PROTOCOL FOR NATIONWIDE APPROVAL OF NEW OR REVISED
METHODS FOR INORGANIC AND ORGANIC ANALYTES IN NATIONAL
     PRIMARY DRINKING RATER REGULATIONS MONITORING
                     Revision 1.5

                     January/ 1996
         U.S. Environmental  Protection Agency
          Office of Research and Development
         National Exposure Research Laboratory
                Cincinnati/ Ohio  45268

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             PROTOCOL FOR APPROVAL OF MEW OR REVISED
     METHODS  FOR INORGANIC AND ORGANIC ANALYTES IN NATIONAL
          PRIMARY DRINKING RATER REGULATIONS MONITORING
INTRODUCTION

    The Administrator/  U.S. Environmental Protection Agency  (EPA),
approves analytical methods  for all contaminants regulated under
the  Safe  Drinking Water  Act   (SDWA) .    When  EPA publishes  a
regulation under the SDWA  that  sets a maximum contaminant level,
the  regulation generally  provides for  at least  one analytical
method  for detection and/or quantification  of that contaminant.
After any  regulation  is published/  EPA may  approve additional
methods  or  modification to currently approved methods/ following  a
set chemical method or microbiological method protocol of the  ATP
program.

    This protocol describes the information and data EPA needs to
evaluate an ATP for  CHEMISTRY.   The protocol is flexible in that
EPA's National Exposure Research Laboratory  (NERL) may tailor  the
criteria to  a particular analyte, method/  and/or sample matrix.
For  this  reason/  before  beginning  the  required  testing,   the
applicant is  encouraged to discuss the application with EPA/NERL  -
Cincinnati/  26 West Martin  Luther King Drive,  Cincinnati/  Ohio
45268, to assure agreement on the testing design.

    If the data evaluation  demonstrates that the applicant's method
performs at  least  as well as the  currently approved method,  EPA
will  recommend its approval  to the  Office of  Ground  Water  and
Drinking Water, which  begins the regulation development process.
Regulation  development  includes a Federal Register notice proposing
to  approve an ATP/  public comment  on  the proposed method/   and
(depending  on public  comment) a final rule published in the Federal
Register approving the method. The regulation development process
may take about one year or more.

APPLICATION REQUIREMENTS

      Any person may apply for  nationwide  approval of the use of
either  a  new method  or  an optional  minor  modification of  a
previously promulgated method for a specific constituent in NPDWR
monitoring.    Before  submitting  an application/   however/   the
applicant must provide  a detailed write-up of the proposed method.
If  the   proposed  method  is  very  similar  to  an  approved   and
promulgated method/ and/or represents a minor optional change of an
approved method/ the applicant should simply prepare a two-column
side-by-side listing of the sections of the approved and proposed

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methods.   This  document should include the title/ identification
number and date of  each  method and  all  the topics  in the EMMC
format provided in the Section, Method Description Requirements
beginning  on page  2  of  this  document.    The  applicant  should
highlight  differences  between  the. proposed and approved methods.
If the method is an  automation of a  previously approved  manual
method,  any differences in kinetics  and  interferences should be
presented and a  comparison of the final ratios of the reactants in
the  proposed and  approved  methods  should be  included.   This
information should then be forwarded to NERL-Cincinnati  for review.
NERL-Cincinnati will recommend nationwide approval/disapproval of
the proposed method as:  1) identical to EPA's reference method, 2)
an optional minor modification of a previously promulgated  method
or 3) significantly different method requiring an application for
an ATP as  a new or revised method.

    Every application  for approval  of a new method or optional
minor modification of a previously promulgated method  shall be made
by letter  in triplicate and forwarded  to the Director,  Ecological
Exposure  Research  Division -  Cincinnati  (NERL-Cincinnati), U.S.
Environmental Protection Agency, Cincinnati, Ohio 45268.

