Drinking Water Sampling

In the environment, nitrite generally converts to nitrate, which means nitrite occurs very rarely in groundwater. Nitrate is predominately used in fertilizer for plant growth. Nitrite is used for curing meats. Testing labs generally analyze for nitrate and nitrite together so the results are often written as nitrate+nitrite as N.

The drinking water standard for nitrite-N is 1.0 mg/L and for nitrate-N is 10 mg/L. Natural levels of nitrate-N vary from ' to 4 mg/L. If the value is above 4 it is possible that nitrate-N is moving into groundwater from surface land use or a septic system. Nitrate exceeding 8 mg/L are approaching the health standard and should be monitored regularly if an infant under 1 year of age is using the water. Nitrate-N values over 10 mg/L are unsatisfactory and action should be taken to determine the source and discontinue use of water for infants and people with cardiac problems.

The major risk is for infants under 6 months of age. Nitrate in the body is transformed to nitrite, which can bind to hemoglobin (the oxygen carrier in blood) and prevents transport of oxygen. The result is a decreased oxygen supply, often called blue baby syndrome (methemoglobinemia). The skin often turns blue or gray in color, especially around the mouth and requires immediate medical attention.

Nitrate is found naturally in soil and water in low concentrations of less than 4 mg/L. However common sources of nitrate contamination include septic systems, refuse dumps, fertilizers, manure and decaying plant matter. Nitrate carried into groundwater from the surface and is an early indicator that pollution is reaching the water supply.

SAMPLING PROCEDURE:

1. Obtain a 250 mL Neutral sampling bottle from Department.
2. Collect sample from a non-swivel faucet with aerator removed.
3. Run cold tap water for 3-5 minutes to flush pipes.
4. Remove bottle cap and fill the sample bottle up to the neck.
5. Replace cap and secure tightly to prevent leaking.
6. One bottle can be used for both the nitrate and nitrite tests for the same sampling site.
7. Fill out the Customer Mailing Address, email, and phone number. Write in the date and time the sample was collected, relevant sample site information, and water type (e.g., well, surface, or other description). Write in PRIVATE when testing a private well.
8. Record water temperature and chlorine residual (if it applies) if known. Submit sample to Department for testing the same day tested as this test has a 48 hour hold time and must be received before then for the sample to be valid.

Additional Information

Water Tests and Results

• Well Educated Total Coliform and E.Coli 

Well Operation & Maintenance

• How Well Do You Know Your Well

• Color Wheel

• CDC: Disinfection of Drilled or Driven Wells After an Emergency
• Cistern and Other Rain Catchment Systems
• CDC: Make Water Safe

• Shocking a Well

• EPA Ground Water and Drinking Water
• Bacteria in Water Wells

Lead has been found in natural waters, but usually lead in drinking water comes from plumbing. The degree to which lead from pipes, solder, and fixtures will corrode and introduce lead into drinking water depends on the corrosive properties of the water. Dissolved oxygen and low pH are common causes of lead corrosion. In older homes, lead pipes were commonly used for plumbing.

More recently, lead solder was used to make connections between copper pipes up until regulations were put in place in the 1980s, restricting the use of solders containing lead. Lead is not detectable in water by smell, taste, or sight. If you suspect corrosion of lead plumbing in the drinking water, it is a good idea to have the first draw of your water tested immediately after the tap has been turned off for 12 hours.

The US Environmental Protection Agency has set 0.015 mg/L as a drinking water standard for lead. Higher concentrations can cause kidney damage, high blood pressure, and brain damage. Effects can be more severe in children and may cause delays in physical and mental development.

SAMPLING PROCEDURE:

1. Obtain a 1 Liter bottle for Metal sampling from Department.
2. Let water sit overnight without running the tap and collect the first draw sample in the morning without flushing the pipes.
3. Remove faucet aerator.
4. Remove bottle cap and fill the sample bottle up to the neck.
5. Replace cap and secure tightly to prevent leaking.
6. Fill out the Customer Mailing Address, email and phone number. Write in the date and time the sample was collected, relevant sample site information, water type (e.g., well, surface, or other description), and temperature of water if known. Write in PRIVATE when testing a private well.
7. Record water temperature if known.
8. Submit sample to Department for testing.