SEPA
United States
Environmental Protection
Agency
 www.epa.gov
  Method 617: The Determination of
  Organohalide Pesticides and
  PCBs in Municipal and Industrial
  Waste water

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            Method 617
      The Determination of
Organohalide Pesticides and
    PCBs in Municipal and
     Industrial Wastewater

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                               Method 617
 The Determination of Organohalide Pesticides and PCBs in Municipal
                        and Industrial  Wastewater
1.     SCOPE AND APPLICATION

1.1    This method covers the determination of certain organohalide pesticides and PCBs. The
      following parameters can be determined by this method:

                  Parameter
                  Aldrin
                  a-BHC
                  B-BHC
                  5-BHC
                  Y-BHC
                  Captan
                  Carbophenothion
                  Chlordane
                  4,4'-DDD
                  4,4'-DDE
                  4,4'-DDT
                  Dichloran
                  Dicofol
                  Dieldrin
                  Endosulfan I
                  Endosulfan II
                  Endosulfan sulfate
                  Endrin
                  Endrin aldehyde
                  Heptachlor
                  Heptachlor epoxide
                  Isodrin
                  Methoxychlor
                  Mirex
                  PCNB
                  Perthane
                  Strobane
                  Toxaphene
                  Trifluralin
                  PCB-1016
                  PCB-1221
                  PCB-1232
                  PCB-1242
                  PCB-1248
                  PCB-1254
                  PCB-1260
Storet No.
39330
39337
39338
39259
39340
39640
—
39350
39310
39320
39300
—
39780
39380
34356
34361
34351
39390
34366
39410
39420
39430
39480
39755
39029
39034
—
39400
39030
34671
39488
39492
39496
39500
39504
39508
CAS No.
309-00-2
319-84-6
319-85-7
319-86-8
58-89-9
133-06-2
786-19-6
57-74-9
72-54-8
72-55-9
50-29-3
99-30-9
115-32-2
60-57-1
959-98-8
33213-65-9
1031-07-8
72-20-8
7421-93-4
76-44-8
1024-57-3
465-73-6
72-43-5
2385-85-5
82-68-8
72-56-0
8001-50-1
8001-35-2
1582-09-8
12674-11-2
11104-28-2
11141-16-5
53469-21-9
12672-29-6
11097-69-1
11096-82-5

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Method 617
1.2     This  is a gas chromatographic (GC) method applicable to the determination of the
       compounds listed above in  industrial and municipal discharges  as  provided under
       40 CFR 136.1.  Any modification of this method beyond those expressly permitted shall
       be considered a major modification subject to application and approval of alternative test
       procedures under 40 CFR 136.4 and 136.5.

1.3     The method detection limit (MDL, defined in Section 15) for many of the parameters are
       listed in Table 1.  The MDL for a specific wastewater may differ from those listed,
       depending upon  the nature of interferences in the sample matrix.

1.4     The sample extraction and concentration steps in this method are essentially the same as
       in Method 614.   Thus, a single sample may be extracted to measure the parameters
       included  in the  scope of both of these methods.   When cleanup  is required,  the
       concentration  levels must be  high enough to permit selecting aliquots, as necessary, in
       order to apply appropriate cleanup procedures.  Under gas chromatography, the analyst
       is allowed the   latitude to  select chromatographic  conditions appropriate  for  the
       simultaneous  measurement of combinations of these parameters  (see Section 12).

1.5     This  method is restricted to use by or under the supervision of analysts experienced in
       the use of gas chromatography and in the interpretation of gas chromatograms.  Each
       analyst must  demonstrate  the ability to  generate acceptable results with this  method
       using the procedure described in Section 8.2.

1.6     When this method is used to analyze unfamiliar samples for any or all of the compounds
       above,  compound  identifications  should  be  supported  by  at least  one additional
       qualitative technique.   This  method describes  analytical conditions for a second  gas
       chromatographic column that can be used to  confirm measurements made with the
       primary column.  Section 14 provides gas chromatograph/mass spectrometer (GC/MS)
       criteria appropriate for the qualitative confirmation of compound identifications.

2.     SUMMARY OF METHOD

2.1     A measured volume of sample, approximately 1 L,  is extracted with  15% methylene
       chloride in hexane using a separatory funnel.  The extract is dried and concentrated to
       a volume of 10 mL or less.  Gas chromatographic conditions are described which permit
       the separation and measurement of the compounds in the extract by  electron capture gas
       chromatography.

2.2     Method 617 represents an  editorial revision of two previously promulgated U.S. EPA
       methods for pesticides and for PCBs.1 While complete method  validation  data is not
       presented herein, the method has been in widespread use since  its promulgation, and
       represents the state of the art for the analysis of such materials.

2.3     This  method  provides  selected  cleanup  procedures to  aid in  the elimination  of
       interferences which may be encountered.

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                                                                                Method 617
3.     INTERFERENCES

3.1     Method interferences may be caused by contaminants in solvents, reagents, glassware,
       and other sample processing apparatus that lead to discrete artifacts or elevated baselines
       in gas chromatograms. All reagents and apparatus must be routinely demonstrated to
       be free from interferences under the conditions of the analysis by running laboratory
       reagent blanks as described in Section 8.5.

       3.1.1   Glassware must be scrupulously cleaned.2 Clean all glassware as soon as possible
              after use by thoroughly rinsing with the  last  solvent used  in  it.  Follow by
              washing with hot water and detergent and thorough rinsing with tap and reagent
              water.  Drain dry, and heat  in an oven or muffle furnace at 400°C for 15 to 30
              minutes. Do not heat volumetric ware. Thermally stable materials, such as PCBs,
              may not be eliminated by this treatment.  Thorough rinsing  with acetone  and
              pesticide-quality hexane may be substituted for the heating.  After drying  and
              cooling, seal  and store glassware  in  a clean environment to prevent  any
              accumulation of dust or other  contaminants.   Store inverted or capped with
              aluminum foil.

       3.1.2   The use of high-purity reagents  and solvents  helps to minimize interference
              problems.  Purification of solvents by distillation in all-glass systems may be
              required.

