston, Incorporated, EPA
Report No. 75 STN-2, December 27, 1974.
6. Dupree, Walter G., and West, James A., "United States Energy
through the Year 2000," U. S. Department of the Interior,
December, 1972, p. 19.
7-25
-------
8. ECONOMIC IMPACT
8.0 SUMMARY
The effect of NSPS control costs on the 20 non-metallic minerals industries
was evaluated by first screening each industry for potentially significant
impacts. A potentially significantly impacted industry was considered to be
any industry which had a plant whose per unit production cost could be increased
by 2% or more because of NSPS control costs. This screening analysis consisted
of measuring the effect of annualized control cost for the smallest size model
plant in each industry (therefore the highest per unit control cost and worst
case situation) on the average selling price of the mineral. On the basis of
this screening six minerals were selected for further evaluation:
• Pumice
• Sand and gravel
• Crushed stone
• Common clay
• Gypsum
• Perlite
These six minerals were evaluated by developing a discounted cash flow
(DCF) analysis for each model new plant size in each industry and also for
expansion plant sizes in the common clay and gypsum industries. DCF is an
investment decision analysis which shows the economic feasibility of a
planned capital investment project over the life of the project.
The DCF analysis was conducted by using primarily "worst case" assump-
tions. Assumptions used include:
8-1
-------
• the total of NSPS control costs were incremental
costs; i.e., that there are no SIP control costs
that a plant would have to incur in the absence
of NSPS control.
• the production volume is constant through the life
of the project except for the crushed stone
plant where it is assumed that they operate at
50% of capacity for the first year.
• NSPS control cost pass through is limited by
competition of existing plants in the same
industry which do not have to meet the NSPS
standard.
• the new plant operates as a separate business
entity and cannot expect to finance the control
from another business activity or parent firm.
For new plants Table 8.41 shows that the 9 and 23 Mg/hr (10 and 25 tph)
planys in sand and gravel, and crushed stone, and the 9 Mg/hr (10 tph) plants
in common clay and pumice are likely to be significantly impacted by the NSPS.
The DCF model was not able to determine a clear positive or negative invest-
ment decision for the 9 Mg/hr (10 tph) gypsum, 23 Mg/hr (25 tph) clay and
68 Mg/hr (75 tph) pumice, sand and gravel and crushed stone plant sizes.
However, in view of the conservative assumptions used, they were judged to
be economically feasible. All of the other plant sizes in the six industries
are likely to be economically feasible after the promulgation of NSPS.
Table 8.42 shows that the DCF analysis produced an economically feasible
result for all expansion size plants except for the 4.5 Mg/hr (5 tph) common
8-2
-------
clay plant where the investment decision result was unclear. However, in
view of the conservative assumptions used, it was judged to be economically
feasible.
For the 14 industries for which a DCF was not performed new plant
construction would be feasible for all plant sizes because the greatest
potential NSPS control cost absorption is equal to or less than 2% of the
product price. Furthermore, for the other minerals where the potential control
cost absorption was greater than 2% the DCF analysis produced an economically
feasible result.
New regulations shall be considered a major action if "additional annual-
ized cost of compliance, including capital charges (interest and depreciation),
will total $100 million (i) within any one of the first 5 years of implementa-
tion, or (ii) if applicable, within any calendar year up to the date by which
the law requires attainment of the relevant pollution standard," or "the total
additional cost of production of any major industry product or service will
exceed 5% of the selling price of the product." Total industry annualized
control costs in the fifth year after promulgation of NSPS and control costs
as a percent of selling price are lower than the guidelines set for these
measures of $100 million and 5%, respectively. Consequently, the proposed
standards for the non-metallic minerals processing industry would not be
considered a routine action and not a major one.
80
-0
-------
8.1 UNITED STATES NON-METALLIC MINERALS INDUSTRY STRUCTURE
8.1.0.1 Introduction
The non-metallic minerals are numerous and range from such bulk
commodities as sand and gravel and stone, the annual domestic demand
for which is quoted in billions of short tons, down to industrial diamonds
and gem stones, which are measured in carats. The last three decades of
this century will be a period of rapid growth for the non-metallic mineral
industries. The requirements for new buildings, road construction, rehabili-
tation of blighted cities, food production, chemical manufacture, ceramics,
metal working, and the host of other established uses of non-metals can be
expected to increase in volume. Of equal long-term significance are the
opportunities to supplement and replace metals as they become scarce and
expensive. Development of performance specifications will expand the use
of composites of metals, non-metals, and non-mineral materials in new and
improved end products. Research leading to significant improvements in the
properties of the abundantly available non-metals also will enhance their
utility.
The domestic non-metallic mineral industries, with a few exceptions,
should be able to provide adequate supplies from domestic sources at reasonable
costs to the year 2000. For the exceptions, supplies can be obtained from
foreign sources or alternatives such as substitutes. However, the maintenance
of a high degree of domestic self-sufficiency will require solution of many
technical and economic problems. For some commodities, such as kyanite,
synthesis from domestic raw materials offers a feasible solution to supply
problems. Increased recovery of by-products, improvement of technology
8-4
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enabling use of lower grade reserves, and improvements in production and
transportation facilities and costs are other means of enhancing the domestic
supply position.
Serving, as non-metal lies do, extremely heterogeneous markets, there
is less tendency toward vertical and horizontal integration than in some of
the metallic and fuel categories. However, there are advantages of scale and
organization to be gained in some of the larger industries so there has been
some consolidation among producers serving the construction and fertilizer
fields. Continuation of this trend may be expected where efficiency benefits
can be achieved.
-,-Warren E. Morrison and Robert E. Johnson, Jr., from Mineral Facts and
Problems: 1970 Edition.
The industry structures which follow for the twenty non-metallic minerals
being considered here have been prepared to provide background information to
assist in the development of atmospheric emission limits under Federal New
Source Performance Standards (NSPS) for industry processes.
In order to maintain as high a degree of consistency as possible for
non-metallic minerals considered here across the years 1972-1976, statistical
and analytical data presented is derived or cited from U.S. Bureau of Mines
documents in most every instance and supplemented with significant data from
other sources when necessary.
Each of the individual industry structures is based on the general
outline that follows:
8-5
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INDUSTRY STRUCTURE
1. General
Mineral(s) description coverage of the analysis
2. Plants-define
e number and employment
• size
• geographic distribution
3. Companies , ,
9 number
t concentration
4. Industry Statistics
t Production
e Consumption
Prices
Imports
Exportd
Stocks
Employees
All items of information noted in the outline are not available for some
individual industries.
The 20 non-metallic minerals being considered here have been grouped
into three classifications by end-use. In order of group production volume,
they are as follows:
8.1.1 - Non-Metallic Minerals for Construction and Industrial Uses
8.1.1.1 Sand and Gravel
8.1.1.2 Crushed Stone
8.1.1.3 Gypsum
8.1.1.4 Pumice
8.1.1.5 Diatomite
8.1.1.6 Perlite
8.1.1.7 Vermiculite
8.1.1.8 Mica
8.1.1.9 Natural Rock Asphalt
8-6
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8.1.2 - Non-Metallic Minerals for the Chemical and Fertilizer Industries
8.1.2.1 Barite
8.1.2.2 Flourspar
8.1.2.3 Salt
8.1.2.4 Potash
8.1.2.5 Sodium Compounds
8.1.2.6 Boron
8.1.2.7 Pyrites
8.1.3 - Non-Metallic Minerals for Clay, Ceramic and Refractory Industries
8.1.3.1 Clays
8.1.3.2 Talc
8.1.3.3 Feldspar
8.1.3.4 Kyanite
Each section includes a summary table illustrating salient industry
statistics estimates for 1976 obtained from the U.S. Bureau of Mines Commodity
Data Summaries Annual for 1977. In some cases 1975 and 1976 data is not yet
available and more complete data from former years has been used.
8.1.1 NON-METALLIC MINERALS FOR CONSTRUCTION AND INDUSTRIAL USES
8.1.1.1 Sand and gravel
Sand and gravel has been, and will continue to be, the principal con-
struction material in the United States. It exceeds the use of crushed stone
in construction by about 222 million Mg or 245 million short tons (1974).
Sand and gravel has the lowest average unit value of all mineral commodities,
and it is one of the fastest growing mineral producing industries in the
United States.
8.1.1.1.2 U.S. Plants
In 1976, there were an estimated 7,000 sand and gravel operations.
The individual sand and gravel operations range in size from those producing
over 3.6 million Mg (4 million tons) annually to those reporting production
8-7
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less than 4335 Mg (5,000 tons). In 1974, 23 percent of total production was
from 89 operations producing .9 million Mg (1 million tons) or more, but 58
percent was produced by 6,604 operations in the range from 45,350 to 453,500 Mg
(50,000 to 500,000 tons) per year.
The sand and gravel industry is highly mechanized and employs an esti-
mated 50,000 men. About 90 percent are production workers and the balance
are clerical, maintenance, and other staff personnel.
Output of sand and gravel has grown at a faster rate than employment
for the past two decades, reflecting an increase in productivity. Average
output has almost doubled from 4.08 Mg (4.5 tons) per man-hour in 1949 to
nearly 8.2 Mg (9 tons) per man-hour in 1973. This increase in productivity
has to date been adequate to compensate for the increasing hourly cost of
labor and higher costs for equipment, land acquisition, rehabilitation and
other factors related to production.
Because of its low unit value it is necessary to produce sand and gravel
near the point of use; therefore, geographically the sand and gravel industry
is concentrated in the large, rapidly expanding urban areas and, on a transi-
tory basis, in areas where highways, dams, and other large-scale public and
private works are under construction. The largest operations tend to be
concentrated in States with the largest total production, yet production of
sand and gravel is so widespread many firms and plants are involved.
In 1974, of 89 sand and gravel operations with an annual production of
.9 million Mg (one million tons) or more, 18 were located in California.
8-1.1.1.3 U.S. Companies^
Sand and gravel operations were owned by 4,700 companies in 1976.
Producers may be large or small, public or private, turning out one product
8-8
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or a range of products, sell bank-run material or subject their material
to processing. The average company produces 22 Mg/hr (250 TPH).
8.1.1.1.4 U.S. Production, Consumption and Prices
Production of common varieties of sand and gravel is tied very closely
to activity in the consuming industries, principally construction of all
general types. Production of special qualities of sand is associated
chiefly with the needs of the glass industry and foundries. Sand and
gravel production, consumption and other industry statistics are presented
in Table 8-1. Table
J~1 SAND AND GRAVEL: SALIENT STATISTICS
e/
Salient Statistics—United States 1972 1973 1974 1975 1975'
PrntinrMnn 829,292 892,152 820,514 716,015 698,390
(914,324). (983,629) (904,646) (789,432) (770,000)
ImDorf,. 690 725 357 339 226
1P (761) (800) (394) (374) (250)
Exports 1,651 1,581 2,046 2,919 3,265
(1,821) (1,744) (2,256) (3,219) (3,600)
.„„,,-„, rnnc.rtmti,, 828,330 891.295 818,825 713,434 695,331
Apparent consumption (913,264) (982,685) (902,784) (786,587) (766,650)
Price $/Mg (dollars per ton) 1.52 1.52 1.73 1.97 2.18
(1.38) (1.38) (1.57) (1.79) (1.98)
Stocks, year end Not available
Employment: Mine e/ 43'°°° 49'°°° 39-°°° 36'000 34'000
Source: Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines)
The highway and general building construction industries are the greatest
consumers of sand and gravel. As such, construction activity virtually deter-
mines the demand and supply of sand and gravel for any given period. During
1976, approximately 97 percent of the total U.S. sand and gravel output was
used in the construction industries.
Construction will continue to dominate the end-use picture for sand and
gravel. Industrial sand and gravel, although important, will constitute only
a small percentage of the total volume of domestic sand and gravel requirements.
Labor, energy (electricity, fuel oil, and gasoline), and water are the
major requirements for the production of marketable sand and gravel products.
Actual operating costs for production are variable. Production costs vary widely
depending upon geographic location and composition of deposits.
8-9
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8.1.1.2 Crushed Stone
8.1.1.2.1 General
Crushed stone is a term used to describe a rock which has been reduced
in size after mining to meet various consumer requirements. The rock
may meet any one of many minerological definitions, including limestone,
granite, trap rock, and others. The stone industry is the largest non-
fuel, non-metallic mineral industry in the United States from the stand-
point of total value of production and is second only to sand and gravel
in volume produced.
8.1.1.2.2 U.S.,Plants
There are currently 5,400 crushed stone quarries in the United States
as reported by the Bureau of Mines. Of these, approximately 2,300 are
considered by the Bureau of the Census (SIC's 1422, 1423, and 1429)
to be commercial operations primarily concerned with the production of
crushed stone. The remaining 3,100 consist of quarries operated by
federal, state, and local governments, quarries that are part of integrated
(cement, lime, etc.) operations, quarries operated on a temporary basis by
establishments not concerned primarily with the production of stone (e.g.,
highway contractors, SIC 1611), and small quarries operated without paid
employees but proprietor-operated. Some of these latter categories enter
and re-enter the market. The 5,400 quarries are served by approximately
4,000 plants.
Included in the Bureau of Mines data, but not in the Census data, are
portable crushing plants. These plants, which number 1,700 constitute a
8-10
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good portion of those plants referred to above which are attached to either
the federal government or highway contractors, and which may enter or
re-enter the market on an irregular basis. They also service small quarries
in rural areas for a short period each year, sufficient to crush and stock-
pile a community's immediate needs.
8.1.1.2.3 U.S. Companies
The crushed stone industry is comprised of a large number of small,
locally owned firms which account for a minor proportion of national pro-
duction, and a small number of larger firms which are regionally or nationally
diversified, and account for a large percentage of the national production.
Patterns of firm ownership are similar to those in other sectors of
the construction-oriented basic materials industries. At one extreme
there are the small local operations, often operated as proprietorships,
where the plant manager and the owner are one and the same person. At the
other extreme are the plants owned by major firms for whom the crushed
stone business is but one part of a number of fields of enterprise.
Plant managers for these firms rarely have an equity interest in the firm
for which they work, being regular employees whose tenure at a particular
quarry may be temporary in nature.
In 1976 crushed stone was produced by 2,000 companies at 5,400
quarries in 49 states for dense graded roadbase stone, concrete aggregate,
roadstone, cement, bituminous aggregate, and other uses. Leading states
were Illinois, Pennsylvania, Texas, Missouri, and Ohio, which accounted
for 30% of the total production. Output decreased 1% to 806 million Mg
million tons) values at $2.02 billion. Of the total, 74% was limestone,
10% was granite, and 9% was traprock.
8-11
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8.1.1.2.4 U.S. Production, Consumption. Prices
Salient industry statistics are presented in Table 8-2,
Table Q—9 U.S. CRUSHED STONE INDUSTRY (in thousand
^ Hg and thousand short tons in parentheses)
1972-*— 1973 1974 1975 1976 e/
Production 835 962 946 819 807
(920) (1,060) (1,043) (903) (890)
Imports for consumption 44444
(4) (.4) , (4) (4) (4)
Exoorts 23333
P (2) (3) (4) (4) (4)
Apparent consumption 836 962 946 819 807
(922) (1,061) (1,043) (903) (890)
Average price:
Crushed stone $1.88 $1.97 $2.19 $2.57 S2.61
(J1.72) ($1.80) ($2.00) ($2.35) ($2.39)
Stocks, year-end Not Available
Employment; Quarry 64,000 64,000 64,000 55,000 54,000
8, mill e_/
Source- Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines.
End Uses
The end uses for crushed stone are many and varied but construction
and construction-related applications account for at least 80% of total
shipments. Crushed stone is either used directly in its natural state or
is shipped for further processing into miscellaneous manufactured products.
In its natural state, stone is an important ingredient for highway
and street construction where it can form the base of the road, be included
in the concrete or bituminous pavement as an aggregate or be used as an
anti-skid material for surface treatment. As an aggregate in other types
of concrete, stone is sold to ready-mix and precast concrete manufacturers
as a basic ingredient for structural concrete.
Future Growth
The long-term historic rate of growth (1963-1972) for crushed stone
has been at an annual rate of 3.3%. This rate of growth will probably
modify somewhat over the remainder of the decade, partly because the rate
8-12
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of construction expenditures will reduce from 2.1% over the same period
to no more than 2.0% from 1972 to 1980, but also because the industry
has reached a stage of mature stability with respect to product substi-
tutions. The rate of construction growth will be slower due to a combi-
nation of inflationary, energy and recessionary factors impacting business
and individuals, as well as the fact that base year 1972 was a strong one
for construction activity. We thus anticipate that crushed stone consump-
tion will grow at about 3% per year compounded to 1980 from 1974 on a tonnage
basis. Limestone and granite will both increase their current proportion of
total crushed stone consumption and grow at slightly faster rates than the
average. Little or no growth is anticipated in the consumption of traprock
or sandstone, while miscellaneous stone types will continue to decrease in
total tonnage.
Possibilities of Substitution
Limited substitution of alternative products can and does occur depending
on the geographic location of an operation. Sand and gravel, blast furnace
slag, and lightweight aggregates can be used interchangeably with crushed
stone and many specifications accept or even encourage substitutions. An
important criterion considered in making such a decision are the relative
distances of available materials sources from the user. Thus, sand and
gravel pits may prove to be favored as concrete aggregates if the geology
and extraction location shows them to be more economic than stone quarries.
Blast furnace slag, readily available where steel mills are located, can
often be an economic source of aggregate and can also offer distinct
performance advantages when used as an antiskid highway surfacing material.
Lightweight aggregates, such as expanded shale or clay, perlite, or vermicu-
lite can result in considerable reductions in concrete density, and thus
8-13
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building load, when substituted for crushed stone, but the economic
availability of these aggregates is limited.
Marketing and Distribution
Distribution of crushed stone is direct from the quarry to the end
user with no intermediary involved. Inventories are held almost entirely
at the quarry location, as double handling would be prohibitively expensive,
and customers maintain only sufficient inventory to insure uniform produc-
tion rates over a predetermined length of time. Crushed stone production
and shipments is a very seasonal business in many northern regions.
Producers there will typically operate their plants for nine months a year
and stockpile sufficient stone to cover a greatly reduced rate of shipments
in the winter months.
Price Elasticity and Pricing Dynamics
On an industry basis, the demand for crushed stone is price inelastic.
As the product is a necessary component of a number of building materials
(concrete, asphalt) and products (roads, airport runways, etc.), its demand
is based primarily on the demands for these products irrespective of its
price. The fact that there generally does not exist significant competition
from substitute products, and the price of stone as a percentage of the
total price of the materials and products of which it is a component is
low (15% of the FOB price of asphalt—less than ]% of the price of a high-
way for which the asphalt is being supplied, for example), variations in
the price of crushed stone will not affect basic demand.
On a plant-by-plant basis, however, price competition is severe. The
crushed stone business is highly capital-intensive, and producers need to
8-14
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maintain production volume to provide for the amortization of their
capital investments. Thus, while the industry may be tending to an oligopoly
in the local areas where business is transacted, the oligopoly is extremely
competitive in a business sense with regards to price.
8.1.1.3 Gypsum
8.1.1.3.1 General
Anhydrite and selenite usually occur together, but calcined gypsum is a
manufactured product never found in nature. Calcined gypsum is produced by
heating selenite at about 350°F for over an hour. When water is added to
calcined gypsum, plaster of pan's is formed, which quickly sets and hardens
to selenite again. All of these products, including the articles molded from
the plaster, are called gypsum.
8.1.1.3.2 U.S. Plants
In 1973, there were 76 plants calcining gypsum in the U.S. with individual
yearly production falling between 9,070 - 453,500 Mg (10,000 - 500,000 tons) per
year.
In the United States, production of crude gypsum is centered around
three general areas, the Great Lakes area, Texas-Oklahoma, and California.
Leading States were Michigan, California, Texas, Iowa, and Oklahoma. These
five States accounted for 60 percent of the total output.
8-15
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8.1.1.3.3 U.S. Companies
The domestic gypsum industry is a large, well-integrated industry, in
which a few large companies are prominent. These companies mine and sell
crude gypsum for use in cement or agriculture. They mine and import crude
gypsum, calcine it, and market gypsum products. Leading mining companies were
U.S. Gypsum Co. (13 mines), National Gypsum Company (8 mines), Georgia-Pacific
Corporation (7 mines), the Flintkote Company (3 mines), and H. M. Holloway, Inc.
(1 mine). These five companies accounted for 73 percent of tlje total output
of crude gypsum. Thirty-four smaller companies operated 37 mines.
8.1.1.3.4 U.S. Production, Consumption, Prices
Salient industry statistics are presented in Table 8-3.
1972 -
Production: Crude
11
181
(12,328)
Calcined
Imports: Crude, including anhydrite
IU,OHO
(12,005)
7,
(7,
Exports: Crude, crushed or calcined
Consumption: Crude, apparent
Value:
Stocks
Average crude (f.o.b.
mine) $/Mg (per ton)
Average calcine (f.o.b.
plant) $/Mg (per ton)
Producer, crude, yearend e/
18,
(19,
$4
($3
$18
($16
3,
000
718)
46
(51)
135
995)
.33
.93)
.00
.32)
909
(4,310)
Employment: Mine and calcining plant
1973
12
(13
11
(12
6
(7
19
(21
,297 -
,558) ~
,420
,592)
,948
,
,
,
$4
($4
$17
($16
3
(4
4,200 4
,
,
,
661)
57
(63)
188
156)
.61
.18)
.98
.31)
628
000)
500
1974
10,883
(11,999)
9,
(10,
6,
(7,
970
993)
733
424)
119
8
(9
8
(9
4
(5
(132)
17,
(19,
$4
($4
$20
($18
2,
(3,
496
291)
.86
•41)
.63
.71)
721
000)
4,800
13
(15
1975
,844
1976e/
n
in. din '
,751) (11,500);
,327
,181)
,941
,448)
68
(75)
,717
9,432
(10,400).
6,049
(6,670)
68
(75)
lfi.384
,124) {18,095)
$5.05
($4.58)
$5.29
($4.80)
$22.40 $23.47
($20.31) ($21.28)
1
(2
5
,814 '
,000)
,000
1,360
(1,500)
5,100
Source: Commodity Data Summaries Annual, 1977) U.S. Bureau of Mines.
8-16
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End-Uses - Crude gypsum is marketed for use in cement, agriculture,
or fillers. In portland cement, gypsum is universally used to retard
the setting of the concrete. In agriculture, gypsum is used to neutralize
alkaline soils and to provide sulfur.
Calcined gypsum is marketed as plaster or prefabricated products.
Building plaster is generally reground, and retarder and binders are added.
Retarder is usually a glue-type material made from meatpacking-plant
by-products.
The U.S. is the leading world producer and consumer of gypsum with 18
percent of production and 28 percent of consumption. The United States is a
net importer of gypsum.
Gypsum is a low-cost, high tonnage commodity that must compete with many
other building materials. Large mines and integrated plants have helped
producers remain competitive.
8.1.1.4 Diatomite
8.1.1.4.1 General
Diatomite in its natural state is a soft rocklike material consisting
mainly of an accumulation of siliceous frustules (shells) or skeletons of
diatoms that are microscopic single-celled plants of freshwater and saltwater
origin. Chemically, diatomite is essentially amorphous hydrated or opaline
silica with varying amounts of contaminants such as silica sand, clay minerals,
metal salts, and organic matter.
8.1.1.4.2 U.S. Companies/Plants
The United States is the world's largest producer and consumer of
diatomite. In 1976, 9 companies actively mined and prepared diatomite from
16 operations in 5 states—California, Kansas, Nevada, Oregon, and Washington.
8-17
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The major firms have other mineral and manufacturing interests such as the
production of asbestos products, roofing, floor tile, acoustic insulation,
refractories, lead and zinc, plastics, thermal insulation, chemicals, and
industrial fillers.
Employment in the diatomite mining and processing sectors of the industry
is estimated to be about 900 employees.
8.1.1.4.3 U.S. Production, Consumption, and Prices
Salient industry statistics for the diatomite industry are presented in
Table 8-4:
Table 8-4. U.S. DIATOMITE INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
Production: Mine
Imports, general
Exports '
Apparent consumption
Price $/Mg (average per short
ton)
Stocks, yearend e/
Employment: Mine and plant e/
1972
522
(576)
(]/)*
134
(148)
390
f n "D r\ \
(430)
$71.90
(65.19)
34
(38)
800
1973
552
(609)
(I/)
161
(178)
392
(433)
$65.36
($59.26)
32
(36)
850
1974
602
(664)
(4)
3
168
(186)
437
(482)
$84.16
($76.31)
32
(36)
875
1975
519
(573)
(4)
3
133
(147)
390
(430)
$88.25
($80.01)
32
(36)
900
1976 e;
^F,1
JO O
(621)
(5)
4
140
I TU
(155)
427
(471)
$97.83
($88.70)
32
(36)
900
*Less than 100 rug
Source: Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines.
The United States is the largest producer and exporter of diatomite.
Exports have risen very gradually from 116,096 Mg (128,000 short tons) in
1964 to 168,702 Mg (186,000 tons) in 1974.
8-18
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The principal diatomite-producing countries are also the major exporters
of diatomite products. Diatomite is used in nearly every country primarily
for filtration purposes.
Domestic use for diatomite as a filter medium comprised 53 percent of
the 433,546 Mg (478,000 tons) consumed in 1974.
The quantity of processed diatomite used as a filler or extender in the
preparation of various industrial chemicals and paints in the United States
in 1974 was 99,770 Mg (110,000 tons), 23 percent of total consumption.
Transportation has always been an important cost factor in the price
of diatomite to the ultimate consumer because the product is a high-bulk
commodity, and thus has a high freight rate per ton. The cost of moving
diatomite (bulk shipments) from western producing points to midwestern and
east coast markets, for example, has ranged from $27 to $38/Mg ($25 to $35
per ton). However, because of essential industry applications for diatomite,
transportation costs have not seriously affected supply and demand in the past.
8.1.1.5 Perlite
8.1.1.5.1 General
Perlite, a glassy volcanic rock, has the unusual characteristic of
expanding to about 20 times its original volume when heated to an appropriate
temperature within its softening range. The resultant expanded product finds
a variety of industrial and constructional applications owing to the material's
low density with attendant properties of low thermal conductivity and high
sound absorption.
3-19
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8.1.1.5.2 U.S. Companies/Plants
Domestic production of crude perlite (quantity sold and used) in 1976
was a record 598,620 Mg (660,000 tons) from IT operations in 6 Western States.
Deposits in New Mexico supplied 88 percent of the total crude perlite mined
in 1974. Expanded perlite was produced at 76 plants in 30 States. The
principal States in descending order of expanded perlite output in 1974 were
Illinois, Mississippi, Kentucky, Pennsylvania, Colorado, Florida, New Jersey,
Texas, California, and Indiana.
Employment in perlite mining and milling was estimated to be 121 employees
in 1976. In addition, there were many hundred more employees in the expanding,
product development, basic research, and marketing activities of the industry.
8.1.1.5.3 U.S. Production, Consumption, and Prices
Salient industry statistics for the domestic perlite industry are
:i,*
presented in Table 8-5.
Table 8-g. u.S. PERLITE INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
Salient Statistics-United States: 1972 1973 1974 ^975 1976 e/
Production: Mine 588 688 613 64Q 598
(649) (759) (676) (706) (660)
Imports None of Record
Exp°rtS Not Available
Consumption, reported 494 493 503 m 4g]
(545) (544) (555) (512) (542)
' $/Mg
Stocks, year-end Not A,va1lable
Employment: Mine and mill 100 }QQ nQ ]1Q ^
Source: Commodity Data Summaries Annual. 1977, U.S. Bureau of Mines.
Industrial uses for perlite (expanded) are many and varied. The more
important applications include the following: abrasives, acoustical plaster
and tile, charcoal barbecue base, cleanser base, concrete construction aggregates
8-20
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filter aid, fertilizer extender, foundry ladle covering and sand additive,
inert carrier, insulation board filler, loosefill insulation, molding filler
medium, packaging medium, paint texturizer, pipe insulator, plaster aggregate
and texturizer, propagating cuttings for plants, refractory products, soil
conditioner, tile mortar aggregate and lightweight insulating concrete for
roof-decks, and wall board core filler.
Exfoliated vermiculate is the most directly competitive material with
perlite aggregates in plaster and other insulation applications in the construc-
tion field. Lightweight aggregates such as pumice, expanded clay, shale, and
slag, volcanic cinders, or foamed concrete are used where considerations of
lower cost or greater structural strength more than balance the advantage of
low density achieved by using perlite.
8.1.1.6 Pumi ce
8.1.1.6.1 General
Although domestic use prior to World War II was largely as an abrasive,
the importance of pumiceous materials as low-cost construction aggregate
increased rapidly and has since dominated the U.S. pumice consumption pattern.
8.1.1.6.2 U.S. Plants
Domestic production of pumiceous materials in 1976 was 4.03 million tons
from 235 operations in 12 States (including Hawaii) and American Samoa. The
principal producing States are Arizona, California, and Oregon, and their
combined output accounted for 68 percent of the national total of pumiceous
materials in 1974. Other States with significant output were Hawaii, Nevada,
and New Mexico.
8-21
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Although employment in the pumiceous materials industry varies
considerably from year to year, owing primarily to closing and opening
of volcanic cinder pits when local contracts for road construction material
terminate and start up, it was estimated that about 600 workers were in
mining and processing in 1976.
8.1.1.6.3 U.S. Companies
In 1976 there were 77 pumice producing companies. Producers range from
private individuals to companies to governmental agencies at local, State and
Federal levels. There is also a wide range from small, intermittent, to large
tonnage operations. Most of the producers have mining and processing of
pumiceous materials as their sole or major interest; however, some, such as
railroad companies and road construction contractors, produce the material only
as a subsidiary part of their principal business.
8.1.1.6.4 U.S. Production, Consumption and Price
Industry statistics for the domestic supplier industry is presented in
Table 8-6.
i
Table 8-6. U.S. PUMICE INDUSTRY (in thousand Mg and
thousand short tons 1n parentheses)
15Z2 1973 J974 J975 1976 e/
Production: Mine 3,458 3,570 3,570 3 530 * fiRR
(3,813) (3,937) (3,937) (I'M!) '
Imports for consumption 543 281 265 m
(599) OlO) (293) (J45)
- ,1, (i)
Stocks, year-end Not Ava1lab]e
Employment: Mine and mill 525 545 560 580 600
* less than 1000 Mg.
Source: Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines.
8-22
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The largest domestic use of pumiceous materials is in the construction
industry, which accounted for 92.5 percent or 3 million Mg (3.9 million tons)
of demand in 1974. Construction uses principally include road surfacing,
maintenance, and ice control, concrete admixtures and aggregate, and railroad
ballast. Demand for other uses totaled 263,030 Mg (290,000 tons) in 1974;
the quantity of pumice used only for various abrasive purposes was estimated
to be 22,675 Mg (25,000 tons).
Transportation is an important cost factor in the economics of the domestic
pumice industry. Abrasive grades ($34.00/Mg - $31.00/ton) can be shipped even
from foreign sources and be competitive; but pumice of low market value ($1.13/Mg
to $40/ton) such as that used for construction purposes, is usually limited to a
few hundred miles by rail or truck transportation. Pumice for construction uses
becomes less competitive with alternate choice materials in rough proportion to
the distance that pumice resources are available from the place of consumption.
8.1.1.7 Vermiculite
8.1.1.7.1 General
Vermiculite, a mica-like mineral with the unique property of exfoliating
to a low-density, bulky material when heated, is widely used in the construction
industry. Vermiculite concrete is used for roof decks and floor fill where
lightweight, thermal insulation, and acoustical properties are of particular
importance.
8.1.1.7.2 U.S. Companies/Plants
In 1975, the only domestic producers of crude Vermiculite were the
Construction Products Division, W. R. Grace & Company, which operates a large
mine near Libby, Montana, and a group of smaller mines near Enoree, South
Carolina, and Patterson Vermiculite Company, Enoree, South Carolina.
8-23
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Exfoliated vermiculite was produced at 53 plants in 31 States in 1974.
Five States supplied 46 percent of the total: California, Florida, New
Jersey, South Carolina, and Texas. W. R. Grace & Company, the leading
producer of crude vermiculite, operated 28 exfoliating plants. Patterson
Vermiculite Company used all its production of crude vermiculite at its
Enoree, South Carolina exfoliating plant. Twenty-two other firms operated
25 exfoliating plants. W. R. Grace & Company had a financial interest in
several of these firms, but most of them were independent processors. Total
production of crude and exfoliated vermiculite in 1974 was 309,287 and
249,425 Mg (341,000 and 275,000 short tons), respectively.
Most exfoliating plants are small, and over half produce less than
4535 Mg (5,000 tons) each of expanded vermiculite annually. About 250 workers
were employed at vermiculite mines and mills in 1973. Several hundred
additional employees operated vermiculite exfoliating plants.
8.1.1.7.3 U.S. Production, Consumption, and Prices
Industry statistics for vermiculite are presented in the following table.
Table g^;, U.S. VERMICULITE INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
Salient Statistics—United States: 1972 1973 1974 197_5 1976
Production: Mine
Imports: Crude
Exports:
Consumption: Exfoliated
Prices: Average $/Mg (per ton), \
f.o.b. mine $26.48 $28.60 $32.73 $46.06 $46.32
($24.01) ($25.93) ($29.68) ($41.76) ($42.00)
Producer stocks, year end NotAvailable
Employment: Mine and mill -225 250 250 250 250
Source: Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines.
8-24
305
(337)
23
(26)
NA
224
(247)
331
(365)
27
(30)
NA
265
(293)
| 309
(341)
38
(42)
NA
249
(275)
299
(330)
29
(33)
38
(42)
213
(235)
272
(300)
27
(30)
40
(45)
204
(225)
-------
Railroad freight rates are high, and shipping costs for crude vermiculite
sometimes exceed the mine value. The rail-freight rate for shipping vermiculite
from Montana to the Atlantic and Gulf coasts is comparable with the transportation
cost from South Africa. This makes it economic for some South African crude
to enter the country. Some of this vermiculite is transshipped by rail or
barge to inland points.
8.1.1.8 Mica
8.1.1.8.1 General
Mica is a group name for a number of complex, hydrous potassium silicate
minerals with differing chemical composition and physical properties. Crystals
of mica have characteristic excellent basal cleavage and split easily into
tough, flexible sheets. Principal minerals of this group are muscovite
(potassium mica), phlogopite (magnesium mica), biotite (magnesium iron mica)
and lepidolite (lithium mica). Muscovite and phlogopite are the most important
commercial micas.
8.1.1.8 .2 U.S. Companies/Plants
In 1974, block and film mica was produced by 13 companies in 7 States.
New Jersey with four consuming plants, New York with three, North Carolina
with two, and Pennsylvania with one produced 75 percent of the domestically
fabricated block and film. Other States with block and film fabricators are
Massachusetts, Ohio, and Virginia.
Splittings were fabricated into various built-up mica products by 11 com-
panies with 12 plants in eight States. Plants in New Hampshire, New York,
and Ohio consumed 80 percent of the splittings. Other States with plants
consuming mica splittings were Michigan, Massachusetts, North Carolina and
Virginia.
8-25
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North Carolina was the largest scrap and flake producing State with 56
percent of total production in 1974. The remaining output of scrap and flake
mica came from Alabama, Arizona, Connecticut, Georgia, New Mexico, South
Carolina, and South Dakota.
Ground mica was produced by 16 companies with 18 plants in the following
10 States: Alabama, Arizona, Georgia, Illinois, New Hampshire, New Mexico,
North Carolina, Pennsylvania, South Carolina, and Texas.
8.1.1. 8.3 U.S. Production, Consumption and Prices
Salient statistics for the U.S. mica industry are presented in the
following table.
Table 8-8 u-s- HICA INDUSTRY (In thousand Hg and
thousand short tons 1n parentheses)
1972 1973 1974 1975 1976
Production: Mine 134 138 124 122 119
(148) (153) (137) (135) (132)
Imports for consumption ,,, ,r, ,f, ,;,
(3) (3) (f>) (b)
F«nnrts »/ 44444
EXP°rtS5/ (5) (5) (5) (5) (5)
Consumption 117 124 106 102 104
(130) (137) (117) (113) (115)
Price per Mg (avg, per ton):
Scrap & flake $30.01 $30.01 $37.89 $42.64 $44.12
(27.21) ($27.21) ($34.36) ($38.66) ($40.00)
Ground (current year) Dry: $44-110 ($40-100/ton) Wet: $242-397 ($220-360/ton)
Stocks: Consumer, yearend e/ <«, {f°, *} «, («
Employ^: Mine,/ «} »} fa fa fa
Source: Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines.
Demand for ground mica is linked primarily to the building Jndustry; how-,
ever, 1973 was a record high year for both ground and scrap and flake mica. The
production of ground and scrap and flake mica was significantly lower for 1974 and
1975 because of problems in the building industries.
8-26
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In 1974, ground mica for use in gypsum wallboard cement required
37,187 Mg (41,000 short tons), followed by paint with 30,838 Mg (34,000
short tons), roofing materials with 9,070 Mg (10,000 short tons), and the
rubber industry with 6,349 Mg (7,000 short tons).
Many substitutes are available for ground mica when it is used as a
filler. Ground synthetic fluorophlogopite has been successfully used to
replace natural ground mica for uses that require the thermal properties of
the mica.
8.1.1.9 Natural Rock Asphalt
8.1.1.9.1 General
According to Mr. E. G. Williams, an Asphalt Institute Engineer stationed
in Louisville, Kentucky, at present there is no production of natural rock
asphalt in the United States. Production ceased about 1965 due to the
exorbitant cost of the natural product compared to asphalt produced by
petroleum cracking processes. There are no known plans to resume production
of natural rock asphalt.
The scant mine company information available with regard to those most
recently engaged in natural rock asphalt processing, all non-operational, are
listed below.
Kentucky: (Sandstone impregnated)
Gripstop Corporation
Subsidiary of Reynolds Aluminum
Alabama: Very small, local operation
(limestone impregnated)
Texas: Mine located in Valdez, Texas
8-27
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The American Gilsonite Company in Utah is the only domestic producer
of metamorphosized asphalt called gilsom'te. Production is less than 90,700
Mg (1005000 tons) per year used primarily for specialty products. Less than
9.070 Mg (10,000 tons) per year is consumed east of the Mississippi River.
E.G. Williams
Asphalt Institute Engineer
4050 Westport Road
Louisville, Kentucky 40207
(502) 895-6966
8.1.2 NON-METALLIC MINERALS FOR THE CHEMICAL AND FERTILIZER INDUSTRIES
8.1.2.1 Barite
8.1.2.1.1 General
Barite (BaSO*) is the only source of barium and barium compounds. The term
"primary barite," as used in this report, refers to the first marketable product
and includes crude barite, flotation concentrate, and other beneficiated material
such as washer, jig, or magnetic separation concentrate. Most primary barite
requires fine grinding before it is used for drilling muds. This grinding may
or may not be done at the mine site.
8.1.2.1.2 U.S. Plants/Companies
Domestic production of barium in 1976 was from 31 mines in 9 States.
Nevada supplied 69 percent of the tonnage. Missouri produced 16 percent.
