United States
Environmental Protection
Agency
Office of Ground Water
and Drinking Water
Cincinnati, OH
EPA-e 15-M-97-OO2
June 1997
Labcert Bulletin
We're Back
We're back in the swing of things after
a year of cutbacks, lack of travel
funds... Articles in this issue provide
news about: The Ground Water Disinfection Rule;
Method 200.8; the recently promulgated Radio-
nuclide Rule and more. If you have suggestions
for other drinking water certification topics you
would like to see discussed, please call, write, e--
mail or FAX the editors. Please join us in
welcoming back to work and to our staff (not
NERL's), Bob Bordner, who can be reached on
513 569-7932, e-mail bbrdner.bob@epamail.epa.
gov.
EdGlick 513569-7939
e-mail: glick.ed@epamail.epa.gov
Maryann Feige 513569-7944
e-mail: feige.maryann@epamail.epa.gov
Carol Madding 513569-7402
e-mail: madding.caroline@epamail.epa.gov
26 W. Martin Luther King Dr.
Cincinnati, OH 45268
FAX: 513 569-7191
Stakeholders' Meeting On
Privatization Of
Performance Evaluation
Studies
On Tuesday June 3, 1997, a meeting was
conducted by the National Institute of
Standards and Technology (NIST) to
discuss the development of protocols for the
1
In This Issue
| Stakeholders Meeting
on Privatization of Performance
Evaluation Studies
I Method 200.8
| Had Methods Approved
I Streamlining the Method
Approval. Process
I ColilerM 8 Method for Coliforms
and &C&H
I Quanti>-Tray Methods for Total
Coliforms and E.cali
\ New Test for Total Coliforms
and K colt
I Regarding Cyanide
| Update on the Ground Water
Disinfection Rule (GWDR)
I Errata
I Web Sites of Interest
EPA Microbiology Home Page
accreditation of water performance evaluation
study providers.
Many in the laboratory community are aware
that the EPA has been planning to externalize the
water laboratory performance evaluation study
program. The EPA has decided, after
considering public comment, to enter into a
Memorandum of Understanding (MOU) with
NIST. This MOU will delineate the role of
NIST as the performance evaluation study
provider accreditation authority and EPA's role
Printed on Recycled Paper
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as the standard setting authority. Details can be
found in the Federal Register, Vol. 61, No. 139,
Thursday, July 18, 1996.
The last EPA provided study will be shipped hi
1998. After that date, laboratories wishing to be
certified to analyze samples under the Drinking
Water Laboratory Certification Program must
obtain samples as directed by their State.
This change has been necessary due to resource
limitations within EPA. Subsequent Federal
Register notices will contain the text of the MOU
between NIST and EPA and the appropriate
regulatory language changes to the drinking
water regulations.
For information, contact Donna Sirk on 310 975-
3976, fax 310 926-8671 or e-mail donna.sirk
@nist.gov or by calling EPA's Safe Drinking
Water Hotline on 800 426-4791 Monday through
Friday from 9:00 a.m. to 5:30 p.m. Eastern
time.
Method 200.8
We were recently asked to comment
on the acceptability of EPA Method
200.8, Determination of Trace
Elements in Water and Wastes by Inductively
Coupled Plasma - Mass Spectrometry (Rev. 5.4)
to the various regulatory programs. This method
was promulgated for drinking water compliance
monitoring on Jan. 4, 1995 (59 FR 62456) for
various regulated Drinking Water contaminants.
Consult either the CFR or Table IV-2 in the
Fourth Edition of the Manual for the
Certification of Laboratories Analyzing Drinking
Water to determine if this method is approved
for a particular contaminant.
Although this Bulletin is not the forum for
discussing other EPA programs, the following is
our interpretation.
At the tune of this publication, Method 200.8
has been proposed (60 FR 53988, Oct. 18,
1995), but not approved for Waste Water
program analysis on a national level. However,
in 1982 a memo was sent to all U.S. EPA
Regional Administrators by the director of then
EMS (now NERL) stipulating that as far as that
organization was concerned there was nothing
technically wrong with the method and it was up
to each Regional Administrator to determine the
method's acceptability in their Region. Contact
your Regional Waste Water representative for
clarification.
