[Federal Register Volume 85, Number 131 (Wednesday, July 8, 2020)]
[Proposed Rules]
[Pages 40951-40958]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-14360]


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

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R06-OAR-2018-0856; FRL-10011-09-Region 6]


Air Plan Approval; New Mexico; Repeal of State Regulations for 
Particulate Matter for Lime Manufacturing Plants

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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

SUMMARY: Pursuant to the Federal Clean Air Act (CAA or the Act), the 
Environmental Protection Agency (EPA) is proposing to approve a New 
Mexico State Implementation Plan (SIP) revision for the repeal of State 
regulations titled 20.2.20 NMAC (Title 20: Environmental Protection, 
Chapter 2: Air Quality (Statewide), Part 20: Lime Manufacturing 
Plants--Particulate Matter of the New Mexico Administrative Code) that 
cover particulate matter emission standards for lime manufacturing 
plants and lime hydrators in the State of New Mexico. EPA is proposing 
to approve the repeal of the regulations based on the CAA section 
110(l) demonstration contained in the New Mexico submittal, which 
provides that the SIP revision will not interfere with attainment and 
maintenance of the NAAQS or any other CAA requirement.

DATES: Written comments must be received on or before August 7, 2020.

ADDRESSES: Submit your comments, identified by Docket No. EPA-R06-OAR-
2018-0856, at https://www.regulations.gov or via email to ruan-lei.karolina@epa.gov. Follow the online instructions for submitting 
comments. Once submitted, comments cannot be edited or removed from 
Regulations.gov. The EPA may publish any comment received to its public 
docket. Do not submit electronically any information you consider to be 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Multimedia submissions (audio, 
video, etc.) must be accompanied by a written comment. The written 
comment is considered the official comment and should include 
discussion of all points you wish to make. The EPA will generally not 
consider comments or comment contents located outside of the primary 
submission (i.e. on the web, cloud, or other file sharing system). For 
additional submission methods, please contact Ms. Karolina Ruan Lei, 
(214) 665-7346, ruan-lei.karolina@epa.gov. For the full EPA public 
comment policy, information about CBI or multimedia submissions, and 
general guidance on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.
    Docket: The index to the docket for this action is available 
electronically at www.regulations.gov. While all documents in the 
docket are listed in the index, some information may not be publicly 
available due to docket file size restrictions or content (e.g., CBI).

FOR FURTHER INFORMATION CONTACT: Ms. Karolina Ruan Lei, (214) 665-7346, 
ruan-lei.karolina@epa.gov. Out of an abundance of caution for members 
of the public and our staff, the EPA Region 6 office will be closed to 
the public to reduce the risk of transmitting COVID-19. We encourage 
the public to submit comments via https://www.regulations.gov, as there 
will be a delay in processing mail and no courier or hand deliveries 
will be accepted. Please call or email the contact listed above if you 
need alternative access to material indexed but not provided in the 
docket.

SUPPLEMENTARY INFORMATION: Throughout this document wherever ``we,'' 
``us,'' or ``our'' is used, we mean the EPA.

Table of Contents

I. Background
    A. Clean Air Act Section 110(l)
    B. State Implementation Plans (SIPs)
    C. The National Ambient Air Quality Standards (NAAQS)
    D. History of Reviews of the NAAQS for Particulate Matter
II. New Mexico's Submittal
    A. The Regulation Proposed for Repeal

[[Page 40952]]

    B. Particulate Matter Designated Areas in New Mexico
    C. Affected Facilities
III. The EPA's Evaluation of the State's Submittal and 
Noninterference Demonstration
    A. Potential Impact on Emissions
    B. Air Quality Modeling Demonstration for Lhoist North America
    C. Air Monitoring Data for New Mexico
    D. Summary of EPA's Evaluation
IV. Proposed Action
V. Statutory and Executive Order Reviews

