[Federal Register Volume 61, Number 250 (Friday, December 27, 1996)]
[Proposed Rules]
[Pages 68430-68451]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-31706]



[[Page 68429]]

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Part V





Environmental Protection Agecny





_______________________________________________________________________



40 CFR Part 63



National Emission Standards for Hazardous Air Pollutants Phosphoric 
Acid Manufacturing and Phosphate Fertilizers Production; Proposed Rule

  Federal Register / Vol. 61, No. 250 / Friday, December 27, 1996 / 
Proposed Rules  

[[Page 68430]]



ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 63

[IL-64-2-5807; FRL-5656-4]
RIN 2060-AE40 and 2060-AE44


National Emission Standard for Hazardous Air Pollutants 
Phosphoric Acid Manufacturing and Phosphate Fertilizers Production

AGENCY: Environmental Protection Agency (Agency).

ACTION: Proposed rule and notice of public hearing.

-----------------------------------------------------------------------

SUMMARY: This action proposes national emission standards for hazardous 
air pollutants (NESHAP) for new and existing major sources in 
phosphoric acid manufacturing and phosphate fertilizers production 
plants. Hazardous air pollutants (HAPs) emitted by the facilities 
covered by this proposed rule include hydrogen fluoride (HF); arsenic, 
beryllium, cadmium, chromium, manganese, mercury, and nickel (HAP 
metals); and methyl isobutyl ketone (MIBK) emissions. Human exposure to 
the HAP constituents in these emissions may be associated with adverse 
carcinogenic, respiratory, nervous system, dermal, developmental, and/
or reproductive health effects. Implementation of the proposed 
requirements would achieve an emission reduction of HF estimated at 315 
megagrams per year (Mg/yr) (345 tons per year [tpy]). The standards 
would reduce 940 Mg/yr (1035 tpy)of total fluorides and particulate 
matter containing heavy metals which are regulated pollutants under the 
Clean Air Act as amended (the Act).
    The standards are proposed under the authority of section 112(d) of 
the Act and are based on the Administrator's determination that 
phosphoric acid manufacturing and phosphate fertilizers production 
plants may reasonably be anticipated to emit several of the 189 HAPs 
listed in section 112(b) of the Act from the various process operations 
found within the industry. The proposed NESHAP would provide protection 
to the public by requiring all phosphoric acid manufacturing and 
phosphate fertilizers plants that are major sources to meet emission 
standards reflecting the application of the maximum achievable control 
technology (MACT).

DATES: Comments. Comments on the proposed standards must be received on 
or before February 25, 1997 at the address noted below.
    Public hearing. If anyone contacts the Agency requesting to speak 
at a public hearing, the hearing will be held on February 10, 1997 
beginning at 9 a.m. Persons wishing to present oral testimony must 
contact the Agency by January 21, 1997.

ADDRESSES: Comments. Interested parties may submit written comments (in 
duplicate if possible) to Public Docket No. A-94-02 at the following 
address: U.S. Environmental Protection Agency, Air and Radiation Docket 
and Information Center (formerly known as the Air Docket) (6102), 401 M 
Street, S.W., Washington, DC 20460. The Agency requests that a separate 
copy also be sent to the contact person listed below. The docket is 
located at the above address in Room M-1500, Waterside Mall (ground 
floor), and may be inspected from 8 a.m. to 4 p.m., Monday through 
Friday. The docket is an organized and complete file of all the 
information submitted to or otherwise considered by Agency in the 
development of this proposed rulemaking. For additional information on 
the Docket and electronic availability see Supplementary Information.
    Public Hearing. If anyone contacts the Agency requesting to speak 
at a public hearing, the hearing will be held at the Agency's Office of 
Administration Auditorium, Research Triangle Park, North Carolina. If a 
public hearing is requested and held, EPA will ask clarifying questions 
during the oral presentation but will not respond to the presentations 
or comments. Written statements and supporting information will be 
considered with equivalent weight as any oral statement and supporting 
information subsequently presented at a public hearing, if held. 
Persons wishing to present oral testimony or to inquire as to whether 
or not a hearing is to be held should notify Ms. Cathy Coats, Minerals 
and Inorganic Chemicals Group (MD-13), U.S. Environmental Protection 
Agency, Research Triangle Park, North Carolina 27711, telephone number 
(919) 541-5422.

FOR FURTHER INFORMATION CONTACT: For information concerning specific 
aspects of this proposal, contact Mr. David Painter [telephone number 
(919) 541-5515], Minerals and Inorganic Chemicals Group, Emission 
Standards Division (MD-13), U.S. Environmental Protection Agency, 
Research Triangle Park, North Carolina 27711.

SUPPLEMENTARY INFORMATION:

    Regulated Entities. Today's proposed rulemaking would apply to 
process components at new and existing phosphoric acid manufacturing 
and phosphate fertilizers production plants. Examples of those process 
components are listed in the following table:

------------------------------------------------------------------------
              Source category                         Examples          
------------------------------------------------------------------------
Phosphoric acid manufacturing.............  Wet Process Phosphoric Acid 
                                             Plant, Superphosphoric Acid
                                             Plant, Phosphate Rock      
                                             Dryer, Phosphate Rock      
                                             Calciner, Purified         
                                             Phosphoric Acid Plant.     
Phosphate fertilizers production..........  Diammonium and/or           
                                             Monoammonium Phosphate     
                                             Plant, Granular Triple     
                                             Superphosphate Plant,      
                                             Granular Triple            
                                             Superphosphate Storage     
                                             Building.                  
------------------------------------------------------------------------

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be regulated by the 
proposed regulations. This table lists the types of entities that the 
Agency is now aware could be potentially regulated. To determine 
whether your facility could be regulated by the proposed regulations, 
you should carefully examine the applicability criteria in the proposed 
rules. If you have questions regarding the applicability of this action 
to a particular entity, consult the person listed in the preceding FOR 
FURTHER INFORMATION CONTACT section.
    The principal purposes of the docket are: (1) to allow interested 
parties to readily identify and locate documents so that they can 
intelligently and effectively participate in the rulemaking process, 
and (2) to serve as the record in case of judicial review. The docket 
index, technical support information, the economic profile of the 
industry (item II-A-27) and other materials related to this rulemaking 
are available for review in the docket center or copies may be mailed 
on request from the Air and Radiation Docket and Information Center by 
calling (202) 260-7548 or 7549. The FAX number for the Center is (202) 
260-4000. A reasonable fee may be charged for copying docket materials.
    In addition to being available in the docket, an electronic copy of 
today's document which includes the proposed regulatory text is 
available on the Technology Transfer Network (TTN), one of Agency's 
electronic bulletin boards. The TTN provides information and technology 
exchange in various areas of air pollution control. The service is 
free, except for the cost of a phone call. Dial (919) 541-5742 for up

[[Page 68431]]

to a 14,400 bps modem. If more information on the TTN is needed, call 
the TTN HELP line at (919) 541-5384.
    The information in this preamble is organized as shown below.

I. Statutory Authority
II. Introduction
    A. Background
    B. NESHAP for Source Categories
    C. Health Effects of Pollutants
    D. Phosphoric Acid Manufacturing and Phosphate Fertilizers 
Production Industry Profile
III. Summary of Proposed Standards
    A. Applicability
    B. Emission Limits and Requirements
    C. Performance Test and Compliance Provisions
    D. Monitoring Requirements
    E. Notification, Recordkeeping, and Reporting Requirements
IV. Selection of Proposed Standards
    A. Selection of Source Categories
    B. Selection of Emission Sources and Pollutants
    C. Selection of Proposed Standards for Existing and New Sources
    1. Background
    2. Emissions Limits--General
    3. Emission Limits for Classes of Sources
    D. Selection of Test Methods
    E. Selection of Monitoring Requirements
    F. Selection of Notification, Reporting, and Recordkeeping 
Requirements
    G. Solicitation of Comments
V. Impacts of Proposed Standards
    A. Applicability
    B. Air Quality Impacts
    C. Water Impacts
    D. Solid Waste Impacts
    E. Energy Impacts
    F. Nonair Environmental and Health Impacts
    G. Cost Impacts
    H. Economic Impacts
VI. Administrative Requirements
    A. Docket
    B. Public Hearing
    C. Executive Order 12866
    D. Enhancing the Intergovernmental Partnership Under Executive 
Order 12875
    E. Unfunded Mandates Reform Act
    F. Regulatory Flexibility Act
    G. Paperwork Reduction Act
    H. Clean Air Act
    I. Pollution Prevention Act

I. Statutory Authority

    The statutory authority for this proposal is provided by sections 
101, 112, 114, 116, and 301 of the Clean Air Act, as amended (42 U.S.C. 
7401, 7412, 7414, 7416, and 7601).

II. Introduction

A. Background

    The EPA estimates that up to 550 Mg/yr (605 tpy) of HF, the 
predominate HAP, and other HAPs are emitted from sources at phosphoric 
acid manufacturing and phosphate fertilizers production plants at the 
current level of control. Implementing MACT-level controls is expected 
to reduce these HAP emissions from regulated sources by about 315 Mg/yr 
(345 tpy) nationwide. Plants affected by the standards could achieve 
these reductions by upgrading or installing wet scrubbing systems.
    The overall effect would be to raise the control performance of 
plants in the industry to the level achieved by the best performing 
plants. In addition to the health and environmental benefits associated 
with HAP emission reductions, benefits of this action include a 
decrease in site-specific levels of nonHAP pollutants and lowered 
occupational exposure levels for employees.
    The nationwide capital and annualized costs of the proposed NESHAP, 
including emission controls and associated monitoring equipment, are 
estimated at $1.4 million and $862,000/yr, respectively. The economic 
impacts are predicted to increase prices in all products less than 
three fourths of a percent. At least one company in the industry is a 
small entity which would be subject to the proposed standards. The 
economic impact of the proposed NESHAP on this company is estimated to 
be low and would not be significant. No production line or plant 
closures are expected.
    The Agency has proposed controls at the MACT-floor level and 
tailored the requirements to allow less-costly testing and monitoring 
by using surrogates for HAP emissions.
    A detailed description of industry processes and emissions data 
used to support the standards is presented in the draft ``Technical 
Support Document for Phosphoric Acid Manufacturing and Phosphate 
Fertilizers Production NESHAP'' which, along with additional supporting 
information is included in a memorandum in air docket A-94-02, as item 
II-B-20. This memorandum is referred to as the TSD in the following 
discussions.

B. NESHAP for Source Categories

    Section 112 of the Act requires that EPA promulgate regulations for 
the control of HAP emissions from both new and existing major sources. 
The statute requires the regulations to reflect the maximum degree of 
reduction in emissions of HAPs that is achievable taking into 
consideration the cost of achieving the emission reduction, any nonair 
quality health and environmental reduction, and energy requirements. 
This level of control is commonly referred to as the maximum achievable 
control technology (MACT).
    The control of HAPs is achieved through the promulgation of 
technology-based emission standards under sections 112(d) and 112(f) 
and work practice standards under 112(h) for categories of sources that 
emit HAPs. Emission reductions may be accomplished through the 
application of measures, processes, methods, systems, or techniques 
including, but not limited to: (1) Reducing the volume of, or 
eliminating emissions of, such pollutants through process changes, 
substitution of materials, or other modifications; (2) enclosing 
systems or processes to eliminate emissions; (3) collecting, capturing, 
or treating such pollutants when released from a process, stack, 
storage or fugitive emissions point; (4) design, equipment, work 
practice, or operational standards (including requirements for operator 
training or certification) as provided in subsection (h); or (5) a 
combination of the above. [See section 112(d)(2).] The EPA may 
promulgate more stringent regulations at a later date to address 
residual risk that remains after the imposition of controls. [See 
section 112(f)(2).]

C. Health Effects of Pollutants

    The Act was created, in part, ``to protect and enhance the quality 
of the Nation's air resources so as to promote the public health and 
welfare and the productive capacity of its population'' (CAA, section 
101(b)(1)). Title III of the Act establishes a control technology-based 
program to reduce stationary source emissions of HAPs. The goal of 
section 112(d) is to apply such control technology to reduce emissions 
and thereby reduce the hazard of HAPs emitted from stationary sources.
    This proposed rule is technology-based (i.e., based on MACT). The 
Act's strategy avoids dependence on a risk-based approach which would 
be limited by incomplete information on what HAPs are emitted, what 
level of emissions is occurring, what health and safety benchmarks are 
available to assess risk, what health effects may be caused by certain 
pollutants, and how best to model these effects, among other things. 
Because of these issues, a detailed quantitative risk assessment of 
potential effects from HAPs emitted from phosphoric acid manufacturing 
and phosphate fertilizer production plants is not included in this 
rulemaking.
    The EPA does recognize that the degree of adverse effects to health 
can range from mild to severe. The extent and degree to which the 
health effects may be experienced is dependent upon (1) the ambient 
concentrations observed

[[Page 68432]]

in the area, (2) duration of exposures, and (3) characteristics of 
exposed individuals (e.g., genetics, age, pre-existing health 
conditions, and lifestyle) which vary significantly with the 
population. Some of these factors are also influenced by source-
specific characteristics (e.g., emission rates and local meteorological 
conditions) as well as pollutant-specific characteristics.
    Available emission data, collected during development of this 
proposed NESHAP, show that HF, a number of HAP metals, and MIBK are the 
most significant HAPs emitted from phosphoric acid manufacturing and 
phosphate fertilizer production plants. These pollutants have the 
potential to be reduced by implementation of the proposed emission 
limits. Following is a summary of the potential health effects 
associated with exposures, at some level, to emitted pollutants that 
would be reduced by the standard.
    Short-term inhalation exposure to gaseous HF and related fluoride 
compounds can cause severe respiratory damage in humans, including 
severe irritation and pulmonary edema. Long-term inhalation exposures 
to low levels of HF by humans has been reported to result in irritation 
and congestion of the nose, throat, and bronchi while damage to liver, 
kidney, and lungs has been observed in animals. Long-term inhalation 
exposure, at levels of HF well above the ambient concentrations being 
observed at phosphate fertilizers complexes can result in skeletal 
fluorosis (i.e., an accumulation of fluoride in the bones). There is 
generally a lack of information on human health effects associated with 
exposures to hydrogen fluoride at current ambient air concentrations 
near phosphate fertilizers complexes. Occupational studies have not 
specifically implicated inhaled fluoride as a cause of cancer and the 
Agency has not classified HF with respect to potential carcinogenicity.
    Almost all metals appearing on the section 112(b) list of HAPs are 
emitted from phosphoric acid manufacturing and phosphate fertilizers 
production facilities. The most important of the nonvolatile metals 
that would be reduced by the standard are arsenic, beryllium, cadmium, 
chromium, nickel, and manganese compounds. The major target of toxicity 
for these metals via inhalation tends to be the respiratory tract, with 
the exception of manganese, for which the central nervous system is the 
primary target. These metals can cause a range of effects including 
mucous membrane irritation (e.g., bronchitis, decreased lung function), 
gastrointestinal effects, nervous system disorders (from loss of 
function to tremor and numbness), skin irritation, and reproductive and 
developmental disorders. Additionally, several of the metals accumulate 
in the environment and in the human body. Cadmium, for example, is a 
cumulative pollutant, which can cause kidney effects after the 
cessation of exposure. Similarly, the onset of effects from beryllium 
exposure may be delayed months to years. Metals and metal compounds 
that would be reduced by this proposed rule are also known (arsenic and 
chromium) and probable (beryllium and cadmium)human carcinogens.
    Mercury, a volatile metal, would also be reduced by the proposed 
standard. All forms of mercury may be characterized as quite toxic, 
with different health effects associated with different forms of the 
pollutant. Methyl mercury is the most toxic form of mercury to which 
humans and wildlife are generally exposed. Exposure to methyl mercury 
occurs primarily through ingestion of fish. Methyl mercury primarily 
effects the nervous systems in humans. The range of neurotoxic effects 
can vary from subtle decrements in motor skills and sensory ability to 
tremors, inability to walk, convulsions, and death. Exposure to 
inorganic mercury is associated with renal impairment. Some forms of 
mercury have also been classified as possible human carcinogens. 
Exposure to mercury compounds can also cause effects in plants, birds, 
and non-human mammals. Reproductive effects are the primary concern for 
avian mercury poisoning.
    The organic compound that would be reduced by this standard is 
MIBK. Some of the human health effects associated with short-term 
exposure, at some level, to this pollutant include irritation to the 
eyes and mucous membranes, weakness, headache, nausea, lightheadedness, 
dizziness, incoordination, and narcosis. Long-term occupational 
exposure has been observed to cause nausea, headache, burning in the 
eyes, weakness, insomnia, intestinal pain, and slight enlargement of 
the liver in humans. No information is available on the carcinogenic 
effects of MIBK in humans.