    The  general requirements  for  an  application  for  nationwide
approval  of   any new  or modified method  include  the name and
address  of the  applicant and/or authorized representative; the
contaminant  for  which the new  or modified procedure is proposed;
justification for the proposed new or modified method;  the title of
the method, company identification number and date of  preparation
of the proposed  method;  and, a complete description of the proposed
method and of the  approved method if  used  in a comparison.  All
information  provided  to  the  Government  is  subject  to  the
requirements  of  the  Freedom of Information Act.  Any  proprietary
information   in  the   proposed  method  should  be  marked  as
"Confidential".     USEPA  staff  will  handle   all   proprietary
information  according to  the regulations in  subparts  A and B of
Part 2 of  Title 40 CFR.

     Initially,  an applicant should forward  the above information,
except the comparability data, to NERL-Cincinnati.  Upon receipt of
the  application,  the NERL-Cincinnati  staff  will  assign  an
identification number for  the application, which should be used in
'all  future communications.   The NERL-Cincinnati  staff will also
evaluate the submitted information and  advise the applicant  of the
specific comparability  data requirements, if applicable.

Method Description Requirements

    The  method  write-up must address the following  topics  listed
in  the recently  formulated Environmental  Monitoring Management

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Council (EMMC) method format:1

1.0 Scope and Application

    Include analyte identification; CAS number; sample type;  method
    sensitivity/ expressed as mass; and/ concentration  range.

    The range of the proposed method should be equal  to  or greater
    than that of the approved method.  If the range is smaller than
    that  of the approved method  (particularly/  if  the detection
    limit is  larger), NERL-Cincinnati may advise that  the  method
    is  inapplicable or the method may require  a declaration of
    method  limitations.

2.0 Summary of Method

    Describe   scientific  basis/   e.g./    chemical  principles/
    reactions/ and  kinetics.

3.0 Definitions

4.0 Interferences

    As  a  separate  document/  include data  observed by applicant
    (during method  development)  using typical samples  containing
    a specific quantity of an interfering substance).

5.0 Safety

    Refer to good laboratory practice/ appropriate material  safety
    data  sheets/  and use  of  a hood/  goggles/  and/or  protective
    clothing.  Emphasize any special procedure.

6.0 Equipment and Supplies

    As separate documents/ include applicable manuals.

7.0 Reagents and Standards

    Describe  reagent  formulations  and shelf life of packaged
materials.
/
8.0 Collection, Preservation/ Shipment/ and Storage

    See general guidance in laboratory certification manual2.

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9.0 Quality Control (QC)

    Indicate need for a  formal laboratory quality assurance/quality
    control  program;   initial   and   periodic  documentation  of
    performance by reporting results of analyses of  reagent blanks/
    check standards, and/or fortified samples; and,  maintenance of
    records, QC charts,  etc.  The periodic checking of performance
    should  preferably occur at  a minimum frequency of 10% of the
    total samples.

10.0 Calibration and Standardization

    This section should  include the calibration steps that are not
    performed daily.  Include the daily calibration step(s) in the
    procedural section.

11.0 Procedure

    Include  in the method write up the  procedural steps and the
    daily calibration steps.   As  a  separate  document  include a
    typical calibration graph or curve.

12.0 Data Analysis and Calculations

13.0 Method Performance

    Indicate  the percent  recovery,  precision,  and bias of the
    method  for typical  samples,  fortified with a known amount(s)
    of the  analyte.   Include the method detection limits (MDL),
    derived  as outlined in Appendix B of section 136 of Title 40
    of CFR,  and  expressed in weight/volume.   The  calculated MDL
    should  be  confirmed by analyzing  a samples at  the calculated
    MDL concentration.  Note  that  the MDL should  be equal  to or
    smaller  than that  of  the approved  method.   If the MDL is
    larger,  NERL-Cincinnati  may  advise  that  the  method  is
    inapplicable  or the method may require  a  declaration of the
    limited range of performance of the method.

14.0 Pollution Prevention

    Cite good laboratory practices for pollution prevention.

15.0 Waste Management

    Cite how waste and samples are to be disposed.

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16.0 References

     Include  reference to documents  and publications.

17.0 Tables/ Diagrams/ Flowcharts,  and Validation Data

    Any  proprietary information in the proposed  method should be
marked  "Confidential".  USEPA  staff  will handle  all  proprietary
information  according to the regulations  in subparts A  and  B of
Part 2 of Title  40  of CFR.

