METHOD 300.1

   DETERMINATION OF INORGANIC ANIONS IN DRINKING WATER BY ION
                          CHROMATOGRAPHY
                               Revision 1.0
John D. Pfaff (USEPA, ORD, NERL) - Method 300.0, (1993)

Daniel P. Hautman (USEPA, Office of Water) and David J. Munch (USEPA, Office of Water)
-Method 300.1, (1997)
             NATIONAL EXPOSURE RESEARCH LABORATORY
               OFFICE OF RESEARCH AND DEVELOPMENT
              U.S. ENVIRONMENTAL PROTECTION AGENCY
                        CINCINNATI, OHIO 45268
                                 300.1-1

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               ERRATA COVER SHEET TO U.S.EPA METHOD 300.1
                                        April 27,1999

The following were editorial changes which have been incorporated into U.S.EPA Method 300.1. These
minor clarifications are incorporated into the body of this text as follows:

ERRATA #1 -
An additional sentence was added to Section 4.1.1 reiterating the analyst's responsibilities when
incorporating any method change, including modifying eluent strength, or any other method parameter.
The additional sentence states,
     "... The analyst must verify that these changes do not negatively affect performance by repeating
     and passing all the QC criteria in Section 9."

On this same theme, section 11.9, was also further clarified and specific precautions were added as
follows,
     " ...The analysts  must verify that this dilution does not negatively affect performance by repeating
     and passing all the QC criteria in Section 9. As a specific precaution, upon dilution of the
     carbonate eluent, apeak for bicarbonate may be observed within the retention time window for
     br-ornate which will negatively impact the analysis."

ERRATA #2 -
An acronym in Section 9.3.2.2 for Laboratory Fortified Blank (LFB) was  incorrectly identified as LRB.
This typographical  error was corrected.

ERRATA #3 -
Clarifications and corrections were made to Section 9.4.1.5, 9.4.3.2 and 9.4.3.3. These clarifications
pertain to data reportability for Laboratory Fortified Sample Matrices (LFM) as well as to analysis
continuation when Duplicate Sample QC acceptance criteria are not met.

Section 9.4.1.5 clarifies and now specifies how to report data when the LFM recovery falls outside the
established control  criteria by stating,
     "...the recovery problem encountered with the LFM is judged to be matrix induced and the results
     for that sample and the LFM are reported with a "matrix induced  bias " qualifier."

Section 9.4.3.2 required the correction of a typographical reference by removing "%Diff" in the duplicate
sample acceptance criteria and replacing it with the defined RPD, indicating "relative percent difference".

Section 9.4.3.3,  also had a "%Diff" reference corrected with RPD and included clarification regarding
continuation of an analysis set when  a duplicate analysis fails to meet the acceptance criteria.  This section
now reads,
     "If the RPD fails to meet these criteria, the samples must be reported with a qualifier identifying
     the sample analysis result as yielding a poor duplicate analysis RPD. This should not be  a
     chronic problem and if it frequently recurs, (>20% of duplicate analysis) it indicates a problem
     with the instrument or individual technique."
                                   ERRATA COVER SHEET

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                                  METHOD 300.1

       DETERMINATION OF INORGANIC ANIONS IN DRINKING WATER
                          BY ION CHROMATOGRAPHY
1.     SCOPE AND APPLICATION

      1.1   This method covers the determination of the following inorganic anions in reagent
           water, surface water, ground water, and finished drinking water. As a result of
           different specified injection volumes (See conditions in Tables 1A and IB), these
           anions are divided between the common anions listed in Part A and the inorganic
           disinfection by-products listed in Part B. These different injection volumes are
           required in order to compensate for the relative concentrations of these anions in
           drinking water and maintain good chromatographic peak shape  throughout the
           expected dynamic range of the detector.  Bromide is included in both Part A, due
           to its importance as a common anion, as well as Part B due to its critical role as a
           disinfection by-product precursor.

           PART A. Common Anions
           Bromide              Nitrite
           Chloride              ortho-Phosphate-P
           Fluoride               Sulfate
           Nitrate

           PART B. Inorganic Disinfection By-products
           Bromate              Chlorite
           Bromide              Chlorate

      1.2   The single laboratory Method Detection Limits (MDL, defined in Sect.  3.11) for
           the above analytes are listed in Tables 1 A, IB and 1C.  The MDL for a specific
           matrix may differ from those listed, depending upon the nature of the sample and
           the specific instrumentation  employed.

           1.2.1  In order to achieve comparable detection limits, an ion chromatographic
                  system must utilize  suppressed conductivity detection, be properly
                  maintained and must be capable of yielding a baseline with no more than
                  5 nS noise/drift per  minute of monitored response over the background
                  conductivity.

      1.3   This method is recommended for use only by or under the supervision of analysts
           experienced in the use of ion chromatography and in the interpretation of the
           resulting ion chromatograms.

      1.4   When this method is used to analyze unfamiliar samples for any of the above
           anions, anion identification should be supported by the use of a fortified sample
           matrix covering the anions of interest. The fortification procedure is described in
           Sect. 9.4.1.

                                       300.1-2

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      1.5   Users of the method data should state the data-quality objectives prior to analysis.
           Users of the method must demonstrate the ability to generate acceptable results
           with this method, using the procedures described in Sect. 9.0.

      1.6   Bromide and nitrite react with most oxidants employed as disinfectants.  The
           utility of measuring these anions in treated water should be considered prior to
           conducting the analysis.

2.    SUMMARY OF METHOD

      2.1   A small volume of sample, 10 uL for Part A and 50 uL for Part B, is introduced
           into an ion chromatograph. The anions of interest are separated and measured,
           using a system comprised of a guard column, analytical column, suppressor
           device, and conductivity detector.

      2.2   The ONLY difference between Parts A and B is the volume of sample analyzed
           by the ion chromatographic system. The separator columns and guard columns as
           well as eluent conditions are identical.

3.    DEFINITIONS

      3.1   ANALYSIS BATCH -- A group of no more than 20 field samples (Field sample
           analyses include only those samples derived from a field sample matrix. These
           include the initial and duplicate field samples as well as all Laboratory Fortified
           Sample Matrices). The analysis batch must include an Initial Calibration Check
           Standard, an End Calibration Check Standard, Laboratory Reagent Blank, and a
           Laboratory Fortified Blank.  Within an ANALYSIS BATCH, for every group of
           ten field samples, at least one Laboratory Fortified Matrix (LFM) and either a
           Field Duplicate, a Laboratory Duplicate or a duplicate of the LFM must be
           analyzed.  When more than 10 field samples are analyzed, a Continuing
           Calibration Check Standard must be analyzed after the tenth field  sample analysis.

      3.2   CALIBRATION STANDARD (CAL) - A solution prepared from the primary
           dilution standard solution or stock standard solutions and the surrogate analyte.
           The CAL solutions are used to calibrate the  instrument response with respect to
           analyte concentration.

           3.2.1    INITIAL CALIBRATION STANDARDS  -- A series of CAL solutions
                   used to initially establish instrument calibration and develop calibration
                   curves for individual target anions.

           3.2.2   INITIAL CALIBRATION CHECK STANDARD --  An individual CAL
                   solution, analyzed initially, prior to any sample analysis, which verifies
                   previously established calibration curves.

           3.2.3    CONTINUING CALIBRATION CHECK  STANDARD - An individual
                   CAL solution which is analyzed after every tenth field sample analyses
                                      300.1-3

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             which verifies the previously established calibration curves and confirms
             accurate analyte quantitation for the previous ten field samples analyzed.

      3.2.4   END CALIBRATION CHECK STANDARD - An individual CAL
             solution which is analyzed after the last field sample analyses which
             verifies the previously established calibration curves and confirms
             accurate analyte quantitation for all field samples analyzed since the last
             continuing calibration check.

3.3    FIELD DUPLICATES  Two separate samples collected at the same time and
      place under identical circumstances  and treated exactly the same throughout field
      and laboratory procedures.  Analyses of field duplicates indicate the precision
      associated with sample collection, preservation and storage, as well as with
      laboratory procedures.

3.4    INSTRUMENT PERFORMANCE  CHECK SOLUTION (IPC) - A solution of
      one or more method analytes, surrogates, or other test substances used to
      evaluate the performance of the instrument system with respect to a defined set of
      criteria.

3.5    LABORATORY DUPLICATE-- Two sample aliquots, taken in the laboratory
      from a single sample bottle, and analyzed separately with identical procedures.
      Analyses of LD1 and LD2 indicate precision associated specifically with the
      laboratory procedures, removing any associated variables attributed by sample
      collection, preservation, or storage procedures.