3.2     Interferences by phthalate esters can  pose a major problem in pesticide analysis when the
       EC detector is  used.  These compounds generally appear in the chromatogram as large
       late-eluting peaks, especially in the 15% and 50% fractions from the Florisil column
       cleanup.   Common flexible plastics contain varying  amounts of phthalates.   These
       phthalates  are easily  extracted or leached  from such materials  during laboratory
       operations. Cross-contamination of clean glassware occurs  when plastics are handled
       during  extraction  steps,  especially  when  solvent-wetted  surfaces  are  handled.
       Interferences from phthalates can be minimized by avoiding the use of plastics  in the
       laboratory. Exhaustive cleanup of reagents and glassware may be required to eliminate
       background phthalate contamination.3'4  The interferences from phthalate esters can be
       avoided by using a microcoulometric or electrolytic conductivity detector.

3.3     Matrix interferences may be caused by contaminants that are coextracted  from the
       sample. The extent of matrix interferences will vary considerably from source to source,
       depending upon  the nature and  diversity of the industrial complex or municipality
       sampled.  The  cleanup procedure in Section 11 can be used to overcome many of these
       interferences, but unique samples may require additional cleanup approaches to achieve
       the MDL listed in Table 1.

4.     SAFETY

4.1     The toxicity or  carcinogenicity of each reagent used in this method has not been precisely
       defined; however, each chemical compound must be treated as a potential health hazard.
       From this viewpoint, exposure to these chemicals must be reduced to the lowest possible
       level by whatever means available. The laboratory is responsible  for maintaining a
       current awareness file of OSHA regulations regarding the safe handling of the chemicals

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Method 617
       specified in this method. A reference file of material data handling sheets should also
       be made available  to  all personnel involved in the chemical analysis.   Additional
       references to laboratory safety are available and have been identified  5 7  for  the
       information of the analyst.

4.2     The following parameters covered by this method have been tentatively classified as
       known or suspected human or mammalian carcinogens:  aldrin, benzene hexachlorides,
       chlordane, heptachlor, PCNB, PCBs, and toxaphene.  Primary standards of these toxic
       materials should be prepared in a hood.

5.     APPARATUS AND MATERIALS

5.1     Sampling equipment, for discrete or composite sampling.

       5.1.1   Grab-sample bottle:  Amber borosilicate or flint glass, 1-L or 1-quart volume,
              fitted with screw-caps lined with TFE-fluorocarbon.  Aluminum foil may  be
              substituted  for TFE if the sample  is not corrosive.   If amber bottles  are  not
              available, protect samples from light.  The container and cap  liner  must  be
              washed, rinsed with acetone or methylene chloride,  and dried before  use to
              minimize contamination.

       5.1.2   Automatic sampler (optional):  Must incorporate glass  sample containers for the
              collection of a minimum of 250 mL.  Sample containers must be kept refrigerated
              at 4°C  and protected from light during  compositing.  If the sampler  uses a
              peristaltic pump, a minimum length of compressible silicone rubber tubing may
              be used. Before use, however, the compressible tubing must be thoroughly rinsed
              with methanol, followed by repeated rinsings with reagent water to minimize the
              potential for  contamination of the sample.  An integrating flow meter is required
              to collect flow-proportional composites.

5.2     Glassware.   (All  specifications are  suggested.   Catalog numbers  are included  for
       illustration only.)

       5.2.1   Separatory funnel:   125-mL, 1000-mL, and 2000-mL, with  TFE-fluorocarbon
              stopcock, ground-glass or TFE stopper.

       5.2.2   Drying column:   Chromatographic column 400  mm  long by 19 mm ID with
              coarse-fritted disc.

       5.2.3   Chromatographic column:  400 mm long by 19 mm ID  with coarse-fritted disc at
              bottom and TFE-fluorocarbon stopcock  (Kontes K-420540-0224 or equivalent).

       5.2.4   Concentrator tube, Kuderna-Danish:  10-mL, graduated (Kontes K-570050-1025 or
              equivalent).  Calibration must be checked at the volumes employed in the test.
              Ground-glass stopper is used to prevent evaporation of extracts.

       5.2.5   Evaporative   flask,  Kuderna-Danish:    500-mL  (Kontes   K-570001-0500   or
              equivalent).  Attach to concentrator tube with springs.

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                                                                                Method 617
       5.2.6   Snyder column,  Kuderna-Danish:  three-ball macro (Kontes K-503000-0121  or
              equivalent).

       5.2.7   Vials:  Amber glass, 10- to 15-mL capacity with TFE-fluorocarbon-lined screw-cap.

5.3     Boiling chips:  Approximately 10/40 mesh.  Heat at 400°C for 30 minutes or perform a
       Soxhlet extraction with methylene chloride.

5.4     Water bath:  Heated, with concentric ring cover, capable of temperature control (±2°C).
       The bath should be used in a hood.

5.5     Balance:  Analytical, capable of accurately weighing to the nearest 0.0001 g.

5.6     Shaker:  Laboratory, reciprocal action.

5.7     Gas chromatograph: Analytical system complete with gas chromatograph suitable for
       on-column injection and all required accessories including syringes, analytical columns,
       gases, detector, and strip-chart recorder. A data system is recommended for measuring
       peak areas.

       5.7.1   Column 1:  180 cm long by 4 mm ID  glass, packed with 1.5% SP-2250/1.95% SP-
              2401 on Supelcoport (100/120 mesh) or equivalent.  This column was used to
              develop the method performance statements in Section 15.  Alternative columns
              may be used in accordance with the  provisions described in Section 12.1.

       5.6.2   Column 2:  180 cm long by 4 mm ID glass, packed with 3% OV-1 on Supelcoport
              (100/120  mesh) or equivalent.

       5.6.3   Detector:  Electron capture. This detector has proven effective in the analysis of
              wastewaters for the parameters listed in the scope and was used to develop the
              method performance statements in Section 15.  Alternative detectors, including
              a  mass spectrometer, may be used in accordance with the provisions described
              in Section 12.1.

6.     REAGENTS

6.1     Reagent  water:  Reagent water is defined  as a water in which an interferant is not
       observed at the method detection limit of each parameter of interest.

6.2     Acetone,  hexane, isooctane, methylene chloride: Pesticide-quality or equivalent.

6.3     Ethyl ether:  Nanograde, redistilled in glass  if necessary. Must be free of peroxides as
       indicated by EM  Quant test strips  (available from Scientific Products Co., Cat. No. PI 126-
       8, and other suppliers).  Procedures recommended for removal of peroxides are provided
       with the  test strips.  After cleanup, 20 mL ethyl alcohol preservative must be added to
       each liter of ether.

6.4     Acetonitrile, hexane-saturated:  Mix pesticide-quality acetonitrile with an excess of hexane
       until equilibrium is established.

