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In the News…
Public Health and Drinking Water News Briefs
| December 23,
2005 |
| Two
New EPA Drinking Water Regulations in Effect |
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The U.S. Environmental
Protection Agency (EPA) announced that it has finalized two drinking
water protection rules - one that reduces the risk of disease-causing
microorganisms from entering water supplies and another that requires
water systems to limit the amount of potentially harmful disinfection
byproducts (DBPs) that enter the public water supply through disinfection
processes. Finalizing the two rules represents the last phase
of a congressionally required rulemaking strategy under the 1996
Amendments to the Safe Drinking Water Act.
The "Long Term
2 Enhanced Surface Water Treatment Rule" (LT2), increases monitoring
and treatment requirements for water systems that are prone to outbreaks
of Cryptosporidium. The rule requires that public water systems
that are supplied by surface water sources monitor for the waterborne
pathogen. Those water systems that measure higher levels of Cryptosporidium,
or do not filter their water, must provide additional protection
by using options from a "microbial toolbox" of treatment and management
processes.
Cryptosporidium
causes gastrointestinal illness that can produce serious health
threats in those with weakened immune systems, including infants
and the elderly. It can also be fatal in people with severely compromised
immune systems, such as cancer and AIDS patients.
The second
rule, "Stage 2 Disinfection Byproducts Rule" (Stage 2 DBP) strengthens
public health protection for customers by tightening compliance
monitoring requirements for two groups of DBPs, trihalomethanes
(TTHM) and haloacetic acids (HAA5). Stage 2 DBP targets water systems
that have the greatest risk for high DBPs by using more stringent
methods for determining compliance. Under the rule, water systems
are required to find monitoring sites where higher levels of DBPs
are likely to occur and use these new locations for compliance monitoring.
If DBPs are found to exceed drinking water standards at any of these
new monitoring locations, water systems must begin to take corrective
action.
To read the
complete proposed EPA rules, please go to:
http://www.epa.gov/safewater/disinfection/
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| Wet
Weather Policy to Improve Wastewater Treatment Proposed |
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A new policy
for addressing peak wet weather discharges at wastewater treatment
plants was proposed this week by the U.S. Environmental Protection
Agency (EPA). The agency's aim is to ensure that local governments
use all viable solutions to improve the treatment of wastewater,
protecting human health and the environment during very high or
"peak" flow events at municipal wastewater treatment plants that
are a result of significant storm events.
Many municipal
wastewater treatment systems across the country experience problems
during heavy rains (peak wet weather) when flows to the wastewater
treatment plants exceed the plant's biological treatment capacity.
During peak wet weather, limited "diversions" around biological
treatment units can help prevent raw sewage from being discharged
into our nation's waters, backing up into homes and other buildings,
or damaging biological treatment units. EPA's proposed Peak Wet
Weather policy outlines the limited circumstances when these management
techniques can be used and how they must be documented in National
Pollutant Discharge Elimination System (NPDES) permits.
The proposed
policy is substantially different from the November 2003 proposed
"blending" policy. It requires that discharges still meet all the
requirements of NPDES permits and that public water facility operators
demonstrate that all feasible measures are used to minimize wet
weather problems. It also prohibits the use of these peak flow management
techniques in systems where high peak flows are due to poor system
maintenance or a lack of investment in upgrades to improve treatment
capacity. According to EPA, the policy is designed to provide
greater national consistency while still incorporating flexibility
to recognize site-specific issues.
EPA will accept
public comments on the proposed policy for 30 days after publication.
To read the complete EPA policy proposal, please go to:
http://cfpub.epa.gov/npdes/wetweather.cfm?program_id=0
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| Killing
Noroviruses: A Little Chlorine Goes a Long Way |
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Chlorine is
far more effective at killing noroviruses than previously
believed, according to a recent University of North Carolina study.
Scientists involved in the research confirm that even weak chlorine
solutions can still be used to kill more than 99 percent of noroviruses,
the chief cause of outbreaks of gastrointestinal illness around
the world.
North Carolina
University researchers have discovered for the first time that dilute
solutions of hypochlorous acid, or free chlorine, as low as 20 milligrams
per liter will completely inactivate noroviruses on surfaces
such as stainless steel and ceramic tile. The dilute chemical worked
in five minutes or less. In practice, this means that household
bleach can be diluted by a factor of 1,000 and still provide adequate
disinfection.
Noroviruses
are the leading cause of viral gastroenteritis and have caused numerous
outbreaks of gastroenteritis in health-care facilities, schools,
food establishments, hotels and resorts and on cruise ships. The
North Carolina University researchers presented their findings during
the 2005 International Conference on Antimicrobial Agents and Chemotherapy
in Washington.
For information
from the CDC on Noroviruses, please go to:
http://www.cdc.gov/ncidod/dvrd/revb/gastro/norovirus.htm
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| Chemicals
on Tap in New Drinking Water Survey |
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A recently
released survey conducted by the Environmental Working Group (EWG)
on everyday tap water found 141 unregulated chemicals and an additional
119 for which the U.S. Environmental Protection Agency (EPA) has
set health-based limits.
EWG compiled
findings from states that agreed to provide data they collected
from 1998 to 2003. The data comes from nearly 40,000 water utilities,
serving 231 million people. The utilities were required by federal
law to report that data to consumers. However, a compiled set of
data from all utilities has not been publicly available.
Currently,
the EPA gathers its own water monitoring data reviews the latest
research and looks at treatment methods and technology. States are
also free to set their own safety standards for contaminants that
may not be detected in other states.
EWG's analysis
found almost 100 percent compliance with enforceable health standards
on the part of the nation's water utilities. Under the Safe Drinking
Water Act, EPA has a systematic approach to prioritize and evaluate
additional chemicals for potential regulation, considering both
occurrence data and health effects research.
To read the
complete study, please go to:
http://www.ewg.org/tapwater/findings.php
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In The News-is
a bi-weekly, online service from the Water Quality & Health
Council. The publication is updated every other Friday and can
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