3.6    LABORATORY FORTIFIED BLANK (LFB) - An aliquot of reagent water or
      other blank matrices to which known quantities of the method analytes are added
      in the laboratory.  The LFB is analyzed exactly like a sample, and its purpose is to
      determine whether the methodology is in control, and whether the laboratory is
      capable of making accurate and precise measurements.

3.7    LABORATORY FORTIFIED SAMPLE MATRIX (LFM)  -- An aliquot of an
      environmental sample to which known  quantities of the method analytes are added
      in the laboratory.  The LFM is analyzed exactly like a sample, and its purpose is to
      determine whether the sample matrix contributes bias to the analytical results. The
      background concentrations of the analytes in the sample matrix must be
      determined in a separate aliquot and the measured values in the LFM corrected for
      background concentrations.

3.8    LABORATORY REAGENT BLANK  (LRB) -- An aliquot of reagent water or
      other blank matrices that are treated exactly as a sample including exposure to all
      glassware, equipment, solvents, reagents, and surrogates that are used with other
      samples. The LRB is used to determine if method analytes  or other interferences
      are present in the laboratory environment, the reagents, or the apparatus.
                                 300.1-4

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      3.9   LINEAR CALIBRATION RANGE (LCR) - The concentration range over which
           the instrument response is linear.

      3.10  MATERIAL SAFETY DATA SHEET (MSDS) -- Written information provided
           by vendors concerning a chemical's toxicity, health hazards, physical properties,
           fire, and reactivity data including storage, spill, and handling precautions.

      3.11  METHOD DETECTION LIMIT (MDL) -- The minimum concentration of an
           analyte that can be identified, measured and reported with 99% confidence that the
           analyte concentration is greater than zero.

      3.12  MINIMUM REPORTING LEVEL (MRL) -- The minimum concentration that
           can be reported for an anion in a sample following analysis.  This defined
           concentration can be no lower than the concentration of the lowest calibration
           standard and can  only be used if acceptable quality control criteria for this standard
           are met.

      3.13  PERFORMANCE EVALUATION SAMPLE (PE) - A certified solution of
           method analytes whose concentration is unknown to the analyst. Often, an aliquot
           of this solution is added to a known volume of reagent water and analyzed with
           procedures used for samples. Results of analyses are used to determine
           statistically the accuracy and precision that can be expected when a method is
           performed by a competent analyst.

      3.14  QUALITY CONTROL SAMPLE (QCS) - A solution of method analytes of
           known concentrations that is used to fortify an aliquot of LRB or sample matrix.
           The QCS is obtained from a source external to the laboratory and different from
           the source of calibration standards. It is used to check laboratory performance
           with externally prepared test materials.

      3.15  SURROGATE ANALYTE - An analyte added to a sample, which is unlikely to
           be found in any sample at significant concentration, and which is added directly to
           a sample aliquot in known amounts before any sample processing procedures are
           conducted.  It is measured with the same procedures used to measure other sample
           components. The purpose of the surrogate analyte is to monitor method
           performance with each sample.

      3.16  STOCK STANDARD SOLUTION (SSS) -- A concentrated solution containing
           one or more method analytes prepared in the laboratory using assayed reference
           materials or purchased from a reputable commercial source.

4.     INTERFERENCES

      4.1   Interferences can  be divided into three different categories:  direct
           chromatographic  coelution, where an analyte response is observed at very nearly
           the same retention time as the target anion; concentration dependant coelution,
           which is observed when the response of higher than typical concentrations of the

                                       300.1-5

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      neighboring peak overlap into the retention window of the target anion; and, ionic
      character displacement, where retention times may significantly shift due to the
      influence of high ionic strength matrices (high mineral content or hardness)
      overloading the exchange sites in the column and significantly shortening target
      analyte's retention times.

      4.1.1    A direct chromatographic coelution may be solved by changing columns,
              eluent strength, modifying the eluent with organic solvents (if compatible
              with 1C columns), changing the detection systems, or selective removal of
              the interference with pretreatment. Sample dilution will have little to no
              effect. The analyst must verify that these changes do not negatively affect
              performance by repeating and passing all the QC criteria in Section 9.

      4.1.2    Sample dilution may resolve some of the difficulties if the interference is
              the result of either concentration dependant coelution or ionic character
              displacement, but it must be clarified that sample dilution will alter your
              Minimum Reporting Limit (MRL) by a proportion equivalent to that of
              the dilution. Therefore, careful consideration of project objectives  should
              be given prior to performing such a dilution.  An alternative to sample
              dilution, may be dilution of the eluent  as outlined in 11.9.

      4.1.3    Pretreatment cartridges can be effective as a means to eliminate certain
              matrix interferences. Prior to using any pretreatment, the analyst should
              be aware that all instrument calibration standards must be pretreated in
              exactly the same manner as the pretreated unknown field samples.  The
              need for these cartridges have been greatly reduced with recent advances
              in high capacity anion exchange columns.

              4.1.3.1   Extreme caution should be exercised in using these
                       pretreatment cartridges. Artifacts are known to leach from
                       certain cartridges which can foul the guard and analytical
                       columns causing loss of column capacity indicated by
                       shortened retention times and irreproducible results.
                       Frequently compare your calibration standard chromatograms
                       to those of the column test chromatogram (received when the
                       column was purchased) to insure proper separation and  similar
                       response ratios between the target analytes is observed.

4.2   Method interferences may be caused by contaminants in the reagent water,
      reagents, glassware, and other sample processing apparatus that lead to discrete
      artifacts or elevated baselines in an ion chromatogram.  These interferences can
      lead to false positive results for target analytes as well as reduced detection limits
      as a consequence of elevated baseline noise.

4.3   Samples that contain particles larger than 0.45 microns and reagent solutions that
      contain particles larger than 0.20 microns require filtration to prevent damage to
      instrument columns and flow systems.
                                  300.1-6

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      4.4   Any anion that is only weakly retained by the column may elute in the retention
           time window of fluoride and potentially interfere. At concentrations of fluoride
           above 1.5 mg/L, this interference may not be significant, however, it is the
           responsibility of the user to generate precision and accuracy information in each
           sample matrix.

      4.5   Close attention should be given to the potential for carry over peaks from one
           analysis which will effect the proper detection of analytes of interest in a second,
           subsequent analysis. Normally, the elution of sulfate (retention time of 13.8 min.)
           indicates the end of a chromatographic run, but, in the ozonated and chlorine
           dioxide matrices, which were included as part of the single operator accuracy and
           bias study  (See Table 2B), a small response (200 nS baseline rise) was observed
           for a very late eluting unknown peak at approximately 23 minutes.  Consequently,
           a run time  of 25 minutes is recommended to allow for the proper elution of any
           potentially interferant late peaks.  It is the responsibility of the user to confirm
           that no late eluting peaks have carried over into a subsequent analysis thereby
           compromising the integrity of the analytical results.

      4.6   Any residual chlorine dioxide present in the sample will result in the formation of
           additional chlorite prior to analysis. If any concentration of chlorine dioxide is
           suspected in the sample, the sample must be purged with an inert gas (helium,
           argon or nitrogen) for approximately five minutes or until no chlorine dioxide
           remains. This sparging must be conducted prior to ethylenediamine preservation
           and at time of sample collection.
5.    SAFETY
      5.1    The toxicity or carcinogenicity of each reagent used in this method have not been
            fully established. Each chemical should be regarded as a potential health hazard
            and exposure should be as low as reasonably achievable. Cautions are included
            for known extremely hazardous materials or procedures.

      5.2    Each laboratory is responsible for maintaining a current awareness file of OSHA
            regulations regarding the safe handling of the chemicals specified in this method.
            A reference file of Material Safety Data Sheets (MSDS) should be made available
            to all personnel involved in the chemical analysis. The preparation of a formal
            safety plan is also advisable.

      5.3    The following chemicals have the potential to be highly toxic or hazardous,
            consult MSDS.

            5.3.1   Sulfuric acid - When used to prepared a 25 mN sulfuric acid regenerant
                   solution for chemical suppression using a Dionex Anion Micro Membrane
                   Suppressor (AMMS).
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6.     EQUIPMENT AND SUPPLIES

      6.1   Ion chromatograph  Analytical system complete with ion chromatograph and all
           required accessories including syringes, analytical columns, compressed gasses
           and a conductivity detector.

           6.1.1    Anion guard column: Dionex AG9-HC, 2 mm (P/N 52248), or
                   equivalent.  This column functions as a protector of the separator column.
                   If omitted from the system the retention times will be shorter.

           6.1.2    Anion separator column: Dionex AS9-HC column, 2 mm (P/N 52244),
                   or equivalent.  The microbore (2 mm) was selected in the development of
                   this method as a means to tighten the bromate elution band and thus
                   reduce the detection limit. An optional column (2 mm or 4 mm) may be
                   used if comparable resolution of peaks is obtained,  and the requirements
                   of Sect. 9.0  can be met.  The AS9-HC, 2 mm column using the conditions
                   outlined in Table 1A and IB produced the separation shown in Figures 1
                   through 4.