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Method 617
6.5     Sodium sulfate:  ACS, granular, anhydrous.   Heat in a shallow tray at  400°C for a
       minimum of four hours to remove phthalates and other interfering organic substances.
       Alternatively, heat 16 hours at 450 to  500°C in a shallow tray or Soxhlet  extract with
       methylene chloride for 48 hours.

6.6     Sodium chloride solution, saturated: Prepare saturated solution of NaCl in reagent water
       and extract with hexane to  remove impurities.

6.7     Sodium hydroxide solution  (ION):  Dissolve 40 g ACS grade NaOH in reagent water and
       dilute to 100 mL.

6.8     Sulfuric acid solution (1 + 1):  Slowly add 50 mL H2SO4 (sp. gr. 1.84) to 50 mL of reagent
       water.

6.9     Mercury:  Triple-distill.

6.10    Florisil:  PR grade (60/100 mesh).  Purchase activated at 675°C and store in dark in glass
       container with  ground-glass stopper or foil-lined screw-cap. Before use, activate each
       batch at least 16 hours at 130°C in a foil-covered glass container.

6.11    Stock standard  solutions  (1.00 ug/uL):  Stock standard solutions may be prepared from
       pure standard materials or  purchased as certified solutions.

       6.11.1  Prepare  stock standard solutions by accurately weighing approximately 0.0100 g
              of pure  material.  Dissolve the material in pesticide-quality isooctane and dilute
              to  volume in a 10-mL volumetric flask.  Larger volumes may be  used  at the
              convenience of the analyst. If compound purity is certified at 96% or greater, the
              weight may be used without correction to calculate the concentration of the stock
              standard.   Commercially-prepared stock  standards  may be used  at any
              concentration if they are  certified by the manufacturer or by an independent
              source.

       6.11.2  Transfer the stock standard solutions into  TFE-fluorocarbon-sealed screw-cap
              vials.  Store at 4°C and protect from light. Frequently check stock  standard
              solutions for signs of  degradation or  evaporation,  especially just  prior  to
              preparing calibration standards from them.

       6.11.3  Stock standard solutions must be replaced after 6 months, or sooner if comparison
              with check standards indicates a problem.

7.     CALIBRATION

7.1     Establish gas chromatographic operating parameters equivalent to those  indicated in
       Table 1.  The gas chromatographic system may be calibrated using either  the external
       standard technique (Section 7.2) or the internal standard technique (Section 7.3).

7.2     External standard calibration procedure.

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                                                                                Method 617
       7.2.1   For each parameter of interest, prepare calibration standards at a minimum of
              three concentration levels by adding accurately measured volumes of one or more
              stock standards to a volumetric flask and diluting to volume with isooctane.  One
              of the external standards should be representative of a concentration near, but
              above, the method detection limit.  The other concentrations should correspond
              to the range of concentrations expected in the sample concentrates or should
              define the working range of the detector.

       7.2.2   Using injections of 1 to 5 uL of each calibration standard, tabulate peak height or
              area responses against the mass injected.  The results can be used to prepare a
              calibration curve for each parameter.  Alternatively, the ratio of the response to
              the  mass injected, defined as the calibration factor (CF), may be calculated for
              each parameter at each standard concentration. If the relative standard deviation
              of the calibration factor is  less than  10%  over the working range, the average
              calibration factor can be used in place of a calibration curve.

       7.2.3   The working calibration curve or  calibration  factor must be verified on  each
              working shift by the measurement of one or more calibration standards. If the
              response for any parameter varies from the predicted  response  by more  than
              ±10%, the test must be repeated using a fresh calibration  standard.  Alternatively,
              a new calibration curve or calibration factor must be prepared for that parameter.

7.3     Internal standard calibration procedure: To use this approach, the analyst must select
       one or more internal standards similar  in  analytical  behavior to the compounds of
       interest.  The analyst must further demonstrate that the measurement of the internal
       standard is not affected by method or matrix interferences.  Due to these  limitations, no
       internal standard applicable to all samples can be suggested.

       7.3.1   Prepare calibration standards at a minimum of three concentration  levels for  each
              parameter of interest by adding volumes of one or  more stock standards  to a
              volumetric flask. To each calibration standard, add a known constant amount of
              one or more internal standards, and dilute to volume with isooctane. One of the
              standards should be representative of a concentration near, but above, the method
              detection limit.  The other concentrations should correspond to the  range of
              concentrations expected in the sample concentrates, or should define the working
              range of the detector.

       7.3.2   Using injections of 1-5 uL of each calibration standard, tabulate the peak height
              or  area responses against the  concentration  for  each compound and internal
              standard.  Calculate response factors (RF)  for each compound as follows:

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Method 617
                                       Equation 1


                                    RF  =  —	
              where
              As  = Response for the parameter to be measured
              Asi = Response for the internal standard
              Cls = Concentration of the internal standard, in ug/L
              Cs  = Concentration of the parameter to be measured, in ug/L
              If the RF value over the working range  is constant,  less than  10% relative
              standard deviation, the RF can be assumed to be invariant and the average RF
              may  be  used for calculations.  Alternatively,  the results may be used to  plot a
              calibration curve of response ratios, As/Ais against RF.

       7.3.3   The working calibration curve or RF must be verified on each working shift by
              the measurement of one or more calibration standards.  If the response for any
              parameter varies from the predicted response by more than ±10%, the test must
              be repeated using a fresh calibration standard.  Alternatively, a new calibration
              curve must be prepared for that  compound.

7.4     The cleanup procedure in Section 11 utilizes Florisil  chromatography.  Florisil from
       different batches or sources may vary in adsorptive capacity.  To standardize the amount
       of Florisil which is used, the use of the lauric acid value is suggested.  This procedure8
       determines the  adsorption from hexane  solution of lauric acid, in milligrams, per gram
       of Florisil. The amount of Florisil to  be  used for each column is calculated by dividing
       this factor into  110 and multiplying by 20 g.

7.5     Before using any cleanup procedure, the  analyst must process a  series of calibration
       standards through  the procedure to validate  elution patterns and the absence of
       interference  from the reagents.

