Site-Specific Health and Safety Plan (HASP) - Laschools.org

SECTION 2
DATA QUALITY OBJECTIVES
The objectives of collecting and analyzing environmental samples are to determine the
distribution of chemicals of potential concern (COPCs) at the site. This QAPP has been
developed for use in conjunction with sampling activities to be undertaken at the site, and
describes the QA/QC procedures and protocols that will be used during sample analysis.
The QAPP will serve as a controlling mechanism during the investigation/remedial
action to ensure that a sufficient quantity of data is collected and that all data collected
are valid, reliable, and defensible. (Note: the evaluation of historical data for usability
will be addressed separately.)
An effective QA program addresses DQOs for both field sampling and laboratory
methods. The field QA efforts will focus on ensuring that samples are representative of
the conditions in the various environmental media at the time of sampling. Fixed-based
subcontract laboratory QA efforts will be aimed primarily at ensuring that analytical
procedures provide sufficient accuracy and precision to reliably quantify contaminant
levels in environmental samples. The subcontract laboratory will also ensure that
analyzed portions are representative of each sample.
DQOs are developed in general accordance with the seven-step DQO process presented
in USEPA (1994b) guidance for each field effort and included in the work plan for that
effort.
2.1 ANALYTICAL DATA QUALITY LEVELS
The analytical levels for this project’s DQOs will conform to the two USEPA-defined
categories of data. These data categories are defined below:
Screening Data - Screening data are generated by rapid, less precise methods of analysis
with less rigorous sample preparation. Sample preparation steps may be restricted to
simple procedures such as dilution with a solvent, instead of elaborate
extraction/digestion and cleanup. Screening data provide probable analyte identification
and approximate quantification.
Definitive Data - Definitive data are generated using rigorous analytical methods, such as
approved USEPA reference methods. Data are analyte-specific, with confirmation of
analyte identity and concentration. Methods produce tangible raw data (e.g.,
chromatograms, spectra) in the form of hard-copy printouts or computer-generated
electronic files. Data may be generated at the site or at an off site location, as long as the
QA/QC requirements are satisfied. For the data to be definitive, either analytical or total
measurement error must be determined. Results of fixed-based laboratory analyses of
samples collected at the site under this QAPP will be considered definitive data.
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