Attainment and Exceedances of Air Quality Standards
According to the Code of Federal Regulations (Title 40, Part 58), every state must create an air monitoring network to ensure effective air quality assessment This network includes National Air Monitoring Stations (NAMS) situated in urban areas, which are strategically placed based on population density, forming a reliable nationwide database Additionally, the State and Local Air Monitoring Stations (SLAMS) network encompasses NAMS and other monitoring sites, offering a thorough evaluation of air quality across various regions.
The Air Assessment Branch (AAB) of the Massachusetts Department of Environmental Protection (MADEP) is responsible for gathering ambient air quality data across the state In 2002, AAB managed a network of 40 publicly funded monitoring stations situated in 25 cities and towns Additionally, AAB supervised a privately funded industrial monitoring network consisting of four stations located in the Boston area.
MADEP submits ambient air quality data to the Aerometric Information Retrieval System (AIRS), a computer-based repository of national air quality information administered by the U.S
Why is Air Quality Data Collected?
The ambient air quality data is used for the following purposes:
•to verify compliance with National Ambient Air Quality Standards;
•to support development of policies and regulations designed to reduce ambient air pollution;
•to assess the effectiveness of existing air pollution control strategies;
•to provide aerometric data for long-term trend analysis and special research; and
•to fulfill USEPA reporting requirements for ambient air quality data.
The parameters monitored by the Air Assessment Branch fall into the following categories:
Criteria pollutants are subject to National Ambient Air Quality Standards (NAAQS) The seven criteria pollutants are:
Non-criteria pollutants have no established national standards These pollutants are:
• total reactive oxidized nitrogen (NOy)
• volatile organic compounds (VOC) – ozone precursors and reaction product chemicals
• wind speed/wind direction (WS/WD)
• upper air wind and temperature
Monitoring locations for pollutants are strategically chosen to gather data for diverse purposes Some sites are positioned in "hot spots" with anticipated high concentrations, while others reflect broader land area conditions The scale of representation for each monitoring site is influenced by the surrounding topography and the proximity of pollutant sources.
Massachusetts has a comprehensive network of monitors strategically placed across the state to accurately measure pollutant concentrations Section III provides detailed data summaries for each pollutant, along with maps indicating the locations of these monitoring stations Additionally, a site directory is included, listing the various monitors at each site The accompanying map illustrates the cities and towns in Massachusetts that had monitoring stations in 2002.
For more details regarding this report, please reach out to the Air Assessment Branch For inquiries related to other air quality issues, you can contact the Massachusetts Department of Environmental Protection’s (MADEP) Division of Planning and Evaluation in Boston or a local MADEP regional office The relevant addresses are provided below.
MADEP - NERO (NORTHEAST/METRO BOSTON)
One Winter Street Boston, MA 02108
Division of Planning and Evaluation One Winter Street
William X Wall Experiment Station Lawrence, MA 01843
(978) 975-1138 Thomas McGrath: Acting Branch Chief
Information about MADEP’s various programs and this report are available on the internet from MADEP’s web site (www.mass.gov/dep) The USEPA maintains a web site
(www.epa.gov/air/data) that has air quality information from all the states.
National Ambient Air Quality Standards
Primary Standards – designed to protect public health against adverse health effects with a margin of safety.
Secondary Standards - designed to protect against damage to crops, vegetation, and buildings
POLLUTANT AVERAGING TIME* PRIMARY SECONDARY
Annual Arithmetic Mean 0.03 ppm (80 ug/m³) None
SO 2 24-Hour 0.14 ppm (365 ug/m³) None
CO 8-Hour 9 ppm (10 mg/m³) Same as Primary Standard
1-Hour 35 ppm (40 mg/m³) Same as Primary Standard
O 3 1-Hour 0.12 ppm (235 ug/m³) Same as Primary Standard
8-Hour 0.08 ppm (157 ug/m³) Same as Primary Standard
• The 1-hour standard is met when the daily maximum 1-hour concentration does not exceed 0.12 ppm at any one monitor on more than 3 days over any 3 year period.