Alaska, Arkansas, California, Georgia, Idaho, Illinois, and Tennessee were
other producing States.
Companies which specialize in the drilling mud business also have foreign
mines and import part of their barite supplies. They have grinding plants
strategically located throughout the world to serve drilling mud markets.
8-28
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They provide a variety of drilling mud minerals, chemicals, and services
to the oil and gas industry.
Ground and crushed barite was produced in 1974 mainly in Louisiana and
Texas from domestic and imported material and in Arkansas, Missouri, and
Nevada from domestic barite. Processing mills were also located in
California, Georgia, Illinois, Tennessee, and Utah.
Domestic mining, milling, and grinding of barite to a marketable product
required about 1200 employees in 1976. Most barite plants process from
9-45 Mg (10-50 tons) per hour.
8.1.2.1.3 U.S. Production, Consumption and Prices
Salient statistics for the U.S. barite industry are presented in the
following table.
Table 8"9 U.S. BARITE INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
1972 1973 1974 1975 1976 e/
Production: Nine I/ UO^ U* (l.lg) UO*
565 649 661 575 680
Imports for consumption /624) /716\ (72g) (534) (750)
(crude barite)
47 61 55 51 42
Exports (ground and crushed) JKJ j68j (61) (57) (47)
Reported consumption
Und and crushed) K3* (1.4« U5W ^ (1 .^
$18.12 $16.67 $16.77 $17.71 $23.21
Price: $/Mg (per ton) : ($16.43) ($15.12) ($15.21) ($16.06) ($21.05)
f.o'.b. mine (avg. ) >T
Producer stocks, yearend Not Available
Employment: Mine and mill e/ 1.025 1,100 1,200 1,200 1,200
Source: Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines.
The United States is a net barite importer. Imports of barium in 1974
amounted to 40% of the total supply. Barium imports have remained near this
percentage for the twenty-year trend.
The major use for barium is in the form of barite as a weighting material
in well-drilling muds, accounting for 87 percent of the 1974 U.S. consumption.
8-29
-------
Barite is also a raw material of chemical manufacturing. The major
barium chemicals are the carbonate, chloride, oxide, hydroxide, nitrate,
peroxide, and sulfate. The barium compounds represent 6 percent of total
barium consumption.
A number of materials have been substituted for barite as a weighting
medium in drilling muds in the past but never with a real competitive edge.
8.1.2.2 Fluorspar (Fluorine)
8.1.2.2.1 General
Fluorine, derived from the mineral fluorite, commonly known as fluorspar, is
one of the most versatile and useful of the elements. Steadily increasing
quantities are required in steel production, where the mineral 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. Strong as the fluorine
demand has been in the foregoing uses, it has been even stronger for an
important group of fluorocarbon chemicals which are formulated into refrigerants,
plastics, solvents, aerosols, lubricants, coolants, surfactants, rocket fuels,
medicinals, aluminum fluoride, and many other industrial products.
8.1.2.2.2 U.S. Plants/Companies
At the start of 1973, there were 23 mines and 7 froth flotation plants
in operation; during the year 8 mines and 4 flotation plants closed down.
Cumulatively over 126,980 Mg (140,000 tons) of flotation milling capacity was
lost; but during the past 2 years the output from these plants has only averaged
about 81,630 Mg (90,000 tons) annually, mainly because the mines could not supply
the mills. In 1975, 10 companies operated 15 mines in the United States.
8-30
-------
Although some domestic fluorspar is sold with little or no processing
after mining, most crude ore requires beneficiation or yield a finished
product.
Manpower required by the U.S. fluorspar industry is not large. An
estimated 350 men are employed in mines and 250 in mills.
8.1.2.2.3. U.S. Production, Consumption, and Prices
Salient statistics for the U.S. fluorspar industry are presented in
the following table. (Data in 1000 Mg; 1000 short tons in parentheses.)
Table 8-10. *-s FLUORSPAR INDUSTRY (1n thousand Mg and thousand
short tons 1n parentheses)
1972 1973 1971 1975 1976^
Production: Finished (all grades)^/ 227 225 162 126 163
(251) (225) (182) (140) (180)
Fluorspar equivalent from phosphate rock 58 76 87 72 72
(65) (84) (97) (80) (80)
Imports for consumption:
Acid-spar 644 640 764 633 535
(711) (706) *843) (699) (590)
Met-spar 427 458 447 • 318 281
(471) (506) (493) (351) (310)
Exports: Ceramic and add grades 2 1 5
(3) (2) (6) (1) (1)
Sales of Gov't stockpile excesses
Apparent consumption 1349 1368 1296 1179 1060
(1488) (1509) (1429) (1300) (1169)
Reported consumption: Acid-spar 663 614 762 619 498
(731) (677) (841) (683) (550)
Met-spar 563 612 620 509 589
,. (621) (675) (684) (562) (650)
Priced Acid-spar, $/Mg (per ton) $93 $93 $99 $106 $116
($85) ($85) ($99) ($97) ($106)
Met-spar. $/Mg (per ton) $75 $71 $77 $88 $95
($68) ($65) ($70) ($80) ($87)
Year-end stocks: Mine 13 8 12 9 10
(15) (9) (14) (11) (12)
Consumer • 342 297 390 290 263
(378) (328) (431) (320) (290)
Employment: Mlne^, 600 600 350 300 300
Mill5' 270 280 100 193 200
"I Source: Commodity Data Summaries Annual, 1977, U.S. Sureau of Mines
Shipments
Consumption of fluorine is chiefly in the chemical, steel, and aluminum
industries. An estimated 622,202 Mg (686,000 tons) was consumed by U.S.
industries in 1974. Mnay marginal U.S. mines have been forced to close
owing to low-cost imports of fluorspar, contributing to greater dependence
on foreign supply. A gradual upward trend in the price of foreign fluorine
imports may result from increasing world demand and stimulate development
of more reserves. Both domestic and foreign producers have instituted
programs for increasing output by reopening and refurbishing existing mines
and exploring for new deposits.
8-31
-------
U.S. dependence on foreign supplies for most of its fluorine demand
has existed since 1952 and is increasing. Lower foreign production cost
rather than inadequate domestic deposits of fluorine minerals is the chief
reason for the U.S. increasing dependence on foreign sources of supply.
8.1.2.3 Salt (NaCI)
8.1.2.3.1 General
Salt is an essential nutrient in the human diet and a major basic raw
material for production of various chemicals and products. In 1974, about
one-third of the world's salt was produced in Europe; another third in North
America; and one-fifth in Asia. Vast salt reserves throughout the U.S. are
concentrated in 16 states and estimated at 61 trillion tons.
8.1.2.3.2 U.S. Plants
In the United States there are 97 plants processing salt from 106 mines
(1974). Most of these plants are concentrated in eight states which accounted
for 96% of the total production of 1973. Louisiana and Texas are the major
producer/processor states with 29.1 and 24.4 percent respectively of total 1974
U.S. production. U.S. employment in salt processing operations for 1976 was
estimated to be 5,040.
8.1.2.3.3 Companies
There are 52 salt processing companies in the United States. In 1974,
twelve companies each produced more than 1 million tons of salt accounting for
88% of total U.S. production. Eighteen companies individually producing
between 90,700 - 907,000 Mg (100,000 and 1 million tons) added 11% to the
total with the remaining 1% produced by 22 companies with a yearly output of
less than 90,700 Mg (100,000 tons) each.
8-32
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Most large salt companies are vertically integrated starting with salt
produced as brine, for example, being consumed on the site for making
chlorine and caustic soda or soda ash.
8.1.2.3.4 U.S. Production, Consumption and Process
Salient statistics for the U.S. salt industry are presented in the
following table.
Table 8-11. U-S. SALT INDUSTRY (1n thousand Mg and
thousand short tons in parentheses)
1972 1973 1974 1975 1976
Sold or used by producers 2/ 40,834 39,826 42,208 37,214 38 127
(45,022) (43,910) (46,536) (41,030) (42,037)
Imports for consumption 3-14° ,2'908. ,3.°« 2,916 3,741
(3,463) (3,207) (3,358) (3,215) (4,125)
Exports 788 552 172 1,208 946
(869) (609) (521) (1,332) (1,044)
Apparent consumption 43,187 42,182 44,781 38 922 40 922
(47,616) (46,508) (49,373) (42,913) (45,118)
Prices: Rock salt, medium
course in 100 Ib. $21.39 $21.39 $21.39 $2978 $2978
bags quoted dollars ($19.40) 1($19.40) ($19.40) (27.00) (27.00)
$/Mg (per ton)
Average sales price
f.o.b. mine, dry $11.71 $12.97 $14.12 $15.91 $18 29
(including bulk & ($10.62) ($11.76) ($12.81) ($14.43) ($16.59)
pressed but exclud-
ing bnine), $/Mg
(per ton)
Stocks, yearend NA NA 4,700 2,400 2,400
Employment: Mine and Plant 5,070 4,950 5,280 4,920 5,040
Source: Commodity Data Summaries Annual, 1977. U.S. Bureau of Mines.
Percentage breakdowns for 1976 production end-uses roughly are: caustic
soda and chlorine - 60%; synthetic soda ash - 11%; miscellaneous chemicals -
3%; highway deicing - 18%; salt for human consumption - 3%; and all other uses - II
Because of its relatively low production cost and high bulk density, the
cost of shipping salt is usually a large part of its cost as used. Such
commodities are poorly suited to international trade. The 6.8% U.S. 1974 salt
import was mainly from bordering Canada and Mexico.
8-33
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8.1.2.4 Boron
8.1.2.4.1 General
Boron is a versatile and useful element used mainly in the form of its
many compounds, of which borax and boric acid are most well known. The
largest single use of boron is in glassmaking where boron compounds add
strength to the glass, especially above the temperatures of which ordinary
glass softens.
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
commercially attractive world boron resources, estimated at about 72 million
tons of boron, are in southern California.
8.1.2.4.2 U.S. Plants/Companies
Three companies produced borax in the United States during 1975, all
operating in southern California. U.S. Borax & Chemical Corp., by far the most
important producer, mined borax (or tinea!) and kernite at a large open pit
mine at Boron. U.S. Borax also owns and operates refineries and products plants
at Boron in Kern County, at Wilmington in Los Angeles County, California, and at
Burlington, Iowa.
Overall, nearly 2,000 persons are employed within the U.S. boron extraction
industry. There is no secondary recovery and ,reuse of boron compounds, since
almost all of this goes into dissipative uses.
8-1.2.4.3 U.S. Production, Consumption and Prices
Salient statistics for the U.S. boron industry are presented in the
following table.
8-34
-------
Table 8-12 u.s. BORON INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
1972 1973 1974 1975 1976
Production (boron minerals and 1,016 /I,111 1,074 1,063 1,088
compounds) (1,121) (1,225) (1,185) (1,172) (1,200)
Imports (boron minerals and 18 16 19 25 27
compounds (20) (18) (21) (28) (30)
Exports (boric acid and 172 190 230 223 235
refined borates) (190) (210) (254) (246) (260)
Apparent consumption NA NA 103 88 95
(contained boron) (114) (93) (105)
Price: $/Mg (per ton)(granu-
lated pentahydrate $82 $88 $88 $110 $115
borax in bulk, f.o.b. ($75) ($80) ($80) ($100) ($105)
mine)
Stocks, yearend Not Available
Employment]/ 1,800 1,800 1,800 1,800 1,900
Source: Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines.
Two-fifths or more of the boron compounds consumed were used in the manu-
facture of various kinds of glasses within the United States. Boron materials
account for 5 to 10 percent of many special glasses by weight and 50 to 75
percent by value. About 15 percent of all boron consumed went into insulating
fiberglass, 10 percent into textile fiberglass, and 15 to 20 percent into all
other glasses. The energy shortage has created a further demand for insulating
fiberglass.
Between year-end 1973 and November 1974, the price of anhydrous borax
(bulk) rose from 121/Mg ($110 per short ton) to $223/Mg ($203) for U.S. Borax,
and the price of boric acid increased from $147 to 219/Mg ($134 to $199). These
increases reflect steep rises in energy cost, inflation, and strong demand.
The sharper rise in costs of anhydrous products, compared with costs of products
with water, can be explained by the more intense use of energy in fusion than in
distillation and chemical processing.
8-35
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8.1.2.5 Potash (KgO)
8.1.2.5.1 General
Potash is the common term for compounds of the element potassium, and it
is frequently used to mean the potassium oxide, K20, content of substances,
even though no oxide is actually present. For example, the chief compound
potassium found in potash ores is the chloride, KC1, and concentrates are
generally sold on the basis of equivalent K20 content (about 60 percent).
Statistics on potash in this description mean short tons of K20.
8.1.2.5.2 U.S. Plants/Companies
The U.S. potash industry now comprises 10 firms, which operate 11 facili-
ties; 7 underground mines in New Mexico, 1 underground solution mine in Utah,
2 brine treatment plants in Utah, and 1 brine treatment plant in California.
The potash producers are all subsidiaries or divisions of large diversified
U.S. owned minerals producers.
It is estimated that about 4,200 persons are employed in mining and pro-
cessing potash minerals in the United States. The bulk of these are employed
in the vicinity of Carlsbad, New Mexico and this employment constitutes a
major source of income there.
The estimated annual capacity in tons of IG>0 for individual U.S. plants
ranges from 34,420 to 498,850 Mg (60,000 to 550,000 tons) per year.
8.1.2.5.3 U.S. Production. Consumption and Prices
Salient statistics for the U.S. potash industry are presented in the
following table.
8-36
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Table 8-13. u.s. POTASH INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
1972 1973 1974 1975 1976
2,411 2,360 2,314 2,268 2,167
Production: Marketable (2,659) (2,603) (2,552) (2,501) (2,390)
..ports for cons.pt,.n (|.W «» (3.» (3.3.
692 806 713 697 808
Exports (764) (889) (737) (769) (891)
4,367 5,051 5,518 4,590 5,767
Apparent consumption (4,815) (5,570) j(6,084) (5,061) (6,359)
Price: Cents per short ton
unit of K?0, standard 60% . . .
muriate fTo.b. Carlsbad (34) (38) (49) (73) (72)
(average, quoted)
-Stocks, producer, yearend ' ..... ^ (186) (191} (561g) (4g)
Bnplojnent: Jine 1.183 1.100 1.100 1,500 1,500
Source: Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines.
About 95 percent of U.S. potash consumption is for fertilizer. It is
an essential plant nutrient, for which no alternative exists. Potash must be
supplied to the soil in increasing quantities if U.S. farms are to produce
the food for growing world population needs.
Potash from U.S. mines supplied all the Nation's needs until 1962, but
production has remained almost static for over a decade; recent growth in
U.S. demand has been met from foreign sources. In 1974, domestic production
of 2.31 million Mg (2.55 million tons) of K20 was equal to only 42 percent of
demand. 1976 production was estimated to be 2.17 million Mg (2.4 million
short tons).
The United States is not self-sufficient in potash production, but from
a strategic standpoint, Canadian potash mines are fortunately close to U.S.
borders, and transportation should present no problem, even in an emergency.
The supply from Saskatchewan is adequate.
8-37
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8.1.2.6 Sodium Compounds
8.1.2.6.1 General
The compounds of sodium are of primary importance to the whole chemical
manufacturing industry. Although not always present in the finished product,
sodium plays some part in the preparation of nearly every product requiring
chemical processing.
Soda ash is the term used in the industry for sodium carbonate.
Solvay soda or ammonia soda are terms used interchangeably for sodium
carbonate produced from salt by the Solvay process.
Salt cake is the term used for sodium sulfate. Glauber salt is a common
hydrated form of sodium sulfate.
8.1.2.6.2 U;S. Plants
In 1975 there were nine soda ash plants, 4-synthetic and 5-natural, in the
United States, located in New York, Michigan, Ohio, Texas, Wyoming and California,
Sodium sulfate was produced at 28 plants in 15 states.
There were only four Solvay plants left in the United States in 1975
after the permanent closing of two major producers in Louisiana. High cost
of fuel and other raw materials, combined with strict antipollution laws, have
made it difficult for Solvay soda ash to compete with natural soda ash.
Most of the world's supply of natural soda ash comes from a small area in
southwest Wyoming called the Freen River Basin. A secondary source of natural
U.S. soda ash is in Searles Lake, California.
Natural sodium sulfate is extracted from brines of California, Texas, and
Utah. About three-fourths of the by-product sodium sulfate plants are located
east of the Mississippi River.
8-38
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About 2,800 people are employed in the natural soda ash industry and
an additional 130 in producing natural sodium sulfate.
8.1.2.6.3 U.S. Companies
There were eight soda ash companies in 1975; 4-synthetic and 4-natural;
and three natural sodium sulfate companies. By-product sodium sulfate was
produced by 18 companies in 15 states.
U.S. soda ash companies are: Kerr-McGee Chem. Corp., Stauffer Chemical
Corp., Allied Chemical Corp., and FMC Corp.
U.S. sodium sulfate companies are: Stauffer Chemcial Co., Kerr-McGee
Chem. Corp., U.S. Borax & Chem. Corp., Ozark-Mahoning Co., and Great Salt
Lake Minerals and Chem. Corp.
8.1.2.6.4 U.S. Production, Consumption and Prices
Salient statistics for the U.S. sodium carbonate industry are presented in
the following table.
fi Id • U-S- S0DIUM CARBONATE INDUSTRY (in thousand Mg and
o-it. thousand short tons in parentheses)
19Z1 J973 1974
1976 e/
Production: Natural 2,918 3)375
(3,218) (3,722) (4,059) (^ll) (5J8?
Manufactured (solvay) 3,904 3,458 3,180 2,541 2,193
(4,305) (3,813) (3,507) (2,802) (2,418)
Imports for consumption -- 14 31 2 1
(16) (35) (3)
Exports (mostly refined) 435 385 511 500 527
(480) (425) (564) (552) (582)
Producer stocks at yearend, 83 95 71 1KI-
natural rq?l nn^ ,, , ,165 72
(92) (105) (79) (182) (80)
Employment: Mine and plant l >070 1,330 2,651 2,765 2,905
Source: Commodity Data Sundries Annual, 1977,
Qf
8-39
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635
(701)
567
(626)
271
(299)
26
(29)
609
(672)
694
(766)
290
(320)
40
(45)
620
(684)
602
(664)
340
(375)
46
(51)
604
(667)
507
(560)
258
(285)
69
(77)
594
(656)
548
(605)
314
(347)
44
(49)
Salient statistics for the U.S. sodium sulfate industry are presented in
the following table.
Table 8-15. u.s. SODIUM SULFATE INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
1972 1973 1974 1975 1976
Production: Natural
By-product
Imports for consumption
Exports
Apparent cons-mption (natural 1,449 1,553 1,516 1,301 1,414
and by-product) (1,598) (1,713) (1,672) (1,435) (1,559)
"Price: Quoted (salt cake -
100 % Na2S04, in
carlots bulk at works, $30 $30 $34 $66 $71
$/Mg (per ton) ($28) ($28) ($31) ($60) ($65)
Average sales price
(natural source), f.o.b.
mine or plant, $/Mg $17.93 $19.03 $26.46 $45.75 ($54.85
(per ton) ($16.26) ($17.26) ($23.99) ($41.48) ($49.73)
Producer stocks at year- 80 80 29 30 34
end, natural (89) (89) (32) (34) (38)
Employment: Wells & Plant 105 132 126 130 135
Source: Cotunodlty Data Summaries Annual, 1977, U.S. Bureau of Mines.
The manufacture of glass absorbs from 39 to 49 percent of the soda ash
production and about 7 percent of the sodium sulfate output. The pulp and
paper industry consumes about 70 percent of the sodium sulfate output and about
9 percent of the soda ash supply. The production of detergents also require
both compounds: about 20 percent of the sodium sulfate supply and 4 to 6 percent
of the soda ash production. In addition, 23 to 25 percent of the soda ash supply
is used in producing other chemicals, and about 3 percent is used in water treat-
ment. Miscellaneous uses absorb the remaining soda ash output and 3 percent of
the sodium sulfate production.
8-40
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Reserves of natural sodium sulfate in the United States are limited,
and present requirements are met by imported material. If there is no
interruption in flow of sodium sulfate from Canada, however, there is little
likelihood of a real shortage of salt cake.
8.1.2.7 Pyrites
8.1.2.7.1 General
Pyrites are mined for sulfur content. The contained sulfur in pyrites,
hydrogen sulfide and sulfur dioxide accounted for 3% of all domestic production
in all forms during 1974. The sulfur content of the pyrites production amounted
to 146,934 Mg (162,000 tons) or .01 of 1974 total sulfur production. Pyrites
were produced by three companies at three mines in three States. They were:
1. Cities Service Corporation
(Coppermine)
Copperhill, Tennessee
2. Climax Molybdenum Corporation
Climax, Colorado
3. Magma Copper Corporation
Superior, Arizona
Pyrites were mined and processed at locations 1 and 3 in conjunction
with copper mining, and after conversion to H2S04 at the plant, used at the
mine site for copper leaching.
Pyritic ores of 40- to 50-percent sulfur content are generally roasted for
the production of sulfur dioxide gas as a feed to an associated sulfuric acid
plant. The iron cinder from the roasting operation is often leached to recover
nonferrous metals and sometimes sold as iron ore. This well-developed and widely
8-41
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used process is of major importance in countries of the world that do not
have access to cheap sources of elemental sulfur or that contain pyritic
deposits into which the co-product mineral and cinder values are of
importance.
Sulfur recovery from pyritic ores is not an integral sulfur production
process in the United States.
Import, export, price, and growth data were not available. An estimated
value of $13.00/Mg ($12.69 per short ton) for 1975 was assigned to pyritic
ores by the physical scientist researching sulfur at the Bureau of Mines.
8.1.3 NON-METALLIC MINERALS FOR CERAMIC, REFRACTORY AND MISCELLANEOUS INDUSTRIES
8.1.3.1 Clays
8.1.3.1.1. General
Clays are a group of important fine-grained non-metallic minerals which
are mostly hydrous aluminum silicates containing various amounts of organic
and inorganic impurities.
8.1.3.1.2 U.S. Plants/Companies
Most clays are mined by open pit methods, but in a few instances underground
methods are used. About 2 percent of the U.S. total clay output is from
underground mines.
Kaolin has many industrial applications, and many grades are specifically
designed for use in paper, paints, rubber, plastics and ceramics.
Most of the large kaolin producers have principal operations in Georgia.
In 1975 three large diversified firms accounted for about 36% of the total
domestic output, and four refractories manufacturers mined 10 percent of the
U.S. total for their own use. A total of 35 smaller companies accounted for
the balance. Altogether 52 firms operated 120 mines in 14 States.
8-42
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Ball clay is used primarily in production of whiteware because of its
extremely refractory nature. The ball clay industry is small, with 11 pro-
ducers operating 52 mines in 8 States in 1975. Two of these were large
diversified firms with widespread foreign and domestic mineral interests.
Fire clay producers were mostly refractories manufacturers that used the
clays in firebrick and other refractories. A large part of the fire clay was
mined and used by producers of structural clay products.
In 1975 there were 7 firms producing bentonite from 498 mines in 13
States. Four were large diversified firms with international mineral operations;
two of the firms had interests in other types of clay in the United States.
Seven of the 17 fuller's earth producers and 11 of the mines were located
in the attapulgite fuller's earth areas of Florida and Georgia. Production,
mostly small scale, was reported from seven other States in 1975. Most
producers were small independent firms, but four were large diversified cor-
porations with international mineral interests.
Firms producing miscellaneous clay in 1975 were manufacturers of structural
clay products, clay pipe, lightweight aggregates, and cement. Essentially all were
integrated to the extent of owning and operating the deposits of clay used in
making their products. A few of the miscellaneous clay producers were diver-
sified firms having interest in metals and other non-clay products. Some of the
miscellaneous clay producers had numerous plants. This is necessary if they
are to be major firms, because the economic shipping radius for the individual
plants is usually about 200 miles.
Most clay industry plants produce 3-136 Mg (4-150 tons) per hour of product.
8-43
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Employment in the clay industries totaled 16,000 in 1975. Approxi-
mately one-fourth of the workers were involved in mining and exploration,
and the balance were engaged in processing the clays for various end uses.
Although employment was widespread, certain areas had disproportionately
large percentages of the clay workers. An estimated 80 percent of the
kaolin employment was in Georgia, and over 90 percent of the fuller's earth
workers were in Florida and Georgia. Ohio, Missouri, and Pennsylvania
accounted for over 50 percent of the fire clay employment.
8.1.3.1.3 U.S. Production, Consumption, and Price
Salient statistics for the U.S. clay industry are presented in the
following table. (Data in 1000 Mg; 1,000 short tons in parentheses.)
Table 8-16. u.s. CLAY INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
lEZi 1973 1974 1975 1976
Mine production:
Kaolin 4'823 5,435 5,798 4,837 5,188
(5,318) (5,933) (6,393) (5,334) (5,720)
Ball clay 612 695 741 640 782
(675) (767) (817) (706) (863)
Fireclay!/ 3,247 3,689 3,755 2,959 3,111
(3,581) (4,068) (4,141) (3,263) (3,431)
Bentonite 2>509 2,787 3,002 2,928 3,417
(2,767) (3,073) (3,310) (3,229) (3,768)
Fuller's earth 896 1.032 1,111 1,078 1 181
(988) (1,138) (1,225) (1,189) (1,303)
Common clay 41,837 44,725 40,733 32,040 34 401
Tni-ai (46,127) (49,312) (44.910) (35.326) (37.9?gl
53,926 58,36655,14144,48548,083
(59,456) (64,351) (60,796) (49,047) (53,014)
Imports for consumption 60 48 39 34
(67> (53) (43) (38) (40)
Exports ,]'675, 1'901 2>223 2,099 2,240
(1,847) (2,097) (2,451) (2,315) (2^70)
Apparent consumption 52,312 56,512 52,957 42,420 43 R7Q
(57,676) (62,307) (58,386) (ll'%l) (50J8%
.. T__.,..3 ($1.00 to $200 per short ton), depending on type
and quality.
Stocks, yearend Not A v a i 1 a h i a
Source: Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines
8-44
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Production of miscellaneous clays is tied primarily to the construction
industry, while output of the higher quality clays is not dependent on demand
by a single major industry segment. Miscellaneous clay production is wide-
spread, with all States contributing to the national total in most years.
Fire clay output is also widespread, with over half of the States reporting
production. About half the fire clay output is used for construction products
Output of the other clays is more restricted geographically because of the
lack of resources in many States.
The major world uses for clays are in manufacture of heavy clay con-
struction products, cement, and lightweight aggregates. The more advanced
industrial areas, particularly the United States, Western Europe, Canada,
and Japan, require substantial quantities of the higher quality clays for use
in such products as paper, high-grade ceramics, iron ore pellets, absorbents,
and drilling fluids.
Although there are other materials such as talc, silica, and calcium
carbonate that can be substituted for high-quality clays in many end uses,
the comparatively low cost of clays usually gives them a decided competitive
advantage. Alternative materials, therefore, pose no great threats to the
specialty clay industries; on the contrary, the competition is more likely
to result in increased clay use at the expense of the alternate materials.
For common, or miscellaneous clay, many alternate construction products
and raw materials compete very effectively with brick, tile, and lightweight
aggregates. A few of the major ones are wall panels made of concrete, stone,
glass, metals, and plastics; lightweight aggregates made of pumice, expanded
vermiculite, and sintered fly ash; floor and wall tile made of plastics,
vinyl asbestos, cork, and concrete; and sewer pipe made of concrete, asbestos,
and plastics.
8-45
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8.1.3.2 Feldspar
8.1.3.2.1 General
Feldspar, usually of the potash or soda type or in mixtures of the two,
finds its principal end uses in the manufacture of glass and ceramics; in
both of which applications it acts as a flux. In glassmaking, feldspar
also provides a source of alumina, the presence of which enhances the
workability of the product, inhibits any tendency toward its devitrification,
and increases its chemical stability.
8.1.3.2.2 U.S. Companies/Plants
Crude feldspar is produced in the United States as a primary product
by large diversified firms, by major firms that are primarily feldspar
producers, and by a large number of individuals or groups that mine small
quantities for sale to firms that operate feldspar-grinding plants.
Most of the feldspar used in glass making is ground no finer than 20
mesh while that used in ceramics and filler applications is usually pul-
verized to at least minus 200 mesh.
Nine domestic companies, operating fifteen plants in nine States, ground
feldspar for market in 1974. Listed in descending order of output tonnages,
North Carolina had six grinding mills, while Connecticut, Georgia, and South
Carolina had one each.
8.1.3.2.3 U.S. Production, Consumption and Prices
Salient statistics for the U.S. feldspar industry are presented in the
following table.
8-46
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676
(746)
1
4
(5)
718
(792)
9
(10)
692
(763)
16
(18)
607
(670)
9
(10)
637
(725)
6
(7)
Table 8-17. u-s- FELDSPAR INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
1972 1973 1974 1975 1976
Production
Imports for consumption
Exports
Apparent consumption
Price, average, Mg (per ton) $15.61 $17.86 $16.47 $19.30 $19.85
($14.16) ($16.20) ($14.94) ($17.50) ($18.00)
Ci. , . 225 237 216 216 233
Stocks, producer, yearend (24g) (2g2) (23g) (23g) (257)
Employment: Mine and prepara-
tion plant 450 450 450 450 450
Source: Coranodity Data Summaries Annual, 1977, U.S. Sureau of Mines.
Feldspar is a relatively unimportant item in U.S. foreign trade, although
in some areas, particularly in the northeastern States, a significant proportion
of the feldspathic-materials demand is satisfied by an alternative mineral
product, nepheline syenite, imported from Canada.
Feldspar is a relatively low-priced, bulk commodity that usually can
be produced from some source near the consumer more advantageously than it
can be shipped from a distance.
8.1.3.3 Kyanite
8.1.3.3.1 General
Kyanite, andalusite, and sillimanite are a closely related trio of
aluminum silicate minerals that break down upon heating to form a mixture
of mullite, SAlpOo.ZSiOp, and vitreous silica, SiO^. The properties of
rnullite serve to advantage as a component in refractory shapes and furnace
linings for a wide range of industrial applications.
8-47
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8.1.3.3.2 U.S. Companies/Plants
All but a small part of the domestic kyanite output in recent years has
consisted of the contributions of only two firms. Kyanite Mining Corp.
operates two mines in Virginia, the Willis Mountain mine at Dillwyn in
Buckingham County and the Baker Mountain mine in adjacent Price Edward
County. Commercial ores, Inc., a subsidiary of Combustion Engineering, Inc.,
worked the Henry Knob mine in York County, South Carolina, from 1948 through
1969, and C-E Minerals, Inc., another division of Combustion Engineering, Inc,
has operated the Graves Mountain mine in Lincoln County, Georgia, since 1963.
8.1.3.3.3 U.S. Production, Consumption, and Prices
Salient statistics for the U.S. kyanite industry are presented in the
following table.
Table 8-18. u.s. KYANITE INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
1972 1973 1974 1975 1976
Production: Mine Company confidential data
Synthetic mullite 42.1 52.8 37.6 21 9 27 2
(46.4) (58.2) (41.5) (24.1) (3o!o)
Imports for consumption 0.1 0.2 0.2 0.1 0 1
Exports e/ ,27-2 W-1 40.1 40.1 40.1
J (30.0) (45.0) (45.0) (45.0) (45.0)
Apparent consumption Not Available
Price: Domestic concentrate, 35- to 325- mesh, in bags, f.o.b. Georgia $69-$130/Mg
($63 to $118 per short ton); imported kyanite, no current quotation;
synthetic mullite, $177-$496/Mg ($160 to $450 per short ton), depending
upon type and grade.
Stocks (producer) Not Available
Employment: Kyanite mine ]
and Plant 165 175 175 175 175
Source: Cc.odity Data Shanes annual. 1977, U.S. Sureau of „,„„_
8-48
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In accordance with the policy of the firms involved, no statistics on
U.S. production of kyanite have been released since 1948-49 when the then-
current figure was in the neighborhood of 12,244 Mg (13,500 tons) per year.
Published estimates from various sources since then have placed the U.S. out-
put at about 40,814 Mg (45,000 tons) in 1963 and 85,258 Mg (94,000 tons) in
1973. Both figures, although useful as indicators of magnitudes, are believed
to be moderately in error on the conservative side.
Statistical consumption data is not available. Refractory uses have been
dominant since the early 1920's. Many non-refractory uses for the kyanite-
group minerals and synthesized aluminum silicates have been developed, and
other possible uses appear to have potential for future large-scale applications
In the iron and steel industries, mullite has found important use in
critical areas of blast furnace stoves and stacks, reheat furnaces, steel
degassing chambers and soaking pits, and many types of auxiliary pouring and
handling equipment.
8.1.3.4 Talc
8.1.3.4.1 General
The mineral talc is a soft, hydrous magnesium silicate. Commercial
talcs range from something approaching pure mineral composition to mineral
products that have properties in common with pure talc but which may contain
very little of the actual minerals.
8.1.3.4.2 Company/Plant Statistics
Talc or soapstone was produced domestically in 1974 from 46 mines in
Alabama, Arkansas, California, Georgia, Maryland, Montana, Nevada, New York,
North Carolina, Oregon, Texas, Vermont, Virginia, and Washington.
8-49
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Pyrophyllite was produced from five mines in North Carolina and one mine in
Pennsylvania.
There were 30 producers of talc minerals in the U.S. in 1974. The
plant size range is from 5-18 mg (6 to 20 tons) per hour.
The largest producers of talc minerals in the United States (all
either exclusively engaged in that enterprise or else horizontally inte-
grated subsidiaries of diversified organizations) jointly provided 75
percent of the total 1974 domestic output, and the remainder consisted of
the combined contributions of about 25 smaller firms.
The principal domestic producers of crude talc, soapstone, and
pyrophyllite approached vertical integration to some degree in that they
operated grinding mills, processing their output either in plants adjacent
to the mines or in separate installations more conveniently located with
respect to major markets. Part of the mineral from California and Montana
was milled in Oregon, and a substantial quantity of Montana talc was processed
in Belgium.
Employment in talc, soapstone, and pyrophyllite mines and preparation
plants in 1974 was estimated to be equivalent to the services of about 950
full-time workers.
8.1.3.4.3 U.S. Production, Consumption, and Prices
Salient statistics for the U.S. talc industry are presented in
Table 8-18.
The largest use of talc-group minerals is for the manufacture of ceramics,
In this application, addition of talc or pyrophyllite to the usual clay-silica-
feldspar body mixtures facilitates the firing of the ware and improves the
quality. Second in rank for end use is paint production. Third in order
8-50
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Table 8-19a. u.s. TALC INDUSTRY (in thousand Mg and
thousand short tons in parentheses)
1372 \1973 1974 1975 1976
Production: Mine
Sold by producers
Imports for consumption
Exports
Apparent consumption ]J
Price: $5.50-$276.00/Mg ($5 to $250 per ton) (crude or ground) depending upon
grade and preparation
Stocks oroducpr vearpnd 151 142 188 231 208
btocks, producer, yearend (16?) - (15?) , (m} {25g) (23Q)
1,004
(1,107)
983
(1,084)
26
(29)
155
(171)
854
(942)
1,131
(1,247)
1,073
(1,184)
20
(23)
163
(180)
931
(1,027)
1,150
(1,268)
965
(1,064)
27
(30)
165
(183)
826
(911)
875
(965)
844
(931)
20
(23)
143
(158)
721
(796)
1,028
(1,134)
907
(1,000)
20
(23)
175
(194)
751
(829)
Employment: Mine and mill 950 950 950 950 950
Source: Commodity Data Summaries Annual, 1977, U.S. Bureau of Mines.
among outlets for domestic talc minerals is use for coating and/or loading of
high-quality papers. In this application, high-purity talc helps in obtaining
a product with the desired weight and opacity, good ink retention, and superior
surface texture.
Specific end-use percentages of total consumption are: Ceramics - 17%,
paint - 12%, toilet/cosmetic - 3%, insecticides - 4%, paper - 7%, refractories •
3% roofing - 4% rubber - 2%, and all other minor uses - 46%.
The bulk of the talc, soapstone, and pyrophyllite of commerce is made up
of relatively low-unit-value material unable to bear the charges of long-
distance transportation, but exceptional grades such as high-purity talc of
pharmaceutical, cosmetic, or even papermaking quality are significant items
8-51
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of international trade. The quantities of talc, soapstone, and pyrophyllite
imported and exported by the United States, however, are relatively too small
to exert a decisive influence on the overall pattern of the industry, even
though the total values involved are substantial.
8-52
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8.1.4 Bibliography
The industry structure presented here has been compiled from information
obtained from the United States Bureau of Mines in Washington, D.C. The
Bureau of Mines is considered to be the definitive source for U.S. mineral
industry data. The text is comprised of quoted, paraphrased and edited
material from preprints of the 1975 edition of Mineral Facts and Problems.
Individual physical scientists in the Division of Non-Metallic Minerals at
the Bureau whose reports make up the lion's share of this document are:
1. Sand and gravel: Walter Pajalich, mining engineer, Division of
Non-Metallic Minerals (DNM)
2. Gypsum: Avery H. Reed, Supervisory Physical Scientist, DNM
3. Pumice, Perlite, Arthur C. Meisinger, Industry Economist, DNM
4. Vermiculite: Richard H. Singleton, Physical Scientist, DNM
5. Mica: Stanley K. Haines, Physical Scientist, DNM
6. Barite: Frank B. Fulkerson, Industry Economist, DNM
7. Fluorspar: Hiram B. Wood, Ecologist, DNM
8. Salt: Charles L. Klingman, Physical Scientist, DNM
9. Potash: William F. Keyes, Physical Scientist, DNM
10. Boron: K.P. Wang, Supervisory Physical Scientist, DNM
11. Pyrites: Roland W. Merwin, Supervisory Physical Scientist, DNM
12. Clays: Sarkis G. Ampian, Physical Scientist, DNM
13. Talc, Feldspar: J. Robert Wells, Physical Scientist, DNM
14. Kyanite: Michael J. Potter, Physical Scientist, DNM
Space limitations do not permit listing individual authors' bibliographies
here. The 1975 Mineral Facts and Problems preprints contain these listings
and are available from the Bureau of Mines.
8-53
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Data presented from these reports have been supplemented with the 1955, I960,
1965, 1970, 1971, 1972, and 1973 Minerals Yearbooks (Vol. I): 1974 & 1975
Minerals Yearbook Preprints; 1976 and 1977 Commodity Data Summaries; 1970
edition of Mineral Facts and Problems; 1975 Mineral Facts and Problems
Preprints; Mineral Industry Annual Advance Summaries; and personal communi-
cations with most of the individual authors as well as data clerks and
statisticians at the Bureau of Mines. Certain statistical items are quoted
from "Engineering/Mining Journal", "Pit and Quarry", "Rock Products",
"Chemical Market Reporter" and are referenced in the text. It is neither the
intent nor desire of the editor of this document to claim authorship for all
or any part of the text of the individual industry structures included herein.
8-54
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8.2 COST ANALYSIS OF ALTERNATIVE EMISSION CONTROL SYSTEMS
8.2.1 Introduction
For costing purposes, two model non-metallic plants have been
developed, representative of typical new stationary plants in each of
the 20 industries studied in this document. In addition, costs have
been developed for a model portable plant, typifying a crushed stone
or sand and gravel installation.