7.6     The multipeak materials included in this method present a special  calibration problem.
       Recommended  procedures for calibration,  separation and measurement of PCBs is
       discussed in detail in the previous edition of this method.1  Illustrated methods for the
       calibration  and measurement  of chlordane  and strobane/toxaphene  are available
       elsewhere.9

8.     QUALITY CONTROL

8.1     Each  laboratory using this  method  is  required to  operate a formal quality control
       program. The minimum requirements of this program consist of an  initial demonstration
       of laboratory capability and the analysis of spiked samples as a continuing check on

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                                                                                Method 617
       performance. The laboratory is required to maintain performance records to define the
       quality of data that is generated.

       8.1.1   Before performing any  analyses, the analyst must demonstrate  the ability to
              generate acceptable accuracy and precision with this method.  This ability  is
              established as described in Section 8.2.

       8.1.2   In recognition of the rapid advances occurring in chromatography, the analyst is
              permitted  certain  options 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 Section 8.2.

       8.1.3   The laboratory must spike and  analyze a  minimum of  10% of all samples to
              monitor continuing laboratory performance.  This procedure is  described in
              Section 8.4.

8.2     To establish the ability to generate acceptable accuracy and precision, the analyst must
       perform the following operations.

       8.2.1   Select a representative spike concentration for each compound to be measured.
              Using stock standards, prepare  a quality control check  sample concentrate in
              acetone, 1000 times more concentrated than the selected concentrations.

       8.2.2   Using a pipette, add 1.00 mL of the check sample concentrate to each  of a
              minimum  of  four 1000-mL  aliquots of  reagent  water.   A representative
              wastewater may be used in place of the reagent water, but one or more additional
              aliquots must be analyzed to determine background levels,  and the spike level
              must exceed twice the background  level for the test to be valid.  Analyze the
              aliquots according  to the method beginning in Section 10.

       8.2.3   Calculate the average percent recovery  (R), and the standard deviation  of the
              percent recovery  (s), for the results. Wastewater background  corrections must be
              made before R and s calculations are performed.

       8.2.4   Table 2 provides  single-operator recovery and precision for  many of the
              organohalide pesticides. Similar results should be expected  from  reagent water
              for all parameters  listed in this  method.  Compare these results to the values
              calculated  in Section 8.2.3.  If the data are not comparable,  review potential
              problem areas and repeat the test.

8.3     The analyst must  calculate method performance criteria and define  the performance of
       the laboratory for each spike concentration  and parameter being measured.

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Method 617
       8.3.1  Calculate upper and lower control limits for method performance as follows:

             Upper Control Limit (UCL) = R + 3s
             Lower Control Limit (LCL) = R - 3s

             where R and s are calculated as in Section 8.2.3. The UCL and LCL can be used
             to construct control charts10 that are useful in observing trends in performance.

       8.3.2  The laboratory must develop  and maintain separate accuracy statements of
             laboratory performance for wastewater samples. An accuracy statement for the
             method is defined as R ± s. The accuracy statement should be developed by the
             analysis of four aliquots of wastewater as described in Section 8.2.2, followed by
             the calculation of R and s. Alternatively, the analyst may use four wastewater
             data points gathered through the requirement for continuing quality control in
             Section 8.4.  The accuracy statements should be updated regularly.10

8.4     The laboratory is required to collect in duplicate a portion of their samples to monitor
       spike recoveries. The frequency  of spiked sample analysis must be at least 10% of all
       samples or one spiked sample per month, whichever is  greater.  One aliquot of the
       sample must be spiked and analyzed as described in Section 8.2.  If the recovery for a
       particular parameter does not fall within the control limits for method performance, the
       results reported for that parameter in all samples processed as part of the same set must
       be qualified as described in Section 13.3.  The laboratory should monitor the frequency
       of data so qualified to ensure that it remains at or below 5%.

8.5     Before processing any samples, the analyst must demonstrate through the analysis of a
       1-L  aliquot of reagent water that all  glassware and reagent interferences are under
       control.  Each time  a set of samples is extracted or there is a change in reagents, a
       laboratory reagent  blank must  be  processed  as a  safeguard  against  laboratory
       contamination.

8.6     It is recommended that the laboratory adopt additional quality assurance practices for
       use with this method. The specific practices that are most productive depend upon the
       needs of the laboratory and the nature of the samples. Field duplicates may be analyzed
       to monitor the precision of the  sampling technique.  When doubt  exists  over  the
       identification  of a peak on the chromatogram, confirmatory techniques such as  gas
       chromatography with a  dissimilar  column,  specific  element  detector,  or mass
       spectrometer must be used.  Whenever possible, the laboratory should perform analysis
       of quality control materials and participate in relevant performance evaluation studies.

9.     SAMPLE COLLECTION, PRESERVATION, AND HANDLING

9.1     Grab samples must be collected in glass containers.  Conventional sampling practices11
       should be followed;  however, the bottle must not be  prerinsed with sample before
       collection. Composite samples should be  collected in refrigerated  glass containers in
       accordance with the requirements of the program. Automatic sampling equipment must
       be as free as possible of plastic and other potential sources of contamination.

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                                                                               Method 617
9.2     The samples must  be  iced  or  refrigerated  at 4°C  from the time of collection until
       extraction.  Chemical preservatives should not be used in the field unless more than 24
       hours will elapse before delivery to the laboratory.  If the samples will not be extracted
       within 48 hours of collection, the sample should be adjusted to a pH range of 6.0 to 8.0
       with sodium hydroxide or sulfuric acid. Record the volume of acid or base used.

9.3     All samples must be extracted within 7 days and completely analyzed within 40 days of
       extraction.

10.    SAMPLE EXTRACTION

10.1    Mark the water meniscus on the side of the sample bottle for later determination of
       sample volume. Pour the entire sample into a 2-L separatory  funnel.

10.2    Add 60 mL 15% (v/v) methylene chloride in hexane to the sample bottle, seal, and shake
       30 seconds to rinse the inner walls. Transfer the solvent to the separatory funnel and
       extract the sample by shaking the funnel for  2 minutes with periodic venting to release
       excess pressure.  Allow  the organic  layer  to separate from the  water phase for a
       minimum of 10 minutes.  If the emulsion interface between layers is more than one-third
       the  volume of the solvent layer, the analyst must  employ mechanical  techniques to
       complete the phase separation.  The optimum technique depends upon the sample,  but
       may include stirring, filtration of the emulsion through glass wool,  centrifugation, or
       other physical methods. Drain the aqueous phase into a  1000-mL Erlenmeyer flask and
       collect the  extract in a 250-mL Erlenmeyer  flask.   Return the  aqueous phase to  the
       separatory funnel.

