Successful water treatment trials in South Crofty tin mine

8 Jun 2017

Siltbuster Process Solutions (SPS) has been engaged by Strongbow Exploration Inc following successful trials showing the treatability of mine water from the closed, flooded tin mine at South Crofty in Cornwall. The trials have proved the viability of dewatering and the company has subsequently applied to the Environment Agency for a mine water discharge permit. Once fully permitted, the mine will be dewatered over an 18-24 month period ahead of reopening.

The mine water includes dissolved contaminates and metals in solution (principally iron) which will be removed. The trial phase used SPS’s High Density Sludge process to treat 18 cubic metres per hour of mine water which provided performance data to support Strongbow’s discharge consent permit application and also will be used in the design of the full-scale plant to treat and discharge up to 25,000 cubic metres of mine water per day into the local Red River.

“This is an important step in the development of our South Crofty project and will enable Strongbow to begin construction of the water treatment plant, subject to financing, as soon as we receive the discharge permit from the Environment Agency. The company expects to receive the discharge permit later this year, and commence dewatering of the mine in the first half of 2018, as planned,” CEO Richard Williams stated in a press release.

SPS is a recognised world authority in treating mine water. It has successfully completed many mine water treatment plants, designs and feasibility studies both in the UK and worldwide in Greece, the Slovak Republic, France, Canada and Australia. These include Wheal Jane, Cornwall, UK, one of the largest active mine water treatment projects in the World, which over the last 14 years has involved treating over 100 million cubic metres of water. SPS also designed the Dawdon mine water treatment plant for the UK Coal Authority, which won the 2010 Eddie Award for the best water treatment plant in the UK. Earlier this year we finished a turnkey contract to design, construct and commission a water treatment system for Wolf Minerals’ new tungsten mine at the Drakelands Mine, near Plymouth in Devon, the 4th largest tungsten deposit in the world.

Commenting on South Crofty, Chris Bullen, Technical Manager for Siltbuster Process Solutions said: “It is great to have been chosen to work on such an important and high profile project. We have a long history not only of working with mines but also of this region, we understand the local geology and have consulted heavily with the Strongbow team on the best way to dewater the mine.”

The South Crofty tin project area covers 1,490 hectares, and includes 26 former producing mines. Production records for the site date back to 1592 with full scale mining activities commencing in the middle of the 17th Century. The mine closed because of the tin price, which collapsed in 1985. Strongbow acquired South Crofty in July 2016.