[Federal Register Volume 62, Number 146 (Wednesday, July 30, 1997)]
[Notices]
[Pages 40792-40795]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-20010]


 ========================================================================
 Notices
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains documents other than rules 
 or proposed rules that are applicable to the public. Notices of hearings 
 and investigations, committee meetings, agency decisions and rulings, 
 delegations of authority, filing of petitions and applications and agency 
 statements of organization and functions are examples of documents 
 appearing in this section.
 
 ========================================================================
 

  Federal Register / Vol. 62, No. 146 / Wednesday, July 30, 1997 / 
Notices  

[[Page 40792]]


=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF AGRICULTURE

Forest Service


Final Conformity Determination for Proposed Carlota Copper 
Project, Pinal and Gila Counties, Arizona

AGENCY: Forest Service, USDA.

ACTION: Notice: Final Conformity Determination for the Proposed Carlota 
Copper Project, Pinal and Gila Counties, Arizona.

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

SUMMARY: In accordance with the federal Conformity Rule (November 30, 
1993, 40 CFR 93.150-160), the United States Department of Agriculture, 
Forest Service--Tonto National Forest (Tonto NF) has reviewed the air 
quality analysis conducted for the proposed Carolta Copper Project. The 
project is proposed to be within Hayden/Miami Planning Area and the 
Miami Sulfur Dioxide Nonattainment Area, designated nonattainment areas 
for particulate matter less than 10 microns in aerodynamic diameter 
(PM10) and sulfur dioxide (SO2), respectively. 
The Tonto NF's review has been conducted consistent with the 
requirements of 40 CFR part 93, Subpart B: ``Determining Conformity of 
General Federal Activities to State or Federal Implementation Plans 
(SIP)'', issued on November 30, 1993.
    The Tonto NF has determined that total annual emissions of 
SO2 from the proposed project are less than the de minimis 
emission threshold (40 CFR part 93) that triggers the requirement to 
conduct a conformity determination.
    Annual PM10 emissions have been determined to exceed the 
PM10 de minimis threshold and the Tonto NF has prepared a 
conformity determination for this pollutant. As per the requirement in 
40 CFR 93.153(h)(1), this Federal Register notice lists the proposed 
activities that are presumed to conform and the bases for the 
presumptions. A comprehensive presentation of the bases for the 
conformity presumptions are included in the report, ``Final Conformity 
Determination: Carlota Copper Project, Pinal and Gila Counties, 
Arizona,'' USDA, Forest Service--Tonto National Forest, July 1997 (the 
report). This document is available to the public for reference 
purposes.

ADDRESSES: The report, ``Final Conformity Determination: Carlota Copper 
Project, Pinal and Gila Counties, Arizona,'' USDA, Forest Service--
Tonto National Forest, Arizona, July 1997, is available for reference 
purposes at the following locations: Tonto National Forest Supervisor's 
Office, Phoenix, Arizona; Globe Ranger District Office, Globe, Arizona.

FOR FURTHER INFORMATION CONTACT:
Paul M. Stewart, Tonto National Forest, 2324 E. McDowell Road, Phoenix, 
AZ 85006, (602) 225-5200.

SUPPLEMENTARY INFORMATION: 