D. Phosphoric Acid Manufacturing and Phosphate Fertilizers Production 
Industry Profile

    This section includes general overviews of the two source 
categories for which NESHAP are being proposed. Phosphoric acid is 
manufactured by way of two process approaches. One approach is the 
thermal process whereby purified elemental phosphorous is combusted and 
hydrated to directly form phosphoric acid. There are currently ten 
facilities operating in the United States. For the period from 1971-
1991, nationwide production of phosphoric acid via the thermal process 
declined by forty-seven percent and this trend is expected to continue. 
No new thermal process plants are expected to be constructed. The 
decline in usage of this process may be attributed to price competition 
by competitive products, energy costs associated with production of 
feedstock phosphorous and safety concerns with regard to shipping 
phosphorous.
    The second means of manufacturing phosphoric acid is through wet 
processes. There are 47 wet acid plants at 21 locations. The basic step 
for producing phosphoric acid is the acidulation of phosphate rock. 
Typically, sulfuric acid, phosphate rock and water are reacted with one 
another to produce phosphoric acid and gypsum. When phosphate rock is 
acidulated to manufacture wet process phosphoric acid (WPPA), fluorine 
contained in the rock is released. Fluoride compounds, including HF, 
are evolved as particulates and gases which are emitted to the 
atmosphere unless removed from the exhaust stream. Some of these same 
fluoride compounds also remain in the product acid and are available 
for release as air pollutants during subsequent processing of the acid. 
Gypsum is pumped as a slurry to ponds atop stacks of waste gypsum where 
the liquids separate from the slurry and are decanted for return to the 
process with process cooling water. The gypsum is discarded as a major 
solid waste stream. There are 13 acid plants at eight locations which 
concentrate WPPA to make superphosphoric acid (SPA). Most producers use 
the vacuum evaporation process. One manufacturer uses the submerged 
combustion process to achieve the same effect.
    The bulk of WPPA is used to produce fertilizers and animal feeds. 
In addition, two companies now use solvent extraction processes to 
further refine WPPA into purified phosphoric acid (PPA) for use in food 
manufacturing or specialized chemical processes. Purified phosphoric 
acid produced through wet processes now competes directly with acid 
produced by the thermal process.
    There are two major processes employed for the production of 
phosphate fertilizers. One produces ammoniated phosphate fertilizers in 
the form of either diammonium phosphate (DAP) or monoammonium phosphate 
(MAP). Approximately 85 percent of all ammonium phosphates are produced 
as DAP. Diammonium phosphate and MAP

[[Page 68433]]

plants are generally collocated with wet-process phosphoric acid 
plants. Forty individual production units for DAP or MAP are located at 
22 facilities. Plants that produce DAP and MAP are generally co-located 
with wet-process phosphoric acid plants. Most facilities can produce 
either product in the same process train.
    Diammonium phosphate and MAP are manufactured from phosphoric acid 
and ammonia. The process consists of three basic steps: reaction, 
granulation, and finishing operations such as drying, cooling, and 
screening. Side reactions resulting from the production of ammonium 
phosphates produce ammonium fluoride, ammonium sulfate, and ammonium 
fluorosilicate. In addition, some of the fluorine is liberated as 
SiF4 and HF. Sources of fluoride emissions from DAP/MAP plants 
include the reactor, granulator, dryer, cooler, screens, and mills.
    The second major process employed in the phosphate fertilizers 
industry produces granular triple superphosphate (GTSP). Ten production 
units at seven facilities produce GTSP in the U.S. The primary raw 
materials used to produce GTSP are WPPA and ground phosphate rock. 
Plants that produce GTSP are generally collocated with wet-process 
phosphoric acid plants. Granular triple superphosphate is an impure 
monocalcium phosphate made by reacting phosphoric acid with ground 
phosphate rock. After manufacture, the product is sent to a storage 
building by a conveyor belt which discharges the material into bins or 
piles for curing. The GTSP is typically held five to ten days to 
stabilize the composition, after which it is considered cured and ready 
for shipping. Sources of emissions from GTSP plants include the 
reactor, the granulator, the dryer, the cooler, the screening and 
crushing equipment, and the storage building. Fluorides are emitted in 
both gaseous and particulate form. The reactor and granulator account 
for about 38 percent of the fluoride emissions; the dryer and screens 
account for 50 percent, and the storage facilities account for the 
remainder.

III. Summary of Proposed Standards

A. Applicability

    The proposed standards apply to affected sources at each existing, 
modified, reconstructed, and newly constructed phosphoric acid 
manufacturing plant and each phosphate fertilizers production plant. 
All phosphoric acid manufacturing and phosphate fertilizers production 
plants that are major sources of HAPs would be subject to the 
standards. Provisions are included in the NESHAP General Provisions (40 
CFR part 63, subpart A) for the owner or operator to obtain a 
determination of applicability. A facility that is determined by EPA to 
be an area source would not be subject to the NESHAP.

B. Emission Limits and Requirements

    The emissions levels being proposed for NESHAP for existing and new 
sources are given in the tables below. The permit information and test 
data used to select these proposed limits are presented in the TSD 
referenced above. The rationale for selection of the individual 
emissions limits is explained in section V.C. of this notice.

       Proposed Emissions Limitations for Existing Phosphoric Acid      
          Manufacturing Plants and Phosphate Fertilizers Plants         
------------------------------------------------------------------------
                                                       Proposed emission
         Class of source               Pollutant             limit      
------------------------------------------------------------------------
Wet Process Phosphoric Acid       Total Fluorides...  0.020 lb. Total   
 Plant.                                                Fluoride (F-)Per 
                                                       Ton P2O5 Feed.   
Superphosphoric Acid Plant......  Total Fluorides...  0.010 lb. F- Per  
                                                       Ton P2O5 Feed.   
Diammonium and/or Monoammonium    Total Fluorides...  0.060 lb. F- Per  
 Phosphate Plant.                                      Ton P2O5 Feed.   
Granular Triple Superphos-phate   Total Fluorides...  0.150 lb. F- Per  
 Plant.                                                Ton P2O5 Feed.   
Granular Triple Superphos-phate   Total Fluorides...  5.0 X 10-4 lb. F- 
 Storage Buildings.                                    Per Hour Per Ton 
                                                       of P2O5 Stored.  
Phosphate Rock Dryers...........  Particulate Matter  0.2150 lb. PM Per 
                                                       Ton of Rock Feed.
Phosphate Rock Calciners........  Particulate Matter  0.060 grains PM   
                                                       Per Dry Standard 
                                                       Cubic Foot.      
Purified Phosphoric Acid Plants.  MIBK..............  0.168640 lb. MIBK 
                                                       Per Ton P2O5     
                                                       Feed.            
------------------------------------------------------------------------


  Proposed Emissions Limitations for New Phosphoric Acid Manufacturing  
                 Plants and Phosphate Fertilizers Plants                
------------------------------------------------------------------------
                                                       Proposed emission
         Class of source               Pollutant             limit      
------------------------------------------------------------------------
Wet Process Phosphoric Acid       Total Fluorides...  0.01350 lb. Total 
 Plant.                                                Fluoride (F-) per
                                                       ton P2O5 Feed.   
Superphos-phoric Acid Plant.....  Total Fluorides...  0.00870 lb. F- per
                                                       ton P2O5 Feed.   
Diammonium and/or Monoammonium    Total Fluorides...  0.0580 lb. F- per 
 Phosphate Plant.                                      ton P2O5 Feed.   
Granular Triple Superphos-phate   Total Fluorides...  0.1230 lb. F- per 
 Plant.                                                ton P2O5 Feed.   
Granular Triple Superphos-phate   Total Fluorides...  5.0 x 10-4 lb. F- 
 Storage Buildings.                                    Per Hour Per Ton 
                                                       of P2O5 Stored.  
Phosphate Rock Dryers...........  Particulate Matter  0.060 lb. PM Per  
                                                       Ton of Rock Feed.
Phosphate Rock Calciners........  Particulate Matter  0.040 grains PM   
                                                       Per Dry Standard 
                                                       Cubic Foot.      
Purified Phosphoric Acid Plants.  MIBK..............  0.168640 lb. MIBK 
                                                       Per Ton P2O5     
                                                       Feed.            
------------------------------------------------------------------------

C. Performance Test and Compliance Provisions

    A one-time performance test would be required to demonstrate 
initial compliance with each applicable numerical limit for total 
fluorides or particulate matter. The owner/operator would be required 
to record process and control device operating parameters during the 
performance test. The owner/operator would be required to maintain 
scrubber pressure drop and liquid flow rate within plus or minus ten 
percent of the values recorded during the performance test. Any 
exceedance of that operating range would be considered a violation of 
the applicable standard. A source would be allowed up to 30 days to re-
test and demonstrate compliance with the numerical limit of the 
standard. As an alternative to the preceding, the proposed regulations 
would provide sources the option of establishing ranges of the control 
device operating ranges on the basis of data derived from previous 
performance tests

[[Page 68434]]

or specially-conducted performance tests. Any exceedance of those 
ranges would be considered a violation of the numerical limit of the 
applicable standard.
    Compliance with the limitations upon MIBK emissions would be 
established through inventory and production records and through daily 
measurements of process parameters.

D. Monitoring Requirements

    The proposed monitoring provisions require the owner or operator to 
continuously monitor the pressure drop and liquid flow rate of 
scrubbing devices used to control total fluorides or particulate 
matter. The feed rate of raw materials to the processes would also be 
continuously monitored.
    For PPA plants that emit MIBK, the standards would require 
continuous monitoring of chiller stack temperature and daily monitoring 
of MIBK concentrations at two points in the process.
    As required by the NESHAP General Provisions (40 CFR part 63, 
subpart A), the owner or operator also must develop and implement a 
Startup, Shutdown, and Malfunction Plan.

E. Notification, Recordkeeping, and Reporting Requirements

    All notification, recordkeeping, and reporting requirements in the 
General Provisions would apply to phosphoric acid manufacturing and 
phosphate fertilizers production facilities. These include: (1) initial 
notification(s) of applicability, notification of performance test, and 
notification of compliance status; (2) a report of performance test 
results; (3) a Startup, Shutdown, and Malfunction Plan with semiannual 
reports of reportable events (if they occur); and (4) semiannual 
reports of excess emissions. If excess emissions are reported, the 
owner or operator must report quarterly until a request to return the 
reporting frequency to semiannual is approved.
    The NESHAP General Provisions (40 CFR part 63, subpart A) require 
that records be maintained for at least 5 years from the date of each 
record. The owner or operator must retain the records on site for at 
least 2 years but may retain the records off site the remaining 3 
years. The files may be retained on microfilm, microfiche, on a 
computer, on computer disks, or on magnetic tape disks. Reports may be 
made on paper or on a labeled computer disk using commonly available 
and compatible computer software.

IV. Selection of Proposed Standards

A. Selection of Source Categories

    Section 112(c) of the Act directs the Agency to list each category 
of major and area sources, as appropriate, emitting one or more of the 
189 HAPs listed in section 112(b) of the Act. The EPA published an 
initial list of source categories on July 16, 1992 (57 FR 31576), and 
may amend the list at any time. ``Phosphoric acid manufacturing and 
phosphate fertilizers production'' are two of the 174 categories of 
sources listed in the notice.
    For this study, EPA collected information and data through the 
following: (1) review of existing literature; (2) visits to State air 
pollution control agencies to obtain plant-specific test data and 
permits; (3) visits to three plant sites; (4) meetings with 
representatives of individual companies; (5) meetings with The 
Fertilizer Institute, an industry trade organization; and (8) meetings 
with State air pollution control agency personnel. Based on this 
information and data, EPA believes that 15 facilities may be major 
sources subject to the NESHAP. As defined in the Act, a major source 
must have the potential to emit 9.1 Mg/yr (10 tpy) or more of a single 
HAP or 22.7 Mg/yr (25 tpy) or more of a combination of HAPs.
    On December 3, 1993 (58 FR 63941), EPA published a schedule for the 
promulgation of standards for the sources selected for regulation under 
section 112(c) of the Act. According to this schedule, MACT standards 
for this source category must be promulgated no later than November 15, 
2000. If standards are not promulgated by May 15, 2002 (18 months 
following the promulgation deadline), section 112(j) of the Act 
requires States or local agencies with approved permit programs to 
issue permits or revise existing permits containing either an 
equivalent emission limitation or an alternate emission limitation for 
HAP control.
    Section 112 of the Act requires the Agency to establish national 
standards to reduce air emissions from major sources and certain area 
sources that emit one or more HAP. Section 112(b) contains a list of 
HAP to be regulated by NESHAP. Section 112(c) directs the Agency to use 
this pollutant list to develop and publish a list of source categories 
for which NESHAP will be developed and a schedule for development of 
those NESHAP. The Agency must list all known source categories and 
subcategories of ``major sources'' that emit one or more of the listed 
HAP. A major source is defined in section 112(a) as any stationary 
source or group of stationary sources located within a contiguous area 
and under common control that emits or has the potential to emit in the 
aggregate, considering controls, 10 tons per year or more of any one 
HAP or 25 tons per year or more of any combination of HAP. This list of 
source categories was published in the Federal Register on July 16, 
1992 (57 FR 31576) and includes phosphoric acid manufacturing and 
phosphate fertilizers production.
    For area sources, the Agency examined available data on facilities, 
emissions, and health and environmental effects of emitted HAPs and 
concluded that there is no threat of adverse effects to human health or 
the environment from the area sources in these two source categories. 
Consequently, the Agency decided not to list the area sources.

B. Selection of Emission Sources and Pollutants

    While phosphoric acid manufacturing and phosphate fertilizers 
production facilities are listed separately for the purposes of section 
112 (c) of the Act, they are generally collocated. Phosphoric acid 
manufacturing facilities provide feedstock for phosphate fertilizer 
production facilities and much of the phosphoric acid produced in the 
United States is consumed in the manufacture of fertilizers. Thus, the 
Agency has chosen to regulate component processes of both source 
categories through a combined rulemaking action. This course of action 
was previously adopted when the Agency promulgated new source 
performance standards (NSPS) (see 40 FR 33152) to limit emissions of 
total fluoride compounds (which include the HAP HF) from several 
processes in the phosphate fertilizers industry. The NSPS apply to 
processes units producing WPPA, SPA, DAP, and GTSP, including GTSP 
storage buildings.
    Once source categories have been listed as major for one or more 
HAPs, the Act requires that the Agency establish emission limits for 
all HAP-emitting units at sources within the source category regardless 
of whether or not those individual units emit HAPs in major quantities. 
An exception to this occurs when the Agency has listed specific types 
of sources as major sources and is developing a separate rule for those 
individual sources. Examples are boilers and cooling towers. For 
phosphoric acid manufacturing, the Agency explored the need to 
establish standards for phosphate rock drying and calcination (arsenic, 
beryllium, cadmium,

[[Page 68435]]

chromium, manganese, mercury, and nickel (HAP metals) emissions), WPPA 
manufacturing (HF emissions), SPA manufacturing (HF emissions), thermal 
process SPA (phosphorous emissions), and solvent extracted SPA (methyl 
isobutyl ketone (MIBK) emissions) which is commonly referred to as 
purified phosphoric acid (PPA).
    A review of information for existing thermal process acid plants 
indicated that none are major sources of HAP emissions nor are they 
collocated with major sources. The potential for emissions of the HAP 
phosphorous is quite minimal because phosphorous is extremely reactive 
with oxygen and, therefore, does not exist in nature as a pure 
substance. Many plants previously in service have been closed due to 
economic pressures and no new ones are expected to be built. Since no 
existing thermal process plants are major sources and no new ones are 
to be built, there is no benefit to be derived from the development of 
applicable NESHAP. Given that the manufacture of WPPA, SPA, and PPA 
cause emission of significant quantities of HAPs and the availability 
of emission control systems, the Agency elected to develop and propose 
NESHAP for manufacture of those three products.
    The phosphate fertilizers production source category potentially 
includes production of DAP, MAP, GTSP, normal superphosphate (NSP), and 
ammonium polyphosphate (APP). No NESHAP were developed for the NSP 
process because no production occurs at major sources and no stand-
alone major sources were identified. Standards were not developed for 
APP production because the pollutant of concern is ammonia which is not 
a listed HAP. For the other phosphate fertilizers production processes, 
emissions limits were developed and are being proposed in today's 
action.
    Today's action proposes NESHAP that would be applicable to new and 
existing major sources emitting HAP from the phosphoric acid 
manufacturing and phosphate fertilizers production source categories. 
For major sources, the rules would apply to each of the following 
affected sources: (1) WPPA plants; (2) SPA plants; (3) PPA plants; (4) 
phosphate rock dryers; (5) phosphate rock calciners; (6) DAP/MAP 
plants; (7) GTSP plants; and (8) GTSP storage facilities. The proposed 
emission limits are based on an analysis of the available emission test 
data from the various types of sources present in the source 
categories. Except for PPA plants, phosphate rock dryers, and phosphate 
rock calciners, the potentially affected units listed above are subject 
to NSPS and State regulations which limit emissions of total fluorides. 
The Agency test methods used to determine compliance with the NSPS 
measure total fluoride and are not specific to the HAP HF. At the time 
data were collected for this action, many sources affected by today's 
proposal were subject to either NSPS or State regulations. No 
performance test data were provided which specifically measured the HAP 
HF. Therefore, the database contains many performance tests for total 
fluorides and none for HF. To support a State air toxics permit 
application, one company performed tests which indicated that the HF 
content of emissions from WPPA plants can vary from 28 to 49 percent of 
total fluoride emissions depending upon whether the phosphate rock has 
been calcined (docket item II-I-32 cc). Since the wet scrubbing systems 
used for control of total fluorides are effective at reducing HF 
emissions, the Agency chose to use total fluorides as a surrogate for 
HF for those classes of sources for which HF is the regulated 
pollutant. This approach allows use of the available test data for 
establishing the MACT level of control and it provides consistency with 
current Federal and State permits. It would also result in a common 
basis for permitting in those cases where sources would continue to be 
covered by existing regulations but not be subject to NESHAP due to 
their nonmajor status.
    Particulate emissions from phosphate rock dryers and calciners, 
contain HAP metals. Particulate matter emissions from dryers include 
arsenic, beryllium, cadmium, chromium, manganese, mercury, and nickel. 
Particulate matter emissions from calciners include arsenic, beryllium, 
chromium, manganese, mercury, and nickel. However, there are no stack 
test data specific to HAP metals. All permits and test data are for 
particulate matter. In the absence of detailed information on HAP 
metals emissions, the MACT floor has been determined using particulate 
matter as a surrogate for HAP metals. Accordingly, the proposed 
emissions limits are expressed as particulate matter.
    One PPA plant is a major source of MIBK emissions. For that source, 
there is sufficient information to directly establish NESHAP for MIBK.

