EPA-821-R-01-011
                                        January 2001
                   METHOD 200.9

TRACE ELEMENTS IN WATER, SOLIDS, AND BIOSOLIDS BY
STABILIZED TEMPERATURE GRAPHITE FURNACE ATOMIC
            ABSORPTION SPECTROMETRY
                    Revision 3.0
                    January 2001
         U.S.  Environmental Protection Agency
           Office of Science and Technology
                  Ariel Rios Building
            1200 Pennsylvania Avenue, N.W.
                Washington, D.C. 20460

-------
Method 200.9
                                   Acknowledgments

Revision 3.0 of Method 200.9 was prepared under the direction of William A. Telliard of the U.S.
Environmental Protection Agencies (EPA's) Office of Water (OW), Engineering and Analysis Division
(EAD) in collaboration with Ted Martin, of EPA's Office of Research and Development's National
Exposure Research Laboratory in Cincinnati, Ohio. The method was prepared under EPA Contract 68-
C3-0337 by DynCorp Consulting Services Division with assistance from Quality Works, Inc. and
Westover Scientific, Inc.

The following personnel at the EPA Office of Research and Development's National Exposure Research
Laboratory in Cincinnati, Ohio, are gratefully acknowledged for the development of the analytical
procedures described in this method:

J.T.  Creed, T.D. Martin, L.B. Lobring, and J.W. O'Dell - Method 200.9, Revision 1.2 (1991)

J.T.  Creed, T.D. Martin, and J.W. O'Dell -  Method 200.9, Revision 2.2 (1994)


                                        Disclaimer

This draft method has been reviewed and approved for publication by the Analytical Methods Staff within
the Engineering and Analysis Division of the U.S. Environmental Protection Agency. Mention of trade
names or commercial products does not constitute endorsement or recommendation for use.  EPA plans
further validation of this draft method.  The method may be revised following validation to reflect results of
the study. This method version contains minor editorial changes to the October 2000 version.

EPA welcomes suggestions for improvement of this method.  Suggestions and questions concerning this
method or its application should be addressed to:

W.A. Telliard
Analytical Methods Staff (4303)
Office of Science and Technology
U.S. Environmental Protection Agency
Ariel Rios Building
1200 Pennsylvania Avenue, N.W.
Washington, D.C. 20460
Phone: 202/260-7134
Fax:  202/260-7185
                                                                                 Draft, January 2001

-------
                                                                                        Method 200.9
     Note: This method is performance based. The laboratory is permitted to omit any step or modify
     any procedure provided that all performance requirements in this method are met. The laboratory
     may not omit any quality control analyses.  The terms "must," "shall," and "may not" define
     procedures required for producing reliable data for producing reliable results. The terms "may"
     and "should" indicate optional steps that may be modified or omitted if the laboratory can
     demonstrate that the modified method produces results equivalent or superior to results produced
     by this method.
Draft, January 2001

-------
                                 Method 200.9

 Trace Elements in Water, Solids, and Biosolids by Stabilized
                                 Temperature
       Graphite Furnace Atomic Absorption Spectrometry


1.0   Scope and Application

1.1   This method provides procedures for the determination of dissolved and total recoverable elements
      by graphite furnace atomic absorption spectrometry (GFAA) in ground water, surface water,
      drinking water, storm runoff, and industrial and domestic wastewater (Reference 1).  This method
      is also applicable to the determination of total recoverable elements in sediment, biosolids
      (municipal sewage sludge), and soil. This method is applicable to the following analytes:
Analyte
Aluminum
Antimony
Arsenic
Beryllium
Cadmium
Chromium
Cobalt
Copper
Iron
Lead
Manganese
Nickel
Selenium
Silver
Thallium
Tin

(Al)
(Sb)
(As)
(Be)
(Cd)
(Cr)
(Co)
(Cu)
(Fe)
(Pb)
(Mn)
(Ni)
(Se)
(Ag)
(Tl)
(Sn)
Chemical Abstract Services
Registry Number (CASRN)
7429-90-5
7440-36-0
7440-38-2
7440-41-7
7440-43-9
7440-47-3
7440-48-4
7440-50-8
7439-89-6
7439-92-1
7439-96-5
7440-02-0
7782-49-2
7440-22-4
7440-28-0
7440-31-5
1.2   To confirm approval of this method for use in compliance monitoring programs [e.g., Clean Water
      Act (NPDES) or Safe Drinking Water Act (SDWA)], consult both the appropriate sections of the
      Code of Federal Regulation (40 CFRPart 136 Table IB for NPDES, and Part 141  141.23 for
      drinking water), and the latest Federal Register announcements.


1.3   Dissolved analytes can be determined in aqueous samples after suitable filtration and acid
      preservation.


1.4   With the exception of silver, where this method is approved for the determination of certain metal
      and metalloid contaminants in drinking water, samples may be analyzed by direct injection into the


Draft, January 2001                                                                        1

-------
Method 200.9
        furnace without acid digestion if the sample has been properly preserved with acid, has turbidity of
        <1 NTU at the time of analysis, and is analyzed using the appropriate method matrix modifiers.
        This total recoverable determination procedure is referred to as "direct analysis".  However, in the
        determination of some primary drinking water metal contaminants, such as arsenic and thallium,
        preconcentration of the sample may be required prior to analysis in order to meet drinking water
        acceptance performance criteria (Section  11.5.8).

1.5     For the determination of total recoverable analytes in aqueous and solid samples, a
        digestion/extraction is required prior to analysis when the elements are not in solution (e.g., soil,
        biosolids, sediment and aqueous samples that may contain particulate and suspended solids).
        Aqueous samples containing total suspended solids > 1% (w/v) should be extracted as a solid
        sample.

1.6     Silver is only slightly soluble in the presence of chloride unless there is a sufficient chloride
        concentration to form the soluble chloride complex.  Therefore, low recoveries of silver may occur
        in samples, fortified sample matrices and even fortified blanks if determined as a  dissolved analyte
        or by "direct analysis" where the sample has not been processed using the total recoverable
        digestion. For this reason it is recommended that samples be digested prior to the determination of
        silver. The total recoverable sample digestion procedure given in this method is suitable for the
        determination of silver in aqueous samples containing concentrations up to 0.1 mg/L. For the
        analysis of wastewater samples containing higher concentrations of silver, succeeding smaller
        volume, well-mixed aliquots should be prepared until the analysis solution contains <0.1 mg/L
        silver. The extract of solid samples containing concentrations of silver >50 mg/kg should be
        treated in a similar manner.

1.7     Method detection limits (MDLs; 40 CFR  136, Appendix B) and minimum levels  (MLs) when no
        interferences are present will be determined for this method through a validation study (Table 1).
        The ML for each analyte can be calculated by multiplying the MDL by 3.18 and  rounding to the
        nearest (2, 5, or 10 X 10") where n is an integer.

1.8     The sensitivity and limited linear dynamic range (LDR) of GFAA often requires dilution of a
        sample prior to analysis.  The magnitude of the dilution as well as the cleanliness of the labware
        used to perform the dilution can dramatically influence the quality of the analytical results.
        Therefore, samples requiring large dilutions (>50:1) should be analyzed by another approved test
        procedure having a larger LDR or having less sensitivity than GFAA.

1.9     Users of the method data should state the  data quality objectives prior to analysis. Users of the
        method must document and have on file the required initial demonstration performance data
        described in Section 9.2 prior to using the method for analysis.

1.10   This method is accompanied by Appendix A: Total Solids in Solid and Semi-Solid Matrices.  The
        procedure in Appendix A should be followed for sludge and solid samples analyzed under Sections
        11.3 and 11.4.

1.11   This method will be validated in biosolids for those analytes regulated under 40 CFR Part 503
        only.  It is believed to be applicable for the analysis of biosolids for all analytes listed in Section
        1.1.
                                                                                    Draft, January 2001

-------
                                                                                       Method 200.9
2.0   Summary of Method

2.1    An aliquot of a well-mixed, homogeneous sample is accurately weighed or measured for sample
       processing.  For total recoverable analysis of a solid or aqueous sample containing undissolved
       material, analytes are first solubilized by gentle refluxing with nitric and hydrochloric acids. For
       total recoverable analysis of a sludge sample, analytes are first solubilized by gentle refluxing with
       nitric and hydrochloric acids and hydrogen peroxide. After cooling, the sample is made up to
       volume, mixed, and centrifuged or allowed to settle overnight prior to analysis. For the
       determination of dissolved analytes in a filtered aqueous sample aliquot, or for the "direct analysis"
       total recoverable determination of analytes where sample turbidity is <1 NTU, the sample  is made
       ready for analysis by addition of nitric acid, and then diluted to a predetermined volume and mixed
       before analysis.

2.2    The analytes listed in this method are determined by stabilized temperature platform graphite
       furnace atomic absorption (STPGFAA). In STPGFAA, an aliquot of the sample and the matrix
       modifier are first pipetted onto the instrument platform,  a device which permits delayed
       atomization. The furnace chamber is then purged with a continuous flow of a premixed gas (95%
       argon - 5% hydrogen). The sample is allowed to dry at a relatively low temperature (about 120C)
       to avoid spattering.  Once dried, the sample is pretreated in a char or ashing step which is designed
       to minimize matrix interference effects. After the char step, the furnace is allowed to cool prior to
       atomization. The atomization cycle is characterized by  rapid heating of the furnace to a
       temperature where the metal (analyte) is atomized from the pyrolytic graphite surface into a
       stopped gas flow atmosphere of argon containing 5% hydrogen.  (Selenium is determined in an
       atmosphere of high purity argon).  The resulting  atomic cloud absorbs the element-specific atomic
       emission produced by a hollow cathode lamp or an electrodeless  discharge lamp (EDL). Following
       analysis, the furnace is subjected to a clean out period of high temperature and continuous argon
       flow. Because the resulting absorbance usually has a nonspecific component associated with the
       actual analyte absorbance, a correction is required to subtract background absorbance from the
       total signal.  In the absence of interferences, background corrected absorbance is directly related to
       the concentration of the analyte. Interferences relating to STPGFAA (Section 4.0) must be
       recognized and corrected.  Suppressions or enhancements of instrument response caused by the
       sample matrix must be corrected by the method of standard addition (Section 11.6).

3.0   Definitions

3.1    Biosolids-A solid, semisolid, or liquid residue (sludge) generated during treatment of domestic
       sewage in a treatment works.

3.2    Calibration blank-A volume of reagent water acidified with the same acid matrix as the calibration
       standards. The calibration blank is a zero standard and  is used to auto-zero the AA instrument
       (Section  7.13.1).

3.3    Calibration standard-A solution prepared from the dilution of stock standard solutions (Section
       7.11).  The calibration solutions are used to calibrate instrument response with respect to analyte
       concentration.
Draft, January 2001

-------
Method 200.9
3.4     Calibration verification (CV) solution-A solution of method analytes, used to evaluate
        performance of the instrument system with respect to a defined set of method criteria (Sections
        7.14 and 9.3).

3.5     Dissolved analvte-The concentration of analyte in an aqueous sample that will pass through a 0.45
        (jm membrane filter assembly prior to sample acidification (Section 8.2).

3.6     Field blank-An aliquot of reagent water or other blank matrix that is placed in a sample container
        in the laboratory and treated as a sample in all respects, including shipment to the sampling site,
        exposure to the sampling site conditions, storage, preservation, and all analytical procedures.  The
        purpose of the field blank is to determine if method analytes or other interferences are present in
        the field environment (Section 9.5.2).

3.7     Linear dynamic range (LDR)-The concentration range over which the instrument response to an
        analyte is linear (Section 9.2.3).

3.8     Matrix modifier-A substance added to the graphite furnace along with the sample in order to
        minimize the interference effects by selective volatilization of either analyte or matrix components.

3.9     Matrix spike (MS) and matrix spike duplicate (MSD)-Two aliquots of the same environmental
        sample to which known quantities of the method analytes are added in the laboratory. The MS and
        MSB are analyzed exactly like a sample, and their purpose is to determine whether the  sample
        matrix contributes bias to the analytical results and to indicate precision associated with laboratory
        procedures. The background concentrations of the analytes in the sample matrix must be
        determined in a separate aliquot and the measured values in the MS and MSB corrected for
        background concentrations (Section 9.4).

3.10   Mav-This action, activity, or procedural step is neither required nor prohibited.

3.11   May not-This action, activity, or procedural step is prohibited.

3.12   Method blank-An aliquot of reagent water or other blank matrices that is treated exactly as a
        sample including exposure to all glassware, equipment, solvents, reagents, and internal standards
        that are used with other samples. The method blank is used to determine if method analytes or
        other interferences are present in the laboratory environment, reagents, or apparatus (Sections
        7.13.2 and 9.5.1).

3.13   Method detection limit (MBL)-The minimum concentration of an analyte that can be identified,
        measured, and reported with 99% confidence that the analyte concentration is greater than zero
        (Section 9.2.1 and Table  1). The MBL is determined according to  procedures in 40 CFR Part 136
        Appendix B.

3.14   Minimum level (ML)-The lowest level at which the entire analytical system gives a recognizable
        signal and acceptable calibration point for the analyte.  It is equivalent to the concentration of the
        lowest calibration standard, assuming that all method-specific sample weights, volumes and
        cleanup procedures have been employed.
                                                                                    Draft, January 2001

-------
                                                                                       Method 200.9
3.15  Must-This action, activity, or procedural step is required.

3.16  Ongoing precision and recovery (OPR) standard-The OPR test is used to ensure that the
       laboratory meets performance criteria during the period that samples are analyzed.  It also
       separates laboratory performance from method performance on the sample matrix.  For aqueous
       samples, the OPR solution is an aliquot of method blank to which known quantities of the method
       analytes are added in the laboratory. For solid samples, the use of clean sand, soil or peat moss to
       which known quantities  of the method analytes are added in the laboratory is recommended. The
       OPR is analyzed in the same manner as samples (Section 9.6).

