Standard Practice for Direct Push Installation of Prepacked Screen Monitoring Wells in Unconsolidated Aquifers

Importancia y uso:

5.1 This practice is intended to provide the user with information on the appropriate methods and procedures for installing prepacked screen monitoring wells by direct push methods. The monitoring wells may be used to obtain representative water quality samples for aqueous phase contaminants or other analytes of interest, either organic or inorganic (3, 6-8). The monitoring wells may also be used to obtain information on the potentiometric surface of the local aquifer and properties of the formation such as hydraulic conductivity or transmissivity.

5.2 Use of direct push methods to install monitoring wells can significantly reduce the amount of potentially hazardous drill cuttings generated during well installation at contaminated sites. This may significantly reduce cost of an environmental site investigation and groundwater monitoring program. Minimizing generation of hazardous waste also reduces the exposure hazards to site workers, local residents, and the environment.

5.3 Direct push methods for monitoring well installation are limited to use in unconsolidated formations such as alluvial/stream sediments, glacial deposits, and beach type sediments. Direct push methods are generally successful at penetrating clays, silts, sands and some gravel. Deposits such as soils with thick caliche layers, or glacial tills with large cobbles or boulders may be difficult or impossible to penetrate to the desired depth. Direct push methods are not designed for penetration of consolidated bedrock such as limestone, granite or gneiss.

Note 1: The quality of the result produced by this standard is dependent on the competence of the 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.

Practice D3740 was developed for agencies engaged in the laboratory testing and/or inspection of soils and rock. As such, it is not totally applicable to agencies performing this field practice. However, user of this practice should recognize that the framework of Practice D3740 is appropriate for evaluating the quality of an agency performing this practice. Currently there is no known qualifying national authority that inspects agencies that perform this practice.

Subcomité:

D18.21

Referida por:

D6771-21, D6286_D6286M-20, D8571-24, D7663-12R24, D6724_D6724M-16R24E01, D6001_D6001M-20, D7929-20, D5092_D5092M-16R24

Volúmen:

04.09

Número ICS:

13.060.10 (Water of natural resources)

Palabras clave:

aquifer; direct push; groundwater; monitoring well; prepacked screen; water quality;