10.3    Add a second 60-mL volume of 15% methylene chloride  in hexane to the sample bottle
       and repeat the extraction procedure a second time, combining the extracts in the 250-mL
       Erlenmeyer flask.  Perform a third extraction in the same manner.

10.4    Assemble a Kuderna-Danish  (K-D) concentrator by attaching a 10-mL concentrator tube
       to a 500- mL evaporative  flask.  Other concentration  devices or techniques may be used
       in place of the K-D if the  requirements of Section 8.2 are met.

10.5    Pour  the  combined extract  through  a drying  column containing  about 10  cm of
       anhydrous sodium sulfate, and collect the extract in the K-D concentrator. Rinse  the
       Erlenmeyer flask and column with 20 to 30 mL of hexane to complete the quantitative
       transfer.

10.6    Add one or two clean boiling  chips to the evaporative flask and attach  a three-ball
       Snyder column. Prewet the  Snyder column by adding about  1 mL methylene chloride
       to the top.  Place the  K-D  apparatus  on a hot water  bath,  80 to 85°C,  so  that  the
       concentrator tube  is partially immersed in  the hot water, and the entire lower  rounded
       surface of the flask is bathed  with hot vapor.   Adjust the vertical position  of  the
       apparatus and the water temperature as required to complete the concentration in 15 to
       20 minutes. At the proper rate of distillation,  the balls of the column will actively chatter
       but  the chambers will not flood with condensed solvent.  When the apparent volume of
       liquid reaches 1 mL, remove the  K-D apparatus and allow it to drain and cool for at least
       10 minutes.

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Method 617
10.7    Remove the Snyder column and rinse the flask and its lower joint into the concentrator
       tube with 1 to 2 mL of hexane and adjust the volume to 10 mL.  A 5-mL syringe is
       recommended for this operation.  Stopper the  concentrator tube and  store refrigerated
       if further processing will not be performed immediately.  If the extracts will be stored
       longer than 2 days, they should be transferred  to PTFE-sealed screw-cap bottles. If the
       sample extract requires no further cleanup, proceed with gas chromatographic analysis.
       If the sample  requires cleanup, proceed to Section 11.

10.8    Determine the original sample volume by refilling the sample bottle to the mark and
       transferring the water to a 1000-mL graduated cylinder.  Record the sample volume to
       the nearest 5 mL.

11.    CLEANUP AND SEPARATION

11.1    Cleanup procedures may not be necessary for a relatively  clean sample  matrix.  The
       cleanup procedure recommended  in this method has been used  for the analysis of
       various industrial and municipal effluents.  If particular circumstances demand the use
       of an alternative cleanup procedure, the analyst must determine the elution profile and
       demonstrate that the recovery of each compound of interest for the cleanup procedure
       is no less than 85%.

11.2    Acetonitrile partition:  The following acetonitrile partitioning procedure may be used to
       isolate fats and oils from the sample extracts.  This procedure is applicable to all of the
       parameters in this method except mirex.

       11.2.1 Quantitatively transfer the previously concentrated extract to a 125-mL separatory
             funnel with enough hexane to bring the final volume to  15  mL.  Extract  the
             sample four times by shaking vigorously for 1 minute with 30-mL portions of
             hexane-saturated acetonitrile.

       11.2.2 Combine and transfer the acetonitrile phases to a 1-L separatory funnel and add
             650 mL of reagent water and 40 mL of saturated sodium chloride solution.  Mix
             thoroughly for  30 to 45 seconds. Extract with two 100-mL portions of hexane by
             vigorously shaking for 15 seconds.

       11.2.3 Combine the hexane extracts in a 1-L separatory funnel and wash with two 100-
             mL portions of reagent water.  Discard the water layer and pour the hexane layer
             through a drying column containing 7 to 10 cm of anhydrous sodium sulfate into
             a  500-mL  K-D  flask equipped with a 10-mL concentrator  tube.  Rinse  the
             separatory funnel and column with three 10-mL portions of hexane.

       11.2.4 Concentrate the extracts to 6 to 10 mL in  the K-D as directed in  Section 10.6.
             Adjust the extract volume to 10 mL with hexane.

       11.2.5 Analyze by gas chromatography unless a need for further cleanup is indicated.

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                                                                                Method 617
11.3    Florisil column cleanup:  The following Florisil column cleanup  procedure has been
       demonstrated to be applicable to most of the organochlorine pesticides and PCBs listed
       in Table 3.  It should also be applicable to the cleanup of extracts  for PCNB, strobane,
       and trifluralin.

       11.3.1 Add a weight of Florisil (nominally 20 g), predetermined by calibration (Sections
             7.4 and  7.5), to a chromatographic column.  Settle the Florisil by tapping the
             column. Add anhydrous sodium sulfate to the top of the Florisil to form a layer
             1 to 2 cm deep.  Add 60 mL of hexane to wet and rinse the sodium sulfate and
             Florisil.  Just prior to exposure of the sodium sulfate to air, stop the elution of the
             hexane by closing the  stopcock on the  chromatography column.  Discard the
             eluate.

       11.3.2 Adjust the sample extract volume  to 10 mL with hexane and transfer  it from the
             K-D concentrator tube to the Florisil column.  Rinse the tube  twice with 1 to 2 mL
             hexane,  adding each rinse to the column.

       11.3.3 Place a 500-mL K-D flask and clean concentrator tube under the chromatography
             column. Drain the column into the flask until the sodium sulfate layer is nearly
             exposed.  Elute  the  column with 200 mL  of 6% (v/v)  ethyl ether in hexane
             (Fraction 1) using a drip rate of about 5 mL/min.  Remove the K-D flask and set
             aside for later concentration.  Elute the column again, using  200 mL of 15% (v/v)
             ethyl ether in  hexane  (Fraction 2), into a second K-D  flask.  Perform a third
             elution using 200 mL  of 50% (v/v)  ethyl  ether  in hexane (Fraction 3)  into a
             separate K-D flask. The elution patterns for the pesticides and PCBs are shown
             in Table 3.

       11.3.4 Concentrate the  eluates by standard  K-D techniques (Section 10.6), using the
             water bath at about 85°C.  Adjust final volume to 10 mL with hexane.  Analyze
             by gas chromatography.