• The 8-hour standard is met when the 3-year average of the 4th-highest daily maximum 8-hour average does not exceed 0.08 ppm at any one monitor
Mean 1.5 ug/m³ Same as Primary Standard
NO 2 Annual Arithmetic Mean 0.053 ppm 100 ug/m³ Same as Primary Standard
15.0 ug/m³ Same as Primary Standard
2.5 microns in size 24-Hour 65 ug/m³ Same as Primary Standard
The annual standard for PM 2.5 is achieved when the three-year average of quarterly mean concentrations is 15 µg/m³ or lower In cases where spatial averaging is applied, the annual average from all monitoring stations in the area can be included in the calculation of the three-year mean.
• The 24-hour standard is met when the 98th percentile value is less than or equal to 65 ug/m³ (3-year average).
50 ug/m³ Same as Primary Standard
10 microns in size 24-Hour 150 ug/m³ Same as Primary Standard
• The PM 10 standard is based upon estimated exceedance calculations described in 40 CFR Part 50, Appendix K.
• The annual standard is met if the estimated annual arithmetic mean does not exceed 50 ug/m 3
The 24-hour air quality standard is met if the estimated number of days in a calendar year with pollutant levels exceeding 150 µg/m³ does not exceed one day annually.
* Standards based upon averaging times other than the annual arithmetic mean must not be exceeded more than once a year.
Pollutant Health Effects and Sources
Ground-level ozone (O3) is often mistaken for stratospheric ozone, but they have very different effects While stratospheric ozone plays a crucial role in protecting us by filtering harmful ultraviolet radiation from the sun, ground-level ozone poses significant health and environmental risks This report focuses specifically on the issues associated with ground-level ozone.
• O3 irritates mucous membranes This causes reduced lung function, nasal congestion, and throat irritation, and reduced resistance to infection.
• O3 is toxic to vegetation, inhibiting growth and causing leaf damage.
• O3 weakens materials such as rubber and fabrics.
Ozone (O3) is uniquely formed through reactions between various pollutants under intense sunlight, particularly during the summer months The complexity of these reactions and the time required for their completion lead to the accumulation of ground-level ozone concentrations significantly far from the original sources of the precursor pollutants.
• Sources of ground-level O3 precursors, nitrogen oxides and hydrocarbons, include motor vehicles and power plants.
• CO reacts in the bloodstream with hemoglobin, reducing oxygen carried to organs and tissues.
• Symptoms of high CO exposure include shortness of breath, chest pain, headaches, confusion, and loss of coordination The health threat is most severe for those with cardiovascular disease.
• High levels of CO are possible near parking lots and city streets with slow-moving cars, particularly during peak traffic times.
• Motor vehicle emissions are the largest source of CO, which is produced from incomplete combustion of carbon in fuels.
• SO2 combines with water vapor to form acidic aerosols harmful to the respiratory tract, aggravating symptoms associated with lung diseases such as asthma and bronchitis.
• SO2 is a primary contributor to acid deposition Impacts of acid deposition include: acidification of lakes and streams, damage to vegetation, damage to materials, degradation of visibility.
• SO2 is a product of fuel combustion (e.g., burning coal and oil) Sources include heat and power generation facilities, and petroleum refineries.
• NO2 is formed from the oxidation of nitric oxide (NO) Major sources of NO are fuel combustion, heating and power plants, and motor vehicles.
Particulate Matter (PM10 and PM2.5)
Particulate matter refers to tiny airborne particles, including dust, dirt, soot, smoke, and liquid droplets Fine particulate matter, primarily measuring below 2.5 microns, can originate from direct emissions and also form in the atmosphere through chemical reactions involving gaseous pollutants.
The particle sizes of 2.5 and 10 microns are monitored, indicating the concentration of PM2.5 particles in the air To illustrate, several thousand PM2.5 particles could fit on a single period at the end of this sentence.
The tiny size of particles enables them to penetrate the human respiratory system, leading to long-term accumulation in the lungs, which can impair breathing and trigger respiratory symptoms Furthermore, the smallest particles can migrate from the lungs into the circulatory system, potentially causing cardiovascular issues and adverse effects from the toxic substances they contain.
