UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION III

1650 Arch Street

Philadelphia, Virginia  19103

Date:	    July 24, 2008										

Subject:  Revision to Virginia(s SIP 					         

    NOx SIP Call emissions reductions from IC engines and cement kilns

    Technical Support Document

     /s/  

From:     Marilyn Powers, Environmental Engineer

 	    Air Quality Planning Branch (3AP21)

To:	    File

 

Reviewed by:  _/s/______________________________

Cristina Fernandez, Branch Chief

Air Quality Planning Branch (3AP21)	

I.  Background

A.  Introduction

The Environmental Protection Agency (EPA) issued the Nitrogen Oxides
(NOx) SIP Call (63 FR 57356, October 27, 1998) to require 22 Eastern
states and the District of Columbia to reduce specified amounts of one
of the main precursors of ground-level ozone, NOx, in order to reduce
ozone that is transported across State boundaries.  EPA found that the
sources in these states emit NOx in amounts that contribute
significantly to nonattainment of the 1-hour ozone national ambient air
quality standard (NAAQS) in downwind states.  In the NOx SIP Call, the
amount of reductions required by states were calculated based on
application of available, highly cost-effective controls on certain
source categories of NOx.  These source categories included electric
generating units (EGUs), large non-EGUs, large natural gas internal
combustion engines, and large cement kilns.  EPA determined state
budgets based on controlling these sources by the specified amounts.  In
the NOx SIP Call, EPA established a model cap and trade rule that States
had the option to adopt in order to participate in the EPA-administered
trading program.

The NOx SIP Call (including the Technical Amendments to the 2007 EGU
budgets (64 FR 26298, May 14, 1999 and 65 FR 11222, March 2, 2000)) was
challenged by a number of state, industry, and labor groups.  A detailed
background of the NOx SIP Call, including the court decisions that were
made in response to challenges to the rule and impacts of the court
decisions on certain aspects of the rule may be found in EPA(s
rulemaking dated April 21, 2004 (69 FR 21604) entitled Interstate Ozone
Transport:  Response to Court Decisions on the NOx SIP Call, NOx SIP
Call Technical Amendments, and Section 126 Rules.  Many of the decisions
that were made by the court pertained to specific NOx SIP Call states
and to other areas of the NOx SIP Call that did not affect Virginia. The
portions of the April 21, 2004 rulemaking pertaining to Virginia(s
obligations under Phase II of the NOx SIP Call are included herein to
provide a background on the State(s requirements. 

On March 3, 2000, the DC Circuit Court issued its decision on the NOx
SIP Call.  It ruled largely in favor of EPA in support of its
requirements under the 1-hour ozone NAAQS, but in part ruled against EPA
on several issues. The portions of the NOx SIP Call that were upheld by
the Court were termed Phase I of the rule, and, with the exception of
the remand of the EGU growth factors used in the NOx SIP Call and the
requirements for the 8-hour ozone NAAQS (which EPA stayed due to
uncertainty created by the court rulings), the other portions that were
remanded for further rulemaking were finalized on April 21, 2004 and
termed Phase II of the rule.  The rulings against EPA included two areas
of the NOx SIP Call that were remanded and vacated and two areas in
which EPA was found to have failed to provide adequate notice of changes
in the rule.  In the latter case, the rulings included a failure to
provide adequate notice of the change in the definition of EGU as
applied to cogeneration units that supply electricity to a utility power
distribution system for sale in certain specified amounts, and a failure
to provide adequate notice of the change in control level EPA assumed
for large stationary internal combustion (IC) engines, both of which
were remanded to EPA for further rulemaking.

The two rulings pertaining to inadequate notice potentially required
additional adjustments to States( approved Phase I budgets to
incorporate the changed definition of cogeneration units, and required
additional reductions for states that had not yet met the Phase II
incremental reductions (some states chose to meet all their NOx SIP Call
obligations as part of their original Phase I rule). 

