analyze at least one LRB (Section 7.10.2) with each batch of 20 or
fewer samples of the same matrix. LRB data are used to assess
contamination from the laboratory environment. LRB values that
exceed the MDL indicate laboratory or reagent contamination should
be suspected. When LRB values constitute 10% or more of the analyte
level determined for a sample or is 2.2 times the analyte MDL
whichever is greater, fresh aliquots of the samples must be prepared
and analyzed again for the affected analytes after the source of
contamination has been corrected and acceptable LRB values have been
obtained.
    9.3.2 Laboratory fortified blank (LFB)--The laboratory must
analyze at least one LFB (Section 7.10.3) with each batch of
samples. Calculate accuracy as percent recovery using the following
equation:
[GRAPHIC] [TIFF OMITTED] TR18MY12.002

Where:

R = percent recovery
LFB = laboratory fortified blank
LRB = laboratory reagent blank
s = concentration equivalent of analyte added to fortify the LBR
solution

    If the recovery of any analyte falls outside the required
control limits of 85-115%, that analyte is judged out of control,
and the source of the problem should be identified and resolved
before continuing analyses.
    9.3.3 The laboratory must use LFB analyses data to assess
laboratory performance against the required control limits of 85-
115% (Section 9.3.2). When sufficient internal performance data
become available (usually a minimum of 20-30 analyses), optional
control limits can be developed from the mean percent recovery (x)
and the standard deviation (S) of the mean percent recovery. These
data can be used to establish the upper and lower control limits as
follows:

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

    The optional control limits must be equal to or better than the
required control limits of 85-115%. After each five to 10 new
recovery measurements, new control limits can be calculated using
only the most recent 20-30 data points. Also, the standard deviation
(S) data should be used to establish an on-going precision statement
for the level of concentrations included in the LFB. These data must
be kept on file and be available for review.
    9.3.4 Instrument performance check (IPC) solution--For all
determinations the laboratory must analyze the IPC solution (Section
7.11) and a calibration blank immediately following daily
calibration, after every 10th sample (or more frequently, if
required) and at the end of the sample run. Analysis of the
calibration blank should always be < the analyte IDL, but greater
than the lower 3-sigma control limit of the calibration blank.
Analysis of the IPC solution immediately following calibration must
verify that the instrument is within 5% of calibration with a
relative standard deviation <3% from replicate integrations 4.
Subsequent analyses of the IPC solution must be within 10% of
calibration. If the calibration cannot be verified within the
specified limits, reanalyze either or both the IPC solution and the
calibration blank. If the second analysis of the IPC solution or the
calibration blank confirm calibration to be outside the limits,
sample analysis must be discontinued, the cause determined,
corrected and/or the instrument recalibrated. All samples following
the last acceptable IPC solution must be reanalyzed. The analysis
data of the calibration blank and IPC solution must be kept on file
with the sample analyses data.
    9.3.5 Spectral interference check (SIC) solution--For all
determinations the laboratory must periodically verify the
interelement spectral interference correction routine by analyzing
SIC solutions. The preparation and required periodic analysis of SIC
solutions and test criteria for verifying the interelement
interference correction routine are given in Section 7.13. Special
cases where on-going verification is required are described in
Section 7.14.
    9.4 Assessing Analyte Recovery and Data Quality.
    9.4.1 Sample homogeneity and the chemical nature of the sample
matrix can affect analyte recovery and the quality of the data.
Taking separate aliquots from the sample for replicate and fortified
analyses can in some cases assess the effect. Unless otherwise
specified by the data user, laboratory or program, the following
laboratory fortified matrix (LFM) procedure (Section 9.4.2) is
required. Also, other tests such as the analyte addition test
(Section 9.5.1) and sample dilution test (Section 9.5.2) can
indicate if matrix effects are operative.
    9.4.2 The laboratory must add a known amount of each analyte to
a minimum of 10% of the routine samples. In each case the LFM
aliquot must be a duplicate of the aliquot used for sample analysis
and for total recoverable determinations added prior to sample
preparation. For water samples, the added analyte concentration must
be the same as that used in the laboratory fortified blank (Section
7.10.3). For solid samples, however, 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 0.1L/0.001kg = 100, Section 12.5).
(For notes on Ag, Ba, and Sn see Sections 1.7 and 1.8.) Over time,
samples from all routine sample sources should be fortified.
    Note: The concentration of calcium, magnesium, sodium and
strontium in environmental waters, along with iron and aluminum in
solids can vary greatly and are not necessarily predictable.
Fortifying these analytes in routine samples at the same
concentration used for the LFB may prove to be of little use in
assessing data quality for these analytes. For these analytes sample
dilution and reanalysis using the criteria given in Section 9.5.2 is
recommended. 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 affect the analysis.
    9.4.3 Calculate the percent recovery for each analyte, corrected
for background concentrations measured in the unfortified sample,
and compare these values to the designated LFM recovery range of 70-
130% or a 3-sigma recovery range calculated from the regression
equations given in Table 9.\16\ Recovery calculations are not
required if the concentration added is less than 30% of the sample
background concentration. Percent recovery may be calculated in
units appropriate to the matrix, using the following equation:
[GRAPHIC] [TIFF OMITTED] TR18MY12.003

Where:

R = percent recovery
Cs = fortified sample concentration
C = sample background concentration
s = concentration equivalent of analyte added to fortify the sample

    9.4.4 If the recovery of any analyte falls outside the
designated LFM recovery range, and the laboratory performance for
that analyte is shown to be in control (Section 9.3), the recovery
problem encountered with the fortified sample is judged to be matrix
related, not system related. 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
and analysis by method of standard addition or the use of an
internal standard(s) (Section 11.5) should be considered.
    9.4.5 Where reference materials are available, they should be
analyzed to provide additional performance data. The analysis of
reference samples is a valuable tool for demonstrating the ability
to perform the method acceptably. Reference materials containing
high concentrations of analytes can provide additional information
on the performance of the spectral interference correction routine.
    9.5 Assess the possible need for the method of standard
additions (MSA) or internal standard elements by the following
tests. Directions for using MSA or internal standard(s) are given in
Section 11.5.
    9.5.1 Analyte addition test: An analyte(s) standard added to a
portion of a prepared

sample, or its dilution, should be recovered to within 85% to 115%
of the known value. The analyte(s) addition should produce a minimum
level of 20 times and a maximum of 100 times the method detection
limit. If the analyte addition is <20% of the sample analyte
concentration, the following dilution test should be used. If
recovery of the analyte(s) is not within the specified limits, a
matrix effect should be suspected, and the associated data flagged
accordingly. The method of additions or the use of an appropriate
internal standard element may provide more accurate data.
    9.5.2 Dilution test: If the analyte concentration is
sufficiently high (minimally, a factor of 50 above the instrument
detection limit in the original solution but <90% of the linear
limit), an analysis of a 1 + 4 dilution should agree (after
correction for the fivefold dilution) within 10% of the original
determination. If not, a chemical or physical interference effect
should be suspected and the associated data flagged accordingly. The
method of standard additions or the use of an internal-standard
element may provide more accurate data for samples failing this
test.

10.0 Calibration and Standardization

    10.1 Specific wavelengths are listed in Table 1. Other
wavelengths may be substituted if they can provide the needed
sensitivity and are corrected for spectral interference. However,
because of the difference among various makes and models of
spectrometers, specific instrument operating conditions cannot be
given. The instrument and operating conditions utilized for
determination must be capable of providing data of acceptable
quality to the program and data user. The analyst should follow the
instructions provided by the instrument manufacturer unless other
conditions provide similar or better performance for a task.
Operating conditions for aqueous solutions usually vary from 1100-
1200 watts forward power, 15-16 mm viewing height, 15-19 L/min.
argon coolant flow, 0.6-1 L/min. argon aerosol flow, 1-1.8 mL/min.
sample pumping rate with a one minute preflush time and measurement
time near 1 s per wavelength peak (for sequential instruments) and
near 10 s per sample (for simultaneous instruments). Use of the Cu/
Mn intensity ratio at 324.754 nm and 257.610 nm (by adjusting the
argon aerosol flow) has been recommended as a way to achieve
repeatable interference correction factors.\17\
    10.2 Prior to using this method optimize the plasma operating
conditions. The following procedure is recommended for vertically
configured plasmas. The purpose of plasma optimization is to provide
a maximum signal-to-background ratio for the least sensitive element
in the analytical array. The use of a mass flow controller to
regulate the nebulizer gas flow rate greatly facilitates the
procedure.
    10.2.1 Ignite the plasma and select an appropriate incident rf
power with minimum reflected power. Allow the instrument to become
thermally stable before beginning. This usually requires at least 30
to 60 minutes of operation. While aspirating the 1000 [mu]g/mL
solution of yttrium (Section 7.8.32), follow the instrument
manufacturer's instructions and adjust the aerosol carrier gas flow
rate through the nebulizer so a definitive blue emission region of
the plasma extends approximately from 5-20 mm above the top of the
work coil.\18\ Record the nebulizer gas flow rate or pressure
setting for future reference.
    10.2.2 After establishing the nebulizer gas flow rate, determine
the solution uptake rate of the nebulizer in mL/min. by aspirating a
known volume calibration blank for a period of at least three
minutes. Divide the spent volume by the aspiration time (in minutes)
and record the uptake rate. Set the peristaltic pump to deliver the
uptake rate in a steady even flow.
    10.2.3 After horizontally aligning the plasma and/or optically
profiling the spectrometer, use the selected instrument conditions
from Sections 10.2.1 and 10.2.2, and aspirate the plasma solution
(Section 7.15), containing 10 [mu]g/mL each of As, Pb, Se and Tl.
Collect intensity data at the wavelength peak for each analyte at 1
mm intervals from 14-18 mm above the top of the work coil. (This
region of the plasma is commonly referred to as the analytical
zone.)\19\ Repeat the process using the calibration blank. Determine
the net signal to blank intensity ratio for each analyte for each
viewing height setting. Choose the height for viewing the plasma
that provides the largest intensity ratio for the least sensitive
element of the four analytes. If more than one position provides the
same ratio, select the position that provides the highest net
intensity counts for the least sensitive element or accept a
compromise position of the intensity ratios of all four analytes.
    10.2.4 The instrument operating condition finally selected as
being optimum should provide the lowest reliable instrument
detection limits and method detection limits. Refer to Tables 1 and
4 for comparison of IDLs and MDLs, respectively.
    10.2.5 If either the instrument operating conditions, such as
incident power and/or nebulizer gas flow rate are changed, or a new
torch injector tube having a different orifice i.d. is installed,
the plasma and plasma viewing height should be reoptimized.
    10.2.6 Before daily calibration and after the instrument warmup
period, the nebulizer gas flow must be reset to the determined
optimized flow. If a mass flow controller is being used, it should
be reset to the recorded optimized flow rate. In order to maintain
valid spectral interelement correction routines the nebulizer gas
flow rate should be the same from day-to-day (<2% change). The
change in signal intensity with a change in nebulizer gas flow rate
for both ``hard'' (Pb 220.353 nm) and ``soft'' (Cu 324.754) lines is
illustrated in Figure 1.
    10.3 Before using the procedure (Section 11.0) to analyze
samples, there must be data available documenting initial
demonstration of performance. The required data and procedure is
described in Section 9.2. This data must be generated using the same
instrument operating conditions and calibration routine (Section
11.4) to be used for sample analysis. These documented data must be
kept on file and be available for review by the data user.
    10.4 After completing the initial demonstration of performance,
but before analyzing samples, the laboratory must establish and
initially verify an interelement spectral interference correction
routine to be used during sample analysis. A general description
concerning spectral interference and the analytical requirements for
background correction and for correction of interelement spectral
interference in particular are given in Section 4.1. To determine
the appropriate location for background correction and to establish
the interelement interference correction routine, repeated spectral
scan about the analyte wavelength and repeated analyses of the
single element solutions may be required. Criteria for determining
an interelement spectral interference is an apparent positive or
negative concentration on the analyte that is outside the 3-sigma
control limits of the calibration blank for the analyte. (The upper-
control limit is the analyte IDL.) Once established, the entire
routine must be initially and periodically verified annually, or
whenever there is a change in instrument operating conditions
(Section 10.2.5). Only a portion of the correction routine must be
verified more frequently or on a daily basis. Test criteria and
required solutions are described in Section 7.13. Initial and
periodic verification data of the routine should be kept on file.
Special cases where on-going verification are required is described
in Section 7.14.

