Posted on March 21, 2019
AUSABLE TWP. – A report commissioned by the Michigan Department of Environmental Quality (MDEQ) states that a section of the AuSable River mouth slated to be dredged by the Army Corps of Engineers (USACE) “is not impacted” by polyfluoroalkyl substances (PFAS).
However, the report shows low levels of PFAS in surface water near the dredging area and in course sediments to be dredged from the site.
The report is the result of AuSable Township officials, who requested a soil report ahead of the dredging, which is going to take place this spring.
USACE periodically dredges the river mouth because natural river action deposits sand and silt filling the channel and nearby marinas.
The findings were presented to the AuSable Township Board of Trustees earlier this month during a regular meeting. There was no discussion about the results; however, each board member received documents including a technical memorandum, figures, tables, sediment and photo logs.
The initial sampling took place in October, but Superintendent Leisa Sutton didn’t receive the results until the March meeting.
AECOM – one of several agencies that took soil samples – conducted the work on two non-consecutive days, which were Oct. 4 and 9, due to adverse weather conditions.
MDEQ and AECOM, along with Affiliated Researchers, LLC, Vista Analytical Laboratory and TestAmerica Laboratories, Inc worked together to complete the sampling physical sampling.
Affiliated Researchers, LLC collected sediment cores from the proposed dredging area and Vista conducted the PFAS analysis. MDEQ used an isotope dilution method for analysis of 24 PFAS compounds and the total organic carbon (TOC). Sediment grain size distribution analyses were performed by TestAmerica.
There were a total of 12 sediment samples collected from six cores. The results revealed that all 12 samples were below the detection limit for all 24 PFAS compounds.
Although the dredging area was not impacted by PFAS, as stated in the report, the conclusions stated that low level detections of PFAS are still present in the AuSable River and Lake Huron.
The results stated further that results of surface water samples collected from the AuSable River in August 2018, near the proposed dredging area showed low levels of PFAS.
Residents interested in observing the results in more detail are encouraged to visit AuSable Township to receive a copy from Sutton.
The AuSable Township Hall is located 4420 N. US 23, AuSable. Questions can be directed to the township by calling 739-9169.
Source: iosconews.com
