United States Office of SS'S±2*
Environmental Protection Solid Waste and EPA/540/R/94/083
Agency Emergency Response PB95-963525
December1994
Superfund
vxEPA LABORATORY DATA VALIDATION
FUNCTIONAL GUIDELINES FOR
EVALUATING INORGANICS
ANALYSES
REPRODUCED BY
U.S. DEPARTMENT OF COMMERCE
NATIONAL TECHNICAL
INFORMATION SERVICE
SPRINGFIELD, VA 22161
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9240.1-26
PB95-963525
EPA540/R-94/083
LABORATORY DATA VALIDATION
FUNCTIONAL GUIDELINES'FOR EVALUATING INORGANICS ANALYSES
t
Prepared for the
HAZARDOUS SITE EVALUATION DIVISION
U.S. ENVIRONMENTAL PROTECTION AGENCY
Compiled by
Ruth Bleyler
Sample Management Office
Viar St Company
Prepared by
The USEPA Data Review Work Group
Jeanne Hankins - EPA Region III - Chairperson
Frank Messina, Laura Scalise - EPA Region II
Gary Bennett - EPA Region IV
Ida Levin - EPA Region V
Mahmoud EI-Feky - EPA Region VI
Larry Marchin - EPA Region VII
July 1, 1988
U.S. Environmental Protection Agency
Region 5, Library (PL-12J)
77 West Jackson Boulevard, 12th Floor
Chicago, IL 60604-3590 //88
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TABLE OF CONTENTS
Page
INTRODUCTION 1
PRELIMINARY REVIEW 2
INORGANICS PROCEDURE 2
I. Holding Times 3
II. Calibration 4
HI. Blanks 6
IV. ICP Interference Check Sample (ICS) 7
V. Laboratory Control Sample (LCS) 9
^
v VI. Duplicate Sample Analysis 10
| VII. Matrix Spike Sample Analysis II
: VIII. Furnace Atomic Absorption QC 12
!
IX. ICP Serial Dilution 13
, X. Sample Result Verification 14
XI. Field Duplicates 14
XII. Overall Assessment of Data for a Case 15
GLOSSARY A: Data Qualifier Definitions 16
GLOSSARY B: Additional Terms 17
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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 general 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 7/87 Statement of Work (SOW) for Inorganics, Amendment 1
and December 1987 Revisions.
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 specify performance requirements on
matters that should be fully 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.
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 noj 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. (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 well as general laboratory
performance and any discernible 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 Contract Laboratory Program Quality Assurance
Coordinator (CLP QAC), the Regional Deputy Project Officer (DPO), and the Environmental
Monitoring Systems Laboratory in Las Vegas (EMSL/LV).
It is the responsibility of the data reviewer to notify the Regional DPO concerning
problems and shortcomings with regard to laboratory data. If there is an urgent requirement,
the DPO may be contacted by telephone to expedite corrective action. It is recommended
that all items for DPO 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.
Field 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
a) sample matrix
b) blanks*
c) field duplicates*
d) field spikes*
e) QC audit sample*
0 shipping dates
g) labs involved
* If applicable
The chain-of-custody 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 while assessing sample holding times.
INORGANICS PROCEDURE
The requirements to be checked in validation are listed below. ("CCS" indicates that
the contractual requirements for these items will 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)
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II. Calibration
o Initial (CCS)
o Initial and Continuing Calibration Verification (CCS)
III. Blanks (CCS)
IV. ICP Interference Check Sample (CCS)
V. Laboratory Control Sample (CCS)
VI. Duplicate Sample (CCS)
VII. Matrix Spike Sample (CCS)
VIII. Furnace Atomic Absorption QC (CCS)
IX. ICP Serial Dilution (CCS)
X. Sample Result Verification (CCS - 10%)
XL Field Duplicates
XII. Overall Assessment of Data for a Case
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 CFR 136 (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
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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.
Analyte Holding Time (Days) = Analysis Date - Sampling Date
D. Action
1. If 40 CFR 136 criteria for holding times and preservation are not met, qualify
all results > Instrument Detection Limit (IDL) as estimated (J) and results
< IDL as estimated (UJ).
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 sample results. The expected bias would be low and the reviewer may
determine that results < IDL are unusable (R).