The Solid Waste (RARA) program has its own
JAP-MS method numbered 6020. This method
is approved for use in the program and is
published in SW846, Test Methods for
Evaluating Solid Waste Physical/Chemical
Methods. The Contract Laboratory Program
(CERCLA) also has approved a version of an
IAP-MS method, 6020CLP for use in that
program.
On January 4, 1995, Revision 5.4 of U.S. EPA
Method 200.8, was promulgated for compliance
monitoring of mercury in drinking water.
However, Revision 5.4 can only be used for the
determination of mercury by "direct analysis"
when an acid preserved sample has a turbidity of
< 1 NTU. Unfortunately, when this option (for
the determination of mercury) was added to
Method 200.8, Section 8.1, which addresses
holding times, was not revised to include the
required holding time limitation for mercury of
28 days (CFR 141.23). Please make a note of
this restriction hi your copy of Method 200.8.
The holding tune begins immediately following
the completion of sample collection. For further
information contact Ted Martin, 513 569-7312.
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RAD Methods Approved!!!
The long awaited radionuclide final rule, which approved 66 additional radionuclide analytical methods for
compliance monitoring of drinking waters, was promulgated on March 5, 1997. The methods in the
approved rule were originally proposed in July 1991. This rule does not withdraw any compliance methods
previously approved nor does it change any MCLs or monitoring requirements for radionuclides. A copy
of the Federal Register table is reprinted below. Please note that footnote 11 approves additional calibration
standards for gross alpha determinations. Footnote 12 provides the conversion factor that is omitted in some
uranium mass methods. This factor is required to convert mass (microgram) measurements of uranium to
picoCuries.
Approved Methods for Radionuclide Contaminants
Contaminant
Naturally occurring
Gross alpha" and beta
Gross alpha"
Radium 226
Radium 228
Uranium12
Man-made
Radioactive cesium
Radioactive iodine
Radioactive Strontium
89, 90
Tritium
Gamma emitters
Methodology
Evaporation
Co-precipitation
Radon emanation,
Radiochemical
Radiochemical
Radiochemical
Fluorometric
Alpha spectrometry
Laser
Phosphorimetry
Radiochemical
Gamma ray
spectrometry
Radiochemical
Gamma ray
spectrometry
Radiochemical
Liquid scintillation
Gamma ray
Spectrometry
Reference (method or page number)
EPA1
900.0
903.1
903.0
904.0
908.0
908.1
901.0
901.1
902.0
901.1
905.0
906.0
901.1
902.0
901.0
EPA2
Pi
p!6
p!3
p24
p4
p6
P9
p29
p34
EPAJ
00-01
00-02
Ra-04
Ra-03
Ra-05
00-07
Sr-04
H-02
EPA4
Pi
p!9
p!9
p33
p92
p92
p65
p87
p92
SMS
302
7110 B
7110 C
7500-Ra C
304, 305,
7500-Ra B
7500-Ra D
7500-U B
7500-U C
(17th Ed.)
7500-U C
(18th or
19th Ed.)
7500-Cs B
7120 (19th
Ed.)
7500-1 B
7500-1 C
7500-1 D
7120 (19th
Ed.)
303
7500-Sr B
306
7500-3H B
7120 (19th
Ed.)
7500-Cs B
7500-1 B
ASTM5
D 3454-91
D 2460-90
D 2907-91
D 3972-90
D 5174-91
D 2459-72
D 3649-91
D 3649-91
D 4785-88
D 4107-91
D 3649-91
D 4785-88
USGS7
R-l 120-76 . .
R-l 141-76
R-l 140-76
R-1142-76
R-l 180-76
R-l 181-76
R-l 182-76
R-ll 11-76
R-l 110-76
R-l 160-76
R-l 171-76
R-l 110-76
DOE"
Ra-05
U-04 . .
U-02 . .
4.5.2.3
4.5.2.3
Sr-01
Sr-02
4.5.2.3
Other
N.Y.9
N.Y.'