C. Selection of Proposed Standards for Existing and New Sources

1. Background
    After EPA has identified the specific source categories or 
subcategories of major sources to regulate under section 112, it must 
set MACT standards for each category or subcategory. Section 112 
establishes a minimum baseline or ``floor'' for standards. For new 
sources, the standards for a source category or subcategory cannot be 
less stringent than the emission control that is achieved in practice 
by the best-controlled similar source. [See section 112(d)(3).] The 
standards for existing sources can be less stringent than standards for 
new sources, but they cannot be less stringent than the average 
emission limitation achieved by the best-performing 12 percent of 
existing sources for categories and subcategories with 30 or more 
sources, or the best-performing 5 sources for categories or 
subcategories with fewer than 30 sources.
    After the floor has been determined for a new or existing source in 
a source category or subcategory, the Administrator must set MACT 
standards that are no less stringent than the floor. Such standards 
must then be met by all sources within the category or subcategory. In 
establishing the standards, EPA may distinguish among classes, types, 
and sizes of sources within a category or subcategory. [See section 
112(d)(1).]
    The next step in establishing MACT standards is traditionally the 
investigation of regulatory alternatives. With MACT standards, only 
alternatives at least as stringent as the floor may be selected. 
Information about the industry is analyzed to develop model plants for 
projecting national impacts, including HAP emission reduction levels 
and cost, energy, and secondary impacts. Several regulatory alternative 
levels (which may be different levels of emissions control, equal to or 
more stringent than the floor levels) are then evaluated to select the 
regulatory alternative that best reflects the appropriate MACT level. 
The selected alternative may be more stringent than the MACT floor, but 
the control level selected must be technically achievable. The 
regulatory alternatives selected for new and existing sources may be 
different because of different MACT floors, and separate regulatory 
decisions may be made for new and existing sources.
    The Agency may consider going ``beyond-the-floor'' to require more 
stringent controls. Here, EPA considers the achievable emission 
reductions of HAPs (and possibly other pollutants that are co-
controlled), cost and economic impacts, energy impacts, and other non-
air environmental impacts. The objective is to achieve the maximum 
degree of emissions reduction without unreasonable economic or other 
impacts. [See section 112(d)(2).]

[[Page 68436]]

    Subcategorization within a source category may be considered only 
when there is enough evidence to demonstrate clearly that there are 
significant differences among the subcategories. The criteria to 
consider include process operations (including differences between 
batch and continuous operations), emission characteristics, and control 
device applicability.
    The EPA examined the processes, the process operations, and other 
factors to determine if separate classes of units, operations, or other 
criteria have an effect on air emissions. For phosphoric acid 
manufacturing and phosphate fertilizers production plants, 
characteristics of emissions streams and, therefore, effectiveness of 
control technologies are differentiated by the products being 
manufactured. Thus, in this rulemaking, the Agency has adopted the 
overall approach used in the previous development of NSPS and developed 
proposed emissions limits for major unit operations that manufacture 
specific products.
2. Emission Limits--General
    For existing sources, Sec. 112(d)(3) of the Act requires that the 
Agency establish NESHAP no less stringent than ``the average emission 
limitation achieved by the best performing 12 percent of the existing 
sources (for which the Administrator has information).'' This language 
has led to two differing interpretations of the intent of the CAA 
language. One interpretation is that the Act requires the Agency to 
establish MACT on the basis of permitted emissions limits. The other 
interpretation holds that MACT must be established on the basis of 
actual emissions as established through emissions test data. In the 
document ``Municipal Waste Combustion: Background Information for 
Promulgated Standards and Guidelines--Summary of Public Comments and 
Responses,'' EPA-453/R-95-0136, October 1995, published in support of 
the December 19, 1995 Federal Register notice (60 FR 65387) for 
promulgated standards of performance for new municipal waste combustors 
(MWC) and emission guidelines for existing MWC, the Agency discussed 
the legislative history and relevant case law at some length. In that 
discussion, the Agency concluded that Congress did not directly speak 
to the question at issue. The discussion was focused upon Sec. 129 of 
the Act. Since sections 129 and 112 are quite similarly worded, the 
same approach is being applied in this instance. Accordingly, the 
Agency has applied the test from Chevron v. NRDC, 467 U.S. 837 (1984) 
that its interpretation of the Act must be a ``permissible 
construction'' of the statute.
    In this instance, the Agency first notes that it was the clear 
intent of Congress that, when possible, NESHAP are to be numerical 
limitations derived from the application of emissions control 
technologies. As was described above, for existing sources, the 
limitations may be no less stringent than the average level of control 
achieved by the best controlled twelve percent of those sources. This 
is commonly referred to as the MACT floor. As a starting point, the 
Agency attempted to identify the technology applied to achieve the 
lowest emissions. Since the HAP HF was the main concern for this 
standard, the initial approach was focused upon determining MACT for 
HF. The same approach was later extended to HAP metals for subsequent 
analyses. After thoroughly searching for studies which directly 
measured stack emissions of HF, the Agency concluded that there is a 
paucity of definitive data as to the exact amount of HF actually being 
emitted, although, as was previously noted, the HF content potentially 
ranges from 28 to 49 percent of total fluoride. This finding led the 
Agency to look for other means to establish a technical basis for 
NESHAP. During its information collection effort, the Agency found that 
there is a large body of existing data for the surrogate pollutant 
total fluoride, which the Agency previously designated for control 
under Sec. 111 of the Act through the development of NSPS. Those NSPS 
are emissions limitations based upon demonstrated technologies. Given a 
paucity of direct data on HF emissions and a large body of data 
developed to demonstrate achievement of permitted emissions which 
include HF as a component of total fluorides, the Agency chose to use 
total fluoride as a surrogate for HF in its analyses. By adopting the 
approach of regulating total fluoride as surrogate for HF, the Agency 
avails itself of information reflecting the effect of over twenty years 
of implementation of NSPS and emissions guidelines (EG) which are 
technology-based standards. The Agency has obtained a wealth of 
performance data derived from emissions tests conducted to establish 
compliance with permitted emissions limitations required by NSPS and 
with State-permitted emissions limitations developed pursuant to EG for 
previously existing sources. Reviewing this information base reveals 
that, in general, the best controlled sources for the various processes 
used differently configured combinations of wet scrubbing devices. 
Several different types and configurations of wet scrubbing devices 
were found to give high levels of removal of fluorides. For most 
sources, the control systems were designed to achieve emissions limits 
equal to or more stringent than the NSPS. For this rulemaking, the 
Agency has concluded that permitted emissions constitute the emissions 
limits which the technological controls were designed to achieve. To 
determine emissions limits corresponding to MACT floors, the Agency 
first identified the median of the top twelve percent of permits issued 
for the best controlled sources for each process. Generally, this 
resulted in the identification of the third of the five most 
stringently permitted sources for a given process. After thus 
identifying the best controlled sources and establishing preliminary 
MACT floors, the Agency then used the available test data to ascertain 
that the permit limits were being achieved and to determine if greater 
degrees of control were actually being achieved in practice. For 
sources of total fluorides, the range of the available test data showed 
that the permitted emissions were reflective of the degree of emissions 
control actually being achieved.
    For phosphate rock dryers and calciners, the MACT floors were 
established using particulate matter as a surrogate for HAP metals. For 
dryers, there was very little available test data. So, the MACT floor 
analysis was performed using permitted emissions of particulate matter. 
For calciners, there were numerous test reports for particulate matter. 
The permits for calciners were all based upon general process rate 
allowances which were not developed specifically for phosphate rock 
calcining. Test data showed that the permits do not reflect the level 
of emissions reductions achieved in practice. So, for calciners, the 
MACT analysis was based upon the test data.
    One source manufactures a purified phosphoric acid through a 
solvent extraction method. The plant emits MIBK, which is a HAP. The 
source has modified its process several times to improve capacity and 
there is no information which the Agency can use to determine the 
effects of those modifications upon emissions as determined from 
inventory records. Therefore, MACT was determined on the basis of the 
original permitted emissions. Those limits were based upon the 
engineering design of the controls built into the plant. To that 
permitted amount, the Agency added an allowance for fugitive emissions 
of

[[Page 68437]]

MIBK known to occur because of utilization of a waste stream in an 
adjoining fertilizer plant. The permitted emissions were added to the 
fugitives and divided by permitted production capacity to calculate a 
unit emissions factor for MIBK based upon the input of P2O5.
    For new sources, the most stringent permit issued for any given 
process was adopted as MACT, except for calciners. The calciners limit 
was based upon test data. Performance test data are presented in the 
TSD and show that the most stringent permit limits are being achieved 
in practice.
    Having thus identified the floor level of control, the Agency then 
considered the possibility of setting more stringent limitations. As a 
part of that consideration, the Agency modeled MACT floor level 
emissions of HF for the purpose of quantifying potential health 
concerns. For HF, there is no Agency-approved health bench mark with 
which to identify potential public exposure and risk problems. A 
screening level exposure analysis was performed using State agency 
health bench marks and no health concerns were identified (docket item 
II-B-14). In addition, the Agency reviewed a detailed exposure and risk 
assessment performed for a source subject to State air toxics 
requirements which reached this same conclusion (docket item II-I-32 
cc). Besides exploring potential health impacts for HF, the Agency also 
examined modeling performed by a source for trace metal emissions from 
calciners subject to the MACT floor level of control. Estimated health 
risks were minimal. None of the health impacts analyses for existing 
sources indicated a need to control emissions beyond the levels 
corresponding to the MACT floors. Therefore, the Agency proposes to 
establish limits for existing major sources at the floor levels.
    During the analysis of public health impacts, the Agency also 
considered the need for area source standards. A screening level 
exposure analysis using a ten ton per year of HF model plant and State 
agency health bench marks did not identify ``a threat of adverse 
effects to human health or the environment (by such sources 
individually or in the aggregate).'' Therefore, the Agency does not 
recommend listing area sources and developing standards.
3. Emission Limits for Classes of Sources
    WPPA Plants. The Agency previously promulgated NSPS which limit 
emissions of total fluorides. Those NSPS appear in 40 CFR Subpart T. 
For NSPS purposes, a WPPA plant is defined as any plant manufacturing 
phosphoric acid by reacting phosphate rock and acid. This same 
definition is applied herein. The NSPS limit total fluoride emissions 
to 0.02 pounds per ton of P2O5 fed to the process. At this 
time there are 35 WPPA plants and permitted emissions range from 0.0135 
to 0.69 pounds of total fluoride per ton of P2O5 fed to the 
process. Twenty five of those plants are permitted at limits equivalent 
to or more stringent than the NSPS. All plants employ wet scrubbing 
devices to control total fluoride emissions.
    The Act requires that the MACT floor for existing sources in 
categories with 30 or more sources must be no less stringent than the 
average emission limitation achieved by the best performing 12 percent 
of those sources. In this instance, the best performing sources are all 
subject to permit provisions requiring that they achieve emissions 
limitations equivalent to or more stringent than the NSPS. For those 
plants, permitted emissions range from 0.01350 to the NSPS limit of 
0.020 pounds of total fluoride per ton of P2O5 fed to the 
process. The median of these permit limits is at the NSPS level of 
control and this was selected as the MACT floor level. The available 
test data summarized in the TSD show that the plants which form the 
basis for the MACT floor are achieving the NSPS level of control. 
Tested emissions for all plants permitted at or below the MACT floor 
range from 0.0004 to 0.019 pounds of total fluoride per ton of 
P2O5 fed to the process. Thus, the emissions limit 
corresponding to the MACT floor, which is the NSPS, is being proposed 
as MACT for existing WPPA plants.
    For new sources, MACT must be as stringent as the emission 
limitation that is achieved in practice by the best controlled similar 
source, as determined by the Administrator. Currently, the most 
stringent permit for a WPPA plant is for the Cargill Industries 
facility in Riverview Florida which has been permitted at an emission 
limitation of 0.01350 pounds of total fluoride per ton of 
P2O5 fed to the process. Therefore, this limit is being 
proposed for new WPPA plants.
    During the development of NESHAP, the Agency examined the emission 
of HF from gypsum and cooling pond systems. Recent testing of pond 
systems was performed using long path Fourier transform infra-red 
spectroscopy to typify emissions of HF (docket item II-D-15). The tests 
indicted that although small quantities of HF may be evolved from pond 
surfaces, the measured quantities would not be significant in 
comparison to overall process emissions. The Agency did investigate 
options for treating pond water to further minimize HF emissions 
(docket item II-B-9). None of the technologies considered have been 
successfully demonstrated on a commercial basis when applied to the 
ores and processes common to the United States. Thus, the Agency 
concluded that MACT for pond systems is no control.
    All the plants which are being used to define MACT discharge 
scrubber effluent to cooling ponds. Four sources subject to the NSPS 
pump effluent from scrubbers to evaporative cooling towers where the 
collected fluorides are subjected to air stripping. This practice 
renders the air pollution controls largely ineffective for their 
intended purpose. Accordingly, the proposed NESHAP specifically 
prohibits this practice. The plants affected by the proposed NESHAP 
have other options available, such as discharging scrubber effluents to 
gypsum ponds. This requirement would be applied to both WPPA and SPA 
plants. The Agency notes that this provision will apply only to liquid 
discharges from air pollution control devices and is not intended to 
apply to process equipment.
    SPA Plants. The Agency previously promulgated NSPS which limit 
emissions of total fluorides. Those NSPS appear in 40 CFR Part 60, 
Subpart U. The NSPS limit total fluoride emissions to 0.01 pounds per 
ton of P2O5 fed to the process. For NSPS purposes, an SPA 
plant is defined as any facility which concentrates WPPA to 66 percent 
or greater P2O5 content for eventual consumption as 
fertilizer. For purposes of the proposed NESHAP, the basic NSPS 
definition for the plant will be adopted but it will not be limited to 
production of SPA for consumption as fertilizer. The end use of the 
manufactured SPA is not relevant to the need to control HAP emissions 
pursuant to the Act. With the exception of one source employing the 
submerged combustion process, all producers in the United States employ 
vacuum evaporation to make SPA. The best-controlled plants for which 
data were available use the vacuum evaporation process. There are 
twelve SPA plants using vacuum evaporation and permitted emissions 
range from 0.0087 to 1.1 pounds of total fluoride per ton of 
P2O5 fed to the process. Nine of those plants are permitted 
at limits equivalent to or more stringent than the NSPS. All plants 
employ wet scrubbing devices to control total fluoride emissions. 
Several different scrubber designs are employed.
    The Act requires that the MACT floor for existing sources in 
categories with fewer than 30 sources must be no less stringent than 
the average emission