11.0 Procedure

11.1 Aqueous Sample Preparation--Dissolved Analytes

    11.1.1 For the determination of dissolved analytes in ground and
surface waters, pipet an aliquot (20 mL) of the filtered, acid
preserved sample into a 50 mL polypropylene centrifuge tube. Add an
appropriate volume of (1 + 1) nitric acid to adjust the acid
concentration of the aliquot to approximate a 1% (v[sol]v) nitric
acid solution (e.g., add 0.4 mL (1 + 1) HNO3 to a 20 mL
aliquot of sample). Cap the tube and mix. The sample is now ready
for analysis (Section 1.3). Allowance for sample dilution should be
made in the calculations. (If mercury is to be determined, a
separate aliquot must be additionally acidified to contain 1%
(v[sol]v) HCl to match the signal response of mercury in the
calibration standard and reduce memory interference effects. Section
1.9).
    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 the ``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 while making
allowance for sample dilution in the data calculation (Section 1.2).
For the determination of total recoverable analytes in all other
aqueous samples or for

preconcentrating drinking water samples prior to analysis follow the
procedure given in Sections 11.2.2 through 11.2.7.
    11.2.2 For the 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, acid preserved
sample to a 250 mL Griffin beaker (Sections 1.2, 1.3, 1.6, 1.7, 1.8,
and 1.9). (When necessary, smaller sample aliquot volumes may be
used.)
    Note: If the sample contains undissolved solids >1%, a well
mixed, acid preserved aliquot containing no more than 1 g
particulate 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) nitric acid and 1.0 mL of (1+1)
hydrochloric acid to the 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 [deg]C. (See the following note.) The beaker
should be covered with an elevated watch glass or other necessary
steps should be taken to prevent sample contamination from the fume
hood environment.
    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 85 [deg]C. (Once the
beaker is covered with a watch glass the temperature of the water
will rise to approximately 95 [deg]C.)
    11.2.4 Reduce the volume of the sample aliquot to about 20 mL by
gentle heating at 85 [deg]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 HCl-H2O azeotrope.)
    11.2.6 Allow the beaker to cool. Quantitatively transfer the
sample solution to a 50 mL volumetric flask, make to volume with
reagent water, stopper 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 the sample contains suspended
solids that would clog the nebulizer, a portion of the sample may be
filtered for their removal 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 the completed 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 tared weighing dish, weigh the sample and record the wet
weight (WW). (For samples with <35% moisture a 20 g portion is
sufficient. For samples with moisture >35% a larger aliquot 50-100 g
is required.) Dry the sample to a constant weight at 60 [deg]C and
record the dry weight (DW) for calculation of percent solids
(Section 12.6). (The sample is dried at 60 [deg]C to prevent the
loss of mercury and other possible volatile metallic compounds, to
facilitate sieving, and to ready the sample for grinding.)
    11.3.2 To achieve homogeneity, sieve the dried sample using a 5-
mesh polypropylene sieve and grind in a mortar and pestle. (The
sieve, mortar and pestle should be cleaned between samples.) From
the dried, ground material weigh accurately a representative 1.0
 0.01 g aliquot (W) of the sample and transfer to a 250
mL Phillips beaker for acid extraction (Sections 1.6, 1.7, 1.8, and
1.9).
    11.3.3 To the beaker add 4 mL of (1+1) HNO3 and 10 mL
of (1+4) HCl. Cover the lip of the beaker with a watch glass. Place
the beaker on a hot plate for reflux extraction of the analytes. The
hot plate should be located in a fume hood and previously adjusted
to provide a reflux temperature of approximately 95 [deg]C. (See the
following note.)
    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 85 [deg]C. (Once the
beaker is covered with a watch glass the temperature of the water
will rise to approximately 95 [deg]C.) Also, a block digester
capable of maintaining a temperature of 95 [deg]C and equipped with
250 mL constricted volumetric digestion tubes may be substituted for
the hot plate and conical beakers in the extraction step.
    11.3.4 Heat the sample and gently reflux for 30 minutes. Very
slight boiling may occur, however vigorous boiling must be avoided
to prevent loss of the HCl-H2O azeotrope. Some solution
evaporation will occur (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 the
nebulizer, a portion of the extract solution may be filtered for
their removal prior to analysis. However, care should be exercised
to avoid potential 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 the completed preparation.

11.4 Sample Analysis

    11.4.1 Prior to daily calibration of the instrument inspect the
sample introduction system including the nebulizer, torch, injector
tube and uptake tubing for salt deposits, dirt and debris that would
restrict solution flow and affect instrument performance. Clean the
system when needed or on a daily basis.
    11.4.2 Configure the instrument system to the selected power and
operating conditions as determined in Sections 10.1 and 10.2.
    11.4.3 The instrument must be allowed to become thermally stable
before calibration and analyses. This usually requires at least 30
to 60 minutes of operation. After instrument warmup, complete any
required optical profiling or alignment particular to the
instrument.
    11.4.4 For initial and daily operation calibrate the instrument
according to the instrument manufacturer's recommended procedures,
using mixed calibration standard solutions (Section 7.9) and the
calibration blank (Section 7.10.1). A peristaltic pump must be used
to introduce all solutions to the nebulizer. To allow equilibrium to
be reached in the plasma, aspirate all solutions for 30 seconds
after reaching the plasma before beginning integration of the
background corrected signal to accumulate data. When possible, use
the average value of replicate integration periods of the signal to
be correlated to the analyte concentration. Flush the system with
the rinse blank (Section 7.10.4) for a minimum of 60 seconds
(Section 4.4) between each standard. The calibration line should
consist of a minimum of a calibration blank and a high standard.
Replicates of the blank and 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.\20\
    11.4.5 After completion of the initial requirements of this
method (Sections 10.3 and 10.4), samples should be analyzed in the
same operational manner used in the calibration routine with the
rinse blank also being used between all sample solutions, LFBs,
LFMs, and check solutions (Section 7.10.4).
    11.4.6 During the analysis of samples, the laboratory must
comply with the required quality control described in Sections 9.3
and 9.4. Only for the determination of dissolved analytes or the
``direct analysis'' of drinking water with turbidity of <1 NTU is
the sample digestion step of the LRB, LFB, and LFM not required.
    11.4.7 Determined sample analyte concentrations that are 90% or
more of the upper limit of the analyte LDR must be diluted with
reagent water that has been acidified in the same manner as
calibration blank and reanalyzed (see Section 11.4.8). Also, for the
interelement spectral interference correction routines to remain
valid during sample analysis, the interferant concentration must not
exceed its LDR. If the interferant LDR is exceeded, sample dilution
with acidified reagent water and reanalysis is required. In these
circumstances analyte detection limits are raised and determination
by another approved test procedure that is either more sensitive
and/or interference free is recommended.

    11.4.8 When it is necessary to assess an operative matrix
interference (e.g., signal reduction due to high dissolved solids),
the tests described in Section 9.5 are recommended.
    11.4.9 Report data as directed in Section 12.0.
    11.5 If the method of standard additions (MSA) is used,
standards are added at one or more levels to portions of a prepared
sample. This technique \21\ compensates for enhancement or
depression of an analyte signal by a matrix. It will not correct for
additive interferences such as contamination, interelement
interferences, or baseline shifts. This technique is valid in the
linear range when the interference effect is constant over the
range, the added analyte responds the same as the endogenous
analyte, and the signal is corrected for additive interferences. The
simplest version of this technique is the single-addition method.
This procedure calls for two identical aliquots of the sample
solution to be taken. To the first aliquot, a small volume of
standard is added; while to the second aliquot, a volume of acid
blank is added equal to the standard addition. The sample
concentration is calculated by the following:
[GRAPHIC] [TIFF OMITTED] TR18MY12.004

Where:

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 (L) used for MSA

    For more than one fortified portion of the prepared sample,
linear regression analysis can be applied using a computer or
calculator program to obtain the concentration of the sample
solution. An alternative to using the method of standard additions
is use of the internal standard technique by adding one or more
elements (not in the samples and verified not to cause an
uncorrected interelement spectral interference) at the same
concentration (which is sufficient for optimum precision) to the
prepared samples (blanks and standards) that are affected the same
as the analytes by the sample matrix. Use the ratio of analyte
signal to the internal standard signal for calibration and
quantitation.

12.0 Data Analysis and Calculations

    12.1 Sample data should be reported in units of mg/L for aqueous
samples and mg/kg dry weight for solid samples.
    12.2 For dissolved aqueous analytes (Section 11.1) report the
data generated directly from the instrument with allowance for
sample dilution. Do not report analyte concentrations below the IDL.
    12.3 For total recoverable aqueous analytes (Section 11.2),
multiply solution analyte concentrations by the dilution factor 0.5,
when 100 mL aliquot is used to produce the 50 mL final solution, and
report data as instructed in Section 12.4. 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 90% or more of the LDR upper
limit. 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.
    12.4 For analytes with MDLs <0.01 mg/L, round the data values to
the thousandth place and report analyte concentrations up to three
significant figures. For analytes with MDLs <0.01 mg/L round the
data values to the 100th place and report analyte concentrations up
to three significant figures. Extract concentrations for solids data
should be rounded in a similar manner before calculations in Section
12.5 are performed.
    12.5 For total recoverable analytes in solid samples (Section
11.3), round the solution analyte concentrations (mg/L) as
instructed in Section 12.4. 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 the equation
below:
[GRAPHIC] [TIFF OMITTED] TR18MY12.005

Where:

C = Concentration in extract (mg/L)
V = Volume of extract (L, 100 mL = 0.1L)
D = Dilution factor (undiluted = 1)
W = Weight of sample aliquot extracted (g x 0.001 = kg)

    Do not report analyte data below the estimated solids MDL or an
adjusted MDL because of additional dilutions required to complete
the analysis.
    12.6 To report percent solids in solid samples (Section 11.3)
calculate as follows:
[GRAPHIC] [TIFF OMITTED] TR18MY12.006

Where:

