PAMS DATA VALIDATION FOR THE NORTHEAST STATES

Transcription

1 1360 Redwood Way, Suite C Petaluma, CA / FAX 707/ PAMS DATA VALIDATION FOR THE NORTHEAST STATES FINAL REPORT STI FR By: Steven G. Brown Hilary H. Main Sonoma Technology, Inc Redwood Way, Suite C Petaluma, CA Prepared for: Gary Kleiman Northeast States for Coordinated Air Use Management 101 Merrimac Street Boston, MA September 27, 2002

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3 ACKNOWLEDGMENTS The authors thank the NESCAUM states for continuing to support PAMS data collection, validation, and analysis efforts. We also thank the following individuals for their contributions: Gary Kleiman, NESCAUM, for overseeing the project. John Graham, NESCAUM, for thoughtful comments and discussion. Norm Beloin (EPA); Jeff Underhill and Jim Archer (New Hampshire); Andy Johnson, John Chandler, and Jeff Emery (Maine); Tom McGrath (Massachusetts); and Bob Henry, Garry Boynton, and Gopal Sistla (New York) for comments and discussion at the August 2002 meeting. Mary Mullen and Paul Nichols (Maine), Roy Heaton (Rhode Island), Tom McGrath (Massachusetts), Al Leston (Connecticut), and Garry Boynton (New York) for reinvestigating the data and providing us with their comments on the draft report. iii

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5 TABLE OF CONTENTS Section Page ACKNOWLEDGMENTS...iii LIST OF FIGURES...vii LIST OF TABLES...ix 1. INTRODUCTION Background Project Objectives And Scope PAMS Data Acquisition and Organization Validation Approach Guide to This Report GENERAL VALIDATION RESULTS Calibration Gas Carryover Peak Misidentification Samples with Possible Operating Problems Possible Column Contamination Butenes Summary RESULTS FOR INDIVIDUAL SITES Connecticut East Hartford Hamden Sherwood Island (Westport) Stafford Maine Acadia National Park Cape Elizabeth New Hampshire Brentwood Kittery New Jersey Rutgers/New Brunswick Camden Rider College New york Queens Bronx Rhode Island East Providence Greenwich v

6 TABLE OF CONTENTS (Concluded) Section Page 3.7 Massachusetts Agawam Borderland Chicopee Lynn Newbury Truro Ware SUMMARY REFERENCES APPENDIX A: TABLES OF SUSPECT AND INVALID SAMPLES FOR THE NORTHEAST REGION PAMS SITES A-1 APPENDIX B: SPECIES ABBREVIATIONS...B-1 vi

7 Figure LIST OF FIGURES Page 3-1. Example of consistently high t-2-butene baseline concentrations in 2000 at East Hartford Examples of possible calibration carryover of n-undecane at East Hartford in Time series of odd concentrations at East Hartford on August 22, 2001, at 0000 EST Fingerprint of odd concentrations of toluene, 2-methylhexane, 3-methylhexane, n-heptane, n-octane, and cyclohexane at East Hartford on August 22, 2001, at 0000 EST Example of possible calibration carryover of n-undecane at Sherwood Island on July 26, Example of a high baseline concentration of t-2-butene at Sherwood Island in Ethane concentrations at Acadia National Park in Example of possible column contamination of styrene at Acadia National Park in High baseline concentrations of 1,2,4-trimethylbenzene at Acadia National Park in High baseline concentrations of 1,2,4-trimethylbenzene at Acadia National Park in Example of possible column contamination of benzene at Acadia National Park in Example of possible column contamination of 2,4-dimethylpentane at Acadia National Park from June 20 to July 8, Examples of possible calibration carryover of n-undecane at Acadia National Park in Example of calibration carryover of n-undecane at Cape Elizabeth in Example of possible calibration carryover on June 18, 2001 at Rider College Suspect ethene concentrations on August 16-17, 2001, at Rider College Example of possible misidentification between 3-methylpentane and 2-methylpentane at Rider College on August 30, 2001, at 0500 EST vii

8 Figure LIST OF FIGURES (Concluded) Page Example of possible misidentification between benzene and cyclohexane on June 13, 2001, at 1000 EST, at Rider College Example of possible misidentification in several samples between toluene and 2,3,4-trimethylpentane at Rider College in Example of high baseline of several species at Rider College, on August 16-23, Example of an odd fingerprint at Queens on August 3, 2000, at 2200 EST Example of an odd fingerprint at Queens on August 28, 2001, at 0800 EST Example of an odd fingerprint at Queens on August 6, 2001, at Example of possible misidentification of cyclohexane and benzene at Bronx in Example of odd behavioral pattern switch of m-/p- and o-xylenes at E. Providence in Example of non-zero baseline concentrations of styrene at Chicopee in Example of a high baseline concentration of 2,2-dimethylbutane at Lynn from June 15 through July 12, Example of a high baseline concentration of 1,2,4-trimethylbenzene at Lynn in High baseline concentrations of n-decane and n-undecane at Lynn from June 15 through July 12, Example of non-zero styrene baseline concentrations at Newbury in Non-zero baseline concentrations of styrene at Truro in Non-zero baseline concentrations of styrene at Ware from July 13 through August 31, Consistently high concentrations of ethane at Ware in viii

9 LIST OF TABLES Table Page 1-1. Site locations, AIRS codes, site types, and sampling durations of NESCAUM sites validated for Approximate slope of the relationship between c-2-butene and t-2-butene by site Summary of available data in Connecticut Summary of available data in Maine Summary of available data in New Hampshire Summary of available data in New Jersey Summary of available data in New York Summary of available data in Rhode Island Summary of available data in Massachusetts Summary of percent available valid 2000 and 2001 data computed as [N available N entire samples flagged]/n expected * ix

10 1. INTRODUCTION 1.1 BACKGROUND Northeast States for Coordinated Air Use Management (NESCAUM) is an interstate association of the air quality control divisions of the eight northeast states: Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, and Vermont. An assessment of the data and operations of Photochemical Assessment Monitoring Stations (PAMS) currently operated by these states was conducted between September 2000 and June 2001 including validation and analysis of data from PAMS and PAMS-like sites in the NESCAUM and mid-atlantic region (Main and O Brien, 2001; Main and Roberts, 2001). Statistical summaries of these data were prepared and archived on the NESCAUM web site (Main and O Brien, 2001). 1 The project performed during 2000 and 2001 examined data from with a special emphasis on data collected in To continue the progress made with the validation, summary, and analysis of data, NESCAUM contracted with STI to expand the database through the validation and analysis of 2000 and 2001 PAMS data collected by Northeast states. Table 1-1 provides a list of sites for which validation was performed. Table 1-1. Site locations, AIRS codes, site types, and sampling durations of NESCAUM sites validated for Page 1 of 2 Site Location State AIRS Code Site Type a Duration Sample Cape Elizabeth ME hr Acadia Nat l Park ME hr East Hartford CT hr Hamden CT A 1 hr Sherwood Island CT /3 1 hr Stafford CT hr Borderland MA /3 3 hr Lynn MA hr Newbury MA hr Agawam MA hr Chicopee MA hr Ware MA hr Truro MA hr a PAMS Type 1 = upwind or background site; Type 2 = maximum ozone precursor emissions impact site; Type 2A = second Type 2 site required depending upon the size of the area; Type 3 = maximum ozone concentration site; Type 4 = extreme downwind monitoring site. Note that some sites can be both upwind and downwind of an area (e.g., Type 1/4). 1 See 1-1

11 Table 1-1. Site locations, AIRS codes, site types, and sampling durations of NESCAUM sites validated for Page 2 of 2 Site Location State AIRS Code Site Type a Duration Sample Brentwood NH hr Kittery NH hr Greenwich RI hr East Providence RI hr Bronx NY hr Queens NY A 1 hr Rutgers/New Brunswick NJ /4 1 hr Camden NJ A 1 hr Rider College NJ hr a PAMS Type 1 = upwind or background site; Type 2 = maximum ozone precursor emissions impact site; Type 2A = second Type 2 site required depending upon the size of the area; Type 3 = maximum ozone concentration site; Type 4 = extreme downwind monitoring site. Note that some sites can be both upwind and downwind of an area (e.g., Type 1/4). 1.2 PROJECT OBJECTIVES AND SCOPE The objectives of this project are to validate and analyze data from the existing PAMS network; summarize the data using median values and variances and prepare graphs of inter-annual and spatial trends; and use the data to deduce the effectiveness of selected emission control programs at reducing precursor concentrations to ozone in the Northeast states. The result of this project will be the development of basic statistical summaries and data products required for understanding the monitored data and its implications for current and future control programs. Such summaries may become the basis for future annual PAMS reports. This report summarizes the data validation portion of the project. 1.3 PAMS DATA ACQUISITION AND ORGANIZATION STI acquired and validated PAMS data from all NESCAUM states, including year-round, 24-hour data collected at PAMS Type II sites. Data were mostly acquired from AIRS with a few files in AIRS format supplied directly from Massachusetts. 2 Both Level 1 and Level 3 data validation were performed, as defined in the U.S. Environmental Protection Agency s (EPA ) 1996 PAMS Data Analysis Workshop (Main et al., 1996): Level 1 indicates observations have received quantitative and qualitative reviews for accuracy, completeness, and internal consistency. Level 3 is the continuing evaluation of the data as part of the data interpretation process. 1-2