3. Due to limited information concerning holding times for soil samples, it is left
to the discretion of the data reviewer whether to apply water holding time
criteria to soil samples. If the data are qualified when water holding time
criteria are applied to soil samples, it must be clearly documented in the
review.
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
Instruments must be calibrated daily and each time the instrument is set up.
a. ICP Analysis
A blank and at least one standard must be used in establishing the
analytical curve.
b. Atomic Absorption Analysis (AA)
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.
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2) The correlation coefficient must be >0.995.
Note: The correlation coefficient of 0.995 is a technical criterion
and not contractual.
c. Mercury Analysis
I) 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
I) 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 >0.995 is required for photometric
determination.
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-
I20%R.
c. Analysis results for cyanide must fall within the control limits of 85-
HS%R.
C. Evaluation Procedure
1. Verify that the instrument was calibrated daily and each time the instrument
was set up using the correct number of standards and blank.
2. Verify that the correlation coefficient is >0.995
3. Check the distillation log and verify that the midrange 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 . Found x 100
True
Where,
Found = concentration (in ug/L) of each analyte measured in the analysis of
the ICV or CCV solution
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True = concentration (in ug/L) of each analyte in the ICV or CCV source
D. Action
1. If the minimum number of standards as defined in section B were not used for
initial calibration, or if the instrument was not calibrated daily and each time
the instrument was set up, qualify the data as unusable (R).
2. If the correlation coefficient is <0.995, qualify results > IDL as estimated (J),
and results < IDL as estimated (UJ).
Note: For critical samples, further evaluation of the calibration curve may be
warranted to determine if qualification is necessary.
3. If the midrange CN standard was not distilled, qualify all associated results as
estimated (J).
4. If the ICV or CCV %R falls outside the acceptance windows, use professional
judgment to qualify all associated data. If possible, indicate the bias in the
review. The following guidelines are recommended:
a If the ICV or CCV %R falls outside the acceptance windows but within
the ranges of 75-89% or 111-125% (CN. 70-84% or 116-130%; Hg. 65-
79% or 121-135%). qualify results > IDL as estimated (J).
b. If the ICV or CCV %R is within the range of 111-125% (CN. 116-130%;
Hg, 121-135%). results < IDL are acceptable.
c. If the ICV or CCV %R is 75-89% (CN, 70-84%; Hg, 65-79%), qualify
results < IDL as estimated (UJ).
d. If the ICV or CCV %R is <75%, (CN, <70%; Hg. <65%), qualify all
positive results as unusable (R).
e. If the ICV or CCV %R is >125%, (CN >130%; Hg >135%). qualify results
> IDL as unusable (R); results < IDL are acceptable.
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 anv 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
Nc contaminants should be in the blank(s).
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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
Action in the case of unsuitable blank results depends on the circumstances and origin
of the blank. Sample results > IDL but <5 times the amount in any blank should be
qualified as (U).
Any blank with a negative result whose absolute value is > IDL must be carefully
evaluated to determine its effect on the sample data.
Note: The blank analyses may not involve the same weights, volumes, or dilution
factors as the associated samples. In particular, soil sample results reported on Form I
will not be on the same basis (units, dilution) as the calibration blank data reported on
Form HI. The reviewer may find it easier toovork f.^m the raw data when applying
5X criteria to soil sample data/calibration blank data.
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 not be corrected by
subtracting any blank value.
IV. ICP INTERFERENCE CHECK SAMPLE CICS)
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
1. 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 the laboratory reported values on Form IV.
ICS %R = Found Solution AB .««
True Solution AB
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Where,
Found Solution AB = concentration (in ug/L) of each analyte 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 analytes
which are not present in the ICS solution.
D. Action
I. 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
< IDL, this data is acceptable for use.
b. If the ICS recovery for an eleofent is >I20% and the sample results are
> IDL. qualify the affected data as estimated (J).
c. If the ICS recovery for an element falls between 50 and 79% and the
sample results are > IDL, qualify the affected data as estimated (J).
IDL are observed for elements which are not present in the EPA
provided 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 die ICS (false positives),
qualify sample results > IDL as estimated (J).
3. If negative results are observed for elements that are not present in the EPA
ICS solutions, and their absolute value is > IDL, 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 results
for the affected analytes < IDL as estimated (UJ).
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-22 of the 7/87 SOW.
These analyte concentration equivalents presented in the Table should be
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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 estimated (J).
