Water Well Drilling
It is in your best interest to check that the Water Well Drilling Contractor:
- Has reliable and comprehensive machinery to handle varied and unpredictable groundwater drilling conditions.
- Considers local drilling records to ascertain likely water well drilling conditions applicable to your site.
- Undertakes a site survey to consider drill rig access, potential implications of drilling near buildings and/or existing wells.
- Suggests an appropriate location for proposed well, in adherence with various guidelines in order to facilitate groundwater protection efforts.
- Provides a written quotation clearly stating terms and conditions.
- Clarifies queries at site survey stage e.g. cement sealing of water well, well disinfecting, specification of steel and plastic casing to be used. Make sure an adequate borehole log will be recorded.
- Issues advice on manhole completion, pump installation & water testing and associated treatment systems.
- Clarifies what the drillers undertaking is if the borehole does not produce a minimum domestic water supply eg. 200 gallons per day.
Advisory Groundwater Services
General information on water well drilling & borehole construction methods, also information on private well grants.
Site Specific Survey
Each site will be surveyed in advance of quotation issue including reference to existing groundwater drilling records of the area.
Clear, unambiguous written quotation, including Drilling Contractor's responsibilities guarantee and disclaimers.
The Consumer should be offered as an optional extra well sealing by either:
(a) Grout band ; steel band placed below steel liner attached to outside of the uPVC casing, with bentonite pellets emplaced from the top of the grout band (outside uPVC casing) say 3-5 metres up into the inside of the steel casing. See middle diagram of three above.
(b) Grout by tremie pipe injection; using Grouting equipment to mix cement grout into slurry form and injecting it through circa 1" tremie pipes below bedrock, displaced into rock fissures back to surface in one continuous operation.The grout is supported by a column of clean gravel outside the uPVC screen section and injected above 1 mtr sand layer which overlies the top of the gravel formation pack . See diagram to right of three above.
Note: Well sealing is particularly effective where drilling conditions are stable and grouting extends from a discrete depth into competent bedrock to surface.
A concentrate of Well Disinfection to be recommended with clear instructions of its useage on completion of each well.
Well Head Protection
An Instruction sheet describing well head works (including manhole finish) should be made available to each Customer.
A list of Specialist Pumping Contractors maybe provided with proven on-hand expertise and back-up support local to your area.
Advisory Services on who to contact and steps to take to secure an effective treatment system.
One Drilling Contractor's water well is the same as another Drilling Contractor's water well - NOT NECESSARILY!.......... consider:
- Gravel/sand,unstable formation. Is the borehole sufficiently deep and adequately developed in ther gravel aquifer to ensure long term sustainability of water supply?
- Is the borehole properly logged?
- Are water strikes containing fines and silt in top section of borehole satisfactorily closed out by driving nonperforated steel casing beyond these inlets?
- Are welded joints between steel casings adequate to withstand hammering into position?
- Is the borehole vertical or does it shoot off-vertical below ground level?
- Are steel lining & plastic lining certified materials (ie. fit for purpose)?