3.17  Shall-This action, activity or procedural step is required.

3.18  Should-This action, activity, or procedural step is suggested but not required.

3.19  Solid sample-For the purpose of this method, a sample taken from material classified as either soil,
       sediment or industrial sludge.

3.20  Standard addition-The addition of a known amount of analyte to the sample in order to determine
       the relative response of the detector to that analyte within the sample matrix. The relative response
       is then used to assess either an operative matrix effect or the sample analyte concentration
       (Sections  9.7 and 11.6).

3.21  Standard stock solution-A concentrated solution containing one or more method analytes prepared
       in the laboratory using assayed reference materials or purchased from a reputable commercial
       source (Section 7.11).

3.22  Total recoverable analvte-The concentration of analyte determined to be in either a solid sample or
       an unfiltered aqueous sample following treatment by refluxing with hot dilute mineral acid(s) as
       specified in the method (Sections 11.2, 11.3, and 11.4).

3.23  Water sample-For the purpose of this method, a sample taken from one of the following sources:
       drinking, surface, ground,  storm runoff, industrial or domestic wastewater.

4.0    Interferences

4.1    Several interference sources may cause inaccuracies in the  determination of trace elements by
       GFAA. These interferences can be classified into three major subdivisions: spectral, matrix, and
       memory.

4.2    Spectral interferences are caused by the resulting absorbance of light from the spectrometer lamp
       by a molecule or atom which is not the analyte of interest.  Spectral interferences also can arise
       from black body radiation  coming from the carbon platform.

       4.2.1   Spectral interferences caused by an element only occur if there is a spectral overlap
               between the wavelength of the interfering element  and the analyte  of interest. Fortunately,
               this type of interference is relatively uncommon in STPGFAA because of the narrow
               atomic line widths associated with this technology. In addition, the use of appropriate

Draft, January 2001                                                                                   5

-------
Method 200.9
               furnace temperature programs and high spectral-purity lamps as light sources can
               minimize this type of interference. However, molecular absorbances can span several
               hundred nanometers producing broadband spectral interferences.  This latter interference is
               far more common in STPGFAA.  Matrix modifiers, selective volatilization, and
               background correctors can all be used to minimize unwanted nonspecific absorbance. The
               nonspecific component of total absorbance can vary considerably among sample types.
               Therefore, the effectiveness of a particular background correction device may vary
               depending on the actual analyte wavelength used as well as the nature and magnitude of
               the interference. The background correction device to be used with this method is not
               specified.  However, whichever one is chosen must provide an analytical condition that is
               not subject to the occurring inter-element spectral interferences of palladium on copper,
               iron on selenium, and aluminum on arsenic.

       4.2.2  Spectral interferences are also caused by the emissions from black body radiation
               produced during the atomization furnace cycle from the carbon surface of the  sample
               platform. The magnitude of this interference can be minimized by proper furnace tube
               alignment and monochromator design. In addition, atomization temperatures which are
               adjusted to adequately volatilize the analyte of interest while minimizing black body
               radiation can reduce unwanted background emission.

4.3    Matrix interferences are caused by sample components which inhibit the formation of free atomic
       analyte during the atomization cycle.

       4.3.1  Matrix interferences can be of a chemical or physical nature.  In this method, the use of a
               delayed atomization device which provides stabilized temperatures is required. These
               devices provide an environment which is more conducive to the formation of free analyte
               atoms and thereby minimize matrix interferences.  This type of interference can be detected
               by analyzing the sample  plus a sample aliquot fortified with a known concentration of the
               analyte. If the determined concentration of the analyte addition is outside a designated
               range, a possible matrix  effect should be suspected (Section 9.4).

       4.3.2  The use of nitric acid is preferred for most GFAA analyses in order to minimize vapor
               state anionic chemical interferences.  However, in this method hydrochloric acid is required
               to maintain stability in solutions containing antimony and silver.  When hydrochloric acid
               is used, the chloride ion vapor state interferences must be reduced using an appropriate
               matrix modifier. In this method, a combination modifier of palladium, magnesium nitrate
               and a hydrogen(5%)-argon(95%) gas mixture is used. The effects and benefits of using
               this modifier are discussed in detail in Reference 2. Listed in Section 4.4 are some
               typically observed effects when using this modifier.

4.4    Specific element interferences.

       4.4.1  Antimony-Antimony suffers from an interference produced by K2SO4 (Reference 3).  In
               the absence of hydrogen in the char cycle (1300C), K2SO4 produces a relatively high (1.2
               abs) background absorbance which can produce a false signal, even with Zeeman
               background correction. However,  this background level can be reduced dramatically (0.1
                                                                                    Draft, January 2001

-------
                                                                                       Method 200.9
               abs) by the use of a hydrogen/argon gas mixture in the char step. This reduction in
               background is strongly influenced by the temperature of the char step.

       NOTE:  The actual furnace temperature may vary from instrument to instrument.  Therefore,
	the optimal furnace temperature should be determined on each instrument.	

       4.4.2  Aluminum-The palladium matrix modifier may have elevated levels of Al which will cause
               elevated blank absorbances.

       4.4.3  Arsenic-HCl present from digestion can influence As sensitivity. Twenty micro liters of a
               1% HC1 solution with Pd used as a modifier results in a 20% loss in sensitivity relative to
               the analyte in a  1% HNO3 solution.  Unfortunately, the use of Pd/Mg/H2 as a modifier
               does not significantly reduce this suppression, and therefore, it is imperative that each
               sample and calibration standard alike contain the same HC1 concentration (Reference 2).

       4.4.4  Cadmium-HCl present from digestion can influence Cd sensitivity.  Twenty micro liters of
               a 1% HC1 solution with Pd used as a modifier results  in an 80% loss in sensitivity relative
               to the analyte in a 1% HNO3 solution. The use of Pd/Mg/H2 as a matrix modifier reduces
               this suppression to less than 10% (Reference 2).

       4.4.5  Lead-HCl present from digestion can influence Pb sensitivity. Twenty micro liters of a
               1% HC1 solution with Pd used as a modifier results in a 75% loss in sensitivity relative to
               the analyte response in a 1% HNO3 solution. The use of Pd/Mg/H2 as a matrix modifier
               reduces this suppression to less than 10%  (Reference 2).

       4.4.6  Selenium-Iron has been shown to suppress Se response with continuum background
               correction (Reference 3). In addition, the use of hydrogen as a purge gas during the dry
               and char steps can cause a suppression in Se response if not purged from the furnace prior
               to atomization.

       4.4.7  Silver-Palladium used in a modifier preparation may have elevated levels of Ag which will
               cause elevated blank absorbances.

       4.4.8  Thallium-HCl present from digestion can influence Tl sensitivity. Twenty micro liters of
               a 1% HC1 solution with Pd used as a modifier results  in a 90% loss in sensitivity relative
               to the analyte in a 1% HNO3 solution. The use of Pd/Mg/H2 as a matrix modifier reduces
               this suppression to less than 10% (Reference 2).

4.5    Memory interferences result from analyzing a sample containing a high concentration of an element
       (typically a high atomization temperature element) which cannot be removed quantitatively in one
       complete set of furnace steps. Analyte which remains in a furnace can produce false positive
       signals on subsequent sample(s). Therefore, an analyst should establish the analyte concentration
       which can be injected into the furnace and adequately removed in one complete set of furnace
       cycles. If this concentration is exceeded, the sample should be diluted and a blank analyzed to
       assure the memory effect has been eliminated before analyzing the diluted sample.
Draft, January 2001

-------
Method 200.9
5.0   Safety

5.1    The toxicity and 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 to these
       compounds should be as low as reasonably achievable. Each laboratory is responsible for
       maintaining a current awareness file of OSHA regulations regarding the safe handling of the
       chemicals specified in this method (References 4-7). A reference file of material data handling
       sheets should also be made available to all personnel involved in the chemical analysis.
       Specifically, concentrated nitric and hydrochloric acids present various hazards to laboratory
       personnel as both are moderately toxic and extremely irritating to skin and mucus membranes. Use
       these reagents in a fume hood whenever possible and if eye or skin contact occurs, flush with large
       volumes of water.  Always wear safety glasses or a shield for eye protection as well as protective
       clothing, and observe proper mixing when working with these reagents.

5.2    The acidification of samples containing reactive materials may result in the release of toxic gases,
       such as cyanides or sulfides. Acidification of samples  should be done in a fume hood.

5.3    All personnel handling environmental samples known to contain or to have been in contact with
       human waste should be immunized against known disease agents.

5.4    During  atomization, the graphite tube emits intense UV radiation.  Suitable eye-safe precautions
       should be taken to protect laboratory personnel.

5.5    The use of the argon/hydrogen gas mixture during the dry and char steps may evolve a
       considerable amount of HC1 gas. Therefore, adequate ventilation is required.

5.6    It is the responsibility of the user of this method to comply with relevant disposal and waste
       regulations. For guidance see Sections 14.0 and 15.0.

6.0   Equipment and Supplies

       NOTE:  The mention of trade names or commercial products in  this method is for illustrative
       purposes only and does not constitute endorsement or recommendation for use by the
       Environmental Protection Agency. Equivalent performance may be achievable using apparatus
       and materials other than those suggested here.  The laboratory is responsible for demonstrating
	equivalent performance.	

6.1    Graphite furnace atomic absorbance spectrophotometer.

       6.1.1  The GFAA spectrometer must be capable of programmed heating of the graphite tube and
               the associated delayed atomization device.  The instrument must be equipped with an
               adequate background correction device capable of removing undesirable nonspecific
               absorbance over the spectral region of interest and provide an analytical condition not
               subject to the occurrence of inter-element spectral overlap  interferences. The furnace
               device must be capable of using an alternate gas supply during specified cycles of the
               analysis. The capability to record relatively fast (<1 s) transient signals and evaluate data
                                                                                   Draft, January 2001

-------
                                                                                        Method 200.9
               on a peak area basis is preferred. In addition, a recirculating refrigeration bath is
               recommended for improved reproducibility of furnace temperatures.

        6.1.2  Single-element hollow cathode lamps or single-element electrodeless discharge lamps along
               with the associated power supplies. Multi-element lamps may be used if they can be
               shown to meet the detection limit and quality control requirements in Section 9.2.

        6.1.3  Argon gas supply (high-purity grade, 99.99%) for use during the atomization of selenium,
               for sheathing the furnace tube when in operation, and during furnace clean out.

        6.1.4  Alternate gas mixture (hydrogen 5%-argon 95%) for use as a continuous gas flow
               environment during the dry and  char furnace cycles. This gas mixture must be used for all
               metals.  Care must be taken when the gas mixture is used for selenium (Section 4.4.6).

        6.1.5  Autosampler capable of adding matrix modifier solutions to the furnace, a single addition
               of analyte, and completing methods of standard additions when required.

6.2     Analytical balance, with capability to measure to 0.1 mg, for use in weighing solids, preparing
        standards, and determining dissolved solids in digests or extracts.

6.3     A temperature adjustable hot plate  capable of maintaining a temperature of 95 C.

6.4     (Optional) A steel cabinet centrifuge with guard bowl, electric timer and brake.

6.5     A gravity convection drying oven with thermostatic control capable of maintaining 180C5C.

6.6     (Optional) An air displacement pipetter  capable of delivering volumes ranging from 100 - 2500
        yL with an assortment of high quality, disposable pipet tips.

6.7     Mortar and pestle, ceramic or nonmetallic material.

6.8     Polypropylene sieve, 5-mesh (4 mm opening).

6.9     Labware-All reusable labware (glass, quartz, polyethylene, PTFE, FEP, etc.) should be
        sufficiently clean for the task objectives.  Several procedures found to provide clean  labware
        include washing with a detergent solution, rinsing with tap water, soaking for four hours or more in
        20% (v/v) HNO3 or a mixture of dilute HNO3 and HC1 (1:2:9), rinsing with reagent water and
        storing clean (Reference  1). Ideally, ground glass surfaces should be avoided to eliminate a
        potential source of random contamination. When this is impractical, particular attention  should be
        given to all ground glass  surfaces during cleaning. Chromic acid cleaning solutions must be
        avoided because chromium is an analyte.

        6.9.1   Glassware-Volumetric flasks, graduated cylinders, funnels and centrifuge tubes (glass
               and/or metal-free plastic).

        6.9.2  Assorted calibrated pipettes.
Draft, January 2001

-------
Method 200.9
       6.9.3  Conical Phillips beakers, 250 mL with 50 mm watch glasses.

       6.9.4  Griffin beakers, 250 mL with 75 mm watch glasses and (optional) 75 mm ribbed watch
               glasses.

       6.9.5  (Optional) PTFE and/or quartz Griffin beakers, 250 mL with PTFE covers.

       6.9.6  Evaporating dishes or high-form crucibles, porcelain, 100 mL capacity.

       6.9.7  Narrow-mouth storage bottles, FEP (fluorinated ethylene propylene) with screw closure,
               125 mL to 1 L capacities.

       6.9.8  One-piece stem FEP wash bottle with screw closure, 125 mL capacity.

7.0   Reagents and Standards

7.1    Reagents may contain  elemental impurities which might affect analytical data. Whenever possible,
       high-purity reagents that conform to the American Chemical Society specifications should be used
       (Reference 8). If the purity of a reagent is in question, analyze for contamination. All acids used
       for this method must be of ultra high-purity grade or equivalent.  Suitable acids are available from
       a number of manufacturers.  Redistilled acids prepared by sub-boiling distillation are acceptable.

