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How to Read Results Table

Parameter

Number of locations sampled

  • Sometimes it is not possible to collect an initial (first) water sample and a flushed (second) water sample at each building. This column shows, for a single sampling event, the number of locations where initial or flushed samples were collected.

Range in initial samples

  • Range will show the lowest and highest amount found in initial samples for the parameter.

Range in flushed samples

  • Range will show the lowest and highest amount found in flushed samples for the parameter.

Number of locations with resampling

  • The number of locations that have been resampled due to one or more water quality parameter needing further evaluation.
  • * (or numeric superscript) explains why a building was resampled for a certain parameter.

USA EPA Drinking Water Values

  • These are based on drinking water standards established by federal or state agencies. Drinking water values have been set to protect human health using the best available scientific research. After each number, a letter is provided to show which agency established (created) that value. At the end of the tables under "Value Description" you will find the letters, screening level name, and a description.

Health-based Level

  • Health-based screening values have been set using the best available scientific research. After each number, a letter is provided to show which agency established (created) that value.

Units of Measurement

  • mg/L = milligrams per liter
  • µg/L = micrograms per liter
  • µmhos/cm = microhos per centimeter
  • NTU = Nephelometric Turbidity Units
  • SU= Standard Unit

Value Descriptions

  • Action Level (AL): The Level of a contaminant that requires action when too high. The concentration of lead or copper, if exceeded in over 10% of homes tested, triggers treatment and other actions.
  • Agency for Toxic Substances and Disease (ATSDR) Reference Dose Media Evaluation Guide (RMEG): The highest amount of a chemical a child can be exposed to in drinking water for more than one year and no harm would be expected. Learn more at www.atsdr.cdc.gov/hac/phamanual/appf.html.
  • ATSDR Registry Environmental Media Evaluation Guide (EMEG): The highest amount of a chemical a child can be exposed to in drinking water for more than one year and no harm would be expected (health effects other than cancer). Learn more at www.atsdr.cdc.gov/hac/phamanual/appf.html.
  • Department of Environment, Great Lakes, and Energy (EGLE) 201 Cleanup Criteria: The cleanup criteria are the risk-based screening levels developed by EGLE (formerly Michigan Department of Environmental Quality) for corrective actions. When the Part 201 Criterion for a chemical is an aesthetic level below a health-based value, the health-based value is also provided as a footnote in the document.
  • U.S. EPA Health Advisory (HA): The level of a contaminant in drinking water below which no harm is expected during short-term or a lifetime of exposure.
  • U.S. EPA Maximum Contaminant Level (MCL): The level of a contaminant not allowed to go over (exceed) in drinking water. This level is set as close to the MCLG (defined below) as feasible and taking cost into consideration.
  • U.S. EPA Maximum Contaminant Level Goal (MCLG): The level of a contaminant in water at which no known or expected health problems would occur.
  • U.S. EPA Maximum Residual Disinfectant Level (MRDL): The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants.
  • U.S. EPA Regional Screening Level (RSL): The amount of a chemical in drinking water that is not expected to harm a child's health (health effects other than cancer). This is considered protective for adults too. Learn more at www.epa.gov/risk/regional-screening-levels-rsls.
  • U.S. EPA Secondary Maximum Contaminant Level (sMCL): The level of a contaminant that is recommended but not required to follow. Usually, this value is about the look, taste, and smell of water. 
 

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