I. Background

A. Clean Air Act Section 110(l)

    Section 110(l) of the Clean Air Act (CAA) provides that ``. . . The 
Administrator shall not approve a revision of a plan if the revision 
would interfere with any applicable requirement concerning attainment 
and reasonable further progress (as defined in [CAA section 171]) or 
any other applicable requirement of [the CAA].'' 42 U.S.C. 7410(l). 
Section 110(l) applies to all requirements of the CAA and to all areas 
of the country, whether attainment, nonattainment, unclassifiable or 
maintenance for one or more of the six criteria pollutants. Section 
110(l) applies to all NAAQS that are in effect, including those for 
which SIP submissions have not been made and addresses any interference 
with CAA requirements that would occur as a result from a SIP revision. 
In general, the level of rigor needed for any CAA section 110(l) 
demonstration will vary depending on the nature of the revision.
    Additionally, a state may substitute equivalent emissions 
reductions to compensate for any change to a plan to ensure actual 
emissions to the air are not increased and thus preserve status quo air 
quality. ``Equivalent'' emissions reductions are reductions that are 
equal to or greater than those reductions achieved by the control 
measure approved into the plan. To show that compensating emissions 
reductions are equivalent, adequate justification must be provided. The 
compensating, equivalent reductions should represent actual emissions 
reductions achieved in a contemporaneous time frame to the change of 
the existing control measure in order to preserve the status quo air 
quality. If the status quo is preserved, noninterference is 
demonstrated. In addition to being contemporaneous, the equivalent 
emissions reductions should also be permanent, enforceable, 
quantifiable, and surplus.
    Each noninterference demonstration submitted by a state requesting 
a SIP revision is evaluated on a case-by-case basis, considering the 
circumstances of the revision. EPA may approve a noninterference 
demonstration based on an evaluation of the SIP revision on air quality 
and/or the information provided in the noninterference demonstration.
    Some control measures may not be removed from a SIP even if doing 
so would not interfere with the CAA's air quality goals. These measures 
are often referred to as ``mandatory'' measures because the CAA 
requires that they be included in the SIP for an area based on the 
area's designation status and classification. Measures not tied to an 
area's classification and not mandated by the CAA are often referred to 
as ``discretionary'' measures. States can remove discretionary measures 
from an attainment, nonattainment or maintenance plan. However, a 
section 110(l) demonstration of noninterference would still be 
required.

B. State Implementation Plans (SIPs)

    A SIP is a set of statutes, air pollution regulations, control 
strategies, other means or techniques, and technical analyses developed 
by the state to ensure that the state meets the NAAQS. The SIP is 
required by section 110 and other provisions of the CAA. These SIPs can 
be extensive, containing state regulations or other enforceable 
documents and supporting information such as emissions inventories, 
monitoring networks, and modeling demonstrations. Each state must 
submit these regulations and control strategies to EPA for approval and 
incorporation into the federally enforceable SIP. Each federally 
approved SIP protects air quality primarily by addressing air pollution 
at its point of origin.

C. The National Ambient Air Quality Standards (NAAQS)

    Section 108 of the CAA requires EPA to establish NAAQS for 
pollutants that ``may reasonably be anticipated to endanger public 
health and welfare,'' and to develop a primary and secondary standard 
for each NAAQS. The primary standard is designed to protect human 
health with an adequate margin of safety, and the secondary standard is 
designed to protect public welfare and the environment. EPA has set 
NAAQS for six common air pollutants, referred to as criteria 
pollutants. These pollutants are: Carbon monoxide, lead, nitrogen 
dioxide, ozone, particulate matter, and sulfur dioxide. These standards 
present state and local governments with the minimum air quality levels 
they must meet to comply with the CAA. Additionally, these standards 
provide information to residents of the United States about the quality 
of the air in their communities.

D. History of Reviews of the NAAQS for Particulate Matter

    Section 109 of the CAA requires EPA to complete a thorough review 
of the NAAQS every five years and make such revisions in such criteria 
and standards as may be appropriate. On April 30, 1971, EPA promulgated 
the first NAAQS for particulate matter with the indicator set to total 
suspended particulate (TSP) (36 FR 8186). TSP was measured by the EPA 
reference method in 40 CFR part 50, Appendix B. The primary TSP 
standards were set at 260 micrograms per cubic meter of air ([mu]g/
m\3\) averaged over a 24-hour period, not to be exceeded more than once 
per year, and 75 [mu]g/m\3\ annual geometric mean, while the secondary 
TSP standards were set to 150 [mu]g/m\3\ for the 24-hour average and 60 
[mu]g/m\3\ for the annual mean.
    On July 1, 1987, the EPA published revisions to the NAAQS for 
particulate matter (52 FR 24634). The principle revisions to the 1971 
NAAQS included replacing TSP as the indicator for the ambient standards 
with a new indicator that includes particles with an aerodynamic 
diameter less than or equal to a nominal 10 [mu]m (PM10, or 
coarse particulate matter), replacing the 24-hour primary TSP standard 
with a 24-hour PM10 standard of 150 [mu]g/m\3\, replacing 
the annual primary TSP standard with an annual PM10 standard 
of 50 [mu]g/m\3\, and replacing the secondary TSP standard with 24-hour 
and annual PM10 standards identical in all respects to the 
primary standards.
    On July 18, 1997, the EPA promulgated a new NAAQS for fine 
particulate matter (PM2.5), which were defined as particles 
with an aerodynamic diameter less than or equal to a nominal 2.5 [mu]m 
(62 FR 38652). EPA promulgated a 24-hour and an annual standard for 
PM2.5. For the 1997 particulate matter NAAQS, the annual 
PM2.5 standard was set to 15 [mu]g/m\3\ and the 24-hour 
standard was set to 65 [mu]g/m\3\. On October 17, 2006, EPA published 
revised standards for particulate matter (71 FR 61144). For 
PM2.5, the annual standard of 15 [mu]g/m\3\ was retained, 
and the 24-hour standard was revised to 35 [mu]g/m\3\. For 
PM10, the annual standard of 50 [mu]g/m\3\ was revoked, 
while the 24-hour standard of 150 [mu]g/m\3\ was retained. On January 
15, 2013, EPA promulgated a new NAAQS for PM2.5 (78 FR 
3086). The newly promulgated primary annual PM2.5 standard 
was set to 12 [mu]g/m\3\, while the remainder of the standards were 
retained. The secondary annual PM2.5 standard was retained 
at 15 [mu]g/m\3\, the primary and secondary 24-hour standards were 
retained at 35 [mu]g/m\3\, the