7.2    Hydrochloric acid, concentrated (sp.gr. 1.19)-HC1.

       7.2.1  Hydrochloric acid (1:1)- Add 500 mL concentrated HC1 to 400 mL reagent water and
               dilute to 1 L.

       7.2.2  Hydrochloric acid (1:4) - Add 200 mL concentrated HC1 to 400 mL reagent water and
               dilute to 1 L.

7.3    Nitric acid, concentrated (sp.gr.  1.41)-HNO3.

       7.3.1  Nitric acid (1:  l)-Add 500 mL concentrated HNO3 to 400 mL reagent water and dilute to 1
               L.

       7.3.2  Nitric acid (l:5)-Add 50 mL concentrated HNO3 to 250 mL reagent water.

       7.3.3  Nitric acid (l:9)-Add 10 mL concentrated HNO3 to 90 mL reagent water.

7.4    Reagent water-All references to water in this method refer to ASTM Type I grade water
       (Reference 9).

7.5    Ammonium hydroxide, concentrated (sp.  gr.  0.902).

7.6    Tartaric acid, ACS reagent grade.
10                                                                                Draft, January 2001

-------
                                                                                       Method 200.9
7.7    Matrix modifier-Dissolve 300 mg palladium (Pd) powder in cone. HNO3 (1 mL of HNO3, adding
       0.1 mL of concentrated HC1 if necessary).  Dissolve 200 mg of Mg(NO3)2 in reagent water. Pour
       the two solutions together and dilute to 100 mL with reagent water.

       NOTE:  It is recommended that the matrix modifier be analyzed separately in order to assess
	the contribution of the modifier to the absorbance of calibration and reagent blank solutions.

7.8    Hydrogen peroxide, 30%, stabilized certified reagent grade.

7.9    Clean sand or soil-All references to  clean sand or soil in this method refer to sand or soil certified
       to be free of the analytes of interest at or above their MDLs or to contain those analytes at certified
       levels.

7.10  Peat moss-All references to peat moss in this method refer to sphagnum peat moss certified to be
       free of arsenic, cadmium, copper, lead, nickel, and selenium at or above their MDLs or to contain
       those analytes at certified levels.

7.11  Standard stock solutions may be purchased or prepared from ultra-high purity grade chemicals
       (99.99 - 99.999% pure).  All compounds must be dried for one hour at 105 C, unless otherwise
       specified. It is recommended that stock solutions be stored in FEP bottles. Replace stock
       standards when succeeding dilutions for preparation of calibration standards cannot be verified.

CAUTION:    Many of these chemicals are extremely toxic if inhaled or swallowed.  Wash hands
               thoroughly after handling.

       Typical stock solution preparation procedures follow for 1 L quantities, but for the purpose of
       pollution prevention, the analyst is encouraged to prepare smaller quantities when possible.
       Concentrations are calculated based upon the weight of the pure element or upon the weight of the
       compound multiplied by the fraction of the analyte in the compound.
Draft, January 2001                                                                                   11

-------
Method 200.9
                                           Equation 1

               From a pure element:
                       Where:
                              C = concentration (mg/L)
                              m = mass (mg)
                              V = volume (L)

               From pure compound:
                                                  V
                       Where:
                              C = concentration (mg/L)
                              m = mass (mg)
                              gf= gravimetric factor (mass fraction of the analyte in the compound)
       	V = volume (L)	

       7.11.1 Aluminum solution, stock, 1 mL = 1000 (jg Al:  Dissolve 1.000 g of aluminum metal,
               weighed to at least four significant figures, in 4.0 mL (1:1) HC1 and 1.0 mL concentrated
               HNO3 in a beaker.  Warm the beaker slowly to effect solution. When dissolution is
               complete, transfer solution quantitatively to a 1 L flask, add an additional 10.0 mL (1:1)
               HC1 and dilute to volume with reagent water.

       7.11.2 Antimony solution, stock, 1 mL = 1000 (jg Sb:  Dissolve 1.000 g of antimony powder,
               weighed accurately to at least four significant figures, in 20.0 mL (1:1) HNO3 and 10.0
               mL concentrated HC1. Add 100 mL reagent water and  1.50 g tartaric acid.  Warm
               solution slightly to effect complete dissolution.  Cool solution and add reagent water to
               volume  in a 1 L volumetric flask.

       7.11.3 Arsenic solution, stock, 1 mL = 1000 (jg As: Dissolve 1.320 g of As2O3 (As fraction =
               0.7574), weighed accurately to at least four significant figures, in 100 mL of reagent water
               containing 10.0 mL concentrated NH4OH.  Warm the solution gently to effect dissolution.
               Acidify  the solution with 20.0 mL concentrated HNO3 and dilute to volume in a 1 L
               volumetric flask with reagent water.

       7.11.4 Beryllium solution, stock, 1 mL = 1000 (jg Be:  DO NOT DRY. Dissolve 19.66 g
               BeSO44H2O (Be fraction = 0.0509), weighed accurately to at least four significant
               figures,  in reagent water, add 10.0 mL concentrated HNO3, and dilute to volume in a 1 L
               volumetric flask with reagent water.

       7.11.5 Cadmium solution, stock, 1 mL = 1000 (jg Cd: Dissolve 1.000 g Cd metal, acid cleaned
               with (1:9) HNO3, weighed accurately to at least four significant figures, in 50 mL (1:1)
12                                                                                 Draft, January 2001

-------
                                                                                         Method 200.9
               HNO3 with heating to effect dissolution. Let solution cool and dilute with reagent water in
               a 1 L volumetric flask.

        7.11.6 Chromium solution, stock, 1 mL = 1000 (jg Cr: Dissolve 1.923 g CrO3 (Cr fraction =
               0.5200), weighed accurately to at least four significant figures, in 120 mL (1:5) HNO3.
               When solution is complete, dilute to volume in a 1 L volumetric flask with reagent water.
        7.11.7 Cobalt solution, stock, 1 mL = 1000 (jg Co: Dissolve 1.000 g Co metal, acid cleaned with
               (1:9) HNO3, weighed accurately to at least four significant figures, in 50.0 mL (1:1)
               HNO3. Let solution cool and dilute to volume in a 1 L volumetric flask with reagent
               water.

        7.11.8 Copper solution, stock, 1 mL = 1000 (jg Cu: Dissolve 1.000 g Cu metal, acid cleaned
               with (1:9) HNO3, weighed accurately to at least four significant figures, in 50.0 mL (1:1)
               HNO3 with heating to effect dissolution. Let solution cool and dilute in a 1 L volumetric
               flask with reagent water.

        7.11.9 Iron solution, stock, 1 mL = 1000 (jg Fe:  Dissolve 1.000 g Fe metal, acid cleaned with
               (1:1) HC1, weighed accurately to four significant figures, in 100 mL (1:1) HC1 with
               heating to effect dissolution. Let solution cool  and dilute with reagent water in a 1 L
               volumetric flask.

        7.11.10       Lead solution, stock, 1 mL = 1000  (jg Pb: Dissolve  1.599 g Pb(NO3)2
                       (Pb fraction = 0.6256), weighed accurately to at least four significant figures, in a
                       minimum amount of (1:1) FINO3. Add 20.0 mL (1:1) FINO3 and dilute to volume
                       in a 1  L volumetric flask with reagent water.

        7.11.11       Manganese solution, stock, 1 mL = 1000 (jg Mn:  Dissolve  1.000 g of manganese
                       metal, weighed accurately to at least four significant figures, in 50 mL (1:1) HNO3
                       and dilute to volume in a  1 L volumetric flask with reagent water.

        7.11.12       Nickel solution, stock, 1 mL = 1000 (jg Ni: Dissolve 1.000 g of nickel metal,
                       weighed accurately to at least four significant figures, in 20.0 mL hot concentrated
                       FINO3, cool, and dilute to volume in a  1 L volumetric flask with reagent water.

        7.11.13       Selenium solution, stock, 1 mL = 1000 (jg Se: Dissolve 1.405  g SeO2 (Se fraction
                       = 0.7116), weighed accurately to at least four significant figures, in 200 mL
                       reagent water and dilute to volume in a 1 L volumetric flask with reagent water.

        7.11.14       Silver solution, stock, 1 mL = 1000 (jg Ag: Dissolve 1.000 g Ag metal, weighed
                       accurately to at least four significant figures, in 80 mL (1:1) FINO3 with heating to
                       effect dissolution. Let solution cool and dilute with reagent water in a 1 L
                       volumetric flask.  Store solution in amber bottle or wrap a clear bottle completely
                       with aluminum foil to protect solution from light.

        7.11.15       Thallium solution, stock,  1 mL = 1000 (jg Tl:  Dissolve 1.303 g T1NO3
                       (Tl fraction = 0.7672), weighed accurately to at least four significant figures, in
Draft, January 2001                                                                                   13

-------
Method 200.9
                       reagent water. Add 10.0 mL concentrated HNO3 and dilute to volume in a 1 L
                       volumetric flask with reagent water.

        7.11.16       Tin solution, stock, 1 mL = 1000 (jg Sn: Dissolve 1.000 g Sn shot, weighed
                       accurately to at least four significant figures, in an acid mixture of 10.0 mL
                       concentrated HC1 and 2.0 mL (1:1) HNO3 with heating to effect dissolution. Let
                       solution cool, add 200 mL concentrated HC1, and dilute to volume in a 1 L
                       volumetric flask with reagent water.

7.12   Preparation of calibration standards-Fresh calibration standards should be prepared every two
        weeks, or as needed. Dilute each of the stock standard solutions to levels appropriate to the
        operating range of the instrument using the appropriate acid diluent (see note). The element
        concentrations in each calibration solution should be sufficiently high to produce good
        measurement precision and to accurately define the slope of the response curve.  The instrument
        calibration should be initially verified using a quality control sample (Sections 7.15 and 9.2.4).

        NOTE:  The appropriate acid diluent for the determination of dissolved elements in water and
       for the "direct analysis " of drinking water with turbidity <1 NTU is 1 % HNO3. For total
        recoverable elements in waters,  the appropriate acid diluent is 2% HNO3 and 1 % HCl, and the
        appropriate acid diluent for total recoverable elements in sludge and solid samples is 2% HNO3
        and 2% HCl.  The reason for these different diluents is to match  the types of acids and the acid
	concentrations of the samples with the acid present in the standards and blanks.	

7.13   Blanks-Three types of blanks are required for this method. A calibration blank is used to establish
        the analytical calibration curve, a method blank is used to assess possible contamination from the
        sample preparation procedure and to assess spectral background,  and a rinse blank is used to flush
        the instrument autosampler uptake system. All diluent acids should be made from concentrated
        acids (Sections 7.2  and 7.3) and reagent water.

        7.13.1 The calibration blank consists of the appropriate acid diluent (Section 7.12 note)
               (HC1/HNO3) in ASTM Type I water. The calibration blank should be stored in a FEP
               bottle.

        7.13.2 The method blank must contain all reagents in the same volumes as used in processing the
               samples. The method blank must be carried through the same entire preparation scheme as
               the samples including sample digestion, when applicable.

        7.13.3 The rinse blank is prepared as needed by adding 1.0 mL of cone. HNO3 and 1.0 mL cone.
               HCl to 1 L of ASTM Type I water. The blank may be stored in a convenient manner.

7.14   Calibration verification (CV) solution-The CV solution is used to periodically verify instrument
        calibration during analysis. It should be prepared in the same acid mixture as the calibration
        standards (Section 7.12 note) by  combining method analytes at appropriate concentrations to
        approximate the midpoint of the calibration curve. The CV solution should be prepared from the
        same standard stock solutions used to prepare the calibration standards and stored in a FEP bottle.
        Agency programs may specify or request that additional calibration verification solutions be
        prepared at specified concentrations in order to meet specific program needs.

14                                                                                  Draft, January 2001

-------
                                                                                      Method 200.9
7.15  Quality control sample (Reference sample)-The QCS must be obtained from an outside source
       separate from standard stock solutions, and is prepared in the same acid mixture as the calibration
       standards (Section 7.12 note). For initial and periodic verification of calibration standards and
       instrument performance, analysis of a method blank that has been fortified with the QCS is
       required.  Analyte concentrations in the QCS solution should be such that the resulting solution
       will provide an absorbance reading of approximately 0.1.  The QCS solution should be stored in a
       FEP bottle and analyzed as needed to meet data quality needs. A fresh solution should be prepared
       quarterly or more frequently if instability is noted.

8.0   Sample Collection, Preservation,  and Storage

8.1    Prior to the collection of an aqueous sample, consideration should be given to the type of data
       required, (i.e., dissolved or total recoverable), so that appropriate preservation and pretreatment
       steps can be taken. The pH of all aqueous samples must be tested immediately prior to aliquots
       are removed for processing or "direct analysis" to ensure the sample has been properly preserved.
       If properly acid preserved, the sample can be held up to six months before analysis.

8.2   For the determination of dissolved metals, the sample must be filtered through a 0.45 (jm capsule
       membrane filter at the time of collection or as soon thereafter as is practical.  (A glass or metal-free
       plastic filtering apparatus is recommended to avoid possible contamination).  Use a portion of the
       filtered sample to rinse the filter flask, discard this portion and collect the required volume of
       filtrate. Acidify the filtrate to pH <2 with (1:1) HNO3 immediately following filtration.

8.3   For the determination of total recoverable elements in aqueous samples, samples are not filtered,
       but acidified with (1:1) HNO3 to pH <2 (normally, 3 mL of (1:1) acid per liter of sample is
       sufficient for most ambient and drinking water samples). Preservation may be done at the time of
       collection. However, to avoid the hazards of strong acids in the field, transport restrictions, and
       possible contamination, it is recommended that the samples be returned to the laboratory within
       two weeks of collection and acid preserved upon receipt in the laboratory. Following acidification,
       the sample should be mixed, held for  16 hours, and then verified to be pH <2 immediately prior to
       withdrawing an aliquot for processing or "direct analysis."  If for some reason such as high
       alkalinity, sample pH is >2, more acid must be added and the sample held for an additional 16
       hours until verified to be pH <2.