• Particulate matter causes soiling and corrosion of materials.
• Particulate matter contributes to atmospheric haze that degrades visibility.
• Sources include industrial process emissions, motor vehicles, incinerators, heat and power plants.
• Lead is an elemental metal.
Airborne lead emissions have significantly decreased due to the widespread adoption of unleaded gasoline, which has largely replaced motor vehicles as the primary source of lead pollution However, lead smelters and battery manufacturing plants continue to contribute to lead emissions in the environment.
• Exposure to lead may occur by inhalation or ingestion of food, water, soil or dust particles.
• Children, infants, and fetuses are more susceptible to the effects of lead exposure.
• Lead causes mental retardation, brain damage, and liver disease It may be a factor in high blood pressure and damages the nervous system
Public and Industrial Network Descriptions
The Air Assessment Branch operates a public ambient air monitoring network.
• 25 cities and towns with monitoring stations
Continuous monitors measure the air quality 24 hours per day The data is reported as hourly means.
• Criteria pollutant monitors measure pollutants for which National Ambient Air Quality Standards (NAAQS) have been set.
15 – NO 2 (nitrogen dioxide) NO (nitrogen oxide) and NO x (total nitrogen oxides) are also measured by these monitors.
• Meteorological monitors track weather conditions.
12 – WS/WD (wind speed/wind direction)
1 – Upper Meteorology – this monitor measures WS/WD and TEMP at various altitudes This aids in the analysis of pollutant transport.
3 – NO y (Total Reactive Oxidized Nitrogen)
3 – PAMS (Photochemical Assessment Monitoring Station) These monitors measure VOCs (volatile organic compounds).
3 – PM 2.5 (particulate matter – 2.5 microns, BAM)
Acid deposition is monitored through the analysis of precipitation for conductivity and harmful acidic compounds In Waltham, a monitoring station is part of the National Atmospheric Deposition Program (NADP), alongside two additional NADP monitors located in Truro and Ware, which are not managed by the Massachusetts Department of Environmental Protection (MADEP).
Note: The number of public sites described above was consolidated to 28 stations in 21 communities after December
31, 2002, in response to the results of a network review that was driven by resource and data need considerations Further network review is continuing in view of emerging nationwide monitoring initiatives
Intermittent monitors collect discrete samples over designated time periods, which can occur daily, every third day, or every sixth day The gathered data is then averaged in intervals of either 3 hours or 24 hours.
• Criteria pollutant monitors measure pollutants that have National Ambient Air Quality Standards (NAAQS).
• Non-criteria pollutant monitors – pollutants measured do not have NAAQS.
3 – PAMS (photochemical assessment monitoring station) These monitors measure VOCs (volatile organic compounds).
2 – Toxics These monitors measure health-relevant VOCs.
2 – Speciation These monitors measure for PM 2.5 , nitrates, and organics
Industries monitor air quality and submit data under agreement with MADEP The data must be collected using quality assurance requirements established by MADEP and USEPA
• All are located in the Boston area
Continuous monitors measure the air quality 24 hours per day The data is averaged to provide 1-hour averages.
• Criteria pollutant monitors measure pollutants that have National Ambient Air Quality Standards (NAAQS).
1 – NO 2 (nitrogen dioxide) NO (nitrogen oxide) and NO x (total nitrogen oxides) are also measured by this monitor.
4– WS/WD (wind speed/wind direction)
Intermittent monitors take discrete samples for a specific time period These monitors sample every sixth day, and the data is averaged for a 24-hour interval.
Massachusetts Air Quality Data Summaries
Before the mid-1980s, Massachusetts struggled to meet carbon monoxide (CO) standards, but significant control programs led to a notable decrease in emissions The state last violated the CO National Ambient Air Quality Standards (NAAQS) in 1986 In 2000, the Massachusetts Department of Environmental Protection (MADEP) requested the U.S Environmental Protection Agency (USEPA) to re-designate Lowell, Springfield, Waltham, and Worcester as meeting CO standards due to consistent monitoring data showing levels below the standard With the successful re-designation of these cities in April 2002, Massachusetts achieved full compliance with CO standards statewide.