                   6.1.2.1    If a 4 mm column is employed, the injection volume should be
                            raised by a factor of four to 40 uL for Part A anions and 200
                            uL for Part B anions in order to attain comparable detection
                            limits.  A four fold increase in injection volume compensates
                            for the four fold increase in cross  sectional surface area of the
                            4 mm standard bore column over the 2 mm microbore column.

                   6.1.2.2   Comparable results can be attained using the Dionex, AS9-HC,
                            4 mm column. MDLs for the part B, inorganic disinfection by-
                            products using this 4 mm column  are displayed along with
                            analysis conditions in Table 1C.

           6.1.3    Anion suppressor device: The data presented in this method were
                   generated using a Dionex Anion Self Regenerating Suppressor (ASRS,
                   P/N 43187). An equivalent suppressor device may be utilized provided
                   comparable detection limits are achieved and adequate baseline stability is
                   attained as measured by a combined baseline drift/noise of no more than 5
                   nS per minute over the background conductivity.

                   6.1.3.1    The ASRS was set to perform electrolytic suppression at a
                            current  setting of 100 mA using an external source DI water
                            mode. Insufficient baseline stability was observed using the
                            ASRS in recycle mode.

           6.1.4    Detector  Conductivity cell (Dionex CD20, or equivalent) capable of
                   providing data as required in Sect. 9.2.
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      6.2   The Dionex Peaknet Data Chromatography Software was used to generate all the
           data in the attached tables. Systems using a strip chart recorder and integrator or
           other computer based data system may achieve approximately the same MDL's
           but the user should demonstrate this by the procedure outlined in Sect. 9.2.

      6.3   Analytical balance, 0.1 mg sensitivity. Used to accurately weigh target analyte
           salts for stock standard preparation.

      6.4   Top loading balance, 10 mg sensitivity.  Used to accurately weigh reagents to
           prepare eluents.

      6.5   Weigh boats, plastic, disposable - for weighing eluent reagents.

      6.6   Syringes,  plastic, disposable, 10 mL - used during sample preparation.

      6.7   Pipets, Pasteur, plastic or glass, disposable, graduated, 5 mL and 10 mL.

      6.8   Bottles, high density polyethylene (HDPE), opaque or glass, amber, 30 mL, 125
           mL, 250 mL.  For  sampling and storage of calibration solutions.  Opaque or
           amber due to the photoreactivity of chlorite anion.

      6.9   Micro beakers, plastic, disposable - used during sample preparation.

7.     REAGENTS AND STANDARDS

      7.1   Reagent water: Distilled or deionized water, free of the anions of interest.  Water
           should contain particles no larger than 0.20 microns.

      7.2   Eluent solution : Sodium carbonate (CASRN 497-19-8) 9.0 mM. Dissolve 1.91
           g sodium  carbonate (Na2CO3) in reagent water and  dilute to 2 L.

           7.2.1    This eluent solution must be purged for 10 minutes with helium prior to
                   use to remove dissolved gases which may form micro bubbles in the 1C
                   compromising system performance and adversely effecting the integrity of
                   the data.

      7.3   Stock standard solutions, 1000 mg/L (1 mg/mL): Stock standard solutions may
           be purchased as certified solutions or prepared from ACS reagent grade,
           potassium or sodium salts as listed below, for most  analytes. Chlorite requires
           careful consideration as outline below in 7.3.5.1.

           7.3.1    Bromide (Bf) 1000 mg/L: Dissolve 0.1288 g sodium bromide (NaBr,
                   CASRN 7647-15-6) in reagent  water and dilute to 100 mL in a
                   volumetric flask.
                                       300.1-9

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7.3.2   Bromate (BrO3") 1000 mg/L: Dissolve 0.1180 g of sodium bromate
       (NaBrO3, CASRN 7789-38-0) in reagent water and dilute to 100 mL in a
       volumetric flask.

7.3.3   Chlorate (C1(V) 1000 mg/L: Dissolve 0.1275 g of sodium chlorate
       (NaC103, CASRN 7775-09-9) in reagent water and dilute to 100 mL in a
       volumetric flask.

7.3.4   Chloride (Cl') 1000 mg/L:  Dissolve 0.1649 g sodium chloride (NaCl,
       CASRN 7647-14-5) in reagent water and dilute to 100 mL in a
       volumetric flask.

7.3.5   Chlorite (C102~) 1000 mg/L:  Assuming an exact 80.0 % NaC102 is
       amperometrically titrated from technical grade NaC102(See Sect.
       7.3.5.1). Dissolve 0.1676 g of sodium chlorite (NaC102, CASRN 7758-
       19-2) in reagent water and dilute to 100 mL in a volumetric flask.

       7.3.5.1   High purity sodium chlorite (NaCIO2) is not currently
                commercially available due to potential explosive instability.
                Recrystallization of the technical grade (approx. 80%) can be
                performed but it is labor intensive and time consuming. The
                simplest approach is to determine the exact % NaCIO 2 using
                the iodometric titration procedure (Standard Methods, 19th
                Ed., 4500-C1O2.C). Following titration, an individual
                component  standard of chlorite must be analyzed to determine
                if there is any significant contamination (greater than  1% of the
                chlorite weight) in the technical grade chlorite standard from
                any of the Part B components. These contaminants will place
                a high bias on the calibration of the other anions if all four Part
                B components are mixed in an combined calibration solution.
                If these other anions are present as contaminants, a separate
                chlorite calibration needs to be performed.

7.3.6   Fluoride (F) 1000 mg/L:  Dissolve 0.2210 g sodium fluoride (NaF,
       CASRN 7681-49-4) in reagent water and dilute to 100 mL in a
       volumetric flask.

7.3.7   Nitrate (NO>N) 1000 mg/L: Dissolve 0.6068 g sodium nitrate (NaNO3,
       CASRN 7631-99-4) in reagent water and dilute to 100 mL in a
       volumetric flask.

7.3.8   Nitrite (NO>N) 1000 mg/L: Dissolve 0.4926 g sodium nitrite (NaNO2,
       CASRN 7632-00-0) in reagent water and dilute to 100 mL in a
       volumetric flask.
                           300.1-10

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           7.3.9   Phosphate (PO43'-P) 1000 mg/L: Dissolve 0.4394 g potassium
                   dihydrogenphosphate (KH2PO4, CASRN 7778-77-0) in reagent water
                   and dilute to 100 mL in a volumetric flask.

           7.3.10  Sulfate (SO42') 1000 mg/L: Dissolve 0.1814 g potassium sulfate (K2SO4,
                   CASRN 7778-80-5) in reagent water and dilute to 100 mL in a
                   volumetric flask.

           NOTE:     Stability of standards: Stock standards (7.3) for most anions are
                       stable for at least 6 months when stored at 4C.  Except for the
                       chlorite standard which is only stable for two weeks when stored
                       protected from light at 4C, and nitrite and phosphate which are only
                       stable for 1 month when stored at 4C.  Dilute working standards
                       should be prepared monthly, except those that contain chlorite, or
                       nitrite and phosphate which should be prepared fresh daily.

      7.4   Ethylenediamine (EDA) preservation solution, 100 mg/mL: Dilute 2.8 mL of
           ethylenediamine (99%) (CASRN 107-15-3) to 25 mL with reagent water.
           Prepare fresh monthly.

      7.5   Surrogate Solution: 0.50 mg/mL dichloroacetate (DCA) prepared by dissolving
           0.065 g dichloroacetic acid, potassium salt (C12CHCO2K, CASRN 19559-59-2) in
           reagent water and dilute to 100 mL in a volumetric flask.

           7.5.1   Dichloroacetate is potentially present in treated drinking waters as the
                   acetate of the organic disinfection by product, dichloroacetic acid
                   (DCAA). Typical concentrations of DCAA rarely exceed 50 ug/L,
                   which, for this worst case example, would represent only a five percent
                   increase in the observed response over the fortified concentration of 1.00
                   mg/L.  Consequently, the criteria for acceptable recovery (90% to 115%)
                   for the surrogate is weighted to 115% to allow for this potential
                   background.

           7.5.2   Prepare this solution fresh every 3 months or sooner if signs of
                   degradation are present.

8.     SAMPLE COLLECTION. PRESERVATION AND STORAGE

      8.1   Samples should be collected in plastic or glass bottles. All bottles must be
           thoroughly cleaned and rinsed with reagent water. Volume collected should be
           sufficient to insure a representative sample, allow for replicate analysis, if
           required, and minimize waste disposal.