12 For the final delivery of the data, we provided a data set of validated PAMS data from all sites in the NESCAUM region. The data set provides access to individual measurements (with quality control flags) and various aggregations and summary statistics. We will also provided documentation of the data files, including a description of all data sources and explanation of data formats (Main, 2002). 1.4 VALIDATION APPROACH VOCDat was used to perform the volatile organic compound (VOC) data validation. VOCDat allows the analyst to display the VOC data collected with automatic gas chromatographs (auto-gcs) and canister systems; to perform quality control (QC) tasks on the data; and to begin data analysis (Main and Prouty, 2000). VOCDat displays data using scatter, fingerprint, and time series plots. Scatter plots enable the investigation of the relationship among species at one site or at a number of sites. Fingerprint plots show the concentration of each species in a sample (in chromatographic order) and help identify unique characteristics of the samples. Time series plots show the concentrations of species in every sample over a specified time period and are useful in showing the diurnal behavior of a species. To validate a data set, we inspect a time series plot of every species, prepare numerous scatter plots, inspect the fingerprint plot of every sample, and compute and review summary statistics. Visual inspection is useful to identify diurnal patterns, concentration spikes, the periodicity of concentration increases or decreases, the relationship between various species, and sample-to-sample differences in the VOC composition (fingerprint). These investigations assist the analyst in establishing site-specific patterns in concentration, determining specific hours for which there are questions, singling out data collected during ozone episodes, and discovering problems in the data set that need correction. Specific investigations that we performed during data validation include the following: Checked the species list for missing abundant species. Sometimes a key hydrocarbon, such as toluene or o-xylene, does not get reported to AIRS. Samples with missing species were further inspected and flagged as possibly suspect. Ran custom screening checks that included checking each sample for the presence of abundant species, failure to meet typical relationships (e.g., benzene > toluene), and gross outliers. Samples that failed screening were reviewed in more detail. Prepared summary statistics including minimum, maximum, mean, and median values for each parameter. Inspected time series plots of every hydrocarbon (looking for diurnal variations, high and low values, relationships to other hydrocarbons). Prepared scatter plots of hydrocarbons that are likely to be emitted by the same source and that typically correlate well, including benzene and acetylene, propane and ethane, i-butane and n-butane, i-pentane and n-pentane, 2-methylpentane and 3-methylpentane, ethylbenzene and 1,2,4-trimethylbenzene, and the xylene isomers (o-xylene should be less than the sum of m-&p-xylenes); benzene and toluene (toluene concentrations typically exceed benzene and these species generally correlate well); toluene and 1-3

13 2-methylheptane (sometimes these species are misidentified); and every hydrocarbon and species group with total nonmethane organic compounds (TNMOC) (we looked for gross outliers). Inspected fingerprint plots of every sample with an emphasis on the flagged samples (based on the above investigations) and on the surrounding samples (looking for gaps in data, odd fingerprints, abrupt changes, and missing data). Identified samples or individual species that needed to be flagged. We also entered a comment about why a QC code was changed. VOCDat retains a list of these comments and the changes to the QC codes. Our strategy is to flag entire samples when we identify a problem with two or more of the most abundant species (e.g., toluene, i-pentane, i-butane, n-butane, benzene, acetylene, ethane, xylenes, ethane) or when a suspect hydrocarbon comprises 10% or more of the total. Individual species are flagged as suspect when there are problems noted and the concentration of the hydrocarbon is low compared to other species in the sample. Our approach is not to invalidate data, but to flag data as suspect that do not meet our conceptual model of hydrocarbon emissions, formation, and removal. The flags are placed on the data so that monitoring staff can check the data to rule out possible monitoring or analytical problems. After review of the data by the reporting agencies, some suspect data may be deemed invalid, some data may be reprocessed and re-reported by the agency, and other data may remain suspect (cause unknown). These latter samples remain flagged in the database for the attention of future data analysts. 1.5 GUIDE TO THIS REPORT Section 2 outlines general validation results in which general types of problems with the data are identified. Section 3 summarizes data validation results for individual sites. A summary of this report appears in Section 4 and references in Section 5. Appendix A lists all samples identified as suspect or invalid and reasons for QC code changes. Appendix B lists species abbreviations. 1-4

14 2. GENERAL VALIDATION RESULTS This validation effort builds on the review of the data (Main and O Brien, 2001). This section documents the general types of problems we identified in the data because many of the data problems could apply to nearly any site. 2.1 CALIBRATION GAS CARRYOVER Following a calibration gas sample on an auto-gc, some of the higher carbon number hydrocarbons can take several hours to clear the system (likely decay of the hydrocarbons from the cold trap). This problem typically affects n-decane, 1,2,3-trimethylbenzene, and n-undecane. The higher carbon number species are components of diesel exhaust; thus, having correct concentration data for these species is important in source apportionment. The pattern is easy to detect the hour preceding the high concentrations of undecane, for example, is blank, probably indicating a calibration run. The concentrations start high and tail off. We set the QC codes for the affected species as suspect. The concentrations involved are typically small (i.e., less than 2 ppbc); thus, TNMOC values are not significantly affected. For calibration carryover, the monitoring agency should invalidate the concentrations for decane and undecane for the affected samples, revise the sum of PAMS target species and the TNMOC, and re-report these data to AIRS. Most of the states have set up a procedure to address this, and few calibration carryover samples remain in the data sets. 2.2 PEAK MISIDENTIFICATION Misidentified species were rare in the 2000 and 2001 data, an improvement over previous years. The troublesome species in this data set were often the following: toluene, 2-methylheptane, and 2,3,4-trimethylpentane, benzene and cyclohexane; 2,3-dimethylbutane, 2-methylpentane, and 3-methylpentane; m-ethyltoluene, p-ethyltoluene, and sometimes 1,2,4-trimethylbenzene; and m-diethylbenzene and p-diethylbenzene Unless the species involved are not among the more abundant species or are present in very low concentrations, the samples reported with misidentification problems should not be used in most analyses because the TNMOC, sum of PAMS target species, and unidentified totals, as well as the misidentified species concentrations, may be in error. The misidentifications can be found using scatter, fingerprint, and time series plots. When misidentification problems occur, scatter plots show a scissors-like shape; typical relationships show either a strong correlation (i.e., the data lie along a line) or a cone of data. Chemists who have analyzed ambient air for hydrocarbons agree that there can be many interferences in the system that result in peak misidentification or peak misassignment. For 2-1

15 example, moisture in the sample, cold trap temperature fluctuation, column media decay, and temperature variation can contribute to problems in properly identifying a particular hydrocarbon. Oxygenated hydrocarbons are particularly troublesome as they can be present in large quantities and can coelute with many important PAMS target compounds. The use of a Nafion dryer can reduce, but not always eliminate, the oxygenate interference. Many of the problems we noted in our validation steps may stem from these types of analytical issues. These data need to be corrected by the reporting agencies before use in analyses. 2.3 SAMPLES WITH POSSIBLE OPERATING PROBLEMS Past experience has shown that cold trap temperature problems may be identified by low ethane, compared to benzene, concentrations. We flagged samples with missing or zero ethane as suspect. We often found that, if ethane was missing or zero, the sample exhibited other problems. These samples should be reviewed by the reporting agencies to assess whether the data are valid. 2.4 POSSIBLE COLUMN CONTAMINATION Samples with potential contamination problems were flagged as suspect. Some data exhibited high concentrations of one or more species with concentrations tailing off over hours, days, or weeks. These incidences could be caused by problems with the operating or analytical systems, off-gassing of new shelter materials, or other unknown problems. Typically, we flagged just the species that were affected unless the concentrations were very high. The TNMOC, sum of PAMS target species, and species group totals are affected as well. Species that exhibited this problem most frequently included ethane, ethene, benzene, 1,2,4-trimethylbenzene, and styrene. Apparent contamination occurred less commonly with 2,4-dimethylpentane. A related, but cause unknown, pattern noted in the data was apparent high baseline concentrations of several species including t-2-butene, 1,2,4-trimethylbenzene, 1-butene, 2,2-dimethylbutane, and styrene. The monitoring agencies should inspect and possibly correct or invalidate these data. 2.5 BUTENES Several sites had elevated levels of t-2-butene (and sometimes c-2-butene), particularly in 2000 and Discussions with state staff and additional investigation raised more questions than provided answers. Table 2-1 provides approximate slopes of the relationships between c-2-butene and t-2-butene by site. This table is provided as food for thought for future discussions. 2-2

16 Table 2-1. Approximate slopes of the relationship between c-2-butene and t-2-butene by site. Site c-2-butene: Comments t-2-butene Acadia, ME 1:3 Poor correlation between the species; consistent with far downwind site Cape Elizabeth, ME 1:1 prior to : and 2001 Kittery, ME 1:1 Agawam, MA 1:1 Borderland, MA 1:1 Chicopee, MA 5:1 in :1 other years Lynn, MA 1:1 Newbury, MA 1:2 in :1 in 2001 Ware, MA Low concentrations Brentwood, NH 1:1 Poor correlation Bronx, NY 1:1 Queens, NY 1:1 Camden, NJ 1:1 Poor correlation in 1997 New Brunswick, NJ 1:1 Many outliers in 1997 Rider College, NJ 1:1 E. Hartford, CT 1:4 in :1 other years Hamden, CT 1:4 in 1999 and :1 in 2000 Sherwood Island, CT 1:4 in :1 other years Stafford, CT 1:1 and 1:3 Combination of results among all years E. Providence, RI 1:1 W. Greenwich, RI Concentrations mostly below detection 2.6 SUMMARY Appendix A of this report contains a list of all suspect and invalid samples in the data from each site. The flags are placed on the data so that reporting agencies can check the data to rule out possible monitoring or analytical problems. After review of the data by the reporting agencies, some suspect data may be deemed invalid, some data may be reprocessed and rereported by the agency, and other data may remain suspect (cause unknown). These latter samples remain flagged in the database for the attention of future data analysts. Thus, the tables provide information to the data analyst regarding species and samples of concern. 2-3