The National Ambient Air Quality Standards (NAAQS) for ozone include two key benchmarks: a historical standard of 0.12 parts per million (ppm) over one hour, which was in place for nearly 20 years until 1997, and a new, stricter standard of 0.08 ppm averaged over eight hours established by the USEPA Following this change, industry groups challenged the USEPA in court, but in February 2001, the U.S Supreme Court affirmed the agency's authority to set health-based standards Subsequently, in March 2002, the U.S Court of Appeals for the District of Columbia upheld these standards However, the USEPA has yet to designate ozone nonattainment areas for the new eight-hour standard due to delays caused by ongoing litigation from industry stakeholders.
MADEP monitors for both 1-hour and 8-hour ozone levels throughout the state.
Massachusetts has struggled with 1-hour ozone standard violations for many years, but recent control programs have led to significant improvements, resulting in a decline in both the frequency and severity of these exceedances From 1999 to 2002, the state was in violation of both the 1-hour and 8-hour ozone standards The USEPA is anticipated to announce the state's attainment status for the new 8-hour ozone standard in 2004, with expectations that Massachusetts will be classified as nonattainment.
PM2.5 - The Evolution of the Particulate Standard
On a periodic basis USEPA conducts a review of the national ambient air quality standards
The National Ambient Air Quality Standards (NAAQS) process involves compiling and scientifically assessing all available health and environmental effects data This information is rigorously reviewed by the scientific community, industry stakeholders, public interest groups, and the general public, alongside the Clean Air Scientific Advisory Committee (CASAC), which consists of independent experts mandated by Congress Following these assessments and considering CASAC's recommendations, the USEPA administrator determines whether revisions to the standards are warranted.
Over the years, the particulate matter standard has evolved in response to new research highlighting the health impacts of particulate matter There has been a growing emphasis on regulating smaller particles and enforcing stricter concentration limits, as studies have consistently shown that exposure to fine particulate matter is associated with negative health outcomes.
• 1970 – The standard was based on Total Suspended Particulates (TSP) The standards were set at 260 ug/m 3 (24-hours) and 75 ug/m 3 (annual geometric mean).
In 1987, the TSP standard was replaced by the PM10 standard, which focuses on particulate matter measuring 10 microns or smaller The established PM10 standards are set at 150 µg/m³ for a 24-hour period and 50 µg/m³ for the annual arithmetic mean.
In 1997, the PM2.5 standard, which regulates particulate matter measuring 2.5 microns or smaller, was established alongside the existing PM10 standard The PM2.5 limits were set at 65 micrograms per cubic meter for a 24-hour average and 15 micrograms per cubic meter for the annual arithmetic mean.
After the introduction of the new PM2.5 standard, industry groups initiated legal challenges against it Although the courts have supported the standard, its implementation has faced delays The USEPA is anticipated to designate attainment status for regions under the PM2.5 standard in 2004 or beyond.
It is not clear whether Massachusetts will attain the PM2.5 standard.
An O3 exceedance happens when daily ozone (O3) levels surpass the National Ambient Air Quality Standards (NAAQS) There are two specific O3 standards: the 1-hour standard, which is exceeded when hourly concentrations reach or exceed 0.125 ppm, and the 8-hour standard, which is exceeded when the 8-hour average concentration is equal to or greater than 0.085 ppm.
The Difference Between an Exceedance and a Violation
An exceedance of O3 standards does not automatically indicate a violation; instead, violations of the 1-hour and 8-hour standards are determined by analyzing 3-year averages of O3 data.
Violations of the 1-hour standard are determined using the number of expected exceedance days
An exceedance day is defined as a day when the 1-hour average ozone (O3) concentration exceeds the standard limit of 0.125 ppm Each monitoring site can only report one exceedance per day, which is determined by the hour with the highest average The concept of "expected exceedance days" encompasses both the actual exceedance days and instances of missing data.
