Region III Modification
METALS
REGION III MODIFICATIONS
to the
LABORATORY DATA VALIDATION FUNCTIONAL GUIDELINES
for !
EVALUATING INORGANICS ANALYSES
April 1993
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TABLE OF CONTENTS
Page
INTRODUCTION .-. 1
PRELIMINARY REVIEW . 2
INORGANICS PROCEDURE .V.-. '. 3
I. . Holding Times f.mi .-.' 4
II. Calibration 5
III. Blanks 8
IV. ICP Interference Check Sample (ICS) 11
V. Laboratory Control Sample (LCS) 13
VI. Duplicate Sample , .. • 15
VII. Matrix Spike Sample Analysis ...- .... 16
VIII. Furnace Atomic Absorption QC . 18
DC. ICP Serial Dilution -. 20
• • / • • . • •
X Sample Result Verification . 21
XI. Field Duplicates 22
XII. Overall Assessment of Data for a Case 23
GLOSSARY A: DatavQualifier Definitions 24
GLOSSARY B: Additional Terms :... i 25
U. S. Environmental Protection Agency
Environmental Science Center
701MapesRoad
Ft. Meade, MD 20755-5350
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INTRODUCTION
This document is designed to offer guidance in laboratory data evaluation and validation. In some
aspects, it is equivalent to a Standard Operating Procedure (SOP). In other, more subjective areas, only genera]
guidance is offered due to the complexities and uniqueness of data relative to specific samples. These Guidelines
have been updated to include all requirements in the ILM03.0 Statement of Work (SOW) for Inorganics.
The review of laboratory data using these guidelines is considered equivalent to EPA Region Ill's "IM2"
level of review. "
Those areas where specific SOPs are possible are primarily areas in which definitive performance
requirements are established. These requirements are concerned with specifications that are not sample
dependent; they spedfy performance requirements on matters that should be rMTjr under a laboratory's control
These specific areas include blanks, calibration standards, calibration verification standards, laboratory control
standards, and interference check standards. In particular, mistakes such as calculation and transcription errors
must be rectified by resubmission of corrected data sheets by the laboratory.
This document is intended for technical review. Some areas of overlap between technical review and
Contract Compliance Screening (CCS) exist; however, determining contract compliance is not intended to be a
goal of these guidelines. It is assumed that the CCS is available and can be utilized to assist in the data review
procedure. • . '
' At times, there may be an urgent need to use data which do not meet all contract requirements and
technical criteria. Use of these data does not constitute either a new requirement standard or full acceptance
of the data. Any decision to utilize data for which performance criteria have not been met is strictly to facilitate
the progress of projects requiring the availability of the data. A contract laboratory submitting data which are
out of specification may be required to rerun or resubmit data even if the previously submitted data have been
utilized due to urgent program needs; data which do not meet specified requirements are never fully acceptable.
The only exception to this requirement is in the area of requirements for individual sample analysis; if the nature
of the sample itself limits the attainment of specifications, appropriate allowances must be made. The overriding
concern of the Agency is to obtain data which are technically valid and legally defensible.
All data reviews must have, as a cover sheet, the Inorganic Regional Data Assessment (IRDA) form
(CLP data only). (A copy is attached at the end of this document) If mandatory actions are required, they
should be specifically noted on this form. In addition, this form is to be used to summarize overall deficiencies
requiring attention, as weO as general laboratory performance and any discernable trends in the quality of the
data. (This form is not a replacement for the data review.) Sufficient supplementary documentation must
accompany the form to clearly identify the problems associated with a Case. The form and any attachments must
be submitted to the Regional Technical Project Officer CTPO).
It- is the responsibility of the data reviewer to notify the Regional TPO concerning problems and
shortcomings with regard to laboratory data. If there is an urgent requirement, the TPO may be contacted by
telephone to expedite,corrective action. It is recommended that all items for TPO action be presented at one
time. In any case, the Inorganic Regional Data Assessment form must be completed and submitted.