       NOTE:  When the nature of the sample is either unknown or known to be hazardous,
	acidification should be done in a fume hood (Section 5.2).	

8.4   Solid samples usually require no preservation prior to analysis other than storage at 4C.  There is
       no established holding time limitation for solid samples.

8.5   For aqueous samples, a field blank should be prepared and analyzed if required by the data user.
       Use the same container and acid as used in sample collection.

9.0   Quality Control

9.1    Each laboratory applying this method is required to maintain a formal quality assurance program.
       The minimum requirements of this program consist of an initial demonstration of laboratory

Draft, January 2001                                                                                  15

-------
Method 200.9
        capability, analysis of samples spiked with metals of interest to evaluate and document data
        quality, and analysis of standards and blanks as tests of continued performance.  Laboratory
        performance is compared to established performance criteria to demonstrate that results of the
        analysis meet the performance criteria of the method.

        9.1.1  The analyst must make an initial demonstration of the ability to generate acceptable
               accuracy and precision with this method.  This ability is established as described in
               Section 9.2.

        9.1.2  In recognition of advances that are occurring in analytical technology, the analyst is
               permitted to exercise certain options to eliminate interferences or lower the costs of
               measurements. These options include alternate digestion, preconcentration, cleanup
               procedures, and changes in instrumentation. Alternate determinative techniques, such as
               the substitution of a colorimetric technique or changes that degrade method performance,
               are not allowed.  If an analytical technique other than the techniques specified in this
               method is used, then that technique must have a specificity equal to or better than the
               specificity of the techniques in the method for the analytes of interest.

               9.1.2.1       Each time the method is modified, the analyst is required to repeat the
                              procedure in Section 9.2.  If the change will affect the detection limit of
                              the method, the laboratory is required to demonstrate that the MDLs (40
                              CFR Part 136, Appendix B) are lower than the MDLs for the analytes in
                              this method, or one-third the regulatory compliance level, whichever is
                              higher. If the change will affect calibration, the analyst must recalibrate
                              the instrument according to Section 10.0.

               9.1.2.2       The laboratory is required to maintain records of modifications made to
                              this method. These records include the  following, at a minimum:

                       9.1.2.2.1      The names, titles, addresses, and telephone numbers of the
                                      analyst(s) who performed the analyses and modification, and of
                                      the quality control officer who witnessed and will  verify the
                                      analyses and modification.

                       9.1.2.2.2     A listing of metals measured, by name and CAS Registry number.

                       9.1.2.2.3     A narrative stating reason(s)  for the modification(s).

                       9.1.2.2.4     Results from all quality control (QC) tests comparing the
                                      modified method to this method, including:

                                      (a)     Calibration
                                      (b)    Calibration verification
                                      (c)     Initial precision and recovery
                                      (d)     Analysis of blanks
                                      (e)     Accuracy assessment
16                                                                                   Draft, January 2001

-------
                                                                                        Method 200.9
                       9.1.2.2.5      Data that will allow an independent reviewer to validate each
                                      determination by tracing the instrument output (peak height, area,
                                      or other signal) to the final result.  These data are to include,
                                      where possible:

                                      (a)      Sample numbers and other identifiers
                                      (b)      Digestion/preparation or extraction dates
                                      (c)      Analysis dates and times
                                      (d)      Analysis sequence/run chronology
                                      (e)      Sample weight or volume
                                      (f)      Volume before the extraction/concentration step
                                      (g)      Volume after each extraction/concentration step
                                      (h)      Final volume before analysis
                                      (i)      Injection volume
                                      (j)      Dilution data, differentiating between dilution of a sample
                                              or extract
                                      (k)      Instrument and operating conditions (make, model,
                                              revision, modifications)
                                      (1)      Sample introduction system (ultrasonic nebulizer, flow
                                              injection system, etc.)
                                      (m)     Preconcentration system
                                      (n)      Operating conditions (background corrections,
                                              temperature program, flow rates, etc.)
                                      (o)      Detector (type, operating conditions, etc.)
                                      (p)      Spectra, printer tapes, and other recordings of raw data
                                      (q)      Quantitation reports, data  system outputs, and other data
                                              to link raw data to results reported

        9.1.3  Analyses of blanks are required to demonstrate freedom from contamination. Section 9.5
               describes the required types, procedures, and criteria for analysis of blanks.

        9.1.4  Analyses of MS and MSD samples are required to demonstrate the accuracy and precision
               of the method and to monitor for matrix interferences (Section  9.4). When results of these
               spikes indicate atypical method performance, alternative extraction or cleanup techniques
               must be used to bring method performance within acceptable limits.  If method
               performance cannot be brought within the limits given in  this method, the  results may not
               be reported for regulatory compliance purposes.

        9.1.5  The laboratory must, on an ongoing basis, demonstrate through calibration verification
               (Section 9.3) and through analysis of the ongoing precision  and recovery standard (Section
               9.6) that the analytical system is meeting the performance criteria.

        9.1.6  The laboratory must maintain records to  define the quality of data that are generated.
               Development of accuracy statements is described in Section 9.4.4.1 and 9.6.7.

        9.1.7  All samples must be associated with an acceptable OPR, MS/MSD, IPR,  and
               uncontaminated blanks.
Draft, January 2001                                                                                   17

-------
Method 200.9
9.2    Initial demonstration of laboratory capability.

       9.2.1  Method detection limitTo establish the ability to detect the trace metals of interest, the
               analyst must determine the MDL for each analyte according to the procedure in 40 CFR
               136, Appendix B using the apparatus, reagents, and standards that will be used in the
               practice of this method.  The laboratory must produce an MDL that is less than or equal to
               the MDL listed in Table  1 (to be confirmed during validation study), or one-third the
               regulatory compliance limit, whichever is greater. MDLs should be determined when a
               new operator begins work or whenever a change  in instrument hardware or operating
               conditions is made that may affect the MDL.  MDLs must be determined for solids with
               clean sand or soil if solid samples are to be analyzed, peat moss for biosolids and/or for
               reagent water if aqueous samples are to be analyzed. MDLs also must be determined for
               biosolids with peat moss if sludge samples are to be analyzed for arsenic, cadmium,
               copper, lead, nickel, and selenium.

       9.2.2  Initial precision and recovery (IPR)-To establish the ability to generate acceptable
               precision and recovery, the analyst must perform the following operations.

               9.2.2.1        Spike four aliquots of reagent water for aqueous samples, clean sand or
                              soil for solid samples, or peat moss for biosolid samples, with the metal(s)
                              of interest at one to five times the ML. Analyze the four aliquots
                              according to the procedures in Section 11.0.  All digestion, extraction, and
                              concentration steps, and the containers, labware, and reagents that will be
                              used with samples must be used in this test.

               9.2.2.2       Using results of the set of four analyses, compute the average percent
                              recovery (X) for the metal(s) in each aliquot and the standard deviation of
                              the recovery (s) for each metal.

               9.2.2.3       For each metal, compare s and X with the corresponding limits for IPR in
                              (Table 2- to  be determined in validation study). If s and X for all metal(s)
                              meet the acceptance criteria, system performance is acceptable and
                              analysis of blanks and samples may begin. If, however, any individual s
                              exceeds the precision limit or any individual X falls outside the range for
                              accuracy, system performance is unacceptable for that metal.  Correct the
                              problem and repeat the test.

       9.2.3  Linear dynamic range (LDR)-The upper limit of the LDR must be established for the
               wavelength used for each analyte by determining the signal responses from a minimum of
               six different concentration standards across the range, two of which should be close to the
               upper limit of the LDR.  Determined LDRs must be documented and kept on file.  The
               linear calibration range which may be used for the analysis of samples should be judged by
               the analyst from the resulting data. The upper LDR limit should be an observed signal no
               more than 10% below the level extrapolated from the four lower standards. Sample
               analyte concentrations that exceed the upper limit of the linear calibration range must
               either be diluted and analyzed again with concern for memory effects (Section 4.5) or be
18                                                                                  Draft, January 2001

-------
                                                                                       Method 200.9
               analyzed by another approved method. The LDRs should be verified annually or
               whenever, in the judgement of the analyst, there is a change in analytical performance.

        NOTE: Multiple clean out furnace cycles may be necessary in order to fully define or utilize
        the LDRfor certain elements such as chromium. For this reason the upper limit of the linear
	calibration range may not correspond to the upper LDR limit.	

        9.2.4  Quality Control Sample (QCS)-When beginning the use of this method, quarterly, and as
               required to meet data quality needs, the analyst must verify the calibration standards and
               acceptable instrument performance by preparing and analyzing three aliquots of a
               reference sample (Section 7.15).  To verify the calibration standards, the determined mean
               concentration from three analyses of the reference sample must be within  5% of the
               stated reference sample values. If the reference  sample results are not within the required
               limits, an immediate second analysis of the reference sample is recommended to confirm
               unacceptable performance.  If the calibration standards and acceptable instrument
               performance cannot be verified, the source of the problem must be identified and corrected
               before either proceeding  with further sample analyses.

9.3     Calibration verification (CV) solution-A laboratory must analyze a CV solution (Section 7.12) and
        a calibration blank immediately following each calibration, after every 10th sample (or more
        frequently, if required) and at the end of the sample run.

        9.3.1  The calibration blank results must always be less than the analyte ML, or one-third the
               regulatory compliance level, whichever is greater. The results must also by greater than a
               negative signal in  concentration units equal to the ML.

        9.3.2  Analysis of the CV solution immediately following calibration must verify that the
               instrument is within performance criteria to be determined by the validation study (Table 2
               - to be determined by the validation study).

        9.3.3  If calibration cannot be verified within the specified limits, reanalyze either or both the CV
               solution and the calibration blank. If the second analysis of the CV solution or the
               calibration blank confirms that the calibration is outside acceptable limits, sample analysis
               must be discontinued, the cause determined, and/or, in the case of drift, the instrument
               recalibrated. All samples following the last acceptable CV solution and calibration blank
               must be analyzed  again.  Analysis data of the  calibration blank and CV solution must be
               kept on file with sample  analyses data.

9.4     Matrix spike (MS) and matrix spike duplicates (MSD)-To assess the performance of the method
        on a given  sample matrix,  the laboratory must spike, in duplicate, a minimum of 10% (one sample
        in ten) of the samples from a given sampling site or, if for compliance monitoring, from a given
        discharge.  Blanks may not be used for MS/MSD analysis.

        9.4.1  The concentration of the  MS and MSB spike shall be determined as follows:

               9.4.1.1        If, as in  compliance monitoring, the concentration of analytes in the
                              sample is being checked against a regulatory concentration limit, the

Draft, January 2001                                                                                  19

-------
Method 200.9
                              spiking level shall be at that limit or at 1-5 times the background
                              concentration of the sample, whichever is greater.

               9.4.1.2       If the concentration of analytes in a sample is not being checked against a
                              regulatory concentration limit, the spike shall be at 1-5 times the
                              background concentration of the sample.

               9.4.1.3       For solid and sludge samples, the concentration added should be expressed
                              as mg/kg and is calculated for a one gram aliquot by multiplying the
                              added analyte concentration (mg/L) in solution by the conversion factor
                              100 (mg/L x O.lL/O.OOlkg = 100, Section 12.4). (For notes on Ag, see
                              Sections  1.6).

        9.4.2  Assessing spike recovery.

               9.4.2.1        To determine the background concentration (B), analyze one sample
                              aliquot from each set of 10 samples from each site or discharge according
                              to the procedure in Section 11. If the expected background concentration
                              is known from previous experience or other knowledge, the spiking level
                              may be established a priori.

               9.4.2.2       Prepare a standard  solution to produce an appropriate concentration in the
                              sample (Section 9.4.1).
       NOTE:  The concentration of iron and aluminum in solids can vary greatly and is not
       necessarily predictable.  Fortifying these analytes in routine samples at the same concentration
       used for the OPR may prove to be of little use in assessing data quality for these analytes.  For
       these analytes sample dilution and reanalysis is recommended.  After subtraction of the OPR
       spike, the calculated sample concentration after dilution should agree within 10% of the original
       determination of sample concentration. Also, if specified by the data user, laboratory or
       program, samples can be fortified at higher concentrations, but even major constituents should
       be limited to <25 mg/L so as not to alter the sample matrix and possibly affect the analysis.	

               9.4.2.2       Spike two additional sample aliquots with the spiking solution and analyze
                              these aliquots to determine the concentration after spiking (A).  Calculate
                              the percent recovery (P) in each aliquot (Equation 2).
20                                                                                  Draft, January 2001

-------
                                                                                       Method 200.9
                                           Equation 2
                                                  (A- B}
                                      p= 100*-	-
                                                      T
                              where:
                                     P = Percent recovery
                                     A = Measured concentration ofanalyte after spiking
                                     B = Measured concentration ofanalyte before spiking
                             	T = True concentration of the spike	
        9.4.3  Compare the percent recovery with the QC acceptance criteria in Table 2 (to be
               determined in validation study).

               9.4.3.1        If P falls outside the designated range for recovery in Table 2, the results
                              have failed to meet the established performance criteria.  If P is
                              unacceptable, analyze the OPR standard (Section 9.6). If the OPR is
                              within established performance criteria (Table 2), the analytical system is
                              within specification and the problem can be attributed to  interference by
                              the sample matrix. The data user should be informed that the result for
                              that analyte in the unfortified sample is suspect due to either the
                              heterogeneous nature of the sample or matrix effects.