A violation of the 1-hour ozone standard occurs when there are four or more days within a three-year period where the ozone levels reach or exceed 0.125 ppm This means that if the average number of exceedance days in that timeframe is greater than one, it indicates a breach of the 1-hour standard at that specific location.
To determine violations of the 8-hour ozone (O3) standard, the annual 4th-highest daily maximum 8-hour value is analyzed A violation occurs when the 3-year average of this value is equal to or exceeds 0.085 ppm This process involves ranking the daily 8-hour values from highest to lowest throughout the year and identifying the 4th-highest value for three consecutive years If the average of these values meets or surpasses the 0.085 ppm threshold, it indicates a violation of the 8-hour ozone standard at that specific location.
During 2002, there were five exceedance days and 22 exceedances of the 1-hour standard There were 30 exceedance days and 121 exceedances of the 8-hour standard
Using data from 2000–2002, five out of 15 sites violated the 1-hour standard The more stringent 8-hour standard was violated at nine of the 15 sites for the 2000-2002 period
Robust ozone formation requires a combination of intense sunlight (UV), hot temperatures and chemicals such as VOCs and NOx This combination occurred often in the summer of 2002
8-HOUR 1-HOUR START 8-HOUR 1-HOUR START
DATE SITE EXC EXC HOUR DATE SITE EXC EXC HOUR
May 24, 2002 Blue Hill 088 11 August 12, 2002 Stow 107 9
July 3, 2002 Boston(LongIs) 126 12 August 14, 2002 Adams 101 13
August 10, 2002 Blue Hill 086 16 August 18, 2002 Lynn 087 10
Exceedance Days and Total Exceedance Trends
Figures 1 and 2 show the recent trends in exceedance days and the total number of 1-hour and 8- hour exceedances
The analysis of the 1-hour data indicates a decreasing trend in both the number of exceedances and exceedance days over time In contrast, the 8-hour standard, which is more stringent, reveals an increase in exceedances and exceedance days compared to the 1-hour standard.
Figure 1 1-hr O 3 Exceedance Days and Total Exceedances 1987-2002 Ozone exceeded the 1-hour standard (0.125 ppm)
Figure 2 8-hr O 3 Exceedance Days and Total Exceedances 1987-2002 Ozone exceeded the 8-hour standard (0.085 ppm)
MADEP forecasts air quality daily, based on O3, from May through September Each day during that period, MADEP predicts the air quality as good, moderate, or unhealthy.
Air quality ratings are established by analyzing observations from the National Weather Service alongside predictive models This assessment incorporates data on meteorological conditions, ozone (O3), and nitrogen oxides sourced from both statewide and regional monitoring networks.
The table below describes the ratings used in the daily air quality forecasts.
Adverse Health Effects Ways to Protect Your Health
Good None expected No precautions necessary.
PAMS/Air Toxics Monitoring
A summary of the 2002 data during O3 season (April 1 – Sept 30) is listed below There were 15
O3 sites during 2002 in the state-operated monitoring network All of the sites except Worcester achieved the requirement of 75% or greater data capture for the year.
SITE ID C T CITY COUNTY ADDRESS OBS 1ST 2ND >.125 1ST 2ND 4TH >.08
0041 1 2 BOSTON SUFFOLK LONG IS.HOSPITAL 99 138 136 3 126 117
3003 1 2 MILTON NORFOLK BLUE HILL RESERV 99 150 133 2 134 116
1102 1 2 STOW MIDDLESEX US MILITARY RESERV 89 123 122 0 110 107
ABBREVIATIONS AND SYMBOLS USED IN TABLE
SITE ID = AIRS SITE IDENTIFICATION NUMBER POC = PARAMETER OCCURRENCE CODE (DIFFERENTIATES BETWEEN MONITORS AT A SITE) MT = MONITOR TYPE (1 =
The NAMS and SLAMS monitoring networks are utilized to assess air quality, with specific metrics indicating the percentage of valid days monitored during the O3 season The maximum 1-hour values for the first and second highest days are noted, with a focus on daily measurements exceeding 0.125 PPM, which corresponds to the 1-hour standard Additionally, the maximum 8-hour values for the first, second, and fourth highest days are recorded, targeting daily measurements that meet or exceed 0.085 PPM, aligned with the 8-hour standard.