[[Page 68438]]

limitation achieved by the best performing five of those sources. In 
this instance, the five best performing sources are all subject to 
permit provisions requiring that they achieve emissions limitations 
equivalent to or more stringent than the NSPS. The median of these 
permit limits is at the NSPS level of control, 0.01 pounds per ton of 
P2O5 fed to the process, and this was selected as the MACT 
floor level. The available test data summarized in the TSD show that 
the plants which form the basis for the MACT floor are achieving the 
NSPS level of control. Tested emissions for all plants permitted at or 
below the MACT floor range from 0.00013 to 0.00847 pounds of total 
fluoride per ton of P2O5 fed to the process. Thus, the 
emissions limit corresponding to the MACT floor, which is the NSPS, is 
being proposed as MACT for existing SPA plants that use the vacuum 
evaporation process.
    The one source which manufactures SPA using a variation of the 
submerged combustion process requested that the Agency consider a 
separate subcategory for the process on the basis that a combination of 
feedstock, final product, and process requirements uniquely influences 
the level of control achievable at that site. The source provided 
information (docket item II-D-52) showing that their imported feedstock 
differs from that of other domestic producers of SPA in that it 
contains lesser amounts of impurities including radium and magnesium. 
The lesser amounts of radium are beneficial from the perspective that 
this reduces the radioactivity of the phosphogypsum waste material 
resulting from the processes. The lowered magnesium content is 
important to customers with whom the source has contractual 
obligations. The negative result of the lesser magnesium content is 
that it causes increased corrosivity of the acid manufactured at that 
site. Engineering studies have been unable to resolve the corrosion 
problem and, so, the source cannot readily convert its production to 
the vacuum evaporation process. In discussions with its State agency, 
the source has committed itself to install new air pollution controls 
and has performed engineering analyses which indicate that the source 
cannot meet the MACT performance level of the vacuum evaporation 
process. The potential to meet a level of 0.20 pounds of total fluoride 
per ton of P2O5 fed to the process has been successfully 
tested in a pilot test. In consideration of the overall environmental 
and technical factors unique to the existing operations of that source, 
the Agency has determined that subcategorization of that one existing 
source is appropriate and that MACT is 0.20 pounds of total fluoride 
per ton of P2O5 fed to the process for existing operations. 
For a new SPA plant at that site, the Agency would expect that the 
source could avail itself of the same resources as other companies in 
the industry and that no special consideration would be appropriate.
    For new sources, MACT must be as stringent as the emission 
limitation that is achieved by the best controlled similar source, as 
determined by the Administrator. Currently, the best controlled SPA 
plant achieves a permitted emission limit of 0.0087 pounds of total 
fluoride per ton of P2O5 fed to the process. Emissions test 
data confirm that this level of control is being achieved in practice. 
Therefore, this limit is being proposed for new SPA plants.
    DAP/MAP Plants. The Agency previously promulgated NSPS which limit 
emissions of total fluorides from DAP production. Those NSPS appear in 
40 CFR Part 60, Subpart V. The NSPS limit total fluoride emissions to 
0.06 pounds per ton of P2O5 fed to the process. For NSPS 
purposes, a DAP plant is defined as any plant manufacturing granular 
DAP by reacting phosphoric acid with ammonia. The NSPS do not include 
MAP production plants as affected facilities. Available information 
shows that many production plants are dedicated to produce either DAP 
or MAP. Other plants are configured and permitted to produce either 
product using the same equipment. As a part of the Agency's MACT 
partnership initiative, the Agency met with State agency and industry 
representatives to discuss issues pertinent to the proposed NESHAP. 
Several discussions addressed the question of whether to have separate 
rules for DAP, MAP and combined DAP/MAP production plants. During those 
discussions it was noted that the plant configurations used to make 
either one or both products are essentially identical. All plants 
employ wet scrubbing devices to control total fluoride emissions. 
Several different scrubber designs were employed. During the MACT 
partnership discussions, the Agency was advised that technical 
considerations cause a dual use production plant to be more difficult 
to control than those dedicated to individual products. All parties to 
the discussion were in agreement that the current NSPS for DAP is 
achievable for DAP, MAP or combined DAP/MAP production. After due 
consideration of these factors, the Agency is proposing that a single 
emissions limitation should be applied to this class of ammoniated 
phosphates. Accordingly, the data for plants permitted to produce both 
products were selected for analysis to establish the MACT floor.
    There are 12 plants permitted to produce both DAP and MAP. For 
those plants, permitted emissions range from 0.0580 to 0.9640 pounds of 
total fluoride per ton of P2O5 fed to the process. The Act 
requires that the MACT floor for existing sources in categories with 
fewer than 30 sources must be no less stringent than the average 
emission limitation achieved by the best performing five of those 
sources. In this instance, the five best performing sources are all 
subject to permit provisions requiring that they achieve emissions 
limitations equivalent to or more stringent than the NSPS. For those 
plants, permitted emissions range from 0.0580 to the NSPS limit of 0.06 
pounds of total fluoride per ton of P2O5 fed to the process. 
The median of these permit limits is at the NSPS level of control and 
this was selected as the MACT floor level. The available test data 
summarized in the TSD show that the plants which form the basis for the 
MACT floor are achieving the NSPS level of control. Tested emissions 
for all plants permitted at or below the MACT floor range from 0.0021 
to 0.0408 pounds of total fluoride per ton of P2O5 fed to the 
process. Thus, the emissions limit corresponding to the MACT floor, 
which is the NSPS, is being proposed as MACT for existing DAP and/or 
MAP plants.
    For new sources, MACT must be as stringent as the emission 
limitation that is achieved by the best controlled similar source, as 
determined by the Administrator. Currently, the best controlled 
combined DAP/MAP plant achieves a permitted emission limit of 0.00580 
pounds of total fluoride per ton of P2O5 fed to the process. 
Emissions test data confirm that this level of control is being 
achieved in practice. Therefore, this limit is being proposed for new 
sources producing DAP and/or MAP.
    GTSP Production Plants. The Agency previously promulgated NSPS 
which limit emissions of total fluorides from triple superphosphate 
production. Those NSPS appear in 40 CFR Part 60, Subpart W. The NSPS 
limit total fluoride emissions to 0.2 pounds per ton of P2O5 
fed to the process. For NESHAP purposes, a GTSP plant would be defined 
as any plant manufacturing GTSP by reacting phosphate rock with 
phosphoric acid. At this time, there are ten GTSP plants and permitted

[[Page 68439]]

emissions range from 0.1230 to 0.760 pounds of total fluoride per ton 
of P2O5 fed to the process. Seven of those plants are 
permitted at limits equivalent to or more stringent than the NSPS. Six 
of those plants are permitted at State limits below the NSPS. All 
plants employ wet scrubbing devices to control total fluoride 
emissions. Several different scrubber designs are employed.
    The Act requires that the MACT floor for existing sources in 
categories with fewer than 30 sources must be no less stringent than 
the average emission limitation achieved by the best performing five of 
those sources. In this instance, the five best performing sources are 
all subject to permit provisions requiring that they achieve emissions 
limitations equivalent to or more stringent than the NSPS. The median 
of the permit limits for the five best controlled existing plants is 
0.150 pounds of total fluoride per ton of P2O5 fed to the 
process and this was selected as representing the MACT floor level of 
control. The available test data summarized in the TSD show that the 
plants which form the basis for the MACT floor are achieving the permit 
limit of 0.150 pounds of total fluoride per ton of P2O5 fed 
to the process in practice. Tested emissions for all plants permitted 
at or below the MACT floor range from 0.00845 to 0.148 pounds of total 
fluoride per ton of P2O5 fed to the process. Thus, an 
emissions limit equivalent to the MACT floor is being proposed for 
existing GTSP plants.
    For new sources, MACT must be at least as stringent as the emission 
limitation that is achieved by the best controlled similar source, as 
determined by the Administrator. Currently, the best controlled GTSP 
plant achieves a permitted emission limit of 0.01230 pounds of total 
fluoride per ton of P2O5 fed to the process. Emissions test 
data confirm that this level of control is being achieved in practice. 
Therefore, this value is being proposed as an emissions limit for new 
GTSP plants.
    GTSP Storage Buildings. The Agency previously promulgated NSPS 
which limit emissions of total fluorides from GTSP storage buildings. 
Those NSPS appear in 40 CFR Part 60, Subpart X. The NSPS limit total 
fluoride emissions to 5.0  x  10-4 pounds per hour per ton of 
P2O5 stored. For NESHAP purposes, the same definition used in 
the NSPS will be used for GTSP storage buildings. At this time there 
are seven GTSP storage buildings in operation. Of the seven, four are 
equipped with wet scrubbers to control fluoride emissions. These 
provide the control technology basis for the MACT floor. In general, 
the permitted emissions limits reflect apportionments assigned by the 
operators to meet emissions limitations for their GTSP plants as a 
whole. Thus, the emissions limits are not based upon the technological 
performance of control systems. The State air pollution control agency 
with jurisdiction over most of the sources was contacted and indicated 
that impacts of emissions from the storage buildings had been 
considered as a part of the overall emissions allowances for the 
fertilizer plants. None of the seven existing GTSP storage buildings is 
subject to the NSPS. Further, the applicable emissions limitations for 
the controlled buildings are in a format which differs from the NSPS. 
Permitted emissions are dependent upon the rate at which GTSP is 
transferred into the buildings. Available data indicate that the actual 
emission rates are comparable to the NSPS limits.
    The Agency previously addressed the issue of determining the best 
technological approach for establishing emission limits for GTSP 
storage buildings during the development of the NSPS in 40 CFR Part 60, 
Subpart X. Those standards reflect the previous judgement of the Agency 
as to the best approach to controlling emissions of total fluorides 
from GTSP storage buildings. That same judgement was reflected in the 
Agency's emissions guidelines for then-existing sources. During 
development of the proposed NESHAP, the Agency requested the opinions 
of State air pollution control agencies and the technical 
representatives of companies which produce phosphate fertilizers. The 
State representatives concluded that the NSPS approach to setting 
emissions limits is preferable to the basis for the permitted emissions 
in that it is clearly based upon technological considerations. The 
industry representatives noted that the NSPS approach accounts for the 
effects of the continued curing of GTSP during initial storage and the 
NSPS also provides consideration of the amount of GTSP stored. Given 
the similarity of the results of the two approaches and the clear 
preference of the involved parties for the NSPS format, the Agency has 
concluded that the NSPS best expresses the MACT floor level of control 
for existing GTSP storage buildings. Should any new GTSP storage 
buildings be placed in service, the Agency continues to believe that 
the NSPS also constitutes the best approach to new source MACT. The 
NSPS is based upon a demonstrated control technology and directly ties 
allowable emissions to the quantity of GTSP in storage. Thus, existing 
and new source MACT is proposed to be a maximum emission of 5.0  x  
10-4 pounds of total fluorides per hour per ton of P2O5 
stored.
    During the development of the NESHAP, the question was raised as to 
whether the proposed NESHAP should be applied to GTSP storage buildings 
which are not co-located with GTSP production plants. The Agency has 
concluded that the proposed NESHAP should only apply to co-located 
storage buildings. The reason for this is that the reactions which 
cause emissions of HF and total fluorides continue for several days 
after newly manufactured GTSP is placed into storage. This is referred 
to as curing. Thus, there is a clear reason to place emissions limits 
upon this class of sources. Opinions differed as to how long 
appreciable emissions are generated. Material handling problems can 
occur if GTSP is shipped from the production plant prior to the 
completion of the curing phase. So, the need for controlling emissions 
during storage coincides with the need to allow time for curing. 
Accordingly there is no benefit to be gained from applying the proposed 
NESHAP to GTSP storage facilities that handle only cured GTSP and are 
not located at GTSP production plants.
    Phosphate Rock Dryers at Phosphoric Acid Manufacturing Plants and 
Phosphate Fertilizers Production Plants. On April 16, 1982, the Agency 
promulgated emissions limits (47 FR 16589) which apply to phosphate 
rock dryers at phosphate rock plants as 40 CFR Part 60 Subpart NN. The 
NSPS limit particulate matter emissions to 0.030 kilogram per megagram 
of phosphate rock feed (0.060 pounds per ton). For NSPS purposes, a 
dryer is defined as a unit in which the moisture content of phosphate 
rock is reduced by contact with a heated gas stream. For the proposed 
NESHAP, the NSPS definition will be adopted. The Agency has found 
little test data for particulate matter emissions. Initially available 
permit information indicated that eight dryers were present at seven 
major sources. One of those dryers is subject to Subpart NN. More 
recent information provided by industry representatives indicates that 
two of those dryers have been demolished and that two others are not 
used as rock dryers. That leaves four dryers from which to establish 
the MACT floor for existing sources.
    The Act requires that the MACT floor for existing sources in 
categories with fewer than 30 sources must be no less stringent than 
the average emission limitation achieved by the best performing five of 
those sources. In this instance, there are only four sources. To

[[Page 68440]]

provide consistency with the methodology used elsewhere in this notice, 
the third or ``median'' dryer was selected as representing the floor 
level of control. That dryer is limited to 0.215 pounds of particulate 
matter per ton of rock fed. With no additional information available, 
the Agency is unable to conclude that a more stringent emissions limit 
is warranted for dryers. Thus, the emissions limit corresponding to the 
MACT floor is being proposed as MACT for existing phosphate rock dryers 
at phosphoric acid manufacturing plants.
    For new sources, MACT must be at least as stringent as the emission 
limitation that is achieved by the best controlled similar source, as 
determined by the Administrator. Currently, the best controlled dryer 
achieves a permitted emission limit of 0.060 pounds of particulate 
matter per ton of rock fed to the process. Emissions test data confirm 
that this level of control is being achieved in practice. Therefore, 
this value is being proposed as MACT for new phosphate rock dryers at 
phosphoric acid manufacturing plants.
    Calciners at Phosphoric Acid Manufacturing Plants. On April 16, 
1982, the Agency promulgated emissions limits (47 FR 16589) which apply 
to phosphate rock calciners at phosphate rock plants as 40 CFR Part 60 
Subpart NN. For NSPS purposes, a calciner is defined as a unit in which 
the moisture and organic matter of phosphate rock is reduced within a 
combustion chamber. For the proposed NESHAP, the NSPS definition will 
be adopted. Information gathered during the development of proposed 
NESHAP show that calciners are present at four major sources. None of 
those calciners are subject to Subpart NN. As previously discussed, the 
Agency chose to use particulate matter as a surrogate for HAP metal 
compounds because no speciated test data were available for calciners. 
All plants use wet scrubbers to control particulate matter. Calciners 
permitted to operate at one source are not in service at this time. A 
second source operates two calciners controlled by wet scrubbers. No 
performance data were available for the second source. A third source 
operates a calciner controlled by a wet scrubber. Performance test data 
for the calciner are included in the docket. A fourth source operates 
six calciners. The calciners are similar in their design and emissions 
controls. Performance test data for those six are summarized in the 
TSD. Although speciation factors for HAP metals were available for the 
fourth source, the enforceable permit limits were for particulate 
matter. Given that the controls are the same for the best five units, 
the MACT floor level of control is based upon the use of wet scrubbers. 
The best performing calciners are permitted in a process rate format 
which allows the emissions rate to vary as function of process feed 
rate. For this class of sources, performance data show actual emissions 
to be well below permitted levels. The Agency has concluded that 
analysis of test data would best characterize the level of control 
being achieved in practice. Review of test data indicates that an 
emission limit equivalent to 0.06 grains of particulate matter per dry 
standard cubic foot (gr/dscf) is now being achieved by all calciners 
for which the Agency has data. This level of control was selected as 
the MACT floor for existing sources. The highest test data point for 
the calciners constituting the MACT floor was 0.058 gr/dscf. The Agency 
reviewed health impacts modelling provided by the fourth source and 
concluded that an ample margin of safety is provided at the MACT floor 
and that a more stringent standard for existing sources is not 
indicated. Thus, an emissions limit equivalent to the MACT floor is 
being proposed for existing calciners.
    Emissions test data for the best performing calciner indicated that 
it could meet a somewhat lower emission limit and that this could be 
considered the best controlled source for establishing new source MACT. 
The data showed that a similar new source could achieve an emission 
limit of 0.04 grains per dry standard cubic foot. This level of control 
is consistent with that which the Agency selected as best demonstrated 
technology for similar sources in the NSPS for calciners and dryers in 
the mineral industries (40 CFR Part 60, Subpart UUU). That standard was 
promulgated on September 28, 1992 in 57 FR 44503. Thus, the Agency is 
proposing 0.040 grains per dry standard cubic foot as MACT for new 
calciners located at phosphoric acid manufacturing plants.
    PPA Plants. Two sources in the United States manufacture PPA 
through the use of solvent extraction to further refine WPPA. One plant 
uses the HAP compound MIBK as a solvent. This results in permitted 
losses of MIBK which total approximately 29 tons per year. The second 
plant uses a different solvent and a different process from which no 
HAPs are emitted. The Act does not provide clear guidance on the 
establishment of MACT when less than five sources are present for floor 
analysis. In this instance, the following facts were considered. The 
two process designs are distinctly different. The owners of the second 
plant have patented their process and it is not readily available for 
licensing by competitors. The PPA produced by the source using MIBK is 
used in applications which differ in their requirements from the PPA 
produced by the competing source. Information provided by the owners of 
the plant using MIBK included information showing that reconstructing 
their plant to use a non-HAP solvent would result in a control cost of 
$800,000 per ton of MIBK reduced. This would clearly exceed the value 
of any environmental benefits to be derived. Thus, the Agency elected 
to set an emissions limit for MIBK based upon a MACT analysis of the 
one plant which uses that compound.
    The initial permit for the PPA plant in question allows the source 
to emit 19 tons of MIBK per year from the operation of the plant 
itself. That amount was determined by engineering calculations to 
predict the performance of the emissions controls installed at the 
plant. Information provided by the operator shows an estimated 9.9 tons 
per year of MIBK in a process waste stream being emitted from an 
adjoining fertilizer plant. The combined total of 28.9 tons of MIBK is 
equivalent to 0.16864 pounds of MIBK per ton of P2O5 fed to 
the process. Information listing historical purchases of makeup MIBK 
provided by the operators indicates that emissions may have exceeded 
that rate on several occasions. Additional information from the source 
shows that several changes to the process have been made to increase 
production. Insufficient information was provided to allow an analysis 
of how the process changes are affecting emissions. Likewise, no 
information has been provided to show what options have or could have 
been pursued to maintain the permitted emissions levels. Absent any 
basis for determining that the permitted limits are inconsistent with 
the emission controls installed at the plant, the Agency has elected to 
use the approach consistently applied to other phosphoric acid 
manufacturing processes during this rulemaking and to base MACT upon 
permitted emissions of MIBK. The MACT limit is proposed as 0.16864 
pounds of MIBK per ton of P2O5  fed to the process. The 
Agency specifically invites public comment upon this proposed action. 
Any comments advocating a different standard for emissions of MIBK from 
PPA plants should be accompanied and supported by data and information 
that clearly support the commenter's position.

