Quality Assurance and Quality Assurance Project Plans
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Quality Assurance/Quality Control
and
Quality Assurance Project Plans
Greg Thoma
University of Arkansas
IPEC Quality Assurance Officer
Quality Assurance/Quality Control
QA is management of the data collection system
to assure validity of the data.
Organization & responsibilities
QC refers to technical activities which provide
quantitative data quality information.
Data quality indicators, Calibration procedures.
Quality Assurance Project Plan
Document that provides the details of QA & QC for a
particular project
Quality?
How good is “good enough”? 99.9% of the time?
1 hour unsafe drinking water a month
22,000 checks deducted from the wrong account an hour
16,000 pieces of lost mail an hour
What does data quality mean?
Universal standard? Relative measure?
The goal of generators of environmental data should
be to produce data of known quality to support
environmental decisions
Is the site clean?
Does the technology work?
Scientific Method
Invent a tentative theory or
Observe something
hypothesis consistent with
interesting
the observations
Test the predictions with Use the hypothesis
planned experiments to make predictions
Discrepancies How do you know if
between there are discrepancies?
observation
and Uncertainty in observed
theory? valued reduces the ability to
discriminate differences.
No
Modify the hypothesis in Yes Conclude the
light of the results theory is true
Data Life Cycle
Performance and Acceptance Criteria
Performance criteria address the
adequacy of information that is to be
collected for the project.
“Primary” data.
Acceptance criteria address the
adequacy of existing information
proposed for inclusion in the project.
“Secondary” (literature) data.
Performance and Acceptance Criteria
Effective data collection is rarely achieved in a
haphazard fashion.
The hallmark of all good projects, studies, and
decisions is a planned data collection.
A systematic process leads to the development of
acceptance or performance criteria that are:
based on the ultimate use of the data to be collected,
and
define the quality of data required to meet the final
project objectives.
QAG/4A
Performance and Acceptance Criteria
The PAC development process helps to
focus studies by encouraging experimenters
to clarify vague objectives and explicitly
frame their study questions.
The development of PAC is a planning tool
that can save resources by making data
collection operations more resource-
effective.
PAC Process at Project Level
State the problem
Oil contaminated soil needs to be remediated
Identify the study questions
Testable hypotheses rather than general objectives
• We hypothesize that the contaminated soil, under nutrient rich
conditions, will exhibit the highest rates of degradation due to
the history of hydrocarbon exposure these microbial
communities have experienced.
Establish study design constraints
Budget, timeline, spatial extent, technical issues, etc.
• 7 factors, 2 levels, 4 reps, 8 sample times!!!!
PAC Process at Project Level
Identify data requirements
What needs to be measured?
Soil properties, nutrient status, contaminant level, etc.
Specify information quality
May be qualitative
• Representativeness, comparability
or quantitative
• DQI: precision, bias, accuracy, and sensitivity
Strategy for information synthesis
How will it be analyzed? AVOVA? Regression?
Optimize experimental design
Get „good enough‟ data at the lowest cost
QA in Your Future?
Intergovernmental Data Quality Task Force:
Uniform Federal Policy for Implementing
Environmental Quality Systems
Joint initiative between the EPA, DoD, and DOE to
resolve data quality inconsistencies and/or deficiencies
to ensure that:
• Environmental data are of known and documented quality and
suitable for their intended uses, and
• Environmental data collection and technology programs meet
stated requirements.
And don‟t forget TQM, ISO9000, & Six Sigma!
A Graded Approach
The level of planning detail and documentation may:
correspond to the importance of the project to its
stakeholders
• e.g. significant health risks associated.
reflect the overall scope and budget of the effort
• Superfund cleanup vs. proof-of-concept research
be driven by the inherent technical complexity or the
political profile of the project
• complex or politically sensitive projects generally require more
documentation.
Quality Assurance Project Plan
Documentation of routine laboratory
practice
Elements
A. Project Management
B. Data Generation and Acquisition
C. Assessment and Oversight
D. Data Validation and Verification
Group A.
Project Management
Title Page
Signature Approval Sheet
Table of Contents
Distribution List
Project/Task Organization
Problem Definition/Background
Project/Task Description and Schedule
Quality Objectives (linked to PAC)
Special Training Requirements/Certification
Documentation and Records
Performance Criteria for
Phytoremediation Project
Critical Complete- MDL
Method Reference Precision Bias
measurement ness
EPA 3540c 70-
TPH (in soil) GC/FID 25% 90% 10 mg/kg
EPA 8015 130%
PAH and GC/MS- 70-
EPA 8270 25% 90% 150 mcg/kg
Biomarker SIM 130%
Oil-Degrader
Haines et 0.3 log
Numbers (in MPN NA 90% 2 MPN/g
al., (1996) units
soil)
Plant Biomass Salisbury
Gravi-
Shoots and Ross NA NA 90% 0.1 g
metric
Roots (1985)
Performance Criteria for
Phytoremediation Project
Non- Critical Complete- MDL
Method Reference Precision Bias
measurement ness
Microbial
PLFA by Kennedy
community N/A N/A 90% N/A
GC/MS (1994)
structure
Plant available
Ca, Mg, Cu, Zn Mehlich Donohue 90-
20% 90% 1 mg/kg
and Na 3 ICP (1992) 110%
(in soil)
Rhoades
Salinity Salinity 10% N/A 90% 1 dS/m
(1996)
Acceptance criteria will be developed for published meteorological data and data
generated in other studies used in the modeling for this project.
