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Use of DNA Markers for Investigating Sources of Bacteria in Contaminated Ground Water: Wooster Township, Wayne County, Ohio

In June 2  6, the U.S. Geological Survey (USGS), in cooperation with   the Ohio Environmental Protection Agency (Ohio EPA), collected and   analyzed samples from some of the affected wells to help investigate   the possibility of human-origin bacterial contamination. Water   samples from 12 wells and 5 home sewage-treatment systems (HSTS)   were collected. Bromide concentrations were determined in samples   from the 12 wells. Samples from 5 of the 12 wells were analyzed for   wastewater compounds. Total coliform, enterococci and Escherichia   coli (E. coli) bacteria concentrations were determined for samples   from 8 of the 12 wells. In addition, two microbial source-tracking   tools that employ DNA markers were used on samples from several   wells and a composite sample of water from five septic tanks. The   DNA markers from the Enterococcus faecium species and the order   Bacteroidales are associated with specific sources, either human or   ruminant sources.  Bromide concentrations ranged from  . 4 to  .18 milligrams per liter   (mg/L). No wastewater compounds were detected at concentrations   above the reporting limits. Samples from the 12 wells also were   collected by Ohio EPA and analyzed for chloride and nitrate.   Chloride concentrations ranged from 12.6 to 61.6 mg/L and nitrate   concentrations ranged from 2.34 to 11.9 mg/L (as N).  Total coliforms and enterococci were detected in samples from 8   wells, at concentrations from 2 to 2   colony-forming units per 1     milliliters (CFU/1   mL) and  .5 to 17 CFU/1   mL, respectively. E.   coli were detected in samples from three of the eight wells, at   concentrations of 1 or 2 CFU/1   mL. Tests for the human-specific   marker of enterococci, the esp gene, were negative in the seven   samples tested, including the composite sample of HSTS water. DNA   with the general Bacteroidales marker was detected in samples from   four wells, but the tests for both the human- and ruminant-  associated markers were negative. The presence of the PCR   (polymerase chain reaction) -detectable DNA for the general fecal   Bacteroidales marker is indicative of fecal contamination and   recently recharged water.      (microbial source tracking); (MST); (bacterial source tracking);   (BST); (E. coli); (Bacteroidales); (bromide); (Enterococcus);   (chloride)

In progress
Start Date
End Date
Scope of Study
Field Investigation
Laboratory Investigation
State Province
Resource Being Monitored
Emission / Release / Discharge / Waste Management
Human Health
Beneficial Use Impairment Assessments
Restrictions on Drinking Water Consumption or Taste and Odour Problems
Annex Numbers
Pollution from Contaminated Groundwater
Pollution from Non-Point Sources
Remedial Action Plans and Lakewide Management Plans
  • Annex Numbers
    Annex Numbers
    Pollution from Contaminated Groundwater
    Pollution from Non-Point Sources
    Remedial Action Plans and Lakewide Management Plans
  • Annex 17

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