4.1 Field QA demonstrates the effectiveness of field quality control procedures. Effective QA facilitates the collection of statistically significant data that is defendable scientifically and in a court of law. QA also involves the use of consistent procedures, increasing the validity of data comparison among sampling locations and events.

4.2 This guide should be used by a professional or technician who has training or experience in groundwater sampling.

Note 1: The quality of the results produced by this standard is dependent on the competence of personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.

1.1 This guide covers the quality assurance (QA) methods that may be used to assure the validity of data obtained during the sampling of a groundwater monitoring well. QA is any action taken to ensure that performance requirements are met by following standards and procedures. Following QA practices becomes even more critical if the data must be validated in a court of law. Under certain conditions, it may be necessary to follow additional or different QA practices from those listed in this guide. QA practices should be based upon data quality objectives, site-specific conditions, and regulatory requirements.

1.2 This standard addresses QA procedures used in the field and does not refer to laboratory QA procedures.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.4 This standard provides guidance for selecting and performing various field QA procedures. This document cannot replace education or experience and should be used in conjunction with professional judgement. Not all of the procedures are applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project’s many unique aspects. The word “standard” in the title of this document means only that the document has been approved through the ASTM consensus process.

1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.