N. J.'°
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The procedures shall be done in accordance with the documents listed below. The incorporation by reference
of the following documents was approved by the Director of the Federal Register in accordance with 5
U.S.C. 552(a) and 1 CFR part 51. Copies of the documents may be obtained from the sources listed below.
Information regarding obtaining these documents can be obtained from the Safe Drinking Water Hotline at
800-426-4791. Documents may be inspected at EPA's Drinking Water Docket, 401 M Street, SW.,
Washington, DC 20460 (Telephone: 202-260-3027); or at the Office of Federal Register, 800 North Capitol
Street, NW., Suite 700, Washington, DC.
1. "Prescribed Procedures for Measurement of Radioactivity in Drinking Water", EPA 600/4-80-032 ,
August 1980. Available at U.S. Department of Commerce, National Technical Information Service
(NTIS), 5285 Port Royal Road, Springfield, VA 22161 (Telephone 800-553-6847) , PB 80-224744.
2. "Interim Radiochemical Methodology for Drinking Water", EPA 600/4-75-008(revised), March 1976
Available at NTIS, ibid. PB 253258.
3. "Radiochemistry Procedures Manual", EPA 520/5-84-006, December 1987. Available at NTIS ibid
PB 84-215581.
4. "Radiochemical Analytical Procedures for Analysis of Environmental Samples", March 1979.
Available at NTIS, ibid. EMSL- LV 053917.
5. "Standard Methods for the Examination of Water and Wastewater", 13th, 17th, 18th, 19th Editions,
1971, 1989, 1992, 1995. Available at American Public Health Association, 1015 Fifteenth Street
N.W., Washington, D.C. 20005 . All methods are in the 17th, 18th and 19th editions except 7500-U
C Fluorometric Uranium was discontinued after the 17th Edition, 7120 Gamma Emitters is only in the
19th Edition, and 302, 303, 304, 305 and 306 are only in the 13th Edition.
6. Annual Book of ASTM Standards. Vol. 11.02, 1994. Available at American Society for Testing and
Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428.
7. "Methods for Determination of Radioactive Substances hi Water and Fluvial Sediments", Chapter A5
in Book 5 of Techniques of Water-Resources Investigations of the United States Geological Survey.
1977. Available at U.S. Geological Survey (USGS) Information Services, Box 25286, Federal Center
Denver, CO 80225-0425.
8. "EML Procedures Manual", 27th Edition, Volume 1, 1990. Available at the Environmental
Measurements Laboratory, U.S. Department of Energy (DOE), 376 Hudson Street, New York NY
10014-3621.
9. "Determination of Ra-226 and Ra-228 (Ra-02)", January 1980, Revised June 1982. Available at
Radiological Sciences Institute Center for Laboratories and Research, New York State Department of
Health, Empire State Plaza, Albany, NY 12201.
10. "Determination of Radium 228 in Drinking Water", August 1980. Available at State of New Jersey,
Department of Environmental Protection, Division of Environmental Quality, Bureau of Radiation and
Inorganic Analytical Services, Trenton, NJ 08625.
11. Natural uranium and thorium-230 are approved as gross alpha calibration standards for gross alpha with
co-precipitation and evaporation methods; americium-241 is approved with co-precipitation methods.
12. If uranium (U) is determined by mass, a 0.67 pCi/^g of uranium conversion factor must be used. This
conservative factor is based on the 1:1 activity ratio of U-234 to U-238 that is characteristic of naturally
occurring uranium.
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Streamlining The Method
Approval Process
On March 28th, the first of two proposals
that would radically change procedures
for approving analytical methods for
compliance monitoring under the SDWA and the
CWA was published hi the Federal Register.
This proposal, which was developed by the
drinking and wastewater programs and is called
Streamlining, would allow immediate use of
modifications to current compliance methods,
and adopt a performance-based approach to
approving new technologies for compliance
monitoring. The proposal describes standardized
QC procedures, method validation steps and
acceptance criteria required to obtain approval of
a new or modified method. It would reduce the
need for Agency review of Alternate Test
Procedures because 95 % of the caseload now
involves review of method modifications. It
would also eliminate the urgency to update the
tables of approved methods in the Code of
Federal Regulations when new versions of
methods are published by EPA or organizations,
such as AOAC, ASTM and Standard Methods.