[[Page 40953]]

PM10 primary and secondary 24-hour standards were retained 
at 150 [mu]g/m\3\.\1\
---------------------------------------------------------------------------

    \1\ See https://www3.epa.gov/ttn/naaqs/standards/pm/s_pm_history.html for a table of the history of the particulate 
matter NAAQS. The particulate matter NAAQS can also be found at 40 
CFR part 50.
---------------------------------------------------------------------------

II. New Mexico's Submittal

    On February 13, 2019, the New Mexico Environment Department (NMED) 
submitted a SIP revision for the repeal of 20.2.20 NMAC, certifying 
that the State of New Mexico has evaluated its air programs and the New 
Mexico SIP and found that the current federal and state regulations are 
sufficient to meet CAA requirements after the repeal of 20.2.20 NMAC. 
The submittal includes a noninterference demonstration, which contains 
information regarding allowable emissions and a modeling demonstration 
showing that the repeal will not interfere with attainment or 
maintenance of the NAAQS or any other applicable requirement of the 
Act. EPA has evaluated NMED's noninterference demonstration and 
proposes to conclude that approval of the revision will not interfere 
with attainment or maintenance of the NAAQS or any other applicable CAA 
requirement. The Technical Support Document (TSD), found in the docket 
for this action, provides additional details of certain aspects of the 
section 110(l) noninterference demonstration and EPA's evaluation that 
are not included in this notice.

A. The Regulation Proposed for Repeal

    The regulation proposed for repeal in New Mexico's February 13, 
2019, submittal is Title 20, Chapter 2, Part 20, of the NMAC (20.2.20 
NMAC, Lime Manufacturing Plants--Particulate Matter or Part 20), which 
covers particulate matter emissions from lime manufacturing plants and 
lime hydrators in New Mexico, excluding Albuquerque-Bernalillo County. 
Part 20 of 20.2 NMAC was first adopted by the New Mexico Environmental 
Improvement Board (EIB) as the Air Quality Control Regulation 509 on 
November 15, 1978, and was approved by EPA and adopted into the New 
Mexico SIP on April 10, 1980 (45 FR 24460). Since its promulgation, 
Part 20 has been reformatted twice, but no substantive changes were 
made (62 FR 50514, September 26, 1997).
    Part 20 was adopted to establish control measures to address 
potential exceedances of the TSP NAAQS in an area near Hurley, New 
Mexico, located in Grant County. That portion of Grant County was 
designated as a nonattainment area for TSP, and the State was required 
to submit a plan to meet CAA Part D requirements for the attainment and 
maintenance of the 1971 TSP NAAQS (43 FR 8962, March 3, 1978). Part 20 
incorporated the provisions of 40 CFR part 60, subpart HH, Standards of 
Performance for Lime Manufacturing Plants (NSPS Subpart HH), 
promulgated by the EPA on March 7, 1978, (43 FR 9452). The TSP NAAQS 
and the TSP area designations are no longer in place (61 FR 53639, 
October 15, 1996). As discussed in a previous section, the TSP NAAQS 
were replaced by the PM10 NAAQS. NSPS Subpart HH was also 
revised on April 26, 1984, with the particulate matter emission 
standards becoming less stringent (49 FR 18076), but New Mexico did not 
revise its SIP to incorporate these changes. The 1984 revision of NSPS 
Subpart HH eliminated the performance standards for lime hydrators that 
were in the original rule. Part 20 continues to be based on the 1978 
version of the NSPS Subpart HH.