I. Background

    The Carlota Copper Company has submitted a Plan of Operations 
(1992), a subsequent Update to the Plan of Operations (1993), and 
numerous letter submittals documenting changes to the Plan of 
Operations (as documented in Chapter 2 of the Final Environmental 
Impact Statement for the Carlota Copper Project) to the United States 
Department of Agriculture, (USDA) Forest Service--Tonto National Forest 
(Tonto NF) for the construction, operation, and reclamation of the 
Carlota Copper Project (project), a copper mining and processing 
operation. The project is designated by rule and regulation as a Class 
II minor source to be permitted by the Arizona Department of 
Environmental Quality (ADEQ). The proposed project is located on 
private land and on lands administered by the Tonto NF. Specifically, 
the project is located in Gila and Pinal Counties, approximately 7 
miles west of Miami, Arizona.
    A portion of the project is proposed to be within the northern part 
of an area that has been designated by the United States Environmental 
Protection Agency (EPA) as a nonattainment area for the annual 24-hour 
National Ambient Air Quality Standard (NAAQS) for particulate matter 
less than 10 microns in aerodynamic diameter (PM10). The 
first phase of the PM10 nonattainment designation occurred 
August 7, 1987, (52 Federal Register (FR) 29383) when EPA identified 
and listed the Group I and Group II area in each state. The Hayden/
Miami Planning Area was designated a Group I area. A Group I area is an 
area that has been estimated by EPA to have a 95 percent or greater 
probability of exceeding the PM10 standards (Hayden 
PM10 State Implementation Plan (SIP) p. 14).
    On November 15, 1990, EPA designated all Group I areas as 
``nonattainment'' for PM10. At the same time, EPA announced 
that all areas designated as nonattainment area for PM10 
were classified as ``moderate'' nonattainment areas. Therefore, the 
Hayden/Miami Planning Area is classified as a moderate nonattainment 
area for PM10. A moderate area is a nonattainment area that 
the Administrator has determined can practicably attain the NAAQS for 
PM10 by the attainment date for moderate areas (as 
expeditiously as practicable but no later than the sixth calendar year 
after the area's designation as nonattainment). (Clean Air Act, Section 
188(a-c)). The Hayden/Miami Planning Area consists of:
     Township: T4S, R16E; T5S, R16E; T6S, R16E,
     The portion of Township T3S, R16E that does not lie on the 
San Carlos Indian Reservation, and
     The rectangle formed by, and including Townships: T1N, 
R13E; T1N, R15E; T6S, R13E; T6S, R15E.
    The portion of the project area that is within the moderate 
nonattainment area is in the rectangle formed by the four townships. 
Specifically, the project area is located within Township T1N, R13E.
    On November 10, 1994, ADEQ petitioned EPA to realign the Hayden/
Miami Planning Area PM10 nonattainment boundary. Based on 
topographical and climatological differences, as well as no monitored 
exceedances of the PM10 NAAQS in the Miami area, ADEQ 
requested that Townships T1N, R13E-R15E and T1S, R13E-R15E be excluded 
from the nonattainment area. This area includes the proposed Carlota 
Copper Project area. To date, there has been no action by EPA to 
realign the Hayden/Miami Planning Area, Therefore, the proposed project 
remains within the nonattainment area.
    Tonto NF concurs with ADEQ's classification of the proposed Carlota 
Copper Project as a Class II minor

[[Page 40793]]

source in a nonattainment area. Consequently, the New Source Review 
(NSR) permitting programs (i.e., Prevention of Significant 
Deterioration (PSD) review for attainment area and nonattainment area 
(NAA) review for nonattainment areas) do not apply. Because the Carlota 
Copper Project is not subject to these major source permitting 
requirements, the Carlota Copper Project cannot take advantage of the 
conformity determination exclusion offered under 40 CFR 93.153(d)(1) 
and a formal conformity determination is required.
    The area has also been classified as a Priority IA Region (40 CFR 
52.121) for sulfur dioxide (SO2). States are required to 
prepare and submit a SIP that demonstrates attainment and maintenance 
of the NAAQS in Priority I Regions. The Priority IA classification is 
for any area that has been designated a Priority I region primarily 
because of emissions from a single source. In this case, the 
designation is based on copper smelting operations in Miami, Arizona. 
The area is in attainment for all other criteria pollutants: carbon 
monoxide, nitrogen dioxide, lead, and ozone.
    Section 110 of the Clean Air Act requires that the State of Arizona 
prepare and submit to the EPA a SIP to reduce particulate emissions to 
achieve and maintain attainment of both the SO2 and 
PM10 NAAQS. ADEQ has developed a PM10 SIP 
designed to reduce and maintain ambient concentrations of 
PM10 to levels below the NAAQS for PM10. EPA has 
proposed partial approval of the Hayden PM10 SIP. To date, 
there has been no final approval of the SIP. ADEQ is in the process of 
developing the Miami SO2 SIP.
    Due to the proposed location of the project in the nonattainment 
area and the Tonto NF's affirmative role as Federal Land Manager, the 
Tonto NF has the responsibility under the Clean Air Act section 
176(c)(4) (November 15, 1990) to make a determination as to whether the 
proposed project conforms with all aspects of the applicable SIP for 
the area. The Tonto NF has reviewed the air quality analysis conducted 
for this project consistent with the requirements of 40 CFR part 93 
Subpart B: ``Determining Conformity of General Federal Actions to State 
or Federal Implementation Plans (SIP)'', issued on November 30, 1993.
    The Tonto NF has determined that total annual emissions of 
SO2 from the project are less than the de minimis emission 
threshold (40 CFR 93.153(b)(1)) that triggers the requirement to 
conduct a conformity determination. Therefore, although the Miami area 
has been designated a nonattainment area for SO2, a 
conformity determination for SO2 emissions is not required. 
Annual PM10 emissions have been determined to exceed the de 
minimis threshold and the Tonto NF has determined that a conformity 
determination is required for PM10.

