|
WATER GREMLIN PUBLIC HEALTH ASSESSMENT:. PUBLIC COMMENT. DRAFT
<br />Small areas of stained flooring. were observed.in the manufacturing building near the: coating
<br />operations and in thevicinity of drums of unused TCE,.
<br />• "..:€t is possible the leaks may have occurred in. buried piping (of the.above ground storage tank for
<br />fuel oll) .or the base, which could have impacted soil and groundwater."
<br />• "...The full.exte.ntof lead. soiI contamination was not .yet been determined. Th e. exa ct. sou rce of`the
<br />contamination also has not been identified:'
<br />Also in 1995, Braun.collected an additional 48 soil samples to the south.and southeast of the Water
<br />Gremlin building as part of:a Phase. I Environmental Site Assessment to determine the extent of lead
<br />contaminated lolls, Of. the 48 samples, seven contained lead concentrations above the clean-up criteria
<br />of 400 ppm.and those locations were identified for follow-up soil removal (Braun, 1996). By the fall of
<br />1996, over 1,000 cubic yards of.contaminated soil was excavated and disposed of in a landfill. Eight cubic
<br />yards of contaminated so€1 remained on. site because it was located around Sulbsurface infrastructure
<br />and was covered during the next facility building expansion (MPCA, 1997). €n June 1997; MPCA
<br />determined that no further. action was needed to. address the: identified release of lead in the.soll.
<br />in 1997, sail,.surface.Water, and groundwater were sampled forVOCs.near the :Water Gremlin facility
<br />(Wenck, 2019a.)..Low levels of TCE were detected. in some soil samples; but no VOC.s w.ere:found in the
<br />surface water. Chlorinated solvents were found in the shallow groundwater (Wenck, 2019a).
<br />Groundwater monitoring wells were installed in. six locations in the shallow aquifer around the property
<br />between 1.997 and.1999: (Wenck,.2019a).. Solvent breakdown products and nonchlorinated and
<br />petroleum -based compounds were also found in the groundwater (Braun, 1998). Many of the
<br />contaminants in the shallow aquifer were above the.MDH HRU for drinking water. No VOC:s were
<br />detected in an additional monitoring.w.e.11 placed in the deeper buried glacial aquifer (Wenck, 2019a).
<br />5ampies were collected to evaluate the potential for contamination to affect groundwater used for
<br />drinking water. The White.Bea rTowns hip Municipal Well #5,.which is greater than 400 feet deep in the
<br />Prairie du Chien and. lordan bedrock aquifers, was. sampled for VOCs in 1998 and:none were .detected
<br />(Braun, 1998.). A groundwater receptor survey was conducted and it was determined that all drinking
<br />water wells draw f om.either the buried glacial .aquifer or the bed rock. aqulife r, neither of which were
<br />found to be contaminated (Braun, 1598). Groundwater flow was shown to be flowing to thesouth at
<br />that time (Braun, 2004).
<br />Groundwatersampling was conducted until.2004 and concentrationsof groundwater contaminants
<br />declined over time. The data also suggested that contaminabon was limited to the shallow aquifer by a
<br />confining layer located below it. In 2004,..MPCA issued a No Further Action letter for the. identified
<br />release. to the groundwater because contaminants were below the HRLs, on thecondition that if
<br />.property use changed, theuse will need to be. reevaluated (MPCA, 2004). The No Further Action letter
<br />lists 20 compounds identified as released to the. groundwater:.acetone; benzene, ch lo roet h a n e,
<br />chloroform, 1,1-d€chloroethane, 1,2=d1chloroethane) 1,1-dichloroethylene, cis-1.2-dichloroethylene,
<br />trans-1,1-di6loroethylene, dichlorodifluorormethane; ethylbenzene,.methyl ethyl.ketone, methyl..
<br />isobutyl ketone, tetrahydrofuran, toluene, 1,1,1=trich loroethane, trichloroethylene,.
<br />trichlorofluoromethan% vinyl chloride and xylenes.
<br />Oil
<br />
|