DW = Sample weight (g) dried at 60 [ordm]C
WW = Sample weight (g) before drying

    Note: If the data user, program or laboratory requires that the
reported percent solids be determined by drying at 105 [deg]C,
repeat the procedure given in Section 11.3 using a separate portion
(>20 g) of the sample and dry to constant weight at 103-105 [deg]C.
    12.7 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 Listed in Table 4 are typical single laboratory total
recoverable MDLs determined for the recommended wavelengths using
simultaneous ICP-AES and the operating conditions given in Table 5.
The MDLs were determined in reagent blank matrix (best case
situation). PTFE beakers were used to avoid boron and silica
contamination from glassware with the final dilution to 50 mL
completed in polypropylene centrifuged tubes. The listed MDLs for
solids are estimates and were calculated from the aqueous MDL
determinations.
    13.2 Data obtained from single laboratory method testing are
summarized in Table 6 for five types of water samples consisting of
drinking water, surface water, ground water, and two wastewater
effluents. The data presented cover all analytes except cerium and
titanium. Samples were prepared using the procedure described in
Section 11.2. For each matrix, five replicate aliquots were
prepared, analyzed and the average of the five determinations used
to define the sample background concentration of each analyte. In
addition, two pairs of duplicates were fortified at different
concentration levels. For each method analyte, the sample background
concentration, mean percent recovery, standard deviation of the
percent recovery, and relative percent difference between the
duplicate fortified samples are listed in Table 6. The variance of
the five replicate sample background determinations is included in
the calculated standard deviation of the percent recovery when the
analyte concentration in the sample was greater than the MDL. The
tap and well waters were processed in Teflon and quartz beakers and
diluted in polypropylene centrifuged tubes. The nonuse of
borosilicate glassware is reflected in the precision and recovery
data for boron and silica in those two sample types.
    13.3 Data obtained from single laboratory method testing are
summarized in Table 7 for three solid samples consisting of EPA 884
Hazardous Soil, SRM 1645 River Sediment, and EPA 286 Electroplating
Sludge. Samples were prepared using the procedure described in
Section 11.3. For each method analyte, the sample background
concentration, mean percent recovery of the fortified additions, the
standard deviation of the percent

recovery, and relative percent difference between duplicate
additions were determined as described in Section 13.2. Data
presented are for all analytes except cerium, silica, and titanium.
Limited comparative data to other methods and SRM materials are
presented in Reference 23 of Section 16.0.
    13.4 Performance data for aqueous solutions independent of
sample preparation from a multilaboratory study are provided in
Table 8.\22\
    13.5 Listed in Table 9 are regression equations for precision
and bias for 25 analytes abstracted from EPA Method Study 27, a
multilaboratory validation study of Method 200.7.\1\ These equations
were developed from data received from 12 laboratories using the
total recoverable sample preparation procedure on reagent water,
drinking water, surface water and three industrial effluents. For a
complete review and description of the study, see Reference 16 of
Section 16.0.

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. The EPA has established a preferred hierarchy
of environmental management techniques that places pollution
prevention as the management option of first choice. Whenever
feasible, laboratory personnel should use pollution prevention
techniques to address their waste generation (e.g., Section 7.8).
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 NW.,
Washington, DC 20036,<PHONE_NUMBER>.

15.0 Waste Management

    15.1 The Environmental Protection Agency requires that
laboratory waste management practices be conducted consistent with
all applicable rules and regulations. The Agency urges laboratories
to protect the air, water, and land by minimizing and controlling
all releases from hoods and bench operations, complying with the
letter and spirit of any sewer discharge permits 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. Inductively Coupled Plasma--
Atomic Emission Spectrometric Method for Trace Element Analysis of
Water and Wastes--Method 200.7, Dec. 1982. EPA-600/4-79-020, revised
March 1983.
2. U.S. Environmental Protection Agency. Inductively Coupled Plasma
Atomic Emission Spectroscopy Method 6010, SW-846 Test Methods for
Evaluating Solid Waste, 3rd Edition, 1986.
3. U.S. Environmental Protection Agency. Method 200.7: Determination of
Metals and Trace Elements in Water and Wastes by Inductively Coupled
Plasma--Atomic Emission Spectrometry, revision 3.3, EPA 600 4-91/010,
June 1991.
4. U.S. Environmental Protection Agency. Inductively Coupled Plasma--
Atomic Emission Spectrometry Method for the Analysis of Waters and
Solids, EMMC, July 1992.
5. Fassel, V.A. et al. Simultaneous Determination of Wear Metals in
Lubricating Oils by Inductively-Coupled Plasma Atomic Emission
Spectrometry. Anal. Chem. 48:516-519, 1976.
6. Merryfield, R.N. and R.C. Loyd. Simultaneous Determination of Metals
in Oil by Inductively Coupled Plasma Emission Spectrometry. Anal. Chem.
51:1965-1968, 1979.
7. Winge, R.K. et al. Inductively Coupled Plasma--Atomic Emission
Spectroscopy: An Atlas of Spectral Information, Physical Science Data
20. Elsevier Science Publishing, New York, New York, 1985.
8. Boumans, P.W.J.M. Line Coincidence Tables for Inductively Coupled
Plasma Atomic Emission Spectrometry, 2nd edition. Pergamon Press,
Oxford, United Kingdom, 1984.
9. 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. Available from the National
Technical Information Service (NTIS) as PB-277256.
10. OSHA Safety and Health Standards, General Industry, (29 CFR 1910),
Occupational Safety and Health Administration, OSHA 2206, (Revised,
January 1976).
11. Safety in Academic Chemistry Laboratories, American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
12. Proposed OSHA Safety and Health Standards, Laboratories,
Occupational Safety and Health Administration, Federal Register, July
24, 1986.
13. Rohrbough, W.G. et al. Reagent Chemicals, American Chemical Society
Specifications, 7th edition. American Chemical Society, Washington, DC,
1986.
14. American Society for Testing and Materials. Standard Specification
for Reagent Water, D1193-77. Annual Book of ASTM Standards, Vol. 11.01.
Philadelphia, PA, 1991.
15. Code of Federal Regulations 40, Ch. 1, Pt. 136 Appendix B.
16. Maxfield, R. and B. Mindak. EPA Method Study 27, Method 200.7 Trace
Metals by ICP, Nov. 1983. Available from National Technical Information
Service (NTIS) as PB 85-248-656.
17. Botto, R.I. Quality Assurance in Operating a Multielement ICP
Emission Spectrometer. Spectrochim. Acta, 39B(1):95-113, 1984.
18. Wallace, G.F., Some Factors Affecting the Performance of an ICP
Sample Introduction System. Atomic Spectroscopy, Vol. 4, p. 188-192,
1983.
19. Koirtyohann, S.R. et al. Nomenclature System for the Low-Power
Argon Inductively Coupled Plasma, Anal. Chem. 52:1965, 1980.
20. 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, 9941 Rowlett,
Suite 6, Houston, TX 77075, 1989.
21. Winefordner, J.D., Trace Analysis: Spectroscopic Methods for
Elements, Chemical Analysis, Vol. 46, pp. 41-42.
22. Jones, C.L. et al. An Interlaboratory Study of Inductively Coupled
Plasma Atomic Emission Spectroscopy Method 6010 and Digestion Method
3050. EPA-600/4-87-032, U.S. Environmental Protection Agency, Las
Vegas, Nevada, 1987.
23. Martin, T.D., E.R. Martin and SE. Long. Method 200.2: Sample
Preparation Procedure for Spectrochemical Analyses of Total Recoverable
Elements, EMSL ORD, USEPA, 1989.

17.0 Tables, Diagrams, Flowcharts, and Validation Data

            Table 1--Wavelengths, Estimated Instrument Detection Limits, and Recommended Calibration
----------------------------------------------------------------------------------------------------------------
                                                                                Estimated
                                                              Wavelength\a\       detection     Calibrate\c\  to
                          Analyte                                 (nm)        limit\b\ ([mu]g/       (mg/L)
                                                                                L)
----------------------------------------------------------------------------------------------------------------
Aluminum..................................................           308.215                45                10
Antimony..................................................           206.833                32                 5
Arsenic...................................................           193.759                53                10
Barium....................................................           493.409               2.3                 1
Beryllium.................................................           313.042              0.27                 1
Boron.....................................................           249.678               5.7                 1
Cadmium...................................................           226.502               3.4                 2
Calcium...................................................           315.887                30                10
Cerium....................................................           413.765                48                 2
Chromium..................................................           205.552               6.1                 5
Cobalt....................................................           228.616               7.0                 2
Copper....................................................           324.754               5.4                 2
Iron......................................................           259.940               6.2                10
Lead......................................................           220.353                42                10
Lithium...................................................           670.784           \d\ 3.7                 5
Magnesium.................................................           279.079                30                10
Manganese.................................................           257.610               1.4                 2
Mercury...................................................           194.227               2.5                 2
Molybdenum................................................           203.844                12                10
Nickel....................................................           231.604                15                 2
Phosphorus................................................           214.914                76                10
Potassium.................................................           766.491           \e\ 700                20
Selenium..................................................           196.090                75                 5
Silica (SiO2).............................................           251.611     \d\ 26 (SiO2)                10
Silver....................................................           328.068               7.0               0.5
Sodium....................................................           588.995                29                10
Strontium.................................................           421.552              0.77                 1
Thallium..................................................           190.864                40                 5
Tin.......................................................           189.980                25                 4
Titanium..................................................           334.941               3.8                10
Vanadium..................................................           292.402               7.5                 2
Zinc......................................................           213.856               1.8                 5
----------------------------------------------------------------------------------------------------------------
\a\ The wavelengths listed are recommended because of their sensitivity and overall acceptability. Other
  wavelengths may be substituted if they can provide the needed sensitivity and are treated with the same
  corrective techniques for spectral interference (see Section 4.1).
\b\ These estimated 3-sigma instrumental detection limits \16\ are provided only as a guide to instrumental
  limits. The method detection limits are sample dependent and may vary as the sample matrix varies. Detection
  limits for solids can be estimated by dividing these values by the grams extracted per liter, which depends
  upon the extraction procedure. Divide solution detection limits by 10 for 1 g extracted to 100 mL for solid
  detection limits.
\c\ Suggested concentration for instrument calibration.\2\ Other calibration limits in the linear ranges may be
  used.
\d\ Calculated from 2-sigma data.\5\
\e\ Highly dependent on operating conditions and plasma position.

   TABLE 2--On-Line Method Interelement Spectral Interferances Arising From Interferants at the 100 mg/L Level
----------------------------------------------------------------------------------------------------------------
                  Analyte                     Wavelength (nm)                     Interferant*
----------------------------------------------------------------------------------------------------------------
Ag.........................................           328.068  Ce, Ti, Mn
Al.........................................           308.215  V, Mo, Ce, Mn
As.........................................           193.759  V, Al, Co, Fe, Ni
B..........................................           249.678  None
Ba.........................................           493.409  None
Be.........................................           313.042  V, Ce
Ca.........................................           315.887  Co, Mo, Ce
Cd.........................................           226.502  Ni, Ti, Fe, Ce
Ce.........................................           413.765  None
Co.........................................           228.616  Ti, Ba, Cd, Ni, Cr, Mo, Ce
Cr.........................................           205.552  Be, Mo, Ni
Cu.........................................           324.754  Mo, Ti
Fe.........................................           259.940  None
Hg.........................................           194.227  V, Mo
K..........................................           766.491  None
Li.........................................           670.784  None
Mg.........................................           279.079  Ce
Mn.........................................           257.610  Ce
Mo.........................................           203.844  Ce
Na.........................................           588.995  None
Ni.........................................           231.604  Co, Tl
P..........................................           214.914  Cu, Mo
Pb.........................................           220.353  Co, Al, Ce, Cu, Ni, Ti, Fe
Sb.........................................           206.833  Cr, Mo, Sn, Ti, Ce, Fe
Se.........................................           196.099  Fe
SiO2.......................................           251.611  None
Sn.........................................           189.980  Mo, Ti, Fe, Mn, Si
Sr.........................................           421.552  None
Tl.........................................           190.864  Ti, Mo, Co, Ce, Al, V, Mn
Ti.........................................           334.941  None
V..........................................           292.402  Mo, Ti, Cr, Fe, Ce
Zn.........................................           213.856  Ni, Cu, Fe
----------------------------------------------------------------------------------------------------------------
* These on-line interferences from method analytes and titanium only were observed using an instrument with
  0.035 nm resolution (see Section 4.1.2). Interferant ranked by magnitude of intensity with the most severe
  interferant listed first in the row.