[[Page 68441]]

D. Selection of Test Methods

    Included in the proposed rules are methods for determining initial 
compliance as well as monitoring, recordkeeping, and reporting 
requirements. All of these components are necessary to ensure that 
sources will comply with the standards both initially and over time. 
The Agency has made every effort to simplify the requirements in the 
rule. The Agency has also attempted to maintain consistency with 
existing regulations by either incorporating text from existing 
regulations or cross-referencing such regulations. Under the proposed 
rules, total fluoride would serve as a surrogate for HF and particulate 
matter would serve as a surrogate measure for HAP metals. So, for those 
standards which would limit emissions of total fluorides or particulate 
matter, the approaches to testing and monitoring in the corresponding 
NSPS would be adopted as closely as possible. That is, initial 
compliance would be determined by a performance test employing Agency 
Test Method 13 A or B for total fluorides or Method 5 for particulate 
matter. The owner or operator could also use other alternative test 
methods subject to approval by the Administrator. The proposed 
standards would require that sources continuously record and maintain 
control device pressure drop and liquid flow rate parameters within 
plus or minus ten percent of the values established during performance 
testing. Those values would have to be determined concurrently with 
initial performance testing. The values of the operating parameters 
would be based upon the average values recorded during three one-hour 
test runs. This approach to monitoring control device operating 
parameters and an alternative requested by industry are discussed in 
the monitoring requirements section of this preamble.
    During the development of the proposed NESHAP, two concerns were 
raised by industry about testing for fluoride emissions. First, the 
industry suggested that Method 13 B could be simplified. In response, 
the Agency is proposing to simplify Method 13 B for this source 
category by eliminating the fusion and distillation steps in the sample 
preparation. The fusion step is intended to make all fluorides water 
soluble. For these source categories, preliminary information indicates 
that all fluorides are water soluble. The distillation step is intended 
to eliminate analytical interferences. Industry has submitted data that 
indicates that the distillation step is unneeded for these source 
categories. At this time the Agency is reviewing data to verify that 
the requested changes in the test method are reasonable. The changes 
would not apply to other categories of sources.
    The second concern raised was that of how to test uncontrolled GTSP 
storage buildings using method 13 A or B. Uncontrolled buildings do not 
have a stack or a single discharge point. Section 63.7 of the general 
provisions provides that sources may develop site-specific test plans.
    The Agency is working with the affected sources and their 
respective permitting agencies through this site- specific test plan 
process to develop a consistent methodology for the purpose of 
determining whether the sources can achieve the emission limits of the 
proposed standards without add-on controls.

E. Selection of Monitoring Requirements

    The proposed standards would require that sources continuously 
monitor and maintain control device operating parameters within plus or 
minus ten percent of the values established during performance testing. 
Since control of particulate matter is impaired by a lessening of 
pressure drop or liquid flow rate, decreases in these parameters 
indicate a decline in emissions control efficiency. For HF, as 
determined by total fluoride, the opposite effect can occur. Removal of 
fluorides by wet scrubbers is enhanced by increased residence time in 
the control device. So, it is appropriate that an upper bound to 
pressure drop should be included as a means of maintaining residence 
time at a value similar to that obtained during the performance test. 
Similar to the NSPS, the proposed NESHAP would require monitoring of 
process feed rate.
    During development of the proposed NESHAP, industry representatives 
expressed some concern over EPA's intention to define scrubber 
monitoring parameter exceedances in excess of plus or minus ten percent 
of the values established during the most recent performance test as 
violations. That concern centered upon the possibility that those 
values could change as a result of equipment or process variables which 
would not necessarily result in noncompliance with the numerical limits 
of the standards. They suggested that Agency should allow a grace 
period for re-testing to determine compliance with the numerical limits 
of the standard. In particular, the inclusion of the upper bound was 
questioned. The Agency's response is that the upper limit is 
appropriate because higher pressure drops could indicate that emissions 
controls were suffering from a reduction in residence time associated 
with higher pressure drops or process upsets and the Agency has elected 
to keep the upper band for parameter excursions because of enforcement 
concerns. To allay the concerns of industry, the Agency is including in 
the proposed regulation language which provides a grace period for re-
testing under the conditions measured during the exceedance to 
determine compliance. Upon considering that some sources at relatively 
remote locations need time to arrange for services of outside test 
crews, the proposed rule would allow sources thirty days to re-test and 
demonstrate compliance with the numerical emissions limits. If a source 
is re-tested within that time period and passes the required test, the 
exceedances of the parameter limits would not be considered violations 
of the Act.
    Some industry representatives recommended defining the acceptable 
range of operational parameters on the basis of the ranges resulting 
from previous or specially-conducted successful performance tests. 
Initially, the Agency considered this approach and concluded that to 
require extensive testing to develop operational ranges during 
performance testing could be construed as burdensome. So, the Agency 
chose the approach first described in this section as a requirement. In 
addition, the proposed regulations would allow use of the approach 
requested by industry, with its attendant costs, as an alternative 
which sources could choose to employ at their discretion. In 
particular, the alternative provides flexibility for sources to 
establish operational ranges for control device parameters on the basis 
of data derived from multiple performance tests. Operating ranges could 
based upon values recorded during previous successful performance tests 
or upon the results of new performance testing conducted specifically 
for the purpose of establishing operating ranges. Sources would be 
required to certify that the control devices and processes had not been 
modified subsequent to the testing upon which the data used to 
establish the operating ranges were obtained. Following the approval by 
the permitting authority of operating ranges for the affected source, 
any three hour averages of the values of total pressure drop or flow 
rate of the scrubbing liquid in exceedance of the approved operating 
ranges would constitute violations of applicable emission limits.
    For PPA plants, compliance would be determined by inventory records 
documenting the amounts of MIBK

[[Page 68442]]

added to the process as makeup for routine losses from the system. In 
addition, the source would be required to maintain records of 
maintenance activities which would include estimates of MIBK losses. 
The source would be required to document in its inventory any losses 
from nonroutine equipment failures or malfunctions. On a continuing 
basis, the source would be required to monitor and record the MIBK 
content of raffinate, gas chiller temperature and cooling tower losses. 
Recordkeeping and reporting would be subject to the General Provisions 
to 40 CFR Part 63.

F. Selection of Notification, Reporting, and Recordkeeping Requirements

    All requirements of the General Provisions apply under the proposed 
rule. The General Provisions include requirements for notifications; 
reports on performance test results; semiannual excess emissions 
reports; and startup, shutdown, and malfunction plans and reports. 
Startups, shutdowns, and malfunctions of production lines can occur in 
this industry. The development and implementation of the plan will aid 
in reducing emissions from these events and in reducing malfunctions. A 
semiannual report to EPA is required only in the event a reportable 
event occurs and the steps in the plan were not followed. Semiannual 
excess emission reports are required to ensure that the permitting 
authority is aware of any potential operating or compliance problems at 
the source.
    The proposed rule requires that minimum information and data be 
maintained in a file available for inspection at the site. Records of 
control device operational parameters, process feed rate, MIBK addition 
to PPA plants and MIBK concentrations at specified points would be 
required to ensure that MACT-level controls are in place and properly 
operated and maintained.

G. Solicitation of Comments

    The EPA seeks full public participation in arriving at its final 
decisions and encourages comments on all aspects of this proposal from 
all interested parties. Full supporting data and detailed analyses 
should be submitted with comments to allow EPA to make maximum use of 
the comments. All comments should be directed to the Air and Radiation 
Docket and Information Center, Docket No. A-95-33 (see ADDRESSES). 
Comments on this notice must be submitted on or before the date 
specified in DATES.
    Commentors wishing to submit proprietary information for 
consideration should clearly distinguish such information from other 
comments and clearly label it ``Confidential Business Information'' 
(CBI). Submissions containing such proprietary information should be 
sent directly to the Emission Standards Division CBI Office, U.S. 
Environmental Protection Agency (MD-13), Research Triangle Park, North 
Carolina 27711, with a copy of the cover letter directed to the contact 
person listed above. Confidential business information should not be 
sent to the public docket. Information covered by such a claim of 
confidentiality will be disclosed by EPA only to the extent allowed and 
by the procedures set forth in 40 CFR part 2. If no claim of 
confidentiality accompanies the submission when it is received by EPA, 
it may be made available to the public without further notice to the 
commentor.

V. Impacts of Proposed Standards

A. Applicability

    Currently, 21 phosphoric acid manufacturing and phosphate 
fertilizers production complexes, owned by 15 companies, are located in 
seven States. The EPA estimates that five of these plants would need to 
install better controls on at least one process each to reduce 
emissions. All plants in the industry would be subject to the proposed 
standards unless the plant owner or operator demonstrates that the 
facility is not a major source. The Agency expects that six of the 21 
phosphate fertilizers production complexes will be demonstrated to be 
non-major sources.

B. Air Quality Impacts

    Nationwide HAP emissions from phosphoric acid manufacturing and 
phosphate fertilizers production complexes are estimated to be up to 
550 Mg/yr (605 tpy) of HF and other HAP at the current level of 
control. Implementation of the proposed NESHAP would reduce HF 
emissions by 315 Mg/yr (345 tpy) from currently permitted levels. The 
corresponding reduction in total fluorides would be 940 Mg/yr (1035 
tpy). This would equate to 1570 Mg (1725 tons) of HF and 4700 Mg (5175 
tons) of total fluoride over the first five years of the proposed 
standards. Since the PPA plant emitting MIBK and calciners emitting HAP 
metals in the form of particulates would meet the NESHAP in their 
current configurations, no additional emissions reductions would be 
gained from those operations. The proposed NESHAP would ensure that the 
currently installed control systems would be properly operated and 
maintained. Additional information on emissions and emission reductions 
is included in the TSD.

C. Water Impacts

    As a result of NESHAP, five plants would install five to six low 
energy scrubbers using recycled pond water as the scrubbing liquid 
would result from NESHAP. Most, if not all, new scrubbers would employ 
cooling pond water as the scrubbing fluid and return the scrubber 
discharge to the pond for recycle to the process. The impacts of this 
would therefore be minimal.

D. Solid Waste Impacts

    Solid waste impacts would be minimal.

E. Energy Impacts

    A total of five to six low energy scrubbers would result from 
NESHAP. Increased power for the scrubbers was estimated to cause an 
additional annual power consumption of twenty million kilowatt hours.

F. Nonair Environmental and Health Impacts

    Reducing HAPs and ambient pollutant levels may help lower 
occupational exposure levels.

G. Cost Impacts

    The proposed rule would affect phosphoric acid manufacturing and 
phosphate fertilizers production facilities that are major sources or 
that are located at major sources. The Agency projects that six process 
lines at existing source complexes would install new control systems. 
The Agency estimated that five additional sources would be expected to 
employ better operation and maintenance practices to meet the 
standards. Based upon availability of surplus production capacity and 
recent market trends, the Agency projects that no new facilities will 
be constructed within the next five years. For the five plants expected 
to add new air pollution control scrubbers to meet the proposed NESHAP, 
the capital cost of new control devices is estimated to be $1,401,561. 
Estimated annualized capital, operation, and maintenance costs of new 
scrubbers are estimated to total $847,851. The annual costs for the 
plants expected to implement improved operation and maintenance are 
estimated to be $14,400. Thus, the total annualized costs of the 
standards would be $862,251 nationwide.

H. Economic Impacts

    Prices are expected to increase in each regional market by the per-
unit-cost

[[Page 68443]]

increase for the marginal firm. Because neither the exact regional 
structure, nor which firm is the high cost producer within the region, 
is known, a range of prices changes has been estimated. For the lower 
estimate, one national market is assumed for each good. The production 
weighted average cost increase is assumed to be the expected cost 
increase for the marginal firm and is used for the price increase. The 
higher estimate has been developed by using the highest cost increase 
among the facilities as the cost increase for the marginal firm. This 
makes the highest cost increase the price increase for the national 
market. Even the highest estimate for the product (MAP/DAP) with the 
highest cost increase would be a price increase of less than one third 
of one percent.
    Although demand elasticity estimates are not available, the lack of 
close substitutes, the small cost share of fertilizers in final 
agricultural products, and the expected low elasticity for the 
production of food lead to the expectation of an inelastic demand. 
Since elasticity of demand would be expected to be less than one, 
percentage quantity adjustments would be expected to be smaller than 
the percentage price changes discussed above.
    Detailed plant information needed for plant closure analysis is not 
available, but, plant closure as a result of the costs of this 
regulation would be unlikely. The highest estimate for market quantity 
adjustment is less than three percent of the production of the smallest 
affected facility for each of the three markets. If there were to be no 
market price increase, the cost increase as a percentage of sales would 
always be less than two-fifths of a percent. While closure due to the 
regulation would be unlikely, a facility planning to close in the 
absence of the regulation could close earlier because of the 
regulation. The effect of this regulation would be expected to be 
minimal on both small businesses and the industry as a whole.

VI. Administrative Requirements

A. Docket

    The docket is an organized and complete file of all the information 
considered by EPA in the development of this rulemaking. The docket is 
a dynamic file, because material is added throughout the rulemaking 
development. The docketing system is intended to allow members of the 
public and industries involved to readily identify and locate documents 
so that they can effectively participate in the rulemaking process. 
Along with the proposed and promulgated standards and their preambles, 
the contents of the docket will serve as the record in the case of 
judicial review. [See section 307(d)(7)(A) of the Act.]

B. Public Hearing

    A public hearing will be held, if requested, to discuss the 
proposed standards in accordance with section 307(d)(5) of the Act. 
Persons wishing to make oral presentations on the proposed standards 
should contact EPA (see ADDRESSES). If a public hearing is requested 
and held, EPA will ask clarifying questions during the oral 
presentation but will not respond to the presentations or comments. To 
provide an opportunity for all who may wish to speak, oral 
presentations will be limited to 15 minutes each. Any member of the 
public may file a written statement on or before February 25, 1997. 
Written statements should be addressed to the Air and Radiation Docket 
and Information Center (see ADDRESSES), and refer to Docket No. A-95-
33. Written statements and supporting information will be considered 
with equivalent weight as any oral statement and supporting information 
subsequently presented at a public hearing, if held. A verbatim 
transcript of the hearing and written statements will be placed in the 
docket and be available for public inspection and copying, or mailed 
upon request, at the Air and Radiation Docket and Information Center 
(see ADDRESSES).

C. Executive Order 12866

    Under Executive Order 12866 [58 FR 51735 (October 4, 1993)], the 
Agency must determine whether the regulatory action is ``significant'' 
and therefore subject to review by the Office of Management and Budget 
(OMB), and the requirements of the Executive Order. The Order defines 
``significant regulatory action'' as one that is likely to result in a 
rule that may: (1) have an annual effect on the economy of $100 million 
or more or adversely affect in a material way the economy, a sector of 
the economy, productivity, competition, jobs, the environment, public 
health or safety, or State, local, or tribal governments or 
communities; (2) create a serious inconsistency or otherwise interfere 
with an action taken or planned by another agency; (3) materially alter 
the budgetary impact of entitlement, grants, user fees, or loan 
programs, or the rights and obligation of recipients thereof; or (4) 
raise novel legal or policy issues arising out of legal mandates, the 
President's priorities, or the principles set forth in the Executive 
Order.
    Pursuant to the terms of Executive Order 12866, the Agency has 
determined that this rule is not ``significant'' because none of the 
listed criteria apply to this action. Consequently, this action was not 
submitted to OMB for review under Executive Order 12866.