B. Particulate Matter Designated Areas in New Mexico

    New Mexico has one particulate matter nonattainment area in 
Do[ntilde]a Ana County. The City of Anthony, New Mexico in Do[ntilde]a 
Ana County was designated a ``moderate'' nonattainment area for the 
1987 PM10 NAAQS (56 FR 56694, November 6, 1991). NMED 
determined that all point and area sources of PM10 in or 
affecting the area to be de minimis, except for unpaved roads, 
unvegetated and sparsely vegetated areas, and range lands. The paving 
of roads was determined to be economically infeasible, the enhancement 
of ground cover in the region to be technologically infeasible, and 
emissions from range lands to be nonanthropogenic (58 FR 18190, April 
8, 1993).\2\ This area is still impacted by blowing dust from high 
winds, and NMED is developing a dust mitigation plan for both 
Do[ntilde]a Ana and Luna counties, as required by EPA's national 
Exceptional Events Rule codified at 40 CFR 50.14 (81 FR 68216, October 
3, 2016). In addition to the dust mitigation plan, NMED is developing a 
fugitive dust rule that will be applicable in areas of the state 
requiring a mitigation plan in accordance with 40 CFR 51.930. The rest 
of the State of New Mexico is designated attainment/unclassifiable for 
PM10, and there are no areas designated nonattainment under 
the PM2.5 NAAQS (40 CFR 81.332).
---------------------------------------------------------------------------

    \2\ On September 9, 1993, the EPA granted approval of the 
Anthony, New Mexico, moderate nonattainment area PM10 
SIP, submitted November 8, 1991, including the waiver of the 
moderate area attainment date for Anthony, New Mexico (58 FR 47383).
---------------------------------------------------------------------------

    As mentioned in the previous section, there was a TSP nonattainment 
area based on the 1971 TSP NAAQS within Grant County, which covered a 
4.5-mile radius around the Kennecott Copper Smelter, located near the 
town of Hurley, New Mexico (44 FR 46895, August 9, 1979). Since then, 
the federal TSP standard has been revoked and the smelter has been 
closed.

C. Affected Facilities

    There is only one lime facility (Lhoist North America) in New 
Mexico, operating with a lime hydrator and no lime kiln, located in the 
City of Belen in Valencia County that is subject to Part 20. See Figure 
1 in the TSD for a map of New Mexico which portrays the locations of 
the Lhoist North America facility and the particulate matter 
nonattainment area. The Lhoist North America facility (``Lhoist Belen 
Chemical Lime Plant'') in Valencia County is shown to be a long 
distance (287 kilometers [km]) away from the only particulate matter 
nonattainment area in New Mexico, which is the PM10 
nonattainment area in Anthony, Do[ntilde]a Ana County. Lhoist impacts 
are negligible on the distant Anthony nonattainment area, and, as a 
point of reference, AERMOD \3\ (dispersion model typically used in 
PM10 modeling) is only used to model out to 50 km from the 
source. Likewise, because of the location of Lhoist in central New 
Mexico, Lhoist impacts on air quality in other states are negligible.
---------------------------------------------------------------------------

    \3\ AERMOD is the air quality dispersion model developed by 
Environmental Protection Agency (EPA), in conjunction with American 
Meteorological Society (AMS) to be used as the AMS/EPA Regulatory 
Model (AERMOD) promulgated by EPA in 2005 as the preferred 
regulatory dispersion model for predicting near-surface pollutant 
concentrations within 50 km of an emission source.
---------------------------------------------------------------------------

III. The EPA's Evaluation of the State's Submittal and Noninterference 
Demonstration

    The repeal of Part 20 eliminates measures for the control of 
particulate matter from lime manufacturing plants. While the rule was 
instituted to reduce TSP, we must consider the repeal's potential 
impact on attainment or maintenance of the current NAAQS for 
PM10 and PM2.5. The repeal will only potentially 
impact particulate matter emissions. Based upon evaluation of the 
permit, no increases in potential to emit of other criteria pollutants 
at the Lhoist facility are expected from the repeal of Part 20. The 
rule is considered a discretionary measure, as this term was discussed 
previously, because TSP

[[Page 40954]]

measures included in Part 20 are no longer tied to an area's 
classification and no longer mandated by the CAA, and therefore the 
control of lime manufacturing is not required to be included in the New 
Mexico SIP. Therefore, the rule may be repealed so long as a 
demonstration of non-interference is made.
    Section 110(l) prohibits EPA from approving a revision to the SIP 
if it would interfere with any applicable requirement concerning 
attainment and reasonable further progress (as defined in section 171), 
or any other applicable requirement of the Act. The repeal of this rule 
will not impact any other applicable requirement. For example, this 
measure was not part of New Mexico's SIP to address Regional Haze (77 
FR 70693, November 27, 2012; 79 FR 60985, October 9, 2014). In the 
following sections, we will address the repeal's potential impact on 
CAA requirements, including the attainment of the PM10 and 
PM2.5 NAAQS.