17 3. RESULTS FOR INDIVIDUAL SITES The tables in Appendix A list all samples we identified as suspect or invalid and provide reasons for QC code changes. In many cases it is difficult to understand what the problem is or how to identify the problem with only the comments we provide. This section summarizes findings for the various sites, including additional narrative about the problems and example screen shots from VOCDat to illustrate how we observed the problems. This section should be useful to monitoring personnel for analytical issues and to data analysts for observations of unusual features in the data. We recognize the hard work it requires to collect, analyze, quality assure, and report PAMS data. Our comments and observations are intended to encourage the learning process for both analysts and monitoring staff. The data quality has improved over the years as everyone has gained experience. 3.1 CONNECTICUT Overall, data quality from the Connecticut sites is very good. Data validation details for each site are provided in following subsections and in Appendix A; data availability is summarized in Table 3-1. Table 3-1. Summary of available data in Connecticut. AIRS Site Code East Hartford Hamden Sherwood Island Stafford Year Sampling Period Number of expected samples Number of available samples Number of samples with individual species flagged Number of entire samples flagged % of valid and available data a /1-8/ /1-9/ /31-9/ /5-9/ /31-9/ /31-9/ /30-9/ /20-8/ a Computed as [N available N entire samples flagged]/n expected* East Hartford The overall data quality at East Hartford was very good. Data were available for the entire summer (June-August) for both 2000 and 2001 (see Table 1-1). It is noted that t-2-butene (t2bte) appears to have a high baseline (or minimum value) in 2000, as shown in Figure 3-1. This compound was not flagged, however, as Connecticut personnel believe these concentrations were real and not due to a system contaminant. Two observations are worth noting: (1) the t-2-butene concentrations were higher in 2000 and 2001 than in 1999 and 3-1

18 previous years and (2) there was very little diurnal pattern in the East Hartford t-2-butene data (a relatively constant concentration of ppbc when other species were near zero). Additional analysis should be performed to understand these observations. Figure 3-1. Example of consistently high t-2-butene (t2bte) baseline concentrations in 2000 at East Hartford. For contrast, 1-butene (1bute) and c-2-butene (c2bte) are also shown. Benzene concentrations were also noticeably higher in 2000 compared to other years although the pattern appears to be real; the data were not flagged. Year 2000 undecane data were flagged a few times due to possible calibration carryover, an example of which is shown in Figure 3-2. In 2001, one toluene data point (June 19, 2001, at 1300 EST, 491 ppbc) and the entire sample collected on August 22, 2001, at 0000 EST (see Figures 3-3 and 3-4) were flagged as suspect because of odd, extremely high concentrations that were not consistent with other data Hamden Data at Hamden were available for the entire summers of 2000 and 2001; no samples or species were flagged. The t-2-butene did not have a high baseline concentration as found at other locations. 3-2

19 Figure 3-2. Examples of possible calibration carryover of n-undecane (nundc) at East Hartford in ,2,3-trimethylbenzene (123tmb) and n-decane (ndec) also appear to be affected. Figure 3-3. Time series of odd concentrations at East Hartford on August 22, 2001, at 0000 EST. Species abbreviations are provided in Appendix B. 3-3

20 Figure 3-4. Fingerprint of odd concentrations of toluene, 2-methylhexane, 3-methylhexane, n-heptane, n-octane, and cyclohexane at East Hartford on August 22, 2001, at 0000 EST Sherwood Island (Westport) Sherwood Island had complete data for the summers of 2000 and In 2000 one instance occurred of apparent calibration carryover of undecane, and this species was flagged (see Figure 3-5). The t-2-butene data exhibited high baseline concentrations for both years (see an example for 2000 in Figure 3-6). The hydrocarbon s minimum concentration was often about 5 ppbc even when the concentrations of other more abundant compounds such as ethane and propane were less than 2 ppbc. Other observations of the t-2-butene data include the following: The higher concentrations appear to have occurred when winds were from the south or southwest. The diurnal pattern was very smooth; concentrations were higher in the midday or afternoon and lower during the night. Higher concentrations were found when temperatures were higher. All these observations are consistent with the possible photochemical production of t-2-butene. We are troubled by the apparent gradual increase in the baseline concentration as the PAMS season progressed, but this pattern may be a function of solar radiation and temperature. The t-2-butene data were not flagged although the cause of elevated concentrations is unknown. 3-4

21 Figure 3-5. Example of possible calibration carryover of n-undecane (nundc) at Sherwood Island on July 26, 2000 (note the exponential decay of the undecane concentration over several hours). Species abbreviations are provided in Appendix B. Figure 3-6. Example of a high baseline concentration of t-2-butene (t2bte) at Sherwood Island in Stafford Data were available at Stafford for all of June-August 2000 but were only available from June 21 through August 3, A large number of samples in both years reported propene and xylene (m-/p- and o-) concentrations below the detection limit. However, low concentrations of 3-5

22 propene and xylenes are expected at this site because it is far downwind from sources. Some undecane data were flagged in 2000 due to suspected calibration carryover. 3.2 MAINE The overall data quality at Cape Elizabeth was very good. The Acadia data, however, contained a number of anomalies that should be investigated further. Data availability is summarized in Table 3-2. Table 3-2. Summary of available data in Maine. Site AIRS Code Year Sampling Period Number of expected samples Number of available samples Number of samples with individual species flagged Number of entire samples flagged % of valid and available data a Acadia Nat l /1-9/ Park /3-9/ Cape /1-9/ Elizabeth /1-9/ a Computed as [N available N entire samples flagged]/n expected* Acadia National Park Data were available at Acadia National Park from May through September for both 2000 and The data provide the following observations: Ethane concentrations showed an odd downward trend through the first month of sampling in both years. An example of this is shown in Figure 3-7. This pattern is usually indicative of contamination slowly being removed from the system. This species was flagged for further review from May 1 to July 3, 2000 (where it appears to flatten out to a consistent baseline ) and from May 1 to July 9, Subsequent review indicates this may be a seasonal effect and the data are valid. In 2000, styrene concentrations were high until June 22 (see Figure 3-8). Note, however, that these values are near the detection limit and therefore have little effect on the sample concentrations. 1,2,4-trimethylbenzene had a consistently high baseline concentration of around 0.9 ppbc in 2000 (see Figure 3-9) and showed possible column contamination through mid-july 2001 before settling at a lower baseline of 0.4 ppbc (see Figure 3-10); this species was flagged as suspect for both years 3. In both years, t-2-butene had a high baseline concentration of about 0.35 ppbc. This is similar to the pattern observed in t-2-butene concentrations in Connecticut and may be indicative of a regional background concentration. 3 Maine staff note that blanks for 1,2,4-trimethylbenzene are consistently high and therefore a problem. However, staff note that column contamination is unlikely; rather, these data indicate a problem with contamination prior to the GC. 3-6

23 Figure 3-7. Ethane (ethan) concentrations at Acadia National Park in This is likely a seasonal effect (and therefore, valid data). Figure 3-8. Example of possible column contamination of styrene (styr) at Acadia National Park in Concentrations are quite low. 3-7

24 Figure 3-9. High baseline concentrations of 1,2,4-trimethylbenzene (124tmb) at Acadia National Park in Figure High baseline concentrations of 1,2,4-trimethylbenzene (124tmb) at Acadia National Park in

25 Benzene exhibited higher concentrations from May 1 to July 26, 2001; because this coincides with the steady decrease of ethane, samples were flagged as suspect for further review. During this period, benzene concentrations stayed consistently high ( high is used in a relative sense) when other species were not (shown in Figure 3-11). These data are likely valid. Additionally in 2001, 2,4-dimethylpentane concentrations showed evidence of column contamination from June 20 through July 8 (see Figure 3-12); this hydrocarbon was flagged as suspect. We cannot explain these data after further review, but contamination was indicated as unlikely by the Maine staff. There were a number of instances in both years in which 1,2,3-trimethylbenzene, decane, and undecane were flagged because of suspected calibration carryover (shown in Figure 3-13) Cape Elizabeth Data were available for May through September 2000 and There were a number of instances in both years in which 1,2,3-trimethylbenzene, decane, and undecane were flagged because of suspected calibration carryover. These have now been corrected by Maine staff. Examples are shown in Figure Figure Example of possible column contamination of benzene (benz) at Acadia National Park in

26 Figure Example of possible column contamination of 2,4-dimethylpentane (24dmp) at Acadia National Park from June 20 to July 8, Figure Examples of possible calibration carryover of n-undecane (nundc) at Acadia National Park in Species abbreviations are provided in Appendix B. 3-10

27 Figure Example of calibration carryover of n-undecane (nundc) at Cape Elizabeth in Species abbreviations are provided in Appendix B. 3.3 NEW HAMPSHIRE Data at the New Hampshire PAMS sites were of good quality; overall availability is summarized in Table 3-3. Table 3-3. Summary of available data in New Hampshire. Site AIRS Code Year Sampling Period Number of expected samples Number of available samples Number of samples with individual species flagged Number of entire samples flagged % of valid and available data a Brentwood /29-9/ /2-9/ Kittery /29-9/ /1-8/ a Computed as [N available N entire samples flagged]/n expected* Brentwood In 2000, two samples reported TNMOC as less than the sum of target species; the TNMOC values were flagged in both cases. In 2001, the entire sample from August 24, at 1600 EST, was flagged because the unidentified fraction was more than 80% of the TNMOC. In both 2000 and 2001, m- and p-ethyltoluene almost always appear to either coelute or be 3-11

28 misidentified because only one species is reported and the other is zero; these species were flagged as suspect when this occurred Kittery In 2000, two samples reported TNMOC as less than the sum of target species; the TNMOC values were flagged in both cases. On May 29, 2000, at 0100 EST, 2-methylheptane appears to be misidentified with toluene; this sample was flagged. There were four samples in 2001 in which n-decane was flagged due to suspected calibration carryover. On July 26, 2001, at 1200 EST, all hydrocarbons were reported as 9978 the AIRS null code for voided by operator ; this sample was also invalidated in VOCDat. There were many samples in which species such as ethene and propene were below the detection limit although this is consistent with aged air occasionally impacting the site. Twenty-four-hour carbonyl compound data were available every sixth day from June 11 to August 28, No species or samples were flagged. Three-hour carbonyl data were available every third day from June 2 to August 31, 2000; no data were flagged. 3.4 NEW JERSEY The data were generally of good quality for most of the New Jersey sites. Data at Rider College was flagged for a period of about a week due to high baseline concentrations of all species. Data availability is summarized in Table 3-4. Table 3-4. Summary of available data in New Jersey. Site AIRS Code Year Sampling Period Number of expected samples Number of available samples Number of samples with individual species flagged Number of entire samples flagged % of valid and available data a Rutgers/ /31-8/ New /1-8/ Brunswick Camden /1-8/ /1-8/ Rider /31-8/ College /1-8/ a Computed as [N available N entire samples flagged]/n expected* Rutgers/New Brunswick In 2000, the only flagged data were from odd high concentrations of 2,3-dimethylpentane (June 30 at 1400 EST) and 2,2,4-trimethylpentane (August 17 at 0100 EST) that occurred when 3-12

