United States
                   Environmental Protection
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.
   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


        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
    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

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

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

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

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.

                          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
Approved Methods for Radionuclide Contaminants
Naturally occurring
Gross alpha" and beta
Gross alpha"
Radium 226
Radium 228
Radioactive cesium
Radioactive iodine
Radioactive Strontium
89, 90
Gamma emitters

Radon emanation,
Alpha spectrometry

Gamma ray
Gamma ray
Liquid scintillation
Gamma ray
Reference (method or page number)
















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
7500-1 B
7500-1 C
7500-1 D
7120 (19th
7500-Sr B
7500-3H B
7120 (19th
7500-Cs B
7500-1 B

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

R-l 120-76 . .

R-l 141-76
R-l 140-76

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


U-04 . .
U-02 . .

N. J.'°

 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
 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.

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.

 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


    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-

New Test For Total

Coliforms And E.coli
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

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

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.

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

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
Handbook on

Cryptosporidium  and


       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

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
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

 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

 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

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

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.

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


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.

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.

Access to the SDWA Hotline.

EPA Microbiology Home


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.

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

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