Streamlining specifies performance/acceptance
criteria for inorganic chemicals. Later in 1997,
a second proposal will propose performance
criteria for chemicals not covered in the March
proposal. U.S.EPA may also propose to extend
this process to biological methods.
A final rule is planned for 1998. It would be a
first step towards a performance-based approach
to environmental measurements. The Office of
Water (OW) approach differs from a
performance-based methods system (PBMS) only
in the way it handles approval of new methods.
Under PBMS any method that meets the
performance criteria for an analyte could be used
for compliance monitoring without notifying the
Agency. OW would allow modified compliance
methods to be used without notification;
however, new methods or technologies would
continue to require formal Agency review
because the QC procedures and acceptance
criteria specified in regulations for that analyte
may have to be adapted to the characteristics of
the new technology. Because EPA's streamlined
methods approval process would provide a
quicker, more standardized review of new
technologies than hi the past, method developers
should not strongly object to letting a regulatory
agency "look under the hood" prior to using a
new method for compliance monitoring.
The public comment period on this rule has been
extended so that EPA can take public comment
in Dallas at the end of the NELAC meeting on
August 1st from 9:00 AM until 1:00 PM.
Another earlier public meeting will be held in
Chicago on July 17 from 9:00 AM until 12:30
PM. Registration will begin at 8:00 AM for
both meetings. To receive information on these
meetings, contact Ms. Cindy Sambanin at 300
North Lee Street, Suite 500, Alexandria, VA
22314-2695 (fax 703 684-0610). The March
28th Federal Register and the support documents
that are a part of the administrative record for
the Streamlining proposal may be downloaded
hi WordPerfect or .pdf format from the Office of
Water home page. The URL is http://earthl.
epa.gov/OW/. Look under the April 10th entry
of "What's New". The support documents, but
not the Federal Register text, are also available
in print or on 3.5-inch disks from several
sources: NCEPI (513 489-8190), NTIS (703
487-4650) or ERIC (800 276-0462). The titles
and the NCEPI, NTIS and ERIC order numbers
are: Guide to Method Flexibility and Approval
of EPA Water Methods (the Streamlining
Guide) EPA-821-D-96-004, NTIS PB97-117766,
ERIC D-A43 or ERIC D-A46 (diskette) and
-------
Guidelines and Format for Methods to Be
Proposed at 40 CFR Pan 136 or Part 141, July
1996, EPA-821-B-96-003, NTIS PB96-210448,
ERIC D-A42 or ERIC D-A45 (diskette). For
further information you may contact Richard
Reding by FAX 513 569-7191 or e-mail reding.
richard@epamail.epa.gov.
Cofflert-18® Method For
Coliforms And E.coli
Colilert-18® is an optimized formulation
of Colilert for the detection of total
coliforms and Escherichia colt that
provides results within 18 hours of incubation at
35C rather than the 24 hours required for
Colilert®. The Colilert-18® method was
evaluated by the manufacturer by comparing it to
the Colilert® procedure and it was found to give
statistically higher results for both coliforms and
E.coli. In September 1996, OGWDW approved
Colilert-18® to determine the presence or
absence of total coliforms and E.coli hi drinking
water under the TCR (40 CFR 141.21) and to
enumerate total coliforms in source water under
the SWTR (40 CFR 141.74).
Quanti-Tray® Methods
For Total Coliforms And
E.coli
In 1990, EPA approved the MMO-MUG Test
(Colilert®) for the detection of total
coliforms and E.coli under the Total
Coliform Rule. More recently, IDEXX
Laboratories, Inc., the manufacturer of
Colilert®, developed the Quanti-Tray® and
Quanti-Tray 2000® Tests. The Quanti-Tray® test
is performed by adding a water sample to the
commercially available Colilert® medium and
then distributing this mixture into a plastic
packet containing 51- two mL wells. The
Quanti-Tray 2000® test follows the same
procedure using a packet containing 2000 small
wells. The packet is incubated for 24 hours at
35C and then examined for a color change and
fluorescence hi the wells to determine presence
or absence of total coliforms and E.coli.