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PRELIMINARY REVIEW
»
In order to use this document effectively, the reviewer should have a general overview of the Case at
hand. The exact number of samples, their assigned numbers, their matrix, and the number of laboratories
involved in their analysis are essential information. Background information on the site is helpful but often this
information is very difficult to locate. The site project officer is the best source for answers or further direction.
CCS is a source of a large quantity of summarized information; It can be used to alert the reviewer of
problems in the Case or what may be sample-specific problems. This information may be utilized in data
validation. If CCS is unavailable, those criteria affecting data validity must be addressed by the data reviewer.
Cases routinely have unique samples which require special attention by the reviewer. Held blanks, field
duplicates, and performance audit samples need to be identified. The sampling records should provide:
1. Project Officer for site
2. Complete list of samples with notations on:
: r'*-~a) sample matrix . •
b) . blanks*
c) field duplicates*
d) field spikes*
e) QC audit sample*
f) shipping dates
g). labs involved
* If applicable . •
The chain-of.c\istody record includes sample descriptions and date of sampling. Although sampling date
is not addressed by contract requirements, the reviewer must take into account lag time between sampling and
shipping whili". a$$gss?ng sflmpfc. Tiqldlng trniftg
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INORGANICS PROCEDURE
%
The requirements to be checked in validation are listed below. ("CCS" indicates that the
contractual requirements for these items wfll also be checked by CCS; CCS requirements are not always the
same as the data review criteria.)
I. Holding Times (CCS - Lab holding times only)
II. Calibration ,
-InUial(CCS) ,
- TniHal anil Continuing Calibration Verification'(CCS)
m. Blanks (CCS)
f
IV. ICP Interference Check Sample (CCS)
V. Laboratory Control Samples (CCS)
VI. Duplicate Sample (CCS)
Vn. Matrix Spike Sample (CCS)
Vm. Furnace Atomic Absorption QC (CCS)
DC ICP Serial Dilution (CCS) .
X. Sample Result Verification (CCS -10%)
XI. Field Duplicates
XII. .' Overall Assessment of Data for a Case . .
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I. HOLDING TIMES
A. Objective
The objective is to ascertain the validity of results based on the holding time of the sample from time
of collection to time of analysis.
Note: The holding time is based on the date of collection, rather than verified time of sample receipt,
and date of digestion/distillation. It is a technical evaluation rather than a contractual requirement.
B. Criteria
>--
Technical requirements for sample holding times have only been established for water matrices. The
following holding time and preservation requirements were established under 40 CFR136 (Clean Water
Act) and are found in Volume 49, Number 209 of the Federal Register, page 43260, issued on October
26,1984.
METALS: 6 months; preserved to pH < 2 .
MERCURY: 28 days; preserved to pH < 2
CYANIDE: 14 days; preserved to pH > 12
C. Evaluation Procedure • . . -
Actual holding times are established by comparing the sampling date on the EPA Sample Traffic Report
with the dates of analysis found in the laboratory raw data (Digestion logs and instrument run logs).
Examine the digestion and/or distillation logs to determine if samples were preserved at the proper pH.
D. Action
1. If 40 CFR 136 criteria for holding times and/or preservation are not met, qualify all results
>JDL as biased low (L) and results L as biased low fUL). •
2. If holding times are exceeded, the reviewer must use professional judgment to determine the
. reliability of the data and the effects of additional storage on the same results. The expected
bias would be low and the reviewer may determine that results < DDL are unusable (R).
3. It is further required that metals and cyanide in properly preserved non-aqueous samples be
analyzed from the time of sample collection within the holding times as specified in 40CRF136
(see above). The narrative should state that due to the limited information concerning holding
times for soil samples, the water sample holding times were applied for soil samples.
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II. CALIBRATION
A. Objective
»
Compliance requirements for satisfactory instrument calibration are established to ensure that the
instrument is capable of producing acceptable quantitative data. Initial calibration demonstrates that
the instrument is capable of acceptable performance at the beginning of the analysis run, and continuing
calibration verification documents that the initial calibration is still valid.
