The purpose of this document is to identify those water quality contaminants that the Department of Environmental Services (DES) recommends be tested in private wells. These contaminants are generally related to New Hampshire's geology and types of land use.

State, Town, and Lender Requirements

There is no state requirement for testing the water quality of private wells; accordingly, the following information is offered only for educational purposes. State law (RSA 477:4-c), however, requires that certain information concerning a home’s water system be disclosed to a purchaser, including an unsatisfactory water test. The term "unsatisfactory water test" is not defined in statute.

Since there are no state water quality testing requirements, a few towns, primarily in southern New Hampshire, have identified lists of required water quality test parameters. Such town requirements are typically expressed as the obligation to test for certain contaminants, but not necessarily to achieve compliance. This testing is typically associated with the building code requirements for new construction, such as a certificate of occupancy. Please check with your town to see if water quality testing of a private well is required and under what circumstances. The Veterans Administration (VA), Federal Housing Administration (FHA) and many banks require some water quality testing when writing a mortgage. However, their requirements are not consistent, and historically there has been more emphasis on factors that pertain to aesthetics than factors that pertain to health.

LIST OF SUGGESTED CONTAMINANTS
The list of contaminants below has been prepared after a review of the extensive records of DES's public water supply program. Although more test parameters could be added, this list provides a reasonable balance between the high cost of extensive testing and the relatively low cost of testing for only those contaminants that are more commonly found in New Hampshire.

If contaminant(s) are found, please reference the DES fact sheet(s) for that particular contaminant at www.des.nh.gov/wseb then link to "fact sheets" under "Publications" and see fact sheet WD-WSEB-2-5, entitled "Considerations When Purchasing Water Treatment Equipment."
 

ADDITIONAL TESTING BASED ON THE ANALYSIS OF THE WELL'S LOCATION OR THE RESULTS OF THE FIRST ROUND OF WATER QUALITY TESTING

Organics Testing

There are two groups of organic contaminants, volatile organic compounds (VOC) and synthetics organic compounds (SOC). Only VOCs are generally recommended for testing. All contaminants in the organics group come from manmade sources. Laboratory testing for these contaminants is expensive. There are approximately 60 organic contaminants in these two categories.

Volatile Organic Compounds (VOC). The DES recommended test for volatile organic chemicals (VOC) targets gasoline compounds, including MtBE, and industrial solvents. Repeat testing frequency for organics depends on a site review of the area near and uphill of your well identifying past or present land uses that make such contamination possible. Examples of some, but not necessarily all, activities that would produce these contaminants include heavy industrial or commercial activity, past or present landfills, buried chemical or hydrocarbon storage tanks. Some other water quality factors important in judging whether VOC organics testing may be necessary include:

Synthetic Organic Contaminants (SOC). Testing for the remaining organics, often characterized as pesticides and herbicides, is very expensive, costing from $250 –$500 per sample. Although DES does perform such water quality testing, these tests are available only to public water systems. Some other water quality factors important in judging whether pesticides/herbicide organics testing may be necessary include:

Gross (Beta) Screen Testing
Radionuclides, producing high beta levels, are believed to occur infrequently in New Hampshire’s geology. Consider testing for beta if the screen alpha mineral radionuclides are elevated. The DES laboratory does not process beta samples. Laboratory options for beta testing include the Health and Environmental Testing Laboratory of the State of Maine. They can be reached at (207)-287-2727. A list of private labs along with phone numbers follows this fact sheet. Please contact these labs for additional information on tests performed and costs. Other nationally certified laboratories for processing beta testing can be found at www.des.nh.gov/wseb

FREQUENCY OF TESTING
Water quality in wells is normally stable and, if varying, the change occurs slowly. Thus the interval between water quality samples taken from a properly constructed well, located in a safe area, can generally be in terms of years. On the right hand side of the chart on page 2, we

offer our recommendations concerning how frequently to test water quality. In developing this frequency we have considered similar requirements for public water systems and given significant emphasis to the cost of laboratory work. These frequencies are appropriate for wells in rural areas believed to be free of groundwater contamination sites.

There are a variety of conditions that would prompt modifications of these average monitoring frequencies. Some include:

Areas of Higher Contaminant Possibility. In more built-up areas and those with known groundwater contamination sites, increasing the sampling frequency for appropriate contaminants is warranted. In these situations the frequency for each contaminant would be determined individually based on an assessment of the well type, contaminant type, and level of health risk.

Proper Well Construction. DES recommends that wells not be sampled for bacteria unless their construction is excellent. Poor well construction can lead to high bacterial counts. Proper well construction is detailed in fact sheets WD-WSEB-1-2 through 1-6. DES recommends taking a bacterial test after any well repair, and after every pump or plumbing modification, but only after substantial flushing to clean the area where work occurred.

Sample Timing and Location. Where treatment is already installed, DES recommends that the sample be taken of the treated water just before the treatment system is scheduled to be regenerated. Where you desire to have a record of the baseline quality of your well water, additional testing should be done of the untreated water. Such testing provides a historical and official record of your well’s quality. This historical data is often valuable when contending that contamination of your well has occurred by the recent activities of others.

Higher Concentrations. Where any health parameter is greater than 75 percent of the public drinking water maximum contaminant level (MCL), more frequent sampling should be performed until one can reasonably conclude that the concentration of that contaminant is reliably and consistently below the MCL. Suggested accelerated sampling frequencies are shown in the extreme right hand column of page 2 for contaminant situations that have stabilized. This column is identified with the heading "greater than 75 percent." Where the contaminant level in your well is unstable or unknown, much more frequent testing is warranted. This testing frequency would be individually determined based on the specifics of the area and the contaminant risk.

Variation in Quality. Where the water quality in a supply varies after a heavy rain or when you have experienced a rapid and unexplained substantial change in quality from the past long term performance of that well, we suggest weekly or monthly sampling for bacteria, and possibly other parameters, until the condition stabilizes. Heavy precipitation tends to mobilize bacteria and thus highlight conditions of poor well construction or inadequate soil filtration. Thus bacterial sample(s) should always be taken after a heavy rainstorm.

Testing Laboratories
Either an independent laboratory or the DES Laboratory can process laboratory testing of private well samples. Independent laboratories testing private wells are not required to be accredited in New Hampshire. A list of those laboratories that are accredited is given at www.des.nh.gov/asp/NHLAP/labsview.asp. A summary list of accredited independent laboratories is also attached to this fact sheet. DES does not maintain a list of non-accredited laboratories.

If you desire to use the DES laboratory, sample bottles can be ordered through www.des.state.nh.us/lab/ and select "Homeowner; Test Containers".

For More Information

For an overall listing of water supply related fact sheets, please request DES fact sheet WD-WSEB-15-2. For more information concerning water quality testing of private wells, please call the DES's Water Supply Engineering Bureau at 271-3139. For costs associated with water quality testing, you can call the DES Lab at 271-3445 or call a certified laboratory.

We would appreciate your comments concerning this fact sheet. Drinking water fact sheets are available through the DES web site at: www.des.nh.us.gov/wseb then select: fact sheets. Please check the Internet annually for updates to this document. 12/03