A. Potential Impact on Emissions

    While this rule was initially adopted to address multiple 
facilities, there is currently only one facility subject to Part 20 in 
the State of New Mexico. The one subject facility is owned by Lhoist 
North America of Arizona (Lhoist) and is located in the City of Belen, 
in Valencia County. Lhoist's Belen Chemical Lime Plant does not operate 
a lime kiln and only operates a lime hydrator. The facility receives 
quick lime (calcium oxide) and converts it to hydrated lime (calcium 
hydroxide) and is an emission source for PM10 and 
PM2.5. The Lhoist lime plant has a New Source Review permit 
with the State of New Mexico (Permit No. 1652 M2-R7) issued under the 
state's SIP-approved permitting program. NSPS Subpart HH and NESHAP 
Subpart AAAAA do not cover the Lhoist facility, as the facility does 
not operate a lime kiln. Permit provisions for the Lhoist facility, 
which include numerical emissions limitations reflected in pounds per 
hour (lbs/hr), will remain unchanged if Part 20 is repealed from the 
State SIP. These lbs/hr limits are consistent with the limit in Part 
20, which is a rate-based limit of 0.15 lbs/ton. NMED provided modeling 
based on the allowable emissions in the permit to show that the 
particulate matter NAAQS would remain protected. This modeling 
demonstration is discussed in a later section.
    The Lhoist facility has a minor New Source Review permit. State 
regulations at 20.2.72 NMAC, Construction Permits, (Part 72) have been 
incorporated into the New Mexico SIP and was most recently approved on 
March 11, 2013 (78 FR 15296). Under the SIP permitting rules, 
regardless of the repeal of Part 20, a permit is still required for the 
facility, as the particulate matter emissions from the lime hydrator 
are estimated to be greater than the 10 lbs/hr or 25 tons/year 
permitting thresholds prescribed under Part 72 for minor New Source 
Review. Additionally, a permit is required to limit emissions for quick 
lime and hydrated lime as those are considered toxic air pollutants 
that need to be specifically controlled as required under Part 72 
(20.2.72.200.A.(4), 400, 402, and 502 NMAC). If Lhoist decides to apply 
for a permit revision to remove the Part 20 requirements, Lhoist North 
America would have to show that their facility would still be able to 
comply with the NAAQS as required by their permit and Part 72. Permit 
Condition #l(f) of the Lhoist permit states that: ``Changes in plans, 
specifications, and other representations stated in the application 
documents shall not be made if they cause a change in the method of 
control of emissions or in the character of emissions, or will increase 
the discharge of emissions. Any such proposed changes shall be 
submitted as a revision or modification . . . of this permit.'' NMED 
stated in the submittal that should Lhoist apply for a permit revision 
in response to the repeal of Part 20 (e.g. to remove Permit Condition 
#l(e) which cites to Part 20), Part 72 still requires the applicant to 
show compliance with the NAAQS through modeling.
    Please see the State's submittal for this action for the complete 
text of the regulation proposed for repeal. Table 1 of the TSD provides 
a description and citations of the individual sections of Part 20, as 
well as applicable portions of the State and federal regulations for 
comparison purposes.
    The New Mexico rules at Part 20 cover both facilities with lime 
kilns and those with lime hydrators. Currently, there are no lime 
manufacturing facilities that operate lime kilns in New Mexico. New 
lime manufacturing facilities in New Mexico subject to the applicable 
requirements would be required to apply for a permit with enforceable 
emissions limits, pursuant to Part 72. Currently, the only facility 
subject to Part 20 is Lhoist North America, which operates a lime 
hydrator, but does not operate a lime kiln. Even with the repeal of 
Part 20, Lhoist North America will still be subject to Part 72.

B. Air Quality Modeling Demonstration for Lhoist North America

    As part of its noninterference demonstration, NMED submitted a 
modeling demonstration showing how the only lime facility in New Mexico 
subject to Part 20, Lhoist North America's Belen Chemical Lime Plant, 
does not interfere with attainment of the NAAQS at its full potential 
to emit. The facility is a baseline source for both PM10 and 
PM2.5 prevention of significant deterioration (PSD) 
increment.\4\ Therefore, most of the facility emissions do not consume 
increment (just emissions above the baseline emission rate), and the 
facility has minimal impacts on both Class I and Class II increment 
consumption.\5\ We are providing a brief summary of our analysis of New 
Mexico's modeling supporting this proposal; please see the TSD for this 
notice for our more detailed analysis and review.
---------------------------------------------------------------------------

