TRI/TUR TRENDS
Total Hazardous Air pollutants are reported by large (typically Major) Point sources only as part of annual air source registrations to the state, however this data is not available online or readily to the public. The data presented below is from the TRI database from EPA which includes the HAPs as well as other target compounds as a best indicator of trends in chemical emission other than Criteria pollutants. This data is only available from self-reported facilities that exceed the reporting thresholds of 10 or 25 tons used per year for TRI and MA TURA reports, and/or who have a MADEP Air permit that requires annual or triennial Source Registration reporting.
Note: Beverly sources contribute very little TRI Air emissions, which is why it can barely be seen in the chart. This data was taken from the EPA TRI Explorer database. It is based on reported figures and does not try to provide a stable baseline based on either chemicals required to be reported, or facilities reporting. The EPA has made changes to both the chemicals required to be reported, as well as who must report throughout this period.
While tracked emissions had been declining steadily, a change in reporting requirements in 1998 added electric utilities to the EPA TRI reporting requirements. This change required the Salem Power Station to begin reporting, where the plant had previously been exempt. Salem Power Station is responsible for the elevation in TRI Air emissions seen beginning in 1998. Had the plant been reporting previously, it is assumed that the total numbers for Essex County would have been much higher in previous years, thus air emissions in Essex County are likely less now, even when including the power plant emissions, than in the past when the plant was unaccounted for in this report. However, the trend for the three target communities in this report is not possible to determine due to the absence of this significant source in the reporting prior to 1998.
Part of the reason for the reduction in air emissions in recent years appears to be a loss of businesses in the three target communities as well as in Essex County as a whole. When reporting started in 1988, the total number of reporting facilities in Essex County was 85, versus 69 reporting companies in 2003. This trend also appeared at the target community level, where 11 companies in the three target communities reported in 1988 (8 in Salem, 3 in Beverly), versus 6 companies in 2003 (4 in Salem, 2 in Beverly). The companies that remain have also made successful strides towards reducing the emission of these reported pollutants.
In addition, we looked at how air emissions have compared with total chemical releases on and off-site (including releases of wastewater, releases to the ground or water, or shipped off-site). The percentage of total releases versus air emissions has stayed fairly constant at an average of 86% from 1988 through 2003 (ranging between 75% and 95%). Thus total releases have tracked similarly to the total air emissions shown in the chart.
Since this percentage of air emission to total releases is relatively constant in the EPA TRI data, it is safe to assume that this would also follow in the MA TUR data. Thus to get a fuller picture of the actual trends in the years prior to the Salem Power Plant reporting in the EPA TRI data, the overall releases trend can be reviewed in the MA TUR data which includes them since 1991. While the table below does include all releases (air, wastewater, to ground, shipped off-site, etc.), the trend is expected to be similar for the portion of total releases that are air emissions for the three target communities.
Note: Data at the County level is not readily accessible for the public and thus this chart does not have the County trend line as did the EPA TRI trend chart provided previously in this report.
With the exception of a very high spike of reported releases in 2000, generally the total releases from the facilities reporting to the MA TUR program from the three target communities has been on a steady decline overall since 1991. (Note-the spike in 2000 was from reported release of hydrochloric acid from the Salem Harbor Power plant- 1.9 million pounds in 2000, versus 0.5 million or less in previous and subsequent years)
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