\ •
B. Criteria
1. Initial Calibration
•*-v_ •
Instruments must be calibrated daily and each time the instrument is set up. :
a. ICP Analysis .
1) . A blank and at least one standard must be used in establishing the analytical
curve.
br~— Atomic Absorption Analysis (AA)
c-
1) A blank and at least three standards, one of which must be at the Contract
. Required Detection Limit (CRDL), must be used in establishing the analytical
curve.
2) The correlation coefficient must be > 0595.
Note: The correlation coefficient of 0595 is a technical criterion and not
contractual.
c. Mercury Analysis .
1) A blank and at least four standards must be used in establishing the analytical
curve. •••" .
•' 2) The correlation coefficient must be >0.995.
d. Cyanide Analysis
\ '• .
1) A blank and at least three standards must be used in establishing the
analytical curve.
2) . A midrange standard must be distilled.
3) . A correlation 'coefficient >Q.995 is required for photometric determination.
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Calibration
2. Initial and Continuing Calibration Verification (ICV and CCV)
a. Analysis results must fall within, the control limits of 90 - 110 percent Recovery (%R)
of the true value for all analytes except mercury and cyanide.
b. Analysis results for mercury must fall within the control limits of 80 - 120%R.
c. Analysis results for cyanide must fall within the control limits of 85 - 115%R.
C. Evaluation Procedure
1. Verify that the instrument was calibrated daily and eac\time the instrument was set up using
the correct number of standards and blank.
2. Verify that the correlation cooefficient is >0.995.
3. Check the distillation log and verify that the mid range CN standard was distilled.
4. Recalculate one or more of the ICV and CCV %R per type of analysis (ICP, GFAA, etc.)
using the following equation and verify that the recalculated value agrees with the laboratory
reported values on Form HA. Due to possible rounding discrepancies, allow results to fall
within 1% of the contract windows (e.g^ 89-111%).
%R = Pass* * 100
True'
Where,
Found = concentration (in ug/L) of each analyte measured in the analysis .of the ICV
or CCV solution
True = concentration (in ug/L) of each analyte in the ICV or CCV source
5. Check the CRQL (CRI and CRA) standard and verify % Recovery falls within 90-110%.
D. Action .
1. If the1 minimum nnmhr.r of standards as defined in section B were not used for initial
calibration, the reviewer should use professional judgement to qualify the data. However, if the
instrument was not calibrated daily and each time the instrument was set up, qualify the data
as unusable (R). In each case make note in the TPO section.
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Calibration
2. If the correlation cooeficient is < 0.995, qualify, results > DDL as'estimated (J), and results
IDL
L
K."
L "*
110
<75
CN
70-S4
. >U5
<70
Hg -"
65-79
>120
<65
5. If the CRDL standard %R falls outside the acceptance windows (± 10%), (except Hg and CN)
use the following guidelines to qualify the data: '
5a. If the CRDL recovery for an element is > 110% and the reported sample results are > IDL but
<2X CRDL qualify the affected data as biased high (KTl. .
5b. If the CRDL recovery for an element falls between 50% and 89%, quaHfy the affected data
>BDL but <2X CRDL as biased low (L\ and the affected data EDL but <2X CRDL
as biased extremely low (1A and the results
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III. BLANKS
A. Objective
The assessment of blank analysis results is to determine the existence and magnitude of contamination
problems. The criteria for evaluation of blanks applies to any blank associated with the samples. If
problems with .any. blank exist, all data associated with the Case must be carefully evaluated to determine
whether or not there is an inherent variability in the data for the Case, or if the problem is an isolated
occurrence not affecting other data.
B. Criteria
No contaminants should be in the blank(s).