B.  EPA requirements

1.  Large Stationary Internal Combustion Engines

The April 21, 2004 rule finalized specific changes to the definition of
EGUs as applied to cogeneration units, finalized the control levels
assumed for large stationary IC engines subject to the NOx SIP Call,
adjusted states' total budgets (where necessary) to reflect these
changes, established a SIP submittal date of April 1, 2005 for States to
address the Phase II portion of the budget, and set a compliance date of
May 1, 2007 for reductions to meet Phase II of the NOx SIP Call.  As a
result of these changes, States are required to achieve an incremental
reduction of NOx emissions, that, added to their Phase I reductions,
would achieve the total required reductions needed to fully meet the NOx
SIP Call.  

The large stationary IC engines that comprise states’ Phase II NOx
SIP Call inventory are those engines that emitted more than 1 ton of NOx
per average ozone season day during the 1995 baseline ozone season.  The
amount of Phase II reductions required to be made by states is based on
controlling IC engines to the following levels, which were determined by
EPA to be highly cost effective:

	

-   For lean burn engines, 82 percent reduction

-   For rich-burn engines, 90 percent reduction

-   For diesel and dual fuel engines, 90 percent reduction

In Phase II, each state's total budget was adjusted downward to reflect
the additional reductions that correspond to these control levels as
applied to the engines in the NOx SIP Call inventory.  States have
flexibility in how to achieve the additional reductions, however they
must adopt rules that will, by the start of the 2007 ozone season,
achieve this incremental reduction, and submit the rules to EPA as a SIP
revision.

	

Virginia's NOx budget trading program (Phase I) under the NOx SIP Call
was approved as part of the Virginia SIP on July 8, 2003 (68 FR 40520),
with the exception of  its flow control provision, which was
conditionally approved.  The conditional approval was converted to a
full approval on August 25, 2005 (69 FR 52174).  The Phase II change to
the definition of cogeneration units did not affect the Phase I budget
previously established for Virginia and therefore will not be discussed
in any detail here, but a full discussion may be found in the April 21,
2005 rulemaking.  In order to meet its NOx SIP Call Phase II
obligations, the Commonwealth is required only to achieve the
incremental reductions that EPA calculated based on controlling large IC
engines to prescribed levels.  

Attachment 1 shows the 1995 NOx SIP Call Phase II inventory for each
affected source in Virginia.  EPA determined that Virginia’s Phase II
inventory included 17 IC engines, located at four sources.  The engines
are lean burn engines, and therefore must achieve at least an 82 percent
reduction.  Applying a 0.98 percent growth factor determined by EPA as
part of the NOx SIP Call, the projected 2007 uncontrolled inventory from
these engines total 4,077 tons of NOx. The total required reduction is
therefore 3,343 tons of NOx (82 percent of 4,077 tons).  A summary of
the reduction requirement by facility is shown in Table 1 below.

Table 1:  NOx SIP Call Phase II Inventory in Virginia

Station No.	Location	1995 baseline, tons	Growth Factor	2007 Uncontrolled
NOx, tons	% Required Reduction	Required Reduction, tons

165	Chatham	   201.8223	0.98	  197.7859	82%	   162.1844

170	Appomattox	2,691.7290	0.98	2,637.8944	82%	2,163.0734

175	Scottsville	1,107.8730	0.98	1,085.7156	82%	   890.2867

180	Unionville	   158.6610	0.98	   155.4878	82%	   127.5000

Total

4,160.0853

4,076.8836

3,343.0445



      