    \4\ PSD increment consumption occurs when emissions increases 
occur after the major source baseline date for major sources (PSD 
sources) and after the minor source baseline date for minor sources. 
The Lhoist facility is a minor source (for PSD purposes) in Air 
Quality Control Region 152. Lhoist's facility was in place 
(constructed in 1995) and had emissions prior to the minor source 
baseline date for PM10 (March 26, 1997) and 
PM2.5 (February 11, 2013). Since the Lhoist facility 
emissions were in existence prior to the minor source baseline 
dates, only increases in Lhoist facility emissions above the 
emissions that were emitted at the time of the minor source baseline 
date would consume increment.
    \5\ Given the relatively small permitted emission rates and 
relatively low maximum modeled values (30-35% of the NAAQS for the 
permitted emission rates), small changes over baseline emission 
rates would not create increment consumption issues since the 
increment for PM10 (30 [mu]g/m\3\) is 20% of the 
PM10 NAAQS, the increment for 24-hour PM2.5 (9 
[mu]g/m\3\) is 26% of the 24-hour PM2.5 NAAQS and 
increment for annual PM2.5 (4 [mu]g/m\3\) is 33% of the 
annual PM2.5 NAAQS. As can be seen in Table 1 of this 
Federal Register action, Lhoist's maximum impacts from all permitted 
emissions are below the increment levels, so any smaller emission 
changes from the baseline emissions would be even lower and would 
not be near PSD increment levels.
---------------------------------------------------------------------------

    The modeling included in the SIP submittal for this action was 
performed in 2017. In the modeling, NMED used the most current version 
of AERMOD at the time (AERMOD version 16216) and modeled using 
meteorological data from 2013. NMED's modeled values are based on 
permitted allowable emissions for Lhoist so they represent the highest 
possible emissions allowed by their existing permit. Recent actual 
emissions are lower. NMED also included surrounding sources within 35 
km and used monitoring data to represent background concentrations 
which was added to the maximum design value model values. NMED's 
modeling indicated that the maximum modeled design values (with 
background

[[Page 40955]]

concentrations added) were below the NAAQS (see Table 1).
[GRAPHIC] [TIFF OMITTED] TP08JY20.001

    EPA has performed additional modeling as part of the review of the 
submitted SIP revision. We utilized the most recent version of AERMOD 
(version 19191 issued in 2019). NMED used one year of meteorology for 
their modeling analysis and the 2016 AERMOD version (which was the 
current AERMOD version when New Mexico performed the modeling in 2017). 
EPA performed additional modeling with the 2019 AERMOD (which is the 
current version) and five years of meteorological data to confirm 
NMED's conclusion that removal of the New Mexico lime regulations in 
Part 20 would not interfere with NAAQS and PSD increments. EPA's 
Guideline on Air Quality Models (40 CFR part 51, Appendix W) indicates 
that, when available, five consecutive years of meteorology should be 
utilized when performing AERMOD modeling. Using the same background 
monitoring data that NMED used in its submitted modeling demonstration, 
EPA's 5-year modeling results (see Table 2) resulted in similar values 
to NMED's 1-year modeling results. Specifically, EPA's modeling 
indicated that the maximum cumulative concentrations (from Lhoist and 
other modeled sources within 35 km) with monitored background 
concentrations added for the 24-hour PM10 concentration is 
58.9 [mu]g/m\3\ which is 39.3% of the PM10 24-hour NAAQS of 
150 [mu]g/m\3\; the maximum cumulative with monitored background added 
for PM2.5 24-hour is 23.3 [mu]g/m\3\ which is 66.6% of the 
PM2.5 24-hour NAAQS of 35 [mu]g/m\3\; and the maximum 
cumulative with monitored background added for PM2.5 Annual 
is 10.5 [mu]g/m\3\ which is 87.5% of the Annual PM2.5 NAAQS 
of 12 [mu]g/m\3\. EPA's modeling demonstrated that Lhoist 
contributions, using linear scaling, would allow for more than a 55% 
increase in emissions and still be below the annual and 24-hour 
PM2.5 NAAQS and 24-hour PM10 NAAQS. Even with the 
potential changes in emissions from the Lhoist facility that could 
occur below permitting thresholds, the changes would not be expected to 
exceed the 24-hour PM10 and PM2.5 NAAQS (annual 
and 24-hour). In addition, small changes in emissions would also 
trigger review pursuant to the existing permit limit discussed 
previously (Permit Condition #1(f)). Larger emission changes would 
require additional permitting including modeling to confirm that the 
NAAQS and PSD increments are not exceeded and the change in emissions 
would not interfere with NAAQS or PSD increments.