The first model plant consists of crushing operations only, and
includes: primary and secondary crushers, screens (3), transfer points
(4) and the. loading operation. The second model plant includes both a
crushing operation and a grinding operation, the latter consisting of a
grinder, another screen, two additional transfer points, and a bagging
machine.
The portable plant is similar to the crushing model plant, in that
it consists of crusher and screens. However, the portable model is,
for practical purposes, much more compact than stationary plants. For
instance, it includes no transfer points or loading facility.
Costs are presented in this section for controlling particulate
emissions from these three model new plants to achieve the alternative
emission level considered in this document.
Particulate control costs have also been developed for expansions
at existing non-metallic minerals plants. The model plant selected here
consists only of a grinding operation, since crushing operations are
usually built with excess capacity, thus obviating the need for additional
equipment. (Refer to Section 8.2.3 for more detailed information.)
8-55
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(Costs have also been developed for monitoring participate
emissions at the model plants. However, since the anticipated new
source performance standard (NSPS) is not expected to require such
monitoring, these costs are treated separately in Section 8.3.)
All control costs have been based on technical parameters associated
with the control system used, such as the plant capacity. These para-
meters are listed in Table 8-19b.
These model plant costs cannot be assumed to reflect costs of any
given installation. Estimating control costs for an actual installation
requires performing detailed engineering studies. Nonetheless, for
purposes of this analysis, model plant costs are considered to be
sufficiently accurate.
The model plant costs have been based primarily on data available
from an EPA contractor (Industrial Gas Cleaning Institute), who had in
turn obtained control system costs from vendors of air pollution control
2
equipment. These costs have been supplemented by a compendium of costs
3
for selected air pollution control systems. The monitoring costs have
o
been obtained from an equipment vendor.
Two cost parameters have been developed: installed capital and total
annualized. The installed capital costs for each emission control system
include the purchased costs of the major and auxiliary equipment, costs
for site preparation and equipment installation, and design engineering costs
No attempt has been made to include costs for research and development,
possible lost production during equipment installation, or losses during
startup. All capital costs in this section reflect fourth quarter 1976
prices for equipment, installation materials, and installation labor.
8-56
-------
Table 8-19b. TECHNICAL PARAMETERS USED IN DEVELOPING
CONTROL SYSTEM COSTS9
Parameter Value
1. Temperature 21°C (70°F)
2. Volumetric flowrate (See Tables 8-21 to 8-32, 8-37, & 8-38)
3. Moisture content 2 percent (by volume)
3. Particulate loadings:
Inlet 12.8 g/Nm3 (5.6 grains/scf)
Outlet 0.050 g/Nm3 (0.02 grains/scf)
4. Plant capacities 9,1, 23, 68, 135,180, 270, and 540 Mg/hr
(10, 25, 75, 150, 200, 300, and 600 tons/hr
5. Operating factors:
Crushing operations 2,000 hours/year
Grinding operations 8,400 hours/year
Reference
capacities represent the sizes typical of generalized model plants.
However, for a particular industry, only some of these sizes are applicable.
o
-57
-------
The total annualized costs consist of direct operating costs and
annualized capital charges. Direct operating costs include fixed and
variable annual costs, such as:
« Labor and materials needed to operate control equipment;
• Maintenance labor and materials;
• Utilities, such as electric power;
• Replacement parts;
• Dust disposal (where applicable).
The dust disposal costs apply only to dry collection systems
(i.e., fabric filters) used to control crushing operations when no
grinding operations are employed. A unit cost of $4.40/Mg ($4/ton) is
used to cover the costs of trucking the collected particulate to a
disposal point on-site (e.g., the mine).
In those plants that have both crushing and grinding operations,
the dust collected by the crusher baghouses is conveyed to the grinder,
while the particulate captured by the grinder fabric filter is recycled
as finished product. In this case, it has been assumed that the dust
recovery credit offsets the cost of recycling. That is, neither a
dust credit nor a cost is included in the direct operating cost.
The annualized capital charges account for depreciation, interest,
administrative overhead, property taxes, and insurance. The depreciation
and interest have been computed by use of a capital recovery factor, the
value of which depends on the depreciable life of the control system and
the interest rate. (An annual interest rate of 10 percent and a 20 year
depreciable life have been assumed herein.) Administrative overhead,
8-58
-------
taxes, and insurance have been fixed at an additional 4 percent of the
installed capital cost per year. The annual cost factors used in this
section are listed in Table 8-20.
Finally, the total annualized cost is obtained simply by adding the
direct operating cost to the annualized capital charges.
8.2.2 New Facilities
As discussed in section 8.2.1, three new model plants have been
developed for costing purposes: a stationary installation with crushing
operations only (Model Plant 1), another stationary with both crushing
and grinding operations (Model Plant 2), and a portable installation.
For all models, the alternative emission level to be achieved is 0.050
g/dscm (0.02 grains/dscf). The control option to be used to achieve this
emission level is fabric filtration. At an uncontrolled emission rate of
12.8 g/dscm (5.6 grains/dscf) (see Table 8-19), this control o.ption is
99.6 percent efficient in removing particulate at the model plants.
The size and number of fabric filter systems required to achieve the
emission limit vary according to the mineral plant capacity. For example,
only two moderately-sized baghouses are required to control the crushing
and grinding operations at the 9.1 Mg/hour (10 tons/hour) model plant,
while four much larger fabric filters are needed at the 540 Mg/hour (600
tons/hour) model.
Each of these fabric filter systems consists of a pulse-jet baghouse
with polypropylene bags, fan and fan motor, dust hopper, screw conveyor,
ductwork, and stack.
8-59
-------
Table 8-20. ANNUALIZED COST PARAMETERS'
Parameter
Value
1. Operating Labor
2. Maintenance Labor
3. Maintenance Materials
4. Utilities:
Electric Power
5. Replacement Parts:
Polypropylene Bags
6. Dust disposal
7. Depreciation and Interest
8. Taxes, Insurance, and Adminis-
trative Charges
$10/man-hour
50 percent of operating labor (fabric
fi1ters)
40 man-hours/year (opacity monitors)
2 percent of maintenance labor (fabric
filters)
1 percent of total installed cost
(opacity monitors)
$0.03/kw-hr
$7.00/m2 ($0.65/ft2)
$4.40/Mg ($4.00/ton)
11.75 percent of total installed cost
(fabric filters)
16.28 percent of total installed cost
(opacity monitors)
4.0 percent of total installed cost
References 2, 3, 4, and EPA estimates.
8-60
-------
Tables 8-21 through 8-26 list installed capital, direct operating,
annualized capital, and total annualized costs for each of the fabric
filter systems installed in the new Model Plants 1. The six plant sizes
for which costs have been developed cover the range in capacities applicable
to the various mineral industries.
In Tables 8-21 through 8-24, the first column lists the technical or
cost parameter in question. The data pertaining to the fabric filter
are listed in the second column. However, in each of Tables 8-25 and
8-26, more than one fabric filter are needed to control the crushing
operation. The data for these fabric filters appear in columns 2, 3, etc.,
while the right-hand column lists the totals for the model plant.
Similarly, Tables 8-27 through 8-32 contain cost data for Model Plant 2.
The costs are itemized according to the fabric filters controlling the
crusher and grinder operations, respectively. Again, the right-hand
column lists data for the total model plant. Note that the installed
capital costs and annualized capital charges for the crusher baghouse(s)
are the same as in the corresponding tables for Model Plant 1. However,
because no dust disposal costs are included with Model Plant 2, the direct
operating costs—and the total annual ized costs—are lower.
Finally, Table 8-33 displays cost for a 180 Mg/hour (200 TPH) portable model
plant, which is solely applicable to crushed stone and the sand and gravel
industries. Because these kinds of plants employ only crushing operations,
the model plant includes no grinding facility.
In these tables, the total annualized cost has been expressed in two
ways: thousand dollars/year and dollars/megagram of product. The latter
expression is the quotient of the total annual ized cost and the annual
8-61
-------
Table 8-21 FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 9.1 Mg/Hour
(10 tons/hour) Capacity3
Parameter
CO
I
01
Gas flowrate, nr/min. (ACFM)
Installed capital cost, M$
Direct operating cost, M$/yr
Annualized capital charges, M$/yr
Total annualized cost, M$/yr
$/Mg product0
Cost-effecti veness,-$/Mg
particulate removed0
value
289
(10,200)
60
4.7
9.5
14.2
0.78
32.1
References 1 to 4.
The letter "M" denotes thousands; "MM" denotes millions, etc.
Quotients are based on 2,000 hours/year operating factor.
-------
Table 8-22 FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 23 Mg/Hour
(25 tons/hour) Capacity3
Parameter
CO
I
CT>
CJ
Gas flowrate, nr/min (ACFM)
Installed capital cost, M$b
Direct operating cost, M$/yr
Annualized capital charges, M$/yr
Total annualized cost, $/yr
$/Mg product0
Cost-effectiveness, $/Mg
particulate removedc
Value
325
(11,500)
67
5.3
J0_.5
15.8
0.34
31.7
References 1 to 4.
DThe letter "M" denotes thousands; "MM" denotes millions, etc.
-.
"Quotients based on 2,000 hours/year operating factor.
-------
Table 8-23 FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 68 Mg/Hour
(75 tons/hour) Capacity
Parameter
oo
CT>
Gas flowrate, nr/min (ACFM)
Installed capital cost, M$
Direct operating cost, M$/yr
Annualized capital charges, M$/yr
Total annualized cost, M$/yr
$/Mg product0
Cost-effectiveness, $/Mg
particulate removed
Value
504
(17,800)
95
8.4
15.0
23.4
0.17
30.3
References 1 to 4.
DThe letter "M" denotes thousands; "MM" denotes millions, etc.
'Quotients are based on 2,000 hours/year operating factor.
-------
Table 8-24. FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 135 Mg/Hour
(150 tons/hour) Capacity3
Parameter
CD
CT)
cn
Gas flowrate, nr/min (ACFM)
Installed capital cost, M$b
Direct operating cost, M$/yr
Annualized capital charges, M$/yr
Total annualized cost, M$/yr
$/Mg product0
Cost-effectiveness, $/Mg
particulate removedc
Value
708
(25,000)
122
11.9
19.2
31.1
0.12
28.7
References 1 to 4.
The letter "M" denotes thousands; "MM" denotes millions, etc.
cQuotients are based on 2,000 hours/year operating factor.
-------
Table 8-25. FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 270 Mg/Hour
(300 tons/hour) Capacity3
Parameter
Gas flowrate, m3/min (ACFM)
Installed capital cost, M$
Direct operating cost, M$/yr
Annualized capital charges, M$/yr
Total annual ized cost, M$/yr
$/Mg product0
Cost-effectiveness, $/Mg
particulate removed0
Value
Fabric Filter 1
1,130
(40,000)
161
18.6
25.3
43.9
0.081
25.3
Fabric Filter 2
226
(8,000)
50
3.7
7.9
11.6
0.021
33.5
Total
1,360
(48,000)
211
22.3
33.2
55.5
0.10
26.7
References 1 to 4.
3The letter "M" denotes thousands; "MM", denotes millions, etc.
•*
"Quotients are based on 2,000 hours/year operating factor.
-------
Table 8-26. FABRIC FILTER COSTS FOR NEW MODEL PLANT 1: 540 Mg/Hour
(600 tons/hour) Capacity3
Parameter
Gas flowrate, m3/min (ACFM)
Installed capital cost, M$b
Direct operating cost, M$/yr
Annual ized capital charges, M$/yr
Total annual ized cost, M$/yr
$/Mg product0
Cost-effectiveness, $/Mg
particulate removed0
Value
Fabric Filter 1
225
(9,000)
54
4.1
8.5
12.6
0.012
32.3
Fabric Filter 2
906
(32,000)
142
15.1
22.4
37.5
0.035
27.0
Fabric Filter 3
877
(31,000)
140
14.6
_22_._1
36.7
0.034
27.3
Total
2,040
(72,000)
336
33.9
53.0
86.9
0.080
27.8
CO
CTl
References 1 to 4.
The letter "M" denotes thousands; "MM" denotes millions, etc.
Quotients are based on 2,000 hours/year operating factor.
-------
Table 8-27. FABRIC FILTER COSTS FOR NEW MODEL PLANT 2:
(10 tons/hour) Capacity3
9.1 Mg/Hour
Value
Parameter
Operation controlled
Gas flowrate, m /min. ACFM
Installed capital cost, M$c
Direct operating cost, M$/yr
Annual ized capital charges, M$/yr
Total annual ized cost, M$/yr ,
$/Mg Product
Cost-effectiveness, $/Mg particulate
removedd
Fabric Filter 1
Crushing
289
(10,200)
60
2.7
9.5
12.2
0.67
27.6
Fabric Filter 2
Grinding
113
(4,000)
33
3.8
5.2
9.0
0.12
12.4
Totalb
—
--
93
6.5
14.7
21.2
0.28
18.2
References 1 to 3.
DNumbers in the right-hand column pertain to combined crushing and grinding operations.
"The letter "M" denotes thousands; "MM" denotes millions, etc.
Quotients for crushing are based on 2,000 hours/year operating factor; grinding quotients
based on 8,400 hours/year.
-------
Table 8-28. FABRIC FILTER COSTS FOR NEW MODEL PLANT 2: 23 Mg/Hour
(25 tons/hour) Capacity^
Parameter
Operation controlled
Gas flowrate, m3/min (ACFM)
Installed capital cost, M$c
Direct operating cost, M$/yr
Annualized capital charges, M$/yr
Total annual i zed cost, $/yr,
$/Mg product
Cost-effectiveness, $/Mg
parti cul ate removed^
Value
Fabric Filter 1
Crushing
325
(11,500)
67
3.1
10.5
13.6
0.30
27.4
Fabric Filter 2
Grinding
133
(4,700)
36
4.1
5.7
9.8
0.05
11.5
Total5
_ _
--
103
7.2
16.2
23,4
0.12
17.3
oo
i
cr>
us
References 1 to 3.
^Numbers in the right-hand column pertain to combined crushing and grinding operations.
'The letter "M" denotes thousands; "MM" denotes millions, etc.
Quotients for crushing based on 2,000 hours/year operating factor; grinding quotients based on
8,400 hours/year.
-------
Table 8-29. FABRIC FILTER COSTS FOR NEW MODEL PLANT 2: 68 Mg/Hour
(75 tons/hour) Capacity3
Parameter
Operation controlled
Gas flowrate, m3/min (ACFM)
p
Installed capital cost, M$
Direct operating cost,M$/yr
Annual ized capital charges, M$/yr
Total annual ized cost, M$/yr
$/Mg product01
Cost-effectiveness, $/Mg
particulate removedd
Value
Fabric Filter 1
Crushing
504
(17,800)
95
5.0
15.0
20.0
0.15
25.9
Fabric Filter 2
Grinding
190
(6,700)
44
5.1
6.9
12.0
0.021
9.83
Totalb
__
139
10.1
21.9
32.0
0.056
16.1
^References 1 to 3.
Numbers in the right-hand column pertain to combined crushing and grinding operations.
cThe letter "M" denotes thousands; "MM" denotes millions, etc.
Quotients for crushing are based on 2,000 hours/year operating factor; grinding quotients
based on 8,400 hours/year.
-------
Table 8-30. FABRIC FILTER COSTS FOR NEW MODEL PLANT 2: 135 Mg/hour
(150 tons/hour) Capacity3
Parameter
Operation controlled
Gas flowrate, m3/min (ACFM)
Installed capital cost, M$c
Direct operating cost, M$/yr
Annual ized capital charges, M$/yr
Total annual ized cost, M$/yr
$/Mg productd
Cost-effectiveness, $/Mg particulat
removed
Va
Fabric Filter 1
Crushing
708
(25,000)
122
7.1
19.2
26.3
0.097
e 24.3
lue
Fabric Filter 2
Grinding
320
(11,300)
65
7.8
10.3
18.1
0.016
8.80
Total5
—
187
14.9
29.5
44.4
0.039
14.1
00
I
References 1 to 3.
^Numbers in the right-hand column pertain to combined crushing and grinding operations.
'The letter "M" denotes thousands; "MM" denotes millions, etc.
Quotients for crushing are based on 2,000 hours/year operating factor; grinding quotients
based on 8,400 hours/year.
-------
Table 8-31. FABRIC FILTER COSTS FOR NEW MODEL PLANT 2: 270 Mg/Hour
(300 tons/hour) Capacity3
Parameter
Operation controlled
Gas flowrate, m/min (ACFM)
Installed capital cost, M$c
Direct operating cost,M$/yr
Annual ized capital charges, M$/yr
Total annual ized cost ,M$/yr
$/Mg productd
Cost-effectiveness, $/Mg participate
removed
Value
. _ i-
Fabric Filter 1
Crushing
1,130
(40,000)
161
10.9
25.3
36.2
0.067
20.9
Fabric Filter 2
Crushing
226
(8,000)
50
2.2
7.9
10.1
0.019
29.2
Fabric Filter 3
Grinding
640
(22,600)
113
17.4
1LJL
35.2
0.016
8.56
Total"
__
--
324
30.5
51.0
81.5
0.036
13.2
References 1 to 3.
lumbers in the right-hand column pertain to combined crushing and grinding operations.
"The letter "M" denotes thousands; "MM" denotes millions, etc.
Quotients for crushing are based on 2,000 hours/year operating factor; grinding quotients based on
8,400 hours/year.
-------
Table 8-32.
FABRIC FILTER COSTS FOR NEW MODEL PLANT 2: 540 Mg/Hour
(600 tons/hour) Capacity3
Parameter
Operation controlled
Gas flowrate, m3/min (ACFM)
Installed capital cost, M$c
Direct operating cost, M$/yr
Annualized capital charges, M$/yr
Total annual ized cost, M$/yr
$/Mg productd
Cost-effectiveness, $/Mg
particulate removedd
Va
Fabric
Filter 1
Crushing
255
(9,000)
54
2.4
UL
10.9
0.010
27.9
Fabric
Filter 2
Crushing
906
(32,000)
142
9.0
22.4.
31.4
0.029
22.7
ue
Fabric
Filter 3
Crushing
877
(31,000)
140
8.7
2JM
30.8
0.029
23.0
Fabric
Filter 4
Grinding
1,280
(45,200)
171
31.1
26.9
58.0
0.013
7.05
Total5
--
_-
507
51.2
79.9
131.1
Oo029
11.6
CO
I
CO
References 1 to 3.
''Numbers in the right-hand column pertain to combined crushing and grinding operations.
'The letter "M" denotes thousands; "MM" denotes millions, etc.
Quotients for crushing are based on 2,000 hours/year operating factor; grinding quotients based on
8,400 hours/year.
-------
Table 8-33. FABRIC FILTER COSTS FOR PORTABLE MODEL PLANT: 180 Mg/Hour
(200 tons/hour) Capacity3'13
Parameter
Gas flowrate, m3/min (ACFM)
Installed capital cost, M$c
Direct operating cost, M$/yr.
Annual ized capital charges, M$/yr.
Total annual ized cost, M$/yr.
$/Mg productd
Cost-effectiveness, $/Mg
particulate removedd
Value
Fabric Filter 1
453
(16,000)
87
7.5
13.7
21.2
0.059
30.5
Fabric Filter
113
(4,000)
33
2.1
5.2
7.3
0.020
42.1
Total
566
(20,000)
120
9.6
18.9
28.5
0.079
32.8
References 1 to 4.
3This model plant applies to the crushed stone and sand and gravel industries only.
"The letter "M" denotes thousands; "MM" denotes millions, etc.
Quotients are based on 2,000 hours/year operating factor.
-------
production rate, based, in turn, on the operating factor. As Table
8-19 indicates, crushing operations (i.e., Model Plant 1 and the portable
model plant) are assigned an operating factor of 2,000 hours/year, while
with grinding operations, 8,400 hours/year has been used. For Model Plant
2, where both crushing and grinding operations are employed, 8,400
hours/year is used as the operating factor, solely for the purpose of
computing the unit annualized costs.
Each cost-effectiveness ratio appearing in the tables is simply the
quotient of the total annualized cost and the amount of particulate
collected annually by the fabric filter system. To compute the parti-
culate collected, the 2,000 and 8,400 hours/year operating factors are
applied, respectively, to the individual crushing and grinding operations.
However, for combined crushing and grinding operations, the following
expression has been used to calculate cost-effectiveness:
TACC + TACQ
Cost-effectiveness =
/*,„ 4.. i * 7.65 x 10"7 (2000Qr + 84000-)
($/Mg particulate C XG'
removed)
Where: TACf, TACp = total annualized costs for crushing and
grinding baghouses, respectively (M$/year)
Qr, Qr = total volumetric flowrates for crushing,
and grinding baghouses, respectively (m /min)
The numerator is the sum of the annualized costs for the crushing
and grinding operations, while the denominator represents the total
amount of particulate removed by the fabric filters controlling these
operations. (Cost-effectiveness is further discussed in Section 8.2.4.)
8-75
-------
As the tables indicate, the installed costs in the crushing (only)
model plant range from $60,000 to $336,000, as the plant capacity goes
from 9.1 Mg/hour to 540 Mg/hour. However, given the sixty-fold increase
in the plant capacity, the installed costs increase relatively little.
This is so because the fabric filter installed costs are a function of
the volumetric flowrate, not the plant capacity. Moreover, the volumetric
flowrate, while dependent on the capacity, does not increase proportionately
with the plant size.
Based on a 2000 hour operating year, the total annualized cost increases
from $14,000 to $87,000 per year, corresponding to $0.78 to $0.08/Mg
product, as the plant capacity goes from 9.1 to 540 Mg/hour. Ordinarily,
one would also expect a more substantial increase in the total annualized
cost over such a large range in plant capacities. However, as Tables
8-21 through 8-26 show, the annualized capital charges comprise the bulk
of the total annualized costs. And since the annualized capital charges
are directly proportional to the installed costs, the total annualized
cost very nearly follows the change in the capital cost.
There are several reasons why the direct operating costs are so low.
First, because the gas streams controlled are non-corrosive and low-
temperature, the fabric filter maintenance is relatively small, amounting
to less than one percent of the installed cost annually. Then, because
there is a relatively small pressure drop through the baghouse system,
the power cost is relatively low. Costs for replacement parts (i.e.,
bags) are proportional to the gas flowrate, but at the same time amount
to a small fraction of the direct operating costs.
8-76
-------
A similar pattern appears with the costs for Model Plant 2, which
contains both crushing and grinding operations. The costs here are about
the same order of magnitude as are those for Model Plant 1. The main
difference is the additional baghouse required to control the grinder
and its auxiliaries. Here the installed costs range from $93,000 to
$507,000, while the annualized costs go from $21,000 ,to $131,000 per
year ($0.28 to $0.03/Mg product, respectively).
Though the capacity for the portable plant (180 Mg/hour) is higher
than the 135 Mg/hour stationary Model Plant 1, its total annualized cost
is slightly lower than the cost shown in Table 8-24. This table and
Table 8-33 show why this anomaly occurs. First, the portable plant
3
requires two fabric filters, one sized for 455 m /min, the other at
3
113 m /min. But together, the flowrates are less than the flowrate
(708 m /min) given for the single baghouse controlling the 135 Mg/hour
crushing model plant. This smaller flowrate, in turn, is attributable to
the compactness of the portable plant, relative to stationary installations,
As the tables indicate, the unit annualized costs (expressed in
dollars per megagram of product) decrease consistently with increasing
plant size, indicating that the model plants benefit from a positive
economy of scale.
The costs described above are for achieving the alternative emission
level. It is also necessary to compare these costs to the costs required
to meet a typical state emission regulation (SIP) in the model plants.
In this analysis, however, it is assumed that the SIP can be met without
controls. The SIP or baseline costs are, therefore, zero. Thus, the costs
shown in Tables 8-21 to 8-33 are solely attributable to the alternative
emission limit.
8-77
-------
8.2.3 Modified/Reconstructed Faci1ities
As Chapter 5 points out, there appears to be no condition which
would deem an existing plant modified. Concerning reconstruction,
if replacement of components subject to high abrasion and impact,
such as crushing and screening surfaces and conveyor belts,
are exempted and considered routine for this category of sources,
there also appears to be no action which could be construed as recon-
struction.
Nonetheless, expansions of existing plants do occur. When they do,
only a portion of the plant would be covered under the alternative
emission limit. These expansions would more than likely involve the
grinding operation, since crushing operations are usually capable of
handling increased throughput without additional equipment. However, to
expand the plant grinding capacity, a new complete grinding line would
be added.
In this document, sizes for three stationary model plants have been
developed to cover these expansions: 4.5, 9.1, and 32 Mg/hour (5,10,
and 35 tons/hour). The first two sizes apply to all industries employing
grinders (i.e., Model Plant 2). The third size applies only to the boron
industry.
The option costed for controlling these expanded model plants is
fabric filtration. The gas flowrates used in the costing are listed in
Tables 8-34 and 8-35. The other technical parameters appear in Table 8-19
Because these fabric filters would be installed at existing, as
opposed to new plants, the installed capital costs are somewhat higher,
8-78
-------
reflecting the higher installation costs required. The difference
between the existing and new plant installation costs, or retrofit penalty,
is quite variable, depending on individual plant configuration, on-site
utility capacity, and other seemingly random variables. Nonetheless,
after polling its members, the Industrial Gas Cleaning Institute has
developed an approximate multiplier, or retrofit factor, to be used in
estimating the existing plant installation costs. This retrofit factor
is 2.0. Using this factor, the control system existing plant installation
cost would be twice that of the new plant installation cost.
Table 8-34 lists the costs of fabric filter systems installed in
the expanded 4.5 and 9.1 Mg/hour model plants. The 32 Mg/hour capacity
model plant costs are listed in Table 8-35.
The installed costs in Table 8-34 are $43,000 and $48,000 for the
4.5 and 9.1 Mg/hour plants, respectively. The installed cost difference
is relatively small: 10 percent. However, this is because the gas flow-
rates upon which the costs are based differ by only 23 percent, even
though one plant size is twice the other. The total annualized costs
differ much less: $10,200/year for the 4.5 Mg/hour size, and $ll,300/year
for the 9.1 Mg/hour case. (Because these baghouses control grinders,
neither of these costs includes a cost for dust disposal.)
Since grinding operations need not be controlled to achieve a state
regulation, the SIP costs are zero. The annualized costs shown in Table
8-34 are, therefore, both total and incremental. These incremental costs
are $0.27 and $0.15/Mg product, in turn, for the 4.5 and 9.1 Mg/hour
capacity plants. Both numbers have been based on an 8400 hours/year
operating factor. The 44 percent decrease in cost indicates a positive
economy of scale with plant capacity.
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Table 3-34. FABRIC FILTER COSTS FOR EXPANDED MODEL PLANTS
a,b
Value, by Capacity
Parameter
Gas flowrate, m3/min (ACFM)
Installed capital cost, M$c
Direct operating cost, M3/yr
Annualized capital charges, M$>
Total annualized cost, M Vyr
$/Mg product6
4.5 Mg/Hour
92.0 (3,250)
43
3.4
'yr 6.8
10.2
0.27
9.1 Mg/Hour
113 (4,000)
43
3.8
7.5
11.3
0.15
References 1, 2, 3, and 5.
Expanded plants consist of grinding operations only.
cThe letter "M" denotes thousands; "MM" denotes millions, etc.
cL.
Since SIP control cost is zero, total and incremental annualized costs are equal
"Quotients are based on an 8,400 hours/year operating factor.
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Parameter
Table 8-35. FABRIC FILTER COSTS FOR 32 Ma/Hour
EXPANDED MODEL PLANT3'0
Value
Gas flowrate, m3/min (ACFM)
Installed capital cost, M$c
Direct operating cost, M$/yr.
Annualized capital charges, M$/yr,
Total annualized cost
M$/year
$/Mg product6
184 (6,500)
65
5.0
10.2
15.2
0.057
References 1, 2, 3, and 5.
This capacity applies to the boron industry only
GThe letter "M" denotes thousands; "MM" denotes millions, etc.
Since SIP control cost is zero, total and incremental annualized costs are equal
Quotients are based on an 8,400 hours/year operating factor.
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Finally, the fabric filter costs for the 32 Mg/hour expanded model
o
plant are listed in Table 8-35. Sized for a gas flowrate of 184 m /min,
the installed cost is $65,000. The corresponding incremental annualized
cost is $15,200 per year, or $0.06/Mg product, based on the same 8400
hours/year operating factor.
8.2.4 Cost-Effectiveness of the Alternative Emission Limit
For each of the control options costed to achieve the alternative
emission limit, it is informative to compare the total annualized cost
with the amount of particulate removed. A convenient yardstick for
expressing this comparison is the cost-effectiveness ratio, which is
the quotient of the annualized cost and the quantity of particulate
removed annually. Expressed in dollars per megagram of particulate,
these ratios appear in Tables 8-21 through 8-33, for the stationary and
portable new model plant sizes costed herein. (Because an NSPS impacts
most heavily on new, rather than existing plants, the cost-effectiveness
analysis will be limited to them.)
It is clear from these tables that the ratios vary according to the
plant capacity, design (stationary or portable), and the model plant
configuration (i.e., Model Plant 1 or 2). For Model Plant 1 (crushing
only), the cost-effectiveness ranges from $32.1 to $27.8/Mg, as the
capacity goes from 9.1 to 540 Mg/hour. The corresponding ratios for
Model Plant 2 (crushing and grinding) are $18.2 and $11.6/Mg particulate
removed. The cost-effectiveness for the portable model plant (180 Mg/hour
capacity) is $32.8/Mg.
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The ratios are plotted in Figure 8-1 against the model plant
capacity. Note, first of all, that with Model Plant 2, the cost-
effectiveness decreases from $18.2 to $14.1/Mg (23 percent) between
the 9.1 and 135 Mg/hour plant capacities. At larger sizes, however,
this rate of decrease is much less pronounced. In fact, the cost-
effectiveness ratio decreases only 18 percent between 135 and 540 Mg/hour
Nonetheless, the fact that the ratio decreases consistently with plant
size indicates that the control costs for Model Plant 2 benefit from a
positive economy of scale.
The curve for Model Plant 1 does not exhibit this consistency,
however. Note that the cost-effectiveness decreases gradually from a
maximum of $32.1/Mg to a minimum of $26.5/Mg. This minimum occurs at a
plant capacity of about 340 Mg/hour. But for larger plant sizes, the
curve swings upward, reaching a value of $27.8/Mg at the 540 Mg/hour
capacity. This behavior indicates a negative economy of scale with
respect to plant size.
The following explanation can be offered for this anomaly. First
of all, the fabric filter costs represented by Figure 8-1 are functions
of the gas volumetric flowrate, not the plant capacity. Secondly, the
cost-effectiveness ratio is also a function of the volumetric flowrate,
as well as the annual operating hours. Now, when a model plant consists
of more than one fabric filter system, the mean cost-effectiveness ratio
for the model plant is strongly affected by the volumetric flowrates
of the individual fabric filter systems. (The equation in Section 8.2.2
bears this out.) For instance, if one fabric filter flowrate is much
smaller or larger than the others, the mean cost-effectiveness will be
weighted toward that flowrate.
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oo
s.
-------
Such a situation is illustrated by the data in Tables 8-25 and 8-26,
for the 270 and 540 Mg/hour model plants, respectively. In Table 8-25,
data for two fabric filters are presented, one of which is sized for five
times the flowrate as the other. Accordingly, the mean cost-effectiveness
($26.7/Mg) is heavily weighted toward the larger fabric filter. But with
the 540 Mg/hour model plant (Table 8-26), there are three fabric filters,
o
sized at 255, 877, and 906 m /min. Since two of these fabric filters are
approximately equal in size, the mean cost-effectiveness for the model plant
($27.8/Mg) is weighted toward them. Note, moreover, that this ratio is
higher than that for the 270 Mg/hour plant. This, in turn, accounts for
the dip in the curve in Figure 8-1.
Also, note that the mean cost-effectiveness ratio for the portable
plant is higher than the corresponding value for Model Plant 1. The
difference is partly attributable to the lower gas flowrate required with
the portable plant, compared with the crushing model plant. (That is,
the lower the flowrate, the higher the cost-effectiveness ratio, other
things being equal.) Moreover, the mean cost-effectiveness ratio for the
portable plant is biased upward by the smaller fabric filter, which is
o 3
sized at 113 m /min versus the 453 m /min larger baghouse.
8.2.5 Control Cost Comparison
Before the accuracy and representativeness of model plant control
costs can be ascertained, they must be compared with costs obtained from
other data sources. In doing this, one can either compare the installed
capital costs, the annualized costs, or both. However, since the capital
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costs influence the annualized costs (via the annualized capital charges),
and because there is much more variability among the several terms in the
annualized cost (utilities, for instance), it is preferable to limit the
comparison to the installed costs.
Even for a control system sized for a specific emission point, the
installed cost may vary considerably from site-to-site. Such things as
the cost of installation labor (electricians, pipefitters, etc.), the
requirement for special installation, materials (e.g., extra insulation for
systems installed in colder climates)^ a^d>the presence or absence of
excess utility capacity considerably influence the total installed cost.
Keeping this in mind, however, capital cost comparisons can be made,
among a range of control system sizes. This comparison may be made
graphically; that is, installed costs adjusted to the same reference date
(December 1976, in this case) can be plotted against some technical parameter
relevant to the control system. In this section, installed costs are
compared among various sizes of fabric filter systems, using gas volumetric
flowrate as the comparison parameter.
The model plant costs are compared with cost data obtained from
industry sources ' and with costs developed in-house from a compendium
of air pollution control costs (the GARD Manual). These costs have been
plotted against volumetric flowrate on full logarithmic paper (Figure 8-2).
For all flowrates in the domain of 42 to 1,400 actual m3/min, the costs
developed from the GARD Manual are higher than the model plant costs. The
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10C
Figure 8-2. Installed Costs of Fabric
Filter Systems
Reference 3
Reference 6
CO
I
00
S
to
c.
Model Plant (IGCI)
Reference 7
10
10
10'
Volumetric Flowrate (m /min)
-------
discrepancy ranges from 17 to 32 percent, the higher difference corresponding
o
to 42 m /min. The cost curve for reference 6 intersects the model plant
o
curve at 115 m /min. (This is approximately the size of the grinding
operation baghouse in the 9.1 Mg/hour model plant.) Below this flowrate
the reference 6 costs are lower; above it, they are higher, but by no more
than 53 percent. The last fabric filter cost curve (reference 7) lies
consistently below the model plant curve for all flowrates between 28 and
3
1,050 m /min. However, the differences between the costs--7 to 18 percent—are
not significant.
All in all, the model plant fabric filter costs compare reasonably well
with the data supplied by references 3, 6, and 7.
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8.3 OTHER COST CONSIDERATIONS
As discussed in Section 8.2, it is unlikely that non-metallic minerals
plants covered under the anticipated NSPS would be required to monitor the
opacity of their particulate emissions. Nonetheless, for the benefit of
those plants considering an opacity monitoring program, costs are presented
for these devices in this section.
Continuous monitoring of opacity usually involves the use of a trans-
mi ssometer installed in a fabric filter stack. This instrument relates
the transmittance of a light beam across the stack to the opacity of
the exhaust . These devices are fully automatic and usually require only
periodic maintenance. (However, manual stack testing may be required for
calibration of the instrument.)
Table 8-36 lists costs for a typical opacity monitoring system
o
obtained from an instrument vendor. The system shown consists of a
visible emission monitor, controls, data readout-converter, strip chart
recorder, and other auxiliaries. Of the $20,000 installed cost, half
is the equipment purchase cost, the other $10,000 is for installation.
It has been assumed that no scaffolding would have to be erected on the
stack being monitored. However, if scaffolding is required, the installation
cost could increase appreciably. The scaffolding cost would, as expected,
vary from site to site. For instance, the cost of scaffolding a 50-foot
"stub" stack (the kind normally used with nonmetallic minerals plant
fabric filters) would be $20,000 to $30,000.
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Table 8-36. MONITORING COSTS FOR NON-METALLIC MINERALS MODEL PLANTS3'b
Parameter
Operating factor, hours/year
Installed capital cost, M$
Direct operating cost, M$/year
Annual i zed capital charges, M$/year
Total annual ized cost, $/year
Value
2000
20
0.7
4,1
4.8
8400
20
1.0
4.1
5.1
Reference 8.
DThese costs are for opacity monitoring of one stack. No scaffolding
costs are included.
'The letter "M" denotes thousands; "MM" denotes millions, etc.
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The direct operating costs have been computed at the 2000 and 8400
hours/year operating factors. Here, the only cost sensitive to a change
in the operating factor is the electric power cost. At the lower operating
factor (corresponding to the crushing model plant) the power cost is $100/year
against $420/year at 8400 hours/year of operation. The rest of the direct
operating cost is for maintenance of the monitoring system, which amounts to
3 percent of the installed cost.
The annualized capital changes have been computed assuming a ten-year
life and a ten percent annual interest rate, plus four percent of the
installed cost for taxes, insurance, and administrative charges. Depending
on the operating factor, the total annualized cost is either $4,800 or
$5,100 per year.
For the smaller model plants, these amounts are appreciable--one-third
of the fabric filter total annualized costs at the 9.1 Mg/hour Model Plant 1.
However, with the larger plants, more than one baghouse would need to be
monitored. Thus, their monitoring costs could be two or more times the
costs in Table 8-36. In other words, there is little or no economy of
scale in the costs for monitoring multiple stacks. This is so because
each stack requires separate opacity instrumentation, scaffolding, and other
equipment. The only savings would result from some parts of the installation
cost, such as engineering. But these latter costs, when taken together,
generally comprise only a small fraction of the installed cost.
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References for Sections 8.2 and 8.3
1. Written communications between William M. Vatavuk (Economic Analysis
Branch, Strategies and Air Standards Division) and James A. Eddinger,
(Industrial Studies Branch, Emission Standards and Engineering Division).
Dates: August 18, 1976; June 15, June 30, July 8, 1977; and February 9,
March 17, and April 20, 1978.
2. Nonmetallic Minerals Industries Control Equipment Costs. Prepared by:
Industrial Gas Cleaning Institute (Stamford, Connecticut). Prepared
for: U.S. Environmental Protection Agency, Strategies and Air Standards
Division, Economic Analysis Branch (Research Triangle Park, North
Carolina). Contract No. 68-02-1473, Task No. 19. February 1977.
3. Kinkley, M.I. and R.B. Neveril. Capital and Operating Costs of
Selected Air Pollution Control Systems. Prepared by: GARD, Inc.
(Miles, Illinois).Prepared for: U.S. Environmental Protection Agency
Strategies and Air Standards Division, Economic Analysis Branch (Research
Triangle Park, North Carolina). Contract No. 68-02-2072. May 1976.
4. McGlamery, G.G., et al. Detailed Cost Estimates for Advanced Effluent
Desulfurization Processes. Prepared by: Tennessee Valley Authority,
Muscle Shoals, Alabama, under Interagency Agreement EPA IAG-134(D)
Part A. Prepared for: Office of Research and Development, U.S.
Environmental Protection Agency, Washington, D.C. January 1975.