               9.4.3.2        If the analyte MS/MSD recovery is <70% and the background absorbance
                              is <1.0, the analyte addition test (Section 9.7) should be performed on an
                              undiluted portion of an unfortified sample aliquot. Test results should be
                              evaluated as follows:

                      9.4.3.2.1     If recovery of the analyte addition test (<85%) confirms a low
                                     recovery for the MS/MSD, a suppressive matrix interference is
                                     indicated and an unfortified sample aliquot must be analyzed by
                                     the method of standard additions (Section 11.6).

                      9.4.3.2.2     If recovery of the analyte addition test is between 85 - 115%, a
                                     low  recovery of the analyte in the MS/MSD (<70%) may be
                                     related to the heterogeneous nature of the sample, the result of
                                     precipitation loss  during sample preparation, or an incorrect
                                     addition prior to preparation.  Report analyte data determined
                                     from the analysis  of an unfortified sample aliquot.

               9.4.3.3        If laboratory performance is shown to be acceptable (Section 9.5.1 and
                              Section 9.6), but analyte recovery in the MS/MSD is either >130% or
                              above the upper calibration limit, and the background absorbance is <1.0,
                              the analyte addition test should be performed (Section 9.7) on an
                              unfortified sample aliquot. (If the MS/MSD concentration is above the
                              upper calibration limit, dilute a portion of an unfortified aliquot with
Draft, January 2001                                                                                   21

-------
Method 200.9
                              acidified reagent water before completing the analyte addition test).
                              Evaluate the test results as follows:

                       9.4.3.3.1      If the percent recovery of an analyte addition test is >115%, an
                                      enhancing matrix interference (albeit rare) is indicated and the
                                      unfortified sample aliquot or its appropriate dilution must be
                                      analyzed by the method of standard additions (Section 11.6).

                       9.4.3.3.2      If the percent recovery of an analyte addition test is between 85 -
                                      115%, high recovery in the MS/MSD may have been caused by
                                      random sample contamination, sample heterogeneity, or incorrect
                                      addition of the analyte prior to sample processing.  Report
                                      analytical  data from an unfortified sample aliquot or its
                                      appropriate dilution.

                       9.4.3.3.3      If the percent recovery of an analyte addition test is <85%, a
                                      heterogenous sample with a suppressive matrix may be indicated.
                                      Other possible causes may be  a combination of random
                                      contamination and a positive matrix interference. Reported data
                                      should be  flagged accordingly.

               9.4.3.4       If laboratory performance is shown to  be acceptable (Section 9.5.1 and
                              Section 9.6),  but the background absorbance is >1.0, a nonspecific
                              spectral interference should be suspected. A portion of the unfortified
                              aliquot should be diluted (1:3) with acidified reagent water and analyzed
                              again. (Dilution may dramatically reduce molecular background to an
                              acceptable level. Ideally, background  absorbance in the unfortified
                              aliquot diluted (1:3) should be < 1.0. However, additional dilution may be
                              necessary). If dilution reduces background absorbance to an acceptable
                              level (<1.0), complete the analyte addition test (Section 9.7) on a dilute
                              unfortified aliquot. Evaluate test results as follows:

                       9.4.3.4.1      If recovery of the analyte addition test is between 85 - 115%,
                                      report the  analytical data acquired from the dilute,  unfortified
                                      aliquot.

                       9.4.3.4.2      If recovery of the analyte addition test is outside the range  of 85 -
                                      115%, complete sample analysis by analyzing a dilute, unfortified
                                      aliquot following the method of standard additions (Section 11.6).
               9.4.3.5       If either analysis of MS/MSD samples or application of the analyte
                              addition test indicate a positive interference, all other samples in the batch
                              which are typical and have a matrix similar to the MS/MSD or the tested
                              samples must be analyzed in the same manner. Also, the data user must
                              be informed when a matrix interference is so severe that it prevents the
22                                                                                   Draft, January 2001

-------
                                                                                      Method 200.9
                              successful analysis of the analyte or when the heterogeneous nature of the
                              sample precludes the use of duplicate analyses.

               9.4.3.6        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 an analyst's and a laboratory's ability to
                              perform a method acceptably.

       9.4.4  Recovery for samples should be assessed and records maintained.

               9.4.4.1        After the  analysis of five samples of a given matrix type (river water,
                              biosolids, etc.) for which the metal(s) pass the tests in Section 9.4.3,
                              compute the average percent recovery (P) and the standard deviation of
                              the percent recovery (SP) for the metal(s).  Express the accuracy
                              assessment as a percent recovery interval from P - 2SP to P + 2SP for
                              each matrix. For example, if P = 90% and  SP = 10% for five analyses,
                              the accuracy interval is expressed as 70 - 110%.

               9.4.4.2        Update the accuracy assessment for each metal in each matrix on a
                              regular basis (e.g., after each 5-10 new measurements).

       9.4.5  Precision of matrix spike and matrix spike duplicate.

               9.4.5.1        Calculate the relative percent difference (RPB) between the MS and MSB
                              (Equation 3).  Use the concentrations found in the MS and MSB. Bo not
                              use the recoveries calculated in Section 9.4.3 for this calculation because
                              the RPB is inflated when the background concentration is near the  spike
                              concentration.

                                           Equation 3
                                                  (A + A)
                      where:
                             RPD = Relative percent difference
                             D, = Concentration of the analyte in the MS sample.
                     	D2 = Concentration of the analyte in the MSP sample.
               9.4.5.2        The relative percent difference between the matrix spike and the matrix
                              spike duplicate must be less than 20% (RPB acceptance value will be
                              verified in the validation study).  If this criterion is not met, the analytical
                              system is out of control. In this case, correct the problem and reanalyze
                              all samples in the sample batch associated with the MS/MSB that failed
                              the RPB test.
Draft, January 2001                                                                                  23

-------
Method 200.9
9.5    Blanks.
        9.5.1  Method blank.
               9.5.1.1
               9.5.1.2
Prepare a method blank with each sample batch (samples of the same
matrix -reagent water for aqueous samples, clean sand or soil for solid
samples, peat moss for biosolid samples) started through the sample
preparation process (Section 11.0) on the same  12-hour shift, for a
maximum of 20 samples. Analyze the blank immediately after the OPR is
analyzed (Section 9.6) to demonstrate freedom from contamination.

If the analyte(s) of interest or any potentially interfering substance is
found in the method blank at a concentration equal to or greater than the
ML (Table 1 to be determined during the validation study) or 1/3 the
regulatory compliance level, whichever is greater, sample  analysis must be
halted, the source of contamination determined,  the samples and a new
method blank prepared, and the new sample batch and method blank
analyzed.
               9.5.1.3
               9.5.1.4
        9.5.2  Field blank.
Alternatively, if a sufficient number (three minimum) of blanks are
analyzed, the average concentration plus two standard deviations must be
less than the regulatory compliance level.

If the result for a single method blank remains above the ML or if the
result for the average concentration plus two standard deviations of three
or more blanks exceeds the regulatory compliance level, results for
samples associated with those blanks may not be reported for regulatory
compliance purposes.  Stated another way, results for IPR tests (Section
9.2) and all samples must be associated with an uncontaminated method
blank before these results may be reported for regulatory compliance
purposes.
               9.5.2.1        Analyze the field blank(s) shipped with each set of samples (samples
                              collected from the same site at the same time, to a maximum of 10
                              samples). Analyze the blank immediately before analyzing the samples in
                              the batch.

               9.5.2.2        If the metal of interest or any potentially interfering substance is found in
                              the field blank at a concentration equal to or greater than the ML, or
                              greater than one-fifth the level in the associated sample(s), whichever is
                              greater, results for the associated samples may be the result of
                              contamination and may not be reported for regulatory compliance
                              purposes.
24
                                                      Draft, January 2001

-------
                                                                                        Method 200.9
               9.5.2.3       Alternatively, if a sufficient number (three minimum) of field blanks are
                              analyzed to characterize the nature of the field blank, the average
                              concentration plus two standard deviations must be less than the
                              regulatory compliance level or less than one-half the level in the associated
                              sample for that analyte, whichever is greater.

               9.5.2.4       If contamination of the field blanks and associated samples is known or
                              suspected, the laboratory should communicate this to the sampling team
                              so that the source of contamination can be identified and corrective
                              measures taken prior to sampling.

        9.5.3  Equipment blanksBefore any sampling equipment is used at a given site, it is
               recommended that the laboratory or cleaning facility generate equipment blanks to
               demonstrate that the sampling equipment is free from contamination.  Two types of
               equipment blanks are recommended: bottle blanks and sampler check blanks.

               9.5.3.1        Bottle blanksAfter undergoing  appropriate cleaning procedures (Section
                              6.9), bottles should be subjected to conditions of use to verify the
                              effectiveness of the cleaning procedures. A representative set of sample
                              bottles should be filled with reagent water acidified to pH < 2 and allowed
                              to stand for a minimum of 24 hours.  Ideally, the time that the bottles are
                              allowed to stand should be as close as possible to  the actual time that
                              sample will be in contact with the bottle. After standing, the water should
                              be analyzed for any signs of contamination.  If any bottle shows signs of
                              contamination, the problem must  be identified, the cleaning procedures
                              corrected or cleaning solutions changed, and all affected bottles cleaned
                              again.

               9.5.3.2       Sampler check blanksSampler  check blanks are generated in the
                              laboratory or at the equipment cleaning contractor's facility by processing
                              reagent water through  the sampling devices using  the same procedures
                              that are used in the field.

                       9.5.3.2.1      Sampler check blanks are generated by filling a large carboy or
                                      other container with reagent water (Section 7.1) and processing
                                      the reagent water through the equipment using the same
                                      procedures that are used  in the field. For example, manual grab
                                      sampler check blanks are collected by directly submerging a
                                      sample bottle  into the water, filling the bottle, and capping.
                                      Subsurface sampler check blanks are collected by immersing the
                                      sampler into the water and pumping water into  a sample
                                      container.  Whatever precautions and equipment are used in the
                                      field should also be used  to generate these blanks.

                       9.5.3.2.2      The sampler check blank should be analyzed using the procedures
                                      in this method. If the target analyte(s) or  any potentially
                                      interfering substance is detected in the blank, the  source of

Draft, January 2001                                                                                   25

-------
Method 200.9
                                     contamination or interference must be identified and the problem
                                     corrected. The equipment should be demonstrated to be free from
                                     contamination before the equipment is used in the field.

                      9.5.3.2.3     Sampler check blanks should be run on all equipment that will be
                                     used in the field. If, for example, samples are to be collected
                                     using both a grab sampling device and a subsurface sampling
                                     device, a sampler check blank must be run on both pieces of
                                     equipment.

9.6    Ongoing precision and recovery.

       9.6.1  For aqueous samples, prepare an OPR solution identical to the IPR aliquots (Section
               9.2.2).  The solution must be analyzed with each preparation batch (samples of the same
               matrix started through the sample preparation process (Section 11.0) on the same 12-hour
               shift, to a maximum of 20 samples).

       9.6.2  For solid samples, the use of clean sand or soil fortified as in Section 9.6.1 is
               recommended.

       9.6.3  For biosolid samples, the use of peat moss fortified as in Section 9.6.1 is recommended.

       9.6.4  Analyze the OPR solution before the method blank and samples are analyzed.

       9.6.5  Compute the percent recovery of each metal in the OPR sample.

       9.6.6  For each metal, compare the OPR concentration to the limits for ongoing recovery in
               (Table 2- to be determined in validation study). If all metal(s) meet the acceptance criteria,
               system performance is acceptable and analysis of blanks and samples may proceed. If,
               however, any individual recovery falls outside of the range given, the analytical processes
               are not being performed properly for that metal.  Correct the problem, prepare the sample
               batch again, and repeat the OPR test.

       9.6.7  Add results that pass the specifications in Section 9.6.6 to IPR and previous OPR data for
               each metal in each matrix.  Update QC charts to form a graphic representation of
               continued laboratory performance. Develop a statement of laboratory accuracy for each
               metal in each matrix type by calculating average percent recovery (P) and standard
               deviation of percent recovery (SP). Express accuracy as a recovery interval from P - 2SP
               to P + 2SP.  For example, if P = 95% and SP = 5%, accuracy is 85 - 105%.

9.7    An analyte addition test can be used to assess possible matrix interference effects and the need to
       complete a sample analysis using the method  of standard additions (MSA, Section 11.6).  Results
       of this test should not be considered conclusive unless the determined sample background
       absorbance is <1.0.  An analyte standard, when added to a portion of a prepared sample or its
       dilution, should be recovered to within 85-115% of the known value.  The analyte addition may
       be added directly to sample in the furnace and should produce a minimum level absorbance of 0.1.
       The concentration of the analyte addition plus that in the sample should not exceed the linear

26                                                                                 Draft, January 2001

-------
                                                                                        Method 200.9
        calibration range of the analyte.  If the analyte is not recovered within the specified limits, a matrix
        effect should be suspected and the sample must be analyzed by MSA (Section 11.6).
10.0   Calibration  and  Standardization

10.1   Prior to an initial calibration, the linear dynamic range of the analyte must be determined (Section
        9.2.3) using optimized instrument operating conditions (Section 11.5).  For all determinations,
        allow an instrument and hollow cathode lamp warm up period of not less than 15 minutes.  If an
        EDL is to be used, allow 30 minutes for warm up.

10.2   For initial and daily operation, calibrate the instrument according to the instrument manufacturer's
        recommended procedures using the calibration blank (Section 7.13.1) and calibration standards
        (Section 7.12) prepared at three or more concentrations within the usable linear dynamic range of
        the analyte (Section 9.2.3). The lowest calibration point (excluding the calibration blank) must be
        equal to the ML (Table  1, to be determined during the validation study).