      8.2   Special sampling requirements and precautions for chlorite.

           8.2.1   Sample bottles used for chlorite analysis must be opaque to protect the
                   sample from light.

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      8.2.2   When preparing the LFM, be aware that chlorite is an oxidant and may
             react with the natural organic matter in an untreated drinking water
             matrix as a result of oxidative demand. If untreated water is collected for
             chlorite analysis, and subsequently used for the LFM, EDA preservation
             will not control this demand and reduced chlorite recoveries may be
             observed.

 .3   Sample preservation and holding times for the anions that can be determined by
      this method are as follows:
      PART A :  Common Anions
Analyte
Bromide
Chloride
Fluoride
Nitrate-N
Nitrite-N
ortho-Phosphate-P
Sulfate
PART B : Inorganic
Analyte
Bromate
Bromide
Chlorate
Chlorite
Preservation
None required
None required
None required
Cool to 4C
Cool to 4C
Cool to 4C
Cool to 4C
Disinfection Bv-products
Preservation
50 mg/L EDA
None required
50 mg/L EDA
50 mg/L EDA, Cool to 4C
                                                               Holding Time
                                                               28 days
                                                               28 days
                                                               28 days
                                                               48 hours
                                                               48 hours
                                                               48 hours
                                                               28 days
                                                               Holding Time
                                                               28 days
                                                               28 days
                                                               28 days
                                                               14 days
8.4   When collecting a sample from a treatment plant employing chlorine dioxide, the
      sample must be sparged with an inert gas (helium, argon, nitrogen) prior to
      addition of the EDA preservative at time of sample collection.

8.5   All four anions, in Part B, can be analyzed in a sample matrix which has been
      preserved with EDA.  Add a sufficient volume of the EDA preservation solution
      (Sect. 7.4) such that the final concentration is 50 mg/L in the sample.  This would
      be equivalent to adding 0.5 mL of the EDA preservation solution to 1 L of
      sample.

8.6   EDA is primarily used as a preservative for chlorite.  Chlorite is susceptible to
      degradation both through catalytic reactions with dissolved iron salts and
      reactivity towards free chlorine which exists as hypochlorous acid/hypochlorite
      ion in most drinking water as a residual disinfectant.  EDA serves a dual purpose
      as a preservative for chlorite by chelating iron as well as any other catalytically
      destructive metal cations and removing hypochlorous acid/hypochlorite ion by
      forming an organochloroamine.  EDA preservation of chlorite also preserves the
      integrity of chlorate which can increase in unpreserved samples as a result of
      chlorite degradation.  EDA also preserves the integrity of bromate concentrations
      by binding with hypobromous acid/hypobromite which is an intermediate formed
                                 300.1-12

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           as by-product of the reaction of either ozone or hypochlorous acid/hypochlorite
           with bromide ion. If hypobromous acid/hypobromite is not removed from the
           matrix further reactions may form bromate ion.

      8.7   Degradation of ortho-phosphate has been observed in samples held at room
           temperature for over 16 hrs (see table 3 A). Therefore, samples to be analyzed for
           ortho-phosphate must not be held at room temperature for more than 12
           cumulative hours.

9.     QUALITY CONTROL

      9.1   Each laboratory using this method is required to operate a formal quality  control
           (QC) program.  The requirements of this program consist of an initial
           demonstration of laboratory performance, and subsequent analysis in each
           analysis batch (Sect. 3.1) of a Laboratory Reagent Blank, Laboratory Fortified
           Blank, Instrument Performance Check Standard, calibration check standards,
           Laboratory Fortified Sample Matrices (LFM) and either Field, Laboratory or
           LFM duplicate sample analyses.  This section details the specific requirements for
           each of these QC parameters.  The laboratory is required to maintain performance
           records that define the quality of the data that are generated.

      9.2   INITIAL DEMONSTRATION OF PERFORMANCE

           9.2.1  The initial demonstration of performance is used to characterize
                  instrument performance (determination of accuracy through the analysis
                  of the QCS) and laboratory performance (determination of MDLs) prior
                  to performing analyses by this method.

           9.2.2  Quality Control Sample (QCS) - When beginning the use of this method,
                  on a quarterly basis or  as required to meet data-quality needs, verify the
                  calibration standards and acceptable instrument performance with the
                  preparation and analyses  of a QCS. If the determined concentrations are
                  not within  15% of the stated values, performance of the determinative
                  step of the method is unacceptable. The source of the problem must be
                  identified and corrected before either proceeding with the initial
                  determination of MDLs or continuing with on-going  analyses.

           9.2.3  Method Detection Limit (MDL) - MDLs must be  established for all
                  analytes, using reagent water (blank) fortified at a  concentration of three
                  to five times the estimated instrument detection limit.(6) To determine
                  MDL values, take seven replicate aliquots of the fortified reagent water
                  and process through the entire analytical method over at least three
                  separate days. Perform all calculations defined in the method and report
                  the concentration values in the appropriate units. Calculate the MDL as
                  follows:

                                   MDL = (t) x (S)
                                       300.1-13

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             where,   t =   Student's t value for a 99% confidence level and a
                            standard deviation estimate with n-1 degrees of freedom
                            [t = 3.14 for seven replicates].
                      S =  standard deviation of the replicate analyses.

             9.2.3.1   MDLs should be determined every 6 months, when a new
                      operator begins work or whenever there is a significant change
                      in the background, or instrument response.

9.3   ASSESSING LABORATORY PERFORMANCE

      9.3.1   Laboratory  Reagent Blank (LRB)  The laboratory must analyze at least
             one LRB with each analysis batch (defined Sect 3.1).  Data produced are
             used to assess contamination from the laboratory environment. Values
             that exceed the MDL indicate laboratory or reagent contamination should
             be suspected and corrective actions must be taken before continuing the
             analysis.

             9.3.1.1   If conducting analysis for the Part B anions, EDA must be
                      added to the LRB at 50 mg/L.  By including EDA in the LRB,
                      any bias as a consequence of the EDA which may be observed
                      in the field samples, particularly in terms of background
                      contamination, will be identified.

      9.3.2   Laboratory  Fortified Blank (LFB)  The LFB should be prepared at
             concentrations similar to those expected in the field samples and ideally at
             the same concentration used to prepare the LFM. Calculate accuracy as
             percent recovery (Sect. 9.4.1.3).  If the recovery of any analyte falls
             outside the  required concentration dependant control limits (Sect.
             9.3.2.2), that analyte is judged out of control, and the source of the
             problem should be identified and resolved before continuing analyses.

             9.3.2.1   If conducting analysis for the Part B anions, EDA must be
                      added to the LFB at 50 mg/L.  The addition of EDA to all
                      reagent water prepared calibration and quality  control samples
                      is required not as a preservative but rather as a means to
                      normalize any bias attributed by the presence of EDA in the
                      field samples.

             9.3.2.2   Control Limits for the LFB

                 Concentration range                    Percent Recovery Limits
                   MRL to lOxMRL                     75-125 %
             1 OxMRL to highest calibration level          85 - 115 %
                                 300.1-14

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       9.3.2.2. 1  These control limits only apply if the MRL is established within
                 a factor of 10 times the MDL. Otherwise, the limits are set at
                 85% to 115%.

       9.3.2.3    The laboratory must use the LFB to assess laboratory perfor-
                 mance against the required control limits listed in 9.3.2.2.
                 When sufficient internal performance data become available
                 (usually a minimum of 20-30 analyses), optional control limits
                 can be developed from the percent mean recovery (x) and the
                 standard deviation (S) of the mean recovery. These data can
                 be used to establish the upper and lower control  limits as
                 follows:

                     UPPER CONTROL LIMIT = x + 3S
                     LOWER CONTROL LIMIT = x - 3S

                 The optional control limits must be equal to or better than
                 those listed in 9.3.2.2. After each five to ten new recovery
                 measurements, new control limits can be calculated using only
                 the most recent 20-30 data points. Also, the standard
                 deviation (S) data should be used to establish an on-going
                 precision statement for the level of concentrations monitored.
                 These data must be kept on file and be available for review.

9.3.3   Instrument Performance Check Solution (TPC)   The Initial Calibration
       Check Standard is to be evaluated as the instrument  performance check
       solution in order to confirm proper instrument performance.  Proper
       chromatographic performance must be demonstrated by calculating the
       Peak Gaussian Factor (PGF), which is a means to measure  peak
       symmetry and monitoring retention time drift in the  surrogate peak over
       time. Critically evaluate the surrogate peak in the initial calibration check
       standard, and calculate the PGF as follows,

                          1.83 x W(l/2)
                  PGF =  -----------------------
         where:  W(l/2) is the peak width at half height
                       W(l/10) is the peak width at tenth height

       9.3.3.1    The PGF must fall between 0.80 and 1.15 in order to
                 demonstrate proper instrument performance.