Alternatively, Most Probable Number tables
provided with the tests may be used to enumerate
these organisms.
In 1996, the Office of Ground Water and
Drinking Water (OGWDW) and the Office of
Research and Development evaluated the product
literature for the Quanti-Tray® tests for detecting
total coliforms and E.coli under the Total
Coliform Rule and enumerating total coliforms
under the Surface Water Treatment Rule. Based
upon this review, OGWDW has determined that
no additional approval is needed. The Quanti-
Tray® tests use a 100 mL water sample as
required by the Total Coliform Rule and the
Colilert® formulation is the same as that already
approved by EPA. Therefore, laboratories may
use the Quanti-Tray® tests to determine the
presence or absence of total coliforms and E.
coli in drinking water under the Total Coliform
Rule (40 CFR 141.21), and enumerate total
coliforms in source waters under the Surface
Water Treatment Rule (40 CFR 141.74). For
more information contact Bob Bordner 513 569-
7932.
New Test For Total
Coliforms And E.coli
A
I new membrane filter (MF) test for the
simultaneous detection and enumeration
of total coliforms (TC) and E.coli in
-------
water has been developed by the National
Exposure Research Laboratory, U.S. EPA,
Cincinnati, Ohio. The test is based on the
specific enzyme activities of these organisms and
uses MI agar medium. This medium contains a
fluorogen, 4-methylumbelliferyl-p-D galactopy-
ranoside, that produces a bright fluorescence
when cleaved by total coliforms, and a
chromogen, indoxyl-p-D-glucuronide, that forms
a blue color when cleaved by E.coli. In
developmental studies, recoveries of TC and E.
coli on the new medium were compared with
those of mEndo agar for TC and two E.coli
media, mTEC agar and nutrient agar
supplemented with MUG (NA+MUG), using
raw water samples and spiked drinking water
samples. The current EPA-approved MF
method for E.coli requires growth on mEndo,
MF transfer to NA+MUG, and an additional
four hour incubation (mEndo-NA+MUG). MI
recovered significantly higher numbers of TC
with greatly reduced background non-coliform
counts. The new medium also recovered more E.
coli than mTEC hi 16 of the 23 samples, but the
differences were not statistically significant.
Both MI agar and mTEC agar recovered
significantly more E.coli than NA+MUG.
Specificities for E. coli and TC on MI agar were
95.7% and 93.1%, respectively. The E.coli
false-positive and false-negative rates were both
4.3%. This selective and specific medium,
which employs familiar MF technology to
analyze several types of water, provides results
in 16-24 hours at 35C, is less expensive than
liquid chromogen and fluorogen media (e.g.,
Colilert® and Colisure®), and eliminates the need
for repeat samples, serial analyses, and MF
transfers.
A single-laboratory study using tap water
samples spiked with various waste waters
showed MI to be superior to mEndo-NA+MUG
in recovery of both target organisms, reduction
of background organisms, and the ability to
recover chlorine-damaged target organisms hi
drinking water. In this study, the source water
and water treatment types, the geographical
origin of the wastewater, and the different
wastewater sources did not adversely affect the
performance of the new method.
An inter laboratory evaluation involving 19
geographically dispersed laboratories, compared
the new method to the U.S. EPA approved
method using six wastewater-spiked drinking
waters. The study showed that although the
overall recoveries of TC and E.coli with MI agar
were 12% and 26% greater, respectively, than
those of the approved method, the differences
were not statistically significant. However, the
overall recovery of non-coliforms by the new
method was significantly lower. Because the
results of this study show MI agar to be equal to
or better than the current method, it meets the
criteria for routine compliance monitoring of
drinking water. The MI method has been
submitted to the Office of Ground Water and
Drinking Water for approval consideration.
Questions or comments may be directed to the
editors or Dr. Kristen Brenner, National
Exposure Research Center, 513 569-7317.