29 other species concentrations were low. In 2001, n-nonane and n-decane concentrations were unusually high on August 27 at 1300 EST and were both flagged. The C9-C12 alkane concentrations were all unusually high on August 22 at 1000 EST, and the entire sample was flagged. The entire sample was also flagged on June 4, 2001 at 1900 EST due to extremely high unidentified mass concentrations Camden There were two instances in 2000, identified by scatter plot analysis, in which 3-methylpentane appears to be reported with 2,3-dimethylbutane; both of these species were flagged. In 2000 and 2001, n-decane, n-undecane, and 1,2,3-trimethylbenzene were flagged a few times because of suspected calibration carryover. A possible cold trap problem occurred on August 10, 2000 at 2300 EST, in which ethane was reported below detection limit and benzene was more than 5 ppbc; this sample was flagged. Three-hour carbonyl data were availably every third day from 6/17-9/9 in 2000; no data were flagged Rider College The 2000 and 2001 n-decane, n-undecane, and 1,2,3-trimethylbenzene data were flagged a few times due to suspected calibration carryover (e.g., Figure 3-15). In 2001, the period from August 16, at 1100 EST, to August 17, at 1000 EST, exhibited a huge spike in ethene (252 ppbc) and a long gradual decrease over 24 hours; a column contamination appears to have occurred (see Figure 3-16). Because the ethene concentrations were so high, we flagged the samples as suspect during this period. Scatter plot analysis showed evidence, in 2001, of misidentification between 2-methylpentane and 3-methylpentane (see Figure 3-17), benzene and cyclohexane (see Figure 3-18); and toluene and 2,3,4-trimethylpentane (see Figure 3-19); these species were flagged. Samples from the entire period between August 16, 1000 EST, and August 23, 2001, 0800 EST, appear to have a raised baseline concentration, or contamination problem, for all species (Figure 3-20); samples from this period were flagged as suspect. On August 30, 2001, from 0000 to 0700 EST, the calculation of total PAMS species is greater than TNMOC; the sum of PAM species and TNMOC values were flagged during this period. 3-13

30 Figure Example of possible calibration carryover on June 18, 2001 at Rider College. Species abbreviations are provided in Appendix B. Figure Suspect ethene (ethyl) concentrations on August 16-17, 2001, at Rider College. Species abbreviations are provided in Appendix B. 3-14

31 Figure Example of possible misidentification between 3-methylpentane (3mpna) and 2-methylpentane (2mpna) at Rider College on August 30, 2001, at 0500 EST. Figure Example of possible misidentification between benzene (benz) and cyclohexane (cyhxa) on June 13, 2001, at 1000 EST, at Rider College. 3-15

32 Possible misidentified samples Figure Example of possible misidentification in several samples between toluene (tolu) and 2,3,4-trimethylpentane (234tmp) at Rider College in Figure Example of high baseline of several species at Rider College, on August 16-23, Species abbreviations are provided in Appendix B. 3-16

33 3.5 NEW YORK At both sites and in both years, propene was invalidated by NY staff in the entire data set due to coelution with a contaminant. This will affect the calculation of TNMOC, total olefins, weight percent, and reactivity weight percent, and should be kept in mind when comparing to other sites. A summary of data availability is provided in Table 3-5. Table 3-5. Summary of available data in New York. Site AIRS Code Year Sampling Period Number of expected samples Number of available samples Number of samples with individual species flagged Number of entire samples flagged Queens /16-9/ Bronx a % of valid and available data a /21-9/ /16-9/ /5-9/ Computed as [N available N entire samples flagged]/n expected* Queens In 2000, a number of samples with odd fingerprints showed unusually high n-nonane, p-ethyltoluene, 1,3,5-trimethylbenzene, o-ethyltoluene, n-decane, 1,2,3-trimethylbenzene, m-diethylbenzene, p-diethylbenzene, and n-undecane concentrations; these species were flagged for the periods, August 3 at 1600 EST to August 4 at 0200 EST and August 4 from 1700 to 2100 EST. A likely source of these hydrocarbons is a solvent. An example is shown in Figure Due to suspected calibration carryover in 2000, 1,2,3-trimethylpentane, n-decane, and n-undecane were flagged a number of times. Two samples were flagged because TNMOC was reported equal to zero (July 21, 2000, at 0900 EST and September 26, 2000, at 0800 EST). In 2001, a few samples with odd fingerprints were flagged (unusually high ethylbenzene, m-,p- and o-xylenes, C9-11 alkanes, p- and o-ethyltoluene, 1,2,3-trimethylbenzene, m- and p-diethylbenzene); these samples are shown in Figures 3-22 and Three samples showed high m-ethylbenzene (>100 ppbc) and other species with low concentrations; this hydrocarbon was flagged 5. Three-hour carbonyl data were available every third day from May 24 through September 6, 2000; no data were flagged. 4 These are real, valid data; the suspect flag is a warning to analysts. 5 These are real, valid data; the suspect flag is a warning to analysts. 3-17

34 Figure Example of an odd fingerprint at Queens on August 3, 2000, at 2200 EST. N-decane is the highest peak at 232 ppbc, C9 and C11 aromatic hydrocarbons are next at 70 ppbc, and 1,2,4-trimethylbenzene at 55 ppbc. Figure Example of an odd fingerprint at Queens on August 28, 2001, at 0800 EST. The two highest peaks are m-diethylbenzene (198 ppbc) and m-/p-xylenes (184 ppbc), followed by n-undecane (139 ppbc), n-decane (78 ppbc), o-xylene (58 ppbc), ethylbenzene (49 ppbc) and p-ethyltoluene (43 ppbc). 3-18

35 Figure Example of an odd fingerprint at Queens on August 6, 2001, at The highest peaks are n-undecane (136 ppbc), n-decane (71 ppbc), m-diethylbenzene (40 ppbc), and n-nonane (25 ppbc) Bronx 1,2,3-trimethylpentane, n-decane and n-undecane were flagged a number of times due to suspected calibration carryover in Several samples also had unidentified concentrations of more than 90% of the TNMOC in 2000; these samples were flagged as suspect 6. In 2001, there was an apparent misidentification between benzene and cyclohexane, as shown in Figure 3-24; these species were flagged. Twenty-four-hour carbonyl compound data were available every third day (January 1-December 31, 2000). No data were flagged as suspect. Three-hour carbonyl data were available every third day from May 24 through September 6, 2000; no data were flagged. 6 These are real, valid data; the suspect flag is a warning to analysts. 3-19

36 Misidentified samples Figure Example of possible misidentification of cyclohexane (cyhxa) and benzene (benz) at Bronx in RHODE ISLAND The quality of the data from Rhode Island was good; all flagged samples are detailed in Appendix A. Overall availability is found in Table 3-6. Table 3-6. Summary of available data in Rhode Island. Number of expected Number of available Number of samples with individual species Number of entire samples % of valid and available data a Site AIRS Code Year Sampling Period Sampling Frequency samples samples flagged flagged East /1-8/31 3 hr Providence /1-8/31 3 hr Greenwich /1-8/31 3 hr, third day a /2-8/29 3 hr, third day Computed as [N available N entire samples flagged]/n expected*

37 3.6.1 East Providence In 2000, one sample (July 19 at 2300 EST) was flagged because concentrations of C2-C5 hydrocarbons were reported below the detection limit 7. A number of samples showed a high unidentified fraction (>50%) in both years although these were not flagged. From June 1 to July 30, 2001, o-xylene was consistently higher than m-/p-xylenes (see Figure 3-25). Further investigation suggests that the decimal point indicator in the AIRS file may be wrong; if the m- &p-xylenes data are multiplied by a factor of 10, the values appear to be correct. Twenty-four-hour hydrocarbon, chlorinated, and brominated species data were available every sixth day in These data were also available every sixth day in 2001from January 1 to September 28. Twenty-four-hour carbonyl compound data were available every third day in 2000 and No data were flagged Greenwich As seen in other samples, in 2000, 1-butene concentrations appeared to have a baseline throughout the year at about ppbc. This species was not flagged, however, pending review by Rhode Island staff. Several samples had a high unidentified mass fraction (>50%) in both years although they were not flagged. High unidentified mass is not unusual at a rural site because of the presence of photochemical products in the aged air mass. Figure Example of odd behavioral pattern switch of m-/p- and o-xylenes at E. Providence in This was verified in the AIRS files; the AIRS file is in error according to Rhode Island staff. We are uncertain why this is the case. 3-21

38 3.7 MASSACHUSETTS Only 2000 data were available at the time of this analysis; they are summarized in Table 3-7. Other than a number of instances of evident high baseline concentrations, the data quality was good. a AIRS Site Code Agawam Borderland Chicopee Lynn Newbury Truro Ware Table 3-7. Summary of available data in Massachusetts. Year Sampling Period Number of expected samples Number of available samples Number of samples with individual species flagged Number of entire samples flagged % of valid and available data a /1-8/ /1-8/ /1-8/ /1-8/ /1-8/ /2-8/ /1-8/ Computed as [N available N entire samples flagged]/n expected* Agawam The TNMOC concentration was reported as zero on July 19, 2000, at 2300 EST, even though individual species concentrations were available; the sample was flagged as suspect Borderland There was an odd, high concentration of 1,2,4-trimethylbenzene when other species were at low concentrations on July 13, 2000, at 2300 EST; this compound was flagged as suspect Chicopee Styrene had a high baseline concentration with a steady decline over a number of days from June 28 through July 6, 2000, and from August 1 through 31, 2000 (see Figure 3-26). Styrene was flagged as suspect during these periods. There appears to be some misidentification between cyclohexane and benzene based on scatter plot analysis; the two species were flagged for each of the four samples. 3-22