The long term trends of 1-hour O3 exceedances for each site are shown below.
O 3 1-hour Exceedance Trends Number of O 3 exceedances of the standard (0.125 ppm)
ADAMS AGAWAM AMHERST WARE CHICOPEE
The long-term trends of 8-hour O3 exceedances for each site are shown below.
O 3 8-hour Exceedance Trends Number of O 3 exceedances of the standard (0.085 ppm)
ADAMS AGAWAM AMHERST WARE CHICOPEE
BOSTON(Long Is.) BOSTON(Harrison Ave) MILTON(Blue Hill)
In 2002, the state-operated monitoring network included eight SO2 sites, all of which met the data capture requirement of 75% or higher for the year Notably, the Lawrence site was closed in September 2002.
O M % MAX 24-HR MAX 3-HR MAX 1-HR ARITH
SITE ID C T CITY COUNTY ADDRESS OBS 1ST 2ND 1ST 2ND 1ST 2ND MEAN 25-025-
1004 1 1 FALL RIVER BRISTOL GLOBE STREET 84 027 027 107 080 126 114 0037 25-009-
0016 1 1 SPRINGFIELD HAMPDEN LIBERTY STREET 97 025 025 039 038 053 051 005425-015- 1 2 WARE HAMPSHIRE QUABBIN SUMMIT 97 020 018 021 021 022 022 0032
ABBREVIATIONS AND SYMBOLS USED IN TABLE
SITE ID = AIRS SITE IDENTIFICATION NUMBER POC = PARAMETER OCCURRENCE CODE (DIFFERENTIATES BETWEEN MONITORS AT A SITE) MT = MONITOR TYPE (1 =
The data capture percentages for NAMS, SLAMS, and other monitoring systems are detailed, with a maximum observation period of 24 hours, 3 hours, and 1 hour The first and second highest values for the specified time periods are recorded, while the annual arithmetic mean is calculated with a standard value of 0.03 PPM.
The long-term trends of annual arithmetic mean sulfur dioxide (SO2) levels at each monitoring site indicate a stable pattern in recent years, with an overall downward trajectory throughout the entire observation period Notably, Massachusetts consistently reports SO2 levels that are significantly below the established air quality standards.
Figure 5 SO2 Trends 1985 – 2002 Annual Arithmetic Means Standard = 0.03 ppm
BOSTON(Bremen St) BOSTON(Harrison Ave)
WORC(Central St) WARE SPRGFLD (Longhill) SPRGFLD (Liberty St)
There were 15 NO 2 sites during 2002 in the state-operated monitoring network All sites met the requirement of 75% data capture for the year A summary of the 2002 data is listed below.
SITE ID C T CITY COUNTY ADDRESS OBS 1ST 2ND MEAN
25-013-0003 1 8 AGAWAM HAMPDEN 152 SOUTH WESTFIELD STREET 95 044 043 0112 25-025-0002 1 3 BOSTON SUFFOLK KENMORE SQUARE 77 071 068 0253 25-025-0021 1 1 BOSTON SUFFOLK 340 BREMEN STREET, EAST
25-025-0041 1 8 BOSTON SUFFOLK LONG ISLAND HOSPITAL ROAD 91 069 066 0119 25-025-0042 1 1 BOSTON SUFFOLK HARRISON AVENUE 85 079 077 0241 25-013-0008 1 8 CHICOPEE HAMPDEN ANDERSON ROAD AIR FORCE
The data presents various locations across Massachusetts, highlighting specific properties and their respective attributes For instance, Fairhaven's Leroy Wood School has a rating of 91, while Lawrence's Essex High Street boasts a score of 81 Lynn's Parkland Avenue stands out with a rating of 93 Milton's Blue Hill Reservation is noted for its score of 95, and Newbury's Sunset Boulevard has an 88 Springfield's Liberty Street Parking Lot achieves a remarkable 96, whereas Truro's Fox Bottom Area in Cape Cod holds an 88 Ware's Quabbin Summit has a rating of 76, and Worcester's Central Street Fire Station is recorded at 94 These figures reflect the quality and significance of each location, contributing to a comprehensive overview of property assessments in the region.
