The State of New Hampshire 

Department of Environmental Services 

Mr. David Conroy, Chief 

Air Programs Branch 

Thomas S. Burack, Commissioner 

May 21,2015 

U.S. Environmental Protection Agency, Region I 

5 Post Office Square, Suite 100 

Boston, MA 02109-3912 

Re: Supplemental Information for Certification of Adequacy for 2010 Sulfur Dioxide 

Standard SIP Submittal (Infrastructure SIP) 

Dear Mr. Conroy: 

As Governor Hassan's designee, I am enclosing for your review and approval the 

requested supplemental information to New Hampshire's certification of adequacy for the 2010 

National Ambient Air Quality Standard (NAAQS) for sulfur dioxide (S02) which was submitted 

to the United States Environmental Protection Agency, Region I (EPA) on September 13,2013. 

This supplemental information certifies to the EPA that New Hampshire's State Implementation 

Plan (SIP) fulfills the "infrastructure" requirements established in paragraphs 11 O(a)(1) and (2) 

of the Clean Air Act (CAA). New Hampshire is also requesting a change in its priority region 

classification for S02 episode plans in accordance with 40 CFR 51.150. 

In order to approve New Hampshire's request to change to a Priority III region for S02 

episode plans in accordance with 40 CFR 51.150(£), EPA has requested that New Hampshire 

supplement its September 13, 2013 SIP submittal with the most recent three years of S02 

monitoring data (2012 through 2014). Table 1 below provides the requested annual S02 ambient 

concentrations in parts per million (ppm) data for the most recent three year period (2012 

through 2014) to supplement the S02 monitoring data previously submitted in the September 

2013 SIP. The data for 2012 and 2013 have been certified by the New Hampshire Department of 

Environmental Services, Air Resources Division (DES) and concurred on by EPA. All of the 

2014 data has been reviewed for accuracy and the DES has issued a certification letter to EPA. 

Based on the values presented in Table 1 and those contained in the September 13, 2013 

submittal, at no time was the 0.02 ppm Priority II S02 threshold reached anywhere in the state. 

www.des.nh.gov 

29 Hazen Drive • PO Box 95 • Concord, NH 03302-0095 

(603) 271-3503 • TDD Access: Relay NH 1-800-735-2964 .... J 

!_)()/! @Ai'ijliiwl 
Mr. David Conroy, Air Programs Branch Chief 

(fypplememal In/ormation - 0 I 0 Sut/itr Dioxide Standard Cerlifical ion o(A deguacv 

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Map 21. 2015 

Table 1: 502 Ambient Concentrations (ppm): Annual Arithmetic Mean in Each Year, 2012 -2014 

Monitor Location 2012 2013 2014 

Concord* 0.001 0.001 0.001 

Londonderry 0.001 0.001 0.001 

Manchester** 0.002 -- --

Pembroke* 0.001 0.001 0.000 

Peterborough 0.001 0.001 0.001 

Portsmouth 0.001 0.001 0.001 

*Monitor is located within designated nonattainment area 

**Monitor was discontinued in Q2 of 2012 

Annual means from AQS AMP450 Quick Look Report 

Table 2 below provides the requested highest three (3)-hour S02 value and the number of 

times the 3-hour value equaled or exceeded 0.50 ppm in each year from 2012 through 2014. 

Based on the 3-hour values presented in Table 2 and those contained in the September 13, 2013 

submittal, at no time was the 0.50 ppm Priority II S02 threshold reached anywhere in the state. 

Table 2: 502 Ambient Concentrations (ppm): Highest 3-Hour Value and Number of Times 

the 3-Hour Value Equaled or Exceeded 0.50 ppm in Each Year, 2012 -2014 

Monitor Location 2012 2013 2014 

Concord* 0.017 (0) 0.011 (0) 0.01 {0) 

Londonderry 0.005 {0) 0.009 (0) 0.007 (0) 

Manchester** 0.014 (0) -- -

Pembroke* 0.042 (0) 0.024 (0) 0.021 (0) 

Peterborough 0.004 (0) 0.005 (0) 0.006 (0) 

Portsmouth 0.022(0) 0.019 (0) 0.027 (0) 

*Monitor is located within designated nonattainment area 

**Monitor was discontinued in Q2 of 2012 

Maximum 3-hour bulk averages AQS AMP440 Maximum Values Report 

Table 3 below provides the requested highest twenty four (24)-hour S02 value and the 

number oftimes the 24-hour value equaled or exceeded 0.10 ppm in each year from 2012 

through 2014. Based on the 24-hour values presented in Table 3 and those contained in the 

September 13, 2013 submittal, the Central New Hampshire Nonattainment Area (Pembroke 

monitor) is the only area ofNew Hampshire to have experienced ambient 24-hour S02 

concentrations in the Priority II range in years 2009, 2010 and 2011. The 24-hour S02 

concentrations in 2009, 2010 and 2011 rarely exceeded the 0.10 ppm level and in the most recent 

three year period the 24-hour S02 concentrations have not reached the 0.10 ppm level. In 

addition, installation of advanced so2 control technology further diminishes the probability of 

future excursions above this level. 
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Mav 2T, 2015 

Table 3: 502 Ambient Concentrations (ppm): Highest 24-Hour Value and Number of Times 

the 24-Hour Value Equaled or Exceeded 0.10 ppm in Each Year, 2012 -2014 

Monitor Location 2012 2013 2014 

Concord* 0.006 (O) 0.007 (O) 0.006 (O) 

Londonderry 0.004 (O) 0.004 (0) 0.004 (O) 

Manchester** 0.007 (0) - - Pembroke* 0.008 (O) 0.006 (O) 0.005 (0) 

Peterborough 0.003 (O) 0.004 (0) 0.004 (0) 

Portsmouth 0.006 (0) 0.009 (0) 0.008 (0) 

*Monitor is located within designated nonattainment area 

**Monitor was discontinued in Q2 of 2012 

Maximum 24-hour averages AQS AMP440 Maximum Values Report 

Based on this supplemental S02 monitoring data, New Hampshire qualifies as a Priority 

III region for so2 episode plans in accordance with 40 CFR 51 I 150(±) and hereby requests 

approval of this change. As a Priority III region for S02, New Hampshire is no longer required 

to develop episode plans in accordance with 40 CFR 51.1529(c). The requested supplemental 

S02 monitoring data and New Hampshire's request and approval to change to a Priority III 

region for S02 episode plans, satisfies the contingency plan requirements with respect to 

subparagraph 110(a)(2)(G) ofthe CAA. 

In addition, in the September 13, 2013 S02 submittal, DES had included several New 

Hampshire statutes for incorporation into the New Hampshire SIP. DES is now withdrawing the 

following statute from the submittal: NH RSA 125-C:15, Enforcement. 

If you have any.questions, please contact me at (603) 271-1088 or via email at 

Craig.Wright@des.nh.gov, or Michele Roberge of my staff at (603) 271-6793 or via email at 

Michele.Roberge@des.nh.gov. 

cc: Anne Arnold, EPA Region I 

Richard Burkhart, EPA Region I 

Sincerely, 

~ 0 ~-1!1 /.1--

Craig A. Wright 

Director 

Air Resources Division