V. LABORATORY CONTROL SAMPLE (LCS1
A. 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
1. All aqueous LCS results must fall within the control limits of 80-I20%R,
except Sb and Ag which have no control limits.
2. All solid LCS results must fall within the control limits established by the
EPA. This information is available from EMSL/LV.
C. Evaluation Procedure
1. Review Form VII and verify that results fall within the control limits.
2. Check the raw data (ICP printout, strip charts, bench sheets) to verify the
reported recoveries on Form VII. Recalculate one or more of the recoveries
(%R) using the following equation:
LCS %R - LCS Fpynd x I(X)
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
1. Aqueous LCS
a. If the LCS recovery for any analyte falls within the range of 50 - 79%
or >120%. qualify results > IDL as estimated (J).
b. If results are < IDL and the LCS recovery is greater than 120%, the
data are acceptable.
c. If results are < IDL and the LCS recovery falls within the range of 50-
79%, qualify the data for the affected analytes as estimated (UJ).
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d. If LCS recovery results are <50%, qualify the data for these samples as
unusable (R).
2. Solid LCS
a. If the solid LCS recovery for any analyte falls outside the EPA control
limits, qualify all sample results > IDL as estimated (J).
b. If the LCS results are higher than the control limits and the sample
results are < IDL, the data are acceptable.
c. If the LCS results are lower than the control limits, qualify all sample
results < IDL as estimated (UJ).
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 limit of ± 20% (35% for soil) for the Relative Percent Difference
(RPD) shall be used for sample values >5X CRDL.
3. A control limit of tCRDL (±2X CRDL for soil) shall be used for sample
values <5X CRDL, including the case when only one of the duplicate sample
values is <5X CRDL.
C. Evaluation Procedure
1. Review Form VI and verify that results fall within the control limits.
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.
RPD-
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
I. If duplicate analysts results for a particular analyte fall outside the appropriate
control windows, qualify the results for that ai.ulyte in all associated samples
of the same matrix as estimated (J).
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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.
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 field 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 results fall within the specified limits.
2. Check raw data and recalculate one or more %R using the following equation
to verify that results were correctly reported on Form V.
%R = (SSR-SR) x 100
SA
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 >I25% and the reported sample results are < IDL, the
data is acceptable for use.
2. If the spike recovery is >125% or <75% and the sample results are > IOL,
qualify the data for these samples as estimated (J).
3. If the spike recovery falls within the range of 30-74% and the sample results
are < IDL, qualify the data for these samples as estimated (UJ).
4.- If spike recovery results fall <30% and the sample results are < IDL, qualify
the data for these samples as unusable (R).
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5. If the field blank was used for matrix spike analysts, 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.
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.
VIII. FURNACE ATOMIC ABSORPTION PC
A. Objective
Duplicate injections and furnace post digestion spikes establish the precision and
accuracy of the individual analytical determinations.
B. Criteria
I. For sample concentrations > CRDL, duplicate injections must agree within
±20% Relative Standard Deviation (RSD), (or Coefficient of Variation (CV)),
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
7/87 SOW, p. E-15.
C. Evaluation Procedure
1. Check raw data to verify that duplicate injections agree within ±20% RSD (or
CV) 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 data as estimated (J).
2. If the rerun sample results do not agree within ±20% RSD (or CV), qualify the
data as estimated (J).
3. If the post digestion spike recovery is <40%, qualiiy results > IDL as estimated
(J).
4. If the post digestion spike recovery is >IO%, but <40%, qualify results < IDL
as estimated (UJ).
5. If the po*t digestion spike recovery is <10%, qualify results < IDL as unusable
(R).
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6. If sample absorbance h <50% of the post digestion spike absorbance then:
a. If the furnace pose digestion spike recovery is not within 85-115%,
qualify the sample results > 1DL as estimated (J).
b. If the furnace post digestion spike recovery is not within 85-115%,
qualify the sample results < IDL as estimated (UJ).
7. If Method of Standard Additions (MSA) is required but has not been done,
qualify the data as estimated (J).
8. If any of the samples run by MSA have not been spiked at the appropriate
levels, qualify the data as estimated (J).
9. If the MSA correlation coefficient is <0.995, qualify the data as estimated (J).
IX. ICP 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 IDL), an analysis of a 5-fold dilution must
agree within 10% Difference (%D) of the original results.