10.2   The calibration line should include at least three non-zero points with the high standard near the
        upper limit of the linear dynamic range (Section 9.2.3) and the low standard  that contains the
        analyte(s) of interest at the ML (to be determined during the validation study).  Replicates of a
        calibration blank (Section 7.13.1) and the highest standard provide an optimal distribution of
        calibration standards to  minimize the confidence band for a straight-line calibration in a response
        region with uniform variance (Reference 12).

10.3   Calculate the slope and  intercept of a line using weighted linear regression. Use the inverse of the
        standard's concentration squared (1/x2) as the weighting factor.  The calibration is acceptable if the
        R2 is greater than 0.995 and the absolute value of the intercept is less than the MDL for the target
        analyte.  If these  conditions are not met, then the laboratory may not report data analyzed under
        that calibration and must recalibrate the instrument.

10.4   The concentration of samples is determined using Equation 4.

                                            Equation 4

                                           y = mx + b

                      where  y = sample concentration
                              m = slope (calculated in Section 10.3)
                              x = instrument response
	b = intercept (calculated in Section 10.3)	

10.5   Response factor may be calculated as an alternative to weighted linear regression for instrument
        calibration. Calculate the response factor (RF) of the analytes for each of the standards (Equation
        5.)
Draft, January 2001                                                                                   27

-------
Method 200.9
                                           Equation 5
                                                    x
                      where:
                             Rx = Peak height or area
                     _ Cx = Concentration of standard x
        10.5.1 Calculate the mean response factor (RFm), the standard deviation of the RFm, and the
               relative standard deviation (RSD) of the mean (Equation 6).

                                           Equation 6
                                                     SD
                                      RSD= 100*-
                      where:
                             RSD = Relative standard deviation of the mean
                             SD = Standard deviation of the RFm
                     	RFm = the mean response factor	
        10.5.2 Performance criteria for the calibration will be calculated after the validation of the
               method.

11.0   Procedure

11.1    Aqueous sample preparation (Dissolved analytes)-For the determination of dissolved analytes in
        ground and surface waters, pipet an aliquot (>20 mL) of filtered, acid preserved sample into a 50
        mL polypropylene centrifuge tube. Add an appropriate volume of (1:1) HNO3 to adjust the acid
        concentration of the aliquot to approximate a 1% (v/v) HNO3 solution (e.g., add 0.2 mL (1:1)
        HNO3 to a 20 mL aliquot of sample).  Cap the tube and mix.  The  sample is now ready for
        analysis. Allowance for sample dilution should be made in the calculations (Section 12).

        NOTE: If a precipitate  is formed during acidification, transport, or storage, the sample aliquot
        must be treated using the procedure described in Sections 11.2.2 through 11.2.7 prior to
	analysis.	

11.2    Aqueous sample preparation-Total recoverable analytes.

        11.2.1 For "direct analysis" of total recoverable analytes in drinking water samples containing
               turbidity <1 NTU, treat an unfiltered acid preserved sample aliquot using the sample
               preparation procedure described in Section 11.1.1. Make allowance for sample dilution in
               the data calculation (Sections  12). For determination of total recoverable analytes in all
               other aqueous samples, follow the procedure given in Sections 11.2.2 through  11.2.7.

        11.2.2 For determination of total recoverable analytes in aqueous samples (other than drinking
               water with <1 NTU turbidity), transfer a 100 mL (  1 mL) aliquot from a well mixed,

28                                                                                Draft, January 2001

-------
                                                                                      Method 200.9
               acid-preserved sample to a 250 mL Griffin beaker.  (When necessary, smaller sample
               aliquot volumes may be used).

       NOTE: If the sample is not a biosolids sample and contains undissolved solids >1%, a well
       mixed, acid preserved aliquot containing no more than 1 g paniculate material should be
       cautiously evaporated to near 10 mL and extracted using the acid-mixture procedure described
	in Sections 11.3.3 through 11.3.6.	

       11.2.3 Add 2 mL (1:1) HNO3 and 1.0 mL of (1:1) HC1 to a beaker containing the measured
               volume of sample. Place the beaker on the hot plate for solution evaporation.  The hot
               plate should be located in a fume hood and previously adjusted to provide evaporation at a
               temperature of approximately but no higher than 85 C. (See the following note).  The
               beaker should be covered with an elevated watch glass to prevent sample contamination
               from the fume hood environment. Other contamination avoidance steps should be taken as
               needed.

       NOTE: For proper heating, adjust the temperature control of the hot plate such that an
       uncovered Griffin beaker containing 50 mL of water placed in the center of the hot plate can be
       maintained at a temperature approximately but no higher than 85C.  (Once the beaker is
	covered with a watch glass the temperature of the water will rise to approximately 95C).	

       11.2.4 Reduce the volume of the sample aliquot to about 20 mL by gentle heating at 85 C. DO
               NOT BOIL.  This step takes about two hours for a  100 mL aliquot with the rate of
               evaporation rapidly increasing as the sample volume approaches 20 mL. (A spare beaker
               containing 20 mL of water can be used as a gauge).

       11.2.5 Cover the lip of the beaker with a watch glass to reduce additional evaporation and gently
               reflux the sample for 30 minutes. (Slight boiling may occur, but vigorous boiling must be
               avoided to prevent loss of the HC1-H2O azeotrope).

       11.2.6 Allow the beaker to cool. Quantitatively transfer the sample solution to a 50 mL
               volumetric flask.  Add reagent water to bring the final volume of the sample solution to 50
               mL.  Stopper the volumetric  flask and mix.

       11.2.7 Allow any undissolved material to settle overnight,  or centrifuge a portion of the prepared
               sample until clear. (If after centrifuging or standing overnight a sample contains
               suspended solids that would clog or adversely affect an instrument sample introduction
               system, a portion of the  sample may be filtered prior to analysis. However, care should be
               exercised to avoid potential contamination from filtration). The sample is now ready for
               analysis. Because the effects of various matrices on the stability of diluted samples cannot
               be characterized, all analyses should be performed as soon as possible after sample
               preparation.

11.3  Solid sample preparation-Total recoverable analytes.

       11.3.1 For the determination of total recoverable analytes in solid samples, mix the sample
               thoroughly and transfer a portion (>20 g) to a tared  weighing dish. For samples with

Draft, January 2001                                                                                 29

-------
Method 200.9
               <35% moisture, a 20 g portion is sufficient. For samples with moisture >35%, a larger
               aliquot of 50 - 100 g is required. Dry the sample to a constant weight at 60C (The
               sample is dried at 60 C to prevent the loss of volatile metallic compounds).

        11.3.2 To achieve homogeneity, sieve the dried sample using a 5-mesh polypropylene sieve, and
               grind it with a mortar and pestle. (The sieve, mortar, and pestle should be cleaned between
               samples). From the dried, ground material, weigh a representative 1.0  0.01 g aliquot
               (W) of the sample and transfer it to a 250 mL Phillips beaker for acid extraction.

        11.3.3 To the beaker, add 4 mL of (1:1) HNO3 and 10 mL of (1:4) HC1. Cover the beaker with a
               watch glass. Place the beaker on a hot plate for reflux extraction of analytes. The hot
               plate should be located in a fume hood and previously adjusted to provide a reflux
               temperature of approximately 95 C.

        NOTE: For proper  heating, adjust the temperature control of the hot plate such that an
        uncovered Griffin beaker containing 50 mL of water placed in the center of the hot plate can be
        maintained at a temperature approximately but no higher than 85C.  (Once the beaker is
        covered with a watch  glass the temperature of the water will rise to approximately 95 C).	

        11.3.4 Heat the sample and gently reflux for 30 minutes. Very slight boiling may occur, but
               vigorous boiling must be avoided to prevent loss of the HC1-H2O  azeotrope.  Some
               solution evanoration will occur (anDroximatelv 3-4  mL).
vigorous ooiiing musi oe avoiueu 10 preveni loss 01 me nv
solution evaporation will occur (approximately 3-4 mL).
        11.3.5 Allow the sample to cool and quantitatively transfer the extract to a 100 mL volumetric
               flask.  Dilute to volume with reagent water, stopper, and mix.

        11.3.6 Allow the sample extract solution to stand overnight to separate insoluble material or
               centrifuge a portion of the sample solution until clear.  (If, after centrifuging or standing
               overnight, the extract solution contains suspended solids that would clog or affect the
               sample introduction system, a portion of the extract solution may be filtered prior to
               analysis.  However, care should be exercised to avoid contamination from filtration). The
               sample extract is now ready for analysis.  Because the effects of various matrices on the
               stability of diluted samples cannot be characterized, all analyses should be performed as
               soon as possible after completed sample preparation.

        11.3.7 Determine the total solids content of the sample using the procedure in Appendix A.

11.4   Sludge sample preparation-Total recoverable analytes.

        11.4.1 Determination of total recoverable analytes in  sludge samples containing estimated total
               suspended solids > 1% (w/v).

               11.4.1.1      Mix the sample thoroughly. Transfer a portion (>20  g) of the sample to a
                              tared weighing dish, weigh the sample, and record the wet weight.   For
                              samples with <35% moisture, a 20 g portion is sufficient. For samples
                              with moisture >35%, a larger aliquot of 50 - 100 g is required. Dry the
30                                                                                 Draft, January 2001

-------
                                                                                     Method 200.9
                             sample to a constant weight at 60 C (The sample is dried at 60 C to
                             prevent the loss of volatile metallic compounds).

               11.4.1.2      To achieve homogeneity, sieve the dried sample using a 5-mesh
                             polypropylene sieve and grind it in a mortar and pestle.  (The sieve,
                             mortar, and pestle should be cleaned between samples). From the dried,
                             ground material weigh a representative 1.0  0.01 g aliquot (W) of the
                             sample and transfer to a 250 mL Phillips beaker for acid extraction.

               11.4.1.3      Add 1 OmL of (1:1) HNO3 to the beaker and cover the beaker with a
                             watch glass. Place the beaker on a hot plate and reflux the sample for 10
                             minutes.  Remove the sample from the hot plate and allow to cool. Add 5
                             mL of concentrated HNO3 to the beaker, replace the watch glass, return to
                             the hot plate, and reflux for 30 minutes.  Repeat this last step once.
                             Remove the beaker from the hot plate and allow to cool.  Add 2 mL  of
                             reagent water and 3 mL of 30% H2O2. Place the beaker on the hot plate
                             and heat the sample until a gentle effervescence is observed.   Once the
                             reaction has subsided, additional 1 mL aliquots of 30% H2O2 should be
                             added until no effervescence is observed.  The total amount of 30% H2O2
                             added should not exceed 10 mL. Add 2 mL concentrated HC1 and 10 mL
                             of reagent water to the sample, cover with a watch glass, and reflux for 15
                             minutes.

               11.4.1.4      Cool the  sample and dilute to 100 mL with reagent water. Any remaining
                             solid material should be allowed to settle, or an aliquot of the final sample
                             may be centrifuged.

               11.4.1.5      Determine the total solids content of the sample using the procedure  in
                             Appendix A.

       11.4.2 Determination of total recoverable analytes in sludge samples containing estimated total
               suspended solids < 1% (w/v).

               11.4.2.1      Transfer  100 mL of well-mixed sample to a 250 mL Griffin  beaker.

               11.4.2.2      Add 3 mL of concentrated HNO3 and place the beaker on a hot plate.
                             Heat the  sample and cautiously evaporate to a volume of 5 mL. If the
                             sample contains a large amount of dissolved solids, adjust this volume
                             upwards to prevent the sample from going to dryness. Remove the beaker
                             from the  hot plate and allow the sample to cool. Add 3 mL of
                             concentrated HNO3, cover with a watch glass and gently reflux the sample
                             until the sample is completely digested or no further changes in
                             appearance occur, adding additional aliquots of acid, if necessary, to
                             prevent the sample from going to dryness.  Remove the watch glass and
                             reduce the sample volume to 3 mL, again adjusting upwards if necessary.
Draft, January 2001                                                                                31

-------
Method 200.9
               11.4.2.2      Cool the beaker, then add 10 mL of reagent water and 4 mL of (1:1) HC1
                              to the sample and reflux for 15 minutes.  Cool the sample and dilute to
                              100 mL with reagent water. Any remaining solid material should be
                              allowed to settle, or an aliquot of the final sample volume may be
                              centrifuged.

               11.4.2.3      Determine the total solids content of the sample using the procedure in
                              Appendix A.

11.5   Sample analysis.

        11.5.1 Inspect the graphite furnace, the sample uptake system, and autosampler injector for any
               problems that would affect instrument performance. If necessary, clean the system and
               replace the graphite tube and/or platform.

        11.5.2 Configure the instrument.

               11.5.2.1      Specific wavelengths and instrument operating conditions are listed in
                              Table 3. However, because of differences among makes and models of
                              spectrophotometers and electrothermal furnace devices, the actual
                              instrument conditions selected may vary from those listed.

               11.5.2.2      Prior to the use of this method, instrument operating conditions must be
                              optimized. An analyst should follow the instructions provided by the
                              manufacturer while using the conditions listed in Table 3  as a guide. Of
                              particular importance is the determination of the charring temperature
                              limit for each analyte.  This limit is the furnace temperature setting when
                              a loss in analyte will occur prior to atomization.  This limit should be
                              determined by  conducting char temperature profiles for each analyte and
                              when necessary, in the matrix of question.  The charring temperature
                              selected should minimize background absorbance while providing some
                              furnace temperature  variation without loss of analyte. For routine
                              analyses, the charring temperature is set typically to at least 100C below
                              this limit.  Optimum conditions  should provide the  lowest reliable MDLs
                              and be  similar to those listed in  Table 1 (to be  confirmed during
                              collaborative validation study).  Once optimum operating conditions have
                              been determined, they should be recorded and  available for daily
                              reference.