                                        TABLE 3--Mixed Standard Solutions
----------------------------------------------------------------------------------------------------------------
                 Solution                                                 Analytes
----------------------------------------------------------------------------------------------------------------
I.........................................  Ag, As, B, Ba, Ca, Cd, Cu, Mn, Sb, and Se
II........................................  K, Li, Mo, Na, Sr, and Ti
III.......................................  Co, P, V, and Ce
IV........................................  Al, Cr, Hg, SiO2, Sn, and Zn
V.........................................  Be, Fe, Mg, Ni, Pb, and Tl
----------------------------------------------------------------------------------------------------------------

        TABLE 4--Total Recoverable Method Detection Limits (MDL)
------------------------------------------------------------------------
                                  MDLs  Aqueous, mg/
             Analyte                    L\(1)\        Solids, mg/kg\(2)\
------------------------------------------------------------------------
Ag..............................               0.002                 0.3
Al..............................                0.02                   3
As..............................               0.008                   2
B...............................               0.003                  --
Ba..............................               0.001                 0.2
Be..............................              0.0003                 0.1
Ca..............................                0.01                   2
Cd..............................               0.001                 0.2
Ce..............................                0.02                   3
Co..............................               0.002                 0.4
Cr..............................               0.004                 0.8
Cu..............................               0.003                 0.5
Fe..............................               *0.03                   6
Hg..............................               0.007                   2
K...............................                 0.3                  60
Li..............................               0.001                 0.2
Mg..............................                0.02                   3
Mn..............................               0.001                 0.2
Mo..............................               0.004                   1

Na..............................                0.03                   6
Ni..............................               0.005                   1
P...............................                0.06                  12
Pb..............................                0.01                   2
Sb..............................               0.008                   2
Se..............................                0.02                   5
SiO2............................                0.02                  --
Sn..............................               0.007                   2
Sr..............................              0.0003                 0.1
Tl..............................               0.001                 0.2
Ti..............................                0.02                   3
V...............................               0.003                   1
Zn..............................               0.002                 0.3
------------------------------------------------------------------------
\(1)\ MDL concentrations are computed for original matrix with allowance
  for 2x sample preconcentration during preparation. Samples were
  processed in PTFE and diluted in 50-mL plastic centrifuge tubes.
\(2)\ Estimated, calculated from aqueous MDL determinations.
-- Boron not reported because of glassware contamination. Silica not
  determined in solid samples.
* Elevated value due to fume-hood contamination.

   TABLE 5--Inductively Coupled Plasma Instrument Operating Conditions
------------------------------------------------------------------------

------------------------------------------------------------------------
Incident rf power........................  1100 watts
Reflected rf power.......................  <5 watts
Viewing height above work coil...........  15 mm
Injector tube orifice i.d................  1 mm
Argon supply.............................  liquid argon
Argon pressure...........................  40 psi
Coolant argon flow rate..................  19 L/min.
Aerosol carrier argon flow rate..........  620 mL/min.
Auxiliary (plasma) argon flow rate.......  300 mL/min.
Sample uptake rate controlled to.........  1.2 mL/min.
------------------------------------------------------------------------

                                                Table 6--Precision and Recovery Data in Aqueous Matrices
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Average                                             Average
              Analyte                   Sample     Low spike   recovery  R     S (R)         RPD       High spike  recovery  R     S (R)         RPD
                                     conc.  mg/L      mg/L         (%)                                    mg/L         (%)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Tap Water
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag.................................       <0.002         0.05           95          0.7          2.1          0.2           96          0.0          0.0
Al.................................        0.185         0.05           98          8.8          1.7          0.2          105          3.0          3.1
As.................................       <0.008         0.05          108          1.4          3.7          0.2          101          0.7          2.0
B..................................        0.023          0.1           98          0.2          0.0          0.4           98          0.2          0.5
Ba.................................        0.042         0.05          102          1.6          2.2          0.2           98          0.4          0.8
Be.................................      <0.0003         0.01          100          0.0          0.0          0.1           99          0.0          0.0
Ca.................................         35.2          5.0          101          8.8          1.7         20.0          103          2.0          0.9
Cd.................................       <0.001         0.01          105          3.5          9.5          0.1           98          0.0          0.0
Co.................................       <0.002         0.02          100          0.0          0.0          0.2           99          0.5          1.5
Cr.................................       <0.004         0.01          110          0.0          0.0          0.1          102          0.0          0.0
Cu.................................       <0.003         0.02          103          1.8          4.9          0.2          101          1.2          3.5
Fe.................................        0.008          0.1          106          1.0          1.8          0.4          105          0.3          0.5
Hg.................................       <0.007         0.05          103          0.7          1.9          0.2          100          0.4          1.0
K..................................         1.98          5.0          109          1.4          2.3          20.          107          0.7          1.7
Li.................................        0.006         0.02          103          6.9          3.8          0.2          110          1.9          4.4
Mg.................................         8.08          5.0          104          2.2          1.5         20.0          100          0.7          1.1
Mn.................................       <0.001         0.01          100          0.0          0.0          0.1           99          0.0          0.0
Mo.................................       <0.004         0.02           95          3.5         10.5          0.2          108          0.5          1.4
Na.................................         10.3          5.0           99          3.0          2.0         20.0          106          1.0          1.6
Ni.................................       <0.005         0.02          108          1.8          4.7          0.2          104          1.1          2.9
P..................................        0.045          0.1          102         13.1          9.4          0.4          104          3.2          1.3
Pb.................................        <0.01         0.05           95          0.7          2.1          0.2          100          0.2          0.5
Sb.................................       <0.008         0.05           99          0.7          2.0          0.2          102          0.7          2.0
Se.................................        <0.02          0.1           87          1.1          3.5          0.4           99          0.8          2.3
SiO2...............................          6.5          5.0          104          3.3          3.4         20.0           96          1.1          2.3
Sn.................................       <0.007         0.05          103          2.1          5.8          0.2          101          1.8          5.0
Sr.................................        0.181          0.1          102          3.3          2.1          0.4          105          0.8          1.0
Tl.................................        <0.02          0.1          101          3.9         10.9          0.4          101          0.1          0.3
V..................................       <0.003         0.05          101          0.7          2.0          0.2           99          0.2          0.5
Zn.................................        0.005         0.05          101          3.7          9.0          0.2           98          0.9          2.5
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Pond Water
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag.................................       <0.002         0.05           92          0.0          0.0          0.2           94          0.0          0.0

Al.................................        0.819          0.2           88         10.0          5.0          0.8          100          2.9          3.7
As.................................       <0.008         0.05          102          0.0          0.0          0.2           98          1.4          4.1
B..................................        0.034          0.1          111          8.9          6.9          0.4          103          2.0          0.0
Ba.................................        0.029         0.05           96          0.9          0.0          0.2           97          0.3          0.5
Be.................................      <0.0003         0.01           95          0.4          1.1          0.2           95          0.0          0.0
Ca.................................         53.9          5.0            *            *          0.7         20.0          100          2.0          1.5
Cd.................................       <0.001         0.01          107          0.0          0.0          0.1           97          0.0          0.0
Co.................................       <0.002         0.02          100          2.7          7.5          0.2           97          0.7          2.1
Cr.................................       <0.004         0.01          105          3.5          9.5          0.1          103          1.1          2.9
Cu.................................       <0.003         0.02           98          2.1          4.4          0.2          100          0.5          1.5
Fe.................................        0.875          0.2           95          8.9          2.8          0.8           97          3.2          3.6
Hg.................................       <0.007         0.05           97          3.5         10.3          0.2           98          0.0          0.0
K..................................         2.48          5.0          106          0.3          0.1         20.0          103          0.2          0.4
Li.................................       <0.001         0.02          110          0.0          0.0          0.2          106          0.2          0.5
Mg.................................         10.8          5.0          102          0.5          0.0         20.0           96          0.7          1.3
Mn.................................        0.632         0.01            *            *          0.2          0.1           97          2.3          0.3
Mo.................................       <0.004         0.02          105          3.5          9.5          0.2          103          0.4          1.0
Na.................................         17.8          5.0          103          1.3          0.4         20.0           94          0.3          0.0
Ni.................................       <0.005         0.02           96          5.6          9.1          0.2          100          0.7          1.5
P..................................        0.196          0.1           91         14.7          0.3          0.4          108          3.9          1.3
Pb.................................        <0.01         0.05           96          2.6          7.8          0.2          100          0.7          2.0
Sb.................................       <0.008         0.05          102          2.8          7.8          0.2          104          0.4          1.0
Se.................................        <0.02          0.1          104          2.1          5.8          0.4          103          1.6          4.4
SiO2...............................         7.83          5.0          151          1.6          1.3         20.0          117          0.4          0.6
Sn.................................       <0.007         0.05           98          0.0          0.0          0.2           99          1.1          3.0
Sr.................................        0.129          0.1          105          0.4          0.0          0.4           99          0.1          0.2
Tl.................................        <0.02          0.1          103          1.1          2.9          0.4           97          1.3          3.9
V..................................        0.003         0.05           94          0.4          0.0          0.2           98          0.1          0.0
Zn.................................        0.006         0.05           97          1.6          1.8          0.2           94          0.4          0.0
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Well Water
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag.................................       <0.002         0.05           97          0.7          2.1          0.2           96          0.2          0.5
Al.................................        0.036         0.05          107          7.6         10.1          0.2          101          1.1          0.8
As.................................       <0.008         0.05          107          0.7          1.9          0.2          104          0.4          1.0
B..................................        0.063          0.1           97          0.6          0.7          0.4           98          0.8          2.1
Ba.................................        0.102         0.05          102          3.0          0.0          0.2           99          0.9          1.0
Be.................................      <0.0003         0.01          100          0.0          0.0          0.1          100          0.0          0.0
Ca.................................         93.8          5.0            *            *          2.1         20.0          100          4.1          0.1
Cd.................................        0.002         0.01           90          0.0          0.0          0.1           96          0.0          0.0
Co.................................       <0.002         0.02           94          0.4          1.1          0.2           94          0.4          1.1
Cr.................................       <0.004         0.01          100          7.1         20.0          0.1          100          0.4          1.0
Cu.................................       <0.005         0.02          100          1.1          0.4          0.2           96          0.5          1.5
Fe.................................        0.042          0.1           99          2.3          1.4          0.4           97          1.4          3.3
Hg.................................       <0.007         0.05           94          2.8          8.5          0.2           93          1.2          3.8
K..................................         6.21          5.0           96          3.4          3.6         20.0          101          1.2          2.3
Li.................................        0.001         0.02          100          7.6          9.5          0.2          104          1.0          1.9
Mg.................................         24.5          5.0           95          5.6          0.3         20.0           93          1.6          1.2
Mn.................................         2.76         0.01            *            *          0.4          0.1            *            *          0.7
Mo.................................       <0.004         0.02          108          1.8          4.7          0.2          101          0.2          0.5
Na.................................         35.0          5.0          101         11.4          0.8         20.0          100          3.1          1.5
Ni.................................       <0.005         0.02          112          1.8          4.4          0.2           96          0.2          0.5
P..................................        0.197          0.1           95         12.7          1.9          0.4           98          3.4          0.9
Pb.................................        <0.01         0.05           87          4.9         16.1          0.2           95          0.2          0.5
Sb.................................       <0.008         0.05           98          2.8          8.2          0.2           99          1.4          4.0
Se.................................        <0.02          0.1          102          0.4          1.0          0.4           94          1.1          3.4
SiO2...............................         13.1          5.0           93          4.8          2.8         20.0           99          0.8          0.0
Sn.................................       <0.007         0.05           98          2.8          8.2          0.2           94          0.2          0.5
Sr.................................        0.274          0.1           94          5.7          2.7          0.4           95          1.7          2.2
Tl.................................        <0.02          0.1           92          0.4          1.1          0.4           95          1.1          3.2
V..................................       <0.003         0.05           98          0.0          0.0          0.2           99          0.4          1.0
Zn.................................        0.538         0.05            *            *          0.7          0.2           99          2.5          1.1
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Sewage Treatment Effluent
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag.................................        0.009         0.05           92          1.5          3.6          0.2           95          0.1          0.0
Al.................................         1.19         0.05            *            *          0.9          0.2          113         12.4          2.1
As.................................       <0.008         0.05           99          2.1          6.1          0.2           93          2.1          6.5
B..................................        0.226          0.1          217         16.3          9.5          0.4          119         13.1         20.9
Ba.................................        0.189         0.05           90          6.8          1.7          0.2           99          1.6          0.5