Analysts are advised to compare this method
with other methods before adoption. Be aware
that this method has not yet been approved for
compliance monitoring.
The following references will offer additional
information:
Brenner, K.P. et. al., 1993. New Medium
for the Simultaneous Detection of Total
Coliforms and Escherichia coli in Water.
Appl. Environ. MicrobioL 59:3534-3544.
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Brenner, K.P. et al., 1996. Comparison of
the Recoveries of Escherichia coli and Total
ColifQrmsJrom Drinking Water by the MI
A gar Method and the U.S. Environmental
Protection Agency-Approved Membrane
Filter Method. Appl. and Environ.
Microbiol. 62:203-208
Brenner, K.P. etal., 1996. Intel-laboratory
Evaluation of MI Agar and the U.S.
Environmental Protection Agency-Approved
Membrane Filter Method for the Recovery
of-Total Coliforms and Escherichia coli from
Drinking Water. Jour. Microbiol. Methods
27:111-119
Colisure® Test for Total
Coliforms and E.coli
Millipore Corporation, the manufacturer
of Colisure®, has notified EPA that a
change in the manufacturing process
of the Colisure® medium has resulted in a
granulated product which is visibly different from
the original powder version. The formulation of
granulated Colisure® is the same as that approved
for drinking water and surface water monitoring in
January 1995, and is still subjected to the same
stringent quality control and performance
specifications by the manufacturer. The new
version is provided in a smaller bottle which
allows users the option of their own reusable
culture vessels, reduces solid waste from extra
packaging, and requires minimum storage area.
The Office of Ground Water and Drinking Water
has determined that no additional approval is
necessary
Handbook on
Cryptosporidium and
Water
The Working Group on Waterborne
Cryptosporidiosis has developed a
publication, Cryptosporidium and Water:
A Public Health Handbook - 1997, to help state
and local health departments and water utilities
prepare for and respond to reports of
Cryptosporidium in drinking water and source
waters. The Working Group is composed of
representatives from the U.S. EPA, National
Centers for Disease Control and Prevention
(CDC), other interested federal agencies, state and
local health departments, the drinking water
industry, and organizations representing the
concerns of immunocompromised persons. The
publication of the Handbook is particularly timely
as federally mandated water monitoring goes into
effect in 1997 under the Information Collection
Rule. The occurrence of Cryptosporidium in
drinking water sources throughout the nation and
the need for more reliable methods to determine if
sufficient viable oocysts are present to cause an
outbreak, combine to create a monitoring
challenge.
The objectives of the Handbook are to provide
tools for prevention and investigation of
Cryptosporidium and other pathogen outbreaks.
Prevention techniques include review of source
water protection programs, optimization of water
treatment methods, development of a task force to
determine a system's vulnerability to
Cryptosporidium, preparation of risk assessment
protocols, and contingency plans for reports of
microbial contaminants, such as issuing or
rescinding boil water orders. Guidance for
outbreak investigations includes careful
interpretation of water testing results, assessment
-------
and development of health department
capabilities for outbreak detection, initiation of
epidemiological studies to detect outbreak
occurrence, and development and coordination of
emergency response teams.
Emphasis is placed on public response to reports
of Cryptosppridium or other pathogens in
drinking water supplies. Guidance is included on
providing informational materials on microbial
contaminants and maintaining a good working
relationship between water systems, the media
and the public. Emergency telephone numbers are
listed for state health departments, U.S. EPA, and
CDC. Special informational materials for
immunosuppressed persons are also provided.
Copies of the Handbook can be obtained by local
health departments from their respective state
health departments. Members of the drinking
water industry may order the document from the
American Water Works Association at 800 926-
7337. The cost is $20.00 for members, $30.00 for
non-members.
Regarding Cyanide
There are interferences in the electrode
method for cyanide. Probably the most
severe is sulfide. If sulfide is present
there will be a positive interference when
measuring cyanide.. If sodium thiosulfate is
being used to dechlorinate, it might form sulfite
and interfere. The use of ascorbic acid may
alleviate the problem. If a compliance sample
exhibits an interference and the sample was not
chlorinated or ascorbic acid does not help, then
there is a serious problem and distillation may be
required. When a sample is distilled the value
obtained with the electrode is actually a "total"
value. In this case, the only way a free value
could be obtained would be to resample'and use
the "Amenable" method.