       9.3.3.2   The retention time for the surrogate in the IPC must be closely
                monitored on each day of analysis and throughout the lifetime of
                the analytical column.  Small variations in retention time can be
                anticipated when a new solution of eluent is prepared but if
                shifts of more than 2% are observed in the surrogate retention
                time, some type of instrument problem is present. Potential

                           300.1-15

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                     problems include improperly prepared eluent, erroneous method
                     parameters programmed such as flow rate or some other system
                     problem. The chromatographic profile (elution order) of the
                     target anions following an ion chromatographic analysis should
                     closely replicate the profile displayed in the test chromatogram
                     that was shipped when the column was purchased. As a column
                     ages, it is normal to see a gradual shift and shortening of
                     retention times, but if after several years of use, extensive use
                     over less than a year, or use with harsh samples, this retention
                     time has noticeably shifted to any less than 80% of the original
                     recorded value, the column may require cleaning or
                     replacement. Particularly if resolution problems are beginning
                     to become common between previously resolved peaks.  A
                     laboratory must retain a historic record of retention times for
                     the surrogate and all the target anions to provide evidence of an
                     analytical columns vitality.

9.4   ASSESSING ANALYTE RECOVERY AND DATA QUALITY

      9.4.1   Laboratory Fortified Sample Matrix (LFM)  The laboratory must add  a
             known amount of analyte to a minimum of 10% of the field samples
             within an analysis batch.  The LFM sample must be prepared from a
             sample matrix which has been analyzed prior to fortification. The analyte
             concentration must be high enough to be detected above the original
             sample and should adhere to the requirement of 9.4.1.2. It is
             recommended that the solutions used to fortify the LFM be prepared
             from the same stocks used to prepare the calibration standards and not
             from external source stocks. This will remove the bias contributed by an
             externally prepared stock and focus on any potential bias introduced by
             the field sample matrix.

             9.4.1.1  If the fortified concentration is less than the observed
                     background concentration of the unfortified matrix, the
                     recovery should not be calculated. This is due to the difficulty
                     in calculating accurate recoveries of the fortified concentration
                     when the native sample concentration is so high.

             9.4.1.2  The LFM should be prepared at concentrations no greater than
                     five times the highest concentration observed in any field
                     sample. If no analyte is observed in any field  sample, the LFM
                     must be fortified no greater than five times the lowest
                     calibration level which as outlined in 12.2 is the minimum
                     reported level (MRL). For example, if bromate is not detected
                     in any field samples above the lowest calibrations standard
                     concentration of 5.00 ug/L, the highest LFM fortified
                     concentration allowed is 25.0 ug/L.
                                300.1-16

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       9.4.1.3   Calculate the percent recovery for each analyte, corrected for
                concentrations measured in the unfortified sample.  Percent
                recovery should be calculated using the following equation:

                              CS-C
                        R= 	 x 100
                where, R =   percent recovery.
                       Cs =   fortified sample concentration
                       C =   sample background concentration
                       s =    concentration equivalent of analyte added to
                              sample.

       9.4.1.4  Until sufficient data becomes available (usually a minimum of 20
                to 30 analysis), assess laboratory performance against recovery
                limits of 75 to 125%. When sufficient internal performance data
                becomes available develop control limits from percent mean
                recovery and the standard deviation of the mean recovery.  The
                optional control limits must be equal to  or better than the
                required control limits of 75-125%.

       9.4. 1.5  If the recovery of any analyte falls outside the designated LFM
                recovery range and the laboratory performance for that analyte
                is shown to be in control (Sect. 9.3), the recovery problem
                encountered with the LFM is judged to be matrix induced and
                the results for that sample and the LFM are reported with a
                "matrix induced bias" qualifier.

9.4.2   SURROGATE RECOVERY - Calculate the surrogate recovery from all
       analyses using the following formula
                        R = --.- x 100
                              SFC

       where,   R  =   percent recovery.
                SRC = Surrogate Recovered Concentration
                SFC = Surrogate Fortified Concentration

       9.4.2. 1   Surrogate recoveries must fall between 90-1 15% for proper
                instrument performance and analyst technique to be verified.  The
                recovery of the surrogate is slightly bias to 115% to allow for the
                potential contribution of trace levels of dichloroacetate as the
                halogenated organic disinfection by-product (DBF) dichloroacetic
                acid (DCAA) Background levels of this organic DBF are rarely
                observed above 50 ug/L (0.05 mg/L) which constitutes only 5%
                of the 1.00 mg/L recommended fortified concentration.

       9.4.2.2   If the surrogate recovery falls outside the 90-1 15% recovery
                window, a analysis error is evident and sample reanalysis is

                            300.1-17

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                required. Poor recoveries could be the result of imprecise sample
                injection or analyst fortification errors.

9.4.3   FIELD OR LABORATORY DUPLICATES -- The laboratory must
       analyze either a field or a laboratory duplicate for a minimum of 10% of the
       collected field samples or at least one with every analysis batch, whichever
       is greater.  The sample matrix selected for this duplicate analysis must
       contain measurable concentrations of the target anions in order to establish
       the precision of the analysis set and insure the quality of the data. If none
       of the samples within an analysis batch have measurable concentrations, the
       LFM should be employed as a laboratory duplicate.

       9.4.3.1   Calculate the relative percent difference (RPD) of the initial
                quantitated concentration (Ic) and duplicate quantitated
                concentration (Dc) using the following formula,

                              (ic-Dc)
                     RPD =	X 100
                           (Pc + DJ/2)

       9.4.3.2  Duplicate analysis acceptance criteria

                Concentration range                        RPD Limits
                  MRL to 1 OxMRL                        +/- 20 %
                  lOxMRL to highest calibration level        +/- 10 %

       9.4.3.3   If the RPD fails to meet these criteria, the samples must be
                reported with a qualifier identifying the sample analysis result as
                yielding a poor duplicate  analysis RPD. This should not be a
                chronic problem and if it  frequently recurs (>20% of duplicate
                analyses) it indicates a problem with the instrument or individual
                technique.

9.4.4   Where reference materials are available, they should be analyzed to provide
       additional performance data. The analysis of reference samples is a
       valuable tool for demonstrating the ability  to perform the method
       acceptably.

9.4.5   In recognition of the rapid advances occurring in chromatography, the
       analyst is permitted certain options, such as the use of different columns,
       injection volumes, and/or eluents, to improve the separations or lower the
       cost of measurements. Each time such modifications to the method are
       made, the analyst is  required to repeat the  procedure in Sect. 9.2 and
       adhere to the condition of baseline stability found in Sect. 1.2.1.

9.4.6   It is recommended that the laboratory adopt additional quality assurance
       practices for use with this method.  The specific practices that are most

                            300.1-18

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                   productive depend upon the needs of the laboratory and the nature of the
                   samples. Whenever possible, the laboratory should perform analysis of
                   quality control check samples and participate in relevant performance
                   evaluation sample studies.

10.   CALIBRATION AND STANDARDIZATION

      10.1  Establish ion chromatographic operating parameters equivalent to those indicated
           in Tables 1A or IB if employing a 2 mm column, Table 1C if employing a 4 mm
           column.

      10.2  Estimate the Linear Calibration Range (LCR)  The LCR should cover the
           expected concentration range of the field samples and should not extend over
           more than 2 orders of magnitude in concentration (For example, if quantitating
           nitrate in the expected range of 1.0  mg/L to 10 mg/L, 2 orders of magnitude
           would permit the minimum  and maximum calibration standards of 0.20 mg/L and
           20 mg/L, respectively.) The restriction of 2 orders of magnitude is prescribed
           since beyond this it is  difficult to maintain linearity throughout the entire
           calibration range.

           10.2.1  If quantification is desired over a larger range, then two separate
                   calibration curves should be prepared.

           10.2.2  For an individual calibration curve, a minimum of three calibration
                   standards are required for a curve that extends over a single order of
                   magnitude and a minimum  of five calibration standards are required if the
                   curve covers two orders of magnitude. (For example, using the nitrate
                   example cited above in section 10.2, but in this case limit the curve to
                   extend only from 1.0 mg/L to 10 mg/L or a single order of magnitude. A
                   third standard is required somewhere in the middle of the range. For the
                   calibration range of 0.20 mg/L to 20 mg/L, over two orders of
                   magnitude, five calibrations standards should be employed, one each at
                   the lower and upper concentration ranges and the other three
                   proportionally divided throughout the middle of the curve.)

      10.3  Prepare the calibration standards by carefully adding measured volumes of one or
           more stock standards (7.3) to a volumetric flask and diluting to volume with
           reagent water.

