Frequently Asked Questions

Questions and answers will be updated to reflect changing interests, concerns, and conditions as the project moves forward between now and 2011, so please visit often.

The Partnership and Facilities
Site Selection
Facility Operations
Environmental Protection and Regulatory Process
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Pipeline
Geotechnical Investigations

Geotechnical Investigations

1.    What are borings?

       Borings are 2-inch to 8-inch diameter holes, drilled into the ground to determine conditions at depths where structures and piping are to be located.

2.    Why are geotechnical investigations necessary?

Geotechnical evaluations are necessary to determine whether pipe and structures can be adequately supported, the type of excavation that will be required, the depth to groundwater and other geological features that impact design and construction.

3.    What types of equipment are used for geotechnical investigations?

Normally drilling equipment is used, similar to what would be used to drill a residential well.

4.    How much noise will the equipment make?

Drill rigs for borings are normally run by internal combustion engines and therefore would produce noise levels comparable with a large truck.  For about an hour or two during the drilling process for a boring, the drill crew will take split spoon samples which will sound like a small hammer hitting a steel pipe for 30 to 60 seconds, at intervals of 10 to 15 minutes.  The noise is generated by a soil sampler being driven into the ground to evaluate the type and hardness of soil and rock underground.  Although not as loud, the noise during these periods may sound like a pile driver, but no piles are being driven.

5.    How long does it take to conduct geotechnical borings?

Depending on the depth and nature of the material underground, one to three days may be required to complete a boring.

6.    Will the borings cause property damage?  How will the drilled holes be backfilled?

The borings will cause no property damage.  Boring locations are selected to facilitate access by the drilling equipment.  This minimizes the impact of having the equipment on the property.  Depending on what is appropriate for each bore hole, a cement slurry, special clay pellets, or material removed from the hole will be used to fill the hole.  Soil will be used to fill the hole at the ground surface, and it will be tamped and finished smooth to prevent a tripping hazard for people or animals.