### ATTACHMENT C Chemical Analyses

### Chemical Analyses

Photochemical assessment monitoring station (PAMS) sites monitor ozone, chemicals associated with ozone formation, and meteorological data. The data fromsites in Maine and Massachusetts have been analyzed by NHDES staff . Sites in these states were included because they are downwind and upwind ofNew Hampshire, respectively. The meteorological portionoftheanalysis is presented in Attachment D . Background Information The Clean Air Act Amendments of 1990 required EPA to promulgate regulations for the "enhanced" monitoring of ozone and its precursors for ozone nonattainment areas classified as serious, severe or extreme. Both Congress and EPA recognized the need for an improved understanding of the ozone problem, and better feedback mechanisms for evaluating the effectiveness of ozone control strategies. In 1993, EPA published the final rule detailing the minimumrequirements for PAMS, which includes measurements of nitrogen oxides (NOx), speciated volatile organic compounds (VOCs), and meteorological parameters. These monitoring regulations provide for the collection of an "enhanced" ambient air quality database which can be used to better characterize the nature and extent ofthe ozone problem, aid in tracking NOx and VOC emission inventory reductions, assess air quality trends, make attainment/nonattainment decisions, and evaluate photochemical grid-model performance. There are four different types of PAMS sites, each serving a specific monitoring purpose: a Type 1 is upwind ofthe urban area and represents background concentrations coming into the area; a Type 2 is on the downwind fringe ofthe urban area and represents maximumprecursor concentrations fromthe area; a Type 3 is located in an area with maximumozone concentrations; and a Type 4 is at extreme downwind location to represent long-range transport fromthe area. Therefore, PAMS sites required for an area will not necessarily all be located within the boundaries ofthe non-attainment area. New Hampshire currently operates two PAMS sites: Nashua (Type 1) and Peterborough (Type 3) . The Nashua site is located in a populated area near the southern border of the state, and is part of the Boston--Worcester--Lawrence Consolidated Metropolitan Statistical Area (CMSA) . The site in Peterborough is in Miller State Park on the summit of Pack Monadnock at an elevation of 2288 feet above sea level . Both sites are important for capturing the transport of ozone and its precursors into New Hampshire. 

### The distinguishing features that make PAMS sites truly "enhanced" ozone monitoring stations is that they collect meteorological, ozone and its precursors (oxides of nitrogen and VOCs) data simultaneously. Gaining a better understanding of how these variables interact with each other in realworld instances is necessary in order to effectively address ozone levels in New Hampshire and the rest ofthe nation. Description ofAnalyses Analysis of PAMS data focused on nitrogen oxides, PAMS target compounds (PAMHC), and total nonmethane organic carbons (TNMOC) in NewHampshire and the surrounding states of Maine and Massachusetts. Data were acquired through AQS for 1998 to 2010. Only hourly data were considered. In addition, some data were removed ifthey did not meet the following criteria: 

### " POC#was equal to 1 . 0 Data capture ofat least 60%(1757 hours) occurred during the period June-September .To provide a consistent base of comparison in the charts of PAMHC and TNMOC, data for these parameters froma given year were available for both parameters. NOx data were treated separately. 

### Due to a high number ofmonitoring sites in Massachusetts, afew with long-termdatasets were selected to illustrate NOx trends. After accounting for the above, data from the following sites were incorporated into thecharts shown below : New Hampshire

. Nashua, Gilson Road (33-011-1011)

. Peterborough, Pack Monadnock Summit in Miller State Park (33-011-5001)

. Portsmouth, Pierce Island (33-015-0014)

. Brentwood, South Road (33-015-0013) Maine



### . Cape Elizabeth, Two Lights State Park (33-005-2003)

. Portland, Marginal Way (23-005-0027) andStateStreet (23-005-0029)

. Kittery, Frisbee School (23-031-3002) -operated by NHDES

. Bar Harbor, Cadillac Mountain Summit, Acadia National Park (23-009-0102) 

### Massachusetts

. Boston, Kenmore Square (25-025-0002)

. Springfield, Liberty P-Lot (25-013-0016) 

### " Worcester, Central Street (25-027-0020) and Summer Street (25-027-0023) " Lynn, Parkland (25-009-2006) " Newbury, Sunset Blvd (25-009-4004)

. Milton, TopofBlue Hill (25-021-3003) " Chicopee, Anderson Rd (25-013-0008)

. Ware, Quabbin Summit (25-015-4002)

### New Hampshire Average NOx (June-September)
m a a c _o w c d c 0 U 10 8 6 4 2 0 1998 1999 20002001 20022003 20042005 2006 2007 2008 20092010 a Brentwood " Portsmouth c3Gilson [3 Mller



### Maine Average NOx (June-September) 35 30 a a 25 p 20 15 ~. c 10 c U 5 0 m Portland n Kittery pCadillac
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010



### MassachusettsAverage NOx (June-September) 

## m a c 0

, . c d v c 0 U 

## 70 60 50 40 30 20 10 0 " Boston m Springfield [3 Worcester ©Lynn m Newbury " Blue Hill 1998 199920002001 2002 20032004 2005 20062007 2008 2009 2010Average TNMOCand PAMHC(June-September) New Hampshire, Maine, Massachusetts

. . U m a o. v c 0 R c m c 0 U

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 TNMOCand PAMHCSeasonal Averages

Gilson Road, Nashua

2006 2007 2008 2009 2010
TNMOCand PAMHCSeasonal Averages Pack MonadnockSummit, Peterborough
v m a a c 0 c m c 0 U sTNMOC m PAMHC

m TNMOC a PAMHC "TNMOC

" PAMHC

2006 2007 2008 2009 2010