Comparability  Data  Requirements

     A method comparability  study will  be  required for each new or
significantly  revised method submitted for nationwide approval.
Guidance for the comparability  study  is provided  in the following
text.  Applicants are encouraged to  have a brief consultation with
the  NERL-Cincinnati  ATP staff  regarding specific  comparability
study plans which may include the number of analyses, concentration
levels/  quality control  (QC)  activities/ performance evaluation
 (PE) samples/ etc.  If a  major area  such as the concentration range
of the proposed method differs from that of the  approved method/
the  applicant  must consult with the NERL-Cincinnati ATP staff to
determine the  appropriate modification of the  comparability study
design.  The required comparability  data shall include measurements
of drinking  water samples/  QC samples  and PE samples.   Initially/
each collected drinking water will be analyzed at least once by the
approved method to determine the concentration  of  the constituents
of  interest and need for  sample   dilution  and/or  fortifying to
achieve  the 5  x MDL  baseline  concentration  as  detailed  in the
Subsample Preparation Requirements (pp.  6-7).  After appropriate
preparation/ the subsamples  of each  drinking water will be analyzed
by both  the  approved and proposed methods.

     The  QC samples and the PE samples  are  to  be  prepared in reagent
water  and used to determine if  the laboratory  is in control.  PE
samples  of   known  analytes/  but of concentration unknown  to the
analyst/  will   be  provided   by  NERL-Cincinnati   along  with
instructions for use.  The analyst is responsible for preparing the
/final  QC and  PE sample solutions  for analyses.    The QC  and PE
solutions must be  spaced every tenth  sample  among the drinking
water samples  which are  to  be analyzed by both methods.

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    As general  guidance,  the minimum number of analyses  required
are summarized in the following table.  However, depending  on  the
particulars of the method under review, the number of  analyses  may
change.   We strongly suggest consultation with the NERL-Cincinnati
ATP staff prior to analyses.
Approval
type
Applicant
Drinking water sample or
subsample analyses per
regulated constituent
QC\PE
Samples
Total
                     Initial  Adjusted  Forti-
                     screen   to 5 MDL   fied

Nationwide  Any      10         60      120-180    22-25   212-275
Drinking Water Sampling Requirements

    For each  constituent  of interest,  the applicant must  collect
a  minimum of ten  drinking water  samples,  ideally  one from  ten
geographically-dispersed  drinking water  supplies.  Six of  these
supplies should  be  from surface water sources and four  from ground
water sources.  The supplies should contain variable  water  quality
characteristics  that may  affect  the analyses.   These  include  pH,
TOC, alkalinity,  and TOX. We strongly suggest consultation with  the
NERL-Cincinnati ATP staff prior to sampling.

    An applicant is required to diligently select  a  source and/or
time  of  collection that will afford  an analyte concentration as
close as  possible  to   5 times the  published MDL of the approved
method. (If the  MDL is  unpublished, determine as directed in topic
13 on pp. 4).   This sample selection will enable  the  preparation
of the required  subsamples by either dilution or fortifying with a
minimum of alteration  of sample matrix.

    Most  samples   should  be  collected  using  the  containers,
preservation techniques, and holding times outlined  in the approved
methods.    Samples  for  asbestos,  barium,  cadmium,   chromium,
fluoride, mercury, nitrate, nitrite, and selenium  analyses should
be handled as outlined in the Phase II  regulations2.

Subsample Preparation  Requirements

    The bias, precision, percent recovery and MDL  of the proposed
method will be compared to those of the approved method.   Several
levels of concentrations covering  the performance  range   of  the

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proposed method will be used in the study.  Ideally, the range  of
the concentrations  for the proposed method will be the same  as the
approved method.  The concentrations should include a level that  is
5 X MDL, a  level that  is twice the maximum contaminant level and
additional  levels  that take into account  the method range. This
issue must be addressed with the NERL-Cincinnati ATP  staff prior  to
analyses.