5. Written communication between William M. Vatavuk (U.S. Environmental
Protection Agency, Strategies and Air Standards Division, Economic
Analysis Branch, Research Triangle Park, North Carolina) and Sidney
Orem (Industrial Gas Cleaning Institute, Stamford, Connecticut).
Date: June 15, 1977.
6. Written communications between F.J. Rogers (Gypsum Association, Evanston,
Illinois) and William M. Vatavuk (U.S. Environmental Protection Agency,
Strategies and Air Standards Division, Economic Analysis Branch, Research
Triangle Park, North Carolina). Dates: April 29, May 11, and July 27, 1977
7. Written communication between William M. Vatavuk (U.S. Environmental
Protection Agency, Strategies and Air Standards Division, Economic
Analysis Branch, Research Triangle Park, North Carolina) and Curtis
Hamilton (Englehard Minerals and Chemicals, Attapulgas, Georgia).
Date: January 18, 1978.
8. Written communication between William M. Vatavuk (U.S. Environmental
Protection Agency, Strategies and Air Standards Division, Research
Triangle Park, North Carolina) and Ronald Zweben (Lear Siegler, Inc.,
Raleigh, North Carolina). Date: April 26, 1978.
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8.4 ECONOMIC IMPACT ASSESSMENT
8.4.1 Introduction
The non-metallic mineral industries crush, size, and in some cases
grind material extracted from the ground. The resultant output is generally
used as an intermediate product in such activities as highway or building
construction.
Although the 20 non-metallic mineral industries considered in this
economic impact assessment have similar production and marketing character-
istics, there are distinct differences among them. Although these minerals
must be extracted from the ground, the particular method used for extrac-
tion depends on the hardness of the mineral and the geological deposit in
which it is found. For example, stone must generally be extracted by blasting
with dynamite, while sand can be extracted with only power shovels. The
harder minerals are first broken with drop balls and transported by truck
to the crushing plant immediately following extraction.
As described in Section 3.2, most minerals then go through a number
of crushing steps in order to produce the requisite size material for the
purposes of the customer. This stage includes primary and secondary crushing
and, in some cases, tertiary crushing. In each crushing stage the material
is further reduced to a smaller size classification. These crushing stages
are important in producing material meeting the quality specifications of
the application. For some minerals; e.g., clay, dryers are interposed between
the various crushing stages to extract the moisture found in the material.
Other minerals such as stone and pumice do not require dryers, while still
other materials, such as sand, can be extracted and processed in a wet form.
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For many minerals the final crushing stage produces an output which
can be sold for various purposes; e.g., stone, and sand and gravel used
as a highway or concrete aggregate. Other materials must be further
reduced in size in a grinding mill before they are acceptable in product
applications; e.g., clay, which it to be expanded and gypsum used as a
retarder in cement production.
In short, non-metallic minerals are basically processed in the same
manner, but there are production distinctions which the following economic
impact analysis will address.
As Section 8.1 shows, non-metallic minerals have wide price differ-
entials. Even within a particular mineral, there are signifcant variations
in price depending on product application. The prices of non-metallic miner-
als range from $2/ton for sand gravel to $250/ton for high grade talc.
Most non-metallic minerals have regional markets. In general, the lower
the value of the mineral, the shorter is the distance that the material
travels to a customer. For example, stone, and sand and gravel, lower price
minerals, generally are not transported over 30 miles from the plant.
At this distance the f.o.b. plant price of the material is approximately
doubled by transportation costs. Therefore, transportation costs limit
the geographic area of competition for many non-metallic minerals and
competition between and among minerals is localized.
Ownership characteristics differ between the non-metallic minerals
industries. Stone quarrying and crushing is done primarily by privately
held companies which may have other business ventures requiring stone;
e.g., highway construction or concrete manufacturing. Gypsum, on the other
hand, is generally produced by diversified, publicly held companies in the
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building and construction materials industry who have integrated backwards to
the mine. Publicly held companies, diversified into many other activities,
though, are in general the largest producers in the industries.
In the analysis which follows, each new non-metallic mineral plant
will be assessed as if it stands alone; i.e., the plant is not associated
with any other business activity nor is it associated with any larger
parent company. This assumption has the effect of insulating the control
cost impact to the plant in question which must then support the control
cost without any assistance from other business activities or firms.
The impact which will be assessed in the effect of the incremental
cost of NSPS control on both:
• "Grassroots" new plants
• Expansions of existing plants.
The effect to be determined is the feasibility of these two investments,
and therefore, the potential for new and expanded plant construction with
the superimposed NSPS costs on each investment.
Incremental NSPS control costs are costs over and above those
control costs required to meet state implementation plan (SIP) standards.
Since each state has particulate emission control standards, any new plant
or reconstructed/modified plant would have to meet SIP standards in the
absence of the NSPS. Incremental costs are the difference between the costs
associated with NSPS control and SIP control. In this analysis SIP costs
are assumed to be non-existent, and therefore incremental costs are the
total of NSPS costs. Though SIP costs are not zero in the real world, this
assumption is used in order to provide a conservative analysis for evalua-
ting economic impacts.
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This section is organized in three parts. Section 8.4.2 will develop
the methodological procedure utilized to estimate the economic impact. Section
8.4.3 will present the findings of this analysis and Section 8.5 will show
the total industry costs of the promulgation of NSPS.
8.4.2 Methodology
This section will describe the methodology used to measure the eco-
nomic impact on the non-metallic mineral industries.
The economic impact is evaluated by developing model plants based on
historical characteristics in the non-metallic mineral industries. As will
be seen, these characteristics include production capabilities, asset
size and other financial characteristics. The models do not represent any
particular plant as any individual plant will differ in one or more of
these characteristics. The models are meant to provide an indication of
the degree of impact on all plants in a particular industry by incorporating
in the model the major characteristics prevailing in each segment of the
non-metallic mineral industry.
Two control cost models have been constructed for the 20 non-metallic
mineral industries, as seen in Section 6.
• Model 1 - those industries which generally only crush the
mineral
• Model 2 - those industries which generally both crush and
grind the mineral
Each industry has been further dissaggregated by typical model plant
sizes to account for size variations within each industry. Typical plant
sizes for each mineral are shown in Section 6. Although industry repre-
sentatives and equipment suppliers do not expect 9 Mg/hr (10 tph), 23 Mg/hr '
8-96
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(25 tph) and 68 Mg/hr (75 tph) plants in the crushed stone, and sand
and gravel industries to be constructed in the future, they were, neverthe-
less, analyzed because they have historically represented the majority of
plants in the industries.
Only minerals represented by model 2 are assumed to be in need of
expansion investment in the near future. Expansion will consist of a
4.5 Mg/hr (approximately 5 tph) and 9.1 Mg/hr (10 tph) grinding mills.
Expansion of existing plants represented by model 1 is not considered
because it is expected that they will need to invest in capital expansion
to meet increased demand only on a sporadic basis. Reconstruction/modifica-
tion of existing plants is also not considered; first, because routine
replacement of worn out equipment will not subject them to the NSPS; and
second because such replacement is expected to occur at a very slow pace
since the production life of most processing equipment is on the order of
20 to 30 years.
The first step in the analysis consisted of screening each of the
20 minerals by ranking the potential product price effects of the incremen-
tal control cost. Those minerals with the potentially highest product
price impact were then considered for further evaluation.
The next step in the analysis established the scenario under which
the plant would operate. This scenario consisted of four elements:
• the total of NSPS control costs were incremental
costs; i.e., that there are no SIP control costs
that a plant would have to incur in the absence of
NSPS control.
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• the production volume is constant throughout the
life of the project except for the crushed stone
plant where it is assumed that they operate at
50% of capacity for the first year.
• NSPS control cost pass through is limited by competition of
existing plants in the same industry which do not have to meet
the NSPS.
• the new plant operates as a separate business entity and cannot
expect to finance the control from another business activity or
parent firm.
Because of technical constraints in establishing a new quarrying
operation in the crushed stone industry, which constraints are not as
severe in the other industries, the crushed stone crushing plant is assumed
to operate at 50% of capacity during the first year.
The plant is assumed not to be dependent on any other business
venture. Therefore for new plants the NSPS control cost is not allocated
or spread over any operation except production of the affected facility
which is the new plant. Financing of the equipment can only be made from
the expected revenues of the new plant and from no other business venture.
For expanded plants a portion of the annualized control cost was assumed to
be absorbed by the existing plant which is being expanded.
Substitutability between many of the non-metallic minerals in many
product applications prevails in the market. Because of the variations in
control cost per ton between the minerals, the potential price increase of
any mineral should be expected to equal the cost pass through portion of
the nearest available mineral substitute with the lowest control cost per
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ton. If a new plant of one mineral was being constructed in the same
geographical competitive area as a new plant of another mineral and both
were perfect substitutes for each other, then the cost pass through would
likely be the control cost of the less affected mineral. A more conserva-
tive analysis is where a new plant of a mineral is constructed in the
same geographically competitive area as existing plants of the same mineral.
The existing plants would not experience any NSPS standard and therefore,
cost, and the new plant would have to compete with this existing plant.
The new plant would not be a major supplier of the mineral in the area and
would not be able to control the price. Therefore, this new plant would
have to completely absorb the control cost. But as demand grew for the
mineral, additional new plants would be required and/or, in the case of gypsum
and clay, older plants would have to expand to meet the increased demand.
This condition would bring an increasingly larger segment of the mineral
supply market under NSPS control. Therefore, it is likely that new plants
will be able to pass through the control cost gradually over the years. This
is reflected in our assumption that 25 percent of the control cost is passed
through every 4 years (alternatively every 4 years 25 percent less of
the cost is absorbed). This is the premise which is used in the succeeding
discounted cash flow (DCF) analysis.
Each plant size of each of the potentially significantly affected
minerals was then analyzed by using a discounted cash flow analysis (DCF).
DCF is an investment decision technique which provides information on
the economic feasibility of a potential capital investment. It measures
the discounted cash inflows over the life of the investment and compares
them to the discounted cash outflows. If the sum of the discounted cash
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inflows is equal to or greater than the sum of the discounted cash outflows,
the investment is feasible from the firm's point of view. If the sum of
the discounted cash inflows is less than the sum of the discounted cash
outflows, the investment is not feasible from the firm's point of view.
In order to take into consideration the time value of money, all cash
flows must be discounted to the present by use of an appropriate discount
factor. This is necessary to bring all cash flows to a comparable present
day basis for comparison.
Four data elements are required to complete the analysis:
• Expected life of the investment
• Cash flows to be discounted
• Weighted average cost of capital
• Total plant investment.
The expected life of the investment was taken to be 20 years although
the expected life of the major pieces of equipment can range from 20 to 30
years. The cash flows are discounted and summed over a 20 year period.
Any potential capital investment will generate cash flows in the
form of new earnings, and depreciation. These flows are discounted by the
weighted average cost of capital discount factors, summed, and compared to
capital outlays to determine the economic feasibility of the potential in-
vestment. In the analysis to be presented in the following section the
incremental NSPS control costs are superimposed on this model to determine
their effect on cash flow and the decision to invest in a new "grassroots"
or expanded plant for each size plant in each of the affected non-metallic
mineral industries identified for further analysis.
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The cash flows which are considered are:
1. Net earnings before interest and after tax.
2. Depreciation of the plant including control equipment.
3. Depletion.
4. Working capital recovery.
5. Plant and control equipment investment.
For each year cash inflows 1 through 4 are added (working capital
recovery occurs only at the end of the life of the investment, the 20th
year). This resultant annual sum is discounted and the annual discounted
sums are totalled over the 20 year period. This new sum is compared to
the discounted sum of the total investment including NSPS control invest-
ment. If the sum of the discounted cash inflows 1 through 4 is larger than
the discounted sum of cash outflow 5, the investment is economically
feasible even after the requirement of NSPS controls.
That an investment is found to be economically feasible does not
necessarily mean that the investment will be made by any individual firm.
Other forces or market concerns important to the company such as the desire
to diversify into other industries, or desire to expand through acquisitions
may preclude the new plant investment from being made.
The discount factors which are used to discount these flows are
determined by solving 1/(1 + i)n where i is the weighted average cost of
capital and n is the year from the beginning of the project. In this case
n is from 1 to 20. For each year of the 20 year investment span a different
discount factor is generated. Each year's discounted cash flow shows the
present value of that cash flow. The cost of capital is the weighted
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average financing expense of an investment that is financed partly through
debt and partly through equity.
Total plant investment was determined by the equipment needed for
quarrying, crushing, and, if appropriate, drying and grinding the mineral,
and added to the required NSPS control equipment capital cost developed in
Section 8.2 and working capital requirements.
8.4.2.1 Critical Elements
The following list provides the major critical elements of the
analysis for the significantly impacted industries:
• Control cost absorption is 25 percent less every 4 years.
• Maintenance expenditures over the life of the equipment
equal salvage value of the equipment.
• The profit rate for new plants is the same as existing
plants.
• All stationary plant equipment has a 20 year life with
the exception of rolling stock which has a 7 year life.
• 8,400 hours of operation per year is assumed for plants
with grinding capacity.
• Cost of debt capital is 3 percent above the prime rate of
7 percent in 1976.
• The total investment is financed 30 percent by debt and
70 percent by equity capital.
• Weighted average cost of capital is 11.8 percent.
• The debt financing maturity is 10 years for stationary
plants and control investment and 7 years for rolling
stock.
• Rolling stock is 77.7 percent of quarry investment.
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Maintenance expenditures are a cash outflow over the life of the
equipment while the salvage value of the equipment is a cash inflow at
the time of sale. No estimates of maintenance expenditures were found
during this analysis. Salvage value of equipment generally runs from 25
to 30 percent of the original cost. Since maintenance expenditures are
a negative cash flow and salvage value a positive cash flow and since
salvage value at the time of sale should be related to the amount of
maintenance put into the equipment it is assumed that they are equal
and counterbalance each other.
The profit rate on the new plant is assumed to be equal to an
existing plant although profit rates between a new and existing plant
will differ due to unique tax consequences and differences in technolo-
gical efficiencies. It is felt that these two effects counterbalance
each other sufficiently for the purpose of this analysis.
The plant has a useful life of 20 years. Equipment life varies among
the pieces of equipment used in the non-metallic mineral industry, but, on
average, the plant has a 20 year life. In the analysis some account has
been given to this aspect by separating "rolling stock" (mineral transport
vehicles) from stationary stock equipment and ascribing a 7 year life to
the rolling stock.
In those industries with grinding capacity, 8,400 hours of operation
is used to generate sales volume and revenue based on information supplied
by industry.
Industry representatives have stated that generally an investment
can be financed at 2 to 3% above the prime rate. A 3% above prime rate
was utilized to reflect a conservative analysis.
8-103
-------
A weighted average cost of capital for the mining industry as a whole
of 11.8% and debt/equity financing of 30/70% is given by Dr. Gerald
Pogue (Section 8.4.2.2). To the extent that particular non-metallic mineral
industries within the mining category experience a cost of capital of more
or less than 11.8%, the discounted cash flows will be different.
8.4.2.2 Data Sources
The following list provides the data sources for various aspects
of the analysis:
• Average Selling Price - Bureau of Mines
• Profit Rates - Robert Morris Associates
- Industry Representatives
- Annual Reports
• Working Capital - Robert Morris Associates
• Plant Investment - Barber-Green Co.
- Kennedy Von Saun Co.
- C. E. Raymond - Combustion Engineering
Inc.
• Cost of Debt Capital - Federal Reserve Bank
- Industry Representatives
• Cost of Capital, - "Estimation of the Cost of Capital for
Debt to Equity Ratio Major U.S. Industries with Application
to Pollution Control Investments", Dr.
Gerald A. Pogue, 1975.
• NSPS Control Costs, - Chapter 8.2
Sizes and Operating
Hours
8-104
-------
• Depreciation Schedules - Equipment Suppliers
• Investment Tax Credit, - Internal Revenue Code
Depletion Allowance
• Expected Life of - "Background Information
Equipment for the Non-Metallic Minerals
Industry," Vol. I, PEDCO Environ-
mental Specialists.
8.4.3 Screening Analysis
The first step in the analysis was to assess the effect on the 20
non-metallic mineral industries of NSPS control costs based on the ratio of
control cost per ton to price per ton. This ratio represents annualized cost
per ton as percent of average price. Table 8.37 presents the results of
this analysis.
Table 8.37 shows 25 entries because clay has been disaggregated into
6 distinct categories. For both those industries that fall under the Model
1 classification (crushing only) and Model 2 classification (crushing and
grinding) the impact is shown by dividing the annualized operating and
capital costs for control of the smallest size plant specified in Table
6.3 by the annual revenue of the mineral.
Because control costs per ton of mineral output are larger for the
smallest plant compared to the largest plant, this procedure inflates the
impact. Since large plants dominate the production in most industries,
average industry impact based on this ratio would be substantially lower.
Average industry impact is shown in section 8.5. Table 8.37 is not meant to
show industry impact but to be used as "worst case" screening method to
ascertain industries requiring further study.
8-105
-------
Table 8.37
RANK ORDER OF INDUSTRIES
Industry
Pumice
Sand and Gravel
Crushed Stone
Common Clay
Gypsum
Perlite
Fire Clay
Pyrites
Bentonite
Ball Clay
Salt
Barite
Feldspar
Fuller's Earth
Mica
Kaolin
Talc
Kyanite
Vermiculite
Fluorspar
Diatomite
Sodium Compounds
Boron
Potash
Gi Isoni te
WITH HIGHEST CONTROL COST IMPACT
Rank
1
2
3
4
5
6
7
8
9
10
11
12
13
14
14
14
17
18
18
18
18
22
23
23
25
Control Cost/Ton
Price/Ton! U
28.0%
15.8
13.4 Candidates
11.7 for further
5.0 evaluation
4.1
2.0
1.5
1.4
1.3
1.2
1.1
1.1
.6
.6
.6
.4
.3
.3
.3
.3
.2
.1
.1
-(2)
(l)Based on smallest model size in industry.
(2)No price available - only 1 company producing approximately
100,000 tpy.
8-106
-------
Any industry where the per ton control cost was larger than 2% of the average
price was considered to be potentially significantly impacted and worthy of
further evaluation. Two percent was taken to be the cut-off point because
this rate, even in the worst case situations, is considerably lower than
the 5% industry average rate which is the EPA guideline for assessing major
economic impact. The minerals considered to be potentially significantly
impacted are pumice, sand and gravel, crushed stone, common clay, gypsum,
and perlite.
Perlite, gypsum and pumice have three stationary model plant -sizes:
9, 23 and 68 Mg/hr (10, 25 and 75 tph). Common clay has four; 9, 23, 68
and 136 Mg/hr (10, 25, 75 and 150 tph). Both sand and gravel, and crushed
stone have six stationary model plant sizes, 9, 23, 68, 136, 272 and 544
Mg/hr (10, 25, 75, 150, 300 and 600 tph). In addition sand and gravel, and
crushed stone have a portable 181 Mg/hr (200 tph) model plant.
Each of the six remaining potentially significantly affected miner-
als were then compared on the basis of relative prices, and the effect of
control costs on relative prices of the minerals, taking into account the
product substitutability among them. This analysis showed that the "worst
case" situation was a new plant of any mineral competing with an existing
plant of the same mineral. For each mineral, a baseline relative price was
computed. This relative price was the ratio of the price of each mineral
to the price of each of the other minerals prior to NSPS control costs.
This baseline relative price ratio was then compared to the "worst case"
situation after the imposition of control costs, assuming all control costs
were passed through. The "worst case" situation was the smallest size
plant of any mineral compared to the largest size plant of the remaining
8-107
-------
minerals since control costs per ton of output are larger for smaller
plants. A decline in this ratio, price of other minerals after control
divided by the price of this mineral after control, indicates that other
minerals are becoming less expensive relative to this mineral and that
demand should significantly shift away from this mineral if the cross-
elasticity of demand is high.1 Cross-elasticity of demand is dependent on
the minerals having acceptable substitutability potential. The substitutability
potential was evaluated by comparing the mineral of interest to the two
minerals having the largest changes in relative prices. In each case sub-
stitutability potential was rated only low to moderate because of the
product quality differences between the minerals and the geographical
separation of deposits of different minerals. For this reason the more
conservative scenario, a new plant of any mineral competing with an existing
plant of the same mineral, was employed in the analysis.
8.4.4 Plant Investment
Grassroots Plants
Investment costs were gathered for quarrying, crushing, and where
appropriate, drying and grinding equipment from equipment suppliers.
Tables 8.38 and 8.39 show the total investment costs for each size plant
studied in each industry. For all plant sizes smaller than 136 Mg/hr (150
tph), quarrying and crushing plant costs were derived by use of the engineer-
ing 0.6 power capacity rule. For the quarrying operation, rolling stock was
Cross-eleasticity of demand is the percentage change in the quantity of
one product divided by the percentage change in price of another
product.
8-108
-------
Table 8.38
PLANT INVESTMENT COSTS1
(in thousands of dollars)
Size
Mg/hr (tph)
9 23 68 136 272 544 P1812
Industry (10) (25) (75) (150) (300) (600) (P200)
Pumice $269.9 $ 410.4 $ 740.3 N.A. N.A. N.A. N.A.
Sand & Gravel 236.9 374.4 693.2 $1,034.6 $2,035.1 $3,986.7 $1,702.7
Crushed Stone 251.1 399.6 742.9 1,139.0 2,188.6 4,291.4 1,804.4
Common Clay 817.4 1,282.3 2,160.4 3,118.1 N.A. N.A. N.A.
Gypsum 664.9 1,058.3 1,850.2 N.A. N.A. N.A. N.A.
Perlite 555.3 822.2 1,654.1 N.A. N.A. N.A. N.A.
Includes NSPS control capital costs and working capital.
2
Portable plant.
>A'Not Applicable because plants of this size are not likely to be
constructed in the absence of a NSPS.
8-109
-------
Table 8.39
EXPANSION INVESTMENT COSTSl
Industry
(in thousands of dollars)
Si zs
Mg/hr (tph)
4.5
(5)
9
(10)
Common Clay
Gypsum
$288.1
292.9
$421.1
430.7
Includes NSPS control costs and working capital
8-110
-------
separated from stationary stock by factoring total quarry investment cost
by 0.777. All plant investment costs were deflated to fourth quarter,
1976 prices in order to make investment consistent with the derivation of
sales revenue which is based on fourth quarter, 1976 average selling
prices. The investment deflator was calculated from the Chemical Engineer-
ing equipment cost index.
Once total plant investment was calculated and separated into sta-
tionary plant equipment and rolling stock, NSPS control cost investment
and working capital were added to stationary stock investment. The debt
portion of the stationary stock investment was derived by using a 0.3 factor
specified by the Dr. Gerald Pogue study; i.e., 30% of investment financed
by the bank and 70% from the investor's own funds, equity. Bank financing
for stationary stock debt was taken by 10%, 10 years, giving a capital
recovery factor (CRF) of 0.16275. These industries are usually able to
receive financing at 2 to 3% above the prime rate. In 1976 the prime
rate was approximately 7%. The debt portion of rolling stone investment
was also established by using a 0.3 factor. The rolling stock was assumed
to be financed at 10% over the useful life of the stock, 7 years. The CRF
is 0.20541. Subsequent purchase of new rolling stock to replace original
rolling stock was assumed to occur at the same price. For both stationary
and rolling stock, the annual principal and interest payment were calculated
Derived from "The Crushed Stone Industry: Industry Characterization
and Alternative Emission Control Systems", Arthur D. Little, Inc.
where rolling stock equals 77.7% of total quarry plant costs.
8-111
-------
Expansion Plants
Investment costs for expansions consisted of 4.5 Mg/hr (5 tph) and 9 Mg/hr
(10 tph) grinding mill costs for the clay and gypsum industries only. These
investment costs are shown in Table 8.39. Debt financing was 30% of total
investment at 10% over 10 years.
8.4.5 Discounted Cash Flow Analysis
Table 8.40 which shows an analysis for construction of a new 136 Mg/hr
(150 tph) crushed stone plant is an example of the data sheets which were
developed for each of the plant sizes for each of the six potentially
significantly impacted industries. The steps in the DCF analysis will be
described below using this example and referring to row entries in Table 8.40.
• Row 1, revenue, was generated by multiplying hours of operation
by tons per hour of output and by the average F.O.B. plant sell-
ing price of the output. This revenue estimate was assumed con-
stant for each year of the life of the investment. For stationary
crushed stone plants, the plant was taken to operate at 50% of
capacity the first year as related by industry representatives.
Control equipment was assumed to be operating at TOO percent,
and therefore control operating costs are 100 percent.
• Row 3, interest including control, was determined by calcula-
ting the principal and interest repayment schedule for the
plant investment without control investment.
• Row 4, earnings before interest and tax, was derived by multi-
plying revenue by the before tax profit rate of row 2 and
adding back the interest of row 3.
8-112
-------
TABLE 8.40 DISCOUNTED CASH FLOW ANALYSES CRUSHED STONE PLANT
136 Mg/hr (150 tph) (IN THOUSANDS OF DOLLARS)
00
(__i
(__1
u>
1 te»e*ue J
2 profit rate before ta»
3 Interest exclwltn*} control
4 Ear*f*fS before interest
and tax
5 Aung* H zed control cost
C Control Cost absorbed
7 Control Interest
8 Het earnings before Interest
and after control
9 Federal tax liability
(also considering Interest)
10 InvestBent tax credit
11 Federal tax liability
after credit
12 Hiniaue tax
13 State tax
14 Bet earnings before Interest
after credit, control & tax
15 Depreciation of
stationary stocfc
16 Depreciation of
rolling stock
17 Depreciation of
control equipment
IB Depletion Si
1ft Un^& inn mi 4 fa 1 rPfGVPrv
15 IfOrK i fly Capl vtt i f t!v-wĄCi j
20 Cash Inflow
21 Discount factor
22 Discounted cult inflow
23 Cas» o«tflo« 1111.0
24 Discounted cash
oitflnr 1111. C
1177
iJbZ.i
9.01
29.7
C1.4
27.8
Ml
3.7
37.1
.8
.8
0
0
.2
'37.1
64.1
45.6
12.2
2.
161.
.8945
144.
1971
J/fli.!)
9.01
27.4
98.9
27.5
All
3.4
66.8
7.4
7.4
0
1.2
1.8
63.8
64.1
45.6
12.2
16.
203.7
.80
163.
1979
J565.5
9.01
24.9
88.4
27.2
HI
3.1
64.3
7 .5
7.5
0
1.2
1.8
61.3
64.1
45.6
12.2
18.2
201.4
.7156
144.1
1980
1785.5
9. OX
22.2
85.7
26-9
*11
2.8
61.6
7.6
7,6
1)
1.2
1.8
58.6
64.1
45.6
12.2
18.4
198.9
.64
127.3
1981
5,705.5
9.01
18.7
12.2
26. 6
20.
2.5
64.7
91
. i
9.1
0
1.7
2.2
60. 8
64.1
45.6
12.2
21.7
204.4
.5725
117.
1982
J70S.5 i
?.n
.8
79.3
26.2
19.7
2.1
61.7
9 1
9^1
0
1.7
2.2
57.8
64.1
45.6
12.2
21.9
201,6
.512
103.2
1983
9.01
12.1
75.6
25.8
19.4
1.7
57.9
9 2
9^2
3
1.7
2.2
54.
64.1
45.6
12.2
Z2.0
197.9
.458
90.6
1984
l7.-Jf
81.2
25.4
19.1
1.3
63.4
9 3
9^3
0
1 .7
2.2
59.5
6t.l
45.6
12.2
22.2
203.6
,4097
83.4
326
131
1985 19S6 1987
9.01 9.01 9.01
14.2 10,4 6,3
77.7 73.9 69.8
24.9 24-4 11,9
12.5 12,2 0
.8 .3 0
66. 62. 69.8
110 111 165
n'o n!i 9^9
0 0 6.6
2.3 2.3 2.3
2-6 2.6 3.2
61.1 57.1 57.7 4
64.1 64.1 0
45-6 45,6 45.6 '
12.2 12.2 0
25.5 25.6 31.8 3
208. S 204.6 135.1
.3665 .3278 .2931
76.4 67,1 39.7
'»« '.'.a' 1990
&/05.5 1/05.5 -,„, E
9.01 9.01 S7Ł515
4.5 3.4 f-«»
68 66.9
11.9 11.9 65-3
0 0 «„'
0 0 J
68 66.9 65 3
17 17 .
1 / I/ 37
0 0 0
17 17 ,7
2.3 2.3 2.3
3.2 3.2 3.2
5-5 44.4 42.8
000
15-6 45. 6 <5'6
00°
1-8 31.8 31.8
122.9 121.8 120 2
.2622 .2346 . ?09«
32.2 28.5 25 2
1991
S705.S
9.01
9.6
73.1
U69
0
73.1
17
17
0
3.3
3.2
66.6
0
45.6
0
31.8
144
.1877
27
326
60
1992
$705.5
J:P
72.1
11.9
0
0
72.1
17
15.0
2
3.3
3.2
63.6
0
45.6
0
31.8
141
.1679
23.7
1993
$705- 5
??r
71
11.9
0
0
71
17
0
17
2.2
3.2
48.6
0
45.6
0
31.8
126
.1501
18.9
19*4
5705. S
9.0t
6.3
69.8
11.9
0
0
69. 8
17
0
17
2.2
3.2
47.4
0
45. 6
0
31.8
124.8
.1343
16.8
1995
S705. 5
9-Ot
4.5
68
11.9
0
0
68
17
0
17
2.1
3.2
45.6
0
45.6
0
31.8
123
.1201
14.8
1996
$705.5
9.0%
3.4
66.9
11.9
0
0
66.9
17
0
17
2.2
3.2
44.5
0
45.6
0
31,8
28.2
150.1
.1074
16.1
Total Discounted Ush i,f|o» 1359
Total Discounted Cash Outflow 1302.0
8-110
-------
Row 5 shows the NSPS annualized control costs for each year.
Since depreciation for control equipment was taken to be
straight line over 10 years, the years from 1987 onward show
only annual operating costs.
Row 6, control cost absorbed, reflects the scenario mentioned
in Section 8.42, methodology. For the first 4 years all
control cost is assumed to be absorbed because the plant is
competing with existing established plants which have no NSPS
costs. Therefore, the new plant must absorb the entire cost.
In the years 1981 to 1985 the plants must absorb 75% of the
cost and can pass through 25% because other new plants are
being established. New plants must, then, meet NSPS costs.
For each succeeding 4 year period, the plant absorbs 25%
less of the original cost. Since in the year 1987 total
operating costs are less than control cost absorbed in 1986, all
operating costs are assumed to be passed through in the years
from 1987 to 1996.
Row 7, control interest, was derived by calculating the prin-
cipal and interest repayment schedule for the NSPS control
investment.
The increased revenue from cost pass through is not shown since we
are only interested in the effect of cost absorption on net earnings,
8-114
-------
Row 8, net earnings before interest and after control, shows
the effect of NSPS absorbed control costs on the earnings
potential of the plant. Absorbed control costs are subtracted
from Row 4 and control of interest of Row 7 is added back. Adding
back of interest is required in the model because the discount
factors taken into consideration the repayment of the loan.
Row 9, federal tax liability, is derived by multiplying net
earnings after control by the appropriate marginal tax rates.
Row 10, investment tax credit, considers the effect of the 10%
investment tax credit on the tax liability of the plant.
(The investment tax credit can be carried forward 7 years or
until 10% of the investment is credited, whichever comes first.
The tax credit cannot be greater than tax liability and for tax
liabilities over $25,000 the credit is calculated as $25,000
plus 50% of the liability over $25,000. For example, in year
1977 tax liability is $800, therefore, the credit is $800 since
the credit cannot be greater than tax liability. In year 1978
the same reasoning applies. If tax liability had been $30,000,
then the credit would have been $25,000 + (0.5) $5,000 or $27,500.
Row 11, federal tax liability after credit, is tax liability
minus the investment tax credit.
Row 12, minimum tax, shows the 15% minimum tax on tax prefer-
ence items. In this analysis the only tax preference item is
the depletion allowance.
Row 13, state tax, is assumed to be 5% of net earnings. The
5% rate is the most common rate of the majority of states.
Row 14, net earnings before interest after credit, control and
tax, shows the effect of NSPS control costs and the investment
tax credit on after tax earnings. It is derived by subtracting
8-115
-------
federal tax liability after credit, the minimum tax and state
tax, from Row 8. As can be seen, this figure varies over the
years as control cost absorbed is lowered and as the original
tax credit is exhausted and credit for new rolling stock is
taken and exhausted and as interest payments are reduced. Net
earnings before interest after credit, control and tax is the
first category of our cash flow. All succeeding categories
also affect cash flow.
Row 15 is added to Row 14 and represents depreciation of
stationary stock, depreciated straight line over 10 years.
Row 16, depreciation of rolling stock, is added to the above.
This depreciation, which is taken over 7 years, comes into
play in later years as new rolling stock is purchased in
years 1984 and 1991.
Row 17, depreciation of control equipment, is taken over 10
years and added to the other depreciable equipment.
Row 18, depletion, is added to the cash flow since all of
these industries are in the mining classification and deple-
tion allowance increases cash flow.
(Depletion can be taken in one of two ways: cost depletion or
percentage depletion. Cost depletion is dependent on the cost
basis of the land, amount of mineral mined and estimated amount
of mineral reserves. Percentage depletion is based on a
specified percentage of sales revenue, the percentage differs
by industry, to a maximum of 50% of taxable income before
depletion is counted. Cost depletion cannot be calculated here
because it is site specific; i.e., dependent on the cost of the
property and reserves on the property. In any case, most
companies generally use percentage depletion. In the example
depletion is shown as $2,000 in 1977. The percentage depletion
allowance for stone is 5%. For 1977 this amounts to $17,600,
but the plant can only use $2,000 because of the 50% taxable
income limit.)
8-116
-------
• Row 19, working capital recovery, shows that at the end of the
project working capital is recovered. Working capital is taken
to be 4% of revenue.
• Row 20, cash inflow, shows for each year the expected total of
the above cash flow categories, and is the amount which must be
discounted to the present by the discount factors shown in row
21. Row 22 is the result; i.e., Row 20 multiplied by Row 21.
• Row 23, cash outflow, shows the investment expenditures necessary
to establish the operation. Investment of $1.1 million is made
initially and subsequent rolling stock investment is made in
years 1984 and 1991. These cash outflows are discounted by the
appropriate discount factors of Row 21. Row 24 is the result.
The weighted average cost of capital of 11.8% generates the discount
factor for each year of the 20 year period. These factors show the present
value of a dollar of future cash flow for each future year. After the
annual cash flows are discounted, they are summed to derive the present
value of the cash inflows over the life of the project. This cash inflow
is then compared to the cash outflow, which is the present value of the
total investment. In this example the present value of net cash inflows
is greater than the present value of cash outflows, so that an investment
in a 136 Mg/hr (150 tph) crushed stone plant with NSPS controls attached is
profitable at a weighted average cost of capital of 11.8%.
8.4.6 Findings
Table 8.41 presents the results of this analysis for each size plant
of the potentially significantly affected industries. For the 9 and 23
Mg/hr (10 and 25 tph) sand and gravel, and crushed stone plants the DCF
8-117
-------
Table 8.41
SUMMARY OF DCF RESULTS
Grassroots Plants
Investment Decision
Size - Mg/hr (tons per hour)
9 23 H58 136 272544 P1811
Industry (10) (25) (75) (150) (300) (600) (P 200)
Pumice NF F F N.A. N.A. N.A. N.A.
Sand & Gravel NF2 NF2 A2 F F F F
Crushed Stone NF2 NF2 A2 F F F F
Common Clay NF A F F N.A. N.A. N.A.
Gypsum A F F N.A N.A. N.A. N.A.
Perlite F F F N.A. N.A. N.A. N.A.
1. Portable plant
2. Equipment suppliers and industry representatives do not expect
plants of this size to be constructed even in the absence of
NSPS.
Key: F - economically feasible to construct
NF - not economically feasible to construct
A - ambiguous
N.A. - not applicable because plants of this size are not
likely to be constructed in the absence of NSPS.
8-118
-------
analysis indicates that the investment is not economically feasible. The
same result holds for the 9 Mg/hr (10 tph) common clay plant.
For the 68 Mg/hr (75 tph) sand and gravel, and crushed stone plants, the
23 Mg/hr (25 tph) common clay plant and the 9 Mg/hr (10 tph) gypsum plant, the
DCF analysis showed negative discounted cash flows ranging from less than 2%
of total investment for common clay to approximately 16% for gypsum. An
internal rate of return (IRR) was calculated for each of these four model
plants. The internal rate of return is that rate which makes the discounted
cash outflow. The IRR varied from approximately 8.5% for gypsum to slightly
less than 10% for common clay. Since the net discounted cash flows were only
slightly negative; i.e., the IRR was fairly close to 11.8% cost of capital,
small changes in the parameters of the worst case analysis would produce
positive net discounted cash flows. For this reason the 68 Mg/hr (75 tph)
sand and gravel, and crushed stone plants, the 23 Mg/hr (25 tph) common clay
plant and the 9 Mg/hr (10 tph) gypsum plant are determined to be economically
feasible to construct, if the conservative assumptions used throughout this
report are relaxed.
Table 8.42 shows the results of the DCF analysis on expansions of 4.5
and 9 Mg/hr (5 and 10 tph) grinding capacity in the common clay and gypsum
industries. In the analysis the expansion was assumed to take place in the
smallest size existing plant; i.e., 9 Mg/hr (10 tph), in order to provide a
"worst case" situation. The control costs were assumed to be spread over both
new and existing output based on the ratio of new to existing output. As is
shown in Table 8.42, all expansion size plants except the 4.5 Mg/hr (5 tph)
common clay plant were determined to be economically feasible to construct.
8-119
-------
Table 8-42
SUMMARY OF DCF RESULTS
Expansions
Investment Decison
Size
Mg/hr (tph)
4.5 9
INDUSTRY (5) (10)
Common Clay A
Gypsum F
Key: F - economically feasible to construct
A - ambiguous
8-120
-------
It should be kept in mind that because an investment is found to be
economically feasible from a DCF analysis it does not necessarily mean
that the investment will, in fact, be made by a company.
NSPS control costs will not significantly affect those non-
metallic mineral industries for which a DCF analysis was not performed.
As seen in Table 8.37 the greatest potential NSPS control cost absorp-
tion is less than or equal to 2% of product price, since these non-metallic
minerals all have a higher product price than those non-metallic minerals
for which a DCF analysis was performed. The process economics are similar
for both industries for which a DCF analysis was performed and for which a
DCF analysis was not performed. Since the DCF analysis was favorable for
industries whose potential control cost absorption was equal to or greater
than 4% of product price, the DCF analysis will be favorable for industries
where this ratio was equal to or less than 2%. For this reason a DCF
analysis performed on each of those 19 non-metallic minerals excluded from
further consideration in Table 8.37 would show an economically feasible
investment decision for all size new plants.
Crushing and grinding facilities are also a portion of production
operations whose final output is not a specific type of non-metallic
mineral, such as at lime and power plants; i.e, crushing and grinding are
intermediate processes in these industries.