C. ' Evaluation Procedures -
Review the results reported on the Blank Summary (Form III) as well as the raw data (ICP printouts,
strip charts, printer tapes, bench sheets, etc.) for all blanks and verify that the results were accurately
reported.:
D. Action
1. Results >IDL but .<5 times the amount in any blank should be qualified as(B).
2. If any blank has a negative result whose absolute value is >CRDL then all samples reported
below SX CRDLare qualified as biased low (L) and any non-detects (results
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Blanks
5. The following are examples of applying the blank qualification guidelines. Certain
circumstances may warrant deviations from these guidelines. Any deviations must be clearly
stated in the data review narrative. • ,
Example 1; Sample result is greater than the Instrument Detection Limit (IDL), but is less
than 5X the initial or continuing calibration (ICB or CCB) blank result.1
Aqueous:
Iron CCB Result: 50 ug/L
Iron IDL: 15ug/L
Iron Sample Result: 100 ug/L
Reported Sample Result: 100 B ug/L ^
Soik ;
• Iron CCB Result: " 50 ug/L (lOmg/Kg)
Iron IDL: 3 mg/Kg (15ug/L)
Iron Sample Result: 55 mg/Kg
Sample % Solids: 85%
5X CCB Result: 59 mg/Kg
-~s— Reported Sample Result: 55 B mg/Kg"
Please note that qualification of sample results due to ICB or CCB contamination affects only those samples analyzed
immediately after or before the ICB or CCB containing the contamination. If both CCBs bracketing samples are
contaminated, qualification should be based on the higher of the two CCB values.
Example 2: Sample result is greater than the Instrument Detection Limit (IDL) but is less
than 5X the equipment rinsate blank result2
Aqueous:
Sodnm Prep Blank Result: 22 ug/L
Sodium Equipment Blank Result2: 26 ug/L
Sodium CCB Result: 19 ug/L
Sodium IDL 15 ug/L
• . Sodium Sample Result 60 ug/L
Reported Sample Result2: 60 B ug/L
r • . -
.Soil:
Sodium Prep Blank Result: 8 mg/Kg
Sodium Equipment Blank Result2: 45 ug/L
* Sodium CCB Result: 30 ug/L
Sodium IDL: 15 ug/L
Sample Result : 52 mg/Kg (Dry weight)
Sample % Solids: 80.0%
5X Equipment Blank Result: 56 mg/Kg
Reported Sample Result2: 52 B mg/Kg
rlease note that qualification of the sample result a based oh the highest level of contamination found in the
associated blanks.
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Blanks
6. In instances where more than one blank is associated with a given sample, qualification should
be based upon a comparison with the associated blank having the highest concentration of a
contaminant The results must jujt be corrected by subtracting any blank value.
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IV. ICP INTERFERENCE CHECK SAMPLE (ICS)
A. Objective
The ICP Interference Check Sample verifies the contract laboratory's interelement and background
correction factors.
B. Criteria
1. An ICS must be run at the beginning and end of each sample analysis run (or a minimum of
twice per 8 hour working shift; whichever is more frequent).
2. Results for the ICS solution AB analysis must fall within the control limits of ± 20% of the true
value.
C. Evaluation Procedure
L - Recalculate from the raw data (ICP printout) one or more of the recoveries using the following
equation (%R) and verify that the recalculated value agrees with thelaboratory reported values
on Form IV.
Found Solution AB :
ICS %R = :—= X 100
True Solution AB .
Where, .
Found Sciatica AB = concentratioa (in ug/L) of each anaiyte measured in the analysis of
solution AB
True Solution AB - concentration (in ug/L) of each anaiyte in solution AB
2. • ' Check ICS raw data for results with an absolute value > IDL for those anarytes which are not
present in the ICS solution.
D. Action '
1. For samples with concentrations*of Al, Ca, Fe, and Mg which are comparable to or greater'
than their-respective levels in the Interference Check Sample: .
a. If the ICS recovery for an element is > 120% and the sample results are 120% and the reported sample results are
>IDL. qualify the affected data" as biased high (TO.