39 Twenty-four-hour hydrocarbon data were available every sixth day for the entire year 2000, and carbonyl compound data were available from January 1 through September 21, In 2001, carbonyl compound data were available every sixth day from January 25 through February 12 and from September 28 through October 28. No data were flagged as suspect. Three-hour carbonyl data were available every third day from August 25 through 31, No data were flagged as suspect. Figure Example of non-zero baseline concentrations of styrene (styr) at Chicopee in Lynn A number of species exhibited high baseline concentrations. 2,2-dimethylbutane concentrations were consistently high from June 15 through July 12, 2000, and were flagged as suspect during this period (see Figure 3-27). 1,2,4-trimethylbenzene had a baseline concentration of about 1.9 ppbc during the entire summer 2000 (see Figure 3-28) and was flagged as suspect 8. Both n-decane and n-undecane exhibited high baseline concentrations from June 15 through July 12, 2000 (see Figure 3-29) and were flagged as suspect. A few samples had high cyclohexane (> 10 ppbc) with benzene less than 3 ppbc and were flagged due to possible misidentification. 8 Massachusetts staff note this has been a universal outlier throughout PAMS years; it is likely that the elevated concentrations constitute a system contaminant. Some samples with odd high baselines were reported during periods in which the auto-gc was exhibiting marginally acceptable baselines. 3-23

40 Twenty-four-hour data were available every sixth day in 2000; hydrocarbons were available from January 1 through August 31 while carbonyl compound data were available from January 1 through November 15. In 2001, carbonyl compounds were sampled from January 1 through May 1 and September 10 through October 28. No data were flagged as suspect. Three-hour carbonyl data were available every third day in 2000 from June 2 through August 31. No data were flagged as suspect. Figure Example of a high baseline concentration of 2,2-dimethylbutane (22dmb) at Lynn from June 15 through July 12, The 2,3-dimethylbutane (23dmb) concentrations are shown for contrast. 3-24

41 Figure Example of a high baseline concentration of 1,2,4-trimethylbenzene (124tmb) at Lynn in Figure High baseline concentrations of n-decane (ndec) and n-undecane (nundc) at Lynn from June 15 through July 12,

42 3.7.5 Newbury There was a high baseline concentration of styrene from June 29 through August 31, 2000 (see Figure 3-30); this hydrocarbon was flagged as suspect for the entire period Truro Styrene exhibited a baseline concentration of about 0.4 ppbc during the entire summer and was flagged (see Figure 3-31) Ware Styrene had a high baseline concentration from July 13 to August 31, 2000 (see Figure 3-32) and was flagged as suspect. The t-2-butene also exhibited a high baseline concentration of about 0.3 ppbc but was not flagged pending review by Massachusetts staff. These concentrations may be consistent with the t-2-butene concentrations observed at East Hartford, Connecticut. Ethane was consistently above 1.4 ppbc during the entire summer (see Figure 3-33) typical for the Northeast PAMS data. There was one sample in which 2-methylpentane and 3-methylpentane appear to be misidentified (high concentration of one and zero of the other); these species were flagged (June 27, 2000 at 1600 EST) 9. Figure Example of non-zero styrene (styr) baseline concentrations at Newbury in Misidentification was likely due to high concentrations of biogenics which coelute with the lower concentrations of the target species. 3-26

43 Figure Non-zero baseline concentrations of styrene (styr) at Truro in Figure Non-zero baseline concentrations of styrene (styr) at Ware from July 13 through August 31,

44 Figure Consistently high concentrations of ethane (ethan) at Ware in Propane (propa) concentrations are shown for contrast. 3-28

45 4. SUMMARY The objective of this task was to perform Level 1/3 data validation on the PAMS data collected in the Northeast states. This report documents the data quality, summarizes the problems that were observed in the data, and lists the samples that were flagged as suspect and invalid. Section 3 summarized individual samples and species. These samples were reviewed by the monitoring staff. Some data were revised as noted. Other samples were verified as valid, but odd. These samples remain flagged as a caution to data analysts. The data quality and availability is excellent at most sites (Table 4-1); thus, data analyses will not be affected in most cases. Note that in our summary, we base the computation of expected samples on the dates of collection and total possible number of samples per day. This computation does not take into account the hours which were dedicated to calibrations because the frequency and number of hours involved varied from site to site. Thus, we included a field to comment on the number of entire samples flagged. Table 4-1. Summary of percent available valid 2000 and 2001 data computed as [N available N entire samples flagged]/n expected * 100. Site Location State Year 2000 Year 2001 Comment Cape Elizabeth ME No samples flagged Acadia Nat l Park ME /3 to ½ of the samples were flagged, however, subsequent analyses indicate the ethane and benzene data are valid. East Hartford CT Only two entire samples flagged (2001) Hamden CT No samples flagged Sherwood Island CT No samples flagged Stafford CT No samples flagged Borderland MA 97 No samples flagged Lynn MA 88 No samples flagged Newbury MA 88 No samples flagged Agawam MA 99 No samples flagged Chicopee MA 89 No samples flagged Ware MA 83 No samples flagged Truro MA 98 No samples flagged Brentwood NH One entire sample was flagged (2000) Kittery NH No samples flagged Greenwich RI No samples flagged East Providence RI Three and one entire samples flagged (2000 and 2001, respectively) Bronx NY Fifty-five entire samples were flagged (2000) Queens NY Two and six entire samples flagged (2000 and 2001, respectively) Rutgers/New Brunswick NJ Two entire samples flagged (2001) Camden NJ No samples flagged Rider College NJ One entire sample was flagged (2000) 4-1

46 5. REFERENCES Main H.H. and O'Brien T. (2001b) Statistical summary of PAMS data collected in the Northeast and Mid-Atlantic states. Report prepared for NESCAUM,Boston, MA by Sonoma Technology, Inc., Petaluma, CA, STI FR2, June. Main H.H. and Prouty J.D. (2000) VOCDat user's guide. Prepared for U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Research Triangle Park, NC by Sonoma Technology, Inc., Petaluma, CA, STI UG, October. Main H.H. and Roberts P.T. (2001) Recommendations for the PAMS network in the Northeast and Mid-Atlantic States. Report prepared for NESCAUM, Boston, MA by Sonoma Technology, Inc., Petaluma, CA, STI FR, June. Main H.H., Roberts P.T., and Korc M.E. (1996) PAMS data analysis workshop: illustrating the use of PAMS data to support ozone control programs. Prepared for U.S. Environmental Protection Agency, Research Triangle Park, NC, presented at EPA Region I Headquarters, Boston, MA by Sonoma Technology, Inc., Santa Rosa, CA, STI WD3, October. 5-1

47 APPENDIX A TABLES OF SUSPECT AND INVALID SAMPLES FOR THE NORTHEAST REGION PAMS SITES This appendix contains tables that list the samples and individual hydrocarbons that were flagged as suspect (QC code = 7) or invalid (QC code = 8). Our strategy is to flag entire samples when we identify a problem with two or more of the most abundant species (e.g., toluene, i-pentane, n-pentane, i-butane, n-butane, benzene, acetylene, ethane, xylenes, ethene). We also flag samples when only one hydrocarbon has been identified as problematic if that hydrocarbon represents a significant portion of the TNMOC (e.g., more than 20%). Individual species are flagged as suspect when there are problems noted, but the concentration of the hydrocarbon is low compared to other species in the sample. Data are flagged that do not fit our conceptual model of ambient VOC concentrations and relationships. In some cases, the samples may have an analytical error that needs to be corrected or a sampling problem that was inadvertently missed or may just appear odd. After review of the data by the reporting agencies, some suspect data may be deemed invalid, some data may be reprocessed and re-reported by the agency, and other data may remain suspect (cause unknown). These latter samples remain flagged in our working database and require the attention of data analysts. The tables in Appendix A are configured as follows: Date = date of sample flagged (all hours are EST) Action = Change in the QC code (typically to 7 suspect, to 8 invalid, or to 1 - calibration). Actions are taken on individual species and on entire samples (Record). Validation notes = comments regarding why samples were flagged. Species abbreviations are provided in Appendix B. Where a series of samples were flagged (e.g., several days in a row), we consolidated the entries into one line of the table and summarized the number of samples flagged in the entire year. Tables A-1 through A-32 are organized by state, site, and year: A-1

48 East Hartford, Stafford, Hamden, and Sherwood Island, Connecticut (Tables A-1 through A-4) Acadia, Cape Elizabeth, and Kittery Maine (Tables A-5 through A-10) Agawam, Borderland, Chicopee, Lynn, Newbury, Truro, and Ware, Massachusetts (Tables A-11 through A-17) Brentwood, New Hampshire (Tables A-18 and A-19) Camden, Rider College, and New Brunswick, New Jersey (Tables A-20 through A-25) Bronx and Queens New York (Tables A-26 through A-29) Providence and West Greenwich, Rhode Island (tables A-30 through A-32) A-2