D. Enhancing the Intergovernmental Partnership Under Executive Order 
12875

    In compliance with Executive Order 12875, the Agency involved 
State,local and Federal governments in the development of this rule. 
These governments are not directly impacted by the rule; i.e. they are 
not required to purchase control systems to meet the requirements of 
the rule. However, they will be required to implement the rule; e.g. 
incorporate the rule into permits and enforce the rule. They will 
collect permit fees which will be used to offset the resource burden of 
implementing the rule. One representative of a State environmental 
agency has been a member of the EPA work group developing the rule. In 
addition, the Agency has contacted the staffs of State air pollution 
control agencies to exchange information during development of the 
rule. The comments and suggestions of the State agency staffs have been 
carefully considered in the rule development. In addition, all States 
are encouraged to comment on this proposed rule during the public 
comment period and the Agency intends to fully consider these comments 
in the final rulemaking.

E. Unfunded Mandates Reform Act

    Section 202 of the Unfunded Mandates Reform Act of 1995 (``Unfunded 
Mandates Act''), signed into law on March 22, 1995 (109 Stat. 48), 
requires that the Agency prepare a budgetary impact statement before 
promulgating a rule that includes a Federal mandate that may result in 
expenditure by State, local, and tribal governments, in aggregate, or 
by the private sector, of $100 million or more in any one year. Section 
203 requires the Agency to establish a plan for obtaining input from 
and informing, educating, and advising any small governments that may 
be significantly or uniquely affected by the rule.
    Under section 205 of the Unfunded Mandates Act, the Agency must 
identify and consider a reasonable number of regulatory alternatives 
before promulgating a rule for which a budgetary impact statement must 
be prepared. The Agency must select from those alternatives the least 
costly, most cost-effective, or least burdensome alternative for State, 
local, and tribal governments and the private sector that

[[Page 68444]]

achieves the objectives of the rule, unless the Agency explains why 
this alternative is not selected or unless the selection of this 
alternative is inconsistent with law.
    Because this proposed rule, if promulgated, is estimated to result 
in the expenditure by State, local, and tribal governments or the 
private sector of less than $100 million in any one year, the Agency 
has not prepared a budgetary impact statement or specifically addressed 
the selection of the least costly, most cost-effective, or least 
burdensome alternative. Because small governments will not be 
significantly or uniquely affected by this rule, the Agency is not 
required to develop a plan with regard to small governments. Therefore, 
the requirements of the Unfunded Mandates Act do not apply to this 
action.

F. Regulatory Flexibility Act

    Under the Regulatory Flexibility Act of 1980, 5 U.S.C. 601 et seq., 
Federal agencies are required to assess the economic impact of Federal 
regulations on small entities. The Regulatory Flexibility Act specifies 
that Federal agencies must prepare an initial Regulatory Flexibility 
Analysis (RFA) if a proposed regulation will have a significant 
economic impact on a substantial number of small entities.
    The Agency has found that two of the twenty one firms that 
potentially would be subject to the proposed standards are small firms. 
Of the two, one is an area source which would not be covered by the 
standards. The second source would be major and subject to the 
requirements of the standards. Information available to the Agency 
shows that the second source is able to achieve the control levels of 
the proposed NESHAP using existing equipment. The testing, monitoring, 
recordkeeping and reporting requirements are essentially identical to 
current requirements and, thus, would cause little or no change in 
these burdens. Therefore, given that only one small entity would see 
only a minimal change from its current requirements, the Agency 
certifies that the proposed rulemaking will not impact a substantial 
number of small entities and that any impacts would be non-significant.

G. Paperwork Reduction Act

    The information collection requirements in this proposed rule have 
been submitted for approval to the Office of Management and Budget 
(OMB) under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. An 
Information Collection Request (ICR) document has been prepared by EPA 
(ICR No. 1790.01) and a copy may be obtained from Sandy Farmer, OPPE 
Regulatory Information Division; U.S. Environmental Protection Agency 
(2137); 401 M St., S.W.; Washington, DC 20460 or by calling (202) 260-
2740.
    The information to be collected includes the results of performance 
testing to be conducted to demonstrate initial compliance with the 
emissions limits in the proposed rules. At the time that performance 
testing would be performed, sources would be required to measure and 
record operating parameters for the processes and control devices. 
Following the performance testing, sources would be required under 
authority of the Act to monitor and record operating parameters to 
assure that they were maintained within approved ranges, based upon 
values determined during the initial tests. The purpose of the 
monitoring and recordkeeping requirements would be to provide 
implementing agencies information to assure that MACT was being 
implemented on an ongoing basis.
    The Agency estimated the projected cost and hour burden of the 
proposed standards. The average annual reporting burden was estimated 
to be 132 hours per response. There would be fifteen likely respondents 
and reports would required twice a year. The total burden would equate 
to 3790 hours per year nationwide and the corresponding cost was 
estimated to be $121,773 per year. The total capital cost of the 
monitoring devices was estimated to be $564, 200 of which the major 
cost would be for the installation of sensors to measure and record the 
flow of scrubbing liquid to the control devices. The annualized cost of 
that capital would be $53,200 per year and the operation and 
maintenance of the monitoring equipment was estimated as $13,300 per 
year. Thus, the total annualized capital and operation and maintenance 
costs were estimated to be $66,500 per year. Burden means the total 
time, effort, or financial resources expended by persons to generate, 
maintain, retain, or disclose or provide information to or for a 
Federal agency. This includes the time needed to review instructions; 
develop, acquire, install, and utilize technology and systems for the 
purposes of collecting, validating, and verifying information, 
processing and maintaining information, and disclosing and providing 
information; adjust the existing ways to comply with any previously 
applicable instructions and requirements; train personnel to be able to 
respond to a collection of information; search data sources; complete 
and review the collection of information; and transmit or otherwise 
disclose the information.
    An Agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulations are listed in 40 CFR Part 9 and 48 CFR Chapter 15.
    Comments are requested on the Agency's need for this information, 
the accuracy of the provided burden estimates, and any suggested 
methods for minimizing respondent burden, including through the use of 
automated collection techniques. Send comments on the ICR to the 
Director, OPPE Regulatory Information Division; U.S. Environmental 
Protection Agency (2137); 401 M St., S.W.; Washington, DC 20460; and to 
the Office of Information and Regulatory Affairs, Office of Management 
and Budget, 725 17th St., N.W., Washington, DC 20503, marked 
``Attention: Desk Officer for EPA.'' Include the ICR number in any 
correspondence. Since OMB is required to make a decision concerning the 
ICR between 30 and 60 days after December 27, 1996, a comment to OMB is 
best assured of having its full effect if OMB receives it by January 
27, 1997. The final rule will respond to any OMB or public comments on 
the information collection requirements contained in this proposal.

H. Clean Air Act

    In accordance with section 117 of the Act, publication of this 
proposal was preceded by consultation with appropriate advisory 
committees, independent experts, and Federal departments and agencies. 
This regulation will be reviewed 8 years from the date of promulgation. 
This review will include an assessment of such factors as evaluation of 
the residual health risks, any overlap with other programs, the 
existence of alternative methods, enforceability, improvements in 
emission control technology and health data, and the recordkeeping and 
reporting requirements.

I. Pollution Prevention Act

    During the development of the standards, the Agency explored 
opportunities to eliminate or reduce emissions through the application 
of new processes or work practices. As previously discussed, at the 
outset the Agency explored options for reduction of cooling pond 
emissions of HF. Among the possibilities was a recently patented 
process which offers the promise of eliminating the ponds altogether 
while at the same time

[[Page 68445]]

recovery HF for sale to outside parties. At this time that process has 
not yet been commercially demonstrated.
    The other opportunity for prevention of pollution arose when the 
Agency learned of the piping of air pollution control scrubber effluent 
to cooling towers, where the HF content was being stripped and emitted 
to the atmosphere. As previously discussed, the proposed NESHAP would 
expressly prohibit that practice.

List of Subjects in 40 CFR Part 63

    Environmental protection, Air pollution control, Intergovernmental 
relations, Reporting and recordkeeping requirements, Phosphoric acid 
manufacturing, and Phosphate fertilizers production.

    Dated: November 21, 1996.
Carol M. Browner,
Administrator.
    For the reasons set out in the preamble, it is proposed that part 
63 of title 40, chapter I, of the Code of Federal Regulations be 
amended as follows:

PART 63--NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS 
FOR SOURCE CATEGORIES

    1. The authority for part 63 continues to read as follows:

    Authority: 42 U.S.C. 7401 et seq.

    2. Part 63 is amended by adding subpart AA consisting of 
Secs. 63.600 through 63.610 to read as follows:
Subpart AA--National Emission Standards for Hazardous Air Pollutants 
From Phosphoric Acid Manufacturing Plants
Sec.
63.600  Applicability.
63.601  Definitions.
63.602  Standards for existing sources.
63.603  Standards for new sources.
63.604  Monitoring requirements.
63.605  Performance tests and compliance provisions.
63.606  Notification requirements.
63.607  Recordkeeping requirements.
63.608  Reporting requirements.
63.609  Compliance dates.
63.610  Exemption from new source performance standards.

Subpart AA--National Emission Standards for Hazardous Air 
Pollutants From Phosphoric Acid Manufacturing Plants


Sec. 63.600  Applicability.

    (a) Except as provided in paragraph (c) of this section, the 
requirements of this subpart apply to the owner or operator of each new 
or existing phosphoric acid manufacturing plant.
    (b) The requirements of this subpart apply to emissions of 
hazardous air pollutants (HAPs) emitted from the following affected 
sources at a new or existing phosphoric acid manufacturing plant:
    (1) Each wet-process phosphoric acid plant. The requirements of 
this subpart apply to the following emission points which are 
components of a wet-process phosphoric acid plant: reactors, filters, 
evaporators, and hot wells.
    (2) Each evaporative cooling tower at a phosphoric acid 
manufacturing plant.
    (3) Each phosphate rock dryer located at a phosphoric acid 
manufacturing plant.
    (4) Each phosphate rock calciner located at a phosphoric acid 
manufacturing plant.
    (5) Each superphosphoric acid plant. The requirements of this 
subpart apply to the following emission points which are components of 
a superphosphoric acid plant: evaporators, hot wells, acid sumps, and 
cooling tanks; and
    (6) Each purified acid plant. The requirements of this subpart 
apply to the following emission points which are components of a 
purified phosphoric acid plant: solvent extraction process equipment, 
solvent stripping and recovery equipment, seal tanks, carbon treatment 
equipment, cooling towers, storage tanks, pumps and process piping.
    (c) The requirements of this subpart do not apply to the owner or 
operator of a new or existing phosphoric acid manufacturing plant for 
which the owner or operator demonstrates, to the satisfaction of the 
Administrator, that the facility is not a major source as defined in 
Sec. 63.2.


Sec. 63.601  Definitions.

    Terms used in this subpart are defined in the Clean Air Act, in 
Sec. 63.2, or in this section as follows:
    Equivalent P2O5 feed means the quantity of phosphorus, 
expressed as phosphorous pentoxide, fed to the process.
    Evaporative cooling tower means an open water recirculating device 
that uses fans or natural draft to draw or force ambient air through 
the device to remove heat from process water by direct contact.
    HAP metals mean those chemicals and their compounds (in particulate 
or volatile form) that are included on the list of hazardous air 
pollutants in section 112 of the Clean Air Act. HAP metals include, but 
are not limited to: antimony, arsenic, beryllium, cadmium, chromium, 
lead, manganese, nickel, and selenium expressed as particulate matter 
as measured by the methods and procedures in this subpart or an 
approved alternative method. For the purposes of this subpart, HAP 
metals are expressed as particulate matter as measured by 40 CFR Part 
60, Appendix A, Method 5.
    Phosphate rock calciner means the equipment used to remove moisture 
and organic matter from phosphate rock through direct or indirect 
heating.
    Phosphate rock dryer means the equipment used to reduce the 
moisture content of phosphate rock through direct or indirect heating.
    Phosphate rock feed means all material entering any phosphate rock 
dryer or phosphate rock calciner including moisture and extraneous 
material as well as the following ore materials: fluorapatite, 
hydroxylapatite, chlorapatite, and carbonateapatite.
    Purified phosphoric acid plant means any facility which 
concentrates wet-process phosphoric acid to 58 percent or greater 
P2O5 content by weight and which uses solvent extraction to 
separate impurities from the product acid for the purposes of rendering 
that product suitable for industrial, manufacturing or food grade uses.
    Superphosphoric acid plant means any facility which concentrates 
wet-process phosphoric acid to 66 percent or greater P2O5 
content by weight.
    Total fluorides means elemental fluorine and all fluoride 
compounds, including the HAP hydrogen fluoride, as measured by 
reference methods specified in 40 CFR Part 60, Appendix A , Method 13 A 
or B, or by equivalent or alternative methods approved by the 
Administrator pursuant to Sec. 63.7(f).
    Wet process phosphoric acid plant means any facility manufacturing 
phosphoric acid by reacting phosphate rock and acid.


Sec. 63.602  Standards for existing sources.

    (a) Wet process phosphoric acid plant. On and after the date on 
which the performance test required to be conducted by Secs. 63.7 and 
63.605 is completed, no owner or operator subject to the provisions of 
this subpart shall cause to be discharged into the atmosphere from any 
affected source any gases which contain total fluorides in excess of 
10.0 gram/metric ton of equivalent P2O5 feed (0.020 lb/ton).
    (b) Superphosphoric acid plant. (1) On and after the date on which 
the performance test required to be conducted by Secs. 63.7 and 63.605 
is completed, no owner or operator subject to the provisions of this 
subpart shall cause to be discharged into the atmosphere from any 
affected source any gases which contain total fluorides in excess of 
5.0 gram/metric ton of equivalent P2O5 feed (0.010 lb/ton).

[[Page 68446]]

    (2) Notwithstanding paragraph (b)(1) of this section, on and after 
the date on which the performance test required to be conducted by 
Secs. 63.7 and 63.605 is completed, each submerged combustion process 
superphosphoric acid plant at the Arcadian Fertilizers facility in 
Geismar, Louisiana shall not cause to be discharged into the atmosphere 
any gases which contain total fluorides in excess of 100.0 gram/metric 
ton of equivalent P2O5 feed (0.20 lb/ton).
    (c) Phosphate rock dryer. On or after the date on which the 
performance test required to be conducted by Secs. 63.7 and 63.605 is 
completed, no owner or operator subject to the provisions of this 
subpart shall cause to be discharged into the atmosphere from any 
affected source any gases which contain particulate matter in excess of 
0.10750 kilogram/metric ton of phosphate rock feed (0.2150 lb/ton).
    (d) Phosphate rock calciner. On or after the date on which the 
performance test required to be conducted by Secs. 63.7 and 63.605 is 
completed, no owner or operator subject to the provisions of this 
subpart shall cause to be discharged into the atmosphere from any 
affected source any gases which contain particulate matter in excess of 
0.138 gram per dry standard cubic meter (g/dscm) [0.060 grain per dry 
standard cubic foot (gr/dscf)].
    (e) Evaporative cooling tower. No owner or operator shall introduce 
into any evaporative cooling tower any liquid effluent from any wet 
scrubbing device installed to control emissions from process equipment.
    (f) Purified phosphoric acid plant. No owner or operator subject to 
the provisions of this subpart shall cause to be discharged into the 
atmosphere from any affected source any gases which contain methyl 
isobutyl ketone in excess of 84.320 gram/metric ton of equivalent 
P2O5 feed (0.16864 lb/ton). Compliance shall be determined as 
a monthly average based upon records of the addition of methyl isobutyl 
ketone to the process as required in Sec. 63.605(f).


Sec. 63.603  Standards for new sources.

    (a) Wet process phosphoric acid plant. On and after the date on 
which the performance test required to be conducted by Secs. 63.7 and 
63.605 is completed, no owner or operator subject to the provisions of 
this subpart shall cause to be discharged into the atmosphere from any 
affected source any gases which contain total fluorides in excess of 
6.750 gram/metric ton of equivalent P2O5 feed (0.01350 lb/
ton).
    (b) Superphosphoric acid plant. On and after the date on which the 
performance test required to be conducted by Secs. 63.7 and 63.605 is 
completed, no owner or operator subject to the provisions of this 
subpart shall cause to be discharged into the atmosphere from any 
affected source any gases which contain total fluorides in excess of 
4.35 gram/metric ton of equivalent P2O5 feed (0.00870 lb/
ton).
    (c) Phosphate rock dryer. On or after the date on which the 
performance test required to be conducted by Secs. 63.7 and 63.605 is 
completed, no owner or operator subject to the provisions of this 
subpart shall cause to be discharged into the atmosphere from any 
affected source any gases which contain particulate matter in excess of 
0.030 kilogram/metric ton per megagram of phosphate rock feed (0.060 
lb/ton).
    (d) Phosphate rock calciner. On or after the date on which the 
performance test required to be conducted by Secs. 63.7 and 63.605 is 
completed, no owner or operator subject to the provisions of this 
subpart shall cause to be discharged into the atmosphere from any 
affected source any gases which contain particulate matter in excess of 
0.0920 gram per dry standard cubic meter (g/dscm) [0.040 grain per dry 
standard cubic foot (gr/dscf)].
    (e) Evaporative cooling tower. No owner or operator shall introduce 
into any evaporative cooling tower any liquids containing the effluent 
from any air pollution control device.
    (f) Purified phosphoric acid plant. No owner or operator subject to 
the provisions of this subpart shall cause to be discharged into the 
atmosphere from any affected source any gases which contain methyl 
isobutyl ketone in excess of 84.320 gram/metric ton of equivalent 
P2O5 feed (0.16864 lb/ton). Compliance shall be determined as 
a monthly average based upon records of the addition of methyl isobutyl 
ketone to the process.