[[Page 40956]]

[GRAPHIC] [TIFF OMITTED] TP08JY20.002

    EPA's modeling results, like NMED's modeling results,\6\ 
demonstrate that: (1) Maximum impact levels near the Lhoist facility 
are below the NAAQS, and (2) the higher impacts from the facility are 
near the facility and quickly drop off to less than 50% of the maximum 
impact levels at a range of 300 meters or less from the facility. New 
Mexico modeled Lhoist's emissions with a 4 km square grid centered 
around Lhoist to determine the maximum distance from the Lhoist 
fenceline that Lhoist has a significant impact to confirm that the 
receptor grid captured all the area that Lhoist's emissions had a 
significant impact (the area where the Lhoist emissions model to be 
above the PSD Significant Impact Level [PSD SIL] and potentially have a 
significant impact on the 24-hour PM10, 24-hour 
PM2.5, or annual PM2.5 NAAQS). NMED and EPA then 
evaluated the modeling of the Lhoist facility and all other particulate 
matter sources within 35 km from Lhoist, added background monitoring 
values, and compared the results to the NAAQS and PSD increment. No 
areas within the modeled area (4 km square grid centered on Lhoist) 
were identified in this analysis that were above the PSD increment or 
that were near or above the NAAQS, including where Lhoist emissions 
contributed significantly to the maximum modeled design values near the 
Lhoist facility. Therefore, Lhoist emissions will not interfere with 
continued attainment of the NAAQS nor with PSD increment.
---------------------------------------------------------------------------

    \6\ See TSD for EPA's detailed analysis of NMED's modeling and 
modeling results.
---------------------------------------------------------------------------

C. Air Monitoring Data for New Mexico

    NMED and EPA have reviewed monitoring data to consider whether the 
repeal of the Part 20 rules could cause potential NAAQS attainment 
issues based on measured data. New Mexico's Statewide Air Quality 
Surveillance Network was approved into the New Mexico SIP by EPA on 
August 6, 1981 (46 FR 40005). New Mexico's air quality surveillance 
network undergoes recurrent annual review by EPA, as required by 40 CFR 
58.10. On July 9, 2019, NMED submitted its 2019 Annual Air Monitoring 
Network Plan (AMNP) that included plans for the particulate matter 
NAAQS. In our letter to the NMED dated October 31, 2019, we approved 
the 2019 New Mexico AMNP with comments, and in our comments, we stated 
that the NMED is currently meeting the network design requirements for 
ambient air quality monitoring for particulate matter. The NMED 
operates a network of six sites with PM10 State or Local Air 
Monitoring Stations (SLAMS) monitors, one site with a PM10 
Special Purpose Monitor station, and seven sites with a total of nine 
PM2.5 SLAMS monitors.
    NMED stated in its submittal that past monitoring data for New 
Mexico for years 2010-2015 show that all counties are well below the 
PM2.5 NAAQS, and except for Do[ntilde]a Ana County, are 
below the NAAQS for PM10 as well. Exceedances measured for 
this period for PM10 in Do[ntilde]a Ana, Luna and San Juan 
counties were all flagged by NMED in the EPA's Air Quality System as 
exceptional events (high winds or wildfire). As stated earlier in the 
notice, Anthony, New Mexico in Do[ntilde]a Ana County was designated 
nonattainment for the 1987 p.m.10 NAAQS. NMED concluded that 
since elevated PM10 levels in Do[ntilde]a Ana County are 
nonanthropogenic and not due to lime manufacturing or lime hydrators, 
they would be unaffected by the repeal of Part 20. We agree with NMED 
that the repeal of Part 20 will not affect ongoing efforts to reduce 
PM10 levels in Anthony, New Mexico.
    Since the SIP submission, additional monitoring data is available. 
In the following paragraphs, EPA evaluates the most recent monitoring 
data for New Mexico.
    Quality-assured and certified particulate matter monitoring data 
for years 2016-2018 contained the following design values for 
PM2.5 and PM10, shown in Table 3.\7\ Additional

[[Page 40957]]

information on the monitors is provided in the TSD.
---------------------------------------------------------------------------

    \7\ See docket for the 2016-2018 monitoring data containing the 
design values for New Mexico that has been retrieved from EPA's Air 
Quality System and has been quality-assured and certified by the 
EPA. The information taken from these reports and in these tables is 
intended for informational use only and does not constitute a 
regulatory determination by EPA as whether an area has attained a 
NAAQS.
    \8\ The level of the 2012 annual NAAQS for PM2.5 is 
12.0 [mu]g/m\3\. The design value for the annual PM2.5 
NAAQS is the 3-year average annual mean concentration.
    \9\ The level of the 2006 24-hour NAAQS for PM2.5 is 
35 [mu]g/m\3\. The design value for the 24-hour PM2.5 
NAAQS is the 3-year average 98th percentile concentration.
    \10\ The level of the 1987 24-hour NAAQS for PM10 is 
150 [mu]g/m\3\. The NAAQS metric for the PM10 NAAQS is 
the 3-year average expected number of exceedances. The standards are 
attained when the expected number of days per calendar year with a 
24-hour average concentration above 150 [mu]g/m\3\ is equal to or 
less than one.