II. Requirements of the Conformity Determination

    In the absence of a fully approved PM10 SIP for the 
Hayden/Miami planning area, according to 40 CFR 93.151, the federal 
conformity regulations contained in 40 CFR part 93 apply to the Carlota 
Copper Project.\1\ These regulations require a demonstration that total 
direct and indirect emissions from the project will not:
---------------------------------------------------------------------------

    \1\ Given the receipt of several public comments on the issue of 
requirements of a conformity determination, it is important to note 
that an increment consumption analysis is not a required portion of 
a federal conformity determination. For the Carlota Copper Project, 
this position is justified on two levels: (1) The conformity rule 
(40 CFR part 93) explicitly lists the requirements of a conformity 
determination and does not include an increment consumption analysis 
on the list of requirements; and (2) because the proposed Carlota 
Copper Project is classified as an Arizona Class II (minor) source 
in a nonattainment area, an increment consumption analysis is 
expressly not required under state or federal rules and regulations. 
Concurrence on this position has been offered by the Tonto NF, ADEQ, 
EPA Region IX, and the Pinal County Air Pollution Control District. 
As a measure of the significance of impacts from the Carlota Copper 
Project, the Tonto NF included an assessment of increment 
consumption in the Final Environmental Impact Statement.
---------------------------------------------------------------------------

    1. Cause or contribute to any new violation of any standard in the 
area,
    2. Interfere with provisions in the applicable SIP for maintenance 
of any standard,
    3. Increase the frequency or severity of any existing violation of 
any standard in any area, or
    4. Delay timely attainment of any standard or any required interim 
emission reductions or other milestones in the SIP for purposes of
    (a) Demonstration of reasonably further progress (RFP),
    (b) Demonstration of attainment, or
    (c) Maintenance plan.
    The Tonto NF has determined that this Conformity Determination is 
to establish through a local modeling analysis that PM10 
emissions from Carlota emission sources on private and public lands 
will not create any new exceedances of the PM10 NAAQS 
(``general'' requirement ``1,'' above). For the reasons stated below, 
the activities of the proposed Carlota Copper Project conform to 
general requirements 2, 3, and 4.
    The proposed SIP only serves to bring ambient PM10 
concentrations in the Hayden area to levels that are below the NAAQS. 
The PM10 nonattainment designation for the Hayden/Miami 
Planning Area is a result of expected exceedances of the 
PM10 NAAQS proximate to the coppersmelting activities in the 
town of Hayden. As a result, the ``design value'' (i.e., the predicted 
ambient level of PM10 upon which the controls in the SIP are 
based) pertains to particulate levels in Hayden (not to the proposed 
project site). Hayden is located in the southern tip of Gila County, 
approximately 25 miles south of the proposed project.
    Ambient concentrations monitored in the project area (see the 
discussion of background concentrations in the report) and 
PM10 monitoring in the town of Miami demonstrate that 
exceedances of the NAAQS in the nonattainment area have not occurred 
outside of the town of Hayden. Review of the local modeling analysis 
for the Carlota Copper Project (discussed in detail in the report) 
indicate that particulate impacts in Hayden (25 miles south of the 
project) due to emissions from the project are expected to be 
negligible (or zero). The proposed project is not expected to interfere 
with maintenance of the standard in Hayden and the local modeling 
analysis demonstrates protection of the NAAQS in the project area. The 
Tonto NF has therefore determined the proposed action to conform with 
requirement 2.
    Similarly, requirement 3 is met because the project is not expected 
to cause any impacts in Hayden, thus emissions from the project will 
not increase the frequency or severity of violations of the 
PM10 NAAQS that have been monitored in Hayden. There have 
been no monitored violations of the PM10 NAAQS in the 
proposed project area.
    Lastly, requirement 4 is met because there are no interim emission 
reductions or other milestones in the proposed SIP that pertain to any 
emission sources at the Carlota Copper Project. Particulate emission 
control measures in the proposed SIP pertain only to control of 
PM10 emissions at two specific copper smelters (and 
associated activities) located in Hayden. Any demonstration of 
``reasonable further progress,'' attainment, or compliance with a 
maintenance plan would only pertain to ambient PM10 levels 
in Hayden and/or emission control measures implemented on the subject 
emission sources.