11.4    Removal of sulfur: Elemental sulfur will elute in  Fraction 1 of the Florisil cleanup
       procedure.  If a large  amount of sulfur is present  in the extract, it may elute  in all
       fractions.  If so,  each fraction must be  further treated to remove the sulfur.   This
       procedure cannot be used with heptachlor, endosulfans, or endrin  aldehyde.

       11.4.1 Pipette  1.00 mL of the concentrated extract into a clean concentrator tube or a vial
             with a TFE-fluorocarbon seal. Add 1 to  3 drops of mercury and seal.

       11.4.2 Agitate the contents of the vial for 15 to 30 seconds.

       11.4.3 Place the vial in an upright position on a reciprocal laboratory shaker and shake
             for up to 2 hours.

       11.4.4 If the  mercury  appears shiny after this treatment, analyze the extract by gas
             chromatography.  If the mercury is black, decant the extract into a clean vial and
             repeat the cleanup with fresh mercury.

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Method 617
12.    GAS CHROMATOGRAPHY

12.1    Table 1 summarizes the recommended operating conditions for the gas chromatograph.
       Included in this table are estimated retention times and method detection limits that can
       be achieved by this method.  Other packed columns, chromatographic conditions, or
       detectors may be used if the requirements of Section 8.2 are  met.   Capillary (open-
       tubular) columns may also be used if the relative standard deviations of responses for
       replicate injections are demonstrated to be less than 6% and the requirements of Section
       8.2 are  met.

12.2    Calibrate the system daily as described in Section 7.

12.3    If the internal standard approach is being used, add the internal standard to sample
       extracts immediately before injection into the instrument.  Mix thoroughly.

12.4    Inject 1 to 5 uL of the sample extract using the solvent-flush technique.12  Record the
       volume injected to the nearest 0.05 uL, and the resulting peak size in area or peak height
       units. An automated system that consistently injects a constant volume of extract may
       also be  used.  Multipeak materials present a special analytical problem beyond the scope
       of this discussion. Illustrated procedures for calibration and measurement are available
       for PCBs1 and pesticides.9

12.5    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 a compound.   However, the experience of the analyst
       should  weigh heavily in the interpretation of chromatograms.

12.6    If the response for the peak exceeds the working range of the system, dilute the extract
       and reanalyze.

12.7    If the measurement of the peak response is prevented by the presence of interferences,
       further cleanup is required.

13.    CALCULATIONS

13.1    Determine the concentration of individual compounds in the sample.

       13.1.1  If the external standard calibration procedure is used, calculate  the amount of
              material injected from the peak response using the calibration curve or calibration
              factor in Section 7.2.2.  The  concentration in  the  sample can  be calculated as
              follows:

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                                                                               Method 617
                                       Equation 2

                                                       (V)
                            Concentration, \ig/L -
             where
             A  = Amount of material injected, in ng
             V,  = Volume of extract injected, in uL
             Vt  = Volume of total extract, in uL
             V,  = Volume of water extracted, in ml
                                                   (V) (V)
       13.1.2 If the  internal  standard  calibration procedure  was  used,  calculate the
             concentration in the sample using the response factor (RF) determined in Section
             7.3.2 as follows:
                                       Equation 3


                         Concentration, \ig/L -
                                                (At) (RF)
             where
             As  = Response for parameter to be measured
             Als  = Response for the internal standard
             Is   = Amount of internal standard added to each extract, in ug
             V0  = Volume of water extracted, in L
13.2    Report results in micrograms per liter without correction for recovery data.  When
       duplicate and spiked samples are analyzed, report all data obtained with the sample
       results.

13.3    For samples processed as part of a set where the laboratory spiked sample recovery falls
       outside of the control limits in Section 8.3, data for  the  affected parameters must be
       labeled as suspect.

14.    GC/MS  CONFIRMATION

14.1    It  is recommended  that  GC/MS techniques  be  judiciously employed  to support
       qualitative compound identifications made with this  method.  The mass spectrometer
       should be capable of scanning the mass range from 35 amu to a mass 50 amu above the
       molecular weight of the compound.  The instrument must be capable of scanning the
       mass range at a rate to produce at least 5 scans per peak but not to exceed 7 per scan

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Method 617
       utilizing a 70 V (nominal) electron energy in the electron impact ionization mode. A
       GC-to-MS interface constructed of all glass or glass-lined materials is recommended. A
       computer  system should be interfaced  to  the mass  spectrometer that allows the
       continuous acquisition and storage on machine-readable  media of all mass spectra
       obtained throughout the duration of the chromatographic program.

14.2    Gas chromatographic columns and conditions should be selected for optimum separation
       and performance. The conditions selected must be compatible with standard GC/MS
       operating practices.  Chromatographic tailing factors of less than 5.0 must be achieved.13
14.3    At the beginning of each day that confirmatory analyses are to be performed, the GC/MS
       system must be  checked  to  see that all  decafluorotriphenyl phosphine (DFTPP)
       performance criteria are achieved.14

14.4    To confirm an identification of a compound, the background-corrected mass spectrum
       of the compound must be obtained from the sample extract and compared with a mass
       spectrum from a stock or calibration standard analyzed under the same chromatographic
       conditions.  It is recommended that at least 25 ng of material be injected into the GC/MS.
       The criteria below must be met for qualitative confirmation.

       14.4.1 All ions that are present above  10% relative abundance in the mass spectrum of
             the standard must be present in the mass spectrum of the sample with agreement
             to ±10%.  For example, if the relative abundance of an ion is 30% in the mass
             spectrum of the standard, the allowable limits  for the relative abundance of that
             ion in the mass spectrum for the sample would be 20 to 40%.

       14.4.2 The retention time of the compound in the sample must be within 6  seconds of
             the same compound in the standard solution.

       14.4.3 Compounds that have very similar mass spectra can be explicitly identified by
             GC/MS only on the basis of retention time data.

14.5    Where available, chemical  ionization  mass spectra may be employed to  aid  in the
       qualitative identification process.

14.6    Should these MS procedures fail to provide satisfactory results, additional steps may be
       taken before reanalysis. These may include the use of alternate packed or capillary GC
       columns or additional cleanup (Section 11).