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ICP Interference Check Sample
c. If the ICS recovery for an element falls between 50 and 79% and the sample results
arc > IDL» qualify the data as biased low (L).
d. If the results are 1DL as
biased low (L). If the ICS recovery results for an element fall <50%. qualify results
EDL are observed for elements which are oof'present in the ICS solution, the
possibility of false positives exists. An evaluation of the associated sample data for the affected
elements should be made. For samples with comparable or higher levels of interferents and
with analyte concentrations that approximate those levels found in the ICS (false positives)
qualify sample results >IDL as biased high (TO.
3. if negative results are observed for elements that are not present in the EPA ICS solution, and
theirabsphite value is >E>L* the possibility of false negatives in the samples may exist If the
absolute value of the negative results is >IDL, an evaluation of the associated sample data
should be made. For samples with comparable or higher levels of interferents, qualify all
results H>L as biased
low(L).
4. In general, the sample data can be accepted if the concentrations of Al, Ca, Fe and Mg in the
sample are found to be less than or equal to their respective concentrations in the ICS. If these
elements are present at concentrations greater than the level in the ICS, or other elements are
present in the sample at >10 mg/L, the reviewer should investigate the possibility of other
interference effects by using Table 2 given on page D-26 of the ELM03.0 SOW. These analyte
concentration equivalents presented in the Table should be considered only as estimated values,
since the exact value of any analytical system is instrument specific. Therefore, estimate the
concentration produced by an interfering element. If the estimate is >2X CRDL and also
greater than 10% of the reported concentration of the affected element, qualify the affected
results as biased high 00. 7
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V. LABORATORY CONTROL SAMPLE rLCS)
Objective
The laboratory control sample serves as a monitor of the overall performance of all steps in the analysis,
including the sample preparation.
B. Criteria
**•*..
L AD- aqueous LCS recoveries must fall within the control limits of 80-120%, except Ag and Sb
which have no control Emits.
2. All solid LCS results must fall within the control limits established by the EPA. This
information b available from EMSL/LV. '
C. Evaluation Procedure
1. Review Form VQ and verify that results fall within the control Emits.
2. Check the raw data (TCP printout, strip charts, beach sheets) to verify the reported recoveries
on Form VH. Recalculate one or more of the recoveries (%R) using the following equation:
LCS Found
LCS %R = — — X 100
LCS True
Where,
LCS Found = Concentration (in ug/L for aqueous, mg/kg for solid) of each analyte
measured in the analysis of LCS solution
LCS True = Concentration (in ug/L for aqueous, mg/kg for solid) of each analyte in the
LCS source
D. Action
* . ~ •
V .
1. Aqueous LCS
a. If the LCS recovery for any analyte falls within the range of 50-79%, qualify results
>IDL as biased low (L). If the LCS recovery is > 120% qualify results >IDL as
biased high flO.
b. If results are
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Laboratory Control Sample (LCS)
c. If results are BDL as biased" tow (L). If the solid LCS recovery
is greater than the upper limit of the EPA control limit, qualify all results '>IDL as
biased high flO.
b. If the LCS results are higher than the control limits and the sample results are < IDL,
the data are acceptable.
c ~ ~- If the solid LCS results are lower than the control limits, qualify all results
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VI. DUPLICATE SAMPLE ANALYSIS
A. Objective
Duplicate analyses are indicators of laboratory precision based on each sample matrix.
B. Criteria
1. Samples identified as field blanks cannot be used for duplicate sample analysis.
2. A control Emit of ± 20% (35% for soil) for the Relative Percent Difference'(RPD) shall be
used for duplicate sample values >5X CRDL. .
3. A control limit of ± CRDL (± 2X CRDL for soil) shall be used for duplicate sample values
<5X CRDL, including the case when only one of the duplicate sample values is <5X CRDL.
C. EvaluaUoif Procedure
1. Review Form VI and verify that results fall within the control Emits.
2. Check the raw data and recalculate one or more RPD using the following equation to verify
that results have been correctly reported on Form VI.
Where, .
