Grout Treatment Facility Borehole Summary Report ... - Hanford Site

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WHC-MR-0203
DRILLING
Both wells were drilled by Kaiser Engineers Hanford using the cable-tool
drilling method. A drive barrel was used for drilling and sampling unless
the material was too coarse to be removed by the drive barrel. In that case,
the hard-tool bit was used, and samples were obtained via a bailer. All
drill cuttings generated below the water table were contained. The borehole
was kept open with temporary carbon steel casing. Pacific Northwest
Laboratory (PNL) geologists were responsible for well installation
documentation and sample collection and description. The as-built diagrams,
geologist's logs, and well completion/inspection reports are shown in
Appendix A. Lithologic samples were collected at 5-ft intervals or at
changes in lithology. Samples for analysis of percent moisture were
(.. collected concurrent with lithologic samples during drive-barrel drilling,
provided the moisture content of the sediments was representative (i.e., if
,.•.
no water was added by the driller). Moisture sample data are shown in
Appendix B. The elevated moisture content shown in these data generally
corresponds to intervals of finer-grained sediments. Samples for possible
chemical analyses were collected at approximately 20-ft intervals or at
changes in lithology. A total of 30 samples were collected, 13 from well
299-E25-37 and 17 from well 299-E25-38. Twelve of these samples were
analyzed by United States Testing Company, Incorporated, for anions, total
organic carbon (TOC), gross alpha, and gross beta. No unusual results were
^- reported. Appendix B contains the chain-of-custody forms and analyses data
cl, for these samples. Sieve analyses were conducted on samples within the
screened interval at both of the wells. These results are also shown in
Appendix B. Both wells were logged with the natural gamma geophysical probe.
These logs are shown in Appendix A. During the drilling of both of the
wells, onsite monitoring was conducted using Geiger-MUller radiation
detection meters and organic vapor analyzers. No contamination was detected
by these instruments. Nonconformance/surveillance reports are shown in
Appendix C. The following paragraphs summarize the specific drilling history
of each well.
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