Keiser calls landfill reports 'good news'
Last week the Town Council received two reports on landfill monitoring tests conducted in September and December from consultants GeoEnvironmental (GZA) of Providence and Norwood, Mass.
In the reports, GZA summarized that "no findings were above limits" and that all results "were compliant with requirements." The reports also referred to "no exceedances" of maximum allowed scores, noting that "no standards (exist) for some detected metals." Town Administrator Bruce Keiser said those findings represented "good news" and shows the landfill "continues to demonstrate it is a safe site."
Keiser said the September report was delayed by GZA because its staff needed to give added attention to another client last fall.
The latest report revealed that Lot 47, abutting the landfill, has been added for testing, to determine its impact on the landfill and to help evaluate it as an alternate site for the highway barn. The report noted that nitrates and coliforms were not detected in December in the Lot 47 well, but small amounts of barium, cobalt, nickel and zinc were recorded. Keiser said September tests detected small amounts of nitrates and coliform in the Lot 47 well.
Methane, a product of decaying matter and a possible explosive, was detected at all 14 screened locations in December, none in excess of state regulations or considered dangerous. GZA attributed those results to possible test equipment malfunction and will rescreen all locations in March, according to the report.
The reports say that "contamination concentrations remained relatively constant during six years of quality monitoring," GZA completed for the town. GZA found two increasing trends and six decreasing trends in the test results.
The report listed 'two statistically significant increasing trends" of barium and cobalt. GZA suggested that the cobalt, found for the third time this year, "could be migrating into the landfill from up gradient off site sources," or "from the soil near the well."
Last spring when GZA reported high cobalt test results for a private well across from the landfill, a wave of worry beset officials and some residents until an investigation showed that the test result was due to a technician error and a follow up test was negative. GZA noted cobalt is found naturally in soil. The consultant switched testing laboratories about the time the technician error was reported.
GZA listed decreasing repeat findings during the latest monitoring for two volatile compounds: dichloroethene, with a finding of two parts when none is allowed, and chlorobenzene, tested for five parts, where 100 parts are allowed. Both scores were cited as lower than previous test results.
The consultant also listed findings in below exceedance amounts again for eight metals in eight landfill wells and one offsite well tested. The metals are: arsenic, chromium, copper, lead, nickel and zinc as well as the barium and cobalt. Arsenic, first detected in 2001 and 2002, showed up for the first time in at least a year, according to the report. GZA suggested much variation in metals might be related to seasonal fluctuations in groundwater levels.
Notably, Middletown leaders asked councilors to support a resolution to lower standards for arsenic in soil by raising the limit from seven parts to 15 parts. Middletown is seeking state legislation for the change. If approved, it would mean less mitigation of arsenic than is currently required.
Councilors here acknowledged the correspondence but did not discuss or act on the request.
Limits for lead were lowered as a result of the switch from GZA's own laboratory to a state lab. The lead in the sampled well was below the new detection limit, the report noted.