49 Table A-1. Samples flagged by STI at the East Hartford, CT PAMS site in 2000 (total = 18 samples). 6/7/ :00 PM through 6/7/2000 3:00 PM nundc QC code set to 7 calibration carryover 6/15/ :00 through 6/15/2000 2:00 PM nundc QC code set to 7 calibration carryover 6/16/ :00 through 6/16/2000 3:00 PM nundc QC code set to 7 calibration carryover 7/20/2000 2:00 PM through 7/20/2000 5:00 PM nundc QC code set to 7 calibration carryover Table A-2. Samples flagged by STI at the East Hartford, CT PAMS site in 2001 (total=2 samples). 8/22/2001 0:00 Record QC code set to 7 unusually high conc of tolu, 2mhexa, 3mhexa, nhept, noct, cyhex 6/19/ :00 Record QC code set to 7 unusually high conc of tolu Table A-3. Samples flagged by STI at the Stafford, CT PAMS site in 2000 (total = 9 samples). 6/26/2000 1:00 PM through 6/26/2000 3:00 PM nundc QC code set to 7 calibration carryover? 7/26/2000 1:00 PM through 7/26/2000 6:00 PM nundc QC code set to 7 calibration carryover? No data were flagged by STI at the Stafford, CT PAMS site in 2001 No data were flagged by STI at the Hamden, CT PAMS site in 2000 and 2001 A-3

50 Table A-4. Samples flagged by STI at the Sherwood Island, CT PAMS site in 2000 (total = 8 samples). 7/26/2000 1:00 PM through 7/26/2000 8:00 PM nundc QC code set to 7 calibration carryover? No data were flagged by STI at the Sherwood Island, CT PAMS site in 2001 Table A-5. Samples flagged by STI at the Acadia, ME PAMS site in 2000 (total = 3130 samples). Page 1 of 2 5/1/ :00 AM through 9/30/ :00 PM 124tmb QC = 7 A-4 Odd high concentrations, possible contamination prior to the GC odd high styr and ethan concentrations, likely seasonal effect and valid odd sloping ethan conc., likely seasonal effect and valid 5/1/ :00 AM through 6/21/2000 5:00 PM Record QC=7 6/21/2000 5:00 PM through 7/3/2000 7:00 AM Ethan QC=7 5/1/2000 1:00 PM through 5/1/2000 4:00 PM nundc QC code set to 7 calibration carryover 5/8/2000 1:00 PM through 5/8/2000 4:00 PM nundc QC code set to 7 calibration carryover 6/1/2000 2:00 PM through 6/1/2000 5:00 PM nundc QC code set to 7 calibration carryover 6/5/2000 2:00 PM through 6/5/2000 5:00 PM nundc QC code set to 7 calibration carryover 6/8/2000 1:00 PM through 6/8/2000 4:00 PM nundc QC code set to 7 calibration carryover 6/12/2000 1:00 PM through 6/12/2000 4:00 PM nundc QC code set to 7 calibration carryover 6/15/2000 2:00 PM through 6/15/2000 5:00 PM nundc QC code set to 7 calibration carryover 6/30/2000 1:00 PM through 6/30/2000 4:00 PM nundc QC code set to 7 calibration carryover 7/3/2000 1:00 PM through 7/3/2000 4:00 PM nundc QC code set to 7 calibration carryover 7/18/2000 1:00 PM through 7/18/2000 4:00 PM nundc QC code set to 7 calibration carryover 7/21/ :00 AM through 7/21/2000 2:00 PM nundc QC code set to 7 calibration carryover 7/24/ :00 PM through 7/24/2000 6:00 PM nundc QC code set to 7 calibration carryover 8/7/2000 3:00 PM through 8/7/2000 6:00 PM nundc QC code set to 7 calibration carryover 8/10/2000 4:00 PM through 8/10/2000 7:00 PM nundc QC code set to 7 calibration carryover

51 Table A-5. Samples flagged by STI at the Acadia, ME PAMS site in 2000 (total = 3130 samples). Page 2 of 2 8/14/2000 2:00 PM through 8/14/2000 5:00 PM nundc QC code set to 7 calibration carryover 8/17/2000 2:00 PM through 8/17/2000 5:00 PM nundc QC code set to 7 calibration carryover 8/18/2000 1:00 PM through 8/18/2000 7:00 PM nundc QC code set to 7 calibration carryover 9/5/2000 1:00 PM through 9/5/2000 3:00 PM nundc QC code set to 7 calibration carryover 9/14/2000 1:00 PM through 9/14/2000 3: 00 PM nundc QC code set to 7 calibration carryover Table A-6. Samples flagged by STI at the Acadia, ME PAMS site in 2001 (total = 3040 samples). 5/3/ :00 AM through 124tmb QC = 7 9/30/ :00 PM 6/20/ :00 AM through 7/28/2000 2:00 PM 24dmp QC=7 Odd high concentrations, possible contamination prior to the GC odd high 24dmp concentrations, not contamination odd benzene and ethane concentrations, high baselines; likely seasonal effect and valid 5/3/ :00 AM through 7/25/2001 7:00 AM record QC=7 5/17/2001 1:00 PM through 5/17/2001 4:00 PM nundc QC code set to 7 calibration carryover 6/21/ :00 PM through 6/21/2001 3:00 PM nundc QC code set to 7 calibration carryover 7/9/ :00 PM through 7/9/2000 3:00 PM nundc QC code set to 7 calibration carryover 7/17/ :00 AM through 7/17/2001 2:00 PM nundc QC code set to 7 calibration carryover 7/20/2001 1:00 PM through 7/20/2001 4:00 PM nundc QC code set to 7 calibration carryover 8/17/ :00 AM through 8/17/ :00 PM nundc QC code set to 7 calibration carryover 9/13/2001 1:00 PM through 9/13/2001 5:00 PM nundc QC code set to 7 calibration carryover 9/27/2001 2:00 PM through 9/27/2001 5:00 PM nundc QC code set to 7 calibration carryover A-5

52 Table A-7. Samples flagged by STI at the Cape Elizabeth, ME PAMS site in 2000 (total = 106 samples). 5/4/2000 2:00 PM through 5/4/2000 4:00 PM Nundc QC=7 calibration carryover 5/13/2000 1:00 PM through 5/13/2000 3:00 PM Nundc QC=7 calibration carryover 5/16/2000 3:00 PM through 5/16/2000 6:00 PM Nundc QC=7 calibration carryover 5/18/2000 1:00 PM through 5/18/2000 3:00 PM Nundc QC=7 calibration carryover 5/22/2000 1:00 PM through 5/22/2000 3:00 PM Nundc QC=7 calibration carryover 5/26/2000 4:00 PM through 5/26/2000 7:00 PM Nundc QC=7 calibration carryover 6/5/2000 4:00 PM through 6/5/2000 6:00 PM nundc and ndec QC=7 calibration carryover 6/15/2000 3:00 PM through 6/15/2000 5:00 PM Nundc QC=7 calibration carryover 6/28/2000 3:00 PM through 6/28/2000 5:00 PM Nundc QC=7 calibration carryover 7/20/2000 2:00 PM through 7/20/2000 4:00 PM Nundc QC=7 calibration carryover 9/14/ :00 PM through Not calibration carryover; appears to 9/15/2000 1:00 AM nundc and 123tmb QC=7 be real (but odd) 9/22/2000 2:00 PM through 9/22/2000 4:00 PM nundc and ndec QC=7 calibration carryover Table A-8. Samples flagged by STI at the Cape Elizabeth, ME PAMS site in 2001 (total = 15 samples). 7/2/2001 3:00 PM through 7/2/2001 6:00 PM Nundc, ndec and 123tmb QC=7 calibration carryover 7/26/2001 1:00 PM through 7/26/2001 3:00 PM Nundc, ndec, 123tmb and pdeben QC=7 calibration carryover A-6

53 Table A-9. Samples flagged by STI at the Kittery, ME PAMS site in 2000 (total = 2 samples). possible misidentification of toluene 5/29/2000 1:00 record QC=7 and 2mhep 8/10/ :00 tnmoc QC=7 tnmoc=1.55, wt% will be incorrect 8/21/ :00 tnmoc QC=7 tnmoc=1.39, wt% will be incorrect Table A-10. Samples flagged by STI at the Kittery, ME PAMS site in 2001 (total = 4 samples). 7/17/ :00 PM through 3:00 PM Ndec QC=7 calibration carryover? Table A-11. Samples flagged by STI at the Agawam, MA PAMS site in 2000 (total=1). 7/19/ :00 PMtnmoc QC=7 tnmoc reported as 0 Table A-12. Samples flagged by STI at the Borderland, MA PAMS site in 2000 (total=1). odd high concentration, 7/13/ :00 PM124tmb QC=7 other species low A-7

54 Table A-13. Samples flagged by STI at the Chicopee, MA PAMS site in 2000 (total = 997 samples). 6/28/2000 1:00 AM through 8/31/ :00 PM Styr QC = 7 High detection limit possible misidentification 8/14/2000 8:00 Cyhxa and benz QC = 7 between cyhxa and benz possible misidentification 7/28/2000 4:00 Cyhxa and benz QC = 7 between cyhxa and benz possible misidentification 8/29/2000 7:00 Cyhxa and benz QC = 7 between cyhxa and benz possible misidentification 8/14/ :00 Cyhxa and benz QC = 7 between cyhxa and benz Table A-14. Samples flagged by STI at the Lynn, MA PAMS site in 2000 (total = 1944 samples). 6/15 12:00 AM through 7/12 11:00 PM 22dmb QC = 7 high detection limit or column contamination 6/1 12:00 AM through 8/31 11:00 PM 124tmb QC = 7 high detection limit or column contamination 6/15 12:00 AM through 7/12 11:00 PM Ndec and nundc QC = 7 high detection limit or column contamination 6/20/ :00 cyhxa QC=7 odd high cyhxa with benz<1 7/3/ :00 cyhxa QC=7 odd high cyhxa with benz<1 7/14/2000 8:00 cyhxa QC=7 odd high cyhxa with benz<3 7/3/ :00 cyhxa QC=7 odd high cyhxa with benz=0 6/22/2000 9:00 cyhxa QC=7 odd high cyhxa with benz<2 7/12/ :00 cyhxa QC=7 odd high cyhxa with benz=0 8/28/ :00 ebenz QC=7 odd high ebenz with low 124tmb A-8

