Transcript Regulatory Cost-Benefit Analysis & Ground Water Rule

PROPOSED
GROUND WATER RULE
HOW WILL IT AFFECT YOU?
OVERVIEW
• Background
• Baseline Information
• Proposed Regulatory Provisions
BACKGROUND:
STATUTORY AUTHORITY
SDWA 1996
Subsection 1412(b)(1)(A): “The Administrator shall, …
promulgate a national primary drinking water regulation
(NPDWR)…if the Administrator determines that the following:
(i) the contaminant may have an adverse affect in the health of
persons;
(ii) the contaminant is known to occur or there is a substantial
likelihood that the contaminant will occur in public water
systems with a frequency and at levels of public health concern;
and
(iii) …regulation of such contaminant presents a meaningful
opportunity for health risk reduction…
Section 1412(b)8: “…the Administrator shall also promulgate
NPDWR requiring disinfection … as necessary, (for ground
water systems.”
• Contaminants of Concern in Ground Water
are:
• Viral pathogens
Type A (highly infectious, generally causing mild
illness): Rotavirus, Norovirus, Adenovirus
• Type B (generally less infectious, causing severe
illness): Enteroviruses (e.g. Echovirus,
Coxsackieviruses, Polioviruses; Hepatitis A virus
(HAV))
• Bacterial pathogens
E. coli O157:H7, Salmonella, Campylobacter,
Shigella
SOURCES OF MICROBIAL
CONTAMINATION TO WELLS
• MALFUNCTIONING SEPTIC
SYSTEMS
• LEAKY SEWER LINES
• ANIMAL WASTE RUNOFF
• STORMWATER RUNOFF
• SURFACE WATER
• Health Effects of Pathogens
– Illnesses and deaths caused by viral and bacterial pathogens
• Gastroenteritis – most common (approx. 200 million gastrointestinal illness
per year)
• Other acute illnesses –
– Hepatitis A (HAV e.g., Lancaster Co. PA)
– Kidney failure (E. coli O157:H7 e.g., Walkerton, Ontario;
Washington County Fair, NY; Cabool, MO);
– Bloody Diarrhea (Shigella e.g., Island Park ID);
– Acute gastrointestinal illness with vomiting (Norovirus
e.g., Atlantic City, WY);
– Guillian-Barre paralysis (Campylobacter);
– Meningitis Enteroviruses (e.g., Switzerland)
• Chronic illness - kidney disfunction (E. coli O157:H7), reactive arthritis
(Campylobbacter), diabetes (Coxsackievirus), myocarditis (Enteroviruses)
– Sensitive sub-populations
• This population includes very young children, elderly, immunocompromised
(e.g., individuals living with AIDS, transplant recipients, individuals receiving
chemotherapy, etc.)
• These individuals are more likely than others to suffer serious illness for
longer periods
BACKGROUND:
PUBLIC HEALTH RISKS
• CDC Outbreak Data – 1971-1996
– Approx. 640 outbreaks, 168K cases of illness (excl. Milwaukee)
• 371 (58%) outbreaks; 54% illness associated with GWS
• Sources
 54% from contamination in untreated groundwater;
 38% in systems providing treatment;
 5% distribution systems contamination;
 3% miscellaneous/unknown
• Occurrence Studies
– 13 independent studies
– AWWARF study most comprehensive and hydrogeologically
representative (448 wells sampled in 35 states)
– Conservative analysis suggest fecal indicators detected in 2%15% of wells
More Recent Data
• CDC Outbreak Data – 1991-2000
– Approx. 140 outbreaks, 30K cases of illness (excl.
Milwaukee)
• 68 outbreaks; 11K cases of illness associated with GWS
• Sources
 41% from contamination in untreated groundwater;
 38% in systems providing treatment;
 16% distribution systems contamination;
 4% miscellaneous/unknown
Overview: Baseline Information
NUMBER OF GWSs BY TYPE and
NUMBER OF PEOPLE SERVED BY TYPE
Ground Water Systems
People Served
42,361
(29%)
CWS
9 M (8%)
5M
(5%)
CWS
NTNCWS
NTNCWS
TNCWS
TNCWS
100 M
(87%)
86,061
(58%)
Total: 147,330 Systems
Total: 114 M People
80% of TNCWS do not disinfect
70% of NTNCWS do not disinfect
40% of CWS (serving <500 people) do not disinfect
BASELINE INFORMATION:
STATE DISTRIBUTIONS
2112
3894
1792
1229
447
1910
1498
7832
2404
1965
11450
566
626
1290
580
9548
4983 4237
1634
2981
1808
832
5044
5238
897
751
2485
4043
556
3674
3186
0
290
7105
1430
1204
938
609
1249
710
1403
1333
5420
424
2302
1612
6421
113
12
8
127
American Samoa
Guam
N. Mariana Islands
271 Puerto Rico
4
Virgin Islands
902 Tribes
Ground Water Systems per State
Fewer than 500 (5)
500-1,000 (9)
1,001-8,000 (32)
More than 8,000 (4)
September 2002 SDWIS data
461
9038
11872
D.C.
• Ground Water Systems of Concern:
– 20 million people served by undisinfected GWS
• 10 million from CWS
• 10 million from NCWS
– Disinfecting systems with treatment
deficiencies or failures
• Inadequate storage
• Insufficient operator training
HOW MANY SYSTEMS AND PEOPLE IN
NEW ENGLAND WILL THE GWR
AFFECT?
