Borehole wash water reuse?
We are looking at possible options for reuse of water that has been used to clean an operational borehole. The water will be high in chlorine and turbidity. Assuming that there is no legislation to cover this, and that the community is happy, is it possible to reuse this water in agriculture for human consumption? If not, any other options other than discharging into the environment? I think that treatment options for reducing the chlorine load are not economically feasible considering the large amount of water. Any thoughts?
Have you concluded that sodium metabisulfite and sodium bisulfite are too expensive? The application can require nothing more than a bag to hold some tablets in the water stream. Otherwise discharging into a watercourse is could have fish-kill & other ecological implications.
Are the community, and all other potentially affected communities, happy after fully understanding the repercussions?
I am a bit confused as to why the water will be chlorinated. Usually borehole development involves pumping out from the borehole with the water in the aquifer. Or are chemicals being added to develop the borehole in flow etc.?
If you are adding chlorine to achieve this it is feasible to dechlorinate. This does not have to be done by chemical dosing to a flow but can be by putting flow through a chamber with bags of sodium sulphite etc as Martin suggests.
For reuse for agriculture I would suggest de-chlorination and to reduce the suspended solids load through settlement .
This thread is public, all members of KnowledgePoint can read this page.