    The  study experimental  design  initially requires  a  single
analysis of  each of the collected samples by the approved method  to
determine the concentration of the  constituents  of interest.   If
the initial concentration of constituents in  any collected  sample
differs significantly from the 5 x MDL level,  the sample must then
be  either  diluted or  fortified  to achieve  the  5 x  MDL  level.
Dilution must  be   done using  deionized distilled water.    Sample
fortifying must be accomplished using a substance whose character
reflects the nature of the analyte in the drinking water and/or the
calibration  standards.  For example/  in an application for mercury,
the  fortifying  substance  should  consist  of  a mixture  of   an
inorganic and  an  organic mercury compound.   All of the initial
dilution  or  fortification  (to  achieve  the desired  5   x  MDL
concentration) must be performed before  splitting  a sample into
subsamples.   Otherwise, the analytical error  of each analysis may
also include the error of the individual dilution or fortification
of  the  subsamples  and the data  comparison may be  inappropriate.
Record and  report  the  initial  dilution or fortifying required  to
adjust each sample concentration to the 5 x MDL level.

      The fortification of each  subs ample  must also be performed
before aliquoting  for  analysis.   Otherwise,  the analytical error
will include any individual fortification error and  the comparison
data may be inappropriate.   Record and report the amounts  of the
substance added  to each fortified  subsample  and  the theoretical
total concentration in each subsample.   The  latter is calculated
for subsample by adding the mean of  the triplicate analyses  of the
subsample by the approved method to the amount of substance added
to  that  subsample.  The  evaluation of the comparability of the
proposed method  is dependent upon  the  analyst's  preparation and
analysis   of  corresponding   subsamples  with    very   similar
concentration.

Laboratory Requirements

    It is highly desirable  to have one laboratory analyze  all  of
the samples  required in the study design.   This is to eliminate the
effects of multiple laboratories on  the comparison of data between
methods.  Analyses by an additional laboratory should be included
as  a QC  check but  these  data  are in addition to the required ATP
comparative  analyses by the primary laboratory. This option  should

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be discussed with  the ATP staff.  Preferably,  the  laboratory should
be independent. NERL-Cincinnati will judge on the appropriateness
of the suggested laboratory.

Approved Method Selection Requirements

    Since the approval of a method'depends upon the comparability
of the  bias and precision  of  the proposed method to  that of an
approved method, the applicants's analyses by the approved method
must also be examined to determine their acceptability as a basis
in  the comparison.   This  acceptability  will  be determined by
evaluating the applicant's  analyses  of QC  and PE samples by both
the approved method and the proposed method.

    The  criteria used  in  the evaluation will  be  derived from
available regulations, text of the approved method, and/or various
interlaboratory  validation  and/or   PE  studies.    USEPA  may,
consequently,  limit the applicant's choice of  an approved method to
insure that the approved method used in the study  is one which has
been  evaluated with  sufficient frequency  in the interlaboratory
studies to afford  an appropriate data base with which to determine
the acceptability of the  applicant's  analyses  by  the approved
method.

Drinking Water Subsample Analysis Requirements

    As  general  guidance, applicants  for nationwide approval of a
new or  significantly  revised method  must perform six analyses of
each  subs ample,  three by  the  approved  method  and three  by the
proposed  method.    The  drinking  water  sample,  drinking  water
subsample,  and  analysis  requirements  are  summarized  in  the
following table:

Approval Applicant No.of    No.of     Total No. No.of   Total No.
                  collected subsamples samples  repli-  of
                  samples      per       for    cate    analyses
                            Collected  analysis analyses
                              Sample            per sub-
                                                sample
                                                per each
                                                of two
                                                methods
Nationwide   Any     10      3-4       30-40          3     180-240


    The aforementioned QC analyses should be performed along with
the analyses  of the drinking water subsamples  (see  Comparability
Data Requirements, p. 5) .