TO CONVERT UNITS FROM PPM TO uG/M³ at standard conditions (25 celsius, 760 mmhg) MULTIPLY PPM x 1880
Standard: Annual Arithmetic Mean = 0.053 ppm
ABBREVIATIONS AND SYMBOLS USED IN TABLE
SITE ID = AIRS SITE IDENTIFICATION NUMBER POC = PARAMETER OCCURRENCE CODE (DIFFERENTIATES BETWEEN MONITORS AT A SITE) MT = MONITOR TYPE (1 =
NAMS, 2 = SLAMS, 3 = OTHER; 7 = PAMS/NAMS; 8 = PAMS/SLAMS) % OBS = DATA CAPTURE PERCENTAGE MAX 1-HR 1ST 2ND = FIRST AND SECOND HIGHEST VALUE FOR TIME PERIOD INDICATED ARITH MEAN = ANNUAL ARITHMETIC MEAN
The annual arithmetic means for each NO2 monitoring site indicate a stable trend in recent years, with a downward trajectory observed over the entire period Notably, Massachusetts' levels remain below the established standard.
Figure 6 NO2 Trends 1985-2002 Annual Arithmetic Means Standard = 0.05 ppm
CHELSEA BOSTON(Kenmore Sq) BOSTON(Long Island)
BOSTON(Bremen St) BOSTON(Harrison Ave)
LAWRENCE LYNN MILTON(Blue Hill) NEWBURY
EASTON FAIRHAVEN TRURO WORC(Central St)
In 2002, the state-operated monitoring network included nine CO sites, all of which met the requirement of capturing 75% or more of data for the year However, the Post Office Square site in Boston was closed in August 2002 A summary of the data collected throughout the year is provided below.
SITE ID C T CITY COUNTY ADDRESS OBS 1ST 2ND 35 1ST 2ND 9
0002 1 2 BOSTON SUFFOLK KENMORE SQ 590 COMM AVE 81 2.8 2.5 0 1.6 1.4 0 25-025-
0021 1 1 BOSTON SUFFOLK 340 BREMEN ST E BOSTON 87 3.5 2.7 0 2.0 1.8 0 25-025-
0038 1 1 BOSTON SUFFOLK FEDERAL POST OFFICE BLDG 94 3.9 3.7 0 3.1 2.2 0 25-025-
0007 1 2 LOWELL MIDDLESEX OLD CITY HALL, MERRIMACK
D HAMPDEN LIBERTY STREET PARKING LOT 93 4.6 4.5 0 4.2 3.3 0 25-013-
0020 1 2 WORCESTER WORCESTER CENTRAL STREET FIRE STATION 91 4.6 4.5 0 3.3 2.9 0 25-027-
0022 1 2 WORCESTER WORCESTER FRANKLIN/GRAFTON STREETS 88 3.3 3.2 0 2.6 2.1 0
Standards: 1-hour = 35 ppm 8-hour = 9 ppm
ABBREVIATIONS AND SYMBOLS USED IN TABLE 15
SITE ID = AIRS SITE IDENTIFICATION NUMBER POC = PARAMETER OCCURRENCE CODE (DIFFERENTIATES BETWEEN MONITORS AT A SITE) MT = MONITOR TYPE (1 =
NAMS, 2 = SLAMS, 3 = OTHER) % OBS = DATA CAPTURE PERCENTAGE MAX 1-HR 1ST 2ND = FIRST AND SECOND HIGHEST VALUE FOR TIME PERIOD INDICATED OBS > 35
The maximum number of one-hour averages exceeding 35 parts per million (PPM) is recorded, while the first and second highest values for the specified time period are noted Additionally, the count of eight-hour averages surpassing 9 PPM is tracked, adhering to the eight-hour standard.