               11.5.2.3      Configure the instrument system to optimize operating conditions for the
                              "direct  analysis" of drinking water with turbidity <1 NTU. Initiate the
                              data system and allow a period of not less than 15 minutes for instrument
                              and hollow cathode lamp warm up. If an EDL is to be used, allow 30
                              minutes for warm up.

               11.5.2.4      After the warm up period, but before  calibration, instrument stability must
                              be demonstrated by analyzing a standard solution with a concentration

32                                                                                 Draft, January 2001

-------
                                                                                       Method 200.9
                              20 times the ML, a minimum of five times. The resulting relative
                              standard deviation (RSD) of absorbance signals must be <5%.  If the
                              RSD is >5%, determine and correct the cause before calibrating the
                              instrument.

        11.5.3 Before using the method to analyze  samples, there must be data available documenting
               initial demonstration of laboratory capability. Required and acceptable data and
               procedures are described in Section 9.2. This data must be generated using the same
               instrument operating conditions and calibration routine (Sections 10.0 and 11.5.2)
               subsequently used for sample analysis. These documented data must be kept on file and be
               available for review by the data user.

        11.5.4 An autosampler must be used to introduce all solutions to the graphite furnace. Once the
               standard, sample or QC solution plus the matrix modifier is injected, the furnace controller
               completes furnace cycles and clean out periods as  programmed. Analyte signals must be
               integrated and collected as peak area measurements. Background absorbances,
               background corrected analyte signals, and determined analyte concentrations on all
               solutions must be displayed on  a CRT for immediate review by the analyst and be
               available as hard copy for documentation to be kept on file. The autosampler solution
               uptake system must be flushed with the rinse blank (Section 7.13.3) between injections.

        11.5.5 During the analysis of samples, a laboratory must  comply with the required quality control
               described in Sections 9.0.  Only during determination of dissolved analytes or "direct
               analysis" of drinking water with turbidity of <1 NTU is the sample digestion step of the
               method blank, OPR, MS, and MSD not required.

        11.5.6 Matrix interferences.

               11.5.6.1      For every new or unusual  matrix,  it is  highly recommended that an
                              inductively coupled plasma atomic emission spectrometer be used to
                              screen for high element concentrations whenever practical. Information
                              gained may reduce  potential damage to the atomic absorption instrument
                              and estimate which elements require graphite furnace analysis.

               11.5.6.2      When it is necessary to assess an  operative matrix interference (e.g.,
                              signal reduction due to high  dissolved solids), the test described in Section
                              9.7 is recommended.

        11.5.7 Sample analyte concentrations measured at 90% or more of the upper limit of calibration
               must either be diluted with acidified reagent water and  analyzed with concern for memory
               effects (Section 4.5), or be determined by another  approved test procedure that is less
               sensitive.  Samples with a background absorbance >1.0 must be appropriately diluted with
               acidified reagent water and analyzed again (Section 9.4.3.4).  If the method of standard
               additions is required, follow the instructions described  in Section 11.6.

        11.5.8 In order to meet or achieve lower MDLs than those listed in Table  1 for "direct analysis"
               of drinking water with turbidity <1 NTU, analyte preconcentration is required. This may


Draft, January 2001                                                                                   33

-------
Method 200.9
               be accomplished prior to sample introduction into the GFAA or with the use of multiple
               aliquot depositions on the GFAA platform or associated delayed atomization device.
               When using multiple depositions, the same number of equal volume aliquots of either the
               calibration standards or acid preserved samples must be deposited prior to atomization.
               Following each deposition, the drying cycle must be completed before beginning the next
               deposition.  Matrix modifier must be added along with each deposition and the total
               volume of each deposition must not exceed the instrument recommended capacity of the
               delayed atomization device. To reduce analysis time, the minimum number of depositions
               required to achieve the desired analytical result should be used.  Use of this multiple
               deposition technique for the "direct analysis" of drinking water must be completed using
               optimized instrument operating conditions (Section 11.5.2) and must comply with the
               method requirements described in Section 9.2.  (See Table 3 for information and data on
               the determination of arsenic by this procedure).

        11.5.9 Report data as directed in Section  12.0.

11.6   Standard additions-If the method of standard addition (MSA) is required, the following  procedure
        is recommended:

        11.6.1 The standard addition technique involves preparing new standards in the sample matrix by
               adding known amounts of standard to one or more aliquots of the processed sample
               solution (Reference  11).  This technique compensates for a sample constituent that
               enhances or depresses the analyte signal, thus producing a different slope from that of the
               calibration standards. It will not correct for additive interference, which causes a baseline
               shift.  The simplest version of this technique is the single-addition method. The procedure
               is as follows:  Two identical aliquots of the sample solution, each of volume V2,  are taken.
               To the first (aliquot  1) is added a small volume (V\) of a standard analyte solution of
               concentration C.  To the second (aliquot 2) is added the same volume (V\) of reagent
               matrix water.  It is best if V2 is much less than Vl to avoid excess dilution of the sample
               matrix. The analytical signals of aliquots 1 and 2 are measured and corrected for non-
               analyte signals. The unknown sample concentration (Cs) is calculated:
34                                                                                  Draft, January 2001

-------
                                                                                       Method 200.9
                                           Equation 7

                                              S2*Vl*C
                                      c =
                       where:
                      Cs = Sample concentration (mg/L)
                      C = Concentration of the standard solution (mg/L)
                      S1 = Signal for fortified aliquot
                      S2 = Signal for unfortified aliquot
                      V1 = Volume of the standard addition (L)
                      V2 = Volume of the sample aliquot used for MSA (L)
               If a separation or concentration step is required, the additions are made before separation
               or concentration and carried through the entire procedure. For the results from this
               technique to be valid, the following limitations apply:

                       1.      The calibration curve must be linear.

                       2.      The chemical form of the analyte added must respond in the same manner
                              as the analyte in the sample.

                       3.      The interference effect must be constant over the working range.

                       4.      The signal must be corrected for any additive interference.

12.0   Data Analysis and Calculations

12.1    Data should be reported in mg/L for aqueous samples and mg/kg  dry weight for sludge and solid
        samples.

12.2    For dissolved analytes in aqueous samples (Section  11.1) report the data generated directly from
        the instrument with allowance for sample dilution.  Do not report analyte concentrations below the
        MDL.

12.3    For total recoverable analytes in aqueous samples (Section 11.2), multiply solution analyte
        concentrations by the dilution factor (when a 100 mL aliquot is used to produce the 50 mL final
        solution, the dilution factor will equal 0.5). Round the data to the tenths place and report the data
        in mg/L up to three significant figures.  If a different aliquot volume other than 100 mL is used for
        sample preparation, adjust the dilution factor accordingly.  Also,  account for any additional
        dilution of the prepared sample solution needed to complete the determination of analytes exceeding
        the upper limit of the calibration curve. Do not report data below the  determined analyte MDL
        concentration or below an adjusted detection limit reflecting smaller sample aliquots used in
        processing or additional dilutions required to complete the analysis.

Draft, January 2001                                                                                  35

-------
Method 200.9
12.4  For total recoverable analytes in solid and sludge samples (Sections 11.3 and 11.4), round the
       solution analyte concentrations (mg/L) to the tenths place. Report the data up to three significant
       figures as mg/kg dry-weight basis unless specified otherwise by the program or data user.
       Calculate the concentration using Equation 8. Do not report analyte data below the solids MDL.

                                          Equation 8

                                             C*V*D

                                       GS=     w

               where:
                      Cs = Sample concentration (mg/kg, dry-weight basis)
                      C = Concentration in the extract (mg/L)
                      V = Volume of ex.tract (L, 100mL = 0.1 L)
                      D = Dilution factor (undiluted = 1)
	W = Weight of sample aliquot extracted (kg, 1 g = 0.001 kg)	

12.5  To report percent solids in solid and sludge samples, use the procedure given in Appendix A.

12.6  The QC data obtained during the analyses provide an indication of the quality of the sample data
       and should be provided with the sample results.

13.0  Method  Performance

13.1  Instrument operating conditions used for single laboratory application of the method and resulting
       MDLs are listed in Table 1.

13.2  Method performance criteria is given in Table 2 (to be determined in validation study).

14.0  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. 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  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 Relations and Science
       Policy," 1155 16th Street N.W., Washington, D.C. 20036, (202) 872-4477.
36                                                                                Draft, January 2001

-------
                                                                                     Method 200.9
15.0  Waste Management

15.1   The Environmental Protection Agency requires that laboratory waste management practices be
       conducted consistent with all applicable rule and regulations.  The Agency urges laboratories to
       protect the air, water, and land by minimizing and controlling all releases from hoods and bench
       operations, by complying discharge permit requirements 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 the Section 14.2.

16.0  References

       1.     U.S.  Environmental Protection Agency. Method 200.9, Determination of Trace Elements
              by Stabilized Temperature Graphite Furnace Atomic Absorption Spectrometry, Revision
              1.2,  1991.

       2.     Creed, J.T., T.D. Martin, L.B. Lobring and J.W. O'Dell. Environ.  Sci. Techno!.,
              26:102-106, 1992.

       3.     Waltz, B., G.  Schlemmar and J.R.  Mudakavi.  JAAS.  3, 695,  1988.

       4.     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, Aug. 1977.

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

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

       7.     Proposed OSHA Safety and Health Standards, Laboratories, Occupational Safety and
              Health Administration,  Federal Register, July 24, 1986.

       8.     Rohrbough, W.G. et al. Reagent Chemicals, American  Chemical Society Specifications,
              7th edition. American Chemical Society, Washington, D.C., 1986.

       9.     American Society for Testing and Materials. Standard  Specification  for Reagent Water,
              D1193-77. Annual  Book of ASTM Standards, Vol.  11.01. Philadelphia, PA, 1991.

       10.    Code of Federal Regulation 40. Pt. 136, Appendix B.

       11.    Winefordner, J.D., Trace Analysis:  Spectroscopic Methods for Elements, Chemical
              Analysis, Vol. 46, pp.  41.
Draft, January 2001                                                                                37

-------
Method 200.9
        12.     Deming, S.N., and S.L. Morgan. Experimental Design for Quality and Productivity in
               Research, Development, and Manufacturing, Part III, pp 119-123. Short course
               publication by Statistical Designs, 994 Rowlett, Suite 6, Houston TX 77075, 1989.
38                                                                                 Draft, January 2001

-------
                                                                            Method 200.9
17.0 Tables, Diagrams,  Flow Charts, and Validation Data




Table 1: MDLs and MLs of the method (to be determined during collaborative validation study).



Table 2: Performance criteria of the method (to be determined during collaborative validation study).
Draft, January 2001                                                                       39

-------
Method 200.9
TABLE 3.
RECOMMENDED
GRAPHITE FURNACE
OPERATING
CONDITIONS
AND RECOMMENDED MATRIX MODIFIER1 3

Element
Ag
Al
As7
Be
Cd
Co
Cr
Cu
Fe
Mn
Ni
Pb
Sb7
Se7
Sn7
Tl

Wavelength
328.1
309.3
193.7
234.9
228.8
242.5
357.9
324.8
248.3
279.5
232.0
283.3
217.6
196.0
286.3
276.8

Slit
0.7
0.7
0.7
0.7
0.7
0.2
0.7
0.7
0.2
0.2
0.2
0.7
0.7
2.0
0.7
0.7
Temperature
Char
1000
1700
1300
1200
800
1400
1650
1300
1400
1400
1400
1250
1100
1000
1400s
1000

(C)5 Atom
1800
2600
2200
2500
1600
2500
26006
26006
2400
2200
2500
2000
2000
2000
2300
1600
MDL4
(^g/L)
0.59
7.89
0.5
0.02
0.05
0.7
0.1
0.7
-
0.3
0.6
0.7
0.8
0.6
1.7
0.7
             Matrix Modifier = 0.015 mg Pd + 0.01 mg Mg(NO3)2.

             A 5% H2 in Ar gas mix is used during the dry and char steps at 300 mL/min.  for all
             elements.

             A cool down step between the char and atomization is recommended.

             Obtained using a 20 i\L sample size and stop flow atomization.

             Actual char and atomization temperatures may vary from instrument to instrument and are
             best determined on an individual basis. The actual drying temperature may vary depending
             on the temperature of the water used to cool the furnace.

             A 7-s atomization is necessary to quantitatively remove the analyte from the graphite
             furnace.

             An electrodeless discharge lamp was used for this element.

             An additional low temperature (approximately 200 C) per char is recommended.

             Pd modifier was determined to have trace level contamination of this element.
40                                                                                 Draft, January 2001

-------
                                                                                   Method 200.9
         Appendix A: Total Solids in  Solid and Semisolid Matrices
1.0   Scope and Application

1.1    This procedure is applicable to the determination of total solids in such solid and semisolid samples
       as soils, sediments, biosolids (municipal sewage sludge) separated from water and wastewater
       treatment processes, and sludge cakes from vacuum filtration, centrifugation, or other biosolids
       dewatering processes.

1.2    This procedure is taken from EPA Method 1684: Total, Fixed, and Volatile Solids in Solid and
       Semi-Solid Matrices.

1.3    Method detection limits (MDLs) and minimum levels (MLs) have not been formally established for
       this draft procedure.  These values will be determined during the validation of Method 1684.

1.4    This procedure is performance based. The laboratory is permitted to omit any step or modify any
       procedure (e.g. to overcome interferences, to lower the cost of measurement), provided that all
       performance requirements in this procedure are met. Requirements  for establishing equivalency
       are given in Section 9.1.2 of Method 200.9.

1.5    Each laboratory that uses this procedure must demonstrate the ability to generate acceptable results
       using the procedure in Section 9.2.

2.0   Summary of Method

2.1    Sample aliquots of 25-50 g are dried at 103 C to 105 C to drive off water in the sample.

2.3    The mass of total solids in the sample is determined by comparing the mass of the sample before
       and after each drying step.