Sec. 63.604  Monitoring requirements.

    (a) Each owner or operator of a new or existing wet-process 
phosphoric acid plant, superphosphoric acid plant, phosphate rock 
dryer, phosphate rock calciner, or purified phosphoric acid plant 
subject to the provisions of this subpart shall install, calibrate, 
maintain, and operate a monitoring system which can be used to 
determine and permanently record the mass flow of phosphorus-bearing 
feed material to the process. The monitoring system shall have an 
accuracy of 5 percent over its operating range.
    (b) Each owner or operator of a new or existing wet-process 
phosphoric acid plant, superphosphoric acid plant, phosphate rock 
calciner, or purified phosphoric acid plant subject to the provisions 
of this subpart shall maintain a daily record of equivalent 
P2O5 feed by first determining the total mass rate in metric 
ton/hour of phosphorus bearing feed using a monitoring system for 
measuring mass flowrate which meets the requirements of paragraph (a) 
of this section and then by proceeding according to Sec. 63.605(c)(3).
    (c) Each owner or operator of a new or existing wet-process 
phosphoric acid plant, superphosphoric acid plant, phosphate rock dryer 
or phosphate rock calciner using a wet scrubbing emission control 
system shall install, calibrate, maintain, and operate the following 
monitoring systems:
    (1) A monitoring system which continuously measures and permanently 
records the total pressure drop across each scrubber in the process 
scrubbing system. The monitoring system shall be certified by the 
manufacturer to have an accuracy of 5 percent over its 
operating range.
    (2) A monitoring system which continuously measures and permanently 
records the flow rate of the scrubbing liquid to each scrubber in the 
process scrubbing system. The monitoring system shall be certified by 
the manufacturer to have an accuracy of 5 percent over its 
operating range.
    (d) Any new or existing source subject to emissions limitations for 
total fluorides or particulate matter contained in this subpart shall 
comply with either paragraph (d) (1) or (2) of this section:
    (1) For a new or existing affected source, following the date on 
which the performance test required in Sec. 63.605 is completed, any 
three-hour average of the total pressure drop across the scrubber(s) or 
of the flow rate of the scrubbing liquid to the scrubber(s) in the 
process scrubbing system which exceeds  ten percent of the 
value determined as a requirement of Sec. 63.605(c)(4), (d)(4), or 
(e)(2) shall constitute a violation of the applicable emission limit 
contained in this subpart unless the affected source performs and 
passes a performance test as required in Sec. 63.605 within thirty days 
following the exceedance. Any owner or operator who intends to conduct 
a performance test pursuant to this paragraph shall notify the 
Administrator of that intention within one business day of the 
parameter exceedance. Any owner or operator conducting a performance 
test pursuant to this paragraph (d)(1) shall establish and maintain 
during that test the same operating conditions as were determined 
during the exceedance of the operating range.
    (2) The owner or operator of any new or existing affected source 
shall establish operating ranges for the total

[[Page 68447]]

pressure drop across or of the flow rate of the scrubbing liquid to 
each scrubber in the process scrubbing system for the purpose of 
assuring compliance with applicable emission limits required in this 
subpart. Operating ranges may be based upon values recorded during 
previous performance tests using the test methods required in this 
subpart and established in the manner required in Sec. 63.605 (c)(4), 
(d)(4), or (e)(2). As an alternative the owner or operator can base the 
operating ranges upon the results of performance tests conducted 
specifically for the purposes of this paragraph (d)(2) using the test 
methods required in this subpart and established in the manner required 
in Sec. 63.605(c)(4), (d)(4), or (e)(2). The source shall certify that 
the control devices and processes have not been modified subsequent to 
the testing upon which the data used to establish the operating ranges 
were obtained. Following the approval by the permitting authority of 
operating ranges for the affected source, any three hour average of the 
values of total pressure drop or flow rate of the scrubbing liquid 
which exceeds the approved operating ranges shall constitute a 
violation of the applicable emission limit contained in this subpart.
    (e) Each owner or operator of a new or existing purified phosphoric 
acid plant shall: (1) Install, calibrate, maintain, and operate a 
monitoring system which continuously measures and permanently records 
the stack gas exit temperature for each chiller stack. (2) Measure and 
record the concentration of methyl isobutyl ketone in each product acid 
stream and each raffinate stream once daily.
    (f) For any new or existing purified phosphoric acid plant, any of 
the following shall constitute a violation of this subpart:
    (1) A thirty day average of daily concentration measurements of 
methyl isobutyl ketone in excess of twenty parts per million for each 
stripped acid stream.
    (2) A thirty day average of daily concentration measurements of 
methyl isobutyl ketone in excess of thirty parts per million for each 
raffinate stream.
    (3) A daily average chiller stack exit gas stream temperature in 
excess of fifty degrees Fahrenheit.


Sec. 63.605  Performance tests and compliance provisions.

    (a) Each owner or operator of a new or existing phosphoric acid 
manufacturing plant shall conduct a performance test to demonstrate 
compliance with the applicable emission standard for each wet-process 
phosphoric acid plant, superphosphoric acid plant, phosphate rock 
dryer, and phosphate rock calciner. If the affected source has multiple 
control devices and/or emission points subject to the provisions of 
this subpart, those control devices and/or emission points shall be 
tested simultaneously. The owner or operator shall conduct the 
performance test according to the procedures in the General Provisions 
in subpart A of this part and in this section.
    (b) In conducting performance tests, each owner or operator of an 
affected source shall use as reference methods and procedures the test 
methods in 40 CFR Part 60, Appendix A, or other methods and procedures 
as specified in this section, except as provided in Sec. 63.7(f).
    (c) Each owner or operator of a new or existing wet-process 
phosphoric acid plant or superphosphoric acid plant shall determine 
compliance with the applicable total fluorides standards in Sec. 63.602 
or Sec. 63.603 as follows:
    (1) The emission rate (E) of total fluorides shall be computed for 
each run using the following equation:
[GRAPHIC] [TIFF OMITTED] TP27DE96.009

Where:

E=emission rate of total fluorides, g/metric ton (lb/ton) of 
equivalent P2O5 feed.
Csi=concentration of total fluorides from emission point ``i,'' 
mg/dscm (mg/dscf).
Qsdi=volumetric flow rate of effluent gas from emission point 
``i,'' dscm/hr (dscf/hr).
N=number of emission points associated with the affected facility.
P=equivalent P2O5 feed rate, metric ton/hr (ton/hr).
K=conversion factor, 1000 mg/g (453,600 mg/lb).

    (2) Method 13A or 13B (40 CFR part 60, appendix A) shall be used to 
determine the total fluorides concentration (Csi) and volumetric 
flow rate (Qsdi) of the effluent gas from each of the emission 
points. If Method 13 B is used, the fusion of the filtered material 
described in Section 7.3.1.2 and the distillation of suitable aliquots 
of containers 1 and 2, described in section 7.3.3 and 7.3.4. in Method 
13 A, may be omitted. The sampling time and sample volume for each run 
shall be at least 60 minutes and 0.85 dscm (30 dscf).
    (3) The equivalent P2O5 feed rate (P) shall be computed 
for each run using the following equation:
P=Mp Rp

Where:

Mp=total mass flow rate of phosphorus-bearing feed, metric ton/
hr (ton/hr).
Rp=P2O5 content, decimal fraction.

    (i) The accountability system of Sec. 63.604 (a) and (b) shall be 
used to determine the mass flow rate (Mp) of the phosphorus-
bearing feed.
    (ii) The Association of Official Analytical Chemists (AOAC) Method 
9 (incorporated by reference--see 40 CFR 60.17) shall be used to 
determine the P2O5 content (Rp) of the feed.
    (4) To comply with Sec. 63.604(d) (1) or (2), the owner or operator 
shall use the monitoring systems in Sec. 63.604(c) to determine the 
average pressure loss of the gas stream across each scrubber in the 
process scrubbing system and to determine the average flow rate of the 
scrubber liquid to each scrubber in the process scrubbing system during 
each of the total fluoride runs. The arithmetic averages of the three 
runs shall be used as the baseline average values for the purposes of 
Sec. 63.604(d) (1) or (2).
    (d) Each owner or operator of a new or existing phosphate rock 
dryer shall demonstrate compliance with the particulate matter 
standards in Sec. 63.602 or Sec. 63.603 as follows:
    (1) The emission rate (E) of particulate matter shall be computed 
for each run using the following equation:

E=(cs Qsd)/(P K)

Where:

E=emission rate of particulate matter, kg/Mg (lb/ton) of phosphate 
rock feed.
cs=concentration of particulate matter, g/dscm (g/dscf).
Qsd=volumetric flow rate of effluent gas, dscm/hr (dscf/hr).
P=phosphate rock feed rate, Mg/hr (ton/hr).
K=conversion factor, 1000 g/kg (453.6 g/lb).

    (2) Method 5 (40 CFR part 60, appendix A) shall be used to 
determine the particulate matter concentration (cs) and volumetric 
flow rate (Qsd) of the effluent gas. The sampling time and sample 
volume for each run shall be at least 60 minutes and 0.85 dscm (30 
dscf).
    (3) The system of Sec. 63.604(a) shall be used to determine the 
phosphate rock feed rate (P) for each run.
    (4) To comply with Sec. 63.604 (d)(1) or (2), the owner or operator 
shall use the monitoring systems in Sec. 63.604(c) to determine the 
average pressure loss of the gas stream across each scrubber in the 
process scrubbing system and to determine the average flow rate of the 
scrubber liquid to each scrubber in the process scrubbing system during 
each of the particulate matter runs. The arithmetic average of the one-
hour averages determined during the three test runs shall be used as 
the baseline average values for the purposes of Sec. 63.604 (d)(1) or 
(2).
    (e) Each owner or operator of a new or existing phosphate rock 
calciner shall

[[Page 68448]]

demonstrate compliance with the particulate matter standards in 
Secs. 63.602 and 63.603 as follows:
    (1) Method 5 (40 CFR part 60, appendix A) shall be used to 
determine the particulate matter concentration. The sampling time and 
volume for each test run shall be at least 2 hours and 1.70 dscm.
    (2) To comply with Sec. 63.604(d)(1) or (2), the owner or operator 
shall use the monitoring systems in Sec. 63.604(c) to determine the 
average pressure loss of the gas stream across each scrubber in the 
process scrubbing system and to determine the average flow rate of the 
scrubber liquid to each scrubber in the process scrubbing system during 
each of the particulate matter runs. The arithmetic average of the one-
hour averages determined during the three test runs shall be used as 
the baseline average values for the purposes of Sec. 63.604 (d)(1) or 
(2).
    (f) Each owner or operator of a new or existing purified phosphoric 
acid manufacturing plant shall establish and maintain an inventory 
system to determine the mass of methyl isobutyl ketone added to each 
process line at an affected source. For the purposes of determining 
compliance with the requirements of Sec. 63.602(f) or Sec. 63.603(f), 
the mass of methyl isobutyl ketone added to the process at any time 
shall be apportioned on the basis of tons of equivalent P2O5 feed, as 
determined under the requirements of Secs. 63.604(a) and 63.604(b), for 
production occurring during the corresponding period of time.


Sec. 63.606  Notification requirements.

    Each owner or operator subject to the requirements of this subpart 
shall comply with the notification requirements in Sec. 63.9.


Sec. 63.607  Recordkeeping requirements.

    Each owner or operator subject to the requirements of this subpart 
shall comply with the recordkeeping requirements in Sec. 63.10.


Sec. 63.608  Reporting requirements.

    (a) The owner or operator of an affected source shall comply with 
the reporting requirements specified in Sec. 63.10 as follows:
    (1) Performance test report. As required by Sec. 63.10, the owner 
or operator shall report the results of the initial performance test as 
part of the notification of compliance status required in Sec. 63.9.
    (2) Excess emissions report. As required by Sec. 63.10, the owner 
or operator of an affected source shall submit an excess emissions 
report for any event when an operating parameter limit is exceeded. The 
report shall contain the information specified in Sec. 63.10. When no 
exceedances of a parameter have occurred, such information shall be 
included in the report. The report shall be submitted semiannually and 
shall be delivered or postmarked by the 30th day following the end of 
the calendar half. If excess emissions are reported, the owner or 
operator shall report quarterly until a request to reduce reporting 
frequency is approved as described in Sec. 63.10.
    (3) Summary report. If the total duration of control system 
exceedances for the reporting period is less than 1 percent of the 
total operating time for the reporting period, the owner or operator 
shall submit a summary report containing the information specified in 
Sec. 63.10 rather than the full excess emissions report, unless 
required by the Administrator. The summary report shall be submitted 
semiannually and shall be delivered or postmarked by the 30th day 
following the end of the calendar half.
    (4) If the total duration of control system parameter exceedances 
for the reporting period is 1 percent or greater of the total operating 
time for the reporting period, the owner or operator shall submit a 
summary report and the excess emissions report.


Sec. 63.609  Compliance dates.

    (a) Each owner or operator of an existing phosphoric acid 
manufacturing plant shall achieve compliance with the requirements of 
this subpart no later than (Three Years After Date of Publication of 
Final Rule).
    (b) Each owner or operator of a phosphoric acid manufacturing plant 
that commences construction or reconstruction after (Date of 
Publication of Final Rule) shall achieve compliance with the 
requirements of this subpart by (Date of Publication of Final Rule) or 
upon startup of operations, whichever is later.


Sec. 63.610  Exemption from new source performance standards.

    Any process component subject to the provisions of this subpart is 
exempted from any otherwise applicable new source performance standard 
contained in 40 CFR Part 60.
    3. Part 63 is amended by adding subpart BB consisting of 
Secs. 63.620 through 63.630 to read as follows:
Subpart BB--National Emission Standards for Hazardous Air Pollutants 
From Phosphate Fertilizers Production Plants
Sec.
63.620  Applicability.
63.621  Definitions.
63.622  Standards for existing sources.
63.623  Standards for new sources.
63.624  Monitoring requirements.
63.625  Performance tests and procedures.
63.626  Notification requirements.
63.627  Recordkeeping requirements.
63.628  Reporting requirements.
63.629  Compliance dates.
63.630  Exemption from exemption from new source performance 
standards.

Subpart BB--National Emission Standards for Hazardous Air 
Pollutants From Phosphate Fertilizers Production Plants


Sec. 63.620  Applicability.

    (a) Except as provided in paragraph (c) of this section, the 
requirements of this subpart apply to the owner or operator of each new 
or existing phosphate fertilizers production plant.
    (b) The requirements of this subpart apply to emissions of 
hazardous air pollutants (HAPs) emitted from the following affected 
sources at a new or existing phosphate fertilizers production plant:
    (1) Each diammonium and/or monoammonium phosphate plant. The 
requirements of this subpart apply to the following emission points 
which are components of a diammonium and/or monoammonium phosphate 
plant: reactors, granulators, dryers, coolers, screens, and mills.
    (2) Each granular triple superphosphate plant. The requirements of 
this subpart apply to the following emission points which are 
components of a granular triple superphosphate plant: mixers, curing 
belts (dens), reactors, granulators, dryers, coolers, screens, and 
mills.
    (3) Each granular triple superphosphate storage building located at 
a granular triple superphosphate plant. The requirements of this 
subpart apply to the following emission points which are components of 
a granular triple superphosphate storage building: storage or curing 
buildings, conveyors, elevators, screens, and mills.
    (c) The requirements of this subpart do not apply to the owner or 
operator of a new or existing phosphate fertilizers production plant 
for which the owner or operator demonstrates, to the satisfaction of 
the Administrator, that the facility is not a major source as defined 
in Sec. 63.2.


Sec. 63.621  Definitions.