Be.................................      <0.0003         0.01           94          0.4          1.1          0.1          100          0.4          1.0
Ca.................................         87.9          5.0            *            *          0.6         20.0          101          3.7          0.0
Cd.................................        0.009         0.01           89          2.6          2.3          0.1           97          0.4          1.0
Co.................................        0.016         0.02           95          3.1          0.0          0.2           93          0.4          0.5
Cr.................................        0.128         0.01            *            *          1.5          0.1           97          2.4          2.7
Cu.................................        0.174         0.02           98         33.1          4.7          0.2           98          3.0          1.4
Fe.................................         1.28          0.1            *            *          2.8          0.4          111          7.0          0.6
Hg.................................       <0.007         0.05          102          1.4          3.9          0.2           98          0.5          1.5
K..................................         10.6          5.0          104          2.8          1.3         20.0          101          0.6          0.0
Li.................................        0.011         0.02          103          8.5          3.2          0.2          105          0.8          0.5
Mg.................................         22.7          5.0          100          4.4          0.0         20.0           92          1.1          0.2
Mn.................................        0.199         0.01            *            *          2.0          0.1          104          1.9          0.3
Mo.................................        0.125         0.02          110         21.2          6.8          0.2          102          1.3          0.9
Na.................................        0.236          5.0            *            *          0.0         20.0            *            *          0.4
Ni.................................        0.087         0.02          122         10.7          4.5          0.2           98          0.8          1.1
P..................................         4.71          0.1            *            *          2.6          0.4            *            *          1.4
Pb.................................        0.015         0.05           91          3.5          5.0          0.2           96          1.3          2.9
Sb.................................       <0.008         0.05           97          0.7          2.1          0.2          103          1.1          2.9
Se.................................        <0.02          0.1          108          3.9         10.0          0.4          101          2.6          7.2
SiO2...............................         16.7          5.0          124          4.0          0.9         20.0          108          1.1          0.8
Sn.................................        0.016         0.05           90          3.8          0.0          0.2           95          1.0          0.0
Sr.................................        0.515          0.1          103          6.4          0.5          0.4           96          1.6          0.2
Tl.................................        <0.02          0.1          105          0.4          1.0          0.4           95          0.0          0.0
V..................................        0.003         0.05           93          0.9          2.0          0.2           97          0.2          0.5
Zn.................................        0.160         0.05           98          3.3          1.9          0.2          101          1.0          1.4
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Industrial Effluent
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag.................................      <0.0003         0.05           88          0.0          0.0          0.2           84          0.9          3.0
Al.................................        0.054         0.05           88         11.7         12.2          0.2           90          3.9          8.1
As.................................        <0.02         0.05           82          2.8          9.8          0.2           88          0.5          1.7
B..................................         0.17          0.1          162         17.6         13.9          0.4           92          4.7          9.3
Ba.................................        0.083         0.05           86          8.2          1.6          0.2           85          2.3          2.4
Be.................................      <0.0006         0.01           94          0.4          1.1          0.1           82          1.4          4.9
Ca.................................          500          5.0            *            *          2.8         20.0            *            *          2.3
Cd.................................        0.008         0.01           85          4.7          6.1          0.1           82          1.4          4.4
Co.................................       <0.004         0.02           93          1.8          5.4          0.2           83          0.4          1.2
Cr.................................        0.165         0.01            *            *          4.5          0.1          106          6.6          5.6
Cu.................................        0.095         0.02           93         23.3          0.9          0.2           95          2.7          2.8
Fe.................................        0.315          0.1           88         16.4          1.0          0.4           99          6.5          8.0
Hg.................................        <0.01         0.05           87          0.7          2.3          0.2           86          0.4          1.2
K..................................         2.87          5.0          101          3.4          2.4         20.0          100          0.8          0.4
Li.................................        0.069         0.02          103         24.7          5.6          0.2          104          2.5          2.2
Mg.................................         6.84          5.0           87          3.1          0.0         20.0           87          0.9          1.2
Mn.................................        0.141         0.01            *            *          1.2          0.1           89          6.6          4.8
Mo.................................         1.27         0.02            *            *          0.0          0.2          100         15.0          2.7
Na.................................         1500          5.0            *            *          2.7         20.0            *            *          2.0
Ni.................................        0.014         0.02           98          4.4          3.0          0.2           87          0.5          1.1
P..................................        0.326          0.1          105         16.0          4.7          0.4           97          3.9          1.4
Pb.................................        0.251         0.05           80         19.9          1.4          0.2           88          5.0          0.9
Sb.................................         2.81         0.05            *            *          0.4          0.2            *            *          2.0
Se.................................        0.021          0.1          106          2.6          3.2          0.4          105          1.9          4.6
SiO2...............................         6.83          5.0           99          6.8          1.7         20.0          100          2.2          3.0
Sn.................................        <0.01         0.05           87          0.7          2.3          0.2           86          0.4          1.2
Sr.................................         6.54          0.1            *            *          2.0          0.4            *            *          2.7
Tl.................................        <0.03          0.1           87          1.8          5.8          0.4           84          1.1          3.6
V..................................       <0.005         0.05           90          1.4          4.4          0.2           84          1.1          3.6
Zn.................................        0.024         0.05           89          6.0          4.4          0.2           91          3.5          8.9
--------------------------------------------------------------------------------------------------------------------------------------------------------
S (R) Standard deviation of percent recovery.
RPD Relative percent difference between duplicate spike determinations.
< Sample concentration below established method detection limit.
* Spike concentration <10% of sample background concentration.

                                                 Table 7--Precision and Recovery Data in Solid Matrices
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                        Sample                   Average                                             Average
              Analyte                 conc.  mg/  Low + spike   recovery R     S (R)         RPD         High +     recovery R     S (R)         RPD
                                          kg         mg/kg         (%)                                spike mg/kg      (%)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            EPA Hazardous Soil 884
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag.................................          1.1           20           98          0.7          1.0          100           96          0.2          0.6
Al.................................         5080           20            *            *          7.2          100            *            *          5.4
As.................................          5.7           20           95          5.4         10.6          100           96          1.4          3.6
B..................................         20.4          100           93          2.7          5.3          400          100          2.1          5.5
Ba.................................          111           20           98         71.4         22.2          100           97         10.0          1.0
Be.................................         0.66           20           97          0.7          2.3          100           99          0.1          0.2
Ca.................................        85200            -            -            -            -            -            -            -            -
Cd.................................            2           20           93          0.7          1.0          100           94          0.2          0.4
Co.................................          5.5           20           96          3.5          7.7          100           93          0.8          2.1
Cr.................................         79.7           20           87         28.8         16.5          100          104          1.3          1.1
Cu.................................          113           20          110         16.2          4.4          100          104          4.0          4.2
Fe.................................        16500            -            -            -            -            -            -            -            -
Hg.................................         <1.4           10           92          2.5          7.7           40           98          0.0          0.0
K..................................          621          500          121          1.3          0.0         2000          107          0.9          1.8
Li.................................          6.7           10          113          3.5          4.4           40          106          0.6          0.6
Mg.................................        24400          500            *            *          8.4         2000            *            *         10.1
Mn.................................          343           20            *            *          8.5          100           95         11.0          1.6
Mo.................................          5.3           20           88          5.3         13.2          100           91          1.4          4.1
Na.................................          195          500          102          2.2          2.4         2000          100          1.5          3.7
Ni.................................         15.6           20          100          1.8          0.0          100           94          1.5          3.6
P..................................          595          500          106         13.4          8.0         2000          103          3.2          2.7
Pb.................................          145           20           88         51.8         17.9          100          108         15.6         17.4
Sb.................................          6.1           20           83          3.9          7.5          100           81          1.9          5.9
Se.................................           <5           20           79         14.7         52.4          100           99          0.7          2.1
Sn.................................         16.6           20           91         34.6          5.8           80          112          8.7          2.8
Sr.................................          102          100           84          9.6         10.8          400           94          2.5          4.6
Tl.................................           <4           20           92          4.8         14.6          100           91          1.5          4.6
V..................................         16.7           20          104          4.2          5.4          100           99          0.8          1.7
Zn.................................          131           20          103         31.2          7.3          100          104          7.2          6.4
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        EPA Electroplating Sludge 286
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag.................................            6           20           96          0.2          0.4          100           93          0.1          0.4
Al.................................         4980           20            *            *          4.4          100            *            *          5.6
As.................................           32           20           94          1.3          0.8          100           97          0.7          1.6
B..................................          210          100          113          2.0          1.6          400           98          1.9          3.5
Ba.................................         39.8           20            0          6.8          0.3          100            0          1.6          5.7
Be.................................         0.32           20           96          0.2          0.5          100          101          0.7          2.0
Ca.................................        48500            -            -            -            -            -            -            -            -
Cd.................................          108           20           98          2.5          0.8          100           96          0.5          0.5
Co.................................          5.9           20           93          2.9          5.7          100           93          0.6          1.5
Cr.................................         7580           20            *            *          0.7          100            *            *          1.3
Cu.................................          806           20            *            *          1.5          100           94          8.3          0.7
Fe.................................        31100            -            -            -            -            -            -            -            -
Hg.................................          6.1           10           90          2.5          4.0           40           97          1.7          4.3
K..................................         2390          500           75          8.3          4.0         2000           94          2.9          3.8
Li.................................          9.1           10          101          2.8          0.5           40          106          1.6          3.1
Mg.................................         1950          500          110          2.0          0.8         2000          108          2.3          3.2
Mn.................................          262           20            *            *          1.8          100           91          1.2          0.9
Mo.................................         13.2           20           92          2.1          2.9          100           92          0.3          0.0
Na.................................        73400          500            *            *          1.7         2000            *            *          1.4
Ni.................................          456           20            *            *          0.4          100           88          2.7          0.9
P..................................         9610          500            *            *          2.9         2000          114          7.4          3.4
Pb.................................         1420           20            *            *          2.1          100            *            *          1.3
Sb.................................           <2           20           76          0.9          3.3          100           75          2.8         10.7
Se.................................          6.3           20           86          9.0         16.6          100          103          1.6          2.7
Sn.................................         24.0           20           87          4.0          2.7           80           92          0.7          0.0
Sr.................................          145          100           90          8.1          8.1          400           93          2.4          4.6
Tl.................................           16           20           89          4.6          5.3          100           92          0.8          0.9
V..................................         21.7           20           95          1.2          1.0          100           96          0.4          0.9
Zn.................................        12500           20            *            *          0.8          100            *            *          0.8
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 NBS 1645 River Sediment
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ag.................................          1.6           20           92          0.4          1.0          100           96          0.3          0.9
Al.................................         5160           20            *            *          8.4          100            *            *          2.4
As.................................         62.8           20           89         14.4          9.7          100           97          2.9          5.0
B..................................         31.9          100          116          7.1         13.5          400           95          0.6          1.5
Ba.................................         54.8           20           95          6.1          2.8          100           98          1.2          1.3