2.  Large Cement Kilns

	As part of the NOx SIP Call, States were also required to reduce NOx
emissions from cement manufacturing in an amount equivalent to that
achieved by applying highly cost effective controls to cement kilns that
emitted more than 1 ton of NOx per day during the 1995 ozone season. 
Highly cost effective controls on cement kilns were determined by EPA to
be equivalent to a 30 percent reduction.  In the NOx SIP Call, EPA cited
its peer reviewed analysis, ``EPA's Alternative Control Techniques
(ACT)'' (EPA-453/R-94-004, March 1994) as demonstrating that
cost-effective controls in the form of low-NOx burners and mid-kiln
firing are available to the cement kiln industry and can achieve a 30
percent reduction from uncontrolled levels of emissions.  Consistent
with this analysis, the federal implementation plan (FIP) for the NOx
SIP Call required installation and operation of low-NOx burners,
mid-kiln firing, or ``alternative control techniques,'' subject to
approval by EPA, that achieve at least the same 30 percent emissions
decrease as low-NOx burners or mid-kiln firing (63 FR 56416, October
21,1998).  EPA has previously approved into other States’ SIPs,
revisions that addressed reductions from this source category that
simply requires either low NOx burners or mid-kiln firing to be
installed on subject kilns.

	The 1995 EPA inventory for cement kilns in Virginia included four long
dry kilns and one preheater kiln, see Attachment 2.  In the notice of
proposed rulemaking for Virginia’s NOx budget trading program (67 FR
68544, November 12, 2002), it is noted that Virginia must still submit
SIP revisions to address any additional emission reductions required to
meet the Commonwealth's overall emissions budget, including cement
kilns.  

II.  Description of Revision

A. Description of Submittals

1.  Large Stationary IC Engines

The change to the definition of cogeneration units did not affect the
Phase I budget previously established for Virginia and will not be
discussed in any detail here, but, as noted above, can be found in the
April 21, 2004 rulemaking.  In order to fully meet its Phase II NOx SIP
Call obligations, the State was required to achieve the incremental
reductions that EPA calculated based on controlling IC engines to
prescribed levels.  

VADEQ determined that one company, Transcontinental Gas Pipe Line
Corporation (Transco), owns all of the potentially affected sources in
the State.  Transco is an interstate natural gas transmission company
having six stations located in Virginia.  VADEQ chose to require
Virginia’s Phase II emission reductions to come from 19 natural
gas-fired engines located at four stations (17 of the engines are in
EPA’s inventory).  To implement the reductions required under Phase
II, Virginia chose to issue federally enforceable state operating
permits for each of the Transco facilities.  VADEQ submitted the permits
as separate SIP revisions on the following dates:

February 26, 2007 SIP revision – Transco Station 165, Pittsylvania
County

March 5, 2007 SIP revision  -  Transco Station 170, Appomattox County

March 12, 2007 SIP revision -  Transco Station 175, Fluvanna County

March 19, 2007 SIP revision -  Transco Station 180, Orange County

2.  Cement Manufacturing

Virginia chose to modify an existing State operating permit to implement
the required Phase I NOx emission reductions from its affected cement
kilns.  On August 8, 2007, the State submitted a SIP revision that
consisted of a federally enforceable Stationary Source Permit to Operate
for Roanoke Cement Company located in Botetourt County.  The facility
currently includes one preheater/precalciner cement kiln with a capacity
of 550 MMbtu/hr and a permitted annual production rate of 1,300,000 tons
of clinker per year.

B.  EPA analysis of large stationary IC engine submittal

VADEQ’s submittals are comprised of federally enforceable state
operating permits containing terms and conditions for the control of
emissions of NOx from the affected IC engines at each station, as well
as a demonstration to show that Virginia is meeting an 82 percent
reduction at each station.  The permits have a compliance date of May 1,
2007, and include definitions, applicability, parametric monitoring
requirements, operating requirements, testing, reporting, and
recordkeeping requirements, as well as other general conditions and
requirements to ensure the terms of the permit are met.  

