RE150050

Tender description

The Natural Environment Research Council (NERC), through its centre/survey the British Geological Survey (BGS – known hereafter as “The Authority”), invites tenders for the provision of drilling services to support project monitoring and research activities. The purpose of the project is to improve the understanding of movement of fluids and possible chemical changes in aquifers and overlying strata. It is planned that the work shall be carried out in four to six sites in total to the east of Blackpool, around Elswick, Lancashire. NGR: 3422 4383 (SD43) (indicative only), and around Little Plumpton NGR 3374 4327 (SD33) (indicative only). If the preferred sites are not accessible to The Authority, any alternative site shall be in the area of a radius of approximately 5 miles of the above. At the sites, a pair of boreholes shall be required to provide: a. Improved understanding of the superficial (‘Drift’) geology, b. Sample returns from the boreholes to be sub-sampled and processed, c. Pairs of completed boreholes to be used as monitoring boreholes for scientific purposes. It is planned to drill the pairs of boreholes from Ground Level (GL) to a Total Depth (TD) of approximately 40m and 10m adjacent to each other (within 2m, see Section 4 below and “Site Conditions”). On reaching TD the deeper boreholes may be geophysically logged, before being completed. Suitably specified permanent casing will be required in the upper section to prevent collapse and 100mm internal diameter plastic casing with a 2m slotted interval with suitably graded gravel packing in the lower part of the boreholes.