Standard Guide for Use of Cable-Tool Drilling and Sampling Methods for Geoenvironmental Exploration and Installation of Subsurface Water Quality Monitoring Devices

Importancia y uso:

4.1 Cable-tool rigs (also referred to as churn rigs, water-well drilling rigs, spudders, or percussion rigs) are used in the oil fields and in the water-well industry. The Chinese developed the percussion method some 4,000 years ago.

4.2 Cable-tool drilling and sampling methods may be used in support of geoenvironmental exploration and for installation of subsurface water quality monitoring devices in both unconsolidated and consolidated materials. Cable-tool drilling and sampling may be selected over other methods based on its advantages, some of which are its high mobility, low water use, low operating cost, and low maintenance. Cable-tool drilling is the most widely available casing-advancement method that is restricted to the drilling of unconsolidated sediment and softer rocks.

4.2.1 The application of cable-tool drilling and sampling to geoenvironmental exploration may involve sampling unconsolidated materials. Depth of drill holes may exceed 900 m [3000 ft] and may be limited by the length of cable attached to the bull reel. However, most drill holes for geoenvironmental exploration rarely are needed to go that deep. Rates for cable-tool drilling and sampling can vary from a general average of as much as 7.5 to 9 m/h [25 to 30 ft/h] including setting 200 mm [8 in.] diameter casing to considerably less than that depending on the type(s) of material drilled, and the type and condition of the equipment and rig used.

Note 2: As a general rule, cable-tool rigs are used to sample the surficial sediments (that is, overburden), and to set surface casing in order that rotary-core rigs subsequently may be set up on the drill hole to core drill hard rock if coring is needed.

Note 3: 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 facility used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some, but not all, of those factors.

4.2.2 The cable-tool rig may be used to facilitate the installation of a subsurface water quality monitoring device(s) including in situ testing devices. The monitoring device(s) may be installed through the casing as the casing is removed from the borehole. The sand line can be used to raise, lower, or set in situ testing device(s). If necessary, the casing may also be left in the borehole as part of the device.

Note 4: The user may install a monitoring device within the same borehole wherein sampling, in situ, or pore-fluid testing, or coring was performed.

Subcomité:

D18.21

Referida por:

D6286_D6286M-20, D6001_D6001M-20, D5092_D5092M-16R24

Volúmen:

04.08

Número ICS:

13.060.10 (Water of natural resources)

Palabras clave:

cable-tool drilling; drilling method; geoenvironmental exploration; groundwater; vadose zone ;