C. Evaluation Procedures
I. 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 IX.
%D . I!z3 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
diluted sample are significantly higher than the original sample.
D. Action
1. When criteria are not met, qualify the associated data 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 quantitation must be calculated according to the appropriate SOW.
C. Evaluation Procedures
The raw data should be examined to verify the correct calculation oT sample results
reported by the laboratory. Digestion and distillation logs, instrument printouts, strip
charts, etc. should be compared to the reported sample results.
1. Examine the raw data for any anomalies (i.e., baseline shifts, negative
absorbances, omissions, legibility, etc.).
2. Verify that there are no transcription or reduction errors (e.g., dilutions,
percent solids, sample weights) on one or more samples.
3. Verify that results fall within the linear range of the ICP (Form XIII) and
within the calibrated range for the non-ICP parameters.
4. Verify that sample results are >5X ICP IDL, if ICP analysis results are used
for As, TI. Se, or Pb.
("Jote: 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.
XI. 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 will have a greater variance than water
matrices due to difficulties associated with collecting identical field samples.
B. Criteria
There are no review criteria for field duplicate analyses comparability.
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C. Evaluation Procedures ,
Samples which are field duplicates should be identified using EPA Sample Traffic
Reports or sample field sheets. The 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.
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 limitation* 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 necessary 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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. GLOSSARY A
Data Qualifier Definitions
For the purposes of this document the following code letters and associated definitions are
provided.
U - The material was analyzed for. but was oot 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: Analyte may or may not be present.)
UJ - The material was analyzed for. but was oot detected. The associated value is
an estimate and may be inaccurate or imprecise.
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GLOSSARY 0
Additional Terms
Associated Samples
AA
Calibration Curve
Case
CCB
CCS
CCV
CLP
CRDL
CV
DPO
EMSL/LV
Field Blank
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 absorbance 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 deionized 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 with their findings.
Continuing Calibration Verification - a standard run
every ten samples designed to test instrument
performance. - •
Contract Laboratory Program
Contract Required Detection Limit
Coefficient of Variation
Deputy Project Officer
Environmental Monitoring System Laboratory/
Las Vegas (P.O. Box 15027, Las Vegas
Nevada 89114)
Field blanks are intended to identify contaminants
that may have been introduced in the field.
Examples are trip blanks, travel blanks,
rinsate blanks, and decontamination blanks.
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Field Duplicate
Holding Time
ICB
ICP
ICS
ICV
Initial Calibration
IRDA
LCS
MS
MSA
Post digestion Spike
QAC
RPD
RSCC
RSD
Serial Dilution
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
Interference Check Sample
Initial Calibration Verification - first 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 - introduction of a known concentration
of analyte into a sample to provide information about
the effect of the sample matrix on the digestion and
measurement 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 effects.
(ICP only)
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SDG Sample Delivery Group - defined by one of the
following, whichever occurs first:
case of field samples
each twenty field samples in a Case
each 14-day calendar period during which
field samples in a Case are received,
beginning with receipt of the first sample
in the SDG.
SMO Sample Management Office
SOP Standard Operating Procedure
SOW Statement of Work
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Region
INORGANIC REGIONAL DATA ASSESSMENT
CASE NO. SITE
LABORATORY NO. OF SAMPLES/
MATRIX
SDG* REVIEWER (IF NOT ESD)
SOW* REVIEWER'S NAME
DPO: ACTION FYI COMPLETION DATE
DATA ASSESSMENT SUMMARY
ICP AA Hg CYANIDE
1. HOLDING TIMES
2. CALIBRATIONS
3. BLANKS
1 . —*——^—. " ~~ - . . .
4. ICS
5. LCS
6. . DUPLICATE ANALYSIS
7. MATRIX SPIKE
8. MSA
9. SERIAL DILUTION
10. SAMPLE VERIFICATION
11. OTHER QC
12. OVERALL ASSESSMENT
O «= Data had oo problems/or qualified due to minor problems.
M = Data qualified due to major problems.
Z = Data unacceptable.
X - Problems, but do not affect data.
ACTION ITEMS:
AREAS OF CONCERN:
NOTABLE PERFORMANCE
U.S. Environmental Protection Agency
Region 5, Library (PL-12J)
77 West Jackson Boulevard, 12th Floor
I Kj>»j%^it.A. JJ ^,/iy A * -AA
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