           10.3.1  For the Part B anions, EDA must be added to the calibration standards at
                   50 mg/L.  The addition of EDA to all reagent water prepared calibration
                   and quality control  samples is required not as a preservative but rather as
                   a means to normalize any bias attributed by the presence of EDA in the
                   field samples.

           10.3.2  Prepare a 10.0 mL aliquot of surrogate fortified calibration solution
                   which can be held for direct manual injection or used to fill an
                   autosampler vial. Add 20 uL of the surrogate solution (7.5) to a 20 mL
                   disposable plastic micro beaker. Using a 10.0 mL disposable pipet, place

                                       300.1-19

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             exactly 10.0 mL of calibration standard into the micro beaker and mix.
             The calibration standard is now ready for analysis.  The same surrogate
             solution that has been employed for the standards should also be used in
             the section 11.3.2 for the field samples.

10.4  Using a 2 mm column, inject 10 uL (Part A) or 50 uL (Part B) of each calibration
      standard. Using a 4 mm column, inject 50 uL (Part A) or 200 uL (Part B) of each
      calibration standard.  Tabulate peak area responses against the concentration.
      The results are used to prepare calibration curves using a linear least squares fit
      for each analyte. Acceptable calibration curves are confirmed after reviewing the
      curves for linearity and passing the criteria for the initial calibration check
      standard in section 10.5.1. Alternately, if the ratio of response to concentration
      (response factor) is constant  over the LCR (indicated by < 15% relative standard
      deviation (RSD), linearity through the origin can be assumed and the average
      ratio or calibration factor can be used in place of a calibration curve,

      10.4.1  Peak areas are strongly recommended since they have been  found to be
             more consistent, in terms of quantitation, than peak heights.  Peak height
             can tend to be suppressed as a result of high levels of common anions in a
             given matrix which can compete for exchange sites.  Using peak areas, it
             is the analyst responsibility to review all chromatograms to insure
             accurate baseline integration of target analyte peaks since poorly drawn
             baselines will  more significantly influence peak areas than peak heights.

10.5  Once the calibration curves have been established they must be verified prior to
      conducting any sample analysis using an initial calibration check standard (3.2.2).
      This verification must be performed on each analysis day or whenever fresh eluent
      has been prepared. A continuing calibration check standard (3.2.3) must be
      analyzed after every tenth sample and at the end of the analysis set as an end
      calibration check standard (3.2.4). The response for the initial, continuing and end
      calibration check  must satisfy the criteria listed in 10.5.1. If during the analysis set,
      the response differs by more  than the calibration verification criteria shown in
      10.5.1., or the retention times shift more than  5% from the expected values for
      any analyte, the test must be  repeated, using fresh  calibration standards.  If the
      results are still outside these criteria, sample analysis must be discontinued, the
      cause  determined and/or in the case of drift, the instrument recalibrated.  All
      samples following the last  acceptable calibration check standard must be
      reanalyzed.

      10.5.1  Control limits for calibration verification

                 Concentration range                     Percent Recovery Limits
                   MRL to lOxMRL                      75-125 %
             1 OxMRL to highest calibration level           85 -  115 %

              10.5.1.1  These control limits only apply if the MRL i s establi shed within
                       a factor of 10 times the MDL.  Otherwise, the limits are set at
                       85% to 115%.

                                  300.1-20

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           10.5.2  CALIBRATION VERIFICATION REQUIREMENT FOR PART B
                   As a mandatory requirement of calibration verification, the laboratory
                   MUST verify calibration using the lowest calibration standard as the
                   initial  calibration check standard.

           10.5.3  After satisfying the requirement of 10.5.2, the levels selected for the other
                   calibration check standards should be varied between a middle calibration
                   level and the highest calibration level.

11.   PROCEDURE

      11.1  Tables 1A and IB summarize the recommended operating conditions for the ion
           chromatograph.  Included in these tables are estimated retention times that can be
           achieved by this method.  Other columns,  chromatographic conditions, or
           detectors may  be used if the requirements of Sect. 9.2 are met.

      11.2  Check system  calibration daily and, if required, recalibrate as described in Sect.
           10.

      11.3  Sample Preparation

           11.3.1  For refrigerated or samples arriving to the laboratory cold, ensure the
                   samples have come to room temperature prior to conducting sample
                   analysis by allowing the samples to warm on the bench for at least 1 hour.

           11.3.2  Prepare a 10.0 mL aliquot of surrogate fortified sample which can be held
                   for direct manual injection or used to fill an autosampler vial.  Add 20 uL
                   of the  surrogate solution (7.5) to a 20 mL disposable plastic micro beaker.
                   Using  a  10.0 mL  disposable pipet, place exactly 10.0 mL of sample into
                   the micro beaker  and mix. Sample is now ready for analysis.

                   11.3.2.1 The less than 1% dilution error introduced by the addition of the
                           surrogate is considered insignificant.

      11.4  Using a Luer lock, plastic 10 mL syringe, withdraw the sample from the micro
           beaker and attach a 0.45 um particulate filter (demonstrated to be free of ionic
           contaminants)  directly to  the syringe.  Filter the sample into an autosampler vial
           (If vial is not designed to  automatically filter) or manually load the injection loop
           injecting a fixed  amount of well mixed sample.  If using a manually loaded
           injection loop,  flush the loop thoroughly between sample analysis using sufficient
           volumes of each new sample matrix.

      11.5  Using a 2 mm  column, inject 10 uL (Part A) or 50 uL (Part B) of each sample.
           Using a 4 mm  column, inject 40 uL (Part A) or 200 uL (Part B) of each sample.
           Tabulate peak area responses against the concentration.  During this procedure,
           retention times must be recorded.  Use the same size loop for standards and
                                      300.1-21

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           samples. Record the resulting peak size in area units. An automated constant
           volume injection system may also be used.

      11.6  The width of the retention time window used to make identifications should be
           based upon measurements of actual retention time variations of standards over the
           course of a day. Three times the standard deviation of a retention time can be
           used to calculate a suggested window size for each analyte. However, the
           experience of the analyst should weigh heavily in the interpretation of
           chromatograms.

      11.7  If the response of a sample analyte  exceeds the calibration range, the sample may
           be diluted with an appropriate amount of reagent water and reanalyzed. If this is
           not possible then three new calibration concentrations must be employed to create
           a separate high concentration curve, one standard near the estimated
           concentration  and the other two bracketing around an interval equivalent to 
           25% the estimated concentration. The latter procedure involves significantly
           more time than a simple sample dilution therefore, it is advisable to collect
           sufficient sample to allow for sample dilution or sample reanalysis, if required.

      11.8  Shifts in retention time are inversely proportional to concentration.  Nitrate,
           phosphate and sulfate will exhibit the greatest degree of change, although all
           anions can be  affected. In some cases this peak migration may produce poor
           resolution or make peak identification difficult.

      11.9  Should more complete resolution be needed between any two coeluting peaks, the
           eluent (7.2) can be diluted. This will spread out the run, however, and will cause
           late eluting anions to be retained even longer.  The analysts must verify that this
           dilution does not negatively affect performance by repeating and passing all the QC
           criteria in Section 9.  As a specific  precaution, upon dilution of the carbonate
           eluent, a peak  for bicarbonate may  be observed within the retention time window
           for bromate which will negatively impact the analysis.

           11.9.1   Eluent dilution will reduce the overall response of an anion due to
                    chromatographic band broadening which will be evident by shortened
                    and  broadened peaks.  This will adversely effect the MDLs for each
                    analyte.

12.   DATA ANALYSIS AND CALCULATIONS

      12.1  Prepare a calibration curve for each analyte by plotting instrument response, as
           peak area, against standard concentration.  Compute sample concentration by
           comparing sample response with the standard curve.  If a sample has been
           diluted, multiply the response by the appropriate dilution factor.

      12.2  Report ONLY those values that fall between the lowest and the highest
           calibration standards.  Samples with target analyte responses exceeding the
           highest standard should be diluted and reanalyzed. Samples with target analytes
           identified but quantitated below the concentration established by the lowest


                                       300.1-22

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           calibration standard should be reported as below the minimum reporting limit
           (MRL).

      12.3  Report results for Part A anions in mg/L and for Part B anions in ug/L.

      12.4  Report   NO2'  asN
                    NO3-  asN
                    HPO4= as P
                    Br" in mg/L when reported with Part A
                    Br" in ug/L when reported with Part B

13.   METHODS PERFORMANCE

      13.1  Tables 1 A, IB, and 1C give the single laboratory (OW OGWDW TSC-
           Cincinnati) retention times, standard conditions and MDL determined for each
           anion included in the method. MDLs for the Part A anions were determined in
           reagent water on the 2 mm column (Table 1 A). MDLs for the Part B anions were
           conducted not only in reagent water but also a  simulated high ionic strength water
           (HIW) on the 2 mm column (Table IB) and in  reagent water on the 4 mm column
           (Table 1C).  HIW is designed to simulate a high ionic strength field sample. It
           was prepared from reagent water which was fortified with the common anions of
           chloride at 100 mg/L, carbonate at 100 mg/L, nitrate at 10.0 mg/L as nitrogen,
           phosphate at 10.0 mg/L as phosphorous, and sulfate at 100 mg/L.