S - First Sample Value (original)
D = Second Sample Value (duplicate)
3. Verify that the field blank was not used for duplicate analysis. '
D. Action
1. If duplicate analysis results for a particular analyte fall outside the appropriate control windows,
qualify the .results for that analyte in all associated samples of the same matrix as estimated (J).
2. If the field blank was used for duplicate analysis, all other QC data must be carefully checked
and professional judgment exercised when evaluating the data.
Note: This information must be included on the IRDA form.
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.VII. MATRIX SPIKE SAMPLE ANALYSIS
A. Objective .
The matrix spike sample analysis provides information about the effect of each sample matrix on the
digestion and measurement methodology. .
B. Criteria
1. Samples identified as Geld blanks cannot be used for spiked sample analysis.
2. Spike recovery (%R) must be within the limits of 75-125%. However, spike recovery limits do
not apply when sample concentration exceeds the spike concentration by a factor of 4 or more.
C. Evaluation Procedure
1. Review Form V and verify that the results fall within the specified limits.
^-^.^
Z Check raw data and recalculate one or more %R using the following equation to verify that
results were correctly reported on Form V.
%R = ISSKOK) ^ m
Where,
SSR = Spiked Sample Result
SR = Sample Result
SA = Spike Added
3. Verify that the field blank was not used for spike analysis.
D. Action .
1. If-the spike recovery is >125% and the reported sample results are 125% and the results are >IDL, qualify the data as biased high (K).
If the jecoverv is <75%. qualify the results >IDL as biased low (L).
3. If the spike recovery falls within the range of 30-74% and the sample results are < IDL, qualify
the data as biased low fUL).
4. If spike recovery results fall <30% and the sample results are IDL, qualify the data as biased extremely low
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Matrix Spike Sample
5. If the Geld blank was used for matrix .spike analysis, aO other QC data must be carefully
checked and professional judgment exercised when evaluating the data. .
Note: This information must be included on the IRDA form.
Note: If the matrix spike recovery does not meet criteria (except in Ag), a post digestion spike is
required for all methods except furnace, but this data is not used to qualify sample results. However,
this information must be included in the IRDA report. For flame AA, IGP and CN analyses, when the
pre-digestion/pre-distiilation spike recovery fails outside the control limits and the sample result does
not exceed 4X the spike added, a post-digestion/post-distgiation'qpke most be performed for those
elements that do not meet the specified criteria (exception: Ag). The nnspiked aliquot" of the sample
should be spiked at 2X the indigenous level or 2X CRDL, whichever is greater. If post-digestion/post-
distillation spike %R falls outside the control limits make a note in the IPO section.
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VIII. FURNACE ATOMIC ABSORPTION PC
A. Objective
Duplicate injection and furnace post digestion spikes establish the precision and accuracy of the
individual analytical determinations.
B. Criteria
1. For sample concentrations >CRDL, duplicate injections must agree within ± 20% Relative
Standard Deviation (RSD), (or Coefficient of Variation (OV)), otherwise the sample must be
' • rerun once (at least two additional injections).
2. Spike recovery must be >85% and <115%.
3. The Furnace Atomic Absorption Scheme must be followed as described in the BLM03.0 SOW.
C. Evaluation Procedure
1. Check raw data to verify that duplicate injections agree within ± 20% RSD (or CY) for sample
concentrations > CRDL.
2. Review Furnace AA raw data to verify that the Furnace Atomic Absorption Scheme has been
followed. •
D. Action
1. If duplicate injections are outside the ± 20% RSD (or CV) limits and the sample has not been
rerun once as required, qualify the results >IDL as estimated (J) and results IDL
as estimated (J) and results IDL as biased low (L).
4. If the analytical/post digestion spifce recovery is >10% but <40%, qualify results IDL as
biased low (LI and results
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Furnace Atomic Absorption QC .
