U.S. ENVIRONMENTAL PROTECTION AGENCY 

REGION IX 

STATEMENT OF BASIS AND 

AMBIENT AIR QUALITY IMPACT REPORT 

ADDENDUM 

For a Clean Air Act 

Prevention of Significant Deterioration Permit 

Victorville 2 Hybrid Power Project 

PSD Permit Number SE 07-02 

March 2010 

 
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Proposed Prevention of Significant Deterioration (PSD) Permit 

Statement of Basis and Ambient Air Quality Impact Report 

Addendum 

VICTORVILLE 2 HYBRID POWER PROJECT 

 On June 6. 2008, EPA proposed a Prevention of Significant Deterioration (PSD) permit 

for the Victorville 2 Hybrid Power Project and published a public notice requesting comment on 

the permit in the Victorville Daily Press. EPA received two comment letters on July 7, 2008, one 

from Adams Broadwell Joseph & Cardozo (ABJC), on behalf of California Unions for Reliable 

Energy (CURE), and one from ENSR Corporation (ENSR), on behalf of the City of Victorville 

and Inland Energy. On October 7, 2008, ENSR withdrew its comment letter on the proposed 

permit, and on June 8, 2009, ABJC also withdrew its comment letter. EPA received no other 

comments regarding the proposed action and PSD permit. Because both comment letters were 

withdrawn, EPA has determined it is not necessary to respond comments in issuing the final PSD 

permit allowing construction of the facility. 

Before ABJC withdrew its comment letter, EPA changed its policy for evaluating 

particulate matter with a diameter of 2.5 microns or less (PM2.5). The proposed PSD permit 

relied on the provision of the May 16, 2008 final rule for PM2.5 (73 FR 28321) allowing the use 

of PM10 as a surrogate for PM2.5 for complete permit applications submitted before July 15, 

2008, known as the grandfathering provision. On February 10, 2009, Earthjustice, on behalf of 

the Natural Resources Defense Council and the Sierra Club, submitted a petition for 

reconsideration on four provisions of the May 2008 final PM2.5 rule, including the grandfathering 

provision. EPA granted a three-month administrative stay of the grandfathering provision, 

effective June 1, 2009 (74 FR 26098). On September 22, 2009, EPA issued a final rule 

extending the administrative stay an additional nine months, until June 22, 2010 (74 FR 48153). 

On February 11, 2010, EPA proposed to repeal the grandfathering provision from the PM2.5 new 

source review (NSR) implementation rule and confirmed the current stay on the grandfathering 

provision remains in effect through June 22, 2010 (75 FR 6827). 

EPA requested additional information from the applicant to evaluate if this change in 

regulatory policy would result in requiring any different conditions in the PSD permit. The 

BACT analysis and conditions are still appropriate for natural gas-fired power plants because the 

combustion of natural gas results in the formation of particulate matter that is exclusively PM2.5, 

therefore PM10 and PM2.5 are equivalent from natural gas-fired turbines. Therefore, the BACT 

determination and emission limits in the PSD permit for PM2.5 were unchanged, but the final 

permit was revised to refer to “PM2.5” rather than “PM10 as a surrogate for PM2.5”. This revision 

to require BACT for PM2.5 does not require an additional public comment period because this 

revision does not relax or significantly revise any of the original proposed permit conditions. 

The applicant also submitted modeling to demonstrate that PM2.5 emissions would not 

cause a violation of the NAAQS. For the PM2.5 modeling requirements for PSD, EPA has not 
yet established the significant impact levels (SILs). The SILs are used as a screening tool; 

applicants with emission impacts below the SILs are not required to conduct the cumulative 

impact analysis that includes the impacts of nearby sources. Because EPA has not yet 

established SILs for PM2.5, on December 29, 2009, AECOM submitted a cumulative modeling 

analysis for PM2.5. AECOM included emissions from the following nearby sources: High Desert 

Power Plant, AGC Glass Company, and TXI Riverside Cement. The modeling results 

determined that impacts of the Victorville 2 facility combined with the three major nearby 

sources would result in a cumulative impact of 14 μg/m3 (24-hour average) and 1.65 μg/m3

(annual average). Additionally, AECOM updated their background PM2.5 concentrations to use 

data from 2005 – 2007. AECOM used background values based on the highest 3-year average of 

the 98th percentiles (19 μg/m3 on a 24-hour average), and the highest 3-year average annual 

mean (10.1 μg/m3 on an annual average). Thus, the cumulative impact of Victorville 2 and 

nearby facilities, plus the background is 33 μg/m3

 (24-hour average) and 11.7 μg/m3 (annual 

average), which does not exceed the PM2.5 NAAQS of 35 μg/m3 (24-hour average) and 12 μg/m3

(annual average). Because AECOM made conservative assumptions in modeling the nearby 

sources and PM2.5 background, EPA has determined that the conditions in the PSD permit as 

proposed do not require revision. The PM2.5 modeling assumptions are conservative because 

AECOM modeled nearby sources (AGC Glass Company and TXI Riverside) using the 

conservative assumption that PM2.5 emissions are 100% of PM10 emissions. In addition, the 

background data from 2005-2007 also measures the impact from existing nearby sources (High 

Desert Power Plant, AGC Glass Company and TXI Riverside). 

The December 29, 2009 cumulative modeling analysis is available in the docket for this 

action (Docket ID # EPA-R09-OAR-2008-0765), and EPA has determined that an additional 

public comment period is not required because the permit conditions were not relaxed and the 

additional modeling analysis was submitted to comply with a more stringent modeling 

requirement for PM2.5. The results of the conservative modeling analysis show that Victorville 2 

will not cause or contribute to a violation of the PM2.5 NAAQS. Therefore, EPA is finalizing the 

PSD permit for Victorville 2 with the minor revisions listed above.