Virginia chose to apply an 82 percent NOx emission reduction to 19
engines at four Transco stations by limiting each affected engine’s
emission rate during the ozone season, and, for Station # 175, limiting
the total number of hours of operation during the ozone season.  The
permitted emission limits at each station is summarized below:

Table 2:  Permitted Emission Limits at Transco Stations

Transco Station	Affected Unit ID	Ozone Season NOx Emission Rate (lb/hr)
Ozone Season NOx Emissions Limit, tons (NOx emission rate times 
permitted operating hours)	Total Ozone Season Emissions at each Station
Reductions at each Station (tons/ozone season)

#165	M/L 11	19.20	35.25	35.25	162.53

                                                                 Total
for Station #165	35	162.53

#170	M/L 1	19.29	35.42

117.79

	M/L 2	19.29	35.42

148.69

	M/L 3	19.29	35.42

178.95

	M/L 4	19.29	35.42

186.19

	M/L 5	19.29	35.42

193.47

	M/L 6	20.25	37.18

122.45

	M/L 7	20.25	37.18

205.29

	M/L 8	26.23	48.16

241.78

	M/L 9	26.23	48.16

213.49

	M/L 10	26.23	48.16

213.46

	M/L 11	42.44	77.92

342.50

                                                                Total
for Station  #170	474	2164.05

#175	M01	219.00 	48.7275

214.99

	M02	219.00 	48.7275

224.52

	M03	219.00 	48.7275

208.87

	M04	219.00 	48.7275

242.43

                                                                Total
for Station #175	195	890.80

#180	M/L 8	19.25	35.34

30.97

	M/L 10	19.25	35.34

29.19

	M/L 14	48.5	89.05

66.44

                                                                Total
for Station #180	160	126.6



To comply with the 82 percent reduction for Station #175, the permit
limits the emission rate and imposes a restriction on the hours of
operation for the four affected engines.  Beginning May 1, 2007, the
affected engines are limited to a total of 1780 hours of operation per
ozone season.   The permit includes periodic monitoring and
recordkeeping to assure compliance with the emission limits set forth in
the permit.  A unit operating less than 45 hours per ozone season is
required to maintain records to document the hours of operation,
however, a unit operating at or more than 45 hours must be tested either
in accordance with Method 7 or 7E, or with a portable analyzer after the
end of the ozone season but prior to October 30.  A request to increase
the hours of operation of the facility above the limit will require
installation of low emission combustion technology on each unit to
ensure compliance with the ozone season NOx tonnage limit. 

Units at Stations #165, 170 and 180 may operate 3672 hours (the entire
ozone season), and are required to have a Parametric Monitoring Systems
(PMS) installed prior to May 1, 2007 to measure and record operating
performance indicators for NOx emissions.  Prior to May 1, 2007, a
minimum of nine initial emissions test runs are required at each engine
to establish a correlation between the engine operating parameters and
the NOx emission rate limit.  Once per ozone season beginning in 2008,
testing with a portable analyzer is required to demonstrate the validity
of the parametric monitoring and compliance with the emission
limitations set forth in the permit.  If any engine is changed in a
manner that results in significant changes in the parameters established
during the initial test runs, re-testing must be performed to
re-establish the correlation between parameters and the NOx emission
rate limit.

The initial emissions testing are required using Reference Method 7 or
7E to determine compliance with the ozone season limits. For each
facility, Transco is required to keep records and submit annual reports
to VADEQ documenting the total NOx emissions (in tons) from May 1
through September 30 of each year, as well as the percent utilization at
Stations 170, 175, and 180.

  SEQ CHAPTER \h \r 1 Virginia’s incremental budget demonstration
comprised of 19 large natural gas-fired IC engines that are subject to
Phase II is consistent with the reductions required, as shown in EPA’s
NOx SIP Call Engine Inventory.  Application of 82 percent reductions
from the uncontrolled 2007 base case results in an incremental reduction
of 3343 tons of NOx emissions in Virginia. EPA has determined that an
additional reduction of 3343 tons of NOx satisfies Virginia’s
requirements under Phase II of the NOx SIP Call, and that this amount
appropriately adjusts the incremental reduction specified in the April
21, 2004 rulemaking.   

C.  EPA Analysis of Cement Kiln Submittal

	VADEQ’s August 8, 2007 submittal is comprised of an amended Roanoke
Cement Company federally enforceable State operating permit and a
demonstration that the NOx reductions at this facility are meeting the
requirements of the NOx SIP Call.  