      13.2  Tables 2A and 2B give the single laboratory (OW OGWDW TSC-Cincinnati)
           standard deviation  for each anion included in the method in a variety of waters for
           the standard conditions identified in Table 1A and IB, respectively.

     13.3  Tables 3A and 3B  shown stability  data for the Part A and B anions, respectively.
           Each data point in these tables represent the mean percent recovery following
           triplicate analysis.  These data were used to formulate the holding times shown in
           Sect. 8.3.

14.  POLLUTION PREVENTION

     14.1  Pollution prevention encompasses  any technique that reduces or eliminates the
           quantity or toxicity of waste  at  the point of generation. Numerous opportunities
           for pollution prevention exist in laboratory operation. The EPA has established a
           preferred hierarchy of environmental management techniques that places pollution
           prevention as the management option of first choice.  Whenever feasible,
           laboratory personnel should use pollution prevention techniques to address their
           waste generation. When wastes cannot be feasibly reduced at the source, the
           Agency recommends recycling  as the next best option.

     14.2  Quantity of the chemicals purchased should be based on expected usage during its
           shelf life and disposal cost of unused material.  Actual reagent preparation
           volumes should reflect anticipated usage and reagent stability.
                                      300.1-23

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     14.3   For information about pollution prevention that may be applicable to laboratories
           and research institutions, consult "Less is Better: Laboratory Chemical
           Management for Waste Reduction," available from the American Chemical
           Society's Department of Government Regulations  and Science Policy, 1155 16th
           Street N.W., Washington D.C. 20036,
           (202) 872-4477.

15.   WASTE MANAGEMENT

     15.1   The Environmental Protection Agency requires that laboratory waste
           management practices be conducted consistent with all applicable rules and
           regulations.  Excess reagents, samples and method process wastes should be
           characterized and disposed of in an acceptable  manner. The Agency urges
           laboratories to protect the air, water, and land by minimizing and controlling all
           releases from hoods and bench operations, complying with the letter and spirit of
           any waste discharge permit and regulations, and by complying with all solid and
           hazardous waste regulations, particularly the hazardous waste identification rules
           and land disposal restrictions. For further information on waste management
           consult the "Waste Management Manual for Laboratory Personnel," available
           from the American  Chemical Society at the address listed in Sect. 14.3.

16.   REFERENCES

     1.     "Determination  of Inorganic Disinfection By-Products by Ion Chromatography",
           J. Pfaff, C. Brockhoff.  J. Am. Waterworks Assoc., Vol 82, No. 4, pg 192.

     2.     Standard Methods for the Examination of Water and Wastewater,  Method
           4110B, "Anions by Ion Chromatography", 18th Edition of Standard Methods
           (1992).

     3.     Dionex, System DX500 Operation and Maintenance Manual, Dionex Corp.,
           Sunnyvale, California 94086, 1996.

     4.     Method Detection Limit (MDL) as described in "Trace Analyses for
           Wastewater," J.  Glaser, D. Foerst, G. McKee,  S. Quave, W. Budde,
           Environmental Science and Technology, Vol. 15, Number 12, page 1426,
           December, 1981.

     5.     American Society for Testing and Materials. Test Method for Anions in Water by
           Chemically-Suppressed Ion Chromatography D4327-91. Annual Book of
           Standards, Vol 11.01(1993).

     6.     Code of Federal Regulations 40, Ch. 1, Pt. 136, Appendix B.

     7.     Hautman, D.P. & Bolyard, M. Analysis of Oxyhalide Disinfection By-products
           and other Anions of Interest in Drinking Water by Ion Chromatography. Jour, of
           Chromatog., 602, (1992), 65-74.
                                      300.1-24

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Standard Methods for the Examination of Water and Wastewater, Method 4500-
C1O 2,C " Amperometric Method I" (for the determination of Chlorine Dioxide),
19th Edition of Standard Methods (1995).
                           300.1-25

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17.   TABLES, DIAGRAMS, FLOWCHARTS AND VALIDATION DATA
TABLE 1A.  CHROMATOGRAPHIC CONDITIONS AND METHOD DETECTION
            LIMITS IN REAGENT WATER FOR THE COMMON ANIONS (PART
A).

ANALYTE
Fluoride
Chloride
Nitrite-N
Surrogate: DC A
Bromide
Nitrate-N
ortho-Phosphate-P
Sulfate

PEAK # (1)
1
2
3
4
5
6
7
8

RETENTION TIME
(MIN.)
2.53
4.67
6.01
7.03
8.21
9.84
11.98
13.49
MDL
Fort Cone,
mg/L
0.020
0.020
0.010

0.040
0.010
0.040
0.040
DETERMINATION
Number
of
Replicates
7
7
7

7
7
7
7
DI
MDL
mg/L
0.009
0.004
0.001

0.014
0.008
0.019
0.019
Standard Conditions:

Ion Chromatograph:
Columns :
Detector:
Suppressor:
Eluent:
Eluent Flow:
Sample Loop:
Dionex DX500
Dionex AG9-HC / AS9-HC, 2 mm
Suppressed Conductivity Detector, Dionex CD20
ASRS-I, external source electrolytic mode, 100 mA current
9.0 mM Na2CO3
0.40 mL/min
10 uL
System Backpressure:  2800 psi
Background Conductivity:      22 uS

Recommended method total analysis time:  25 minutes

(1)  See Figure 1
                                   300.1-26

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TABLE IB.   CHROMATOGRAPHIC CONDITIONS AND METHOD
              DETECTION LIMITS IN BOTH REAGENT WATER AND HIGH
              IONIC STRENGTH WATER FOR THE INORGANIC
              DISINFECTION BY-PRODUCTS  (PART B).



ANALYTE

Chlorite
Bromate
Surrogate:
DCA
Bromide
Chlorate



PEAK # (1)

1
2
4

5
6


RETENTION
TIME
(MIN.)
3.63
4.19
7.28

8.48
9.28
MDL DETERMINATION
Fort
Cone,
ug/L

2.00
2.00


2.00
2.00
Number
of
Replicates

7
7


7
7
DI
MDL
ug/L

0.89
1.44


1.44
1.31
fflW(2)
MDL
ug/L

0.45
1.28


2.51
0.78
Standard Conditions:

Ion Chromatograph:
Columns :
Detector:
Suppressor:
Eluent:
Eluent Flow:
Sample Loop:
Dionex DX500
Dionex AG9-HC / AS9-HC, 2 mm
Suppressed Conductivity Detector, Dionex CD20
ASRS-I, external source electrolytic mode, 100 mA current
9.0 mM Na2CO3
0.40 mL/min
50 uL
System Backpressure:   2800 psi
Background Conductivity:      22 uS

Recommended method total analysis time:  25 minutes

(1)  See Figure 2 and 3

(2)   HIW indicates High Ionic Strength Water which is a simulated drinking water prepared
     from reagent water and fortified with chloride at 100 mg/L, carbonate at 100 mg/L,
     nitrate at 10.0 mg/L as nitrogen, phosphate at 10.0 mg/L as phosphorous, and sulfate at
     100 mg/L.
                                    300.1-27

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TABLE 1C.    CHROMATOGRAPHIC CONDITIONS AND METHOD
              DETECTION LIMITS IN REAGENT WATER FOR THE
              INORGANIC DISINFECTION BY-PRODUCTS USING AN
              ALTERNATE 4 mm AS9-HC COLUMN (PART B).


