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Released 2/10/04 -
WQA on USEPA Pilot Studies
USEPA researchers report that scales and films in drinking
water supply pipes can accumulate and leach high levels
of contaminants
USEPA personnel reported disturbing
drinking water distribution system revelations at the Inorganic
Contaminants Workshop sponsored by the American Water Works
Association on February 1-3, 2004.
.....Agency field engineers have been discovering that "regulated
inorganic and radiological contaminants present in source
water above detectable [analytical detection levels] but
less than the safety standard, can accumulate in distribution
systems to a significant number of times above their respective
standard and that this is a largely unknown, unexplored,
and universal phenomena."
.....In other words, though the water leaving a municipal
treatment plant complies with all USEPA criteria, events
occurring in the water distribution system after water leaves
the plant can lead to significant spikes in contaminant
levels.
.....Case histories were reported in which scales and biofilm
that sheared off or otherwise leached from pipe walls have
caused drinking water levels exceeding tens and thousands
of milligrams per liter for iron and copper and exceeding
hundreds of micrograms per liter as well for arsenic, lead,
zinc, and manganese-well above levels considered safe for
consumption.
.....This same phenomenon occurs with radium and causes
two distinct problems:
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1.
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Radium in pipe deposits
far exceeds the Safe Drinking Water Act MCL of 5 picoCuries
per liter. |
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2.
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Radium decays to radioactive
radon, which is released into the flowing water supply. |
.....One USEPA researcher reported that scales in household
plumbing could literally cause the home's water pipe system
to exceed the federal government's toxicity characterization
leaching procedure (TCLP) limits-making those deposits,
by definition, a "hazardous waste"!
.....Another meeting report noted a related adverse reaction
in household plumbing that is actually being created by
the increasing use of chloramination for public water system
disinfection. Chlorine typically dissipates from chloramines
as water resides in home water pipes. This auto-decomposition
creates ammonia, which can then change to nitrites. This
"nitrification" lowers water pH in low alkalinity
waters-which can lead to iron and copper corrosion in home
plumbing.
.....WQA Technical Director Joseph F. Harrison,
P.E., CWS-VI says, "Water Quality Association supports
the need for further research into the public health significance
of these discoveries. We also urge new research into all possible
remedies, such as more effective central treatment and control
schemes and the feasibility of using of point-of-use and point-of-entry
(POU/POE) water treatment approaches inside the home to provide
safeguard barriers for consumers' public health protection."
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