Be.................................         0.72           20          101          0.4          1.0          100          103          1.4          3.9
Ca.................................        28000            -            -            -            -            -            -            -            -
Cd.................................          9.7           20          100          1.1          0.0          100          101          0.7          1.8
Co.................................          9.4           20           98          3.8          4.8          100           98          0.9          1.8
Cr.................................        28500           20            *            *          0.4          100            *            *          0.7
Cu.................................          109           20          115          8.5          0.0          100          102          1.8          1.0
Fe.................................        84800            -            -            -            -            -            -            -            -
Hg.................................          3.1           10           99          4.3          7.7           40           96          0.7          1.0
K..................................          452          500           98          4.1          2.0         2000          106          1.4          2.3
Li.................................          3.7           10          101          2.0          0.7           40          108          1.3          3.0
Mg.................................         6360          500            *            *          1.8         2000           93          2.7          1.0
Mn.................................          728           20            *            *          3.5          100           97         12.4          2.2
Mo.................................         17.9           20           97         12.5         18.5          100           98          0.6          0.0
Na.................................         1020          500           92          2.6          0.0         2000           97          1.1          1.7
Ni.................................         36.2           20           94          5.9          4.0          100          100          1.1          1.5
P..................................          553          500          102          1.4          0.9         2000          100          0.8          1.6
Pb.................................          707           20            *            *          0.8          100          103          5.9          0.4
Sb.................................         22.8           20           86          2.3          0.0          100           88          0.6          0.9
Se.................................          6.7           20          103         14.3         27.1          100           98          3.1          7.6
Sn.................................          309           20            *            *          1.0           80          101          7.9          2.7
Sr.................................          782          100           91         12.3          3.0          400           96          3.3          2.6
Tl.................................           <4           20           90          0.0          0.0          100           95          1.3          4.0
V..................................         20.1           20           89          5.4          5.8          100           98          0.7          0.0
Zn.................................         1640           20            *            *          1.8          100            *            *          1.1
--------------------------------------------------------------------------------------------------------------------------------------------------------
S (R) Standard deviation of percent recovery.
RPD Relative percent difference between duplicate spike determinations.
< Sample concentration below established method detection limit.
* Spike concentration <10% of sample background concentration.
- Not spiked.
+ Equivalent.

                  Table 8--ICP-AES Instrumental Precision and Accuracy for Aqueous Solutions a
----------------------------------------------------------------------------------------------------------------
                                          Mean conc.  (mg/                                       Accurace c  (%
                 Element                         L)                N b             RSD (%)         of Nominal)
----------------------------------------------------------------------------------------------------------------
Al......................................              14.8                 8               6.3               100
Sb......................................              15.1                 8               7.7               102
As......................................              14.7                 7               6.4                99
Ba......................................              3.66                 7               3.1                99
Be......................................              3.78                 8               5.8               102
Cd......................................              3.61                 8               7.0                97
Ca......................................              15.0                 8               7.4               101
Cr......................................              3.75                 8               8.2               101
Co......................................              3.52                 8               5.9                95
Cu......................................              3.58                 8               5.6                97
Fe......................................              14.8                 8               5.9               100
Pb......................................              14.4                 7               5.9                97
Mg......................................              14.1                 8               6.5                96
Mn......................................              3.70                 8               4.3               100
Mo......................................              3.70                 8               6.9               100
Ni......................................              3.70                 7               5.7               100
K.......................................              14.1                 8               6.6                95
Se......................................              15.3                 8               7.5               104
Na......................................              14.0                 8               4.2                95
Tl......................................              15.1                 7               8.5               102
V.......................................              3.51                 8               6.6                95
Zn......................................              3.57                 8               8.3               96
----------------------------------------------------------------------------------------------------------------
a These performance values are independent of sample preparation because the labs analyzed portions of the same
  solutions using sequential or simultaneous instruments.
b N = Number of measurements for mean and relative standard deviation (RSD).
c Accuracy is expressed as a percentage of the nominal value for each analyte in the acidified, multi-element
  solutions.

                            Table 9--Multilaboratory ICP Precision and Accuracy Data*
----------------------------------------------------------------------------------------------------------------
                                              Concentration
                  Analyte                        [mu]g/L              Total recoverable digestion [mu]/L
----------------------------------------------------------------------------------------------------------------
Aluminum...................................          69-4792  X = 0.9380 (C) + 22.1

                                             ...............  SR = 0.0481 (X) + 18.8
Antimony...................................          77-1406  0.8908 (C) + 0.9
                                             ...............  SR = 0.0682 (X) + 2.5
Arsenic....................................          69-1887  X = 1.0175 (C) + 3.9
                                             ...............  SR = 0.0643 (X) + 10.3
Barium.....................................            9-377  X = 0.8.80 (C) + 1.68
                                             ...............  SR = 0.0826 (X) + 3.54
Beryllium..................................           3-1906  X = 1.0177 (C) - 0.55
                                             ...............  SR = 0.0445 (X) - 0.10
Boron......................................          19-5189  X = 0.9676 (C) + 18.7
                                             ...............  SR = 0.0743 (X) + 21.1
Cadmium....................................           9-1943  X = 1.0137 (C) - 0.65
                                             ...............  SR = 0.0332 (X) + 0.90
Calcium....................................         17-47170  X = 0.9658 (C) + 0.8
                                             ...............  SR = 0.0327 (X) + 10.1
Chromium...................................          13-1406  X = 1.0049 (C) - 1.2
                                             ...............  SR = 0.0571 (X) + 1.0
Cobalt.....................................          17-2340  X = 0.9278 (C) + 1.5
                                             ...............  SR = 0.0407 (X) + 0.4
Copper.....................................           8-1887  X = 0.9647 (C) - 3.64
                                             ...............  SR = 0.0406 (X) + 0.96
Iron.......................................          13-9359  X = 0.9830 (C) + 5.7
                                             ...............  SR = 0.0790 (X) + 11.5
Lead.......................................          42-4717  X = 1.0056 (C) + 4.1
                                             ...............  SR = 0.0448 (X) + 3.5
Magnesium..................................         34-13868  X = 0.9879 (C) + 2.2
                                             ...............  SR = 0.0268 (X) + 8.1
Manganese..................................           4-1887  X = 0.9725 (C) + 0.07
                                             ...............  SR = 0.0400 (X) + 0.82
Molybdenum.................................          17-1830  X = 0.9707 (C) - 2.3
                                             ...............  SR = 0.0529 (X) + 2.1
Nickel.....................................         17-47170  X = 0.9869 (C) + 1.5
                                             ...............  SR = 0.0393 (X) + 2.2
Potassium..................................        347-14151  X = 0.9355 (C) - 183.1
                                             ...............  SR = 0.0329 (X) + 60.9
Selenium...................................          69-1415  X = 0.9737 (C) - 1.0
                                             ...............  SR = 0.0443 (X) + 6.6
Silicon....................................         189-9434  X = 0.9737 (C) - 22.6
                                             ...............  SR = 0.2133 (X) + 22.6
Silver.....................................            8-189  X = 0.3987 (C) + 8.25
                                             ...............  SR = 0.1836 (X) - 0.27
Sodium.....................................         35-47170  X = 1.0526 (C) + 26.7
                                             ...............  SR = 0.0884 (X) + 50.5
Thallium...................................          79-1434  X = 0.9238 (C) + 5.5
                                             ...............  SR = 0.0106 (X) + 48.0
Vanadium...................................          13-4698  X = 0.9551 (C) + 0.4
                                             ...............  SR = 0.0472 (X) + 0.5
Zinc.......................................           7-7076  X = 0.9500 (C) + 1.82
                                             ...............  SR = 0.0153 (X) + 7.78
----------------------------------------------------------------------------------------------------------------
\*\--Regression equations abstracted from Reference 16.
X = Mean Recovery, [mu]g/L.
C = True Value for the Concentration, [mu]g/L.
SR = Single-analyst Standard Deviation, [mu]g/L.

