Monday, May 30, 2016

VDH Tests the Wells on Possum Point Road

Last winter after initially offering the service for around $1,200 the Virginia Department of Health (VDH) decided to sample and analyze at the Department’s expense the private drinking water well of any of the 24 homeowners adjacent to the Dominion Power Possum Point Plant. This is the Prince William County power plant where Dominion Power has been moving forward with a plan to “close in place” 3.7 million cubic yards of coal ash under the new U.S. EPA Coal Ash regulation. The plan for Possum Point is to consolidate all of the on-site coal ash into one impoundment. Dominion has collected more than 1 million cubic yards of ash from four smaller ponds; put them into the large 120-acre pond that already contains 2.6 million cubic yards of coal ash that they have begun to dewater. Ultimately, the pond will be capped with an impermeable membrane to prevent future infiltration of rain.

However, these coal ash ponds have been open to the elements and taking on water for decades. There is concern that trace contaminants and metals in the coal ash may have already leached into the groundwater, Quantico Creek and Potomac, though the residential wells are all up gradient (the groundwater naturally flows to the bay) of the coal ash ponds and separated by an tributary known to the residents as “Beaver Pond” which would under most circumstances act as a hydraulic barrier between the coal ash ponds and the residences. In other words the hydrology of the area would tend to act to protect the homeowners’ wells from contamination for the power plant. In addition, groundwater in Prince William County tends to be very “young” depending on the depth of the well.

Our modern world is filled with chemicals, they exist in pharmaceuticals, household products, personal care products, plastics, pesticides, industrial chemicals, human and animal waste and yes coal ash ponds; they are in short, all around us. According to the Toxic Substances Control Act (TSCA) inventory of chemicals there are more than 84,000 chemical substances. Under the authority of the Safe Drinking Water Act (SDWA), EPA sets standards for approximately 91 contaminants in drinking water including bacteria from human waste, industrial discharge streams and water disinfection by-products and distribution system contaminants. For each of these contaminants, EPA sets a legal limit, called a maximum contaminant level (MCL). EPA requires that all public water supplies be tested for this list of contaminants on a regular basis (from daily, to quarterly, to every other year or longer depending on the contaminant and water system) and meet these minimum standards on average. In addition, EPA sets secondary standards for less hazardous substances based on aesthetic characteristics of taste, smell and appearance, which public water systems and states can choose to adopt or not.

While the U.S. Environmental Protection Agency (EPA) regulates public water systems, making the imperfect United States public water systems the safest and cleanest on earth there are no regulations for private drinking water wells. The responsibility for ensuring the safety and consistent supply of water from the estimated more than 21 million private wells belongs to the well owner. These responsibilities should include knowing the well’s history, testing the water quality annually (or more often as needed), and having the well system and its components inspected regularly by a well driller licensed or certified. In Virginia that is the Department of Professional and Occupational Regulation, DPOR. Regulations for wells in Virginia have only been in effect since 1992 and only address the construction of the well not the safety or quality of the groundwater. However, there are no regulations in Virginia to make you test or care for your private well. Most home owners do not test their wells. Though there are reported to be 1.5 million Virginian who depend on a private well for their drinking water, the Virginia Rural Household Water Quality program that subsidizes the costs tests less than 1,500 wells a year, and only 6 of the 24 well owners on Possum Point Road chose to have VDH test their wells.

Groundwater aquifers are potentially vulnerable to a wide range of man-made and naturally occurring contaminants, including many that are not regulated in drinking water under the SDWA, which defines a contaminant as “any physical, chemical, biological, or radiological substance or matter in water.” This is a very broad definition of contaminant includes every substance that may be found dissolved or suspended in water, everything but the water molecule itself. Drinking water contains much more than just the water molecule, there are minerals and metals and traces of many other substances. One of the more surprising facts about water is that all the water on Earth is about 4.5 billion years old, dating form when the earth was formed.

Slowly, the waters of earth have picked up traces of its journey through time and the planet. However, the SDWA only has MCLs and secondary standards for 91 contaminants that have been found to impact many public drinking water systems. Some substances have non-regulatory human health screening levels and then there are substances where no screening level has been determined. The presence of a contaminant in water does not necessarily mean that there is a human-health concern. Whether a particular contaminant in water is potentially harmful to human health depends on the contaminant’s toxicity and concentration in drinking water. Other factors include the susceptibility of individuals, amount of water consumed, and duration of exposure.

