Health Department column: Wells and your drinking water

Published 12:08 am Saturday, June 6, 2015

By Tad Helmstetler

Rowan County Health Department

Approximately 50 percent of Rowan County’s citizens rely on private drinking water wells for their water needs. Currently, the standard well in the county is the six-inch drilled well. These wells provide good quantities of safe water and are easy to repair.

Some older well types in the county are the two-inch well and the bored well. Two-inch wells consist of a two-inch pipe driven 50 to 70 feet in the ground. A foot valve located at the bottom of the well controls water flow. Replacing an inoperable foot valve requires pulling the entire pipe. If the pipe has rusted and breaks while being pulled the well is ruined.

Bored wells are 12 to 30 inches in diameter and are lined with cement or terra cotta pipe with unsealed joints. They are usually no deeper than 60 feet. Water yield is low, and they are prone to going dry in drought conditions. The unsealed pipe joints can be infiltrated by surface water, which causes bacterial contamination.

The state of North Carolina has had rules regarding the construction of private water supply wells since the 1970s, but there was no permitting or inspection process tied to these rules for some time. Rowan County has had enforceable well regulations since 2007.

Groundwater contamination can occur many ways. One of the most common is bacterial contamination. The act of constructing the well and placing the pump introduces bacteria into the water supply. Infiltration of surface water into the subsurface water supply can also lead to bacterial contamination. Post-construction chlorination of the well is required to eliminate bacterial contaminants. Sometimes the initial chlorination is not successful, and additional chlorination is required.

Well water is also tested for inorganic chemical constituents. A typical inorganic sample checks for pH, alkalinity, fluoride, chloride, calcium, magnesium, total hardness, manganese, lead, arsenic, copper and nitrates. High levels of these substances can result in damage to plumbing, inability to wash clothes and severe health effects on children and adults.

Lead and manganese are neurotoxic and can cause brain damage in children and psychological disorders in adults. Arsenic is carcinogenic in high concentrations. Copper is necessary for human metabolism, but in excessive amounts, it can cause gastrointestinal symptoms such as nausea and diarrhea. Fluoride helps protect children’s teeth in the proper amount, but larger doses can leave children with mottled, gray teeth. Hard water prevents detergent from working properly in the laundry. Nitrates are present in the water from agriculture. They are used in fertilizer. Large doses of nitrates can cause a condition known as methemoglobinemia or “blue baby” syndrome.

Some wells can become contaminated by petroleum products or pesticides leaking underground. Storage tanks can contaminate wells in a wide radius from the actual tank. Pesticides can get in well water through improper application of the pesticide or improper storage of the pesticide. Never store any type of chemical or fuel product inside a well house. Accidents can happen.

Recently, water contamination near the Buck Steam Station has been reported. Testing mandated by the Coal Ash Management Act of 2014 detected private drinking water wells with levels of vanadium and hexavalent chromium. Both of these heavy metals are used in industry and also occur naturally. Both metals are considered toxic at higher levels. Further testing will be done on these wells, and the North Carolina Laboratory of Public Health is working to develop a test kit for these metals that will allow the Rowan County Health Department to offer this test to concerned residents who live near the Dukeville area, but are outside the 1,500-foot testing radius.

For Rowan County residents with older wells which have not been tested, Rowan County Environmental Health offers testing for a wide variety of chemical constituents. Applications can be made at Rowan County Environmental Health located at 402 N. Main St., Suite 106 in Salisbury. There are fees associated with testing, and a complete list of fees is available by calling 704-216-8525.

For residents interested in learning more about the process of well drilling, drinking water, and the various substances found in groundwater, the Rowan County Health Department will be sponsoring a community information session on June 30 at the Agricultural Center located at 2727 Old Concord Road from 5 p.m. to 7 p.m. The session will be free and all citizens are invited to attend.

More information about private well drinking water contaminants can be found on the Well Water and Health website: http://epi.publichealth.nc.gov/oee/programs/wellwater.html

 

Tad Helmstetler is the environmental health supervisor with the Rowan County Health Department.