BILLING CODE 6560-50-P

[GRAPHIC] [TIFF OMITTED] TR18MY12.007

BILLING CODE 6560-50-C

0
9. Revise Appendix D to Part 136 to read as follows:

Appendix D to Part 136--Precision and Recovery Statements for Methods
for Measuring Metals

    Two selected methods from ``Methods for Chemical Analysis of
Water and Wastes,'' EPA-600/4-79-020 (1979) have been subjected to
interlaboratory method validation studies. The two selected methods
are for Thallium and Zinc. The following precision and recovery
statements are presented in this appendix and incorporated into Part
136:

Method 279.2

    For Thallium, Method 279.2 (Atomic Absorption, Furnace
Technique) replace the Precision and Accuracy Section statement with
the following:

Precision and Accuracy

    An interlaboratory study on metal analyses by this method was
conducted by the Quality Assurance Branch (QAB) of the

Environmental Monitoring Systems Laboratory--Cincinnati (EMSL-CI).
Synthetic concentrates containing various levels of this element
were added to reagent water, surface water, drinking water and three
effluents. These samples were digested by the total digestion
procedure, 4.1.3 in this manual. Results for the reagent water are
given below. Results for other water types and study details are
found in ``EPA Method Study 31, Trace Metals by Atomic Absorption
(Furnace Techniques),'' National Technical Information Service, 5285
Port Royal Road, Springfield, VA 22161 Order No. PB 86-121 704/AS,
by Copeland, F.R. and Maney, J.P., January 1986.
    For a concentration range of 10.00-252 [micro]g[sol]L

X = 0.8781(C) - 0.715
S = 0.1112(X) + 0.669
SR = 0.1005(X) + 0.241

Where:

C = True Value for the Concentration, [micro]g/L
X = Mean Recovery, [micro]g/L
S = Multi-laboratory Standard Deviation, [micro]g/L
SR = Single-analyst Standard Deviation, [micro]g/L

Method 289.2

    For Zinc, Method 289.2 (Atomic Absorption, Furnace Technique)
replace the Precision and Accuracy Section statement with the
following:

Precision and Accuracy

    An interlaboratory study on metal analyses by this method was
conducted by the Quality Assurance Branch (QAB) of the Environmental
Monitoring Systems Laboratory--Cincinnati (EMSL-CI). Synthetic
concentrates containing various levels of this element were added to
reagent water, surface water, drinking water and three effluents.
These samples were digested by the total digestion procedure, 4.1.3
in this manual. Results for the reagent water are given below.
Results for other water types and study details are found in ``EPA
Method Study 31, Trace Metals by Atomic Absorption (Furnace
Techniques),'' National Technical Information Service, 5285 Port
Royal Road, Springfield, VA 22161 Order No. PB 86-121 704/AS, by
Copeland, F.R. and Maney, J.P., January 1986.
    For a concentration range of 0.51-189 [micro]g[sol]L

X = 1.6710(C) + 1.485
S = 0.6740(X) - 0.342
SR = 0.3895(X)- 0.384

Where:

C = True Value for the Concentration, [micro]g[sol]L
X = Mean Recovery, [micro]g[sol]L
S = Multi-laboratory Standard Deviation, [micro]g[sol]L
SR = Single-analyst Standard Deviation, [micro]g[sol]L

PART 260--HAZARDOUS WASTE MANAGEMENT SYSTEM: GENERAL

0
10. The authority citation for Part 260 continues to read as follows:

     Authority:  42 U.S.C. 6905, 6912(a), 6921-6927, 6930, 6934,
6935, 6937, 6938, 6939, and 6974.

Subpart B--Definitions

0
11. Section 260.11 is amended by revising paragraph (c)(2) to read as
follows:

Sec.  260.11  References.

* * * * *
    (c) * * *
    (2) Method 1664, n-Hexane Extractable Material (HEM; Oil and
Grease) and Silica Gel Treated n-Hexane Extractable Material SGT-HEM;
Non-polar Material) by Extraction and Gravimetry:
    (i) Revision A, EPA-821-R-98-002, February 1999, IBR approved for
Part 261, Appendix IX.
    (ii) Revision B, EPA-821-R-10-001, February 2010, IBR approved for
Part 261, Appendix IX.
* * * * *

PART 423--STEAM ELECTRIC POWER GENERATING POINT SOURCE CATEGORY

0
12. The authority citation for Part 423 continues to read as follows:

    Authority:  Secs. 301; 304(b), (c), (e), and (g); 306(b) and
(c); 307(b) and (c); and 501, Clean Water Act (Federal Water
Pollution Control Act Amendments of 1972, as amended by Clean Water
Act of 1977) (the ``Act''; 33 U.S.C. 1311; 1314(b), (c), (e), and
(g); 1316(b) and (c); 1317(b) and (c); and 1361; 86 Stat. 816, Pub.
L. 92-500; 91 Stat. 1567, Pub. L. 95-217), unless otherwise noted.

0
13. Section 423.11 is amended by revising paragraphs (a) and (l) to
read as follows:

Sec.  423.11  Specialized definitions.

* * * * *
    (a) The term total residual chlorine (or total residual oxidants
for intake water with bromides) means the value obtained using any of
the ``chlorine--total residual'' methods in Table IB in 40 CFR
136.3(a), or other methods approved by the permitting authority.
* * * * *
    (l) The term free available chlorine means the value obtained using
any of the ``chlorine--free available'' methods in Table IB in 40 CFR
136.3(a) where the method has the capability of measuring free
available chlorine, or other methods approved by the permitting
authority.
* * * * *

PART 430--PULP, PAPER, AND PAPERBOARD POINT SOURCE CATEGORY

0
14. The authority citation for Part 430 continues to read as follows:

    Authority: Secs. 301, 304, 306, 307, 308, 402, and 501, Clean
Water Act as amended, (33 U.S.C. 1311, 1314, 1316, 1317, 1318, 1342,
and 1361) and Section 112 of the Clean Air Act, as amended (42
U.S.C. 7412).

0
15. Section 430.01 is amended by revising paragraph (a) and by adding
paragraphs (s) through (v) to read as follows:

Sec.  430.01  General definitions.

* * * * *
    (a) Adsorbable organic halides (AOX). A bulk parameter that
measures the total mass of chlorinated organic matter in water and
wastewater. The approved method of analysis for AOX is Method 1650,
which is available in Appendix A of this part, and online at http://water.epa.gov/scitech/methods/cwa/index.cfm.
* * * * *
    (s) TCDD. 2,3,7,8-tetrachlorodibenzo-p-dioxin. The approved method
of analysis for TCDD is Method 1613B, which is available in Appendix A
of this part, and online at http://water.epa.gov/scitech/methods/cwa/index.cfm.
    (t) TCDF. 2,3,7,8-tetrachlorodibenzofuran. The approved method of
analysis for TCDF is Method 1613B, which is available in Appendix A of
this part, and online at http://water.epa.gov/scitech/methods/cwa/index.cfm.
    (u) Chloroform. The approved methods of analysis for chloroform are
listed in Table IC at 40 CFR 136.3.
    (v) The approved method of analysis for the following chlorinated
phenolic compounds is Method 1653, which is available in Appendix A of
this part, and online at http://water.epa.gov/scitech/methods/cwa/index.cfm:
    (1) Trichlorosyringol.
    (2) 3,4,5-Trichlorocatechol.
    (3) 3,4,6-Trichlorocatechol.
    (4) 3,4,5-Trichloroguaiacol.
    (5) 3,4,6-Trichloroguaiacol.
    (6) 4,5,6-Trichloroguaiacol.
    (7) 2,4,5-Trichlorophenol.
    (8) 2,4,6-Trichlorophenol.
    (9) Tetrachlorocatechol.
    (10) Tetrachloroguaiacol.
    (11) 2,3,4,6-Tetrachlorophenol.
    (12) Pentachlorophenol.

PART 435--OIL AND GAS EXTRACTION POINT SOURCE CATEGORY

0
16. The authority citation for part 435 continues to read as follows:

    Authority: 33 U.S.C. 1311, 1314, 1316, 1317, 1318, 1342, and
1361.

0
17. Section 435.11 is amended as follows:
0
a. By revising paragraph (d).
0
b. By revising paragraph (e).
0
c. By revising paragraph (k)(2).

0
d. By revising paragraph (o).
0
e. By revising paragraph (t).
0
f. By revising paragraph (u).
0
g. By revising paragraph (v).
0
h. By revising paragraph (x).
0
i. By revising paragraph (ee).
0
j. By revising paragraph (gg).
0
k. By revising paragraph (hh).
0
l. By revising paragraph (ss).
0
m. By adding paragraph (uu).

Sec.  435.11  Special definitions.

* * * * *
    (d) Base fluid retained on cuttings as applied to BAT effluent
limitations and NSPS refers to the ``Determination of the Amount of
Non-Aqueous Drilling Fluid (NAF) Base Fluid from Drill Cuttings by a
Retort Chamber (Derived from API Recommended Practice 13B-2)'', EPA
Method 1674, which is published as an appendix to Subpart A of this
part and in ``Analytic Methods for the Oil and Gas Extraction Point
Source Category,'' EPA-821-R-11-004. See paragraph (uu) of this
section.
    (e) Biodegradation rate as applied to BAT effluent limitations and
NSPS for drilling fluids and drill cuttings refers to the ``Protocol
for the Determination of Degradation of Non Aqueous Base Fluids in a
Marine Closed Bottle Biodegradation Test System: Modified ISO
11734:1995,'' EPA Method 1647, supplemented with ``Procedure for Mixing
Base Fluids With Sediments,'' EPA Method 1646. Both EPA Method 1646 and
1647 are published as appendices to Subpart A of this part and in
``Analytic Methods for the Oil and Gas Extraction Point Source
Category,'' EPA-821-R-11-004. See paragraph (uu) of this section.
* * * * *
    (k) * * *
    (2) Dry drill cuttings means the residue remaining in the retort
vessel after completing the retort procedure specified in EPA Method
1674, which is published as an appendix to Subpart A of this part and
in ``Analytic Methods for the Oil and Gas Extraction Point Source
Category,'' EPA-821-R-11-004. See paragraph (uu) of this section.
* * * * *
    (o) Formation oil means the oil from a producing formation which is
detected in the drilling fluid, as determined by the GC/MS compliance
assurance method, EPA Method 1655, when the drilling fluid is analyzed
before being shipped offshore, and as determined by the RPE method, EPA
Method 1670, when the drilling fluid is analyzed at the offshore point
of discharge. The GC/MS compliance assurance method and the RPE method
approved for use with this part are published as appendices to Subpart
A of this part and in ``Analytic Methods for the Oil and Gas Extraction
Point Source Category,'' EPA-821-R-11-004. See paragraph (uu) of this
section. Detection of formation oil by the RPE method may be confirmed
by the GC/MS compliance assurance method, and the results of the GC/MS
compliance assurance method shall apply instead of those of the RPE
method.
* * * * *
    (t) Maximum weighted mass ratio averaged over all NAF well sections
for BAT effluent limitations and NSPS for base fluid retained on
cuttings means the weighted average base fluid retention for all NAF
well sections as determined by EPA Method 1674, which is published as
an appendix to Subpart A of this part and in ``Analytic Methods for the
Oil and Gas Extraction Point Source Category,'' EPA-821-R-11-004. See
paragraph (uu) of this section.
    (u) Method 1654A refers to EPA Method 1654, Revision A, entitled
``PAH Content of Oil by HPLC/UV,'' December 1992, which is published as
an appendix to Subpart A of this part and in ``Analytic Methods for the
Oil and Gas Extraction Point Source Category,'' EPA-821-R-11-004. See
paragraph (uu) of this section.
    (v) Minimum as applied to BAT effluent limitations and NSPS for
drilling fluids and drill cuttings means the minimum 96-hour
LC50 value allowed as measured in any single sample of the
discharged waste stream. Minimum as applied to BPT and BCT effluent
limitations and NSPS for sanitary wastes means the minimum
concentration value allowed as measured in any single sample of the
discharged waste stream.
* * * * *
    (x) No discharge of free oil means that waste streams may not be
discharged that contain free oil as evidenced by the monitoring method
specified for that particular stream, e.g., deck drainage or
miscellaneous discharges cannot be discharged when they would cause a
film or sheen upon or discoloration of the surface of the receiving
water; drilling fluids or cuttings may not be discharged when they fail
EPA Method 1617 (Static Sheen Test), which is published as an appendix
to Subpart A of this part and in ``Analytic Methods for the Oil and Gas
Extraction Point Source Category,'' EPA-821-R-11-004. See paragraph
(uu) of this section.
* * * * *
    (ee) Sediment toxicity as applied to BAT effluent limitations and
NSPS for drilling fluids and drill cuttings refers to EPA Method 1644:
``Method for Conducting a Sediment Toxicity Test with Leptocheirus
plumulosus and Non-Aqueous Drilling Fluids or Synthetic-Based Drilling
Muds'' and sediment preparation procedures specified in EPA Method
1646. EPA Method 1644 is published in ``Analytic Methods for the Oil
and Gas Extraction Point Source Category,'' (see paragraph (uu) of this
section) and EPA Method 1646 is published as an appendix to Subpart A
of this part.
* * * * *
    (gg) SPP toxicity as applied to BAT effluent limitations and NSPS
for drilling fluids and drill cuttings refers to the bioassay test
procedure, ``Suspended Particulate Phase (SPP) Toxicity Test,''
presented in EPA Method 1619, which is published as an appendix to
Subpart A of this part and in ``Analytic Methods for the Oil and Gas
Extraction Point Source Category,'' EPA-821-R-11-004. See paragraph
(uu) of this section.
    (hh) Static sheen test means the standard test procedure that has
been developed for this industrial subcategory for the purpose of
demonstrating compliance with the requirement of no discharge of free
oil. The methodology for performing the static sheen test is presented
in EPA Method 1617, which is published as an appendix to Subpart A of
this part and in ``Analytic Methods for the Oil and Gas Extraction
Point Source Category,'' EPA-821-R-11-004. See paragraph (uu) of this
section.
* * * * *
    (ss) C16-C18 internal olefin drilling fluid
means a C16-C18 internal olefin drilling fluid
formulated as specified in appendix 1 of subpart A of this part.
* * * * *
    (uu) Analytic Methods for the Oil and Gas Extraction Point Source
Category is the EPA document, ``Analytic Methods for the Oil and Gas
Point Source Category,'' December 2011, EPA-821-R-11-004, that compiles
analytic methods for this category. This incorporation by reference was
approved by the Director of the Federal Register in accordance with 5
U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected at the
National Archives and Records Administration (NARA). For information on
the availability of this material at NARA, call<PHONE_NUMBER>, or go to:
http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html. A copy may also be inspected at EPA's
Water Docket, 1200 Pennsylvania Ave. NW., Washington, DC 20460. This
method may be obtained