III. Conformity Determination Methodology

    Local Modeling Analysis. The final Conformity Rule (40 CFR part 93) 
specifically allows for the use of a local

[[Page 40794]]

modeling analysis for a conformity determination. 40 CFR 
93.158(a)(4)(l) stipulates:

    ``Where the State agency primarily responsible for the 
applicable SIP determines that an area-wide air quality modeling 
analysis is not needed, the total of direct and indirect emissions 
from the action meet the requirements specified in paragraph (b) of 
this section, based on local air quality modeling analysis * * *''

    Paragraph (b) (40 CFR 93.158) requires that the local air quality 
modeling analysis shows that an action does not cause or contribute to 
any new violation of any standard in any area. Paragraph (b) also 
requires that a local air quality analysis meet the applicable 
requirements of 40 CFR 93.159, Procedures for Conformity Determinations 
of General Federal Actions. The applicable requirements of 93.159 are:
     The analysis must be based on the latest and most accurate 
emission estimation techniques (including estimation of emission 
control efficiencies) available for stationary and area sources of 
emissions, defined as the latest emission factors specified by EPA in 
AP-42 (``Compilation of Emission Factors''), unless more accurate 
emission data are available (93.159.b.2) (site-specific parameters are 
used when available);
     The analysis must be based on the applicable air quality 
models, data bases, and other requirements specified in the most recent 
version of the ``Guideline on Air Quality Models (Revised)'' (1986) 
including supplements (93.159.c); and
     The analysis must be based on the total of direct and 
indirect emissions from the action and must reflect emission scenarios 
that are expected to occur the year during which total emissions are 
expected to be the greatest on an annual basis (93.159.d.2).
    Emissions. For the purposes of a conformity determination, direct 
and indirect emissions are defined as follows (40 CFR 92.152):
     Direct Emissions: Those emissions of a criteria pollutant 
or its precursors that are caused or initiated by the Federal action 
and occur at the same time and place as the action;
     Indirect Emissions: Those emissions of a criteria 
pollutant or its precursors that:
    1. Are caused by the Federal action, but may occur later in time 
and/or may be further removed in distance from the action itself but 
are still reasonably foreseeable; and
    2. The Federal agency can practicably control and will maintain 
control over due to a continuing program responsibility of the Federal 
agency.
    For the Carlota Copper Project, the Tonto NF has determined that 
the emissions inventory prepared for the air quality analysis includes 
the total of direct and indirect emissions from Carlota sources on 
private and Federal lands using the latest emission factors (for 
emission estimates and control efficiencies) specified in AP-42 and 
site-specific parameters when available (40 CFR 93.159(b)(2)). The 
Tonto NF has determined only emissions sources of PM10 at 
the proposed project are of concern with regard to PM10 
conformity requirements. The basis for designation of the area as 
nonattainment was PM10 emissions (not precursors) from 
mining activities (associated with smelting activities in Hayden, AZ). 
Precursors of PM10 were also not incorporated in the SIP 
analysis for the nonattainment area. The Tonto NF maintains that a 
conformity determination based on PM10 emissions will be 
adequate to assess conformity and to protect the PM10 NAAQS 
at the process area boundary.
    The local modeling analysis utilized the EPA-approved ISCST3 
dispersion model (Version 95200) with the dry deposition algorithm. The 
Tonto NF has reviewed the modeling analysis and has determined that the 
model has been run according to the most recent modeling guidelines and 
supplements.
    Emissions from process and non-process sources at the project are 
direct emissions under the definition above. The Tonto NF has 
determined that the hourly and annual emission estimates prepared for 
the air quality analysis are representative of the maximum of 
PM10 emission rates expected to occur over the life of the 
project. The distribution of emission sources in the modeling analysis 
has been assessed by the Tonto NF to be representative of the spatial 
extent of the emissions sources that is expected to produce the maximum 
off-site PM10 impacts over the life of the project (40 CFR 
93.159(d)(2)). Further, the Tonto NF has not identified any other 
emissions or emission sources that the Tonto NF can practicably control 
or maintain control of due to a continuing program responsibility for 
the project. The report includes a detailed description of emission 
sources and controls at the project.
    Offsets. As an option to a modeling analysis, 40 CFR 93.158 allows 
an action to fully offset its emissions within the same nonattainment 
area through a revision to the applicable SIP or an equally enforceable 
measure that effects emission reductions equal to or greater than the 
total of direct and indirect emissions from the action so that there is 
no net increase in emissions of that pollutant 
(Sec. 93.158(a)(5)(iii)). The Tonto NF has determined that since the 
local modeling analysis satisfies the requirements of 40 CFR 93.158(b) 
and because there is not a fully approved SIP for the Hayden/Miami 
Planning Area that could be revised to include offsets, the local 
modeling analysis allowed for in Sec. 93.158(a)(4) is adequate for 
determining the conformity of the action.