These intermediate processing facilities are usually constructed
by firms in the above mentioned industries because the need for the
non-metallic mineral is large enough to support such a facility. Such
8-121
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intermediate facilities can produce the requisite size mineral at a
lower cost to the firm than can be attained from buying the mineral from an
independent producer. Consequently, some cost increase could be sustained by
intermediate processing facilities and still permit them to be competitive
with firms that purchase the requisite size material from independent
producers. Furthermore, the intermediate processor is able to spread
the incremental cost over a final product whose selling price is larger
than that of the non-metallic mineral input, and, thus can more readily
pass on these costs. Finally, because of their affiliation with larger
companies, these facilities would tend to have a lower cost of capital.
Therefore, the investment decision resulting from the DCF analysis for
various plant sizes in the non-metallic mineral industries per se would
likely hold for intermediate processing facilities (that are part of
other facilities).
8.5 POTENTIAL SOCIO-ECONOMIC AND INFLATIONARY IMPACTS
8.5.1 Industry Cost Totals
Table 8.43 presents the upper limit to the number of typical new
plants which will be constructed in each industry in each of 5 years
based on projected industry growth and the typical plant size in each
industry. The projections of new plants required is based on growth from
1975 production statistics and assumes that 1975 production equals capacity.
To the extent that actual production was lower than capacity production,
the number of estimated typical size plants required each year will be
lower. Therefore required total industry annualized control costs will be
lower.
8-122
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Table 8.44 indicates the cumulative annualized industry capital and
operating costs in 1976 dollars to meet the NSPS standard. The totals are
derived by multiplying the estimated number of typical plants to be con-
structed in each year by the annualized control costs for these size plants.
As can be seen, the crushed stone industry would have the largest annualized
costs by the fifth year, $19.2 million.
Table 8.45 shows the average annualized cost per ton of output in the
fifth year after control. These figures are based on the estimated comu-
lative annualized costs in the fifth year, Table 8.44, divided by the estimated
total industry production in the fifth year. Kyanite shows the largest
industry cost per ton of $0.137 per ton. Table 8.45 also shows that control
cost per ton as a percent of price per ton is highest for pumice, 1.7%.
New regulations shall be considered a major action if "additional
annualized cost of compliance, including capital charges (interest and
depreciation), will total $100 million (i) within any one of the first
5 years of implementation, or (ii) if applicable, within any calendar
year up to the date by which the law requires attainment of the relevant
pollution standard," or "total additional cost of production of any major
industry product or service will exceed 5 percent of the selling price of
the product." Total industry annualized control cost in the fifth year
after promulgation of NSPS and control cost as a percent of selling price
are lower than the guidelines set for these measures of $100 million
for annualized capital and operating expense and 5 percent, respectively.
8-123
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TABLE 8.43 ESTIMATED NUMBER OF TYPICAL NEW PLANTS REQUIRED TO
MEET PROJECTED PRODUCTION*
_ _ . - - - • • -T- - • • — ,.'.,-,
Industry
Pumice
Sand and Gravel
Crushed Stone
Common Clay
Gyps irn
Perlite
Rock Salt
Sodium Compounds
Potash
Talc
Barite
Boron
Flourspar
Pyrites
Feldspar
Diatomite
Vermiculite
Mica
Kyanite
Natural asphalt
& Related Vitumens
Typical
size
(Mg/hr)
9
272
272
23
23
23
68
23
272
9
9
272
9
23
9
23
68
9
9
9
Growth
rate
(%)
3.5
1.0
4.0
3.5
2.0
4.0
2.0
2.5
30
4.0
2.2
5.0
3.0
4.0**
4.0
5.5
4.0
4.0
6.0
_
1980 1981
2 2
14 14
72 75
10 10
1 1
1
2 2
1
-
1
-
-
-
-
-
-
-
-
-
_ _
1982
2
14
78
10
1
1
3
1
-
1
1
-
-
-
1
1
-
-
-
_
1983 1984
2 2
14 15
81 85
11 11
1 1
1
3 3
1
-
1
-
-
1
-
-
-
1
1
1
_ _
K
Whenever the projected production for a given year was not
enough to justify the building of a new typical size plant, no
new plants were assumed to be built.
**
Assumed 4 percent.
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TABLE 8.44 ANNUALIZED CAPITAL AND OPERATING CONTROL
COSTS FOR NEW PLANT CONSTRUCTION
Industry
1980
Pumice 42.4
Sand and gravel 777
Crushed stone 3,996
Common clay 234
Gypsum 23.4
Perlite
Rock salt 46.8
Sodium compounds
Potash
Talc
Barite
Boron
Fluorspar
Pyrites
Feldspar
Diatomite
Vermiculite
Mica
Kyanite
Natural asphalt &
related bitumens
TOTAL
Annualized
(in thousands of
1981
84.8
1,554
8,158.5
468
46.8
16
93.6
23.4
-
21.2
-
-
-
-
-
-
-
-
-
-
1982
127.2
2,331
12,487.5
702
70.2
32
163.8
46.8
-
424
21.2
-
-
-
21.2
23.4
-
-
-
-
cost
dollars)
1983
169.6
3,108
16,983
959.4
93.6
32
234
70.2
-
42.4
21.2
-
-
-
21.2
23.4
-
-
-
-
1984
212.0
3,940.5
21,700.5
1,216.8
117
48
304.2
70.2
-
63.6
21.2
-
21.2
-
21.2
23.4
23.4
21.2
21.2
-
27,825.6
8-125
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TABLE 8.45 ANNUALIZED CONTROL COST PER TON OF INDUSTRY
OUTPUT IN 5TH YEAR AND CONTROL COST AS PER-
CENT OF SELLING PRICE
Industry
Control cost
per ton
($)
Annualized cost
1984 tonnage x
price/ton*
Pumice
Sand and gravel
Crushed stone
Common clay
Gypsum
Perlite
Rock salt
Sodium compounds
Potash
Talc
Barite
Boron
Fluorspar
Pyrites
Feldspar
Diatomite
Vermiculite
Mica
Kyanite
Natural asphalt &
related bitumens
0.043
0.005
0.018
0.019
0.01
0.051
0.017
0.012
-
0.049
0.014
-
0.123
-
0.023
0.026
0.052
0.116
0.137
-
1.7 %
0.2
0.8
0.9
0.2
0.3
0.1
0.03
-
0.1
0.1
-
0.1
-
0.1
0.03
0.1
0.3
0.2
-
K
Based on 1976 average F.O.B. mine selling price.
8-126
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9. RATIONALE
9.1 SELECTION OF SOURCE FOR CONTROL
Section 111 of the Clean Air Act requires establishment of standards
of performance for stationary sources that cause or contribute significantly
to air pollution which may reasonably be anticipated to endanger public
health or welfare. Also, under Section 109 of the Act, particulate matter
has been designated as a criteria pollutant for which National Ambient Air
Quality Standards have been set.
By the year 1985, new, modified, and reconstructed non-metallic mineral
processing plants would cause annual nationwide particulate matter emissions
to increase by about 45,000 megagrams per year (50,000 tons per year) if they
comply with typical State process weight regulations. In a study performed
for EPA by Argonne National Laboratory in which significant sources of
particulate matter were identified and ranked in order of total emissions,
several non-metallic mineral processing industries ranked in the top 50
percent of industries emitting particulate matter. This study was used to
establish a priority list for setting standards for major sources of
particulate matter and the other criteria pollutants. Non-metallic
mineral processing plants were ranked 13th among 58 source categories. In
addition, an uncontrolled 9.1 Mg/hr (10 ton/hr) crushing plant would emit 100
megagrams (110 tons) of particulate matter per year, thereby becoming classi-
fied as a "major emitting facility" under section 302 of the Clean Air Act.
The production of non-metallic minerals is projected to increase at
compounded annual growth rates of up to 6 percent through the year 1985
9-1
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depending on mineral type. In 1975, over 1.6 billion megagrams (1.8 billion
tons) of minerals were produced; by 1985 this production is expected to in-
crease to over 2.0 billion megagrams (2.3 billion tons) per year. Geographi-
cally, the non-metallic minerals industry is highly dispersed, with plants
processing at least one of the 20 non-metallic minerals located in all States.
The 20 minerals covered by the proposed standards were selected on the
basis of production tonnage rather than on the basis of any health or welfare
considerations as compared to other minerals. They are the top 20, excluding
minerals for which standards have already been established or are being
developed. Also excluded were minerals, such as sulfur, bromine, peat, and
slag, with production processes which are not typical for most minerals.
Non-metallic mineral processing plants are significant contributors
to total nationwide emissions of particulate matter and have been selected
for inclusion under standards of performance for new sources.
9.2 SELECTION OF POLLUTANT AND AFFECTED FACILITIES
Particulate matter is the only pollutant released from the affected
facilities and therefore, is the only pollutant covered by the proposed
standards. The affected facility is defined as the entire mineral pro-
cessing plant including the following pieces of process equipment: crushers,
grinding mills (including air separators, classifiers, and conveying
systems), screening operations, bucket elevators, conveyor transfer
points, bagging operations, storage bins, and fine product (less than
20-mesh) truck and railcar loading stations. Portable plants are included as
affected facilities because, other than being mounted on wheels, they are
similar to stationary plants and should be able to use the same emission
control techniques. Facilities already covered by standards of performance
9-2
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for other source categories would not be covered by the proposed standards.
The proposed standards would apply, however, to process equipment at
lime plants, power plants, steel mills, and other source categories
which operate separate mineral processing plants. Process equipment at
asphalt concrete plants and Portland cement plants would be subject to
the standards if, in the process, they precede equipment already covered
by other standards of performance.
Truck and railcar loading stations are included process operations when
fine product material is loaded. The term "fine product" refers to any
material which is less than 20 mesh. Fine products are generally loaded
into tank trucks or enclosed railroad cars by gravity feeding through plastic
or fabric sleeves. As the material is fed into the vehicle, dust-laden air
is forced out through another opening as the material displaces the air.
Thus, fine product loading is generally a partially enclosed operation
amenable to air pollution control. Loading of coarser material, however, is
generally done by loading the material from a stockpile or storage bin to
an open truck or railcar and is not an enclosed operation amenable to air
pollution control. Local exhaust systems to control dust emissions from
bin load-out operations are impractical because of the variability in the
bed size of the trucks loaded. Attempts to ventilate the entire bin
load-out area have been ineffective due to the large air volumes required.
Therefore, only fine product loading is amenable to the same emission
control technique as the other process operations included under the
proposed standards.
The process operations included under the proposed standards were
selected because they are significant individual sources of particulate
9-3
-------
matter emissions at non-metallic mineral processing plants and because
they are amenable to air pollution control.
Process operations common to most plants which are not covered by the
proposed standards include drilling, blasting, loading at the mine, hauling,
stockpiling, conveying (other than transfer points), and windblown dust from
stockpiles, roads, and plant yards. These operations are not included
because they are not amenable to air pollution control using the emission
control techniques upon which the proposed standards are based. They are,
however, significant sources of particulate matter emissions. Methods for
controlling emissions from these operations are discussed in the document
entitled "Air Pollutant Control Techniques for the Crushed and Broken Stone
Industry" available from the EPA Library (MD-35), Research Triangle Park,
North Carolina 27711, telephone number (919) 541-2777.
Each process operation controlled under the standards could have been
defined as an affected facility. This option was considered and rejected
because of the adverse impact it would have on existing plants. Equipment
life varies among the process operations constituting a non-metallic
mineral processing facility. On the average, process equipment has a 20
year life. Assuming a rectangular distribution in the age of existing
equipment, 5 percent of existing equipment would have to be replaced
each year. As a result, specification of each piece of process equipment
as an affected facility could impact significantly upon many existing
plants in a relatively short time period after proposal of the standards.
The intent of the standards is not to require retrofit of existing sources
but rather to require installation of air pollution control equipment on
new sources when they are being constructed. Therefore, in order to
9-4
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minimize the impact on existing plants, the entire plant has been designated
the affected facility.
9.3 SELECTION OF THE BEST SYSTEM OF EMISSION REDUCTION
Section 111 of the Clean Air Act requires that standards of performance
reflect the degree of emission limitation achievable through "application of
the best system of continuous emission reduction which (taking into con-
sideration the cost of achieving such emission reduction, and any nonair
quality health and environmental impact and energy requirements) has been
adequately demonstrated."
Methods currently in use to reduce particulate matter emissions at
non-metallic mineral processing plants include wet dust suppression, dry
collection, and a combination of the two. Wet dust suppression consists of
spraying the materials with a fine mist of water causing fine particulate
matter to adhere to the surface of the larger materials rather than becoming
airborne. Dry collection involves hooding or enclosing dust-producing points,
collecting the dust generated, and passing the dust-laden air through a
collection device. Combination systems use both methods at different
stages throughout the processing plant. In addition to these control
techniques, the use of enclosed structures to house process equipment may
also be effective in preventing particulate matter emissions from reaching
the atmosphere.
In a wet dust suppression system, water (with or without a wetting
agent) is sprayed on the materials at critical dust-producing points in the
process flow. This method has been used on a wide variety of materials
including limestone, traprock, granite, shale, dolomite, and sand and
gravel. It can generally be considered to have an application to materials
handled through crushing operations.
9-5
-------
Wet dust suppression cannot be used in some cases, however, since the
moisture may interfere with further processing such as screening or grinding
where "blinding" problems may occur. In addition, the thermal capacity of
the dryers which are used in some processing steps may limit the amount of
water that can be sprayed onto the materials. The addition of water at
processing steps after the drying operation is not feasible for products sold
in dry form and other means of emission control must be used. Where the
materials processed contain a high percentage of fines, such as the product
from a hammer mill, wet dust suppression may be totally inadequate because
of the large surface areas involved, which in turn would require large
amounts of water. In some cases, wet dust suppression also reduces the
maximum production rate because of the added weight to the material being
processed.
The effectiveness of wet dust suppression depends on the characteristics
of the non-metallic mineral. For this reason and because it cannot be used
in all cases, wet dust suppression has not been selected as the basis for
the proposed standards. This should not be interpreted to mean, however,
that it cannot be used to achieve compliance with the proposed standards.
Wet dust suppression may be a very effective emission control system in some
cases and, if so, could be used to meet the standards.
In a dry collection system, particulate matter emissions generated
during process operations are controlled by capturing the emissions and
passing them through a collection device. The most efficient collection
device used in the non-metallic mineral industry is the fabric filter or
baghouse. Greater than 99 percent particulate collection control efficiency
can be attained on material even as small as submicron sizes. Data gathered
9-6
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during emission tests on baghouse units used to control a variety of
process operations at ten plants indicate that the size distribution of
particulate matter, the rock type processed, and the facility controlled
do not substantially affect baghouse performance.
Other collection devices used are cyclones and low energy scrubbers.
Although these collectors demonstrate 95 to 99 percent efficiency for
coarse particles (40 microns and larger), their efficiency for medium and
fine particles (20 microns and smaller) is less than 85 percent.
Because wet dust suppression cannot be used in all cases, it cannot
serve as the basis for standards of performance. There are two remaining
alternatives: to set no standards or to set standards based on dry emission
control systems. If no standards were set and only existing State regula-
tions were in effect, there would be an increase in nationwide particulate
matter emissions of about 45,000 megagrams per year (50,000 tons per year)
by 1985. Standards 'based on fabric filter control would reduce the increase
in emissions in 1985 to only 4,500 megagrams per year (5,000 tons per
year), a reduction of 90 percent over existing State regulations.
Standards would also reduce the potential increase in the ambient air
concentrations of particulate matter in the vicinity of new non-metallic
mineral processing plants. The maximum 24-hour average concentrations
with the proposed standards would range from about 10 to 50 yg/m while
the concentrations which would result if no standards were set could be
as high as about 100 to 450 yg/m assuming worst case meteorological
conditions.
There would be no adverse water pollution impact resulting from either
of the two alternatives. If no standards were set, plant processing
operations would continue as in the past with neither an increase nor a
9-7
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decrease in water consumption or discharge. The establishment of standards
based on dry emission control systems would not result in any water dis-
charge because the standards would not require the use of any water. If
wet dust suppression were used to meet standards based on dry control,
there would be an increase in water consumption but there would be no
significant water discharge because most of the water adheres to the
material being processed until it evaporates.
If no standards were set, there would be no solid waste impact other
than that resulting from normal operation. Standards based on dry control
would result in the collection of about 1.4 megagrams (1.6 tons) of solid
waste for every 250 megagrams (278 tons) of material processed. In many
cases, however, this material can be recycled back into the process, sold,
or used for a variety of purposes. Where no market exists, the material
is generally disposed of in the mine or in an isolated location in the
quarry. To prevent subsequent air pollution problems, the waste pile
should be protected from wind erosion. Methods for minimizing windblown
dust are discussed in the document entitled "Air Pollutant Control
Techniques for the Crushed and Broken Stone Industry" available from the EPA
Library (MD-35), Research Triangle Park, North Carolina 27711, telephone
number (919) 541-2777.
There would be no noise impact if no standards were set. The only
source of noise which would result from standards based on dry control
techniques would be the exhaust fans in the control system. When compared
to the noise from crushing and grinding process equipment, any additional
noise from control system exhaust fans would be insignificant.
Standards of performance based on dry control techniques would neces-
sarily result in an increase in energy usage. The estimated incremental
9-8
-------
energy requirements would result from the use of fabric filter baghouses to
control particulate matter emissions. The net increase in energy consumption
by all new plants for the year 1985 would be about 0.12 million megawatt
hours per year (0.34 million kilowatt-hours per day) or 15 percent over
that which would otherwise be required to meet the projected capacity
additions without any controls. The estimated incremental energy require-
ments of the proposed standards result from comparing the use of fabric
filter baghouses to control particulate matter emissions to the use of no
control system. The estimates indicate a greater impact than would
actually occur because it is expected that less-energy consuming wet dust
suppression systems would be used in some cases to achieve the proposed
standards. In addition, many new plants would use baghouses or combinations
of baghouses and water spray controls to meet existing State regulations.
The incremental increase in energy consumption at a particular plant
is dependent on the size of that plant. Although the amount of energy that
would be required would be more for a large plant than for a small plant,
the percentage increase in the plant's total energy consumption would be
less for a large plant than for a small plant. The total energy consumption
associated with air pollution control represents an increase in a plant's
total energy consumption of about 5 percent for a 136 Mg/hr (150 ton/hour)
plant to 14 percent for a 9.1 Mg/hr (10 ton/hour) plant having both
crushing and grinding operations. For plants with crushing operations
only, the increase would be about 19 percent for a 544 Mg/hr (600 ton/hour)
plant to 20.5 percent for a 9.1 Mg/hr (10 ton/ hour) plant.
The economic impacts associated with standards based on fabric
filter control techniques would not preclude building of most new plants.
However, discounted cash flow analysis indicates that the incremental costs
9-9
-------
associated with the best system of emission reduction may preclude the con-
struction of new common clay plants and pumice plants with capacities of
9.1 Mg/hr (10 ton/hr) or less, sand and gravel plants and crushed stone
plants with capacities of 22.7 Mg/hr (25 ton/hr) or less. For this
reason these plants would be exempt from the proposed standards.
While the standards are based on the use of dry emission control
techniques, less expensive wet dust suppression systems may be used in some
cases to achieve the proposed standards. Also many new plants would use
baghouses or a combination of baghouses and wet suppression to meet State
process weight regulations. Because the economic impact assessment compares
no control to dry control, the actual economic impact would be considerably
less than the summary presented below.
The capital costs for control equipment for a plant with crushing but
no grinding operations would range from $60,000 for a 9.1 Mg/hr (10 ton/hr)
plant to $336,000 for a 544 Mg/hr (600 ton/hour) plant or from 12 to 9
percent of the plant's total capital costs. For a plant with both
crushing and grinding operations, the capital costs would range from
$93,000 for a 9.1 Mg/hr (10 ton/hr) plant to $187,000 for a 136 Mg/hr
(150 ton/hr) plant or from 16 to 6 percent of the plant's total capital
costs. For a 181 Mg/hr (200 ton/hr) portable crushing plant, the capital
cost for control equipment would be $120,000 or 7 percent of the total
capital costs.
The total annualized costs for control at a crushing plant would range
from $14,000 to $87,000 per year, corresponding to $0.78 to $0.08/Mg ($0.72
to $0.07/ton) of product, as the plant capacity goes from 9.1 to 540 Mg/hr
(10 to 600 ton/hr). The annualized costs at a crushing and grinding plant
9-10
-------
would range from $21,000 to $44,000 per year or $0.28 to $0.04/Mg ($0.25
to $0.04/ton) of product as the plant capacity goes from 9.1 to 136 Mg/hr
(10 to 150 ton/hr). For a 181 Mg/hr (200 ton/hr) portable crushing plant,
the total annualized costs would be $28,500 per year or $0.08/Mg ($0.07/ton)
of product.
The total additional capital cost for all new plants would be about
$107 million for the first five years the proposed standards would be in
effect. These costs would vary for each industry, ranging from about
$93,000 for several minerals to $82.5 million for crushed stone. The
total annualized costs in the fifth year would increase by about $28
million, ranging from about $21,000 for vermiculite to more than $22
million for crushed stone. The average annualized control cost per ton
of output in 1985 would range from $0.005 for sand and gravel to $0.137
for kyanite. For all minerals, the annualized control cost is less than
two percent of the annual revenue for that industry.
The economic analysis conducted for non-metallic mineral processing
plants would apply also to integrated production plants, such as those at
lime plants, power plants and steel mills. The economic impact for integrated
production plants is expected to be the same or less for two reasons. First,
the integrated plants would have a lower cost of capital since they tend to
be affiliated with larger companies. Second, these plants would tend to pass
on control costs sooner because the control cost in terms of final product
value would be less. Therefore, all mineral processing equipment at lime
plants, power plants, steel mills, and other source categories which
operate separate mineral processing plants, would be covered by the
proposed standards. At asphalt concrete and Portland cement plants,
9-11
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process equipment would be subject to the standards if, in the process,
they precede equipment already covered by other standards of performance.
Comparison of the two alternatives, standards based on dry control
techniques versus no controls, indicates that the beneficial impacts of
setting standards outweigh the adverse impacts. A significant improvement
in air quality would result and there would be minimal adverse water pollu-
tion, solid waste and noise impacts. The increase in energy consumption
would not be significant and the costs and economic impacts would be reason-
able. Consequently, the proposed standards of performance for non-metallic
mineral processing plants are based on emission levels achievable using a
dry emission control system (fabric filters), which is the best system of
emission reduction.
9.4 SELECTION OF FORMAT FOR THE PROPOSED STANDARDS
In selecting the format for the proposed standards, it was necessary
to differentiate between the two types of particulate matter emissions at
non-metallic mineral processing plants: fugitive emissions and stack
emissions. Fugitive emissions are those which are not collected by a
capture system before they are released into the atmosphere. Stack emissions,
on the other hand, are those which are collected by a capture system and re-
leased into the atmosphere from a stack or duct. Fugitive emissions are
present when emissions generated at a point are not collected or captured.
They are also present when the capture system is not 100 percent effective
in collecting emissions. To ensure that all emissions at affected facilities
are controlled by the proposed standards, it is necessary to have one standard
for fugitive emissions, which effectively requires good collection or
capture of emissions, and another standard for stack emissions, which
effectively requires good control of emissions.
9-12
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9.4.1 Fugitive Emissions Standard
Two different formats could be selected to limit fugitive emissions
from non-metallic mineral processing plants: an equipment standard or a
visible emissions standard.
An equipment standard would require that emission points be enclosed or
equipped with hoods so that emissions would be captured and passed through
a control device. This format was not selected because it would be difficult
without measuring emissions to judge whether the control system was being
operated properly. Furthermore, the Clean Air Act permits the use of
equipment standards only when it is infeasible to set emission standards.
The second alternative format for controlling fugitive emissions is a
visible emissions standard. A visible emissions standard would specifically
limit the amount of time that visible fugitive emissions are allowed. A
visible emissions standard could be applied to any process operation regard-
less of whether or not it is enclosed. The standard would allow observations
to be made outside a building or buildings housing any part of an affected
facility. If no visible emissions were observed for more than the time allowed
by the standard, the facility would be in compliance. If there are pieces
of process equipment in the same building which are not covered by the
standard and visible emissions are observed outside the building, then the
visible emission observations would have to be made inside the building to
determine if they are being generated by a process operation included under
the proposed standards.
For the reasons discussed above, the selected format for controlling
fugitive emissions from non-metallic mineral processing plants is a visible
emissions standard.
9-13
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9.4.2 Stack Emissions Standard
Two different formats could be selected to limit stack emissions from
non-metallic mineral processing plants. A mass standard limiting emissions
in terms of mass emissions per unit of production or a concentration standard
limiting the concentration of particulate matter in the effluent gases could
be developed.
A mass standard may appear more meaningful in the sense that it relates
directly to the quantity of emissions discharged into the atmosphere. However,
a major disadvantage of a mass standard for non-metallic mineral processing
plants is that, typically, the production or feed rate of a process operation
is not measured over the short term. Thus, an accurate determination of the
weight of material processed through an affected facility would not be
possible.
A factor to consider when establishing a concentration standard is the
possibility of the standard being circumvented by diluting the air going to
the control device. This is unlikely to occur at non-metallic mineral pro-
cessing plants. Since the size and operating costs of the control device are
functions of the volume of gas treated, the cost of such a strategy probably
would be prohibitive. Consequently, a concentration standard was selected for
stack emissions at non-metallic mineral processing plants. To ensure that
the air pollution control system is properly installed, operated, and
maintained, an opacity standard is also being proposed.
9.5 SELECTION OF EMISSION LIMITS
9.5.1 Fugitive Emissions Standard
Observations of visible emissions were made at hoods and enclosures
to record the presence of fugitive emissions escaping capture. The length
9-14
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of observation time ranged up to 5 hours. No visible emissions were
observed from nine crushers for at least 90 percent of the time except for
one jaw crusher for which there were no visible emissions for only 77 percent
of the time. The data for the jaw crusher are not considered to be valid,
however, because a cover plate was removed during the observation period.
No visible emissions were observed from four grinding mills (two of which
were closed systems) for at least 94 percent of the time, for six screens,
three conveyor transfer points, one bucket elevator, one product bin and
two baggers. There were no visible emissions for 100 percent of the time
for 60 hours of observation of various parts of the process covered by the
standards.
Based on these visible emission observations, a standard is being
proposed to allow fugitive emissions from process operations other than
fine product loading to be visible for no longer than 10 percent of the time
over a minimum observation period of 1 hour.
Three visible emission tests were conducted at the railcar fine product
loading operation of a kaolin plant. For the two tests during which
rectangular hatch railcars were loaded, no visible emissions were observed
for 91 and 93 percent of the time. Visible emissions were observed for 12
percent of the time during loading of a "rake-back" railcar. In all three
tests the primary source of visible emissions was the topping of each com-
partment and the subsequent repositioning of the feed hose in the next
compartment. Visible emission tests were also conducted at truck and
railcar fine product loading stations at a feldspar plant. No visible
emissions were noted during truck loading. Visible emissions were observed
for about 15 percent of the time during the railcar loading test. Because
9-15
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tests at fine product loading stations at two plants found visible emissions
for more than 10 percent of the observation time, the standard proposed
for this operation would allow fugitive emissions to be visible for no
more than 15 percent of the time over a minimum observation time of 1 hour.
Since many segments of the non-metallic minerals industry locate
process equipment inside buildings, the visible emissions observations would
be made on emissions as they leave the building. If visible emissions
are observed for no more than 10 percent of the time (15 percent for fine
product loading), the affected facility would be in compliance with the
standard. If there are pieces of process equipment in the same building
which are not covered by the standard and visible emissions are observed
from the building for longer times than allowed by the standards, then
the observer must determine compliance by going inside the building to
observe emissions from the affected process equipment.
9.5.2 Stack Emissions Standard
The proposed concentration standard is based on the emission levels
achievable using fabric filtration (baghouses). Particulate matter emissions
were measured from baghouse collectors used to control emissions at crushing,
screening, and conveying (transfer points) operations at five crushed stone
installations; at grinding, classifying, and fine product loading operations
at a feldspar installation; and at four grinding operations at clay installa-
tions. The concentration of particulate matter emissions from these bag-
houses averaged 0.011 g/dscm (0.005 gr/dscf) and never exceeded 0.035 g/dscm
(0.016 gr/dscf). Additional test results in a study performed by the Industrial
Gas Cleaning Institute showed emission concentrations below 0.023 g/dscm (0.01
gr/dscf) for two fluid energy grinding mills processing clay (fuller's earth).
9-16
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Emissions from baghouses at one gypsum and two talc plants were also
measured. In all three tests, emissions exceeded the proposed standard of
0.05 g/dscm (0.02 gr/dscf). These test results were not representative of
either normal plant or proper baghouse operation. At the gypsum plant
frequent startup and shutdown did not allow the baghouse to build up the
necessary filter cake. Opacity readings ranged continuously from one to
six percent. Periodic visible puffing at one talc plant indicated either
that a torn bag was being used or that the baghouse was operated improperly,
Test results from the second talc plant indicated that emissions were well
above the baghouse manufacturers specifications. To verify that properly
designed and operated baghouses should have controlled emissions at these
plants to levels below the standard, additional tests were conducted at
plants processing fuller's earth and kaolin, two types of clay. These
clays were selected because their emissions contain particles as small or
smaller than those from gypsum and talc plants and therefore would be just
as difficult to control with a baghouse. The emission levels at these
clay plants were lower than the proposed standard, confirming that a
properly operated baghouse can control emissions to the level of the
standard even on very fine particles.
As discussed earlier, the emission data indicate that baghouse per-
formance is not substantially affected by the size distribution of
particulate matter, the rock type processed, or the operation controlled.
Therefore, although emission data are not available for all 20 non-
metallic mineral processing industries covered by the proposed standards,
the same emission levels can be achieved by all the industries. The
emission test results indicate that a level of 0.050 g/dscm (0.02 gr/dscf)
9-17
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can be achieved by all affected facilities when fabric filtration is used
properly. Therefore, the proposed concentration standard for stack
emissions from affected facilities is 0.05 g/dscm (0.02 gr/dscf).
A 1 percent opacity standard (based on 6-minute averages) is also pro-
posed. Opacity data were obtained during the emission tests on which the
concentration standard is based. Ninety-two percent of the 6-minute
averages showed zero percent opacity. The remaining 6-minute averages
were greater than zero but less than or equal to 1 percent opacity.
Therefore, a 1 percent opacity standard is being proposed to ensure the
proper operation and maintenance of the air pollution control device.
The opacity standard for stack emissions would be applicable in all
cases unless EPA were to approve establishment of a special opacity standard
under the provisions of 40 CFR § 60.11(e). The provisions allow an owner
or operator to apply to EPA for establishment of a special opacity standard
for any source which meets the applicable concentration standard but is
unable to meet the opacity standard because of an unusually large diameter
stack or other valid reason.
9.6 SELECTION OF PERFORMANCE TEST METHODS
A new reference method, Method 22, is being proposed to determine com-
pliance with the fugitive emissions standard. It determines the amount of
time that any visible emissions occur during the observation period, but
not the opacity of the emissions. The proposed method specifies that uncom-
bined water vapor is not considered visible emissions for determining
compliance with the standard.
Under the proposed standards, performance tests for particulate
matter emissions would be required for all air pollution control devices
9-18
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on process equipment. Particulate matter would be measured by Reference
Methods 1, 2, 3, and 5 or 17.
The proposed standards do not include any requirements for continuous
emission monitoring. At many non-metallic mineral plants, the cost of
operating continuous monitors on baghouses could be prohibitive. The
total annualized cost for a monitor could be as much as one-third the
annualized cost for a baghouse in some cases. Therefore, continuous
emission monitors would not be required by the proposed standards.
9-19
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APPENDIX A
EVOLUTION OF THE PROPOSED STANDARDS
A-l
-------
TABLE A-l. EVOLUTION OF THE PROPOSED STANDARDS
Date
Company, consultant or agency
Location
Nature of action
04/30/73 Arizona Portland Cement
Ideal Cement
Albuquerque Gravel Products
09/13/73 Harry T. Campbell and Sons
Texas Plants
10/13/73 Nello L. Teer Company
01/16/74
02/13/74
05/28/74
to
05/31/74
05/14/74
to
05/15/74
06/03/74
Paul L1me Plant, Inc.
Arizona Portland Cement Co.
Ideal Cement Co.
Albuquerque Gravel Products, Inc.
H.G. Fenton Material Co.
R1ll1to, AHz.
TIJeras, N. Mex.
Albuquerque, N. Mex.
Texas, Md.
Raleigh, N.C.
Douglas, Ariz.
R1ll1to, Ariz.
TIJeras, N. Mex.
Albuquerque, N. Mex,
San Diego, Calif.
Presurvey two sources.
Inspect haul road fugitive dust control
technique.
Measure visible emissions from the
asphalt batch plant.
Inspect stone processing and quarrying
operations.
Presurvey two quarries and stone pro-
cessing plants for partlculate testing.
Inspect crushed stone plants
Essex Bituminous Concrete Corp. Dracut, Mass.
Essex Bituminous Concrete Corp.
Blue Rock Industries
Lynn Sand and Stone Co.
Massachusetts Broken Stone Co.
Kentucky Stone Co.
Caldwell Stone Co.
Arizona Portland Cement Company
Peabody, Mass.
Westbrook, Maine
Swampscott, Mass.
Weston, Mass.
Russellvllle, Ky.
Danville, Ky.
R1ll1to, Ariz.
06/02/74 Arizona Portland Cement Company RIlHto, Ariz.
>Presurveys of five crushed stone plants
I for testing
\ Presurveys of two crushed stone plants
I for testing.
Conduct emission tests for partlculate
emission
Test report for partlculate emission
testing.
08/06/74 General Crushed Stone Co.
to Pennsy Supply Inc.
08/08/74 J. M. Brenner Stone Co.
09/16/74 Essex Bituminous Concrete Co.
10/28/74 Kentucky Stone Co.
11/19/74 J. M. Brenner Co.
12/27/74 Essex Bituminous Concrete Co.
Quakertown, Pa. Presurveys for partlculate emission test!
Harrlsburg, Pa.
Lancaster, Pa.
Dracut, Mass. Trip report of emission tests on stone
crushing operations.
Russellvllle, Ky. Tests conducted for process and fugitive
emissions.
Lancaster, Pa. Source test of two baghouse operations
at crushed stone plant.
Dracut, Mass. Source testing report of stone crushing
operation.
(continued)
A-2
-------
TABLE A-l (continued)
Date Company, consultant or agency
Location
Nature of action
12/20/74 Fc^rrantp and Sons
06/30/75 Kentucky Stone Co.
07/OR/75 Arizona Portland Cement
11/13/75 Massachusetts Broken Stone Co.
04/13/76 Blue Ridge Stone Corp.
OS/06/76 Potash Company of America
05/27/76 Dravco Corp.
05/12/76 GREFCo, Inc.
Ob/11/76 U.S. Borax
05/27/76 Dravco Corp.
06/10/76 Flintkote Co.
06/24/76 Englehard Minerals and
Chemicals Co.
06/23/76 Georgia Kaolin Co.
07/08/76 Standard Slag Co.
07/09/76 Ozark-Mahoning Co.
07/07/76 International Salt Co.
07/06/76 Eastern Magnesia Talc Co.
08/26/76 Massachusetts Broken Stone
09/27/76 International Minerals and
Chemicals Corp.
Bernardsville, N.J.
Russellville, Ky.
Rill 1 to, Ariz.
Weston, Mass.
Martinsvllle, Va.
Carlsbad, N. Mex.
Newtown, Ohio
Socorro, N. Mex.
Boron, Calif.
Newtown, Ohio
Las Vegas, Nev.
Attapulgus, Ga.
Dry Branch, Ga.
Warren, Ohio
Rosiclare, 111.
Retsof, N.Y.
Johnson, Vt.
Weston, Mass.
Spruce Pine, N.C.
Emission test report of stone
crushing operation.
Source tests on primary, secondary
crushers, three deck screens, and
crusher feed hopper.
Trip report of visible emissions obser-
vations at stone crushing facility.
Report on observation of visible emis-
sion at stone processing operation.
Plant visit to study process operation
at crushed stone plant.
Plant visit to study processing of
potash ore.
Plant visit to study processing of
sand and gravel and the resultant
particulate emissions.
Plant visit to study processing of
perlite ore and the resultant par-
ticulate emissions.
Plant visit to study processing of
borate ore and resultant particulate
emissions.
Plant visit, made by PEDCo Environmental
Specialists, Inc.
Plant visit made by PEDCo and EPA to
study gypsum processing operations.
Plant visit to observe fuller's earth
processing and resultant particulate
emissions.
Plant visit to observe kaolin proces-
sing operations and resultant particu-
late emissions.
Plant visit to observe slag processing
and resultant particulate emissions.
Plant visit to observe fluorspar pro-
cessing and resultant particulate
emissions.
Plant visit to observe rock salt pro-
cessing and resultant particulate
emissions.
Plant visit to observe talc pro-
cessing and resultant particulate
emissions.
Visible emissions tests conducted at
stone processing operations.
Source sampling at feldspar milling
operation for particulates.
(continued)
A-3
-------
TABLE A-l (continued)
Date
10/25/76
Company, consultant or agency
Location
Flintkote Co.
10/?l/76 Lastorn Magnesia Talc Co.
11/10/70
05/09/77 Pfeizer Inc.
05/10/77 Johns-Manville Corp.
06/20/77 Pfc'izer, Inc.
06/20/77 Pfeizer, Inc.
07/11/78 National Air Pollution
Control Techniques and
Advisory Committee
(NAPCTAC)
National Asphalt Pavement
Association
OH/16/78
08/29/78 Kaolin Industry
09/14/78 National Slag Association
10/03/78 National Limestone Institute
12/05/78 Georgia Kaolin Company
12/06/78 Thiele Kaolin Company
12/20/78 Fdward C. Levy Co.
Colorado Sand and Gravel
Association
01/09/79
01/10/79 North State Pyrophyllite Company
01/22/79 Gypsum Association
02/21/79
to
02/23/79
Colorado Sand and Gravel
Association
01/06/79 Refractories Institute
01/19/79 [owa Manufacturing CD.
Blue Diamond, Nev.
Johnson, Vt.
Victorville, Calif.
Lompoc, Calif.
Victorville, Calif.
Victorville, Calif.
Raleigh, N.C.
Durham, N.C.
Durham, N.C.
Durham, N.C.
Washington, D.C.
Dry Branch, Ga.
Sandersville, Ga.
Detroit, Mi.
Durham, N.C.
Greensboro, N.C.
Durham, N.C.
Denver, Col.
Durham, N.C.
Durham, N.C.
Nature of action
Stationary source testing of gypsum
milling operation.
Stationary source testing at several
milling operations at talc processing
plant.
Source sample analysis for physical
characteristics of particulate samples
from several plants.
Presurvey talc grinding operations for
possible source testing.
Presurvey diatomite processing oper-
ations for possible source testing.
Source test on pebble mill at talc pro-
cessing plant.
Source emission test report performed
by Pacific Environmental Services, Inc.
Meeting with non-metallic industry
spokesmen to discuss proposed NSPS.
Meeting with National Asphalt Pavement
Association to discuss proposed NSPS.
Meeting between EPA and the Kaoline
Industry to discuss the proposed NSPS
as it pertains to the Kaolin Industry.
Meeting between EPA and the associa-
tion to discuss the proposed NSPS as
it pertains to the slag industry.
