2007

The source of the Nesenkeag Hill water supply is two wells and a pump station located between Jewell Court and Raintree Drive in Londonderry, NH.  Well # 1 is located 960 feet northwest of the pump house.  Well # 2 is located 280 feet northwest of the pump house.  Treatment consist of chlorine addition to kill bacteria, softening to reduce hardness and remove iron and manganese, phosphate addition to sequester iron and manganese and aid in corrosion control, and pH adjustment using potassium carbonate to aid in corrosion control.
NESENKEAG
EPA # 1392240
Inorganic Contaminants	Units	MCLG	MCL	Level Detected	Range	Year	Violation Yes/No	Typical Source of Contaminant
Fluoride	ppm	4	4	0.58	n/a	2005	NO	Erosion of natural deposits
Volatile Organic Contaminants	Units	MCLG	MCL	Level  Detected	Range	Year	Violation Yes/No	Typical Source of Contaminant
Total Trihalomethanes (TTHMs)	ppb	n /a	80	1.1	1.1	2006	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	0.31	0.0 - 0.7	2006	NO	Water additive used to control microbes
Radiological Contaminants	Units	MCLG	MCL	Level Detected	Range	Year	Violation Yes/No	Typical Source of Contaminant
Gross Alpha (Compliance)	pCi/L	0	15	2.6	2.6	2006	NO	Erosion of natural deposits
Combined Radium	pCi/L	0	5	0.6	0.3 - 0.6	2006	NO	Erosion of natural deposits
Uranium	ppb	0	30	6.5	5.4 - 6.5	2006	NO	Erosion of natural deposits
Radon	pCi/L	Not Regulated		3,240	3,240	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.
Inorganic Contaminants	Units	MCLG	AL	90th percentile sample value	# sites above AL	Year	Violation Yes/No	Typical Source of Contaminant
Copper	ppm	1.3	1.3	0.167	0 of 5	2006	NO	Corrosion of household plumbing system
Source Assessment Information
		Summary of Susceptibility Factors
Source Name	Date	Low	Med	High
Bedrock Well # 1	2/28/06	10	1	1
Bedrock Well # 2	2/28/06	10	1	1
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