We have had questions regarding false positive
values being obtained on the last PE sample
(WS038) for CN. These PEs were made using
potassium ferricyanide and therefore should not
give a free value. However, they were old and if
exposed to light might have broken down and
formed some free cyanide. The next PE will be
produced specifically as free CN, so this should
not occur.
Update On The Ground
Water Disinfection Rule
The Safe Drinking Water Act (SDWA)
amendments of 1986 directed the
U.S.EPA to develop requirements for
disinfection of drinking water to prevent
waterborne disease and reduce endemic illnesses.
In response, the Surface Water Treatment Rule,
promulgated hi 1989, requires disinfection and
further treatment, where appropriate, of drinking
water from surface sources and ground water
under the direct influence of surface water. The
Total Coliform Rule, promulgated at the same
tune, set maximum contaminant levels for
coliform bacteria, listed the analytical methods
for monitoring finished and source waters, and
established enforcement actions. The 1996
SDWA amendments specifically directed the
Agency to issue regulations requiring
disinfection "as necessary" for ground water
systems. The Ground Water Disinfection Rule
(GWDR) under development will complement
the two earlier regulations to improve the
microbial quality of drinking water, but will
apply a different approach for ground water
systems because of the various kinds of source
waters, types and degrees of treatment currently
-------
in use, and economic considerations for small
systems.
Ground Water Microbial Problems
Information is not complete on the magnitude
and significance of the national public health
problems from microbial contamination of
ground water systems. However, epidemiologi-
cal reports indicate that about half of all known
waterborne disease outbreaks occur in ground
water systems. The actual number of outbreaks
may be significantly higher because of
substantial under reporting. EPA risk assess-
ments estimate that four to five million illnesses
per year could be attributed to consumption of
public ground water supplies.
The 44,000 smaller community and 120,000
noncommunity systems that rely mostly on
ground water may have little or no treatment in
place, often have no distribution system at all,
and typically have limited financial resources.
U.S.EPA's Safe Drinking Water Information
System shows that more than 85 percent of the
acute microbial Total Coliform Rule violations of
community systems come from systems using
ground water. According to reports on ground
water disinfection and protective practices hi the
United States, only about 55 percent of
community systems have some form of
disinfection in place.
Development of the GWDR
GWDR discussions have included representatives
from U.S.EPA, states, utilities and other
interested parties. They have identified major
problems, considered appropriate public health
goals, and suggested a multiple barrier approach
to ensure groundwater safety. The regulatory
goals of the GWDR are: 1) to prevent fecal
contamination rather than to attack it after it
occurs; 2) to emphasize treatment and
operational requirements rather than setting
maximum contaminant levels for specific
microorganisms; 3) to focus on overall
management procedures rather than treatment
alone; and 4) to use credible science and best
available technology.
The multi-barrier approach that the work group
has under consideration includes the following
concepts:
o Groundwater Source Protection: For systems
not disinfecting, an assessment of the adequacy
of a natural barrier to fecal contamination
reaching the wellhead may be required. Non-
disinfecting systems would have to eliminate or
control sources of contamination or ensure that
adequate natural disinfection is occurring in the
ground. If the source water is shown to be
contaminated, correction or treatment and
adequate monitoring would be required. If the
aquifer is sufficiently protected, no wellhead
disinfection may be necessary.
o Sanitary Surveys: Sanitary surveys and
correction of defects may be required on a
periodic basis to establish a contamination
barrier based on well and distribution system
integrity. If the surveys indicate protection is
inadequate and correction is not completed,
disinfection would be required. If they show
that reasonable barriers are in place to prevent
contamination, disinfection may not be required.
o Distribution Systems: For systems not
disinfecting, adequate operation and maintenance
procedures such as pressure maintenance, cross
connection control, backflow prevention,
flushing and low heterotropic bacteria counts
could be required. It may be necessary to
require groundwater systems to maintain
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disinfection residual, unless they meet criteria
ensuring equivalent protection.
o Disinfection Treatment: Disinfection would be
required of all systems with uncorrected fecal
contamination. EPA may provide flexibility by
allowing degrees of disinfection or options to
chlorination such as ultraviolet light, ozonation
or ultrafiltration, particularly for small systems.