3.0   Definitions

3.1    Total Solids-The residue left in the vessel after evaporation of liquid from a sample and
       subsequent drying in an oven at 103 C to 105 C.

3.2    Additional definitions are given in Sections 3.0 of Method 200.9.

4.0   Interferences

4.1    Sampling, subsampling, and pipeting multi-phase samples may introduce serious errors (Reference
       13.1). Make and keep such samples homogeneous during transfer.  Use special handling to ensure
       sample integrity when subsampling. Mix small samples with a magnetic stirrer. If visible
       suspended solids are present, pipet with wide-bore pipets.  If part of a sample adheres to the
       sample container, intensive homogenization is required to ensure accurate results. When dried,
Draft, January 2001                                                                              41

-------
Method 200.9
       some samples form a crust that prevents evaporation; special handling such as extended drying
       times are required to deal with this. Avoid using a magnetic stirrer with samples containing
       magnetic particles.

4.2    The temperature and time of residue drying has an important bearing on results (Reference 1).
       Problems such as weight losses due to volatilization of organic matter, and evolution of gases from
       heat-induced chemical decomposition, weight gains due to oxidation, and confounding factors like
       mechanical occlusion of water and water of crystallization depend on temperature and time of
       heating. It is therefore essential that samples be dried at a uniform temperature, and for no longer
       than specified. Each sample requires close attention to desiccation after drying. Minimize the time
       the desiccator is open because moist air may enter and be absorbed by the samples.  Some samples
       may be stronger desiccants than those used in the desiccator and may take on water.

4.3    Residues dried at 103 C to 105 C may retain some bound water as water of crystallization or as
       water occluded in the interstices of crystals. They lose CO2 in the conversion of bicarbonate to
       carbonate. The residues usually lose only slight amounts  of organic matter by volatilization at this
       temperature. Because removal of occluded water is marginal at this temperature, attainment of
       constant weight may be very slow.

4.4    Results for residues high in oil or grease may  be questionable because of the difficulty of drying to
       constant weight in a reasonable time.

4.5    The determination of total solids is subject to  negative error due to loss of ammonium carbonate
       and volatile organic matter during the drying  step at 103 C to  105 C. Carefully observe specified
       ignition time and temperature to control losses of volatile inorganic salts if these are a problem.

5.0   Safety

5.1    Refer to Section 5.0 of Method 200.9 for safety precautions.

6.0   Equipment and Supplies

       NOTE: Brand names, suppliers, and part numbers are cited for illustrative purposes only.  No
       endorsement is implied. Equivalent performance may be achieved using equipment and
       materials other than those specified here, but demonstration of equivalent performance that
	meets the requirements of this method is the responsibility of the laboratory.	


6.1    Evaporating Dishes-Dishes of 100-mL capacity. The dishes may be made of porcelain (90-mm
       diameter), platinum, or high-silica glass.

6.2     Watch glass-Capable of covering the evaporating dishes (Section 6.1).

6.3    Steam bath.
42                                                                                 Draft, January 2001

-------
                                                                                    Method 200.9
6.4    Desiccator-Moisture concentration in the desiccator should be monitored by an instrumental
       indicator or with a color-indicator desiccant.

6.5    Drying oven-Thermostatically-controlled, capable of maintaining a uniform temperature of 103 C
       to 105 C throughout the drying chamber.

6.6    Analytical balance-Capable of weighing to 0.1 mg for samples having a mass up to 200 g.

6.7    Container handling apparatus-Gloves, tongs, or a suitable holder for moving and handling hot
       containers after drying.

6.8    Bottles-Glass or plastic bottles of a suitable size for sample collection.

6.9    Rubber gloves (Optional).

6.10  No. 7 Cork borer (Optional).

7.0   Reagents and Standards

7.1    Reagent water-Deionized, distilled, or otherwise purified water.

7.2    Sodium chloride-potassium hydrogen phthalate standard (NaCl-KHP).

       7.2.1  Dissolve 0.10 g sodium chloride (NaCl) in 500 mL reagent water. Mix to dissolve.

       7.2.2 Add 0.10 g potassium hydrogen phthalate (KHP) to the NaCl solution (Section 7.2.1) and
              mix.  If the KHP does not dissolve readily, warm the solution while mixing. Dilute to 1 L
              with reagent water. Store at 4C.  Assuming 100% volatility of the acid phthalate ion, this
              solution contains 200 mg/L total solids, 81.0 mg/L volatile solids, and 119 mg/L fixed
              solids.

8.0   Sample Collection, Preservation,  and Storage

8.1    Use resistant-glass or plastic bottles to collect sample for solids analysis, provided that the material
       in suspension does not adhere to container walls.  Sampling should be done  in accordance with
       Reference 13.2. Begin analysis as soon as possible after collection because of the impracticality of
       preserving the sample. Refrigerate the  sample at 4 C up to the time of analysis to minimize
       microbiological decomposition of solids. Preferably do not hold samples more than 24 hours.
       Under no circumstances should the sample be held more than seven days. Bring samples to room
       temperature before analysis.

9.0   Quality Control

9.1    Quality control requirements and requirements for performance-based methods are given in Section
       9.1 of Method 200.9.


Draft, January 2001                                                                               43

-------
Method 200.9
9.2     Initial demonstration of laboratory capability - The initial demonstration of laboratory capability is
        used to characterize laboratory performance and method detection limits.

        9.2.1  Method detection limit (MDL) - The method detection limit should be established for the
               analyte, using diluted NaCl-KHP standard (Section 7.2). To determine MDL values, take
               seven replicate aliquots of the diluted NaCl-KHP solution and process each aliquot
               through each step of the analytical method. Perform all calculations and report the
               concentration values in the appropriate units. MDLs should be determined every year or
               whenever a modification to the method or analytical system is made that will affect the
               method detection limit.

        9.2.2  Initial Precision and Recovery (IPR) - To establish the ability to generate acceptable preci-
               sion and accuracy, the analyst shall perform the following operations:

               9.2.2.1        Prepare four samples by diluting NaCl-KHP standard (Section 7.2) to 1-5
                              times the MDL. Using the procedures in Section 11,  analyze these
                              samples for total solids.

               9.2.2.2       Using the results of the four analyses, compute the average percent recov-
                              ery (x) and the standard deviation (s, Equation  1) of the percent recovery
                              for total solids.
Equation 1
Is-2-
 1
(I-2)
n
                                         \       n-\
               Where:
                       n = number of samples
                       x = % recovery in each sample
                       s = standard deviation
               9.2.2.3       Compare s and x with the corresponding limits for initial precision and
                              recovery in Table 2 (to be determined in validation study).  If s and x meet
                              the acceptance criteria, system performance is acceptable and analysis of
                              samples may begin. If, however, s exceeds the precision limit or x falls
                              outside the range for recovery, system performance is unacceptable.  In
                              this event, correct the problem, and repeat the test.

9.3     Laboratory blanks

        9.3.1  Prepare and analyze a laboratory blank initially (i.e. with the tests in Section 9.2) and with
               each analytical batch. The blank must be subjected to the same procedural steps as a
               sample, and will consist of approximately 25 g of reagent water.
44                                                                                   Draft, January 2001

-------
                                                                                      Method 200.9
       9.3.2  If material is detected in the blank at a concentration greater than the MDL (Section 1.3),
               analysis of samples must be halted until the source of contamination is eliminated and a
               new blank shows no evidence of contamination. All samples must be associated with an
               uncontaminated laboratory blank before the results may be reported for regulatory compli-
               ance purposes.

9.4    Ongoing Precision and Recovery

       9.4.1  Prepare an ongoing precision and recovery (OPR) solution identical to the IPR solution
               described in Section 9.2.2.1.

       9.4.2  An aliquot of the OPR solution must be analyzed with each sample batch (samples started
               through the sample preparation process (Section 11) on the same 12-hour shift, to a
               maximum of 20 samples).

       9.4.3  Compute the percent recovery of total solids in the OPR sample.

       9.4.4  Compare the results to the limits for ongoing recovery in Table 2 (to be determined in
               validation study). If the results meet the acceptance criteria, system performance is
               acceptable and analysis of blanks and samples may proceed. If, however, the recovery of
               total solids falls  outside of the range given, the analytical processes are not being
               performed properly. Correct the problem, reprepare the sample batch,  and repeat the  OPR
               test. All samples must be associated with an OPR analysis that passes acceptance criteria
               before the  sample results can be reported for regulatory compliance purposes.

       9.4.5  results that pass the specifications in Section 9.4.4 to IPR and previous OPR data. Update
               QC charts to form a graphic representation of continued laboratory performance. Develop
               a statement of laboratory accuracy for each analyte by calculating the average percent
               recovery (R) and the standard deviation of percent recovery (SR). Express the accuracy as
               a recovery interval from R-2SRto R+2SR. For example, if R=05% and SR=5%, the
               accuracy is 85-115%.

9.5    Duplicate analyses

       9.5.1  Ten percent of samples must be analyzed in duplicate. The duplicate analyses must be
               performed within the same sample batch (samples whose analysis is started within the
               same 12-hour period, to a maximum of 20 samples).

       9.5.2  The total solids of the duplicate samples must be within 10%.

10.0  Calibration and Standardization

10.1   Calibrate the analytical balance at 2 mg and 1000 mg using class "S" weights.

10.2   Calibration shall be within   10% (i.e. 0.2 mg) at 2 mg and  0.5% (i.e. 5 mg) at 1000 mg. If
       values are not within these limits, recalibrate the balance.

Draft, January 2001                                                                                 45

-------
Method 200.9
11.0  Procedure

11.1   Preparation of evaporating dishes-Heat dishes and watch glasses at 103 C to 105 C for 1 hour in
       an oven. Cool and store the dried equipment in a desiccator. Weigh each dish and watch glass
       prior to use (record combined weight as "Wdlsh").

11.2   Preparation of samples

       11.2.1 Fluid samples-If the sample contains enough moisture to flow readily, stir to homogenize,
               place a 25 to 50 g sample aliquot on the prepared evaporating dish.  If the sample is to be
               analyzed in duplicate, the mass of the two aliquots may not differ by more than 10%.
               Spread each sample so that it is evenly distributed over the evaporating dish. Evaporate the
               samples to dryness on a steam bath. Cover each sample with a watch glass, and weigh
               (record weight as "Wsample").

       NOTE: Weigh wet samples quickly because wet samples tend to lose weight by evaporation.
	Samples should be weighed immediately after aliquots are prepared.	
       11.2.2 Solid samples-If the sample consists of discrete pieces of solid material (dewatered
               sludge, for example), take cores from each piece with a No. 7 cork borer or pulverize the
               entire sample coarsely on a clean surface by hand, using rubber gloves.  Place a 25 to 50 g
               sample aliquot of the pulverized sample on the prepared evaporating dish.  If the sample is
               to be analyzed in duplicate, the mass of the two aliquots may not differ by more than 10%.
               Spread each sample so that it is evenly distributed over the evaporating dish. Cover each
               sample with a watch glass, and weigh  (record weight as "Wsample").

11.3  Dry the samples at 103 C to 105 C for a minimum of 12 hours, cool to balance temperature in an
       individual desiccator containing fresh desiccant, and weigh.  Heat the residue again for 1 hour, cool
       it to balance temperature in a desiccator, and weigh. Repeat this heating, cooling, desiccating, and
       weighing procedure until the weight change is  less than 5% or 50 mg, whichever is less. Record
       the final weight as "Wtotal."

       NOTE: It is imperative that dried samples weighed quickly since residues often are very
       hygroscopic and rapidly absorb moisture from the air. Samples must remain in the dessicator
	until the analyst is ready to weigh  them.	
12.0  Data Analysis and Calculations

12.1   Calculate the % solids or the mg solids/kg sludge for total solids (Equation 2).
46                                                                                Draft, January 2001

-------
                                                                                   Method 200.9
                                         Equation 2
                             % total solids = ^	 * 100
                                          IJ/    	 I/i/
                                          "sample  "dish
                             or
                             mg total solids   W. ., - W,.,
                               ,71,	=  u      u  * 1,000,000
                               kg sludge     Wsample - Wdish


                     Where:
                             Wdlsh=Weightofdish (mg)
                             Wsample=Weight of wet sample and dish (mg)
                     	Wtotai=Weight of dried residue and dish (mg)
12.2   Sample results should be reported as % solids or mg/kg to three significant figures. Report results
       below the ML as < the ML, or as required by the permitting authority or in the permit.

13.0  Method Performance

13.1   Method performance (MDL and quality control acceptance criteria) will be determined during the
       multi-lab validation of this method.

13.2   Total solids duplicate determinations must agree within 10% to be reported for permitting
       purposes.  If duplicate samples do not meet this criteria, the problem must be discovered and the
       sample must be run over.

14.0  Pollution Prevention

14.2   Pollution prevention details are given in Section 14 of Method 200.9.

15.0  Waste Management

15.1   Waste management details are given in Section 15 of Method 200.9.

16.0  References

16.1   "Standard Methods for the Examination of Water and Wastewater," 18th ed. and later revisions,
       American Public Health Association, 1015 15th Street NW, Washington,  DC 20005. 1-35:
       Section 1090 (Safety), 1992.

16.2   U.S. Environmental Protection Agency, 1992. Control of Pathogens and Vector Attraction in
       Sewage Sludge.  Publ 625/R-92/013.  Office of Research and Development, Washington, DC.
Draft, January 2001                                                                             47

-------
Method 200.9
17.0  Tables, Diagrams, Flowcharts, and Validation Data

17.1  Tables containing method requirements for QA/QC will be added after the validation study has
      been performed.
48                                                                     Draft, January 2001

-------