ANALYTE
Chlorite
Bromate
Surrogate:
DCA
Bromide
Chlorate


PEAK#
1
2
4
5
6


RETENTION
TIME
(MIN.)
4.43
5.10
8.82
10.11
10.94
MDL
Fort
Cone,
ug/L
2.00
2.00

2.00
2.00
DETERMINATION
Number
of
Replicates
7
7

7
7
DI
MDL
ug/L
1.44
1.32

0.98
2.55
Standard Conditions:

Ion Chromatograph:
Columns :
Detector:
Suppressor:
Eluent:
Eluent Flow:
Sample Loop:
Dionex DX500
Dionex AG9-HC / AS9-HC, 4 mm
Suppressed Conductivity Detector, Dionex CD20
ASRS-I, external source electrolytic mode, 300 mA current
9.0 mM Na2CO3
1.25 mL/min
200 uL
System Backpressure:  1900 psi
Background Conductivity:      21 uS

Recommended method total analysis time:  25 minutes
                                   300.1-28

-------
TABLE 2A. SINGLE-OPERATOR PRECISION AND RECOVERY FOR THE
COMMON
ANIONS (PART A).
UNFORT FORT #
MATRIX CONC OF MEAN MEAN
ANALYTE MATRIX CONC., mg/L REPLC mg/L %REC SD(n-l)
mg/L
Fluoride



Chloride



Nitrite-N



Bromide



Nitrate-N



Phosphate-P



Sulfate



Surrogate:



RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW

-------
   TABLE 2B.   SINGLE-OPERATOR PRECISION AND RECOVERY FOR THE
                 INORGANIC DISINFECTION BY-PRODUCTS (PART B).
ANALYTE MATRIX
Chlorite RW

HIW

SW

GW

C1W

CDW

O3W

Bromate RW

HIW

SW

GW

C1W

CDW

O3W

UNFORT
CONC.
ug/L

-------
TABLE 2B. SINGLE-OPERATOR PRECISION AND RECOVERY FOR THE INORGANIC
          DISINFECTION BY-PRODUCTS (PART B) (contd.).
UNFORT
CONC.
ANALYTE MATRIX ug/L




























Bromide RW

HIW

SW

GW

C1W

CDW

O3W

Chlorate RW

HIW

SW

GW

C1W

CDW

O3W


-------
TABLE 2B.    SINGLE-OPERATOR PRECISION AND RECOVERY FOR THE INORGANIC
               DISINFECTION BY-PRODUCTS (PART B)(contd.).
ANALYTE
Surrogate: DC A
(see NOTE below)












MATRIX
RW

HIW

SW

GW

C1W

CDW

O3W

FORT
CONC
mg/L
5.00

5.00

5.00

5.00

5.00

5.00

5.00

#
OF
REPLC
9

9

9

9

9

9

9

MEAN
mg/L
5.11
4.98
5.00
4.96
4.95
4.99
5.12
5.13
5.15
5.13
5.01
5.04
4.99
5.11
MEAN
%REC
102
99.5
100
99.2
98.9
99.8
102
103
103
103
100
101
99.8
101
SD(n-l)
0.93
0.69
0.79
1.76
0.70
1.60
0.50
0.50
1.73
1.12
1.02
1.08
0.70
0.53
%RSD
0.91
0.69
0.79
1.78
0.7
1.61
0.49
0.49
1.68
1.09
1.02
1.07
0.7
0.52
 RW = Reagent Water
HIW = High Ionic strength Water
      [see note (2) in Table IB]
SW= Surface Water
                        GW =  Groundwater
                        C1W =  Chlorinated drinking water
                       CDW = Chlorine dioxide treated drinking water
                       O3W = Ozonated drinking water
NOTE:
The surrogate DCA was fortified at 5 mg/L but due to concerns about measuring trace
concentrations of bromide with such high concentration of the neighboring surrogate
peak, the recommended fortified concentration for the surrogate has been reduced to
1.00 mg/L.
                                          300.1-32

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TABLE 3A.    STABILITY STUDY RESULTS FOR THE COMMON ANIONS (PART A).
ANALYTE Preservative
Fluoride None



Chloride None



Nitrite-N None



Bromide None



Nitrate-N None



Phosphate-P None



Sulfate None



Matrix
RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW
RW
SW
GW
CDW
UNFORT
CONC.
mg/L

-------
      TABLE 3B STABILITY STUDY RESULTS FOR THE INORGANIC DISINFECTION BY-
                PRODUCTS (PARTB).

ANALYTE Preservative
Chlorite None






Chlorite EDA






Bromate None






Bromate EDA







Matrix
RW
HIW
SW
GW
C1W
CDW
O3W
RW
HIW
SW
GW
C1W
CDW
O3W
RW
HIW
SW
GW
C1W
CDW
O3W
RW
HIW
SW
GW
C1W
CDW
O3W
UNFORT
CONC.
ug/L

-------
TABLE 3B.  STABILITY STUDY RESULTS FOR THE INORGANIC DISINFECTION
BY-PRODUCTS (PART B)(contd.)

ANALYTE Preservative
Bromide None






Bromide EDA






Chlorate None






Chlorate EDA







Matrix
RW
HIW
SW
GW
C1W
CDW
O3W
RW
HIW
SW
GW
C1W
CDW
O3W
RW
HIW
SW
GW
C1W
CDW
O3W
RW
HIW
SW
GW
C1W
CDW
O3W
UNFORT
CONC.
ug/L

-------
Peak Ret. Time
I^A 1 2-53
DU 2 4.67
 i






|jS




-2 -]
3 6.01
2 4 7.03






1



5 8.21
6 9.84
7 11.98
8 13.49
* The surrogate,
Anion
Fluoride
Chloride
Nitrite-N
Dichloroacetate*
Bromide
Nitrate-N
O- Phosphate- P
Sulfate
dichloroacetate (DCA)
mg/L
3.20
32.0
3.20
5.00
3.20
3.20
8.00
36.8
,is shown at the
recommended concentration of 5.00 mg/L for Part A.

3
.
f[ 4 5
8
A
6 7 A
A /vj\



k. 	

i i i i i i i i i i i i i i i i i i
I i i i I i i i
0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.
Minutes

1
00

Figure 1. Chromatogram showing separation of the Part A common anions on the AS9-HC column.
         See Table 1A for analysis conditions.
                                              300.1-36

-------
                                                 Peak Ret. Time
      MS
    0
I  I   I
.00
                                                        3.63
                                                        4.19
                                                        4.83
                                                        7.28
                                                        8.48
                                                        9.28
                                                 Anion
                                                 Chlorite
                                                 Bromate
                                                 Chloride
                                                 Dichloroacetate*
                                                 Bromide
                                                 Chlorate
                                                                      ug/L
                                                                      500
                                                                      500
                                                                      Bkgrd
                                                                      5.00 mg/L
                                                                      500
                                                                      500
                                   The surrogate, dichloroacetate (DCA) ,is shown at
                                   5.00 mg/L, the initial concentration used during
                                   method development. The recommended DCA
                                   concentration has been reduced to 1 .00 mg/L for
                                   Part B.
              I   I
I  I   I
I
I  I   I
\  \\
i  i   i
                              4.00    6.00    8.00   10.00
                                           Minutes
                                                 12.00    14.00
Figure 2 Chromatogram showing separation of the Part B inorganic DBFs and bromide on the AS9-HC
        column. See Table IB for analysis conditions.
                                             300.1-37

-------
    0.3
     uS
   0
                \   \  \

             0.00
>.oo
                           Peak
                             1
                             2
                             3
                             4
                             5
                             6
                         Ret. Time
                         3.63
                         4.19
                         4.83
                         7.28
                         8.48
                         9.28
 Anion
 Chlorite
 Bromate
 Chloride
 Dichloroacetate*
 Bromide
 Chlorate
 ug/L
2.00
2.00
Bkgrd
1.00 mg/L
2.00
2.00
                                                   The surrogate, dichloroacetate (DCA) is shown at
                                                   the recommended concentration of 1 .OOmg/L for
                                                   PartB.
    i  i  i     i  i  i     i  i  i     r

4.00     6.00     8.00    10.00
            Minutes
\     \  \  \     \

12.00   14.00
Figure 3. Chromatogram of the inorganic DBFs and bromide (Part B) during the MDL determination in
        reagent water. See Table IB for analysis conditions.
                                             300.1-38

-------
      1
      0
                                 8
                                                                     3.
                                                                     4.1
                                                                     4.
                                                                     7.
                                                                     8.
                                                                     9.
                                                                     D.3
                                                                    ,2.5
                                                                    14.0
                              63
                               9
                              8i3
                               8
                              48
                               8
           Anion
           Chlorite
           Bromate
           Chloride
           DCA*
           Bromide
           Chlorate
         Nitrate-N
         Phosphate-P
         Sulfate
                ug/L
                1DD
                5.0D
                1DOmg/L
                5.DD mg/L
              20.D
                1DD
              10.0 mg/L
              10.0 mg/L
              100 mg/L
                                                                The surrogate, dichloroacetate (DCA) ,is
                                                                shown\at 5.00 mg/L, the initial concentration
                                                                used during method development. The
                                                                recommended DCA concentration has been
                                                                reduced to 1.00 mg/L for Part B.
                                             i   i  r
              i   i  r
i  i  r
i  i  r
             0.00
6.00    8.00   10.00   12.00   14.00
    Minutes
Figure 4. Chromatogram of the inorganic DBFs and bromide (Part B) in high ionic strength water (HIW). See
         Table IB for analysis conditions.
                                               300.1-39

-------