What’s the solution?

The Coal Authority is a recognised expert in the treatment of mine water and has constructed over 80 mine water treatment schemes across the UK, all individually designed to meet the requirements of the mine water and the location.

The solution for the mine water discharge at Dalkeith is to construct an active High Density Sludge (HDS) mine water treatment scheme. This solution is driven by several factors:

• the concentrations of iron and the presence of other minerals in the mine water, such as manganese
• the limited land available
• the flow from the adit

An active treatment scheme is the only option that will guarantee the  removal of both the iron, and at a future date the manganese, from the mine water. It provides the lowest cost option for treatment of the mine water and returning the flow to the South River Esk ensures that the river is not depleted of water.

Layout of the interior of the plant

The active treatment scheme will be located local to the existing adit on the Junkies Day Level Adit site, which is the property of The Coal Authority. A new underground capture structure and pumping well would allow the abstraction of flows from the adit for treatment and returning the treated water to a similar location where the current adit discharges. The river will naturally recover from the damage caused by mine water pollution over time.

Given the positives of lower cost, limited water transport, operational flexibility, future proofing, land ownership and certainty of treatment, this is the most favoured option. The rendered image created by our digital team below shows the full process.