On June 18, 2007, VADEQ approved a modification to the operating permit
for Roanoke Cement.  The operating permit modification included language
that this permit also implements the requirements for cement
manufacturing mandated by Phase I of the NOx SIP Call (in addition to
the RACT requirements for this source).  The permit requires
installation of low NOx burners, records of annual throughput and
consumption of coal and fuel oil, and continuous emissions monitoring of
NOx from Kiln 5.

VADEQ provided information that in 1996, the facility underwent a major
modification and received a PSD permit for the modernization of the
plant.  As part of the modification, Kilns 1 through 4 (which were long,
dry kilns) were retired, and Kiln 5 (which was a preheater kiln) was
reconfigured as a preheater/precalciner kiln designed to handle the
capacity of the five kilns. In addition, the facility, as a result of
its Early Action Compact (EAC) for 8-hour ozone, installed low NOx
burners in 2006 as Reasonably Available Control Technology (RACT)
requirements for the kiln, see Attachment 3.  An EAC allows an area to
submit an enforceable SIP outlining the steps it will take to maintain
compliance with the 8-hour ozone standard to defer a potential
non-attainment designation until a later date.  Installation of RACT is
one of the requirements of Virginia’s EAC.  The permit required
installation of low NOx burners after the first scheduled plant shutdown
after November 15, 2005 but no later than June 1, 2006 and required a
reduction of NOx generation by ten percent.  

	As indicated above, installation of low NOx burners is one of the
options identified by EPA as available to the cement manufacturing
industry to achieve NOx emission reductions of  30 percent.  However, to
show that the reconfiguration of the preheater kiln is reducing NOx
emissions by at least 30 percent, VADEQ submitted a demonstration based
on evaluation of the thermal efficiency of the kiln to assess emission
rates for the preheater/precalciner process.  Thermal efficiency is
important because NOx emissions from these systems are proportional to
fuel usage.  Increasing thermal efficiency of a kiln will reduce the
amount of NOx emitted per ton of clinker produced.  The current
configuration is consistent with the Alternative Control Techniques
(ACT) document NOx Emissions from Cement Manufacturing
(EPA-453/R-94-004, March 1994) for minimizing NOx emissions and
maximizing thermal efficiency.  The State submission included
calculations of thermal efficiencies for both the long dry kilns and the
preheater/precalciner kiln between 1995 and 2005.  In this period the
thermal efficiency of the facility increased by 44.5 percent, which
indicates NOx reductions beyond 30 percent.  

	Alternatively, considering source classification code (SCC) emission
rates of 7.4 lb NOx per ton of clinker for the long dry kilns compared
to the 2005 monitored emission rate of 3.29 lb per ton of clinker for
the precalciner kiln, indicates NOx reductions of approximately 55%. 
Neither of these analyses takes into consideration the additional
reductions from the low NOx burners that were installed in 2006. 
Therefore, the overall reductions from uncontrolled 2007 emissions for
the facility would actually be greater than the State’s demonstration
would indicate.



III. Conclusion

The SIP revisions submitted by VADEQ meet the requirements of the NOx
SIP Call.  The federally enforceable state operating permits for the
stationary internal combustion engines include provisions to assure that
82 percent NOx emission reductions are achieved.  The State has
demonstrated that it is meeting the reduction requirements for cement
manufacturing, and the federally enforceable State operating permit for
the kiln has been revised to indicate that the preheater/precalciner
kiln with low NOx burners implements the requirements of the NOx SIP
Call. 

 

 IV.  Recommendation

The SIP revisions meet Virginia’s remaining obligations under the NOx
SIP Call and strengthen the Virginia SIP.  It is recommended that a
Notice of Proposed Rulemaking be published proposing approval of
Virginia(s SIP revisions for NOx emission reductions from large
stationary internal combustion engines to meet Phase II of the NOx SIP
Call, and NOx emission reductions from cement manufacturing to comply
with the NOx SIP Call requirements.

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