6. When sample absorbance is <50% of (be post digestion spike absorbance then:
a. If the furnace analytical/post digestion spike recovery is <85%, qualify results > IDL
as biased low (L). If the recovery is >115%. qualify the results >IDL as biased
high OO.
b. If the furnace analytical/post digestion spike recovery is <85%, qualify the results
IDL as estimated (J), and results < DDL estimated (UJ).~
8. If any of the samples run by MSA have not "been spiked at the appropriate levels, qualify results
>IDL as estimated (J) and results DDL as estimated (J) and results
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IX. 1CP SERIAL DILUTION
A. Objective
The serial dilution determines whether significant physical or chemical interferences exist due to sample
matrix
B. Criteria
If the analyte concentration is sufficiently high (concentration in the*original sample is minimally a factor
of 50 above the H>L), an analysis of a 5-fold dilution must agree within 10% Difference (%D) of the
original results. .
C. Evaluation Procedures
1. Check the raw data and recalculate the %D using the following equation to verify that the
dilution analysis results agree with results reported on Form DC
%D = •"="« x 100
Where,
I = Initial Sample Result
S = Serial Dilution Result (Instrument Reading x 5)
2. Check the raw data for evidence of negative interference, i.e., results of the dilution sample are
significantly higher than the original sample.
D. - Action
1. When criteria are not met, qualify the results as estimated (J).
2. . If* evidence of negative interference is found, use professional judgment to qualify the data.
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X. SAMPLE RESULT VERIFICATION
A. Objective
The objective is to ensure that the reported quantitation results are accurate.
B. Criteria
Analyte quantitaticn must be calculated according to the appropriate SOW.
C. Evaluation Procedures
The raw data should be examined to verify the correct calculation of sample results reported by the
laboratory. Digestion and distillation logs, instrument printouts, strip charts, eta, should be compared
to the reported sample results. •
L Etamine the raw data for any anomalies (Le, baseline shifts, negative absorbances, omissions,
legibility, etc).
2. Verify that there are no transcription or reduction errors (e.&, dilutions, percent solids, sample
weights) on one or more samples. • " • '•
3. Verify that results fall within the linear range of the ICP (Form XHT) and within the calibrated
range for the non-ICP parameters.
4. Verify that sample results are >5X ICP 1DL» if ICP analysis results are used for As, TJ, Se, or
Pb. '
s
Note: When the laboratory provides both ICP and furnace results for an analyte in a sample and the
concentration is >ICP IDL, the results can assist in identifying quantitation problems.
D. Action
If there' are any discrepancies found, the laboratory may be contacted by the designated representative
to obtain additional information that could resolve any differences. If a discrepancy remains
unresolved, the reviewer may determine qualification of the data is warranted.
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XL FIELD DUPLICATES
A. Objective
Field duplicate samples may be taken and analyzed as an indication of overall precision. These analyses
measure both field and lab precision; therefore, the results may have more variability than lab duplicates
which measure only lab performance. It is also expected that soil duplicate results wiHhave a greater
variance than water matrices due to difficulties associated with collecting identical field1 samples.
B. Criteria . ""' '
There are no review criteria for field duplicate analyses comparability.
C. Evaluation Procedures
p
Samples which are field duplicates should be identified using EPA Sample Traffic Reports or sample
field sheets. "fEe" reviewer should compare the results reported for each sample and calculate the
Relative Percent Difference (RPD), if appropriate.
D. Action .
Any evaluation of the field duplicates should be provided with the reviewer's comments.
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XII. OVERALL ASSESSMENT OF DATA FOR A CASE
It is appropriate for the data reviewer to make professional judgments and express concerns and
comments on the validity of the overall data for a Case. This is particularly appropriate when there are several
QC criteria out of specification. The additive nature of QC factors out of specification is difficult to assess in
an objective manner, but the reviewer has a responsibility to inform the user concerning data quality and data
limitations in order to assist that user in avoiding inappropriate use .of the data, while not precluding any
consideration of the data at all If qualifiers other than those used in this document are necessary to describe
or qualify the data, it Is accessary to .thoroughly document/explain the additional qualifiers used. The data
reviewer would be greatly assisted in this endeavor if the data quality objectives were provided. The cover form
and supplementary documentation must be included with the review. .