55 Table A-15. Samples flagged by STI at the Newbury, MA PAMS site in 2000 (total = 1364 samples). 6/29 3:00 PM through 8/31 11:00 PM styr QC = 7 high detection limit Table A-16. Samples flagged by STI at the Truro, MA PAMS site in /2 2:00 PM through 8/31 11:00 PM styr QC = 7 high detection limit 6/5/ :00 124tmb QC=7 odd high concentration, other species low Table A-17. Samples flagged by STI at the Ware, MA PAMS site in 2000 (total = 1058 samples). 7/13 1:00 PM through 8/31 11:00 PM styr QC = 7 high detection limit 6/26/ :00 123tmb QC=7 odd high single concentration 6/27/ :00 123tmb QC=7 odd high single concentration 6/29/ :00 123tmb QC=7 odd high single concentration 6/21/ :00 123tmb QC=7 odd high single concentration 6/21/ :00 123tmb QC=7 odd high single concentration 6/21/2000 5:00 123tmb QC=7 odd high single concentration 6/10/2000 9:00 123tmb QC=7 odd high single concentration 6/10/ :00 123tmb QC=7 odd high single concentration 6/13/ :00 123tmb QC=7 odd high single concentration 6/7/2000 7:00 123tmb QC=7 odd high single concentration 6/27/ :00 2mpna and 3mpna QC=7 3mpna and 2mpna appear to reported together as 2mpna 7/27/2000 4:00 PM through 7/27/2000 6:00 PM Ndec and nundc QC=7 possible calibration carryover 6/30/2000 9:00 cyhxa QC= 7 odd high concentration with low benz 6/29/ :00 cyhxa QC=7 odd high concentration with low benz 6/29/ :00 cyhxa QC=7 odd high concentration with low benz A-9

56 Table A-18. Samples flagged by STI at the Brentwood, NH PAMS site in 2000 (total = 70 samples). 6/1/ :00 AM through 8/31/ :00 PM metol, petol QC = 7 misidentification 8/24/ :00 Tnmoc= 7 tnmoc=1.59, wt% calculation would be wrong 7/21/2000 4:00 Tnmoc=7 tnmoc=1.14, wt% calculation would be wrong Table A-19. Samples flagged by STI at the Brentwood, NH PAMS site in 2001 (total=1). 8/24/ :00Record QC=7 high unidentified (>80% tnmoc) Table A-20. Samples flagged by STI at the Camden, NJ PAMS site in 2000 (total=15 samples). 8/23/ :00 propa QC=7 extremely high concentration spike, other species low 8/19/ :00 isbta QC=7 High isbta without high nbuta 23dmb and 3mpna 3mpna and 23dmb reported together as 8/10/ :00 QC=7 23dmb 23dmb and 3mpna 3mpna and 23dmb reported together as 8/24/2000 1:00 QC=7 23dmb 8/11/2000 8:00 uidvoc QC code set to 7 high unidentified 8/19/ :00 isbta QC code set to 7 High isbta with very low nbuta 8/24/2000 1:00 ispna QC code set to 7 High ispna with very low npnta npnta QC code set 8/7/ :00 to 7 High npnta with very low ispna 8/10/ :00 Record QC code set to 7 ethan=0, bz>5, possible cold trap problem 8/15/ :00 PM through 8/15/2000 1:00 PM nundc QC=7 possible calibration carryover 8/17/ :00 AM through Ndec, 123tmb and 8/17/ :00 PM nundc QC=7 possible calibration carryover 8/31/ :00 AM through 8/31/2000 1:00 PM nundc QC=7 possible calibration carryover A-10

57 Table A-21. Samples flagged by STI at the Camden, NJ PAMS site in 2001 (total = 3 samples). 6/4/2001 0:00 ethyl QC=7 high ethylene with other species low 8/27/ :00 nundc QC=7 possible calibration carryover 8/27/ :00 nundc QC=7 possible calibration carryover Table A-22. Samples flagged by STI at the Rider College, NJ PAMS site in 2000 (total = 28 samples). 8/5/ :00 Record QC=7 high unidentified 6/5/2000 2:00 npnta QC=7 high npnta with low ispna 6/15/ :00 AM through 6/15/2000 1:00 PM Ndec, 123tmb and nundc QC=7 possible calibration carryover 6/22/ :00 AM through 6/22/2000 1:00 PM Ndec, 123tmb and nundc QC=7 possible calibration carryover 7/13/ :00 AM through 713/2000 1:00 PM nundc and ndec QC=7 possible calibration carryover 7/20/ :00 AM through 7/20/2000 1:00 PM nundc and ndec QC=7 possible calibration carryover 8/10/ :00 AM through 8/10/2000 3:00 PM nundc and ndec QC=7 possible calibration carryover 8/17/ :00 AM through 8/17/2000 1:00 PM nundc and ndec QC=7 possible calibration carryover 8/24/ :00 AM through 8/24/2000 1:00 PM nundc and ndec QC=7 possible calibration carryover 8/31/ :00 AM through 8/31/2000 2:00 PM nundc and ndec QC=7 possible calibration carryover A-11

58 Table A-23. Samples flagged by STI at the Rider College, NJ PAMS site in 2001 (total = 173 samples). 8/16/ :00 AM through 8/23/2000 8:00 AM Record QC=7 8/30/ TNMOC and PAMS QC=7 6/11/2000 8:00 PM through 6/12/2000 3:00 AM Tolu and 234tmp QC = 7 odd fingerprint: extremely high concentrations of ethyl tailing off, other species low pamshc>tnmoc, bad calculation misidentification of tolu and 234tmp? misidentification of tolu and 234tmp? 6/13/ :00 AM Benz and cyhxa QC = 7 6/18/ :00 AM through 6/18/2000 2:00 PM nundc and ndodc QC = 7 calibration carryover? Table A-24. Samples flagged by STI at the New Brunswick, NJ PAMS site in 2000 (total=2). 6/30/ :00 23dmp QC code set to 7 unusually high concentration, other species low unusually high concentration, other 8/17/2000 1:00 224tmp QC code set to 7 species low Table A-25. Samples flagged by STI at the New Brunswick, NJ PAMS site in /27/ :00 Nnon and ndec QC code set to 7 odd fingerprint: high C9-C10, other species low 6/4/ :00 Record QC code set to 7 extremely high unidentified odd fingerprint: high conc of C9-C12, other 8/22/ :00 Record QC code set to 7 species low A-12

59 Table A-26. Samples flagged by STI at the Bronx, NY PAMS site in 2000 (total = 106 samples). Page 1 of 2 5/17/ :00 Record QC code set to 7 extremely high unid (>90%) 5/19/ :00 Record QC code set to 7 extremely high unid (>90%) 5/29/ :00 Record QC code set to 7 extremely high unid (>90%) 6/7/ :00 through 13:00 Record QC code set to 7 extremely high unid (>90%) 6/14/ :00 through 15:00 Record QC code set to 7 extremely high unid (>90%) 7/5/ :00 Record QC code set to 7 extremely high unid (>90%) 7/6/ :00 through 16:00 Record QC code set to 7 extremely high unid (>90%) 7/12/ :00 through 17:00 Record QC code set to 7 extremely high unid (>90%) 7/13/ :00 Record QC code set to 7 extremely high unid (>90%) 7/13/ :00 Record QC code set to 7 extremely high unid (>90%) 7/14/ :00 Record QC code set to 7 extremely high unid (>90%) 8/1/ :00 through 15:00 Record QC code set to 7 extremely high unid (>90%) 8/9/ :00 Record QC code set to 7 extremely high unid (>90%) 8/10/ :00 through 16:00 Record QC code set to 7 extremely high unid (>90%) 8/17/ :00 Record QC code set to 7 extremely high unid (>90%) 8/22/ :00 Record QC code set to 7 extremely high unid (>90%) 9/7/ :00 Record QC code set to 7 extremely high unid (>90%) 6/14/ :00 Record QC code set to 7 extremely high unid (>97%) 6/15/ :00 Record QC code set to 7 extremely high unid (>97%) 9/4/ :00 through 22:00 Record QC code set to 7 TNMOC <2 5/1/ :00 Record QC code set to 7 unusually high TNMOC 5/3/ :00 Record QC code set to 7 unusually high TNMOC 5/5/ :00 Record QC code set to 7 unusually high TNMOC 5/7/ :00 Record QC code set to 7 unusually high TNMOC 5/9/ :00 Record QC code set to 7 unusually high TNMOC 5/11/ :00 Record QC code set to 7 unusually high TNMOC 5/13/ :00 Record QC code set to 7 unusually high TNMOC 5/15/ :00 Record QC code set to 7 unusually high TNMOC 5/21/ :00 Record QC code set to 7 unusually high TNMOC 5/23/ :00 Record QC code set to 7 unusually high TNMOC 5/25/ :00 Record QC code set to 7 unusually high TNMOC 5/27/ :00 Record QC code set to 7 unusually high TNMOC 5/31/ :00 Record QC code set to 7 unusually high TNMOC 7/5/ :00 Record QC code set to 7 unusually high TNMOC 6/3/2000 1:00 PM through 3:00 PM Nundec QC=7 Calibration carryover? 6/5/2000 1:00 PM through 3:00 PM Nundec QC=7 Calibration carryover? 6/7/2000 4:00 PM through 7:00 PM Nundec QC=7 Calibration carryover? 6/13/2000 1:00 PM through 5:00 PM Nundec QC=7 Calibration carryover? 6/17/2000 4:00 PM through 8:00 PM Nundec and ndec QC=7 Calibration carryover? 6/19/2000 3:00 PM through 6:00 PM Nundec QC=7 Calibration carryover? 6/21/2000 2:00 PM through 6:00 PM Nundec QC=7 Calibration carryover? 6/23/2000 3:00 PM through 6:00 PM Nundec QC=7 Calibration carryover? 6/27/2000 5:00 PM through 7:00 PM Nundec QC=7 Calibration carryover? 8/12/2000 8:00 PM through 11:00 PM Nundec QC=7 Calibration carryover? A-13