IV. Presumption of Conformity

    The United States Department of Agriculture (USDA) Forest Service--
Tonto National Forest has reviewed the air quality analysis conducted 
for the Carlota Copper Project (consistent with the requirement of 40 
CFR part 93, ``Determining Conformity of General Federal Actions to 
State or Federal Implementation Plans (SIP)'', issued on November 30, 
1993).
    For purposes of emissions of sulfur dioxide (SO2), the 
project is proposed to be located in an area designated as 
nonattainment for SO2 (the Miami Sulfur Dioxide 
Nonattainment Area) although there is not an approved SO2 
SIP for the nonattainment area. The Tonto NF has reviewed the air 
quality analysis and determined that predicted direct and indirect 
emissions of SO2 are 26 tons per year based on a required 
AQCP condition (as issued by ADEQ) to use low sulfur content diesel 
fuel. (0.05 percent sulfur by weight) in stationary combustion sources 
and the commitment to use low sulfur diesel fuel in all mobile 
combustion equipment. This is below the de minimis level of 100 tons 
per year for SO2 as defines in the general conformity rule 
(40 CFR 93.153). Because projected annual SO2 emissions from 
the proposed facility are below the de minimis SO2 level, no 
further conformity determination is necessary.
    For purposes of emissions of particulate matter with aerodynamic 
diameter less than 10 microns (PM10), the project is 
proposed to be located in an area designated as a moderate 
nonattainment area for PM10 (the Hayden/Miami Planning 
Area). The air quality analysis for the project indicates that 
predicted direct and indirect emissions of PM10 exceed the 
de minimis level for moderate PM10 areas (100 tons per 
year). Therefore, the Tonto NF has reviewed the local PM10 
emissions modeling analysis for the project and has determined the 
following:
     The methods for estimating direct and indirect emissions 
from the project

[[Page 40795]]

meet the requirements of 40 CFR 93.159. The emissions scenario used in 
the air quality analysis is expected to produce the greatest off-site 
impacts on a daily and annual basis. (A detailed description of the 
emission sources and detailed emissions inventory tables are included 
in the report.)
     The local PM10 emissions modeling methodology 
is appropriate for determining whether emissions from the project will 
cause or contribute to any new violation of the PM10 
National Ambient Air Quality Standard (NAAQS) and meet the requirements 
of 40 CFR 93.159. (A detailed description of the local PM10 
emissions modeling methodology is included in the report.)
     The results of the modeling analysis using the EPA-
approved ISCST3 dispersion model (Version 95200) with the dry 
deposition algorithm predict maximum 24-hour ambient concentrations 
(impact plus background) at the process area boundary to be 110.8 
g/m3. This is below the 24-hour PM10 
NAAQS of 150 g/m3. (A detailed description of the 
modeling analysis results and the printouts of the model input and 
output files are included in the report.)
     The results of the modeling analysis predict the maximum 
average annual ambient concentration at the process area boundary to be 
36.9 g/m3. This is below the annual PM10 
NAAQS STANDARD OF 50 g/m3. \2\
---------------------------------------------------------------------------