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Data Reporting Requirements

    Initial  single observation  of  each collected  sample by  the
approved method,  the initial dilution  and/or fortifying of  each
collected sample,  the quantity of substance added to  each subsample
and the  total theoretical concentrations  of the subsamples,  the
replicate observations of all subsamples by  both methods, and the
quality  control  observations  must  be  forwarded  to  USEPA.    A
suggested format  for reporting  the  observations of  each set  of
subsamples  is  attached.    The  quality  assurance observations
associated with each set of subsample observations  should also be
tabulated and identified.  An evaluation of the  application can be
accomplished  more  quickly by  the  NERL-Cincinnati  program  and
statistical  staff,  however, if the information is also  forwarded on
a floppy disc compatible with an IBM-PC computer.  The  text on the
disc  should be presented in the latest  version  of  WordPerfect
(currently,  6.0) and the data may be presented in WordPerfect or in
ASCII.

DATA REVIEW AMD METHOD RECOMMENDATION

    Upon  receipt  of the  applicant's data sets, NERL-Cincinnati
staff  will  initiate  its  technical  and   statistical  reviews.
Appropriate  criteria, derived either from published  regulations or
from  interlaboratory  studies,   will  be  used  to  determine   the
acceptability  of   the  approved  method  data as  a  basis  in  the
evaluation  of  the  analyses by  the  proposed  method.   If  this
evaluation is favorable, the evaluation of the comparability of the
proposed method will follow.   (If the results of the  analyses by
the approved method are not satisfactory,  the applicant will  be
notified that the application has been defaulted.)

    Since  the  sampling  and  analytical  requirements  for   each
application for approval of a new or significantly  revised method
are based on a  factorial  experimental design with  three factors,
namely,  method,  sample matrix, and constituent concentration,  each
comparability  review will be conducted over the  range of these
three factors.  Descriptive statistics, such  as  the  mean,  standard
deviation, coefficient of variation (relative standard  deviation),
and percent  recovery of each set of replicates will  be  calculated.
The precision of the proposed method will be  compared with that of
the  approved  method by  means  of  a  nonparametric   statistical
procedure attributable to Scheffe.  An analysis of variance (ANOVA)
will be used to compare  the recovery of the  proposed  method  with
that of the approved method.

    Upon completion of  the technical and statistical reviews, NERL-
Cincinnati will prepare its recommendation for approval/disapproval
of the new or significantly revised method,  notify the  applicant of
its recommendation,  and forward the recommendation to the Office of

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Ground  Water   and  Drinking   Water  (OGWDW),   which   has  the
responsibility  of  proposing the method in  the  Federal Register.
After a three-month public  comment  period,  OGWDW will review any
submitted   comments    and   prepare   the    final   nationwide
approval/disapproval decision and notice in the Federal Register.

    If  you have   any  questions  regarding  the  requirements/
especially  the  comparability study  design and sample fortifying,
please contact the NERL-Cincinnati ATP staff at 513-569-7307.


REFERENCES

1.  Villa,  0.  and L.  Reed, Co-Chairs, EMMC  Methods Integration
    Panel.   Final  Version of Approved EMMC Format  (Memorandum to
    Members of EMMC Steering Committee, Methods Integration Panel
    and Work Group,  Tri-Chairs).   U.S.  Environmental Protection
    Agency, February 14,  1992, pp.  1-2.

2.  Federal Register, Vol.  56 (20),  part 141.23(lc)(4), pp. 3582-
    3583. Wednesday, January 30,  1991.
                                10

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                                                 ATTACHMENT
                        Application No:,
                                                      (EPA Assigned)'
                                       NPDHR COMPARABILITY STUDY DATA
               Source or Water Supply Identity:	
               Drinking Water Source Type:  Ground
               Constituent Identity:      •	
                                                       Surface
               Concentration Units (weight/volume):
               Initial Sample Constituent Cone. (Before Adjustment).
                                            	  or by Fort1fy1ng_
Initial Sample Adjustment
by D11ut1on_
                               (specify )
                                                      (spec1fy we1ght/volume)
        Theoretical Cone.
                   Approved Method Observations
Proposed Method Observations
Sub-
samp
1
2
3
4
Amount
Added4
0



Total
Cone *




Replicate
1




Replicate
2




Replicate
3




Replicate
1




Replicate
2




Replicate
3




* Identify the applicant or source of data ONLY by the EPA-assigned application number.
+ See pp. 7-9 of the protocol for a discussion of how these concentrations are derived.

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