60 Table A-26. Samples flagged by STI at the Bronx, NY PAMS site in 2000 (total = 106 samples). Page 2 of 2 8/14/ :00 PM through 8/15/2000 1:00 AM Nundec QC=7 Calibration carryover? 8/16/ :00 PM through 8/17/2000 1:00 AM Nundec QC=7 Calibration carryover? 8/19/2000 1:00 AM through 4:00 AM Nundec QC=7 Calibration carryover? Table A-27. Samples flagged by STI at the Bronx, NY PAMS site in 2001 (total = 2 samples). 9/28/2001 1:00 AMcyhxa and benz QC=7 possible misidentification of cyhxa and benz Table A-28. Samples flagged by STI at the Queens, NY PAMS site in 2000 (total = 281 samples). 8/3/ through 8/4/ Nnon, petol, 135tmb, oetol, ndec, 123tmb, mdeben, pdeben and nundc QC=7 8/4/ through 2100 Nnon, petol, 135tmb, oetol, ndec, 123tmb, mdeben, pdeben and nundc QC=7 Page 1 of 2 odd fingerprint: high conc of nnon-nundc odd fingerprint: high conc of nnon-nundc 7/21/2000 9:00 Record QC code set to 7 TNMOC=0 9/26/2000 8:00 Record QC code set to 7 TNMOC=0 6/29/ :00 3mpna and 2mpna QC=7 strange outlier of 2mpna and 3mpna 5/16/ :00 PM through 5/17/2000 2:00 AM Nundec QC=7 Calibration carryover? 5/20/2000 5:00 PM through 7:00 PM Nundec QC=7 Calibration carryover? 5/22/2000 6:00 PM through 8:00 PM Nundec QC=7 Calibration carryover? 5/24/2000 7:00 PM through 9:00 PM Nundec QC=7 Calibration carryover? 5/26/2000 5:00 PM through 7:00 PM Nundec QC=7 Calibration carryover? 5/28/2000 7:00 PM through 9:00 PM Nundec QC=7 Calibration carryover? 5/30/2000 9:00 PM through 11:00 PM Nundec QC=7 Calibration carryover? 6/6/ :00 AM through 3:00 AM Nundec QC=7 Calibration carryover? 6/8/ :00 AM through 3:00 AM Nundec QC=7 Calibration carryover? 6/10/2000 2:00 AM through 5:00 AM Nundec QC=7 Calibration carry over? A-14

61 Table A-28. Samples flagged by STI at the Queens, NY PAMS site in 2000 (total = 281 samples). Page 2 of 2 6/12/2000 2:00 AM through 5:00 AM Nundec QC=7 Calibration carryover? 6/14/ :00 AM through 3:00 AM Nundec QC=7 Calibration carryover? 6/16/ :00 AM through 3:00 AM Nundec QC=7 Calibration carryover? 6/18/2000 1:00 AM through 5:00 AM Nundec QC=7 Calibration carryover? 6/23/ :00 AM through 3:00 AM Nundec QC=7 Calibration carryover? 6/25/ :00 AM through 3:00 AM Nundec QC=7 Calibration carryover? 6/29/ :00 AM through 3:00 AM Nundec QC=7 Calibration carryover? 7/6/ :00 AM through 4:00 AM Nundec QC=7 Calibration carryover? 7/8/2000 3:00 AM through 5:00 AM Nundec QC=7 Calibration carryover? 7/10/2000 4:00 AM through 6:00 AM Nundec QC=7 Calibration carryover? 7/12/2000 5:00 AM through 7:00 AM Nundec QC=7 Calibration carryover? 7/14/2000 4:00 AM through 6:00 AM Nundec QC=7 Calibration carryover? 7/16/2000 3:00 AM through 5:00 AM Nundec QC=7 Calibration carryover? 7/27/2000 4:00 AM through 6:00 AM Nundec QC=7 Calibration carryover? 7/29/2000 5:00 AM through 7:00 AM Nundec QC=7 Calibration carryover? 8/2/2000 5:00 AM through 7:00 AM Nundec QC=7 Calibration carryover? 7/31/2000 6:00 AM through 8:00 AM Nundec QC=7 Calibration carryover? 8/13/2000 1:00 AM through 3:00 AM Nundec QC=7 Calibration carryover? 8/17/2000 1:00 AM through 3:00 AM Nundec QC=7 Calibration carryover? 8/13/2000 2:00 AM through 4:00 AM Nundec QC=7 Calibration carryover? 8/23/2000 2:00 AM through 4:00 AM Nundec QC=7 Calibration carryover? 8/31/2000 4:00 AM through 6:00 AM Nundec QC=7 Calibration carryover? 9/6/2000 3:00 AM through 5:00 AM Nundec QC=7 Calibration carryover? 8/29/2000 4:00 AM through 6:00 AM Nundec QC=7 Calibration carryover? A-15

62 Table A-29. Samples flagged by STI at the Queens, NY PAMS site in 2001 (total = 10 samples). odd fingerprint - high tolu, 2&3nhexa, nhept, 23dmp, 7/16/2001 7:04Record QC code set to 7 224tmp,mcyhex odd fingerprint - high ebenz, m/p/oxyl, C9-11, petol, oetol, 8/28/2001 7:54Record QC code set to 7 123tmb, mbeden odd fingerprint - high ebenz, m/p/oxyl, C9-11, petol, oetol, 8/28/2001 9:54Record QC code set to 7 123tmb, mbeden 8/6/2001 7:02Record QC code set to 7 odd fingerprint - very high C10-11, mdeben 8/6/2001 7:02Record QC code set to 7 odd fingerprint - very high C10-11, mdeben 8/16/2001 6:59Record QC code set to 7 odd fingerprint - very high C10-11, mdeben 8/17/2001 5:59mdeben QC code set to 7 extremely high mdeben (>100ppbC) with other species low 8/17/2001 6:59mdeben QC code set to 7 extremely high mdeben (>100ppbC) with other species low 8/17/2001 7:59mdeben QC code set to 7 extremely high mdeben with other species low 8/28/2001 7:54Ebenz and 124tmb QC=7 high ebenz with low 124tmb Table A-30. Samples flagged by STI at the Providence, RI PAMS site in /29/ :00Record QC code set to 7 very high unidentified 0 concentrations C2-C5 (appears to be from an error in 7/19/ :00Record QC code set to 7 the original AIRS file) Table A-31. Samples flagged by STI at the Providence, RI PAMS site in 2001 (total=505 samples). 7/29/ :00 Record QC code set to 7 extremely high unidentified 6/1/ :00 AM through 7/30/ :00 PM Mpxyl and oxyl QC = 7 m/p -xylenes data in AIRS appear to be a factor of 10 too low (possible decimal point indicator problem) No data were flagged by STI at the West Greenwich, RI PAMS site in 2000 Table A-32. Samples flagged by STI at the West Greenwich, RI PAMS site in /8/ Ispr QC=7 Strange high concentration A-16

63 APPENDIX B SPECIES ABBREVIATIONS B-1

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65 Table B-1. AIRS code, abbreviation, hydrocarbon name, and species group (O=olefin, P=paraffin, A=aromatic). Page 1 of 2 Species AIRS code Abbreviation Hydrocarbon Group acety Acetylene O ethyl Ethylene O ethan Ethane P prpyl Propylene O propa Propane P isbta Isobutane P bute 1-Butene O nbuta n-butane P t2bte trans-2-butene O c2bte cis-2-butene O mlbe 3-Methyl-1-Butene O ispna Isopentane P pnte 1-Pentene O npnta n-pentane P ispre Isoprene O t2pne trans-2-pentene O c2pne cis-2-pentene O m2be 2-Methyl-2-Butene O dmb 2,2-Dimethylbutane P cypne Cyclopentene O mlpe 4-Methyl-1-Pentene O cypna Cyclopentane P dmb 2,3-Dimethylbutane P mpna 2-Methylpentane P mpna 3-Methylpentane P m1pe 2-Methyl-1-Pentene O nhexa n-hexane P t2hex trans-2-hexene O c2hex cis-2-hexene O mcpna Methylcyclopentane P dmp 2,4-Dimethylpentane P benz Benzene A cyhxa Cyclohexane P mhxa 2-Methylhexane P dmp 2,3-Dimethylpentane P mhxa 3-Methylhexane P tmp 2,2,4-Trimethylpentane P nhept n-heptane P mcyhx Methylcyclohexane P tmp 2,3,4-Trimethylpentane P tolu Toluene A B-3

66 Table B-1. AIRS code, abbreviation, hydrocarbon name, and species group (O=olefin, P=paraffin, A=aromatic). Page 2 of 2 Species AIRS code Abbreviation Hydrocarbon Group mhep 2-Methylheptane P mhep 3-Methylheptane P noct n-octane P ebenz Ethylbenzene A m/pxy m/p-xylene A mxyl m-xylene A pxyl p-xylene A styr Styrene A oxyl o-xylene A nnon n-nonane P ispbz Isopropylbenzene A npbz n-propylbenzene A apine alpha-pinene O tmb 1,3,5-Trimethylbenzene A tmb 1,2,4-Trimethylbenzene A bpine beta-pinene O oetol o-ethyltoluene A metol m-ethyltoluene A petol p-ethyltoluene A mdeben m-diethylbenzene A pdeben p-diethylbenzene A tmb 1,2,3-trimethylbenzene A ndec n-decane P nundc n-undecane P tnmoc Total Non-Methane Organic Compounds form Formaldehyde C aceta Acetaldehyde C acet Acetone C buta 1,3-butadiene O m1bte 2-methyl-1-butene O ethex 3-ethylhexane P mhex 2,5-dimethylhexane P hex24m 2,4-dimethylhexane P hex23m 2,3-dimethylhexane P propa22m 2,2-dimethylpropane P ibute Isobutene O mcpne Methylcyclopentene O mhpte 4-Methylheptane P pamshc Sum PAMS Target Species B-4