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Region III Modifications
METALS
GLOSSARY A
»
Data Qualifier Definitions
For the purposes of this document,the following code letters and associated definitions are provided.
U - The analyte was analyzed for, but was not detected above the level of the
associated value. The associated value is either the sample quantitation limit
or the sample detection limit. -•*-
J - The associated value is an.estimated quantity.
R - The data are unusable. (Note: The analyte may or may not be present.)
UJ - The analyte was analyzed for, but was not detected. The associated detection
;• ---^ Emit is an estimate and may be inaccurate or imprecise.
K - The analyte is present. The reported value may be biased high. The actual
value is expected to be lower than reported.
L - The analyte is present. The reported valves may be biased low. The actual
value is expected to be higher than reported.
UL - The analyte was not detected, and the reported quantitation limit is probably
higher than reported.
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Region III Modification
METALS
Associated Samples
AA
Calibration Curve
Case
CCB
CCS
CCV
CLP
CRDL
CV
EMSL/LV
Field Blank
*
Field Duplicate
Holding Time
ICB
ICP
GLOSSARYB
Additional Terms • ' . • .
Any sample related to a particular QC analysis.
For example: *
- For ICV, all samples run under the same calibration curve.
- For duplicate RPD, all SDG samples digested/distilled of the same
matrix. .
Atomic Absorption
A plot of absprbance versus concentration of standards.
A finite, usually predetermined number of samples collected in a
given time period for a particular site. A Case consists of one'or
more Sample Delivery Groups. •
Continuing Calibration Blank - a HiAmw.^ water sample run every
ten samples designed to detect any carryover contamination.
Contract Compliance Screening - process in which SMO inspects
analytical data for contractual compliance and provides EMSL/LV,
laboratories and> the Regions \nth their findings.
Contmuing Calibradon Verification.- a standard run. every ten
samples designed to test instrument performance.
Contract Laboratory Program , .
Contract Required Detection Limit
Coefficient of Variation '
Environmental Monitoring System Laboratory/Las Vegas (P.O. Box
15027, LasVegas, Nevada 89114) '/:
Field blanks 'are intended to identify cff"t}>T"'iants that may have
been introduced in the field. Examples are travel, blanks, rinsate
blanks, and decontamination blanks...
»''.-••• • "•. • ': '
A duplicate sample generated in the field; not in the laboratory.
The time from sample collection to laboratory analysis.
Initial Calibration Blank -first blank standard run to confirm the
calibration curve.
Inductively Coupled Plasma'
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Region III Modifications
METALS
Glossary B
ICS
1CV
Initial Calibration
IRDA
LCS
MS *
MSA
Post digestion Spike
QAC .
RSCC .
RSD
Serial Dilution
SDG
SMO
SOP
SOW
Interference Check Sample '
Initial Calibration Verification - fust standard run to confirm the
calibration curve.
The establishment of a calibration curve with the appropriate number
of standards and concentration range. The calibration curve plots
absorbance or emission versus concentration of standards.
Inorganic Regional Data Assessment
Laboratory Control Sample - supplied by EPA
Matrix Spike r: introduction'of a known concentration of anaiyte into
a sample to provide information about the effect of the sample matrix
on the.digestion and;measureinent methodology.
Method of Standard Addition -
The addition of a known amount of standard after digestion. (Also
identified as analytical spike, or spike, for furnace .analyses.)
Quality Assurance: Coordinator '
Relative Percent Difference
Regional Sample Control Center
Relative Standard Deviation
A sample run at a specific dilution to- determine whether any
significant chemical; or .physical interferences-exist due to sample
matrix elects. (ICP onty) •,'""•"
Sample. Delivery Group - defined by one of the following, whichever
occurs first .... f , , . ' :
- case of field samples
- each twenty field samples in a Case
• Each 14-day calendar period during which field samples in a Case
are recerved,rjeg?nning with receipt of the first sample in the SDG.
Sample Management Office
Standard Operating Procedure
Statement of Work
26
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