    \2\ Predicted maximum concentrations (impact plus background) at 
Top-of-the-World (located within the nonattainment area) area are 
20.4 g/m3 for the 24-hour average and 17.3 
g/m3 for the annual average.
---------------------------------------------------------------------------

     The action does not cause or contribute to any new 
violation of any standard in any area (40 CFR 93.158(b)(2)(i)).
     The action does not increase the frequency or severity of 
any existing violation of any standard in any area (40 CFR 
93.158(b)(2)(ii)).
     The action does not violate any requirements or milestones 
in the SIP (no requirements or milestones are applicable to the 
project) (40 CFR 93.158(c)).
    The Tonto NF has also determined that the planned PM10 controls for 
the project are equivalent to Best Available Control Technology (BACT) 
for sources of PM10 emissions associated with open-pit 
mining operations.
    Based on these determinations, the activities at the Carlota Copper 
Project is presumed to conform to the applicable conformity 
requirements for the project area. The list of activities at the 
Carlota Copper Project that are presumed to conform include:

----------------------------------------------------------------------------------------------------------------
               Process                                                Non-process                               
----------------------------------------------------------------------------------------------------------------
Primary crusher system..............  Topsoil removal.                                                          
Conveyor systems....................  Topsoil unloading to stockpiles.                                          
Secondary crusher system............  Blast hole drilling.                                                      
Boiler..............................  Blasting.                                                                 
Back-up generator...................  Loading/unloading of ore and mine rock.                                   
                                      Hauling or ore and mine rock.                                             
                                      Combustion emissions from mobile equipment.                               
                                      Travel of mine equipment other than haul trucks.                          
                                      Haul road maintenance.                                                    
----------------------------------------------------------------------------------------------------------------

    This presumption of conformity is based on adequate activity 
limits, emission limits, emission controls, and monitoring requirements 
that have been included in the AQCP No. 071437P0-99 for the Carlota 
Copper Project issued by ADEQ. The presumption of conformity assumes 
that the requirements in the permit will be adequately enforced by 
ADEQ. The Tonto NF lists the following permit requirements (contained 
in the Attachment B to the permit) as being critical to the presumption 
of conformity of the Carlota Copper Project:
     Maximum speed limit of 35 mph for all vehicles and an 
average speed for the heavy-duty haul trucks of 15 mph. (Condition 
II.D.1)
     Unpaved roadway treatment with magnesium chloride, calcium 
chloride, or other chemical dust suppressants with equivalent or better 
control efficiency in sufficient quantity and frequency to maintain a 
ground inventory of 0.25 gallons per square yard. (Condition II.E.2)
     Water sprays installed, operated, and maintained 
continuously during the times of operation of the primary crusher. 
(Condition II.E.2)
     Water sprays installed, operated, and maintained 
continuously (except as provided by the excess emission rule, A.A.C. 
R18-2-306 and 310) during the times of operation of the conveyor 
systems, transfer points, process equipment, and storage piles at the 
stacker discharge points. (Condition II.E.3)
     Baghouse installed and operated on the secondary crusher 
and associated vibrating screen. (Condition II.G.1)
     A weight rate of mined rock (waste rock and ore combined) 
shall not exceed 125,000 tons per 24-hour calendar day and 29 million 
tons per year. (Condition III.A)
     Burn only diesel no. 2 fuel with a sulfur content of less 
than 0.05 percent in the SX/EW tankhouse boiler and backup generator 
and the leach pad backup generator. (Condition II, Boiler and Generator 
Emissions, C.1)
     An ambient PM10 monitor installed, near the 
boundary of the mining activity in the general direction of the 
Superstition Wilderness, operated on an every-sixth-day schedule, and 
maintained in accordance with applicable manufacturer's instructions, 
EPA handbooks, and federal requirements (Condition IV.A).

    Dated: July 22, 1997.
Charles R. Bazan,
Forest Supervisor.
[FR Doc. 97-20010 Filed 1-29-97; 8:45 am]
BILLING CODE 3410-01-M