15.    METHOD PERFORMANCE

15.1    The  method  detection limit (MDL) is defined as the minimum  concentration of a
       substance that can be measured and reported with 99% confidence that the value is above
       zero.15  The MDL concentrations listed in Table 1 were obtained using reagent watet".
15.2    In a  single laboratory, Susquehanna University, using spiked tap water samples, the
       average recoveries presented in Table  2 were obtained. The standard deviation of the
       percent recovery is also included in Table 2.16

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                                                                              Method 617
                                    References

1.      "Methods  for Benzidine, Chlorinated Organic  Compounds,  Pentachlorophenol and
       Pesticides  in  Water  and  Wastewater,"  U.S.   Environmental  Protection  Agency,
       Environmental Monitoring and Support Laboratory, Cincinnati, Ohio, September 1978.

2.      ASTM Annual Book of Standards, Part 31, D3694, "Standard Practice  for Preparation of
       Sample Containers and for Preservation," American Society for Testing and Materials,
       Philadelphia, PA, p. 679, 1980.

3.      Giam, D.S., Chan, H.S., and Nef, G.S.  "Sensitive Method for Determination of Phthalate
       Ester Plasticizers in Open-Ocean Biota Samples," Analytical Chemistry, 47, 2225 (1975).

4.      Giam, C.S. and Chan, H.S. "Control of Blanks in the Analysis  of Phthalates in Air and
       Ocean Biota Samples," National Bureau of Standards (U.S.), Special Publication 442, pp.
       701-708, 1976.

5.      "Carcinogens-Working with  Carcinogens,"  Department  of Health, Education, and
       Welfare, Public Health  Service,  Center for Disease Control, National Institute for
       Occupational Safety and Health, Publication No. 77-206, August 1977.

6.      "OSHA Safety and Health Standards, General Industry" (29 CFR 1910), Occupational
       Safety and Health Administration, OSHA 2206 (Revised, January  1976).

7.      "Safety in Academic Chemistry Laboratories," American Chemical Society Publication,
       Committee on Chemical  Safety, 3rd Edition, 1979.

8.      ASTM Annual Book of Standards, Part  31, D3086, Appendix  X3, "Standardization of
       Florisil Column by Weight Adjustment Based on Adsorption of Laurie Acid," American
       Society for Testing and Materials, Philadelphia, PA, p. 765, 1980.

9.      "Pesticide Analytical Manual Volume 1," U.S. Department of Health and Human Services,
       Food and Drug Administration.

10.     "Handbook for Analytical Quality Control in Water and Wastewater Laboratories," EPA-
       600/4-79-019,  U. S. Environmental Protection Agency, Environmental Monitoring and
       Support Laboratory-Cincinnati, Ohio, March 1979.

11.     ASTM  Annual Book of Standards,  Part 31,  D3370, "Standard Practice for Sampling
       Water," American Society for Testing and Materials, Philadelphia, PA, p. 76, 1980.

12.     Burke,  J. A.  "Gas Chromatography for Pesticide Residue Analysis;  Some Practical
       Aspects," Journal of the Association of Official Analytical Chemists, 48, 1037 (1965).

13.     McNair, H.M. and  Bonelli,  E.  J.   "Basic Chromatography,"   Consolidated  Printing,
       Berkeley, California, p. 52, 1969.

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Method 617
14.     Eichelberger, J.W., Harris, L.E., and Budde, W.L. "Reference Compound to Calibrate Ion
       Abundance  Measurement  in Gas  Chromatography-Mass Spectrometry,"  Analytical
       Chemistry, 47, 995 (1975).

15.     Glaser, J.A. et al.  "Trace Analysis for Wastewaters," Environmental Science & Technology,
       15, 1426 (1981).

16.     McGrath, T. F.  "Recovery Studies of Pesticides From Surface and Drinking Waters," Final
       Report for U.S. EPA Grant R804294, Environmental Monitoring and Support Laboratory,
       Cincinnati, Ohio 45268.

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                                                                              Method 617
Table 1.
             Gas Chromotagraphy of Pesticides and PCBs
                                     Retention Time (min)
            Parameter
            Aldrin
            a-BHC
            (3-BHC
            5-BHC
            Y-BHC
            Cap tan
            Carbophenothion
            4,4'-DDD
            4,4'-DDE
            4,4'-DDT
            Dichloran
            Dicofol
            Dieldrin
            Endosulfan I
            Endosulfan II
            Endosulfan sulfate
            Endrin
            Endrin aldehyde
            Heptachlor
            Heptachlor epoxide
            Isodrin
            Methoxychlor
            Mirex
            PCNB
            Trifluralin
Column 1
2.40
1.35
1.90
2.15
1.70
6.22
10.9
7.83
5.13
9.40
1.85
2.86
5.45
4.50
8.00
14.22
6.55
11.82
2.00
3.50
3.00
18.20
14.60
1.63
0.94
Column 2
4.10
1.82
1.97
2.20
2.13
5.00
10.90
9.08
7.15
11.75
2.01
4.59
7.23
6.20
8.28
10.70
8.19
9.30
3.35
5.00
4.83
26.60
15.50
2.01
1.35
                                                                Method
                                                               Detection
                                                                 Limit
                                                                    0.009
                                                                    0.004
                                                                  ND
                                                                  ND
                                                                    0.002
                                                                  ND
                                                                  ND
                                                                    0.012
                                                                    0.004
                                                                    0.032
                                                                  ND
                                                                  ND
                                                                    0.011
                                                                    0.11
                                                                    0.17
                                                                  ND
                                                                  ND
                                                                  ND
                                                                    0.004
                                                                    0.003
                                                                  ND
                                                                    0.176
                                                                    0.015
                                                                    0.002
                                                                    0.013
*For multipeak materials, see Figures 2 through 10 for chromatographic conditions and retention
patterns.

ND = Not Determined

Column 1 conditions:  Supelcoport (100/120 mesh) coated with 1.5% SP-2250/1.95% SP-2401 in
a glass column 1.8 m long by 4 mm  ID with 95% argon/5% methane carrier gas at a flow rate
of 60 mL/min.  Column temperature: isothermal at 200°C.  An electron capture detector was
used with this column to determine  the MDL.

Column 2 conditions:  Supelcoport  (100/120 mesh) coated with  3% OV-1 packed in a glass
column 1.8 m long  by 4 mm ID with 95% argon/5% methane carrier gas at a flow rate of
60 mL/min.  Column temperature:  isothermal at 200°C.