Data Quality Indicators
Bias: systematic factor causing error in one
direction
Precision: agreement of repeated measures of the
same quantity
Accuracy: combination of precision and bias
Representativeness: how well the sample
represents the population
Comparability: how well two or more datasets
may be combined
Completeness: measure of the amount of valid
data to the total planned collection of data.
Sensitivity: separating the signal from the noise
Accuracy
Components of Variability
Representativeness
Extremely important
NAAQS sampling next to a bus stop??
Stack gas monitoring – isokinetic sampling
Sampling plan design
Number and locations
Size and sampling method and handling
• Grab vs. composite, preservation methods, etc.
Group B.
Measurement/Data Acquisition
Experimental Design
Sampling Methods Requirements
Sample Handling and Custody Requirements
Analytical Methods Requirements
Quality Control Requirements
Instrument/Equipment Testing, Inspection, and
Maintenance Requirements
Instrument Calibration and Frequency
Inspection/Acceptance Requirements for Supplies
Data Acquisition Requirements (Non-direct Measurements)
Data Management
Sample Handling and Preservation
Quality Control Checks
Impact of Detection Limit and
Contaminant Concentration on Reporting
MDL and False Positive Errors
For 7 injections,
t = 3.71
MDL and False Negative Errors
Group C.
Assessment and Oversight
Assessments and Response Actions
Procedures for monitoring data quality as it is
collected
Actions to be taken in the event of failure to
meet performance criteria
• Stop analysis, correct problem, reanalyze
Reports to Management
Group D.
Data Validation and Usability
Data review, verification, and validation
Review
• Check for transcription or data reduction errors and
completeness of QC information.
Verification
• Were the procedures in the QAPP accurately followed?
Validation
• Does the data meet the PAC specified in the QAPP?
Reconciliation with user requirements
Is the data suitable for use by decision makers?
Data Quality Assessment (DQA):
The DQA process is a quantitative process
Based on statistical methods
Does set of data support a particular decision with an acceptable
level of confidence?
5 Steps:
Review the PAC and sampling design;
Conduct a preliminary data review;
Select the statistical test;
Verify the assumptions of the statistical test; and
Draw conclusions from the data.
Example Quality Control Charts
RPD =
%R =
Surrogate Recovery Example
Decane recovery (%)
QC batch number
A.Apblett , “Novel materials for facile separation of petroleum products from aqueous
mixtures via magnetic filtration”
Benefits of Up-front Systematic
Planning
Focused data requirements and optimized
design for data collection;
Use of clearly developed work plans for
collecting data in the field;
A well documented basis for data
collection, evaluation, and use;
Clearer statistical analysis of the final data;
Sound, comprehensive QA Project Plans.
Benefits of QA
Clear lines of responsibility
Documented training and analytical
competence
Standard procedures to assure data
comparability
Catch and correct subtle mistakes/errors
Conclusions
Why go through the hassle & headache?
QA/QC is just good science.
Documented, defensible data.
It is cheaper to do it right the first time.
Your next proposal will be better too!
Website
Virtually all roads lead to:
www.epa.gov/quality
Data Acquisition
Experimental Design
Will the results allow assessment of the
hypothesis?
Sampling Methods
Is it representative?
How is it preserved? Transported?
Cross contamination
Data Acquisition (cont)
Analytical Measurement Methods
Quality Control
Calibration
Bias & Precision
• Blanks, Duplicates, Spikes
Instrument Control
Project Management
Organization & Responsibilities
Quality Objectives & Criteria
What do you want to know? (Hypothesis)
What are you measuring and how „good‟ the
data needs to be.
Record Keeping
Lab, Field, Instrument notebooks
QA Plan for Development of Models
Project Description
Model Description - Conceptual Model
Computational Aspects
Data Source/Quality/Input-Output
Model Validation
Model Application
Common Mistakes in MDL
Determination
Miscalculation
Incorrect standard deviation
Incorrect degrees of freedom
Insufficient replicates (need 7)
Spike out of range
Lowest standard too far from MDL
Using method based MDL w/o verification
of validity for current matrix
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