Meeting between Institute and EPA to
discuss proposed NSPS as it pertains to
the limestone industry.
Source test report on Raymond Impact
Mill and Roller Mill.
Fugitive emission testing at product
loading facility at kaolin plant.
Plant visit by GCA/Technology Division
to observe slag processing and
resultant particulate emission.
Source testing performed by Clayton
Associates same date.
Meeting with EPA to discuss proposed
NSPS.
Meeting with GCA/Technology Division
to discuss problems plant would have
with proposed NSPS.
Meeting between the Association and
EPA to discuss the proposed NSPS as
it pertains to the gypsum industry.
GCA/Technology Division visited sev-
eral sand and gravel processing plants
and met with the Association to
discuss the proposed NSPS as well as
to observe process and emission
control techniques used at the sand and
gravel plants.
Meeting between Institute and EPA to
discuss the proposed NSPS as il per-
tains to thr' Kefrvn.(.ories indir l,ry.
Meeting between comp.my Jrid LI'A lo
discuss the proposed NSPS as il per-
tains to the crushed stone industry.
A-4
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APPENDIX B
INDEX TO ENVIRONMENTAL IMPACT CONSIDERATIONS
This appendix consists of a reference system, cross-indexed with the
October 21, 1974 FEDERAL REGISTER (39 FR 37419) containing the Agency guide-
lines concerning the preparation of Environmental Impact Statements. This
index can be used to identify sections of the document which contain data
and information germane to any portion of the FEDERAL REGISTER guidelines.
B-l
-------
CROSS INDEXED REFERENCE SYSTEM TO HIGHLIGHT
ENVIRONMENTAL IMPACT PORTIONS OF THE DOCUMENT
Agency Guideline for Preparing Regulatory Action
Environmental Impact Statements (39 FR 37419)
Location within the
Background Information Document (BID)
1. Background and description of the proposed action.
Describe the recommended or proposed action and
its purpose
2. Alternatives to the proposed action.
Describe and objectively weigh reasonable
alternatives to the proposed action, to the
extent such alternatives are permitted by
the law. . For use as a reference point to
which other actions can be compared, the anal-
ysis of alternatives should include the al-
ternative of taking no action, or of post-
poning action. In addition, the analysis
should Include alternatives having different
environmental impacts, including proposing
standards, criteria, procedures, or actions
of varying degrees of stringency. When
appropriate, actions with similar environ-
mental impacts but based on different tech-
nical approaches should be discussed. This
analysis shall evaluate alternatives in such
a manner that reviewers can judge their re-
lative desirability.
Thr analysis should be sufficiently detailed
to reveal the Agency's comparative evaluation
of the beneficial and adverse environmental,
health, social, and economic effects of the
proposed action and each reasonable
alternative.
Where the authorizing legislation limits the
Agency from taking certain factors into account
in its decisionmaking, the comparative evalua-
tion should discuss all relevant factors, but
clearly identify those factors which the
authorizing legislation requires to be the
basis of the decisionmaking.
The proposed standards are summarized in chapter 1,
section 1.1. The statutory basis for the proposed
standards (section 111 of the Clean Air Act, as amended)
is discussed in the Introduction. The purpose of the
proposed standards is discussed in chapter 9, section
9.1.
The alternative control systems, based upon the best
combinations of control techniques, are presented in
chapter 6. A discussion of the alternative of taking
no action and that of postponing the proposed action
is presented in chapter 9, section 9.3. The alterna-
tive systems are discussed throughout the document in
the evaluation of the environmental and economic im-
pacts associated with the proposed standards.
The selection of the best system for emission reduction,
considering costs, is presented in chapter 9, section 9.3.
The alternative formats for the proposed standards are
discussed and the rationale for the selection of the
proposed formats are discussed in chapter 9, section 9.4.
The emission limits for particulate matter and the ra-
tionale for their selection are discussed in chapter 9,
section 9.5. The alternatives considered in the selec-
tion of a visible emissions standard is presented in
chapter 9, section 9.6.
A summary of the environmental and economic impacts
associated with the proposed standards are presented
in chapter 1, section 1.2.
A detailed discussion of the environmental effects of
each of the alternative control systems can be found
in chapter 7. This chapter includes a discussion on
the beneficial and adverse impacts on air, water,
solid waste, energy, noise, and other environmental
considerations.
A detailed analysis of the costs and economic impacts
associated with the proposed standards can be found in
chapter 8.
The factors which the authorizing legislation requires
to be the basis of the decisionmaking are discussed
in the Introduction.
(continued)
B-2
-------
CROSS INDEXED REFERENCE SYSTEM TO HIGHLIGHT
ENVIRONMENTAL IMPACT PORTIONS OF THE DOCUMENT (continued)
Agency Guideline for Preparing Regulatory Action
Environmental Impact Statements (39 FR 37419}
Location within the
Background Information Document (BID)
In addition, the reasons why the proposed
action is believed by the Agency to be the
best course of action shall be explained.
3. environmental impact of the proposed action.
A. Primary impact
Primary impacts are those that can oe
attributed directly to the action, such as
reduced levels of specific pollutants
brought about by a new standard and the
physical changes that occur in the various
media with this reduction.
II. Secondary impact
Secondary impacts are indirect or induced
impacts. For example, mandatory reduction
of specific pollutants brought about by
A new standard could result in the adoption
of control technology that exacerbates
another pollution problem and would be a
secondary impact.
1. Other considerations
A. Adverse impacts which cannot be avoided
should the proposal be implemented. Describe
the kinds and magnitudes of adverse impacts
which cannot be reduced in severity to an
acceptable level or which can be reduced to
an acceptable level but not eliminated.
Ihese may include air or water pollution,
damage to ecological systems, reduction in
economic activities, threats to health, or
undesirable land use patterns. Remedial,
protective, and mitigative measures which will
be taken as part of the proposed action shall
be identified.
B. Relationship between local short-term uses of
man's environment and the maintenance and
enhancement of long-term productivity.
Describe the extent to which the proposed
action involves trade-offs between short-
term environmental gains at the expense of
long-term losses or vice versa and the ex-
tent to which the proposed action forecloses
future options. Special attention shall be
qiven to effects which pose long-term risks
to health or safety. In addition, the timing
of the proposed action shall be explained and
justi fied.
('.. Irreversible and irretrievable commitments of
resources which would be involved in the pro-
posed action should it be implemented. De-
scribe the extent to which the proposed action
curtails the diversity and range of beneficial
uses of the environment. For example, irre-
versible damage can result if a standard is
not sufficiently stringent.
The rationale for the selection of particulate matter
from non-metallic mineral plants for control under the
proposed standards is discussed in chapter 9, section
9.1.
The Administrator's decision to control particulate
emissions under Federal standards and the reasons for
regulating particulate under section 111 of the Clean
Air Act is discussed in the Introduction.
The primary impacts on mass emissions and ambient air
quality due to the alternative control systems is
discussed in chapter 7, section 7.1.1. These impacts
are summarized in Table 1.1, Matrix of Environmental
and Economic Impacts of the Alternative Standards,
chapter 1, section 1.2.
The secondary environmental impacts attributable to
the alternative control systems are discussed in
chapter 7. Secondary impacts on air quality are dis-
cussed in chapter 7, section 7.4.
The anticipated impacts on energy requirements due to
each alternative control system is discussed in
chapter 7, section 7.4.
A summary of the potential adverse environmental and
economic impacts associated with the proposed stan-
dards and the alternatives that were considered is
discussed in chapter 1 and chapter 7.
A discussion of the effects of particulate emissions
from the non-metallic mineral industry is included in
chapter 9, section 9.1.
Irreversible and irretrievable commitments of resources
are discussed in chapter 1, section 1.2.
B-3
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APPENDIX C
SUMMARY OF TEST DATA
A test program was undertaken by EPA to evaluate the best particulate
control techniques available for controlling particulate emissions from
non-metallic mineral plant process operations including crushers, screens
and material handling operations, especially conveyor transfer points. In
addition, a control technique for grinding operations was also evaluated.
This appendix describes the process operations tested (their operating con-
ditions, characteristics of exhaust gas streams and, where applicable, de-
viations from prescribed test procedures) and summarizes the results of the
particulate emission tests and visible emission observations.
Sixteen baghouse collectors controlling process operations at five
crushed stone installations (three limestone and two traprock), one kaolin,
and one fuller's earth plant were tested using EPA Reference Method 5 except
as noted in the facility descriptions for determination of particulate matter
from stationary sources. Baghouse collectors utilized to control particulate
emissions from grinding operations at a feldspar, gypsum, and two talc plants
were also tested, but EPA Reference Method 17 was used for determination of
particulate matter. Results of the front-half catches (probe and filter)
from the particulate emission measurements conducted are shown in Figure C-l
and the complete results are summarized in the Tables herein.
Visible emission observations were made at the exhaust of each of the
above control devices in accordance with procedures recommended in EPA
C-l
-------
Reference Method 9 for visual determination of the opacity of emissions from
stationary sources.
At the hoods and collection points for the process facilities, the
visible emission opacity observations were made in accordance with procedures
recommended in EPA Reference Methods 9 and 22 and the data are presented in terms
of percent of time equal to or greater than a given opacity or in percent of
total time of visible emissions as in Table 80. Visible emission observations
were also made at a traprock installation and a feldspar crushing plant where
particulate emissions are controlled by dust suppression techniques.
DESCRIPTION OF FACILITIES
Al. Primary crushing stage incorporating a pan feeder, vibrating grizzly,
impact breaker, T-bar belt feeder and a primary belt conveyor. The impactor
is rated at 1,000 TPH and used to reduce run-of-quarry limestone (cement rock)
to 2 1/2-inch minus. Particulate emissions generated at various points are
confined, captured and vented to a jet pulse type baghouse for collection.
Tests were conducted only during periods when the process was operating
normally. Particulate measurements were performed using EPA Method 5. Visible
emission observations were made at the baghouse exhaust and at capture points
in accordance with EPA Method 9.
A2. Primary scalping screen used for scalping the primary crusher
product of facility Al. The plus 2 1/2-inch oversize is chuted to a belt
conveyor and returned to the primary for recrushing. The screen throughs
are also discharged to a conveyor and transported to a storage facility.
Particulate emissions generated from the top of the screen, which is
totally enclosed, and from both chute-to-belt transfer points are aspirated
to a jet pulse baghouse for collection. Tests, using EPA Method 5, were
C-2
-------
conducted simultaneously with those at facility Al. Sampling during all
three tests runs reported herein was overisokinetic. Visible emission
observations were made at the baghouse exhaust using EPA Method 9.
A3. Conveyor transfer point at the tail of an overland conveyor, also
located at installation Al. The 30-inch belt conveyor has a 900 TPH
capacity at a belt speed of 700 FPM. The transfer point is enclosed and
emissions vented to a small baghouse unit for collection. Three particulate
samples were collected using EPA Method 5. Visible emission observations
were made at the baghouse outlet and at the transfer point using EPA
Method 9.
A4. The secondary crushing and screening stage at installation Al.
consisting of a vibrating screen and a cone crusher. Minus 2 1/2-inch
material is fed to the screen at about 165 TPH where it is separated in two
fractions, plus 3/4-inch and 3/4-inch minus. The oversize fraction is
discharged to the cone crusher and reduced to 3/4-inch. The crusher product
and screen throughs are then conveyed to a milling circuit. Dust control
is effected by capturing and venting emissions from the screen and crusher
to a jet pulse baghouse for collection. Both particulate measurements and
visible emission observations were made at the collector outlet using EPA
Methods 5 and 9, respectively.
Bl. Primary impact crusher used for the initial reduction of run-of-
quarry limestone rock to three inches. The normal production rate through
this primary crushing stage is 350 TPH. Particulate emissions are collected
from the impact crusher at its discharge hopper and from the discharge hopper
to primary conveyor belt transfer point and then controlled by a fabric filter
C-3
-------
collector. The fabric filter is mechanically shaken twice daily for
cleaning. EPA Method 5 was used for participate measurements and EPA
Method 9 was used for visible emission readings at the collector exhaust and at
the impact crusher.
B2. Secondary and tertiary crushing and screening facilities at the
same installation as Bl. These consist of a scalping screen, a 4-foot
cone crusher, two 3-foot cone crushers, a hanunermill used to produce
agstone and two final sizing screens. The plant has a 300 TPH design
capacity, crushing to 1 1/2-inch minus, including, 60 TPH of agstone. Dust
control throughout this plant is affected by enclosing or hooding dust
producing points and venting captured emissions to a fabric filter for
collection. The collector is mechanically shaken twice daily for cleaning.
Pickup points include the top of the scalping screen, both the feed and
discharge of all three cone crushers, the discharge of the hamrnermill, the
top of both finishing screens, five product bins and six conveyor transfer
points. Three particulate measurements were made in accordance with EPA
Method 5. In addition, visible emission observations were made at the
baghouse exhaust and at the process facilities controlled using EPA
Method 9.
B3. The same facility as B2, except that particulate emission
measurements were made using an in-stack filter. Testing was conducted
simultaneously with that described in B2.
Cl. Limestone crushing plant consisting of a primary jaw crusher,
scalping screen and hamrnermill. The rated capacity of the plant is 125
TPH. End products produced range from 1 1/2-inch minus dense-graded road
base stone to minus 1/8-inch screenings. Particulate emissions are
controlled by a mechanical shaker type baghouse. Collection points include
the primary crusher discharge, the scalping screen throughs to stacking
C-4
-------
conveyor transfer point, and both the hammerm1ll feed and discharge.
Tests were conducted using EPA Methods 5 and 9.
C2. Two 3-deck vibrating screens used for final sizing at the same
Installation as Cl. Both screens are totally enclosed and partlculate
emissions collected from the top of both screens, at the feed to both
screens, and at both the head and tall of a shuttle conveyor between the
screens are vented to a mechanical shaker type baghouse. Again, tests were
conducted in accordance with EPA Methods 5 and 9.
Dl. Secondary and tertiary crushing and screening facilities used
for processing traprock at 250 TPH. The process facilities include a
scalping screen, a 4-foot secondary cone crusher, two sizing screens and two
4-foot tertiary cone crushers. All process facilities are enclosed and
partlculate emissions are vented to one of two baghouses for collection.
The baghouses are exhausted through a common stack. Particulate measurements
were conducted using EPA Method 5. Visible emission observations using
EPA Method 9 were also made at the collector exhaust and at the process
facilities controlled.
D2. Finishing screen at the same installation as facility Dl. The
screen is totally enclosed and emissions collected from the top of the
screen enclosure, all screen discharge points, and several conveyor transfer
points are vented to a fabric filter. Tests conducted were identical
to those at Dl and were performed simultaneously.
El. Tertiary crushing and screening facilities at a 375 TPH traprock
installation. Process facilities include two sizing screens, four 4 1/4-foot
C-5
-------
cone crushers and several conveyor transfer points. Both screens are
enclosed and emissions are collected by the enclosures and at the throughs
discharge. The tertiary cone crushers are hooded and vented at both feed
and discharge points. Captured emissions are collected by a jet pulse type
baghouse. Tests using EPA Method 5 were conducted during periods of normal
operation. Although desirable, the pressure drop across the baghouse could
not be monitored because the pressure gauge was Inoperative. Visible emission
observations were also made of the baghouse exhaust using EPA Method 9.
E2. Five screens used for final sizing and eight storage bins at the
same installation as El. All screens and bins are totally enclosed and
emissions vented to a jet pulse type baghouse for collection. Tests
conducted were Identical to and performed simultaneously with those at
facility ET.
Fl. Tertiary crushing and screening facilities used to reduce run-of-
quarry trap rock. Particulate emissions are controlled by spraying
water at critical dust producing points in the process flow. Two to three
percent moisture 1s added to the material to suppress dust. Visible emission
observations were made 1n accordance with EPA Method 9 procedures.
Gl. Grinding system incorporating a belt feeder, ball mill, bucket
elevator, separator and a belt conveyor. The ball mill is used to reduce
feldspar to minus 200 mesh. Particulate emissions generated at various
points are confined, captured and vented to a reverse air type baghouse
for collection. Particulate measurements were performed using EPA Method 17.
Visible emission observations were made at the baghouse exhaust and all
capture points in accordance with EPA Method 9.
C-6
-------
G2. Crushing facilities (primary and secondary) used to reduce feldspar
to minus 1.5 inches. Dust control 1s affected by the suppression techniques.
Surface moisture contents were 1.6 to 1.8 percent at the primary crusher
discharge, 1.4 to 1.5 percent at the secondary crusher feed, and 1.0 percent
at the secondary crusher discharge conveyor. Visible emission observations
were made at all process facilities in accordance with EPA Method 9
procedures.
HI. Raymond roller mill used to grind gypsum. The ground product from
the mill is air-conveyed to a cyclone collector for product recovery. The
air 1s returned to the mill. Excess air is vented to a baghouse. Visible
emission observations were made to determine leaks from the system in
accordance with EPA Method 9 procedures.
H2. Same facility as HI. Particulate measurements and visible emission
observations were made at the baghouse exhaust in accordance with EPA
Methods 5 and 9.
I. Bagging operation used to package ground mica. Particulate
emissions are controlled by a baghouse. Visible emission observations
were made at the capture point in accordance with EPA Method 9 procedures.
Jl. Crushing (primary and secondary), grinding (pebble mill and vertical
mill) and bagging operations at a talc processing plant. Particulate emis-
sons are controlled by a baghouse. Visible emission observations were
made at the capture points in accordance with EPA Method 9 procedures.
J2. Same facility as Jl. Particulate measurements and visible emission
observations were made at the baghouse exhaust in accordance with EPA
Methods 5 and 9.
C-7
-------
K. Pebble mill used to grind talc. Captured emissions are vented to a
pulse type baghouse for collection. Particulate measurements and visible
emission observations were made at the baghouse exhaust in accordance with
EPA Methods 5 and 9.
LI. Raymond Impact Mill used to grind kaolin. Captured emissions are
exhausted to a baghouse for collection. EPA Methods 5 and 9 were used for
particulate measurement and visible emission observation at the baghouse stack,
respectively.
12. Roller Mill used at same plant as LI. Further grinding of kaolin
is accomplished. Collection of captured emissions takes place in a baghouse
which was tested for the same parameters as LI, again by EPA Methods 5 and 9.
Ml. Roller mill used to grind fuller's earth clay. Captured
emissions are exhausted to a baghouse for collection. Particulate measure-
ments and visible emission observations were made at the baghouse exhaust
in accordance with EPA Methods 17 and 9.
M2. Fluid energy mill used to grind fuller's earth clay at same
plant as Ml. Captured emissions are exhausted to a baghouse for collection.
EPA Methods 17 and 9 were used for particulate measurement and visible
emission observation at the baghouse stack, respectively.
N. Kaolin rail car loading operation. Three complete rail car
loadings were evaluated for fugitive emissions in accordance with EPA
Method 22 test procedures. A baghouse (collection system) is used to
collect dust that is captured in the loading area.
C-8
-------
0.02
0.015
_ 0.034
I/) -Q
:z: 3
o o
>— ro
2: TJ
10
I i I -4-)
0.01
0.005
Faci11ty
Rock Type
r ~~\ to —
KEY n
H-H AVERAGE
4' EPA TEST METHOD
O OTHER TEST METHOD
ft *
fl N
II H
HI! fc
W 1 1
-
1 1 h
' i
1 1
1 1
-6
J t L T
1 1
R A l(j f\
w i1
t? II 1
ij [t * 1
( I r '
ii> 4-ji
p i
ft ! i ft
to ll-
IU ft « jj
d y y ^ i*
1 1 1 1 9 1 1 1 1 1 1 1 1 1
Al A2 A3 A4 Bl 82 B3 Cl C2 Dl D2 El E2 Gl LI L2 Ml M2
L LL LL LL LL TT TT FKK FE.FE
0.046
Ol
o
-Q
_ 0.023
t
x>
0)
Q_
E
It)
. 0.011
Figure 1. Particulate emissions from non-metallic minerals
processing operations.
C-9
-------
Table 1
FACILITY Al
Summary of Resu'l ts
(1)
Run liumber
Date
'Test Time-minutes
Production rate - TPH
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature - °F
Water vapor - Vol.%
Visible Emissions at
Collector Discharge -
Percent Opacity
Particulate Emissions
Prohg and Filter Catch
•gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total Catch
(2)
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
(1) Based on throughput through primary crusher.
(2) Back-half sample for run number 1 was lost.
6/10/74
400
995
26430
22351
81.0
2.5
0.00471
0.00398
0.90
0.00091
-
-
-
-
6/11/74
320
1027
26653
22140
88.0
3.0
See Tables
0.00504
0.00419
0.96
0.00102
0.00597
0.00495
1.13
0.00121
6/12/74
240
1010
27142
22502
88.0
3.3
2 and 3
0.00727
0.00602
1.40
.0.00139
0.00839
0.00695
1.62
0.00160
Hi
320
ion
26472
22331
85.7
2.9
0.0056
0.004)
1.07.!
0.00 11
0.0071
0.0051
1.38
0.001*
C-10
-------
TABLE 2
FACILITY AT
.(1)
Summary of Visible Emissions
: 6/4/74 - 6/5/74
of Plant: Crushed Stone - Primary Crusher
of Discharge: Stack Distance from Observer to Discharge Point: 75 ft
ition of Discharge: Baghouse Height of Observation Point: Ground-level
Iht of Point of Discharge: 14 ft. Direction of Observer from Discharge Point: N.E.
;ription of Background: Grey building
iription of Sky: Clear
i Direction: East
)r of Plume: None
Wind Velocity: 0-5 mi/hr.
Detached Plume: No
ition of Observation: 6/4/74 - 78 minutes
6/5/74 - 210 minutes
SUMMARY OF AVERAGE OPACITY
(1)
Time
Set Number
1 through 6
7 through 9
10 through 13
14 through 48
Start
8:50
11:23
12:12
8:11
End
9:26
11:41
12:36
11:41
Opacity
Sum
0
0
0
0
Average
0
0
0
0
Readings were 0 percent opacity during all periods of observation.
observers made simultaneous readings.
C-ll
-------
FACILITY Al
SUMMARY OF VISIBLE EMISSIONS*
Date: 7/8/7b 7/9/75
Tyoe of Plant: Crushed stone (cement rock)
Type of Discharge: Fugitive
Location of Discharge: Primary impact crusher discharge
Height of Point of Discharge: 6 feet
Description of Background: Grey wa11
•Description of Sky: N.A. (indoors)
Wind Direction: N.A.
Color of Plume: White
Duration of Observation:
Distance from Observer to Discharge Point: 15 feet
Height of Observation Point: Ground level
Direction of Observer from Discharge Point: SE
Wind Velocity: No wind (indoors)
Detached Plume: No
7/8/75 - 2 hours
7/9/75 - 2 hours
Summary of Data:
Ooacity,
Percent
5
n
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
3
0
0
0
0
-
-
-
-
or
Opacity
Sec.
30
30
15
15
0
-
-
-
-
-
Opacity,
Percent
55
60
65
70
75
80
85
90
15
100
Total Time Equal to or
Greater Than Given Opacity
Min. Sec.
Sketch Showing How Opacity Varied With Time:
Not Available
Ł20
O
Sis
>•
t: 10
o
o 5
0
-H-
7/8/75
Z '' 0
TIME, hours
7/9/75
(1) Two observers made simultaneous readings^ the greater of their readings
is reported.
C-12
-------
TABLE 4
FACILITY A2
Summary of Results
Run Number
1
Average
Date
6/10/74
6/11/74 6/12/74
Test Time - Minutes
Production Rate - TPH^
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature - °F
Water vapor - Vol . %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions ^ '
Probe and filter catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total catch ^ '
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
400 320
965 1023
15797 15771
13368 13246
90.0 90.0
1.4 2.1
SEE TABLE 5
0.00176 0.00188
0.00149 0.00158
0.20 0.21
0.00021 0.00024
0.00235
0.00197
0.27
0.00030
240
1056
15866
13196
94.0
2.5
0.00222
0.00184
0.25
0.00024
0.00314
0.00261
0.36
0.. 00034
320
1015
15811
13270
91.3
2.0
0.00195
0.00164
0.22
0.00023
0.00275
0.00224
0.32
0.00032
(1) Throughput through primary crusher.
(2) All three test runs were over-isokinetic.
(3) Back-half sample for run number 1 was lost.
C-13
-------
TABLE 5
FACILITY A2
Summary of Visible Emissions^ '
Date: 6/10/74 - 6/11/74
Type of Plant: Crushed Stone - Primary Screen
Type of Discharge: Stack Distance from Observer to Discharge Point: 60 f
Location of Discharge: Baghouse Height of Observation Point: Ground-level
Height of Point of Discharge: 10 ft. Direction of Observer from Discharge Point: Easi
Description of Background: Sky
Description of Sky: Clear
Wind Direction: Southwest Wind Velocity: 0-2 mi/hr.
Color of Plume: None Detached Plume: No
Duration of Observation: 6/10/74 - 192 minutes
6/11/74 - 36 minutes
SUMMARY OF AVERAGE OPACITY
(1)
Set Number
1 through 11
12 through 32
33 through 38
Time
Start
10:35
12:30
9:40
End
11:41
2:36
10:16
Sum
0
0
0
Opacity
Average
0
0
0
Readings were 0 percent opacity during all periods of observation.
'Two observers made simultaneous readings.
C-14
-------
Run Number
Date
TABLE 6
FACILITY A3
Summary of Results
1
6/10/74 6/11/74 6/12/74
Average
Test Time - Minutes
Process Weight Rate - TPH
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature - °F
Water vapor - Vol . %
Visible Emissions at
Collector Discharge -
Fugitive (% Opacity)
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total catch ^ '
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
360 288
910 915
2303 2313
1900 1902
98.0 101.0
2.4 2.4
SEE TABLES
0.00095 0.00162
0.00078 0.00134
0.02 0.03
0.00002 0.00003
0.00190
0.00156
0.03
0.00003
288
873
2422
2003
97.0
2.3
7
0.00207
0.00171
0.04
0.00004
0.00259
0.00214
0.04
0.00005
312
899
2346
1935
98.7
2.4
0.00155
0.00128
0.03
0.00003
0.00224
0.00185
0.035
0.00004
(1) Back-half sarnie for run number 1 was lost.
C-15
-------
TABLE 7 ,
FACILITY A3
Summary of Visible Emissions1"
Date: 6/11/74
Type of Plant: Crushed Stone - Conveyor Transfer Point
Type of Discharge: Stack Distance from Observer to Discharge Point: 60
Location of Discharge: Baghouse Height of Observation Point: Ground-level
Height of Point of Discharge: 8 ft. Direction of Observer from Discharge Point: N
Description of Background: Grey apparatus
Description of Sky: Clear
Wind Direction: Westerly Wind Velocity: 0-10 mi/hr.
Color of Plume: None Detached Plume: No
Duration of Observation: 240 minutes
SUMMARY OF AVERAGE OPACITY
Time Opacity
Set Number Start End Sum Average
1 through 30 10:40 1:40 0 0
31 through 40 1:45 2:45 0 0
Readings were 0 percent opacity during all periods of observation.
^ 'Two observers made simultaneous readings.
C-16
-------
Run Number
Date
TABLE.8
FACILITY A4
Summary of Results
1
6/6/74 6/7/74
Average
6/8/74
Test Time - Minutes
Production Rate - TPH
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature - °F
Water vapor - Vol . %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
320
170
10579
9277
81.0
2.3
0.00036
0.00031
0.03
0.00017
0.00047
0.00041
0.04
0.00022
320 320
162 152
9971 11045
8711 9656
77.0 80.0
2.2 2.1
SEE TABLES 9 & 10"
0.00075 0.00074
0.00065 0.00065
0.06 0.06
0.00034 0.00041
0.00104
0.00095
0.08
0.00050
320
163
10532
9214
79.3
2.2
0.00062
0.00054
0.05
0.00031
0.00678
0.00068
0.06
0.00034
C-17
-------
TABLE .9
FACILITY A4
Summary of Visible Emissions^ '
Date: 6/6/74
Type of Plant: Crushed Stone - Secondary Crushing and Screening
Type of Discharge: Stack Distance from Observer to Discharge Point: IOC
Location of Discharge: Baghouse Height of Observation Point: Ground-level
Height of Point of Discharge: 15 ft. Direction of Observer from Discharge Point: Nc
Description of Background: Sky
Description of Sky: Clear
Wind Direction: Variable Wind Velocity: 0 to 10 mi/hr.
Color of Plume: None Detached Plume: No
Duration of Observation: 240 minutes
SUMMARY OF AVERAGE OPACITY
(1)
Time Opacity
Set Number Start End Sum Average
1 through 30 10:40 1:40 0 0
31 through 40 1:45 2:45 0 0
Readings were 0 percent opacity during all periods of observation.
^ 'Two observers made simultaneous readings.
C-18
-------
FACILITY A 4
SUMMARY OF VISIBLE EMISSIONS
(1!
Date: 7/9/75 7/10/75
Type of Plant: Crushed stone (cement rock)
Tyne of Discharge: Fugitive
Location of Discharge: Conveyor (transfer point)
Height of Point of Discharge: 8 feet
Description of Background: Sky
Ascription of Sky: Partly cloudy
Wind Direction: South
Color of Plume: White
Distance from Observer to Discharge Point: 50 feet
Heiqht of Observation Point: 6 feet
Direction of Observer from Discharge Point: SE
Wind Velocity: 3 5 mph
Detached Plume: No
Duration of Observation: 7/9/75 106 minutes
» 7/10/75 60 minutes
Summary of Data:
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
3
0
0
0
or
Opacity
Sec.
0
45
30
0
-
-
Opacity,
Percent
55
60
65
70
75
80
85
90
95
100
Total Time Equal to or
Greater Than Given Opacitv
Min.
Sec.
Sketch Showing How Opacitv Varied With Time:
-ti-
7/9/75
TIME, hours
7/10/75
(1) Two observers made simultaneous readings, the greater of their readings
is reported.
C-19
-------
TABLE M
FACILITY Bl
Summary of Results
Run Number
Date
Test Time - Minutes
(1)
Production Rate - TPH
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature - °F
Water vapor - Vol. %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton.
(1) Throughput through primary crusher.
1
10/29/74
180
324
5154
4998
70
1.80
2
10/30/74
120
359
6121
5896
76
1.87
3
10/30/74
120
375
6078
5753
83
2.06
Avera
-
140
353
5784
5549
76.3
1.91
See Table 12
0.009
0.012
0.402
0.0012
0.009
0.011
0.496
0.0015
0.001
0.004
0.072
0.0002
0.001
0.003
0.180
0.0005
0.010
0.011
0.500
0.0013
0.010
0.011
0.553
0.0015
0.007
0.009
0.325
0.0007
0.007
0.008
0.408
0.0012
C-20
-------
TABLE ]2
FACILITY Bl
Surmary o
.0!
1 ^
Distance from Ovserver to Discharge Point: 15 ft.
Height of Observation Point: Ground level
Direction of Observer from Discharge Point: West
Date: 10/29/74 10/30/74
Type of Plant: Crushed Stone Primary Crusher
Type of Discharge: Stack
Location of Discharge: Baghouse
Height of Point of Discharge: 25 ft.
Description of Background: Grey quarry wall
>•>
Description of Sky: Clear to cloudy
Wind Direction: Northwesterly ... , .. , ., ., . ... ...
J Wind Velocity: Not available
Color, of Plume: White
Detached Plume: No
Duration of Observation: 10/29/74 180 minutes
10/30/74 234 minutes
SUMMARY OF AVERAGE OPACITY
SUMMARY OF AVERAGE OPACITY
Time
Set Number
10/29/74
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Ib
17
18
19
20
2]
22
23
24
2S
26
27
28
29
30
10/30/74
31
J<;
33
Start
10:30
10:36
10:42
10:48
10:54
11:00
11:06
11:12
11:18
11:24
11:30
11:36
11:42
:15
:21
:27
:33
:39
:45
:bl
:57
2:03
2:09
2:lb
2:21
2:27
2:33
2:39
2:45
2:51
9:05
s:h
9:17
End
10:36
10:42
10:48
10:54
11:00
11:06
11:12
11:18
11:24
11:30
11:36
11:42
11:48
1:21
1:27
1:33
1:39
1:45
1:51
1:57
2:03
2:09
2:15
2:21
2:27
2:33
2:39
2:45
2:51
2:57
9:11
a: 1 7
9:23
Opacity
Sum
10
20
25
15
15
5
10
25
20
15
25
30
15
0
15
5
5
0
0
0
5
5
0
0
0
5
5
0
0
10
0
u
0
Average Set Number
0.4
0.8
1.0
0.6
0.6
0.2
0.4
1.0
0.8
0.6
1.0
1.2
0.6
0
0.6
0.2
0.2
0
0
0
0.2
0.2
0
0
0
0.2
0.2
0
0
"0.4
0
u
0
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
- 64
65
66
67
60
69
Time
Start
9:23
9:29
9:35
9:41
9:47
9:53
9:59
10:05
10:11
10:17
10:28
10:34
10:40
10:58
11 : 04
11:10
11:24
11:30
1:02
1:08
1:14
1:20
1:26
1:32
1:38
1:44
1:50
1:56
2:02
2:08
-2:14
2:20
2:26
2:39
Ł. . t J
2:51
End
9:29
9:35
9:41
9:47
9:53
9:59
10:05
10:11
10:17
10:23
TO: 34
10:40
10:46
11:04
11:10
11:16
11:30
11:36
1:08
1:14
1:20
1:26
1:32
1:38
1:44
1:50
1:56
2:02
2:08
2:14
2:2-0
2:26
2:32
2:45
2: 31
2:57
Opacity j
Sum
0
5
10
0
0
5
0
0
0
0
0
10
5
0
5
10
0
0
0
0
0
10
0
5
0
0
0
5
0
5
5
0
0
0
c
0
Average
0
0.2
0.4
0
0
0.2
0
0
0
0
0
0.4
0.2
0
0.2
0.4
0
0
0
0
0
0.4
0
0.2
0
0
0
0.2
0
0.2
0.2
0
0
0
n f\
w . «-
0
C-21
-------
TABLE ]3
FACILITY B2
Summary of Results
Run Number
Date
Test Time - Minutes
Production Rate TPH
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature °F
Water vapor - Vol . %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
1
10/31/74
108
270
19684
18296
92.0
1.95
0.003
0.003
0.427
0.0016
0.006
0.005
0.916
0.0034
2
10/31/74
108
270
18921
17638
96.0
1.92
SEE TABLES
0.005
0.005
0.753
0.0028
0.006
0.006
0.978
0.0036
3
11/11/74
108
270
16487
15681
79.0
2.01
14 - 23
0.003
0.003
0.457
0.0017
0.007
0.007
0.955
0.0035
Average
-
108
270
18197
17205
87.0
1.96
0.0037
0.0037
0.546
0.0020
0.0063
0.0060
0.946
0.0035
C-22
-------
TABLE T4'
FACILITY B2
Summary of visible Emissions
(Observer 1)
Date: 10/31/74 11/1/74
Type of Plant: Crushed Stone Secondary and Tertiary Crushing and Screening
Type of Discharge: Stack Distance from Observer to Discharge Point: 30 ft.
.Location of Discharge: Baghouse Height of Observation Point: 5 ft.
Height of Point of Discharge: 8 ft. Direction of Observer from Discharge Point: East
Description of Background: Sky
Description of Sky: Clear to partly cloudy
Uind Direction: Southeasterly Wind Velocity: Not available
Color of Plume: White Detached Plume: No
i
Duration of Observation: 10/31/74
240 minutes
11/1/74
106 minutes
SUMMARY OF AVERAGE OPACITY
Time Opacity
Date
10/31/74
11/1/74
Set Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21 through
40
41 through
56
Start
9:27
9:33
9:39
9:45
9:51
9:57
10:03
10:09
10:15
10:21
10:27
10:33
10:39
10:45
10:51
10:57
11:03
11:09
11:15
11:21
1:09
8:11
End
9:33
9:39
9:45
9:51
9:57
10:03
10:09
10:15
10:21
10:27
10:33
10:39
10:45
10:51
10:57
11:03
11:09
11:15
11:21
11:27
3:09
9:47
Sum
5
10
5
0
5
5
10
5
20
0
0
0
5
5
10
0
5
0
0
10
0
0
Average
0.2
0.4
0.2
0
0.2
0.2
0.4
0.2
0.8
0
0
0
0.2
0.2
0.4
0
0.2
0
0
0.4
0
0
Readings ranged from 0 to 5 percent opacity.
C-23
-------
FACILITY B2
SUMMARY OF VISIBLE EMISSIONS
Date: 6/30/75
Tyoe of Plant: Crushed stone (limestone)
Type of Discharge: Fugitive
Location of Discharge:Secondary Cone Crusher (#1)
Height of Point of Discharge: 25 ft. Distance from Observer to Discharge Point:45
Oescriotion of Background: Sky & Equipment Height of Observation Point: 2 ft.
Description of Sky: Clear Direction of Observer from Discharge Point:No
Wind Direction: East Wind Velocity: 5-10 mph
Color of Plume: White Detached Plume: No
Duration of Observation: 231 minutes
Summary of Data:
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
23
0
or
Opacity
Sec.
0
45
Opacity,
Percent
55
60
65
70
75
80
85
90
95
100
Total Time Equal to or
Greater Than Given Onac
Min.
Sec
C-24
-------
Table 16
FACILITY B2
SUMMARY OF VISIBLE EMISSIONS
Date: 6/30/75
Tyoe of Plant: Crushed stone (limestone)
Type of Discharge: Fugitive
Location of Discharge: Secondary Cone Crusher ^'
Height of Point of Discharge: 25 ft. Distance from Observer to Discharge Point: 45 ft.
Descriotion of Background: Sky & Equipment Height of Observation Point: 2 ft.
lescrintion of Sky: Clear Direction of Observer from Discharge Point: North
Wind Direction: East Mind Velocity: 5-10 mph
Color of Plume: White Detached Plume: No
Duration of Observation: 231 minutes
Summary of Data:
Qoacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
0
0
or
Opacity
Sec.
15
0
•Opacity, Total Time Equal to or
Percent Greater Than Given Onacitv
Min. Sec.
55
60
65
70
75
80
85
90
95
100
C-25
-------
i ci'j i e | /
FACILITY B2
SUMMARY OF VISIBLE EMISSIONS
Date: 6/30/75
Tyoe of Plant: Crushed stone (limestone)
Type of Discharge: Fugitive
Location of Discharge: Secondary Cone Crusher
Height of Point of Discharge: 25 ft. Distance from Observer to Discharge Point:45
Descriotion of Background: Sky & Equipment Height of Observation Point: 2 ft.
Description of Sky: Clear Direction of Observer from Discharge Point:N
Wind Direction: East Wind Velocity: 5-10 mph
Color of Plume: Nhite Detached Plume: No
Duration of Observation: 231 minutes
Summary of Data:
Ooaclty,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min.Sec.
0
0
Opacity,
Percent
55
60
65
70
75
80
85
90
95
100
Total Time Equal to or
Greater Than Given Onai
Min.
