2007

Thurston Woods obtains its water from two bedrock wells.  Bedrock Well # 1 is located 50 feet north of the pump house and is 760 feet deep and yields 10 gallons per minute.  Bedrock Well # 2 is located 60 feet north of the pump house and is 447 feet deep and yields 20 gallons per minute.  Current water treatment consists of chlorine for disinfection, aeration to remove radon, and an arsenic removal system.  
THURSTON WOODS
EPA #  1332050
Inorganic Contaminants Units MCLG MCL Level Detected Range Year Violation Yes/No Typical Source of Contaminant
Nitrate as Nitrogen ppm 10 10 0.35 n/a 2006 NO Runoff from fertilizer use; leaching from septic tanks, sewage; erosion of natural deposits.
Radiological Contaminants Units MCLG MCL Level Detected Range Year Violation Yes/No Typical Source of Contaminant
Combined Radium pCi/L 0 5 2.1 nd - 2.1 2006 NO Erosion of natural deposits
Radon pCi/L Not Regulated 567 nd - 567 2006 n/a Erosion of natural deposits
Radon is a radioactive gas that you can't see, taste or smell.  It can move up through the ground and into a home through cracks and holes in the foundation.  Radon can also get into indoor air when released from tap water from showering, washing dishes, and other household activities.  It is a known human carcinogen.  Breathing radon can lead to lung cancer.  Drinking water containing radon may cause an increased risk of stomach cancer.  Presently EPA is reviewing a standard for radon in water.
Volatile Organic Contaminants Units MCLG MCL Level  Detected Range Year Violation Yes/No Typical Source of Contaminant
Total Trihalomethanes (TTHMs) ppb n /a 80 1.8 1.1 to 1.8 2005 NO By-product of drinking water chlorination.
Haloacetic Acids (HAA5) ppb n/a 60 1.8 n/a 2005 NO By-product of drinking water chlorination.
Volatile Organic Contaminants Units MRDLG MRDL Average Level  Detected Range Year Violation Yes/No Typical Source of Contaminant
Chlorine ppm 4 4 0.46 0.28 to 0.7 2006 NO Water additive used to control microbes
Source Assessment Information
  Summary of Susceptibility Factors
Source Name Date Low Med High
Bedrock Well # 1 2/28/06 9 3 0
Bedrock Well # 2 2/28/06 9 3 0
The complete Assessment Report is available for inspection.  For more information call Gary Tetley or visit NH DES's Drinking Water Source Assessment Program web site at www.des.state.nh.us/dwspp