In 2002, air quality data indicated that the 2nd-maximum value is crucial as it aligns with established standards Notably, Springfield recorded the highest 1-hour and 8-hour values; however, both measurements remained significantly below the regulatory limits.
2 nd Maximum 8-hour Values Standard = 9 ppm
BOSTON(Kenmore Sq) BOSTON(Sumner)
BOSTON(Bremen St) BOSTON(Post Office Sq)
LOWELL WORC(Central St) WORC(Franklin St)
SPRGFLD(Liberty St) SPRGFLD(E Columbus)
Particulate Matter 10-Microns (PM10) Summary
There were seven PM 10 sites Three sites had two samplers, which were operated simultaneously for precision purposes
In 2002, four out of eight sites successfully met the data capture requirement of 75% or higher for each calendar quarter, while sampler failures hindered Boston sites from reaching this benchmark A summary of the data from that year is provided below.
P 1st 2nd 3rd 4th Wtd.
O M % Highes t Highes t Highes t Highes t Arith. Site ID C T City County Address Obs Value Value Value Value Mean 25-013-
0027 1 1 BOSTON SUFFOLK ONE CITY SQUARE 23 59 59 49 39 31? 25-025-
0027 3 3 BOSTON SUFFOLK ONE CITY SQUARE 13 69 46 35 27 30? -25-027-
? INDICATES THAT THE MEAN DOES NOT SATISFY SUMMARY CRITERIA (NUMBER OF OBSERVATIONS FOR AT LEAST 1 QUARTER LESS THAN 75%)
Standards: 24-hour = 150 g/m 3 Annual Arithmetic Mean = 50 g/m 3
SITE ID = AIRS SITE IDENTIFICATION NUMBER POC = PARAMETER OCCURRENCE CODE (DIFFERENTIATES BETWEEN MONITORS AT A SITE) MT = MONITOR TYPE (1 =
NAMS and SLAMS represent different monitoring networks, with data capture percentages indicating the reliability of the observations The highest values are categorized as 1st, 2nd, 3rd, and 4th for the year, showcasing the top 24-hour measurements The weighted annual arithmetic mean (WTD ARITH MEAN) is calculated, with a standard threshold set at 50 µg/m³ An indicator of insufficient observations is denoted by the question mark.
TO CALCULATE MEAN THE DATA CAPTURE AT A SITE MUST EXCEED 75% FOR EACH QUARTER.
PM 10 long-term trends are shown for the annual arithmetic mean for each PM 10 site The data shows a yearly variability at most sites, with the overall trend being downward.
Figure 8 PM10 Trends 1989-2002 Annual Arithmetic Mean Standard = 50 ug/m3
BOSTON(City Sq) BOSTON(Columbus Ave)
BOSTON(Kenmore Sq) BOSTON(Southhampton St)
SPRGFLD(E Columbus Ave) SPRGFLD(Main St) SPRGFLD(How ard St) WORC(Washington St) WARE
Particulate Matter 2.5-Microns (PM2.5) Summary
The PM2.5 monitoring network was established in late 1998, with monitoring activities commencing in January 1999 By 2002, the state-operated network included 21 PM2.5 monitoring sites, seven of which featured collocated monitors.
Throughout 2002, the PM 2.5 program has seen significant improvements, including software upgrades and mechanical enhancements to samplers that boost instrument performance Additionally, the implementation of new filter distribution methods and lab automation has increased field efficiency, allowing staff to respond more effectively to mechanical issues.
Machine malfunctions remain a significant concern for MADEP, as prolonged equipment downtime leads to sample loss In response, MADEP has taken the unusual and costly step of assigning a dedicated staff member for the constant calibration and repair of PM2.5 monitors, which has contributed to improved data capture However, ongoing reductions in staffing levels are jeopardizing MADEP's ability to maintain this singular focus on equipment maintenance.
In 2002, the overall network-wide data capture reached 78.8%, marking a 15% increase from the previous year and achieving the highest yearly average to date Despite this progress, individual sites continue to show significant disparities in data capture rates Furthermore, seasonal fluctuations are impacting the consistency of results, making it challenging to maintain data capture levels above 75%.