2007

Our watershed is a 27.5 square mile area from which rainfall drains, becoming a source for the Pennichuck Brook, and ultimately, the Pond System.  This is Pennichuck's primary source of water, accounting for about 75% of our total annual supply.  Other supplementary sources of water are the Bon Terrain Well, in Amherst, NH, and the Merrimack River, which is used primarily during the summer months.  The well located off Thorntons Ferry Road in Amherst, NH was not used during 2006.  Treatment consists of flocculation, sedimentation, filtration, chlorination for disinfection, pH adjustment, and phosphate addition to control corrosion.
Nashua
EPA # 1621010
Microbiological Contaminants	Units	MCLG	MCL	Highest % positive in a month		Month	Violation Yes/No	Typical Source of Contaminant
Total Coliform Bacteria	Positve/Negative	Negative	≥ 5% positive per month	2		Jul-06	NO	Naturally present in the environment
E. coli Bacteria	Positve/Negative	Negative		0			NO	Naturally present in the environment
Health Effects
Coliforms are bacteria which are naturally present in the environment and are used as an indicator that other, potentially-harmful,
bacteria may be present.  Coliforms were found in more samples than allowed and this was a warning of potential problems.
Inorganic Contaminants	Units	MCLG	MCL	Level Detected		Sample Date	Violation Yes/No	Typical Source of Contaminant
Turbidity	NTU	0	TT=1	0.28		10/27/06	NO	Soil Runoff
			TT=% of samples < 0.3	100%		2006	NO
Inorganic Contaminants	Units	MCLG	MCL	Level Detected	Range	Year	Violation Yes/No	Typical Source of Contaminant
Barium	ppm	2	2	0.014	n/a	2006	NO	Discharge from drilling wastes; discharge from metal refineries; erosion of natural deposits
Volatile Organic Contaminants	Units	MCLG	MCL	Running Annual Average	Range	Year	Violation Yes/No	Typical Source of Contaminant
Total Trihalomethanes (TTHMs)	ppb	0	80	22.4	2.8 to 50	2006	NO	By-product of drinking water chlorination
Haloacetic Acids	ppb	0	60	16.2	0.1 to 37	2006	NO	By-product of drinking water chlorination
Total Organic Carbon	ppm	n/a	TT	0.9	nd to 2.3	2006	NO	Naturally present in the environment
Volatile Organic Contaminants	Units	MRDLG	MRDL	Distribution System Monthly Average	Range	Year	Violation Yes/No	Typical Source of Contaminant
Chlorine	ppm	4	4	0.64	0.45 to 0.84	2006	NO	Water additive used to control microbes
Inorganic Contaminants	Units	MCLG	AL	90th percentile sample value	# sites above AL	Year	Violation Yes/No	Typical Source of Contaminant
Lead	ppb	0	15	8	2	2005	NO	Corrosion of household plumbing system
Copper	ppm	1.3	1.3	0.13	0	2005	NO	Corrosion of household plumbing system
Source Assessment Information					The complete Assessment Report is available for inspection at Pennichuck Water Works Treatment Plant.  For more information, call Gary Tetley at 913-2378 or DES at 271-3303, or visit NH DES's Drinking Water Source Assessment Program web site at www.des.state.nh.us/dwspp/dwsap.htm.
		Summary of Susceptibility Factors
Source Name	Date	Low	Med	High
Harris Pond/Penn. Brk.	5/15/02	6	3	2
Supply Pond	5/15/02	6	3	2
Merrimack River	5/15/02	2	4	5
Bon Terrain Well	1/31/01	8	1	3