    Terms used in this subpart are defined in the Clean Air Act, in 
Sec. 63.2, or in this section as follows:
    Diammonium and/or monoammonium phosphate plant means any plant 
manufacturing granular diammonium and/or monoammonium

[[Page 68449]]

phosphate by reacting phosphoric acid with ammonia.
    Equivalent P2O5 feed means the quantity of phosphorus, 
expressed as phosphorous pentoxide, fed to the process.
    Equivalent P2O5 stored means the quantity of phosphorus, 
expressed as phosphorus pentoxide, being cured or stored in the 
affected facility.
    Fresh granular triple superphosphate means granular triple 
superphosphate produced no more than 10 days prior to the date of the 
performance test.
    Granular triple superphosphate plant means any facility, not 
including storage buildings, manufacturing granular triple 
superphosphate by reacting phosphate rock with phosphoric acid.
    Granular triple superphosphate storage building means any facility 
curing or storing fresh granular triple superphosphate.
    Total fluorides means elemental fluorine and all fluoride 
compounds, including the HAP hydrogen fluoride, as measured by 
reference methods specified in 40 CFR Part 60, Appendix A, Method 13 A 
or B, or by equivalent or alternative methods approved by the 
Administrator pursuant to Sec. 63.7(f).


Sec. 63.622  Standards for existing sources.

    (a) Diammonium and/or monoammonium phosphate plant. On and after 
the date on which the performance test required to be conducted by 
Secs. 63.7 and 63.625 is completed, no owner or operator subject to the 
provisions of this subpart shall cause to be discharged into the 
atmosphere from any affected source any gases which contain total 
fluorides in excess of 30 grams/metric ton of equivalent P2O5 
feed (0.060 lb/ton).
    (b) Granular triple superphosphate plant. On and after the date on 
which the performance test required to be conducted by Secs. 63.7 and 
63.625 is completed, no owner or operator subject to the provisions of 
this subpart shall cause to be discharged into the atmosphere from any 
affected source any gases which contain total fluorides in excess of 75 
grams/metric ton of equivalent P2O5 feed (0.15 lb/ton).
    (c) Granular triple superphosphate storage building. On and after 
the date on which the performance test required to be conducted by 
Secs. 63.7 and 63.625 is completed, no owner or operator subject to the 
provisions of this subpart shall cause to be discharged into the 
atmosphere from any affected source any gases which contain total 
fluorides in excess of 0.250 grams/hr/metric ton of equivalent 
P2O5 stored (5.0 X 10-\4\ lb/hr/ton of equivalent 
P2O5 stored).


Sec. 63.623  Standards for new sources.

    (a) Diammonium and/or monoammonium phosphate plant. On and after 
the date on which the performance test required to be conducted by 
Secs. 63.7 and 63.625 is completed, no owner or operator subject to the 
provisions of this subpart shall cause to be discharged into the 
atmosphere from any affected source any gases which contain total 
fluorides in excess of 29.0 grams/metric ton of equivalent 
P2O5 feed (0.0580 lb/ton).
    (b) Granular triple superphosphate plant. On and after the date on 
which the performance test required to be conducted by Secs. 63.7 and 
63.625 is completed, no owner or operator subject to the provisions of 
this subpart shall cause to be discharged into the atmosphere from any 
affected source any gases which contain total fluorides in excess of 
61.50 grams/metric ton of equivalent P2O5 feed (0.1230 lb/
ton).
    (c) Granular triple superphosphate storage building. On and after 
the date on which the performance test required to be conducted by 
Secs. 63.7 and 63.625 is completed, no owner or operator subject to the 
provisions of this subpart shall cause to be discharged into the 
atmosphere from any affected source any gases which contain total 
fluorides in excess of 0.250 grams/hr/metric ton of equivalent 
P2O5  stored (5 x 10 1-4 lb/hr/ton of equivalent 
P2O5  stored).


Sec. 63.624  Monitoring requirements.

    (a) Each owner or operator of a new or existing diammonium and/or 
monoammonium phosphate plant or granular triple superphosphate plant 
subject to the provisions of this subpart shall install, calibrate, 
maintain, and operate a monitoring system which can be used to 
determine and permanently record the mass flow of phosphorus-bearing 
feed material to the process. The monitoring system shall have an 
accuracy of 5 percent over its operating range.
    (b) Each owner or operator of a new or existing diammonium and/or 
monoammonium phosphate plant or granular triple superphosphate plant 
subject to the provisions of this subpart shall maintain a daily record 
of equivalent P2O5  feed by first determining the total mass 
rate in metric ton/hour of phosphorus bearing feed using a monitoring 
system for measuring mass flowrate which meets the requirements of 
paragraph (a) of this section and then by proceeding according to 
Sec. 63.625(c)(3).
    (c) Each owner or operator of a new or existing diammonium and/or 
monoammonium phosphate plant, granular triple superphosphate plant, or 
granular triple superphosphate storage building using a wet scrubbing 
emission control system shall install, calibrate, maintain, and operate 
the following monitoring systems:
    (1) A monitoring system which continuously measures and permanently 
records the total pressure drop across each scrubber in the process 
scrubbing system. The monitoring system shall be certified by the 
manufacturer to have an accuracy of 5 percent over its 
operating range.
    (2) A monitoring system which continuously measures and permanently 
records the flow rate of the scrubbing liquid to each scrubber in the 
process scrubbing system. The monitoring system shall be certified by 
the manufacturer to have an accuracy of 5 percent over its 
operating range.
    (d) The owner or operator of any granular triple superphosphate 
storage building subject to the provisions of this subpart shall 
maintain an accurate account of granular triple superphosphate in 
storage to permit the determination of the amount of equivalent 
P2O5  stored.
    (e) Each owner or operator of a new or existing granular triple 
superphosphate storage building subject to the provisions of this 
subpart shall maintain a daily record of total equivalent 
P2O5  stored by multiplying the percentage P2O5  
content, as determined by Sec. 63.625(d)(3)(C), times the total mass of 
granular triple superphosphate stored.
    (f) Any new or existing source subject to emissions limitations for 
total fluorides or particulate matter contained in this subpart shall 
comply with either paragraph (f) (1) or (2) of this section:
    (1) For a new or existing affected source, following the date on 
which the performance test required in Sec. 63.625 is completed, any 
three-hour average of the total pressure drop across the scrubber(s) or 
of the flow rate of the scrubbing liquid to the scrubber(s) in the 
process scrubbing system which exceeds  ten percent of the 
value determined as a requirement of Sec. 63.625 (c)(4) or (d)(4) shall 
constitute a violation of the applicable emission limit contained in 
this subpart unless the affected source performs and passes a 
performance test as required in Sec. 63.625 within thirty days 
following the exceedance. Any owner or operator who intends to conduct 
a performance test pursuant to this paragraph shall notify the 
Administrator of that intention within one business day of the 
parameter exceedance. Any owner or operator conducting a performance 
test pursuant to this paragraph shall establish and maintain during 
that test

[[Page 68450]]

the same operating conditions as were determined during the exceedance 
of the operating range.
    (2) The owner or operator of any new or existing affected source 
shall establish operating ranges for the total pressure drop across or 
of the flow rate of the scrubbing liquid to each scrubber in the 
process scrubbing system for the purpose of assuring compliance with 
applicable emission limits required in this subpart. Operating ranges 
may be based upon values recorded during previous performance tests 
using the test methods required in this subpart and established in the 
manner required in Sec. 63.625 (c)(4) or (d)(4). As an alternative the 
owner or operator can base the operating ranges upon the results of 
performance tests conducted specifically for the purposes of this 
paragraph using the test methods required in this subpart and 
established in the manner required in Sec. 63.625 (c)(4) or (d)(4). The 
source shall certify that the control devices and processes have not 
been modified subsequent to the testing upon which the data used to 
establish the operating ranges were obtained. Following the approval by 
the permitting authority of operating ranges for the affected source, 
any three-hour average of the values of total pressure drop or flow 
rate of the scrubbing liquid which exceeds the approved operating 
ranges shall constitute a violation of the applicable emission limit 
contained in this subpart.


Sec. 63.625  Performance tests and procedures.

    (a) Each owner or operator of a new or existing phosphate 
fertilizers production plant subject to the provisions of this subpart 
shall conduct a performance test to demonstrate compliance with the 
applicable emission standard for each diammonium and/or monoammonium 
phosphate plant, granular triple superphosphate plant, or granular 
triple superphosphate storage building. If the affected source has 
multiple control devices and/or emission points subject to the 
provisions of this subpart, those control devices and/or emission 
points shall be tested simultaneously. The owner or operator shall 
conduct the performance test according to the procedures in the General 
Provisions in subpart A of this part and in this section.
    (b) In conducting performance tests, each owner or operator of an 
affected source shall use as reference methods and procedures the test 
methods in 40 CFR Part 60, Appendix A, or other methods and procedures 
as specified in this section, except as provided in Sec. 63.7(f).
    (c) Each owner or operator of a new or existing diammonium and/or 
monoammonium phosphate plant or granular triple superphosphate plant 
shall determine compliance with the applicable total fluorides 
standards in Sec. 63.622 or Sec. 63.623 as follows:
    (1) The emission rate (E) of total fluorides shall be computed for 
each run using the following equation:
[GRAPHIC] [TIFF OMITTED] TP27DE96.010

Where:

E=emission rate of total fluorides, g/metric ton (lb/ton) of 
equivalent P2O5 feed.
Csi=concentration of total fluorides from emission point ``i,'' 
mg/dscm (mg/dscf).
Qsdi=volumetric flow rate of effluent gas from emission point 
``i,'' dscm/hr (dscf/hr).
N=number of emission points associated with the affected facility.
P=equivalent P2O5 feed rate, metric ton/hr (ton/hr).
K=conversion factor, 1000 mg/g (453,600 mg/lb).

    (2) Method 13A or 13B (40 CFR part 60, appendix A) shall be used to 
determine the total fluorides concentration (Csi) and volumetric 
flow rate (Qsdi) of the effluent gas from each of the emission 
points. If Method 13B is used, the fusion of the filtered material 
described in section 7.3.1.2 and the distillation of suitable aliquots 
of containers 1 and 2, described in sections 7.3.3 and 7.3.4 in Method 
13A, may be omitted. The sampling time and sample volume for each run 
shall be at least one hour and 0.85 dscm (30 dscf).
    (3) The equivalent P2O5 feed rate (P) shall be computed 
for each run using the following equation:

P=Mp Rp

Where:

Mp=total mass flow rate of phosphorus-bearing feed, metric ton/
hr (ton/hr).
Rp=P2O5 content, decimal fraction.

    (i) The accountability system of Sec. 63.624 (a) and (b) shall be 
used to determine the mass flow rate (Mp) of the phosphorus-
bearing feed.
    (ii) The Association of Official Analytical Chemists (AOAC) Method 
9 (incorporated by reference--see 40 CFR 60.17) shall be used to 
determine the P2O5 content (Rp) of the feed.
    (4) To comply with Sec. 63.624(f) (1) or (2), the owner or operator 
shall use the monitoring systems in Sec. 63.624(c) to determine the 
average pressure loss of the gas stream across each scrubber in the 
process scrubbing system and to determine the average flow rate of the 
scrubber liquid to each scrubber in the process scrubbing system during 
each of the total fluoride runs. The arithmetic averages of the three 
runs shall be used as the baseline average values for the purposes of 
Sec. 63.624(f) (1) or (2).
    (d) Each owner or operator of a new or existing granular triple 
superphosphate storage building shall determine compliance with the 
applicable total fluorides standards in Sec. 63.622 or Sec. 63.623 as 
follows:
    (1) The owner or operator shall conduct performance tests only when 
the following quantities of product are being cured or stored in the 
facility.
    (i) Total granular triple superphosphate is at least 10 percent of 
the building capacity, and
    (ii) Fresh granular triple superphosphate is at least 20 percent of 
the total amount of triple superphosphate, or
    (iii) If the provision in paragraph (d)(1)(ii) of this section 
exceeds production capabilities for fresh granular triple 
superphosphate, fresh granular triple superphosphate is equal to at 
least 5 days maximum production.
    (2) In conducting the performance test, the owner or operator shall 
use as reference methods and procedures the test methods in Part 60, 
Appendix A, or other methods and procedures as specified in this 
section, except as provided in Sec. 63.7(f).
    (3) The owner or operator shall determine compliance with the total 
fluorides standard in Secs. 63.622 and 63.623 as follows:
    (i) The emission rate (E) of total fluorides shall be computed for 
each run using the following equation:
[GRAPHIC] [TIFF OMITTED] TP27DE96.011

Where:

E=emission rate of total fluorides, g/hr/metric ton (lb/hr/ton) of 
equivalent P2O5 stored.
Csi=concentration of total fluorides from emission point ``i,'' 
mg/dscm (mg/dscf).
Qsdi=volumetric flow rate of effluent gas from emission point 
``i,'' dscm/hr (dscf/hr).
N=number of emission points in the affected facility.
P=equivalent P2O5 stored, metric tons (tons).
K=conversion factor, 1000 mg/g (453,600 mg/lb).

    (ii) Method 13A or 13B (40 CFR part 60, appendix A) shall be used 
to determine the total fluorides concentration (Csi) and 
volumetric flow rate (Qsdi) of the effluent gas from each of the 
emission points. If Method 13 B is used, the fusion of the filtered 
material described in section 7.3.1.2 and the distillation of suitable 
aliquots of containers 1 and 2, described in Sections 7.3.3 and 7.3.4 
in Method 13 A,

[[Page 68451]]

may be omitted. The sampling time and sample volume for each run shall 
be at least one hour and 0.85 dscm (30 dscf).
    (iii) The equivalent P2O5 feed rate (P) shall be computed 
for each run using the following equation:

P=Mp Rp

Where:
Mp=amount of product in storage, metric ton (ton).
Rp=P2O5 content of product in storage, weight 
fraction.

    (A) The accountability system of Sec. 63.624 (d) and (e) shall be 
used to determine the amount of product (Mp) in storage.
    (B) The Association of Official Analytical Chemists (AOAC) Method 9 
(incorporated by reference--see 40 CFR 60.17) shall be used to 
determine the P2O5 content (Rp) of the product in 
storage.
    (4) To comply with Sec. 63.624(f) (1) or (2), the owner or operator 
shall use the monitoring systems in Sec. 63.624(c) to determine the 
average pressure loss of the gas stream across each scrubber in the 
process scrubbing system and to determine the average flow rate of the 
scrubber liquid to each scrubber in the process scrubbing system during 
each of the total fluoride runs. The arithmetic averages of the three 
runs shall be used as the baseline average values for the purposes of 
Sec. 63.624(f) (1) or (2).


Sec. 63.626  Notification requirements.

    Each owner or operator subject to the requirements of this subpart 
shall comply with the notification requirements in Sec. 63.9.


Sec. 63.627  Recordkeeping requirements.

    Each owner or operator subject to the requirements of this subpart 
shall comply with the recordkeeping requirements in Sec. 63.10.


Sec. 63.628  Reporting requirements.

    (a) The owner or operator of an affected source shall comply with 
the reporting requirements specified in Sec. 63.10 as follows:
    (1) Performance test report. As required by Sec. 63.10, the owner 
or operator shall report the results of the initial performance test as 
part of the notification of compliance status required in Sec. 63.9.
    (2) Excess emissions report. As required by Sec. 63.10, the owner 
or operator of an affected source shall submit an excess emissions 
report for any event when an operating parameter limit is exceeded. The 
report shall contain the information specified in Sec. 63.10. When no 
exceedances of a parameter have occurred, such information shall be 
included in the report. The report shall be submitted semiannually and 
shall be delivered or postmarked by the 30th day following the end of 
the calendar half. If excess emissions are reported, the owner or 
operator shall report quarterly until a request to reduce reporting 
frequency is approved as described in Sec. 63.10.
    (3) Summary report. If the total duration of control system 
exceedances for the reporting period is less than 1 percent of the 
total operating time for the reporting period, the owner or operator 
shall submit a summary report containing the information specified in 
Sec. 63.10 rather than the full excess emissions report, unless 
required by the Administrator. The summary report shall be submitted 
semiannually and shall be delivered or postmarked by the 30th day 
following the end of the calendar half.
    (4) If the total duration of control system parameter exceedances 
for the reporting period is 1 percent or greater of the total operating 
time for the reporting period, the owner or operator shall submit a 
summary report and the excess emissions report.
    (b) [Reserved]


Sec. 63.629  Compliance dates.

    (a) Each owner or operator of an existing phosphate fertilizers 
production plant shall achieve compliance with the requirements of this 
subpart no later than (Three Years After Date of Publication of Final 
Rule).
    (b) Each owner or operator of a phosphate fertilizers production 
plant that commences construction or reconstruction after (Date of 
Publication of Final Rule), shall achieve compliance with the 
requirements of this subpart by (Date of Publication of Final Rule) or 
upon startup of operations, whichever is later.


Sec. 63.630  Exemption from new source performance standards.

    Any process component subject to the provisions of this subpart is 
exempted from any otherwise applicable new source performance standard 
contained in 40 CFR Part 60.

[FR Doc. 96-31706 Filed 12-26-96; 8:45 am]
BILLING CODE 6560-50-P