Yesterday morning following the instructions from the Extension
Office, I collected water samples from my kitchen sink and put the sample
bottles in the refrigerator. Then after having coffee and feeding the animals I
drove the samples (in a insulated lunch pack on ice) to the Extension Office in
Manassas. Once a year the Virginia Cooperative Extension in Prince William
County holds a well water testing clinic where water samples are tested for: iron,
manganese, nitrate, lead, arsenic, fluoride, sulfate, pH, total dissolved
solids, hardness, sodium, copper, total coliform bacteria and E. Coli bacteria
all for the low cost of $65. I test my well every year and the Extension
program is one of the cheapest ways to get it done. Judging by the number of people who
participate in the clinic each year (a hundred or so out of thousands of well
owners in Prince William County) most people do not test their well regularly. You
should.
While the U.S. Environmental Protection Agency (EPA)
regulates public water systems, the responsibility for ensuring the safety and
consistent supply of water from a private well belongs to the well owner-in
this case me. These responsibilities should include knowing the well’s history
and planning for equipment replacement , 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 well service company.
In
Virginia installation of private wells is regulated by the Department of Health,
responsible for approving the location of a well, inspecting the well after
construction to verify proper grouting and adequate water yield, maintaining
records of the well driller’s log, verifying the most basic potability of water
by requiring at a minimum bacterial testing after completion. Then you are on
your own to do what you deem best.
If your home has a drinking water well that is contaminated,
it could significantly impact your health and the value of the property. When
you buy a home lenders require that a well be tested for coliform bacteria
contamination, nothing more. For many homeowners this was the only time
their well was ever tested. Total coliform bacteria is always present in manure
and sewage, but is also present in soil and vegetation and surface water. The
presence of coliform bacteria can mean that surface water is getting into the
well either directly through a failing casing or grouting or improper
construction or well cap or by other means. Absence of coliform bacteria only
means that water is not contaminated by septic and surface runoff, but the
water might be contaminated from other sources.
Due to its protected location underground, most groundwater
is naturally clean and free from pollution. Typically, the deeper the well the
less likely is it to be contaminated; however, there are a number of threats to
drinking water: improperly disposed of chemicals (pesticides and oil poured
down the drain of a home with a septic system); animal wastes; pesticides;
human wastes (that nearby septic system); wastes buried underground or leaking
fuel tank; and naturally-occurring substances can all contaminate drinking
water and make it unsuitable for drinking or make the water unpleasant to
drink. Homes built on former disposal sites- farm dumps, landfills or former
military operations are particularly susceptible to contamination. Former
agricultural properties should be tested for pesticides, fuels and solvents
because farmers often have fuel tanks and repaired farm equipment with solvent
that were improperly disposed of over the years. Hopefully, all those tests
were done before you bought the home (I know I did).
The nightmare scenario is what happened in Sterling,
Virginia. The short story is that for twenty or thirty years homeowners in that
community in in Loudoun County were drinking water contaminated with TCE and
its degradation products. The homes had been built on and old landfill and back
in 1988 the Loudoun County Department of Health and the EPA had found traces of
TCE, its degradation products and pesticides in three residential wells, but
because the contamination was below the regulated maximum contaminant level
(MCL) no further investigation was performed. Apparently, the oddity of finding
a solvent in groundwater in a residential community did not immediately prompt
further investigation. The water was within safe limits and thus was fine.
However, the water in the neighborhood was not fine. In
2005, 68 more wells (in the community) were tested by the Health Department.
“Forty-five wells tested positive for TCE; 17 of these wells contained
concentration of TCE above the maximum contaminant level (MCL) of 5 micrograms
per liter (mcg/L) while 28 wells contained TCE, but below the MCL.” The
site was declared a CERCLA (Superfund) site in 2008. Between 1988 and 2005 no
testing was done on the individual homeowner wells. The water was consumed by
the young and old and the homes were bought and sold. If your home had been
declared within a Superfund site, it is very likely that the value of the home
would be impacted.
Everything that is known about the groundwater in Prince
William County is because a study of the groundwater was performed by the U.S.
Geological Survey (USGS) in 1991 to study the extent of TCE contamination from
the Superfund site in Manassas. They did not test every inch of the county nor
look for other contaminants, but felt that they were able to find the extent of
the TCE contamination plume. To be prudent and smart you need to test a well
for likely sources of contamination. When I was working as an Environmental
Engineer, the biggest challenge was to adequately research the history of a
property and then test the soil and groundwater for contamination in the
areas most likely to be contaminated. Testing is expensive, so it is
virtually impossible to fully test soil and groundwater for everything and it
is very easy to miss the contamination if the study is not planned properly and
you do not understand the geology.
When buying a single family home, you do not have any of
this information or resources available to you. Neighbors can be useful or just
have no understanding of environmental and groundwater issues and tell you
nonsense they’ve heard. If someone asked me about groundwater in my community
or my opinion about any specific well, I would tell them, but they would not
know my level of expertise. While there are some good historical records
available for industrial and commercial properties there is very little
information available for residential properties. The department of health
often has some useful information about water quality in the county and septic
systems, but rarely has any water analysis data available. Though, it was a
Department of Health employee who originally found the Prince William County
TCE contamination.
Your best option is to do a broad scan of the well water
quality. There are screening packages available from U.S. EPA certified
laboratories like National Testing Laboratories that screen water wells
for all the primary and secondary contaminants in the Safe Drinking Water Act.
The WaterCheck with pesticides package from National
Testing Laboratories is a broad stroke test, testing the water for 103 items
including Bacteria (Total Coliform and E-Coli), 19 heavy metals and minerals
including lead, iron, arsenic and copper (many which are naturally occurring,
but can impact health); 6 other inorganic compounds including nitrates and
nitrites (can indicate fertilizer residue or animal waste); 5 physical factors
including pH, hardness, alkalinity; 4 Trihalomethanes (THMs) and 47 Volatile
Organic Chemicals (VOCs) including Benzene, Methyl Tert-Butyl Ether (MTBE) and
Trichloroethene (TCE). The pesticide option adds 20 pesticides, herbicides and
PCBs. This testing can be done for a few hundred dollars.
I’ve done that kind of “full analysis” on my well a few
times. These days I test my well annually in the annual water quality clinic
sponsored by the Extension office. Groundwater quality is driven by geology,
well construction and condition, nearby sources of groundwater contamination,
and any water treatment devices and the condition and materials of construction
of the household plumbing. Year to year, outside sources of groundwater
contamination are not likely to change except with changes in land use. Thus,
it is not necessary to test for industrial contaminants every year. To ensure my
drinking water remains safe it is important to maintain my well (I replaced the
cap two years ago), test it regularly and understand your system and geology. I
do not have any water treatment in my house, I drink the water just as it is
from the ground. If however, you have water treatment equipment in your home
you might want to get test the water before and after the treatment equipment each
year to make sure you have the right equipment for your water and that it continues
working properly.