Set
C-26
-------
Table 18
FACILITY B2
SUMMARY OF VISIBLE EMISSIONS
Date: 6/30/75 - 7/1/75
Tyoe of Plant: Crushed stone (limestone)
Type of Discharge: Fugitive
Location of Discharge: Surge Bin
Hsiffit of Point of Discharge: Distance from Observer to Discharge Point:150 ft,
Descriotion of Background: Sky & Equipment Height of Observation Point: 15 ft.
'Inscription of Sky: Clear Direction of Observer from Discharge Point:SE
Mind Direction: South Wind Velocity: 5 mph
Color of Plume: white Detached Plume: No
Duration of Observation: 6/30/74 - 234 minutes
7/1/75 - 53 minutes
Summary of Data
Ooacity,
Percent
5
n
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
2
1
_
-
or
Opacity
Sec.
0
15
30
-
Opacity, Total Time Equal to or
Percent Greater Than Given Onacitv
Min. Sec.
55
60
65
70
75
80
85
90
05
100
C-27
-------
I au I
FACILITY B2
SUMMARY OF VISIBLE EMISSIONS
Date: 6/30/75 - 7/1/75
Tyoe of Plant: Crushed stone (limestone)
Type of Discharge: Fugitive
Location of Discharge: Scalp'ing screen
Height of Point of Discharge: 50 ft. Distance from Observer to Discharge Point:15(
Descriotion of Background: Sky & Equipment Height of Observation Point: 15 ft.
Description of Sky: Clear Direction of Observer from Discharge Point: j
Wind Direction: South Wind Velocity: 5 MPH
Color of Plume: White Detached Plume: no
Duration of Observation: 6/30/75 - 234 minutes
7/1/75 - 53 minutes
Summary of Data:
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
44
9
3
0
-
or
Opacity
Sec.
45
45
0
30
-
Opacity, Total Time Equal to or
Percent Greater Than Given Onai;
Min. Sec
55
65
70
75
80
85
90
95
100
C-28
-------
Table 20
FACILITY B2
SUMMARY OF VISIBLE EMISSIONS
ate: 6/30/75 - 7/1/75
yoe of Plant: Crushed stone (limestone)
Yoe of Discharge: Fugitive
.ocation of Discharge: Hammer-mill
tein'it of Point of Discharge: Distance from Observer to Discharge Point: 150 ft,
lescriotion of Background: Sky & Equipment Height of Observation Point: 15 ft.
fescrintion of Sky: Clear Direction of Observer from Discharge Point:SE
lind Direction: South Wind Velocity: 5 mph
;olor of Plume: White Detached Plume: No
luration of Observation: 6/30/75 - 234 minutes
7/1/75 - 53 minutes
Summary of Data:
Ooacity, Total Time Equal to or Opacity, Total Time Equal to or
Percent Greater Than Given Opacity Percent Greater Than Given Opacity
Min.Sec.Min. Sec.
500 55
10- _ 60
15 65
20 70
25 75
30 80
35 85
40 90
45 95
50 100
C-29
-------
i o'j 11-; ^|
FACILITY B2
SUMMARY OF VISIBLE EMISSIONS
Date: 7/1/75
Tyoe of Plant: Crushed stone (limestone)
Type of Discharge: Fugitive
Location of Discharge: (3-Deck) Finishing Screen (left)
Height of Point of Discharge: 40 '
Descriotion of Background: Hazy Sky
Description of Sky: Clear
Wind Direction: Southeast
Color of Plume: White
Duration of Observation: 107 minutes
Distance from Observer to Discharge Point:75
Height of Observation Point: Ground level
Direction of Observer from Discharge Point:
Wind Velocity: 5-15 mph
Detached Plume: No
Summary of Data:
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min.Sec.
4 30
Opacity,
Percent
55
60
65
70
75
80
85
90
%
100
Total Time Equal to or,
Greater Than Given Ona
Ml n . Se
C-30
-------
Table 22
FACILITY B2
SUMMARY OF VISIBLE EMISSIONS
Date: 7/1/75
Tyne of Plant: Crushed stone (limestone)
Tyne of Discharge: Fugitive
Location of Discharge: (3-Dec'k) Finishing screen (right)
llsiq'it of Point of Discharge: 40 ft.
Oescriotion of Background: Hazy sky
Ascription of Sky: Clear
!>lind Direction: Southeast
Color of Plume: White
Duration of Observation: 107 minutes
Distance from Observer to Discharge Point: 75 ft.
Height of Observation Point: Ground level
Direction of Observer from Discharge Point: West
Wind Velocity: 5-15 mph
Detached Plume: No
Summary of Data:
Onacit.y,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min.~Sec.
0
15
Opacity,
Percent
55
60
65
70
75
80
85
90
%
100
Total Time Equal to or
Greater Than Given Onacitv
Min.
Sec.
C-3T
-------
FACILITY B2
SUMMARY OF VISIBLE EMISSIONS
Date: 6/30/75
Tyoe of Plant: Crushed stone (limestone)
Type of Discharge: Fugitive
Location of Discharge: Two (3-Deck) finishing screens
Height of Point of Discharge: 50 ft.
Descriotion of Background: Hazy sky
Description of Sky:Clear
Wind Direction: Southeast
Color of Plume: White
Duration of Observation: 120 minutes
Summary of Data:
Distance from Observer to Discharge Point: 75
Height of Observation Point:Ground level
Direction of Observer from Discharge Point:We
Wind Velocity: 10-15 mph
Detached Plume:No
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
86
28
5
0
0
_
or
Opacity^
Sec.
15
15
30
15
0
_
Opacity,
Percent
55
<50
65
70
75
80
85
90
95
100
Total Time Equal to or
Greater Than Given Ooac
Mi n . Sec
C-32
-------
Run Number
Date
Test Time Minutes
Production Rate - TPH
Stack Effluent
Flow rate - ACFM
Flow rate DSCFM
Temperature - °F
Water Vapor - Vol. %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
0)
TABLE 2'4
FACILITY B3
Summary of Results
1
10/31/74
270
11/1/74
270
3
11/1/74
270
Average
270
18674
17335
92
2.13
0.002
0.002
0.355
0.0013
18405
17186
90
1.73
0.004
0.004
0.614
0.0023
16238
15466
79
1.87
0.003
0.003
0.411
0.0015
17772
16662
87
1.91
0.003
0.003
0.460
0.0017
(1)
No analysis of bark-half on in-stack filter tests.
C-33
-------
Run Number
Date
Test Time - Minutes
TABLE 25
FACILITY Cl
Sunmary of Results
1 2 3 Average
11/19/74 11/21/74 11/22/74
(1)
120
Production Rate - TPH
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature - °F
ulater vapor - Vol. %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF_
Ib/hr
Ib/ton
Total catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
(1) Throughput through primary crusher.
240
240
200
7340
7250
66.0
1.0
0.003
0.003
0.18
0.001
0.007
0.007
0.43
0.003
7560
7720
38.0
0.4
See table
0.0007
0.0007
0.05
0.0004
0.001
0.001
0.09
0.0008
7520
7800
44.0
0.1
26
0.003
0.003
0.17
0.001
0.003
0.003
0.21
0.002
7473
7593
49.3
0.5
0.0022
0.0022
0.10
0.0008
0.0037
0.0037
0.24
0.0019
C-34
-------
TABLE 26
FACILITY Cl
Summary of Visible Emissions
(1)
Date: 11/21/74
Type of Plant: Crushed Stone Primary and Secondary Crushing and Screening
Type of Discharge: Stack
Location of Discharge: Baghouse
Height of Point of discharge: 40 ft.
Description of Background: Dark Woods
Description of Sky: Overcast
Wind Direction: Easterly
Color of Plume: White
Duration of Observation: 240 minutes
Distance from Observer to Discharge Point: 100 ft,
Height of Observation Point: 50 ft.
Direction of Observer from Discharge Point: N.W.
Wind Velocity: 10 to 30 mi/hr.
Detached Plume: No
SUMMARY OF AVERAGE OPACITY
Time
(2)
Opacity
Set Number
Start
End
Sum
Average
1 through 40 12:10 4:10 °
Readings were 0 percent opacity during the observation period.
Sketch Showing How Opacity Varied With Time:
0)
o
i-
01
CL
O
to
O-
o
J_
(1)
3 4
Time, hours
Two observers made simultaneous readings.
Reference 5.
C-35
-------
Run Number
Date
Test Time - Minutes
TABLE : 27
FACILITY C2
Summary of Results
1 2 3 Average
11/19/74 11/21/74 11/22/74
0)
Production Rate - TPH
Stack Effluent
Flow rate - ACFH
Flow rate - DSCFM
Temperature - °F
Water vapor - Vol. %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
(1) Throughput through primary crusher.
120
132
6220
6260
62.0
0.4
0.006
0.006
0.31
0.002
0.008
0.009
0.46
0.003
240
119
6870
6880
50.0
0.3
See Table
240
127
6540
6700
51.0
0.1
"28
0.00003 0.0004
0.00003
0.002
0.00002
0.0006
0.0007
0.04
0,0003
0.004
0.02
0.0002
0.0009
0.001
0.05
0.0004
200
126
6543
6613
54.3
0.27
0.00214
0.00214
o.m
0.00074
0.0032
0.0057
•0.18
0.0012
C-36
-------
IrtDLC. Zti
FACILITY C2
rf I O I U I f
jate: 11/21/74
'ype of Plant: Crushed Stone - Finishing Screens
!ype of Discharge: Stack
iOcation of Discharge: Baghouse
eight of Point of Discharge: 40 ft.
inscription of Background: Dark woods
iescription of Sky: Overcast
find Direction: Easterly
lolor of Plume: White
Duration of Observation: 240 minutes
Distance from Observer to Discharge Point: 200 f
Height of Observation Point: 50 ft.
Direction of Observer from Discharge Point: N.W.
Wind Velocity: 10 to 30 mi/hr.
Detached Plume:
SUMMARY OF AVERAGE OPACITY
Time
Set Number
Opacity
Start
End
Sum
Average
1 through 40 12:10 4:10 0
Readings were 0 percent opacity during the observation period.
ketch Showing How Opacity Varied With Time:
c
-------
Run Number
Date
TABLE 29
FACILITY Dl
Summary of Results
.»
123 Average
9/17/74 9/18/74 9/19/74
Test Time - Minutes
Production Rate - TPH*1'
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature - °F
Water vapor - Vol . %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
240
225
31830
31370
66.0
1.2
0.0095
0.0094
2.55
0.0113
0.0100
0.0096
2.69
G.0120
240
230
31810
30650
71.0
1.7
SEE TABLES
0.0081
0.0078
2.13
0.0093
0.0085
0.0082
2.23
0.0097
240
220
31950
31230
68.0
1.6
30-36
0.0080
0.0078
2.13
0.0097
0.0086
0.0084
2.30
0.0105
240
225
31863
31083
68.3
1.5
0.0085
0.0083
2.27
0.0101
0.0090
0.0088
2.41
0.107
(1) Throughput through primary crusher.
C-38
-------
TABLE 30
FACILITY Dl
Summary of Visible Emissionsv '
uate: 9/17/74
Type of Plant: Crushed Stone Secondary and Tertiary Crushing & Screening
Type of Discharge: Stack
Location of Discharge: Baghouse
Height of Point of Discharge: 55 ft.
Description of Background: Trees
Description of Sky: Partly Cloudy
Wind Direction: Northerly
*
Color of Plume: None
Duration of Observation: 240 minutes
Distance from Observer to Discharge Point: 300 ft.
Height of Observation Point: 40 ft.
Direction of Observer from Discharge Point: S.E.
Wind Velocity: 5 10 mi/hr.
Detached Plume: No
Set Number
SUMMARY OF AVERAGE OPACITY(2)
Time Opacity
Start End Sum Average
1 through 40 9:10 1:00 0 0
Readings were 0 percent opacity during the period of observation.
Sketch Snowing How Opacity Varied With Time:
S.
O-
o
I
I
3- 4
Time, hours
C-39
-------
taoie 3i
FACILITY Dl
SUMMARY OF VISIBLE EMISSIONS
Date: 7/8/75
Tyoe of Plant: Crushed stone (traprock)
Type of Discharge: Fugitive
Location of Discharge: Terti'ary gyrasphere cone crusher (S)
of Point of Discharge:
Description of Background: Machinery
Description of Sky: Overcast
Wind Direction: Southwest
Color of Plume: White
Duration of Observation: 170 minutes
Distance from Observer to Discharge Point:
Heipht of Observation Point: ground level
Direction of Observer from Discharge Point:
Wind Velocity: 0-10 mph
Detached Plume: No
Summary of Data
Ocacity,
Percent
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opaci ty
Min.Sec.
0
Opacity,
Percent
55
60
65
70
75
80
85
90
95
100
Total Time Equal to oral},
Greater Than Given Onarat
Min.
Se
C-40
-------
I 3D If? 32
FACILITY Dl
SUMMARY OF VISIBLE EMISSIONS
ite: 7/8/75
^oe of Plant: Crushed stone (traprock)
ype of Discharge: Fugitive
ocation of Discharge: Tertiary gyrashere cone crusher (N)
of Point of Discharge:
escriotion of Background: Machinery
escrintion of Sky: Overcast
ind Direction: Southwest
;olor of Plume: White
luration of Observation: -\JQ minutes
Distance from Observer to Discharge Point: 30 ft.
Height of Observation Point: ground level
Direction of Observer from Discharge Point: West
Wind Velocity: 0-10 mph
Detached Plume: NO
ummary of Data:
Ooacity,
Percent
5
n
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Mi n. : Sec.
0
0
Opacity,
Percent
55
60
65
70
75
80
85
90
%
100
Total Time Equal to or
Greater Than Given Onacitv
Min.
Sec.
C-41
-------
lab IP 33
FACILITY Dl
SUMMARY OF VISIBLE EMISSIONS
Date: 7/8/75
Tyoe of Plant: Crushed stone (traprock)
Type of Discharge: Fugitive
Location of Discharge: secondary standard cone crusher
Height of Point of Discharge:
Oescriotion of Background: Machinery
Description of Sky: Overcast
Wind Direction: Southwest
Color of Plume: Mhite
Duration of Observation: 170 minutes
Distance from Observer to Discharge Point: 30
Height of Observation Point: Ground level
Direction of Observer from Discharge Point:We
Wind Velocity: 0-10 mph
Detached Plume: No
Summary of Data:
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min.Sec.
0
0
Opacity, Total Time Equal to orj,
Percent Greater Than Given Qpaq,
Min. Ser
55
W
65
70
75
80
85
90
05
100
C-42
-------
Table 34
FACILITY Dl
SUMMARY OF VISIBLE EMISSIONS
Date: 7/9/75
jyoe of Plant: Crushed stone (traprock)
Type of Discharge: Fugitive
Location of Discharge: Scalp'ing screen
Height of Point of Discharge:
Descriotion of Background: Equipment
"tescrintion of Sky: Overcast
Wind Direction: Southwest
Color of Plume: white
Duration of Observation: 210 minutes
Summary of Data:
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Distance from Observer to Discharge Point: 30 ft.
Height of Observation Point: 15 ft.
Direction of Observer from Discharge Point: North
Wind Velocitv: 0-10 mph
Detached Plume: No
Total Time Equal to or
Greater Than Given Opacity
WnT
Sec.
Opacity,
Percent
55
W
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Onacitv
Min.
Sec.
C-43
-------
ici'jie 35
FACILITY Dl
SUMMARY OF VISIBLE EMISSIONS
Date: 7/9/75
Tyoe of Plant: Crushed stone (traprock)
Type of Discharge: Fugitive
Location of Discharge: Secondary (2-Deck) sizing screens
Height of Point of Discharge:
Description of Background: Equipment
Description of Sky: Overcast
Wind Direction: Southwest
Color of Plume: White
Duration of Observation: 210 minutes
Distance from Observer to Discharge Point: ;
Height of Observation Point: 15 ft. ;
Direction of Observer from Discharge Point::
Wind Velocity: 0-10 mph
Detached Plume: No
Summary of Data:
Opacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min. Sec.
0
0
Opacity,
Percent
55
60
65
70
75
80
85
90
05
TOO
Total Time Equal to o\
Greater Than Given OD;,
Min.
S<
C-44
-------
lab In 36
FACILITY Dl
SUMMARY OF VISIBLE EMISSIONS
late: 7/9/75
•yne of Plant: Crushed stone (traprock)
[yne of Discharge: Fugitive
.ocation of Discharge: Secondary (3-Deck) sizing screens
feiq'nt of Point of Discharge:
Jescriotion of Background: Equipment
fecriotion of Sky: Overcast
Hind Direction: Southwest
Color of Plume: white
Duration of Observation: 210 minutes
Distance from Observer to Discharge Point: 30 ft
Height of Observation Point: 15 ft.
Direction of Observer from Discharge Point: North
Wind Velocity: 0-10 mph
Detached Plume: No
Summary of Data:
Ooacity,
Percent
5
n
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Mi n.
0
Sec.
0
Opacity,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Onacitv
Min.
Sec.
C-45
-------
Run Number
Date
TABLE 37
FACILITY D2
Sunmary of Results
1 2 3
9/17/74 9/18/74 9/19/74
Average
Test Time - Minutes
Production Rate - TPH^
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature - °F
Water vapor - Vol. %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
240
225
26790
26200
69.0
1.3
0.0027
0.0027
0.61
0.0027
0.0041
0.0040
0.91
0.0040
240
230
26260
25230
74.0
1.6
See Table
0.0038
0.0036
0.82
0.0036
0.0045
0.0043
0.98
0.0043
240
220
24830
24170
72.0
1.3
38
0.0023
0.0022
0.47
0.0021
0.0031
0.0030
0.64
0.0029
240
225
25960
25200
71.7
1.4
0.0029
0.0028
0.63
0.0028
0.0039
0.0038
0.84
0.0037
(1) Throughput through primary crusher.
C-46
-------
Run Number
Date
TABLE 39
FACILITY El
Summary of Results
1 2 3
11/18/74 11/18/74 11/19/74
Average
Test Time - Minutes
Production Rate - TPH^
Stack Effluent
Flow rate - ACFM
Flow rate DSCFM
Temperature - °F
Water vapor - Vol . %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF"
Ib/hr
Ib/ton
Total catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
120
384
15272
16297
33.1
0.5
0.0134
0.0143
1.87
0.0049
i 0.0170.
0.0181
2.37
0.0067
120
342
13997
14796
40,4
0.0
SEE TABLE
0.0116
0.0122
1.47
0.0043
0.0137
0.0145
1.74
0.0051
120
460
14975
15642
41.0
0.5
40
0.0147
0.0154
1.97
0.0043
0.0164
'0.0171.
2.20 .
0.0048
120
395
14748
15578
38.2
0.3
0.0132
0.0140
1.77
0.0045
0.0157
0.0166
2.10
0.0055
(1) Throughput through primary crusher.
C-47 a
-------
FACILITY D2
Summary of Visible Emissions
(1)
Late: 9/18/74
Type of Plant: Crushed Stone - Finishing Screens
Type of Discharge: Stack
Location of Discharge: Baghouse
Height of Point of Discharge: 55 ft.
[Description of Background: Trees
Description of Sky: Clear
Wind Direction: Northerly
Color of Plume: None
Duration of Observation: 240 minutes
Distance from Observer to Discharge Point: 300 ft.
Height of Observation Point: 40 ft.
Direction of Observer from Discharge Point: North
Wind Velocity: 5 to 10 mi/hr.
Detached Plume: No
(2)
Set Number
SUMMARY OF AVERAGE OPACITY
Time Opacity
Start End SumAverage
1 through 40 8:30 12:30 0
Readings were 0 percent opacity during period of observation.
Sketch Showing How Opacity Varied with Time:
c
Ol
o
U
-------
TABLE 40
FACILITY El
Summary cf Visible Err,-;53Ions '
Date: 11/18/74 - 11/19/74
Type of Plant: Crushed Stone - Tertiary Crushing and Screening
Type of Discharge: Stack Distance from Observer to Discharge Point: 60 ft.
Location of Discharge: Baghouse Height of Observation Point: Ground level
Height of Point of Discharge: 1/2 ft. Direction of Observer from Discharge Point: South
Description of Background: Grey Wall
Description of Sky: Overcast
Wind Direction: Westerly Wind Velocity: 2-10 mi/hr.
Color of Plume: None Detached Plume: No
Duration of Observation: 11/18/74 - 120 minutes
11/19/74 - 60 minutes
SUMMARY OF AVERAGE OPACITY
Time Opacity
Set Number
11/18/74
1 through 10
11 through 20
11/19/74
21 through 30
Start
9:00
10:15
10:07
End
10:00
11:15
11:07
Sum
0
0
0
Average
0
0
0
Readings were 0 percent opacity during all periods of observation.
Sketch Snowing How Opacity Varied With Time:
C-48
-------
Run Number
Date
TABLE 41
FACILITY E2
Summary of Results
1 2 3
11/18/74 11/18/74 11/19/74
Average
Test Time - Minutes
(1)
Production Rate - TPH
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature - °F
Water vapor - Vol. %
Visible Emissions at
Collector Discharge -
% Opacity
Particulate Emissions
Probe and filter catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
(1) Throughput through primary crusher.
.120
384
22169
23001
1 44.5
1.1
0.0132
0.0137
2.60
0.0068
0.0205
0.0213
4.05
0.0105
120
342
19772
19930
59.2
1.1
SEE TABLE
0.0096
0.0097
1.65
0.0048
0.1378
0.0139
2.35
0.0069
120
460
21426
21779
55.0
0.6
42
0.0153
0.0155
2.85
0.0062
0.0170
0.0173
. 3.18
0.0069
120
395
21122
21570
52.9
0.9
0.0127
0.0130
2.37
0.0059
0.0171
0.0175
3.19
0.0081
C-49
-------
TABLE 42
FACILITY E2
Summary of Visible Emissions
Date: 11/16/74 - 11/19/74
Type of Plant: Crushed Stone - Finishing Screens and Bins
Type of Discharge: Stack Distance from Observer to Discharge Point:
Location of Discharge: Baghouse Height of Observation Point: Ground level
Height of Point of Discharge: 1/2 ft. Direction of Observer from Discharge Point:
Description of background: Hillside
Description of Sky: Clear
Wind Direction: Westerly Wind Velocity: 2-10 mi/hr.
Color of Plume: None Detached Plume: No
Duration of Observation: 11/18/74 - 120 minutes
11/19/74 - 60 minutes
SUMMARY OF AVERAGE OPACITY
(2)
Time
Set Number
11/18/74
1 through 10
11 through 20
11/19/74
21 through 30
Start
12:50
1:50
9:05
End
1:50
2:00
10:05
Opacity
Sum
0
0
0
Average
0
0
0
Readings were 0 percent opacity during all periods of observation.
Sketch Showing How Opacity Varied With Time:
C-50
-------
Tabln 43
FACILITY F
SUMMARY OF VISIBLE EMISSIONS
bte: 8/26/76
fyoe of Plant: Crushed stone (traprock)
type of Discharge: Fugitive
location of Discharge: TWO tertiary crushers (#4 and #5)
Height of Point of Discharge: #4-20 ft. Distance from Observer to Discharge Point: 100 ft
#5-10 ft.
iescriotion of Background: Gray equipment Height of Observation Point: ground level
Structures
P'scriotion of Sky: Partly cloudy Direction of Observer from Discharge Point: West
Kind Direction: Variable
Color of Plume: No visible plume
puration of Observation: 65 minutes
Wind Velocity: 0-5 mph
Detached Plume:
luminary of Data:
Ooacity,
Percent
5
n
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min. Sec.
0
0
Opacity,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Onacitv
Min.
Sec.
C-51
-------
table 44
FACILITY F
SUMMARY OF VISIBLE EMISSIONS
Date: 8/26/76
Tvoe of Plant: Crushed stone (traprock)
Type of Discharge: Fugitive
Location of Discharge: Four processing screens
Height of Point of Discharge: 50 ft.
Oescriotion of Background:gray walls
Description of Sky: Partly cloudy
Wind Direction: Variable
Color of Plume: NO visible plume
Duration of Observation: 180 minutes
Distance from Observer to Discharge Point: 10
Height of Observation Point: ground level
Direction of Observer from Discharge Point: N
Wind Velocity: 0-5 mph
Detached Plume:
Summary of Data:
Opacity,
Percent
Total Time Equal to or
Greater Than Given Opacity
Min.Sec.
5
10
15
20
25
30
35
40
45
50
0
0
Opacity, Total Time Equal to or
Percent Greater Than Given Onac
55
60
65
70
75
80
85
90
15
100
Min.
Sec
C-52
-------
iciuio 45
FACILITY F
SUMMARY OF VISIBLE EMISSIONS
fete: 8/27/76
tyoe of Plant: Crushed stone (traprock)
Type of Discharge: Fugitive
tocation of Discharge: conveyor transfer points
light of Point of Discharge: 75 ft. Distance from Observer to Discharge Point: 150 ft
OescriDtion of Background: Gray equipment Height of Observation Point: 50 ft.
structures
Inscription of Sky: Overcast Direction of Observer from Discharge Point: SE
Hind Direction: Variable, S-SE
Color of Plume: No visible plume
Duration of Observation: 179 minutes
Wind Velocity: 0-10 mph
Detached Plume:
Summary of Data:
Ooacity,
Percent
5
n
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Mi n. Sec.
0
0
Opacity,
Percent
55
60
65
70
75
80
85
90
95
100
Total Time Equal to or
Greater Than Given Onacitv
Min.
Sec.
C-53
-------
Tab!ft'46
FACILITY Gl
SUMMARY OF VISIBLE EMISSIONS
Date: 9/27/75
Tyoe of Plant: Feldspar
Type of Discharge: Fugitive
Location of Discharge: Primary Crusher
Height of Point of Discharge: 10-30 ft. Distance from Observer to Discharge Point:
Descriotion of Background: Quarry wall & Height of Observation Point: Ground level
equipment structures
Description of Sky: Partly cloudy Direction of Observer from Discharge Point:
Mind Direction: Northeast
Color of Plume:
Duration of Observation: 60 minutes
Wind Velocity: 0-10 mph
Detached Plume: No
Summary of Data:
Ooacit.y,
Percent
5
11
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
WnT
Sec.
45
Opacity,
Percent
55
60
65
70
75
80
85
90
Q5
100
Total Time Equal to o»
Greater Than Given OK
Min.
Sf
C-54
-------
Table 47
FACILITY Gl
SUMMARY OF VISIBLE EMISSIONS
ate: 9/27/76
yoe of Plant: Feldspar
y0e of Discharge: Fugitive
ocation of Discharge: Conveyor transfer point (#1)
of Point of Discharge: 10 ft.
lescriotion of Background: Quarry wall
l»scriDtion of Sky: Overcast
rind Direction: Northeast
olor of Plume: No plume
(oration of Observation: 80 minutes
Distance from Observer to Discharge Point:50 ft.
Height of Observation Point: ground level
Direction of Observer from Discharge Point: SE
Wind Velocity: 0-5 mph
Detached Plume: No
mmary of Data
Ooacity,
Percent
5
n
15
29
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min.
Sec.
Opacity,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Onacitv
Mi n.
Sec.
C-55
-------
Table 48
FACILITY G1
SUMMARY OF VISIBLE EMISSIONS
Date: 9/27/76
Tyoe of Plant: Feldspar
Type of Discharge: Fugitive
Location of Discharge: Conveyor transfer point (#2)
Height of Point of Discharge: 40 ft. Distance from Observer to Discharge Point: 5
Description of Background: Quarry wall Height of Observation Point: ground level
Oescrintion of Sky: Partly cloudy-Overcast Direction of Observer from Discharge Point: S
Wind Direction: North-northwest Wind Velocity: 0-10 mph
Color of Plume: No plume Detached Plume: N/A
Duration of Observation: 87 minutes
Summary of Data:
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min.Sec.
0
0
•Opacity, Total Time Equal to or
Percent Greater Than Given Onac
55
60
65
70
75
80
85
90
Q5
100
Min.
Set
C-56
-------
Table 49
FACILITY Gl
SUMMARY OF VISIBLE EMISSIONS
Date: 9/27/76
jyoe of Plant: Feldspar
Tyoc of nischarge:Fugitive
Location of Discharge: Secondary crusher
||sif|ht of Point of Discharge: 10-20 ft. Distance from Observer to Discharge Point: 75 ft
tocriotiort of Background: Equipment Height of Observation Point: 75 ft
structure
tecrintion of Sky: Partly cloudy -cloudy Direction of Observer from Discharge Point:$SE
Wind Direction: Northwest
Color of Plume: No visible plume
Duration of Observation: 1 hour
Wind Velocity: 0-7 mph
Detached Plume: N/A
Summary of Data:
Ooacity,
Percent
5
n
15
20
25
30
35
40
45
50
Total Time Equal to or
fareater Than Given Opacity
Tlin. Sec.
0
0
Opacity,
Percent
55
60
65
70
75
80
35
90
95
100
Total Time Equal to or
Greater Than Given Onacitv
Min.
Sec.
C-57
-------
50
FACILITY 61
SUMMARY OF VISIRLE EMISSIONS
Date: 9/27/76
Tyoe of Plant: Feldspar
Type of Discharge: Fugitive
Location of Discharge: Conveyor transfer Point (#4)
Height of Point of Discharge: 10 ft.
Distance from Observer to Discharge Point: 84
Description of Background: cliff or wall Height of Observation Point: 75 ft.
Description of Sky: cloudy
Wind Direction: North
Color of Plume: No visible plume
Duration of Observation: 84 minutes
Direction of Observer from Discharge Point: SI
Wind Velocity: 0-7 mph
Detached Plume: N/A
Summary of Data:
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min.Sec.
0
0
Opacity,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Onac
Min.
Sec
C-58
-------
Run Number
Date
Test Tirne-minutes
Production rate - TPH
Stack Effluent
Flow rate - ACFM
Flow rate - DSCFM
Temperature - °F
Water vapor - Vol.%
Visible Emissions at
Collector Discharge -
Percent Opacity
Particulate Emissions
Table 51
FACILITY G2
Summary of Results
}
9/28/76
120
5070
4210
105
2
9/28/76
120
4830
3940
115
3
9/29/76
120
4470
3720
103
Average
120
4790
3960
108
See Tables 52 - 61
Probe and Filter Catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Total Catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
0.005
0.004
0.17
0.005
0.004
0.17
0.005
0.004
0.18
0.005
0.004
0.18
0.004
0.004
0.14
0.004
0.004
0.14
0.005
0.004
0.16
0.005
0.004
0.16
C-59
-------
FACILITY G2
Summary of Visible Emissions
Date: 9/28/76
Type of Plant: Feldspar
Type of Discharge: Outlet Stack
Location of Discharge: No.2 Mill Baghouse
Height of Point of Discharge:100'
Description of Background: trees on hillside
Description of Sky: Overcast
Wind Direction: NW
Color of Plume: No visible plume
Duration of Observation: 2-1/4 hours
SUMMARY OF AVERAGE OPACITY
Distance from Observer to Discharge Point:
Approx. 40'
Height, of Observation Point:
Approx. 100'
Direction of Observer from Discharge Point
Wind Velocity: 0-10 mi/hr
Detached Plume: N/A
SUMMARY OF AVERAGE OPACITY
Opacity
Time
lime
Opacity
Set Number Start End Sum Average Set Number Start End Sum Averau
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20 -.. '
09:48
09:54
10:00
10:06
10:12
10:18
10:24
10:30
10:36
10:42
10:48
10:54
11:00
11:06
11:12
11:18
11:24
11:30
11:36
11:42
09:54
10:00
10:06
10:12
10:18
10:24
10:30
10:36
10:42
10:48
10:54
11:00
11:06
11:12
11:18
11:24
11:30
11:36
11:42
11:48
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
11:48 11:54 N -. N
11:54 12:00 N N
12:00 12:06 N N
Sketch Showing How Opacity Varied With Time:
cu
u
i.
QJ
CX
C-60
-------
I ABLE 53
FACILITY G2
Summary of Visible Emissions
late: 9/29/76
jype of Ficirit: Feldspar
jype of Discharge: Outlet Stack
location of Discharge: No.2 Mill Baghouse
eight of Point of Discharge: 1°°'
Inscription of Background: hillside with trees
Ascription of Sky: Cloudy
Hind Direction: NE Wind Velocity: 0-5 mi/hr
Jolor of Plume: No visible plume Detached Plume: N/A
Duration of Observation: 2 hrs.
SUMMARY OF AVERAGE OPACITY SUMMARY OF AVERAGE OPACITY
Distance from Observer to Discharge Point:
approx. 50'
Height, of Observation Point:
same level as discharge
Direction of Observer from Discharge Point:
Time
Opacity
Time
Opacity
It Number Start End
Sum
Average Set Number Start
End
Sum Average
1
2
3
4
5
6
7
8
'9
10
11
12
13
14
15
16
17
18
19
20
08:35
08:41
08:47
08:53
08:59
09:05
09:11
09:17
09:23
09:29
09:35
09:41
09:47
09:53
09:59
10:05
10:11
10:17
10:23
10:29
08:40
08:46
08:52
08:58
09:04
09:10
09:16
09:22
09:28
09:34
09:40
09:46
09:52
09:58
10:04
10:10
10:16
10:22
10:28
10:34
N
N
M
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
21 10:35 10:37 N N
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Snowing How Opacity Varied With Time:
-M
C
O)
u
t-
O)
O.
C-61
-------
IMDLL 54
FACILITY 62
Summary of Visible Emissions
Date: 9/28/76
Type of Plant: Feldspar
Type of Discharge: Outlet Stack
Location of Discharge: No..2 Mill Baghouse
Height of Point of Discharge: 100'
Description of Background: grassy hillside
Description of Sky: partly cloudy
Wind Direction: NW
Color of Plume: No visible plume
Duration of Observation: approx. 2-1/4 hrs.
SUMMARY OF AVERAGE OPACITY
Distance from Observer to Discharge Point:
Approx. 40' SE
Height, of Observation Point: Approx. 100'
Direction of Observer from Discharge Point:
Wind Velocity: 0-15 mi/hr
Detached Plume: N/A
SUMMARY OF AVERAGE OPACITY
Opacity
Opacity
Time
lime
Set Number Start End
Sum
Average Set Number Start End Sum Average
1
2
3
4
5
6
7
8
"9
10
11
12
13
14
15
16
17
18
19
20 - . '
14:48
14:54
15:00
15:06
15:12
15:18
15:24
15:30
15:36
15:42
15:48
15:54
16:00
16:06
16:12
16:18
16:24
16:30
16:36
16:42
14:54
15:00
15:06
15:12
15:18
15:24
15:30
15:36
15:42
15:48
15:54
16:00
16:06
16:12
16:18
16:24
16:30
16:36
16:42
L6:43
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
\j\j
37
v/ /
38
39
40
16:48 16:54 N .. N
16:54 17:00 N N
Sketch Showing How Opacity Varied With Time:
c
O)
OJ
OL
C-62
-------
Table 55
FACILITY G2
SUMMARY OF VISIBLE EMISSIONS
Date: 9/28/76
Tyi,e of Plant: Feldspar
Vpe of Discharge: Fugitive
Location of Discharge: Ball mill (feed end)
Height of Point of Discharge: 20 ft.
Descrintion of Background: Building &
Equipment
Itecrintion of Sky: N/A
Wind Direction: N/A
Color of Plume: No visible plume
Duration of Observation: 1 hour
Distance from Observer to Discharge Point: 35 ft.
Height of Observation Point:
Direction of Observer from Discharge Point: N/A
Wind Velocity: N/A
Detached Plume:
Summary of Data:
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min.
Sec.
Onacitv,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Onacitv
Min.
Sec.
C-63
-------
Table 56
FACILITY G2
SUMMARY OF VISIBLE EMISSIONS
Date: 9/28/76
Tyoe of Plant: Feldspar
Type of Discharge: Fugitive
Location of Discharge: Ball mill (discharge end)
of Point of Discharge: 20 ft.
Description of Background: Building and
equipment
Description of Sky: N/A
Wind Direction: N/A
Color of Plume: NO visible plume
Duration of Observation: i hour
Distance from Observer to Discharge Point: 3
Height of Observation Point:
Direction of Observer from Discharge Point:
Wind Velocity: N/A
Detached Plume: N/A
Summary of Data:
Opacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
fTin. Sec.
0
0
-Opacity,
Percent
55
60
65
70
75
80
85
90
95
100
Total Time Equal to or
Greater Than Given Onac
Min.
Sec
C-64
-------
Table 57
FACILITY Q2
SUMMARY OF VISIBLE EMISSIONS
: 9/28/76
/
e of Plant: Feldspar
lyoe of Discharge: Fugitive
Location of Discharge: indoor transfer point (#1)
Height of Point of Discharge:
Distance from Observer to Discharge Point:
tocriotion of Background: Building wall Height of Observation Point:
tecn'ntion of Skv: N/A
Hind Direction: N/A
Color of Plume: NO visible plume
Oration of Observation: i hour
Direction of Observer from Discharge Point:
Wind Velocity: N/A
Detached Plume:N/A
Summary of Data:
Ooacity,
Percent
5
n
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min.
Sec.
Opacity,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Onacitv
Min.
Sec.
C-65
-------
Table 58
FACILITY 62
SUMMARY OF VISIBLE EMISSIONS
Date: 9/28/76
Tyoe of Plant: Feldspar
Type of Discharge: Fugitive
Location of Discharge: Indoor transfer point (#2)
Height of Point of Discharge:
Distance from Observer to Discharge Point:
Oescriotion of Background: Building wall Height of Observation Point:
Description of Sky: N/A
Wind Direction: N/A
Color of Plume: No visible plume
Duration of Observation: 1 hour
Direction of Observer from Discharge Point:
Wind Velocity: N/A
Detached Plume: N/A
Summary of Data
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Hi n. Sec.
0
0
•Opacity,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Onac
Min.
Sec
C-66
-------
T.ible59
FACILITY G2
SUMMARY OF VISIBLE EMISSIONS
Date: 9/28/76
Tyiin of I'l ant: Feldspar
jyof! of Discharge: Fugitive
Local ion of Discharge: Indoor Bucket Elevator
of Coin!: of Discharge:
Distance from Observer to Discharge Point:'
i)(jscrii>l:iun of Background: Building walls Height of Observation .Point:
'Kcrintion of Skv: N/A
'•I in-! Hi roc I. ion: N/A
Color of Plume: NO visible plume
Duration of Observation: 1 hour
Direction of Observer from Discharge Point: N/A
Wind Velocity: N/A
Detached Plume: N/A
ary of Data:
On.ic i ty,
P"rcen t
n
30
3S
40
45
50
Total Time Equal to or
Greator Than Given_C)p_a
—-f^ —
0
Sec.
0
-Onaci t.v
Percent
55
60
65
70
75
80
85
90
95
100
, Total Time Equal to or
Grea I.er Jh a n Given Onac i_ty
Min. Sec.
C-67
-------
FACILITY G2
SUMMARY OF VISIBLE EMISSIONS
Date: 9/28/76
Tyoe of Plant: Feldspar
Type of Discharge: Fugitive
Location of Discharge: Truck"loading
Height of Point of Discharge: 15 ft.
Descriotion of Background: Building wall
Description of Sky: N/A
Mind Direction: N/A
Color of Plume: N/A
Duration of Observation: 13 minutes
Summary of Data:
Ooacity,
Percent
Distance from Observer to Discharge Point:30
Height of Observation Point: ground level
Direction of Observer from Discharge Point;
Wind Velocity: N/A
Detached Plume: N/A
5
10
15
20
25
30
.35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min. Sec.