Disinfection can provide a barrier at any or all
points in the system.
o Monitoring Requirements: For systems not
disinfecting, some monitoring of the source
water for viruses and bacteria is likely to be
required as part of the vulnerability assessment.
Systems that have sources vulnerable to fecal
contamination and no treatment would likely be
required to perform regular source water
monitoring. Those with less vulnerable sources
might need limited source water monitoring
requirements.
Ongoing Development
The GWDR is in the preproposal stage of
development. The workgroup is developing
additional regulatory requirements with attention
to economic impact, cost and benefit analyses,
and affects on small businesses. It is recognized
that GWDR requirements must be consistent
with other disinfection regulations, feasible for
the states to implement, and practical and
affordable for the systems. Current plans are to
propose a regulation in late 1998 and promulgate
a final rule in 2001.
For a detailed account of the GWDR
development and status, see "Update on the
Ground Water Disinfection Rule", B. A. Macler
and F. W. Pontius, Journal of the American
Water Works Association, January 1997.
Errata
The August '95 Labcert Bulletin contaminant
table contained the following errors:
1) Sodium has a recommended level not a MCL.
The footnote in the MCL column should have
read "9".
2) The acceptance limit for Vinyl Chloride is ±
40% not + 20/40%.
3) The acceptance limit for Antimony is ± 30%
not +15 % as listed.
If you don't have this very useful edition, write
or call the editors for a copy.
Web Sites Of
Interest
If you have access to the
Internet, some interesting
sites are listed below.
URL http://www.epa.gov
1) /ORD/whatsnew.htm
ORD has a site in "What's New" and lists the
NERL manual of manuals.
2)/OGWDW/labindex
At this site, OGWDW has the Fourth Edition of
the Manual for the Certification of Laboratories
Analyzing Drinking Water. This bulletin, as well
as many other interesting things, can be found on
the OGWDW home page.
3) /ICRsom.htmI
This site contains information about the ICR.
4)/SDWAhotline
Access to the SDWA Hotline.
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EPA Microbiology Home
Page
March 1997 marked the first full year of operation
of the EPA Microbiology Home Page on the
World Wide Web. This public Internet website
was developed from the EPA Microbiology
Gopher which was operational on the Internet
from January 1994 to November 1995. Since
March 1996, the website has been accessed by
individuals in over 67 different countries and
transferred almost 7 gigabytes of information.
The website was established to provide public
access to microbiology-related information that
has been developed or managed by the Agency.
The website is maintained by the Human
Exposure Research Division, NERL-Cincinnati,
located at the Andrew W. Breidenbach
Environmental Research Center, a focal point for
microbiological research in ORD.
Among the publications available for viewing and
downloading are documents relating to the
Information Collection Requirements (ICR) rule.
Online publications include: the U.S.EPA Manual
of Methods for Virology (12 chapters), the ICR
Microbial Laboratory Manual (233 pages), a table
of Cryptosporidium antibodies, various ICR
microbiology guides, and an overview focusing
on EPA's microbiology-related research. ICR
related software is also available at this site.
There is also a publication list (by year) of EPA-
supported research in environmental
microbiology. The list includes research
conducted by EPA scientists and research
conducted through EPA grants and cooperative
agreements. Visitors to this site can also view a
brief video clip on virus cultivation, as well as a
number of images of viruses and protozoans
obtained using electron microscopy and confocal
microscopy. The site can be assessed via web
browser at the following URL:http://www.epa.
gov/microbes/.
Contact: Fred Williams 513 569-7388, Human
Exposure Research Division, Cincinnati
United States
Environmental Protection Agency
Office of Ground Water and Drinking Water
Cincinnati, OH 45268
Official Business
Penalty for Private Use
$300
EPA-815-M-97-002
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No G-35
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