Before the well is installed
Establish a site for the well that will protect it from contamination:
- Where possible, the well should be located uphill and a maximum possible distance from any potential sources of contaminants, such as pesticide or fertilizer storage areas, road salt storage, gasoline, and fuel oil tanks.
- Surface water should drain away from the area of the well.
- If possible, maintain the following minimum separation distances:
- 10 ft to any building
- 15 ft to property lines
- 50 ft to septic tank
- 100 ft to sewage system
- 50 ft to stream, lake, or wetland
Use a well driller who is registered with the New York State Department of Environmental Conservation (DEC). A list of registered drillers can be obtained from the Tompkins County Health Department (TCHD).
Determine if there are any unused wells existing on the property. These wells should be properly abandoned to protect your ground water source from contamination. Please contact the TCHD for information on proper well abandonment procedures.
For more information on water well consumer protection click here.
After installation
Please have your well driller provide a copy of the well completion report (sometimes called the well log) to Environmental Health at tceh@tompkins-co.org and DEC at NYSWaterWells@dec.ny.gov. Hard copies can be mailed to: TCHD, 55 Brown Rd, Ithaca, NY 14850 and NYSDEC Water Well Program, 625 Broadway, 4th Floor, Albany, NY 12233.
A properly installed well should have the following items:
- The well casing should extend at least one foot above the ground surface (at least two feet above the 100 year flood elevation).
- The ground surface immediately around the well should be graded to direct surface water away from the well.
- The new well should be shock disinfected. This procedure is often performed by the well driller at the time of installation. The TCHD can also provide directions on how to shock disinfect the well.
- Make sure the well is protected with a tight fitting, vermin-proof well cap or sanitary seal that is properly vented. The vent should face downward, be screened, and be at least 1 foot above the ground surface.
- The water should be tested to establish safety of the new water source. This should be done after shock disinfection, when there is no longer any chlorine present in the water. Please refer to Table 1 for tests recommended by the TCHD.
Table 1: Individual Residential Well Water Supply Quality Testing
| Test | Maximum Contaminant Level (MCL) |
| Coliform bacteria | Any positive result is unsatisfactory |
| Chloride | 250.0 |
| Lead | 0.015 mg/L |
| Nitrates | 10 mg/L as Nitrogen |
| Nitrites | 1 mg/L as Nitrogen |
| Iron | 0.3 mg/L |
| Manganese | 0.3 mg/L |
| Sodium | No designated limit ** |
| pH | No designated limit |
| Hardness | No designated limit |
| Alkalinity | No designated limit |
| Turbidity | 5 NTU |
– mg/L means milligrams per liter
– MCL defines the highest concentrations of contaminants allowed in public water supplies, as set by the New York State Health Department and the Environmental Protection Agency (EPA).
– NTU means Nephelometric Turbidity Units
**More than 20 mg/L of sodium should not be used for drinking by people on severely restricted sodium diets. More than 270 mg/L should not be consumed by people on moderately restricted sodium diets.
Also test for contaminants that might be located in your area. For example, test for volatile organic chemicals (VOCs) if oil, petroleum, or solvents are stored nearby or if there has been a spill, or for pesticides and herbicides if a well is located close to an area used for agriculture. Contact the TCHD if you have any questions.