-------
Method 61 7
Table 2. Single-Operator Accuracy and Precision for Tap Water
Parameter
Aldrin
5-BHC
Y-BHC
4,4'-DDD
4,4'-DDE
4,4'-DDT
Dieldrin
Endosulfan I
Endosulfan II
Heptachlor
Heptachlor epoxide
Methoxychlor
Mirex
PCNB
Trifluralin
Average
Percent
Recovery
78.1
95.3
95.1
94.4
89.8
91.0
98.2
101.0
92.9
84.4
93.7
96.6
89.1
82.6
94.3
Standard
Deviation
(%)
5.4
8.9
7.2
5.0
3.7
4.5
4.9
7.6
4.8
6.4
3.9
6.7
4.8
6.2
10.5
Spike
Range
(Vg/L)
0.03-3.0
0.01-1.0
0.01-1.0
0.08-8.0
0.05-5.0
0.2-20
0.06-6.0
0.05-5.0
0.09-9.0
0.02-2.0
0.03-3.0
0.6-60
0.2-20
0.01-1.0
0.03-3.0
Number
of
Analyses
21
21
21
21
21
21
21
21
21
21
21
21
21
21
21

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                                                                             Method 617
Table 3.      Distribution and Recovery of Chlorinated Pesticides and PCBs Using Florisil
             Column Chromatography
                                             Percent Recovery by Fraction
        Parameter
        Aldrin
        a-BHC
        (3-BHC
        5-BHC
        Y-BHC
        Captan
        Carbofenthion
        Chlordane
        4,4'-DDD
        4,4'-DDE
        4,4'-DDT
        Dicofol
        Dieldrin
        Endosulfan I
        Endosulfan II
        Endosulfan sulfate
        Endrin
        Endrin aldehyde
        Heptachlor
        Heptachlor epoxide
        Isodrin
        Methoxychlor
        Mirex
        Perthane
        Toxaphene
        PCB-1016
        PCB-1221
        PCB-1232
        PCB-1242
        PCB-1248
        PCB-1254
        PCB-1260
No. 1
   100
   100
    97
    98
   100
     +
   100
   100
    99
    98
   100
     +
     0
    37
     0
     0
     4
     0
   100
   100
   100
   100
   100
   100
    96
    97
    97
    95
    97
   103
    90
    95
No. 2
 No. 3
   100
    64
     7
     0
    96
    68
 91
106
 26
+ = Compound occurs in both 6% and 15% fractions.

Florisil eluate composition by fraction:
  Fraction 1 = 200 mL of 65% ethyl ether in hexane
  Fraction 2 = 200 mL of 15% ethyl ether in hexane
  Fraction 3 = 200 mL of 50% ethyl ether in hexane

-------
Method 617
         Column: 1.5%SP-2250+
                  1.95% SP-2401 on Supelcoport
         Temperature:  200°C
         Detector: Electron Capture
             \     I
                 4.0
i     i
    8.0
i     r
    12.0
  i     r
16.0
                        Retention Time (minutes)
                                                                        A52-OO2-39A
            Figure 1.    Gas Chromatogram of Pesticides

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                                                                    Method 617
     Column:  1.5% SP-2250+
              1.95% SP-2401 on Supelcoport
     Temperature: 200°C
     Detector:  ElectronCapture
   II
          I     I     I     I     1     I     I
         4.0        8.0       12.0       16.0
          Retention Time (minutes)
                                                         A52-002-40A
Figure 2.  Gas Chromatogram of Chlordane

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Method 617
                                        Column: 1.5%SP-2250+
                                                1.95% SP-2401 on Supelcoport
                                        Temperature: 200°C
                                        Detector: Electron Capture
              —l—
            0  2.0
—I	T
 10.0
 i     r
14.0
6.0
18.0
22.0
                                                                     26.0
                                Retention Time (minutes)
                                                                                A52-002-41A
                    Figure 3.    Gas Chromatogram of Toxaphene

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                                                                     Method 617
 Column: 1.5% SP-2250+ 1.95% SP-2401 on Supelcoport
 Temperature. 160°C
 Detector:  Electron Capture
  —i	r
0   2.0
—I	!	1	1	1	i	1	
 10.0      14.0     18.0      22.0
6.0
                Retention Time (minutes)
                                                               A52-002-42A
    Figure 4.    Gas Chromatogram of PCB-1016

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Method 617
                Column: 1.5% SP-2250+ 1.95% SP-2401 on Supelcoport
                Temperature: 160"C
                Detector: Electron Capture
                              "I     1    I     I	1	1	T
                                  10.0      14.0     18.0
0   2.0
6.0
                                    22.0
                              Retention Time (minutes)
                                                                              A52-002J3A
                   Figure 5.   Gas Chromatogram of PCB-1221

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                                                                         Method 617
Column: 1.5% SP-2250+1.95% SP-2401 on Supelcoport
Temperature: 160°C
Detector:  Electron Capture
2.0
6.0
10.0
14.0
18.0
22.0
22.0
                   Retention Time (minutes)
                                                                  AS2-002-44A
      Figure 6.   Gas Chromatogram of PCB-1232

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Method 617
                Column: 1.5% SP-2250 + 1.95% SP-2401
                        on Supelcoport
                Temperature: 160°C.
                Detector: Electron Capture
           0   2.0
6.0
10.0
14.0
18.0
22.0
                              Retention Time (minutes)
                                                                              A52-002-45A
                    Figure 7.  Gas Chromatogram of PCB-1242

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                                                                          Method 617
     Column: 1.5% SP-2250 + 1.95% SP-2401 on
             Supelcoport
     Temperature: 160°C.
     Detector:  Electron Capture
0   2.0
6.0
1    1—
    10.0
~~i     r
 14.0
                                       18.0
                               22.0
                                            26.0
                     Retention Time (minutes)
                                                                   AS2-002-46A
             Figure 8.   Gas Chromatogram of PCB-1248

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Method 617
                   Column: 1.5% SP-2250+ 1.95% SP-2401 on Supelcoport
                   Temperature: 200°C
                   Detector:  Electron Capture
                   2.0
6.0
10.0
14.0
18.0
                                                                       22.0
                                   Retention Time (minutes)
                                                                                   AS2-002-47A
                       Figure 9.    Gas Chromatogram of PCB-1254

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                                                                          Method 617
Column: 1.5% SP-2250+ 1.95% SP-2401 on Supelcoport
Temperature: 200°C
Detector:  Electron Capture
     i    i     i    i     i    i     i     I
0   2.0       6.0       10.0      14.0
18.0
  i    i
22.0
                                                        26.0
                     Retention Time (minutes)
                                                                   AS2-002-48A
             Figure 10.  Gas Chromatogram of PCB-1260

-------