0
0
•Opacity,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Ona*
Mi n. Se
C-68
-------
Table 61
FACILITY G2
SUMMARY OF VISIBLE EMISSIONS
Date: 9/28/76
Tyoe of Plant: Feldspar
Type of Discharge: Fugitive
Location of Discharge: Railroad car loading
of Point of Discharge: 15 ft.
Distance from Observer to Discharge Point: 25 ft.
Descriotion of Background: Building wall Height of Observation Point: ground level
tocriotion of Sky: Cloudy
Wind Direction: M/A
Color of Plume: |\|/A
Duration of Observation: 32 minutes
Summary of Data:
Direction of Observer from Discharge Point: E
Wind Velocity: N/A
Detached Plums: N/A
Ooacity,
Percent
5
n
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
5
0
-
or
Opacity
Sec.
15
0
-
Opacity, Total Time Equal to or
Percent Greater Than Given Onacitv
Mi n . Sec .
55
60
65
70
75
80
85
90
05
100
C-69
-------
Table 63
FACILITY HI
SUMMARY OF VISIBLE EMISSIONS
Hate: 10/27 - 28/76
Tyoe of Plant: Gypsum
Type of Discharge: Fugitive (leaks)
Location of Discharge: Hammermill
Height of Point of Discharge: Leaks
Descriotion of Background: inside plant
Description of Sky: N/A
Wind Direction: N/A
Color of Plume: White
Duration of Observation: 298 minutes
Summary of Data:
Distance from Observer to Discharge Point: 25
Height of Observation Point: ground level
Direction of Observer from Discharge Point: $
Wind Velocity: N/A
Detached Plume: N/A
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
1
0
0
-
or
Opacity
Sec.
45
15
0
_
-Opacity,
Percent
55
60
65
70
75
80
85
90
95
100
Total Time Equal to or
Greater Than Given Onac
Min.
Sec
C-70
-------
pjin dumber
D,:U
Test. rime-minutes
ProducLion rate - TPH
Stack Effluent
Flow rate - ACR'I
flow rate DSCFM
Tempera turn - °F
Hater vapor - Vol.«
Visible Emissions at
Collector' Discharge -
Percent Opacity
Particul ate Emissions
P_robe_ and Filter Catch
gr/DSCF
cjr/ACF
Ib/hr
Ib/ton
Total Catch
gr/DSCF
gr/ACF
Ib/hr
Ib/ton
Table 64
FACILITY H2
Summary of "esr, 1 ts
1
10/27/76 10/27/76 10/28/76
88 88 88
4,548
3,542
145.4
4.6
0.071
0.055
2.16
0.073
0.057
2.53
4,364
3,486
147.0
1.8
See Table 64
0.063
0.050
1.87
0.064
0.051
2.40
4,306
3,423
145.3
2,6
0.066
0.053
1.94
0.068
0.054
2.65
Average
88
4,406
3,484
145.9
3.0
0.067
0.053
1.99
0.068
0.054
2.53
C-71
-------
TABLE 64
FACILITY H2
Summary of Visible Emissions
Date: 10/27/76
Type of Plant: Gypsum board manufacturer
Type of Discharge: Stack
Location of Discharge: Above plant roof
Distance from Observer to Discharge Point: ;
Height, of Observation Point: roof level
Height of Point of Discharge: 6' above roof Direction of Observer from Discharge Point:
225° (S.W.)
Description of Background: Sky
Description of Sky: Clear
Wind Direction: 0° (N)
Color of Plume: White
Duration of Observation: 87 Min
SUMMARY OF AVERAGE OPACITY
Wind Velocity: ~ 10 mph
Detached Plume: No
SUMMARY OF AVERAGE OPACITY
Opacity
Time
Time
Opacity
Set Number Start End
Sum
Average Set Number Start End Sum Average
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20 •• • '
1312;0a
1357:00
1403:00
1409:00
1415:00
1421:00
1427:00
1433:00
1439:00
1445:00
1451:00
1457:00
1503:00
1509:00
1515:00
1316:45
1402:45
1408:45
1414:45
1420:45
1426:45
1432:45
1438:45
1444:45
1450:45
i456:45
1502:45
1508:45
1514:45
1519:05
125
155
135
150
140
125
135
130
125
115
95
70
80
85
60
6.25
6.46
5.62
6.25
5.83
5.21
5.62
5.42
5.21
4.79
3*96
2.92
3.33
3.54
3.53
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Sketch Showing How Opacity Varied With Time:
c
OJ
o
i-
0)
o.
C-72
-------
I ABU: 64 (con't)
FACILITY H2
Summary of Visible Emissions
Date: 10/27/76
jype of Plant: Gypsum board manufacturer
Type of Discharge: Stack
Location of Discharge: Above plant roof
Distance from Observer to Discharge Point:25 ft
Height, of Observation Point: roof level
Height of Point of Discharge: 6' above roof Direction of Observer from Discharge Point:
225° (S.W.)
Description of Background: Sky
Description of Sky: Clear
Wind Direction: 45° (N.E.)
Color of Plume: White
Duration of Observation: 92 min.
SUMMARY OF AVERAGE OPACITY
Wind Velocity: ~ 10-15 mph
Detached Plume: No
SUMMARY OF AVERAGE OPACITY
Time
Set Number
1
2
3
4
5
6
7
8
'9
10
11
12
13
14
15
16
17
18
19
20
Start
0830:0.0
0836. ;QO
0842; 00
0848:00
0957:00
1003:00
1009:00
1015:00
1021:00
1027:00
1033:00
1039:00
1045:00
1051:00
1057:00
1103:00
1109:00
End
0835:45
0.841:45
0847:45
0849:00
1002:45
1008:45
1014:45
1020:45
1026:45
1032:45
1038:45
1044:45
1050:45
1056:45
1102:45
1108:45
1110:45
Opacity
Sum
45
65
70
5
125
60
80
85
75
70
85
95
90
90
70
55
25
Average
1.87
2.71
2.92
1.00
5.21
2.50
3.33
3.54
3.12
2.92
3.54
3.96
3.75
3.75
2.92
2.29
3.12
Time Opacity
Set Number Start End Sum Average
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Showing How Opacity Varied With Time:
U
i-
QJ
O.
C-73
-------
t 64 (con't)
FACILITY H2
Summary of Visible Emissions
Date: 10/28/76
Type of Plant: Gypsum board manufacturer
Type of Discharge: Stack
Location of Discharge: Above plant roof
Distance from Observer to Discharge Point:
Height, of Observation Point: roof level
Height of Point of Discharged' above roof Direction of Observer from Discharge Point:
225° (S.W.)
Description of Background: Sky
Description of Sky: Clear
Wind Direction: 180° (S)
Color of Plume: White
Duration of Observation: 87 min
SUMMARY OF AVERAGE OPACITY
Wind Velocity: ~ 10 mph
Detached Plume: No
SUMMARY OF AVERAGE OPACITY
Opacity
Opacity
Time
lime
Set Number Start End Sum Average Set Number Start End Sum Average
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
0830:00
0930:00
0936:00
0942:00
0948:00
0945:00
1000:00
1006:00
1012:00
1018:00
1024:00
1030:00
1036:00
1042:00
1048:00
0835:45
0935:45
0941:45
0947:45
0953:45
0959:45
1005:45
1011:45
1017:45
1023:45
1029:45
1035:45
1041:45
1047:45
1050:45
40
95
85
65
70
60
90
40
30
25
40
60
25
70
10
1.67
3.96
3.54
2.71
2.92
2.50
3.75
2.50
1.25
1.04
1.67
2.50
1.04
2.92
0.83
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Sketch Showing How Opacity Varied With Time:
ID
O
i-
-------
Table 65
FACILITY I
SUMMARY OF VISIBLE EMISSIONS
Date: 9/30/76
Tyoe of Plant: Mica
Type of Discharge: Fugitive
Location of Discharge: Bagging Operation
||ei
-------
Table 66
FACILITY Jl
SUMMARY OF VISIBLE EMISSIONS
Date: 10/20 - 21/76
Tyoe of Plant: Talc'
Type of Discharge: Fugitive (leaks)
Location of Discharge: Vertical mill
Height of Point of Discharge: In room
Qescriotion of Background: ceiling
Description of Sky: N/A
Wind Direction: N/A
Color of Plume: White
Duration of Observation: 90 minutes
Summary of Data:
Ooacity,
Percent
Distance from Observer to Discharge Point:10
Height of Observation Point: Floor
Direction of Observer from Discharge Point: W
Wind Velocity: ^/A
Detached Plume: |\|/A
5
10
15
20
25
30
35
40
45
50
Total Time Equal to or
Greater Than Given Opacity
Min."Sec.
0
0
•Opacity,
Percent
55
60
65
70
75
80
85
90
H5
100
Total Time Equal to or
Greater Than Given Onac
Mi n.
Sec
C-76
-------
Table 67
FACILITY Jl
SUMMARY OF VISIBLE EMISSIONS
late: 10/20/76
lyne of Plant: Talc
lyne of Discharge: Fugitive
location of Discharge: Primary crusher
Eight of Point of Discharge: in room
[escriotion of Background: wall
fcscrintion of Sky: |\|/A
find Direction: N/A
lolor of Plume: White
Gyration of Observation: gg minutes
luminary of Data
Ooacity,
Percent
10
15
20
25
30
35
40
45
50
Distance from Observer to Discharge Point: 5 ft
Height of Observation Point: Floor
Direction of Observer from Discharge Point:w
Wind Velocity: N/A
Detached Plume: N/A
Total Time Equal to or
Greater Than Given Opacity
Tlin.
20
8
1
0
Sec.
15
0
15
0
Opacity,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Onacitv
Mi n .
Sec .
C-77
-------
Table 68
FACILITY Jl
SUMMARY OF VISIBLE EMISSIONS
Date: 10/20 - 21/76
Tyoe of Plant: Talc'
Tyoe of Discharge: Fugitive
Location of Discharge: Secondary crusher
Height of Point of Discharge: in room
Oescriotion of Background: wall
Description of Sky: N/A
Wind Direction: N/A
Color of Plume: white
Duration of Observation: 150 minutes
Summary of Data:
Distance from Observer to Discharge Point: 5 ff
Height of Observation Point: floor
Direction of Observer from Discharge Point:5
Wind Velocity: N/A
Detached Plume: N/A
Ooacit.y,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
3
0
0
~
or
Opacity
Sec.
45
15
0
—
Opacity, Total Time Equal to or
Percent Greater Than Given Onacit
Mi n . Sec .
55
60
65
70
75
BO
85
90
05
100
C-78
-------
Table 69
FACILITY J1
SUMMARY OF VISIBLE EMISSIONS
Date: 10/19 - 21/76
Tyoe of Plant: Talc
Tyoe of Discharge: Fugitive
Location of Discharge: Bagger
Haifjht of Point of Discharge: In room
Descriotion of Background: wall
"tescrintion of Sky: N/A
Wind Direction: |\|//\
Color of Plume: White
Duration of Observation: 150 minutes
Summary of Data:
Distance from Observer to Discharge Point: 10 ft,
Height of Observation Point: floor
Direction of Observer from Discharge Point: W
Wind Velocity: N/A
Detached Plume: N/A
Ooacity,
Percent
5
n
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
12
5
3
2
2
2
1
1
1
1
or
Opacity
Sec.
45
15
0
15
0
0
30
30
15
15
Onacitv,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal
Greater Than Giv
Min.
0
0
0
0
0
_
to or
en Onacitv
Sec.
45
45
15
15
0
C-79
-------
Table 70
FACILITY Jl
SUMMARY OF VISIBLE EMISSIONS
Date: 10/19/76
Tyoe of Plant:
Type of Discharge: Fugitive
Location of Discharge: Pebble Mill No. 2
Height of Point of Discharge: in room
Descriotion of Background: Wall
Oescriotion of Sky: N/A
Wind Direction: N/A
Color of Plume: White
Duration of Observation: 90 minutes
Summary of Data:
Distance from Observer to Discharge Point:10 f
Height of Observation Point: floor
Direction of Observer from Discharge Point:w
Wind Velocity: |\|//\
Detached Plume: N/A
Ooacity,
Percent
5
10
15
20
25
30
35
40
45
50
Total Time Equal to
Greater Than Given
Min.
5
0
0
_
or
Opacity
Sec.
0
45
0
_,
•Opacity,
Percent
55
60
65
70
75
80
85
90
05
100
Total Time Equal to or
Greater Than Given Ooaci
Min.
Sec.
C-80
-------
Tost Mine-minutes
P rod uc Lion rate - TPM
Tcible 71
FACILITY
Sum:i;ory cf ''esu ! ts
10/20/76 10/20/76 10/21/76
120 120 120
120
Mo\/ rale - ACFM
['•"low rate - D5CFM
Temperature - °F
Hater vapor - Vol .«
Visible [.missions a I
Col lector Di'scharge -
•Percent Opacity
if,
P . i r t i c :_u 1 -••, t^__t._n 1 1 ssions
1 Prol)c 'and l''1'1 ':or Cdtch
(jr/ACF
Ib/hr
Ib/ton
(jr/DSCF
Ib/hr
Ib/Lon
21 ,100
20,200
80
0.3
21,300
20,200
83
0.3
21 ,300
19,500
82
1.0
21,200
20,000
82
0.5
See Table 72
0.047
0.045
8.17
0.068
0.065
11.8
0.067
0.061
11.2
0.061
0.057
10.4
0.065
0.062
11.2
0.071
0.067
12.2
0.068
0.062
11.3
0.068
0.064
11.6
C-81
-------
TABLE 72
FACILITY J2
Summary of Visible Emissions
Date: 10/21/76
Type of Plane: Talc
Type of Discharge: Stack
Location of Discharge: Baghouse Outlet
Height of Point of Discharge:30'
Description of Background: Hills and trees
Description of Sky: Overcast - rain
Wind Direction: 60° NE
Color of Plume: White
Duration of Observation: Approx. 2 hrs.
Distance from Observer to Discharge Point:
approx. 100'
Height, of Observation Point:
approx. 36'
Direction of Observer from Discharge Point:
160° SE
Wind Velocity: 8-12 mi/hr - Gust up to 20
Detached Plume: N/A
SUMMARY OF AVERAGE
Time
Set Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Start
08:00
08:06
08:12
08:18
08:24
08:30
08:36
08:42
08:48
08:54
09:00
09:06
09:12
09:18
09:24
09:30
09:36
09:42
09:48
09:54
End
08:06
08:12
08:18
08:24
08:30
08:36
08:42
08:48
08:54
09:00
09:06
09:12
09:18
09:24
09:30
09:36
09:42
09:48
09:54
10:00
OPACITY
Opacity
Sum
10
0
0
5
0
5
5
0
0
0
5
10
15
5
5
5
5
0
5
5
Average
0.4
0
0
0.2
0
0.2
0.2
0
0
0
0.2
0.4
0.6
0.2
0.2
0.2
0.2
0
0.2
0.2
SUMMARY OF AVERAGE OPACITY
Time Opacity
Set Number Start End Sum Average
21 10:00 10:05 0 0
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Sketch Showing How Opacity Varied With Time:
cu
OJ
CL
C-82
-------
TABLE 72 (con't)
FACILITY J2
Summary of Visible Emissions
Date: 10/20/76
Type of Riant: Talc
Type of Discharge: Stack
Location of Discharge: Baghouse Outlet
Height of Point of Discharge: 30'
Description of Background: Hills and trees
Description of Sky: Overcast - Rain
Wind Direction: 290° NW
Color of Plume: White
^Duration of Observation: 2:05 min.
SUMMARY OF AVERAGE OPACITY
Distance from Observer to Discharge Point: 100'
Height of Observation Point:approx. 36'
Direction of Observer from Discharge Point:
160° SE
Wind Velocity: 4-7 mi/hr
Detached Plume: N/A
SUMMARY OF AVERAGE OPACITY
Set Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
T
Start
12;54
13.:QO
13:06
13:12
13:18
13:24
13:30
13:36
13:42
13:48
13:54
14:00
14:06
14:12
14:18
14:24
14:30
14:36
14:42
14:48
line
End
13:00
13:06
13:12
13:18
13:24
13:30
13:36
13:42
13:48
13:54
14:00
14:06
14:12
14:18
14:24
14:30
14:36
14:42
14:48
14:54
Sum
0
0
0
5
5
10
5
5
15
15
5
0
5
0
5
0
5
5
0
0
Opacity
Average
0
0
0
0.2
0.2
0.4
0.2
0.2
0.6
0.6
0.2
0
0.2
0
0.2
0
0.2
0.2
0
0
Set Number
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Time Opacity
Start End Sum Average
14:54 14:59 0 0
Showing How Opacity Varied With Time:
C
0)
o
i.
01
Q.
C-83
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FABLE 72 (con't)
FACILITY J2
Summary of Visible Emissions
Date: 10/20/76
Type of Plant: Talc
Type of Discharge: Stack
Location of Discharge: Baghouse Outlet
Height of Point of Discharge: 30'
Description of Background: Hills and trees
Description of Sky: Overcast
Wind Direction: 290° NW
Color of Plume: White
Duration of Observation: 2:22 min.
SUMMARY OF AVERAGE OPACITY
Distance from Observer to Discharge Point:
approx. 100'
Height, of Observation Point:
approx. 36'
Direction of Observer from Discharge Point:
160° SE
Wind Velocity: 4-7 mi/hr
Detached Plume: N/A
SUMMARY OF AVERAGE OPACITY
Time
Set Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20 - *
Start
0.8:35
08:41
08:47
08:53
08:49
09:05
09:11
09:17
09:23
09:29
09:35
09:41
.09:47
09:53
09:59
10:05
10:11
10:17
10:23
10:29
End
08:41
08:47
08:53
08:59
09:05
09:11
09:17
09:23
09:29
09:35
09:41
09:47
09:53
09:59
10:05
10:11
10:17
10:23
10:29
10:35
Opacity
Sum
0
5
5
5
5
5
10
5
5
5
0
10
0
0
5
5
10
5
0
10
Average
0
0.2
0.2
0.2
0.2
0.2
0.4
0.2
0.2
0.2
0
0.4
0
0
0.2
0.2
0.4
0.2
0
0.4
Set Number
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Time Opacity
Start End Sum Average
10:35 10:41 5, 0.2
10:41 10:47 5 " 0.2
10:47 10:53 10 0.4
10:53 10:58 5 0.25
Sketch Showing How Opacity Varied With Time:
c
CD
O
5-
CL>
a.
C-84
-------
Test riiii',:--iii imites
Production rate: - TPH
Stack ill'fluent
Flow rate - ACFM
Flow rate DSCFM
Toii'.pcr.'! turo - °F
I'ldLor vajior - Vol .%
Visi')! c; .Lni issi ons at
Co 11 tit Opacity
Piift; icul -ito Fniissions
T.,blc 73
FACILITY K
Suiiiinary of ;'osi.; i ts
1 2 3
6/21/77 6/21/77 6/22/77
120 120 120
4,567 4,113 4,579
3,637 3,196 3,646
135.3 152.3 136.8
1.69 1.36 1.63
Average
120
4,420
3,493
141.5
1.56
See Table 74
Probe c-iiicl Filter Catch
c]r/[)5CF
•cjr/ACF
Ib/hr
Ib/ton
Totrtl Cajxh
gr/nSCF
/ i y» / A ' P [7
( j r / / \u t
Ib/hr
Ib/ton
0.024 0.027 0.041 0,031
0.020 0.022 0.034 0.025
0.75 0.75 1.29 0.93
-
C-85
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FACILITY K
Summary of Visible Emissions
Date: 6/20 - 6/21/71
Type of Plant: Talc
Type of Discharge: Stack
Location of Discharge: Pebble mill
Height of Point of Discharge:40 ft.
Description of Background:Equipment and Mountain
Description of Sky: Clear
Wind Direction: North Wind Velocity: 5 mph
Color of Plume: White Detached Plume: N/A
Duration of Observation:
SUMMARY OF AVERAGE OPACITY SUMMARY OF AVERAGE OPACITY
Distance from Observer to Discharge Point: 12'"
Height, of Observation Point:25 ft.
Direction of Observer from Discharge Point: W
lime
Opacity
lime
Opacity
Set Number Start End
Sum
Average Set Number Start End Sum Average
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
1314
1320
1326
1332
1338
1344
1350
1356
1402
1408
1417
1423
1429
1435
1441
1447
1453
1459
1505
1511
1320
1326
1332
1338
1344
1350
1356
1402
1408
1414
1423
1429
1435
1441
1447
1453
1459
1505
1511
1517
80
10
5
10
10
0
5
0
5
5
5
5
5
10
5
0
0
5
0
10
3.33
0.42
0.21
0.42
0.42
0.0
0.21
0.0
0.21
0.21
0.21
0.21
0.21
0.42
0.21
0.0
0.0
0.21
0.0
0.42
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
802
808
814
820
826
832
838
844
850
856
903
909
915
921
927
933
939
945
951
957
808
814
820
826
832
838
844
850
856
902
909
915
921
927
933
939
945
951
957
1003
10
5 '
5
30
0
0
40
75
50
65
35
20
55
25
55
55
30
55
70
40
0.42
0.21
0.21
1.25
0.0
0.0
1.67
3.13
2.08
2.32
1.46
0.83
2.29
1.04
2.29
2.29
1.24
2.29
2.92
1.67
Sketch Showing How Opacity Varied With Time:
QJ
o
0)
a.
C-86
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TABLE 74 (con't)
FACILITY K
Summary of Visible Emissions
Date: 6/20 - 6/21/71
Type of Plant: Talc
Type of Discharge: Stack
Location of Discharge: Pebble Mill
Height of Point of Discharge: 40 ft.
Description of Background: Equipment and Mountain
Description of Sky: Clear
Kind Direction: North Wind Velocity: 5 mph
Color of Plume: White Detached Plume: N/A
Oration of Observation:
SUMMARY OF AVERAGE OPACITY SUMMARY OF AVERAGE OPACITY
Distance from Observer to Discharge Point:125 ft
Height, of Observation Point: 25 ft.
Direction of Observer from Discharge Point: W
Time
Opacity
nme
Opacity
iet Number Start End Sum Average Set Number Start
End
Sum Average
1
2
3
4
5
6
7
8
'9
10
11
12
13
14
15
16
17
18
19
20
1004
1208
1214
1220
1226
1232
1238
1244
1250
1256
1302
1313
1319
1325
1331
1337
1343
1349
1355
1401
1009
1214
1220
1226
1232
1238
1244
1250
1256
1302
1308
1319
1325
1331
1337
1343
1349
1355
1401
1407
30
105
no
85
90
125
85
105
95
25
65
95
105
40
30
60
55
35
5
75
1.25
4.38
4.58
3.54
3.75
5.21
3.54
4.38
3.96
1.32
2.95
3.96
4.38
1.67
1.30
2.61
2.29
1.94
0.36
3.13
21 1407 1413 125 5.21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
letch Showing How Opacity Varied With Time:
c
01
u
i.
01
n.
C-87
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TABLE 75. FACILITY LI
#8 Raymond Impact hill Baghouse Inlet
Summary 0^ Test Resul_t_s
Te s t Da t
-------
TABLE 76. FACILITY LI
#8 Raymond Impact Mil! Baghouse Exhaust
Summary of Test Results
Test Data
Test Number
Test Date
Test Time
12-6-78
1355-15*40
12-6-78
1655-18^0
12-6-78
19^-2130
Gas F1ow
Standard Cubic Feet/minute, dry
Actual Cubic Feet/minute, wet
Partlcuiates
Nozzle and Front Half Filter Holder
Catch Fraction, g
Filter Catch Fraction, g
Total Particulates,g
Part leu late Emissions
Grains/dry standard cubic foot
Pounds/hour
Baghouse Particulate Removal
Efficiency.percent
Visible Emissions3
5 percent opacity, minutes observed
0 percent opacity, minutes observed
Unobserved readings, minuted observwc.'
1*4,790.
17,690.
0.020
0.0
90.0
0.0
U.650.
17,960.
15,080,
18,060,
0.0381
0.0^7
0.0828
0.0228
0.0309
0.0537
0.0258
0.01460
0.0/18
0.012
99-72
0.016
2.01
Based on Total Particulates captured by train.
Standard Conditions = 68 F and 29-92 inches mercury
3
Opacity results !!• H are in minutes of (.he observed reading during the test perioc
C-89
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TABLE 77. FACILITY 12
Roller Mills Beghouse Inlet
Summary of Tes t Results
Test Data
Test Number '
Test Date 12-6-78
Test Time 1053-12^0
Standard Cubic Feet/minute, dry 6,960.
Actual Cubic Feet/minute, vvet 8,550.
Part i cul ates
Nozzle, Probe and Front Half Filter Holder 1.1*983
Catch Fraction, g
Filter Catch Fraction , g 3-M16
Total Particulates, g ^.9399
Particulate Emissions
Grains/dry standard cubic foot 1-76
Pounds/hour 105-
Based on Total Particulates captured by train.
Standard Conditions = 68 F and 29-92 Inches mercury.
Test conducted concurrently with Run 3, Roller Mills Baghouse Exhaust Test.
C-90
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TABLE 78. FACILITY 12
Roller Mills Baghouse Exhaust
Summary of Test Results
Test Data
Test Number 1 2 3
Test Date 12-5-78 12-5-78 12-6-78
Test Time 0953-1203 1357-1605 1030-1252
Gas Flow
Standard Cubic Feet/Minute,dry 8,120. 8,150. 8,560.
Actual Cubic Feet/minute, wet 9,780. 9,830. IOJ40.
Part i cul ates
Nozzle and Front Half Filter Holder
Catch Fraction, 9 0.0335 0.0152 0.0241
Filter Catch Fraction, 9 0.0107 0.0075 0.0029
Total Particulates, 9 0.0442 0.0227 0.0270
Particulate Emissions
Grains/dry standard cubic foot2 0.010 0.005 0.007
Pounds/hour 0.73 0.38 0.48
Baghouse Particulate Removal Efficiency,
percent - - 99-54
Visible Emissions
>_ 10 percent opacity, minutes observed 0.0
5 percent opacity, minutes observed 112.75
0 percent opacity, minutes observed 3- 120.0 120.0
Unobservable reading, minutes observed 4.25
Based on Total Partlculates captured by train.
Standard Conditions « 68 F and 29.92 inches mere ury
Opacity results listed are in minutes of the observed reading during the 120
minute test period.
C-91
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TABLE 79
FACILITY N
Summary of Results of Fugitive Emission Tests performed
on three separate rail car loadings
Observation
area
A
B
C
A
B
C
A
B
C
Accumulated
observation
period
(min:sec)
144:32
144:32
144:32
99:45
99:45
99:45
154:20
154:20
154:20
Accumulated
emission
time
(mi n: sec)
Test #1
22:42
17:30
0:00
Test #2
18:50
2:06
0.00
Test #3
63:42
0:20
9:21
% Emission
(AOP/AET x 100)
15.7
12,1
0
x = 9.3
18.9
2.1
0
x = 7.0
41.3
0.2
6.1
x = 15.9
1. Designation of observation positions (Figure 1)
A. Loading hose
B. West end of shed
C. East end of shed
C-92
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Table 80 represents visible emission data given in this Appendix, on a
basis of percent of total time of recorded visible emissions (e.g., in a Method
22 format). These observations were executed for fugitive emissions. The use
of Method 22, as it applies to the proposed standard for non-metallic mineral
processing plants would be applicable to fugitive sources of dust. This test
would also be employed to check the effectiveness of a capture or wet suppression
system, if used, at any process facility. A description of each of the process
facilities listed in Table 80 is given at the beginning of this Appendix.
Data for 53 observation periods of visible emissions readings covering 43
process facilities at nine non-metallic processing plants is given in Table 80.
All facilities observed were fugitive emission discharges from uncontrolled,
hooded or wet suppression controlled facilities. Three process facilities
exceeded the proposed 10 percent of total time of visible emissions standard
set for them. Neither of the two rail car loading process facilities exceeded
the proposed 15 percent of total time of visible emissions standard set for this
particular process facility.
C-93
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TABLE 80. SUMMARY OF VISIBLE EMISSIONS MEASUREMENTS FROM FUGITIVE SOURCES AT
NON-METALLIC MINERALS PLANTS
o
I
UD
Date of Accumulated
Plant/Rock type processed ? ° Process facility observation time
test (minutes)
A
B
D
F
Crushed limestone 7/9/75 Baghouse discharge to conveyor
Primary impact crusher discharge
Conveyor transfer point
Crushed limestone 7/1/75 Scalping screen
Surge bin
Secondary cone crusher No. 1
Secondary cone crusher No. 2
Secondary cone crusher No. 3
Hammer mil 1
3-deck finishing screen (L)
3-deck finishing screen (R)
6/30/75 Two 3-deck finishing screens
Crushed stone 7/8/75 No. 1 tertiary gyrasphere
cone crusher
No. 2 tertiary gyrasphere
cone crusher
Secondary standard cone crusher
Scalping screen
Secondary (2-deck) sizing screen
Secondary (3-deck) sizing screen
Trapro.ck 8/26/76 Two tertiary crushers
Four processing screens
Conveyor transfer points
240
240
166
287
287
231
231
231
287
107
107
120
170
170
170
210
210
210
65
180
179
Accumulated
emission time
(minutes)
0
4
3
45
3
23
0
0
0
4
0
86
0
0
0
0
0
0
0
0
0
Percent of time
with visible
emissions
0
1
2
15
1
10
0
0
0
4
0
72
0
0
0
0
0
0
0
0
0
(continued)
-------
TABLE 80 (continued)
o
I
Date of Accumulated
Plant/Rock type processed Process facility observation time
test (minutes)
G Feldspar
H Gypsum
I Mica
J Talc
N Kaolin
9/27/76 Conveyor transfer point No. 1
Conveyor transfer point No. 2
Primary crusher
Secondary crusher
Conveyor transfer point No. 4
Ball mill (feed end)
Ball mill (discharge end)
Indoor transfer point No. 1
Indoor transfer point No. 2
Indoor bucket elevator
Truck loading
Rail car loading
10/27/76 Hammer mill
9/30/76 Bagging operation
10/21/76 Vertical mill
Primary crusher
Secondary crusher
Bagger
Pebble mill
12/7/78 Rail car loading
Test 1
Test 2
Test 3
80
87
60
60
84
60
60
60
60
60
13
32
298
60
90
90
150
150
90
144
99
154
Accumulated
emission time
(minutes)
0
0
1
0
0
0
0
0
0
0
0
5
2
0
0
20
4
13
6
17
2
9
Percent of time
with visible
emissions
0
0
2
0
0
0
0
0
0
0
0
15
1
0
0
22
3
9
7
12
2
6
-------
APPENDIX D
EMISSION MEASUREMENT AND CONTINUOUS MONITORING
D.I EMISSION MEASUREMENT METHODS
For participate matter and visible emissions measurements from stacks,
EPA relies primarily upon Methods 5 and 9, which have been established as
reference methods. In addition, a new reference method, Method 22, is being
proposed to determine compliance with the fugitive emissions standard. The
proposed method requires that observations of visible emissions be made for a
minimum of 1 hour. It determines the amount of time that any visible
emissions occur during the observation period, but not the opacity of the
emissions. The proposed method specifies that uncombined water vapor is not
considered visible emissions for determining compliance with the standard.
An observer performs the visible observations over a minimum observation
period of 1 hour, noting the total number of minutes in the total observation
period that visible emissions were observed. Dividing the amount of time that
visible emissions were observed by the total observation time yields the
percentage of time of visible emissions. The emission data from the non-
metallic industry may be obtained using these reference methods as prescribed
in the Federal Register. In addition, as the particulate concentrations are
expected to be independent of temperature for this industry, Method 17 (in-
stack filtration) is an acceptable particulate sampling method.
D-l
-------
The one serious problem encountered during the testing of stacks in the
non-metallic minerals industry was the low concentration levels of particulate.
Some emissions tests resulted in particulate catches of less than 10 mg
corresponding to 0.0005 gr/dscf. An EPA laboratory study showed that because
of positive biases from the "clean-up" blank, results from tests where low
concentration levels are encountered are biased toward the high side. This
bias was no more than a factor of two for particulate catches down to 8 mg.
Data from an EPA report, "Additional Studies on Obtaining Replicate
Particulate Samples From Stationary Sources," by William J. Mitchell, indicate
that particulate catches of about 50 mg are adequate to insure an error of no
more than 10 percent. Lower levels were not studied. Based on theoretical
calculations, particulate weights as small as 12 mg were estimated to be
sufficient to insure an error no greater than 10 percent.
D.2 MONITORING SYSTEMS AND DEVICES
The effluent streams from the non-metallic industry sources are at
essentially ambient conditions. The visible emissions monitoring instruments
found adequate for power plants would also be applicable for this industry.
These systems are covered by EPA performance standards contained in Appendix B
of 40 CFR Part 60.
Equipment and installation costs are estimated to be $18,000 to $20,000
and annual operating costs, including data recording and reduction, are
estimated at $8,000 to $9,000.
D.3 PERFORMANCE TEST METHODS
Either Method 5 or 17 for particulate matter is recommended as the per-
formance test method. Due to low concentrations sometimes encountered, a
minimum sample volume must be established to insure adequate amounts of
D-2
-------
particulate matter are collected to minimize recovery errors. This participate
catch amount is preferably 50 mg, but should be at least 25 mg. It is also
recommended that sampling trains with higher sampling rates, which are
allowed by Method 5 and are commercially available, be used to reduce sampling
time and costs.
Sampling costs for a test consisting of three particulate runs, the
number normally specified by performance test regulations, is estimated to
be about $5,000 to $7,000. This estimate is based on sampling site modifi-
cations and testing being conducted by contractors. If in-plant personnel
are used to conduct the test, the costs will be somewhat less.
Since the outlet gas streams from control devices used in this industry
are generally well contained, no special sampling problems are anticipated.
D-3
-------
APPENDIX E
ENFORCEMENT ASPECTS
The recommended standards of performance will limit the emission of
participate matter from non-metallic minerals processing plants. These
standards include both concentration and visible emission limitations. The
control systems which could be installed to comply with these standards
include dry collection systems, wet dust suppression systems or a combi-
nation of the two. Aspects of enforcing the recommended standards of per-
formance are discussed below.
E.I PROCESS OPERATION
Factors affecting the level of uncontrolled particulate emissions from
non-metallic minerals processing plants include the type and amount of min-
eral processed, its moisture content, and its size distribution. For
crushers and grinders, the reduction mechanism used and the amount of size
reduction performed also affect uncontrolled emissions. In addition, sub-
stantial operating changes, which are within the design limits of the plant,
may be required to meet changing product demands. Consequently, when a new
plant is constructed or an existing one modified, it is important
that a record be made of (1) the intended purpose for which it was
installed, (2) any anticipated variations in the characteristics of the ma-
terials to be handled and the products to be produced, and (3) maximum design
capacity and anticipated normal operating capacity. The control system should
E-l
-------
be designed to assure that standards of performance are acheivable for any
and all anticipated process variations and meteorological conditions.
Process parameters which should be monitored to ensure that facilities
are operated normally during enforcement tests include the weight rate and
the moisture content of the feed during various process operations. In addi-
tion, some indication of the size distribution of both the feed and product
of these operations should be obtained,. Due to the nature of the industry,
the process weight rate through a specific piece of process equipment may be
impossible to determine. In these cases, the process weight rate should be
monitored at the nearest determinable upstream location which, in some in-
stances, may be the feed to the primary crusher. An analysis of the moisture
content of the material processed is very important to ensure that dust con-
trol at the time of the test is effected by the control system and not the
result of unusually high moisture levels which are not normally maintained.
Where the addition of moisture is part of the control system (e.g., wet dust
suppression) a record should be made of the percent moisture required to effec-
tively control emissions.
E.2 DETERMINATION OF COMPLIANCE WITH THE CONCENTRATION STANDARD
Control devices used to control particulate emissions from non-metallic
minerals processing plants exhaust their effluents to the atmosphere either
through a stack or directly through a blower. The methods specified in
40 CFR 60 (methods 1, 2, 3, 4, and 5) provide specific guidelines for the
measurement of particulate emissions from a stack. Unlike existing pieces of
process equipment which sometimes require deviation from optimum sampling pro-
cedures due to physical limitations in the emission discharge configuration,
new pieces of equipment can and should be designed to assure that optimum
E-2
-------
conditions exist. For example, the optimum sampling location is a distance
equal to 8 or more duct diameters downstream and 2 or more upstream from any
constriction, expansion or other element that might disturb the flow pattern
of the gas stream. Although the reference methods allow deviation from this
optimum criteria, new pieces of equipment should be installed to ensure that
the results from emission measurements are as accurate and precise as possible
Furthermore, utility services and sample access points can also be incor-
porated into the design of new equipment to facilitate sampling.
Sampling problems encountered, where emissions are exhausted directly
to the atmosphere through a blower, can be overcome by the use of stack
extensions. These extensions may be either temporary or permanent and should
be designed to conform as nearly as possible to optimum sampling criteria.
As noted above, a control system may serve one or several process oper-
ations. The recommended standard provides that in the latter case, where
the emissions from several process operations are aspirated to a single con-
trol device (e.g., baghouse), a performance test of the single control device
is sufficient to show compliance for all the process operations serviced.
E.3 DETERMINATION OF COMPLIANCE WITH VISIBLE EMISSION STANDARDS
Due to the time and expense of performing quantitative emission measure-
ments via Method 5 or 17, they do not provide an economically feasible means
of ensuring, on a day-to-day basis, that emissions are within prescribed
allowable limits. Furthermore, in cases where emissions are not amenable to
measurement (such as emissions from non-metallic minerals facilities con-
trolled by wet dust suppression techniques) visible emission standards offer
the only viable alternative to mass standards. They require only a trained
observer and can usually be performed with minimal preparation and no prior
E-3
-------
notice to the owner. When promulgated with particulate standards they help
assure that emission control devices continue to be properly maintained and
operated. Visible emission standards which limit emissions that escape cap-
ture at hoods and enclosures are necessary to ensure that local capture sys-
tems are properly designed and also maintained. Therefore, visible emission
standards are established as independent, enforceable standards. All visible
emission observations should be made in accordance with the procedures es-
tablished in EPA Method 9 for stack emissions and Method 22 for capture
systems.
The visible emission observations made to ensure that local capture sys-
tems are properly designed and maintained are made from outside the building en^
closing the affected facility. If there are pieces of process equipment in the
same building which are not covered by the NSPS and visible emissions are
observed from the building, then the inspector should check the process equip-
ment inside the building to determine if the emissions are being generated by
an affected process operation.
E.4 EMISSION MONITORING REQUIREMENTS
The recommended standards do not require the installation of continuous
monitoring systems to monitor the opacity of the effluent gas streams dis-
charged into the atmosphere from control devices. As discussed in Chapter 8,
the estimated costs of procurement, installation and maintenance of continuous
monitors is considered excessive compared to the investment costs of the con-
trol system, regardless of benefits in enforcing the standard. It is recom-
mended, however, that hood face (capture) velocities and duct conveying ve-
locities be determined and recorded during compliance tests and that oper-
ators be required to periodically check present values against those recorded.
E-4
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