Salmon and water supplies could be at risk from Sperrins mine waste facility, inquiry hears

Objectors to a proposed gold mine in the Sperrin mountains have said a Stormont department is failing to properly assess the potential risks from a 50-metre-high waste facility.

The concern was levelled directly at the Department for Infrastructure (DfI) as the public inquiry into Dalradian’s mine application continued in Omagh this week.

Marella Fyffe, chair of community group Save Our Sperrins, asked whether the local community was “just mere collateral damage”, as four days of evidence on mine waste plans, drainage, and other topics concluded.

Multinational company Dalradian Gold hopes to mine gold and other metals in the Sperrin Mountains for more than 20 years.

Millions of tonnes of waste from the proposed mine would be kept in a “tailings” facility designed to permanently store the leftover ground rock, fluids, and processing chemicals.

However, third party objectors said they feared lives and livelihoods could be lost if the facility collapsed during a storm or heavy rainfall.

It has now emerged that DfI - which will make the ultimate decision on the planning application - does not think the waste facility should be categorised as a “Category A” level of risk.

Dalradian maintains there is “no credible pathway” to failure of the waste facility, based on its own models.

Objectors argued that Northern Ireland’s high rainfall levels, which are set to rise with climate change, could turn the tailings into a “fully liquefied mass” and questioned the use of rainfall data gathered at a weather station 20 miles away at Lough Fea.

Third parties raised concerns about the lifespan of materials such as drainage pipes that would be used to drain the tailings stack, which is intended to remain in perpetuity.

It was also suggested any failure could impact water supplies for tens of thousands of homes as well as the Foyle river system and endangered freshwater pearl mussels.

Ms Fyffe added: “The community is taking all the risk and the company is receiving all the benefits.”

Fermanagh and Omagh District Council’s barrister, Conor Fegan, urged caution around interpreting the legislation, which he said uses the lower threshold of “could” in terms of a major incident arising from failure or incorrect operation, rather than “likely” or “would”.

He said if commissioners “cannot rule [risk] out on a precautionary basis - then the correct conclusion is that it is a Category A facility.”

The inquiry also heard from the Loughs Agency’s head of science, Dr Sarah McLean. She outlined how a "catastrophic failure entering surface waters of the Pollanroe and Owenkillew SAC… could give rise to deleterious impacts on critical fish species” like the Atlantic Salmon.

She agreed the waste facility should be Category A as any such incident could be “an unmitigated loss” for salmon with “unique genetic markers”.

Dalradian counsel, Stewart Beattie, told the inquiry: “We do not accept the categorisation of the Loughs Agency where it will affect Atlantic salmon.

“We say the failure modes that are conceivable were identified and they were assessed consistent with the regulations.”

Jamie Spiers from SRK Consulting, which produced geotechnical reports for Dalradian’s proposed mine waste facility, outlined how the only “credible failure mode” related to the waste stack was a “stability-based sump failure”.

Peter Corrigan, from WSP consultancy acting for DfI, said he came to the conclusion this was not a Category A waste facility “based on my own understanding on what a failure would look like”.

Waste rock discrepancies

The inquiry also heard evidence of discrepancies around the tonnage of waste rock to be generated as Dalradian mines the Curraghinalt gold deposit.

Figures cited ranged from 4.8 million to 5.8 million cubic metres of rock, with questions raised about the consistency by third party objector and local farmer, Pat Haughey.

Objectors suggested that DfI and Dalradian were "designing to suit" their own parameters rather than taking a precautionary approach.

According to a mine waste rebuttal report by SRK for Dalradian, dated November 2024, the tailings stack is created by spreading, drying and compacting waste rock into an engineered form.

Professor Emerman asked: “What is going to be done with tailings that are too wet for compaction? How often is it going to be raining? I haven't seen that anywhere.”

Mr Spiers responded: “Each cell has many days storage. When the weather is wet, we have multiple lines of redundancy to deal with wet conditions.”

It emerged that Alaska’s Greens Creek silver mine, which was referenced in Dalradian’s environmental statement as an example of constructing and managing a tailings facility in a wet climate, was fined $143,000 by the US government for lead pollution.

Concerns were also raised about some data provided in Dalradian’s mine waste plans, with Commissioner McParland asking if the applicant planned to provide new figures “on the hoof”.

Mr Spiers issued corrections on statistical totals for waste in the mine waste management plan after Sean Tracey of Communities Against Mining highlighted how they didn’t add up last week.

He said it was an Excel fault, adding: “The numbers are not changing. The totals are wrong.”

“Guesswork”

While proceedings focused largely on the waste rock tailings facility, objectors also argued early last week that the project’s viability is based on “guesswork” rather than independently verified reserves.

Speaking for Save Our Sperrins, mining expert Professor Emerman said Dalradian had not established that the resource was economically viable.

Dalradian’s counsel, Stewart Beattie, disagreed. He said the Geological Survey for Northern Ireland (GSNI) “has confidence in the approach” while SRK Consulting project manager John Merry said “there is no doubt the material is there”.

Mark Patton from GSNI told the Planning Appeals Commission that Dalradian had “increased confidence on statements as to what was there” through drilling, and that there could be more or less ore than predicted but that “there is still an element of uncertainty”.

He also said independent tests are “not within” GSNI’s “remit”.