Application of PARCC Parameters.

ETL 1110-1-158

28 Feb 95

Strict adherence to standard operating procedures during sampling

and analysis, and avoiding field cross-contamination by

implementation of thorough decontamination procedures will ensure

a high degree of accuracy.

(c) Representativeness is the degree to which data

accurately and precisely portrays the environmental conditions

being studied.

(d) Comparability is the qualitative estimate of the

relative confidence with which the data obtained from one set of

measurements may be compared to data from another set of

measurements. The degree of comparability is directly related to

the precision, accuracy, and representativeness of the data in

each set. Factors that are likely to contribute to systematic

and random error of the data should be evaluated and appropriate

methods that allow collection of the type, quality, and quantity

of data needed for the treatability study should be selected.

(e) Completeness is the estimate of the number of valid

measurements made as compared to the total number of measurements

performed. The level of completeness required for a given set of

data is determined by the number of valid measurements that must

be obtained to satisfy the data use. To emphasize, comparability

and representativeness are qualitative objectives of the data;

while completeness goals are defined for individual sampling and

analytical protocols or may be combined to assess the project as

a whole. Precision and accuracy parameters, on the other hand,

represent quantitative limits below which data is unacceptable,

and corrective action must be taken.

(5) Application of PARCC Parameters. Precision and accuracy

goals may be established at levels specified within the methods

or more stringent as required by project DQOs. If no goals are

presented within the methods, project specific ranges must be

established for precision and accuracy in order to generate data

of consistent quality throughout the study.

(6) QA/QC Procedures. Quality assurance/quality control

procedures are a program of field and laboratory operations

employed to assess the validity of the sampling and analytical

work performed. Sampling QA/QC procedures normally require the

acquisition of replicate samples (field duplicates, splits, etc.)

and associated blanks (rinsates, trip blanks, etc.). Laboratory

QA/QC procedures encompass the required analysis of method

blanks, duplicate samples, surrogate compounds, spike samples,

etc. These operations allow calculation of both field and

laboratory precision and accuracy achieved in conjunction with

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