                Table 3--2016-2018 Particulate Matter Design Value Concentrations for New Mexico
----------------------------------------------------------------------------------------------------------------
                                                                                              PM10 design value
                                                 PM2.5 design value    PM2.5 design value    (average estimated
               Location (county)                (annual, [mu]g/m\3\)    (24-hour, [mu]g/      exceedances) \10\
                                                         \8\                m\3\) \9\
----------------------------------------------------------------------------------------------------------------
Bernalillo....................................                   7.8                    20                   0.7
Do[ntilde]a Ana...............................                   8.3                    27                   2.1
Lea...........................................                   7.6                    16  ....................
Luna..........................................  ....................  ....................                     1
----------------------------------------------------------------------------------------------------------------

    Monitoring data for PM2.5 show that all of the listed 
New Mexico counties with monitors have design values well below the 
annual and 24-hour PM2.5 NAAQS for the years 2016-2018. 
Monitoring data for PM10 show that Bernalillo County and 
Luna County were at or below the annual PM10 NAAQS for the 
2018 design values for years 2016-2018. As a result, measured values of 
particulate matter indicate that repeal of Part 20 will not interfere 
with attainment of the NAAQS.

D. Summary of EPA's Evaluation

    The requirements of 20.2.20 NMAC are a discretionary requirement of 
the New Mexico SIP and not required to be included in the SIP. After 
evaluating the State's submittal, we propose to find that the removal 
of 20.2.20 NMAC from the New Mexico SIP will not interfere with any 
applicable requirement concerning attainment and reasonable further 
progress, or any other applicable requirement of the CAA. We base our 
finding on the following:
     This rule, while originally intended to apply to multiple 
sources, now only applies to one source.
     The one source is also governed by a permit issued under 
the SIP-approved permitting requirements of Part 72 that requires 
compliance with CAA requirements, including the NAAQS.
     Modeling that shows that this one source at its full 
potential to emit emissions will not cause an exceedance of the NAAQS 
or PSD increment.
     The nearest particulate matter nonattainment area is 287 
km away from this source, and its nonattainment issues are primarily 
caused by nonanthropogenic sources. Therefore, the one subject source 
will not have an impact on that area.
     Likewise, the one source is located centrally in New 
Mexico and will therefore have a negligible impact on any surrounding 
state's air quality.
     Finally, review of recent monitoring data does not 
indicate particulate matter nonattainment problems to which the source 
might contribute.
     There are no other applicable requirements, such as the 
New Mexico Regional Haze Plan, with which emissions from the source 
could interfere.
    If new sources or modification at the existing source occur, these 
changes will have to be approved under NMED's SIP-approved permitting 
program to ensure that the changes will not interfere with attainment 
and maintenance of the NAAQS.

IV. Proposed Action

    We are proposing to approve New Mexico's February 13, 2019, SIP 
submittal that provides modifications to State regulations and update 
the federally approved New Mexico SIP accordingly. The SIP revision, if 
approved by EPA, will remove 20.2.20 NMAC, Lime Manufacturing Plants--
Particulate Matter, from the New Mexico SIP, codified at 40 CFR part 
52, subpart GG, 52.1620, and we propose to find that such a revision 
will not adversely affect the attainment of applicable CAA 
requirements.

V. Incorporation by Reference

    In this document, the EPA is proposing to amend regulatory text 
that includes incorporation by reference. As described in the Proposed 
Action section above, the EPA is proposing to remove 20.2.20 NMAC from 
the New Mexico SIP, which is incorporated by reference in accordance 
with the requirements of 1 CFR part 51.

VI. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provisions of the Act and applicable 
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submissions, the EPA's role is to approve state choices, 
provided that they meet the criteria of the CAA. Accordingly, this 
action merely proposes to approve state law as meeting Federal 
requirements and does not impose additional requirements beyond those 
imposed by state law. For that reason, this action:
     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Orders 
12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 
2011);
     Is not an Executive Order 13771 (82 FR 9339, February 2, 
2017) regulatory action because SIP approvals are exempted under 
Executive Order 12866;
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);

[[Page 40958]]

     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because application of those requirements would be inconsistent 
with the CAA; and
     Does not provide EPA with the discretionary authority to 
address, as appropriate, disproportionate human health or environmental 
effects, using practicable and legally permissible methods, under 
Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, the SIP is not approved to apply on any Indian 
reservation land or in any other area where EPA or an Indian tribe has 
demonstrated that a tribe has jurisdiction. In those areas of Indian 
country, the proposed rule does not have tribal implications and will 
not impose substantial direct costs on tribal governments or preempt 
tribal law as specified by Executive Order 13175 (65 FR 67249, November 
9, 2000).

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Particulate matter.

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

    Dated: June 29, 2020.
Kenley McQueen,
Regional Administrator, Region 6.
[FR Doc. 2020-14360 Filed 7-7-20; 8:45 am]
BILLING CODE 6560-50-P