at http://water.epa.gov/scitech/methods/cwa/index.cfm.

0
18. In Sec.  435.12, Footnote 1 to the table is revised to read as
follows:

Sec.  435.12  Effluent limitations guidelines representing the degree
of effluent reduction attainable by the application of the best
practicable control technology currently available (BPT).

* * * * *
    \1\ No discharge of free oil. See Sec.  435.11(x).
* * * * *

0
19. In Sec.  435.13:
0
a. Remove ``LC5'' and add in its place ``LC50''
wherever it appears.
0
b. Footnotes 2, 3, and 5 through 11 to the table are revised to read as
follows:

Sec.  435.13  Effluent limitations guidelines representing the degree
of effluent reduction attainable by the application of the best
available technology economically achievable (BAT).

* * * * *
    \2\ As determined by the suspended particulate phase (SPP)
toxicity test. See Sec.  435.11(gg).
    \3\ As determined by the static sheen test. See Sec.
435.11(hh).
* * * * *
    \5\ PAH mass ratio = Mass (g) of PAH (as phenanthrene)/Mass (g)
of stock base fluid as determined by EPA Method 1654, Revision A,
[specified at Sec.  435.11(u)] entitled ``PAH Content of Oil by
HPLC/UV,'' December 1992, which is published as an appendix to
Subpart A of this part and in ``Analytic Methods for the Oil and Gas
Extraction Point Source Category,'' EPA-821-R-11-004. See Sec.
435.11(uu).
    \6\ Base fluid sediment toxicity ratio = 10-day LC50
of C16-C18 internal olefin/10-day
LC50 of stock base fluid as determined by EPA Method
1644: ``Method for Conducting a Sediment Toxicity Test with
Leptocheirus plumulosus and Non-Aqueous Drilling Fluids or
Synthetic-Based Drilling Muds'' after preparing the sediment
according to the procedure specified in EPA Method 1646, which are
published as appendices to Subpart A of this part and in ``Analytic
Methods for the Oil and Gas Extraction Point Source Category,'' EPA-
821-R-11-004. See Sec.  435.11(ee) and (uu).
    \7\ Biodegradation rate ratio = Cumulative headspace gas
production (ml) of C16-C18 internal olefin/
Cumulative headspace gas production (ml) of stock base fluid, both
at 275 days as determined by EPA Method 1647, which is published as
an appendix to Subpart A of this part and in ``Analytic Methods for
the Oil and Gas Extraction Point Source Category,'' EPA-821-R-11-
004. See Sec.  435.11(e) and (uu).
    \8\ Drilling fluid sediment toxicity ratio = 4-day
LC50 of C16-C18 internal olefin
drilling fluid/4-day LC50 of drilling fluid removed from
drill cuttings at the solids control equipment as determined by EPA
Method 1644: ``Method for Conducting a Sediment Toxicity Test with
Leptocheirus plumulosus and Non-Aqueous Drilling Fluids or
Synthetic-Based Drilling Muds'' after sediment preparation
procedures specified in EPA Method 1646, which are published as
appendices to Subpart A of this part and in ``Analytic Methods for
the Oil and Gas Extraction Point Source Category,'' EPA-821-R-11-
004. See Sec.  435.11(ee) and (uu).
    \9\ As determined before drilling fluids are shipped offshore by
the GC/MS compliance assurance method (EPA Method 1655), and as
determined prior to discharge by the RPE method (EPA Method 1670)
applied to drilling fluid removed from drill cuttings. If the
operator wishes to confirm the results of the RPE method (EPA Method
1670), the operator may use the GC/MS compliance assurance method
(EPA Method 1655). Results from the GC/MS compliance assurance
method (EPA Method 1655) shall supersede the results of the RPE
method (EPA Method 1670). EPA Method 1655 and 1670 are published as
appendices to Subpart A of this part and in ``Analytic Methods for
the Oil and Gas Extraction Point Source Category,'' EPA-821-R-11-
004. See Sec.  435.11(uu).
    \10\ Maximum permissible retention of non-aqueous drilling fluid
(NAF) base fluid on wet drill cuttings averaged over drilling
intervals using NAFs as determined by EPA Method 1674, which is
published as an appendix to Subpart A of this part and in ``Analytic
Methods for the Oil and Gas Extraction Point Source Category,'' EPA-
821-R-11-004. See Sec.  435.11(uu). This limitation is applicable
for NAF base fluids that meet the base fluid sediment toxicity ratio
(Footnote 6), biodegradation rate ratio (Footnote 7), PAH, mercury,
and cadmium stock limitations (C16-C18
internal olefin) defined above in this table.
    \11\ Maximum permissible retention of non-aqueous drilling fluid
(NAF) base fluid on wet drill cuttings average over drilling
intervals using NAFs as determined by EPA Method 1674, which is
published as an appendix to Subpart A of this part and in ``Analytic
Methods for the Oil and Gas Extraction Point Source Category,'' EPA-
821-R-11-004. See Sec.  435.11(uu). This limitation is applicable
for NAF base fluids that meet the ester base fluid sediment toxicity
ratio and ester biodegradation rate ratio stock limitations defined
as:
    (a) ester base fluid sediment toxicity ratio = 10-day
LC50 of C12-C14 ester or
C8 ester/10-day LC50 of stock base fluid as
determined by EPA Method 1644: ``Method for Conducting a Sediment
Toxicity Test with Leptocheirus plumulosus and Non-Aqueous Drilling
Fluids or Synthetic-Based Drilling Muds'' after sediment preparation
procedures specified in EPA Method 1646, which are published as
appendices to Subpart A of this part and in ``Analytic Methods for
the Oil and Gas Extraction Point Source Category,'' EPA-821-R-11-
004. See Sec.  435.11(ee) and (uu);
    (b) ester biodegradation rate ratio = Cumulative headspace gas
production (ml) of C12-C14 ester or
C8 ester/Cumulative headspace gas production (ml) of
stock base fluid, both at 275 days as determined by EPA Method 1647,
which is published as an appendix to Subpart A of this part and in
``Analytic Methods for the Oil and Gas Extraction Point Source
Category,'' EPA-821-R-11-004. See Sec.  435.11(e) and (uu); and
    (c) PAH mass ratio (Footnote 5), mercury, and cadmium stock
limitations (C16-C18 internal olefin) defined
above in this table.

0
20. In Sec.  435.14 footnote 2 to the table is revised to read as
follows:

Sec.  435.14  Effluent limitations guidelines representing the degree
of effluent reduction attainable by the application of the best
conventional pollutant control technology (BCT).

* * * * *
    \2\ As determined by the static sheen test. See Sec.
435.11(hh).
* * * * *

0
21. In Sec.  435.15:
0
a. Remove ``LC5'' and add in its place
``LC50''wherever it appears.
0
b. Footnotes 2, 3, and 5 through 11 to the table are revised to read as
follows:

Sec.  435.15  Standards of performance for new sources (NSPS).

* * * * *
    \2\ As determined by the suspended particulate phase (SPP)
toxicity test. See Sec.  435.11(gg).
    \3\ As determined by the static sheen test. See Sec.
435.11(hh).
* * * * *
    \5\ PAH mass ratio = Mass (g) of PAH (as phenanthrene)/Mass (g)
of stock base fluid as determined by EPA Method 1654, Revision A,
[specified at Sec.  435.11(u)] entitled ``PAH Content of Oil by
HPLC/UV,'' December 1992, which is published as an appendix to
Subpart A of this part and in ``Analytic Methods for the Oil and Gas
Extraction Point Source Category,'' EPA-821-R-11-004. See Sec.
435.11(uu).
    \6\ Base fluid sediment toxicity ratio = 10-day LC50
of C16-C18 internal olefin/10-day
LC50 of stock base fluid as determined by EPA Method
1644: ``Method for Conducting a Sediment Toxicity Test with
Leptocheirus plumulosus and Non-Aqueous Drilling Fluids or
Synthetic-Based Drilling Muds'' after preparing the sediment
according to the procedure specified in EPA Method 1646, which are
published as appendices to Subpart A of this part and in ``Analytic
Methods for the Oil and Gas Extraction Point Source Category,'' EPA-
821-R-11-004. See Sec.  435.11(ee) and (uu).
    \7\ Biodegradation rate ratio = Cumulative headspace gas
production (ml) of C16-C18 internal olefin/
Cumulative headspace gas production (ml) of stock base fluid, both
at 275 days as determined by EPA Method 1647, which is published as
an appendix to Subpart A of this part and in ``Analytic Methods for
the Oil and Gas Extraction Point Source Category,'' EPA-821-R-11-
004. See Sec.  435.11(e) and (uu).
    \8\ Drilling fluid sediment toxicity ratio = 4[dash]day
LC50 of C16-C18 internal olefin
drilling fluid/4-day LC50 of drilling fluid removed from
drill cuttings at the solids control equipment as determined by EPA
Method 1644: ``Method for Conducting a Sediment Toxicity Test with
Leptocheirus plumulosus and Non-Aqueous Drilling Fluids or
Synthetic-Based Drilling Muds'' after sediment preparation
procedures specified in

EPA Method 1646, which are published as appendices to Subpart A of
this part and in ``Analytic Methods for the Oil and Gas Extraction