Several of the substance controlled under the SDWA are natural occurring contaminants, 6 are bacteria and 8 are by-products or additives of water treatment; however, though most contaminants in water are naturally occurring, the greatest problem is pollution caused by mankind. Anthropogenic pollutants contaminate surface and groundwater as a result of manufacturing, combustion and incinerations air emissions, landfills and spills, stormwater runoff carrying agricultural and surface pollutants and waste water treatment water carrying a wide range of chemical containing substances into surface water and groundwater.

Only 6 of the 24 homeowners on Possum Point Road were interested in having their water wells tested by the VDH. The methodology used by the VDH was different from what we do when we sample in the Rural Household Water Quality Program because our purposes are different. Our program is interested in identifying bacterial contamination, matching water quality to household treatment options and measuring the impact of the household plumbing on the drinking water. Our methods are designed for that and require a fist draw for our water clinics. This year our clinic’s samples were analyzed for: iron, manganese, nitrate, lead, arsenic, fluoride, sulfate, pH, total dissolved solids, hardness, sodium, and copper, total coliform bacteria and E. coli bacteria. These are mostly the naturally occurring contaminants and common sources of contamination: a poorly sealed well or a nearby leaking septic system, or indications of plumbing system corrosion.

The VDH was looking to take water samples that represent the underlying aquifer. The wells were sampled by the health department on three different days; on February 23rd 2016 (1 well), March 1, 2016 (4 wells) and March 7th 2016 (1 well). All the wells were sampled from an outdoor spigot or tap before treatment close to the well head after purging 20 gallons (in one instance), 40 gallons (in 4 instances) or 44 gallons (in one instance). The goal was to test the underlying aquifer not the impact to water sitting in pipes for several hours. While this method would likely reduce impact from piping, it is unlikely that flushing 20-44 gallons would flush the water from the well column so the lead they found present in the 4 wells with acidic water was likely from the well and pump fittings which historically have contained up to 8% lead in the brass. Well columns contain (typically) about 1.5 gallons per foot so it is most likely that the VDH was sampling water that had been stored in the well for an unknown period of time.

This brings up a weakness in the information. There is no information provided about the wells themselves. The type, age, depth of the well, and the recharge rate are unreported. Four of the six wells had water that was slightly acidic and though the flushed water samples from the point tested was below the MCL for lead of 15 ppb, as the VDH points out there are many who believe that there is no safe level for lead, especially since the VDH for the most part tested an outdoor spigot and did not measure the impact of the household plumbing to flushed lead levels. We find in our water clinics that elevated levels of lead often occur in homes with acidic water. While the presence of low levels of lead in the home with acidic water (a pH of 4.85-5.79) is of concern for long term health of the occupants, it is not an indication of impact from the Dominion coal ash ponds. This commonly occurs throughout the county and the Commonwealth. Other findings of concern were VDH discover that one of the wells had a large opening in its lid which presents a significant contamination risk for bacterial contamination as well as insects and small animals. Another well was reported to be in the basement of the home. This well does not meet the current state well construction regulations or the old 1979 county well regulations. Finally, there were significant elevations of sodium, sulfate, iron, and manganese substances that are naturally occurring and can make well water quite unpleasant.

The VDH tested the water for thirteen contaminants that are regulated under the Safe Drinking Water Act (arsenic, barium, beryllium, cadmium, total chromium, mercury, lead, antimony, selenium, thallium, radium). Though traces of various substances were found, none of the levels of contaminants were above the MCLs or SMCLs of the Safe Drinking Water Act so would be acceptable for public drinking water supplies. The VDH also tested for substances not regulated under the Safe Drinking Water Act. These contaminants were: boron, calcium, cobalt, lithium, magnesium, sodium, nickel, vanadium, zinc, alkalinity, bicarbonate alkalinity, carbonate alkalinity, hexavalent chromium, molybdenum, strontium, thorium, radium-228 and vanadium. The chart below shows the summary of results of what they found (you can request the information under the FOIA).

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