• APPROXIMATELY 10,061 SYSTEMS
• (ABOUT 90% OF TOTAL)
• SERVING 4,132,913 PEOPLE IN SIX
STATES
• [SOURCE: SDWIS (September 2004)]
GENERAL OVERVIEW OF
GROUND WATER RULE
• Builds on existing State Programs
• Targeted, risk-based approach; no mandatory
disinfection
• Provides State with flexibility (defining
significant deficiencies, hydrogeologic
evaluations, corrective action approach)
PROPOSED REGULATORY PROVISIONS:
MULTI-BARRIER APPROACH
Sanitary
Survey
Compliance
monitoring
Source
Water
Monitoring
Corrective
Actions
Sewer Line
Sensitivity
Assessments
PROPOSED GWR PROVISIONS
Sanitary Surveys
– Evaluate 8 elements
– Conduct every 3 years
for CWS; 5 years for
NCWS
– Identify significant
deficiencies
– Require corrective
action
SIGNIFICANT DEFICIENCIES
•
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•
•
•
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•
•
Source
Treatment
Distribution System
Finished Water Storage
Pumps, Pump Facilities and Controls
Monitoring, Reporting & Data Verification
System Management and Operation
Operator Compliance With State
Requirements
PROPOSED GWR PROVISIONS
Hydrogeologic Sensitivity
Assessment
– Systems that do not provide
treatment (4-log
inactivation/removal of
viruses)
– Sensitive: karst, gravel,
fractured bedrock or other
– Complete by 6th year
(CWS), 8th year (NCWS)
– State may evaluate
hydrogeologic barrier
FACTORS AFFECTING MICROBIAL
INACTIVATION
AND TRANSPORT IN SUBSURFACE
• TEMPERATURE
• METAL HYDROXIDE (IRON, ALUMINUM,
MANGANESE) CONCENTRATION
• MICROBIAL SIZE AND ISOELECTRIC
PROPERTIES
• FLOW VELOCITY
• PH
• DEGREE OF SATURATION
• NATIVE MICROBIAL TYPE AND DISTRIBUTION
• IONIC STRENGTH OF GROUND WATER
• GRAIN SIZE AND AQUIFER HETEROGENEITY
PROPOSED GWR PROVISIONS
Source Water
Monitoring Indicators
• State selects one fecal
indicator:
– E. coli
– Enterococci
– Coliphage (male
specific or somatic
coliphage)
PROPOSED GWR PROVISIONS
Routine Source Water Monitoring
– Hydrogeologically sensitive sources
– Monthly for at least one year
– State may reduce to quarterly or waive
altogether
– Repeat sampling to waive corrective action
• Objective:
– Identify fecal contamination at source, and if found,
require corrective actions for systems with sensitive
aquifers (karst, gravel, fractured bedrock) and less than
4-log treatment for viruses
• How does it work?
– Systems with a sensitive aquifer must collect 12
monthly source water fecal indicator samples
– Samples must be collected within 3 years
– Systems with a fecal positive indicator must take
corrective action (e.g., disinfection, well remediation,
or elimination of contamination source if identified)
• Why is this a good requirement?
– The most prominent ground water related
outbreaks have occurred in sensitive
aquifers and this provision improves the
likelihood for avoiding such outbreaks
– Identifies and targets wells that are most
easily contaminated
– Compensates for infrequent monitoring
under the triggered monitoring provision
because fecal contamination can be highly
intermittent and difficult to detect
PROPOSED GWR PROVISIONS
Triggered Source Water Monitoring
– Systems that do not provide treatment (4-log
inactivation/removal of viruses)
– Triggered by a total coliform positive sample under
the Total Coliform Rule
– Must collect and analyze source water sample within
24 hours
• Objective:
– Identify fecal contamination originating in source water
and if found, require corrective actions for systems with
less than 4-log treatment for viruses
• How does it work?
– Systems monitor for total coliforms in the distribution
system under existing Total Coliform Rule (TCR)
– Systems with a total coliform positive must sample
their source water for a fecal indicator
– Systems with a fecal positive indicator must take
corrective action (e.g., disinfection, well remediation,
or elimination of contamination source if identified)
• Why is this a good requirement?
– Inexpensive source water monitoring approach that will
build on existing rule
– Pertains to all wells
PROPOSED GWR PROVISIONS
Corrective Action
– IF a GWS
• has a significant deficiency identified, OR
• detects a State-specified fecal indicator in source water
– THEN
• it must take corrective action ASAP, but not later than
120 days, or on a State approved schedule
– System consults with State about appropriate corrective
approach
– Correct action approaches include the following:
• correct significant deficiency
• eliminate source of contamination
• provide alternate source of water
• 4-log inactivation or removal of viruses
PROPOSED GWR PROVISIONS
Compliance Monitoring
– Chemical disinfection – system
monitors disinfectant residual
• continuously for systems serving
3,300 or more persons
• daily for systems serving less
than 3,300 persons
– UV Disinfection – system
monitors UV irradiance level
continuously
– Membrane filtration – system
must ensure membrane is intact
and operated in accordance with
State specified criteria.
NEXT STEPS
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OMB Review and Comments by July 2006
HQs Response to Comments
Final Rule: August, 2006
Complete guidance documents for States
and public water systems
IMPLEMENTATION
ASSISTANCE
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Quick Reference Guide
Rule Training
Guidance Manuals
Collaboration with Various Partners
?NEED MORE INFORMATION?
• General Information
– EPA’s Safe Drinking Water Hotline:
1-800-426-4791
– Website: http://www.epa.gov/safewater
• Ground Water Rule in New England
– Regional Contact: Doug Heath
• E-mail: [email protected]
• Office: 617-918-1585