According to the government, abandoned mines release at least 500 tonnes per year of toxic metals into the Welsh environment.
According to Natural Resources Wales, a Freedom of Information Request revealed that 129 sites “certainly or highly likely” are causing the failure of water quality criteria.
The Welsh government has estimated that “350-500 tons” of metals are released annually from the 129 sites.
This indicates that Wales’s more than 1,300 abandoned site discharges is likely to exceed 500 tonnes.
The abandoned mines are responsible for polluting 700km of rivers with lead, zinc, and cadmium. The figures have prompted calls for the UK to take action against the legacy of Britain’s mining past.
Ben Lake of Plaid Cymru, who represents Ceredigion, said that the severity of the findings is a national concern and demands urgent attention from both Welsh and UK government.
The metals released by these mines can accumulate on the soil and floodplains used to produce food and homegrown crops.
Last year, a study published by NRW revealed harmful levels of lead found in eggs at two small farms located downstream from abandoned lead mining in West Wales.
The study found that children who eat one or two eggs per day could “become cognitively impaired”. The study’s academics claimed that the eggs are eaten at the farms and sold locally.
According to the World Health Organization, there is no known level of exposure to lead that does not cause harm.
The findings of the study prompted the Welsh Government to hold two meetings with officials across the UK last year, including the Food Standards Agency as well as the Health Security Agency.
“Ministers of government, members of relevant public institutions and scientists should meet immediately to determine the actions necessary to minimize any risk to the public’s health. Lake said that there is no time to waste.
Official estimates show that nine of the ten most polluted metal mine catchments in Britain are located in Wales.
Mark Macklin from the University of Lincoln described the situation as the “tip of the iceberg” in Wales.
Macklin stated that “in the UK, the focus of recent attention has been microplastics and wastewater but metal contamination due to historical mining dwarfs the issue both from a perspective of ecosystems and human health.”
According to the British Geological Survey database, there are approximately 8,500 metal mines that have been abandoned in Great Britain.
Metal Mine Strategy for Wales, published in 2002, identified 50 abandoned mines that were having the most impact on rivers.
Since then, NRW only completed one major remediation project on Frongoch in Ceredigion. It also completed smaller-scale remediation works at two other sites.
NRW estimated in 2016 that the Frongoch Mine still released 16,000kg, or 16 tonnes of metals each year. This is only a partial reduction from the 21,000kg prior to the remediation.
In the UK, dealing with this issue can be complicated because local authorities are responsible for identifying contaminated land which could pose a health risk.
Macklin, from Lincoln University, led a study that was published in September 2023. It estimated that as many as 557, 000 people live in a floodplain in the UK contaminated by historical metal mining.
According to the models used in the study, the area of potentially contaminated flooding plain was approximately 1,120km sq., which is 10 times larger than the city of Manchester.
“There have been. . . Macklin said that there has been little recognition of the fact that floodplains are a bigger problem than mines or watercourses immediately downstream.
The UK government is primarily responsible for the cost of cleaning up abandoned mines, as mine operators were allowed to abandon sites until 1999 without being required to do so.
Dave Johnston is NRW’s senior expert adviser on abandoned metal mines. He said: “Natural Resources Wales, the Coal Authority, and other stakeholders are working together to combat this pollution and reduce other hazards in these mines.
He added that “we are actively working on the 25 projects of the programme”, noting that certain projects covered multiple mine sites.
In England, the Water and Abandoned Metal Mines Programme (WAMM) was created in 2011 to develop programs to treat abandoned mine water pollution. Officials stated that the program currently operates three successful mine-water treatment schemes which have improved 20kms of rivers.
The UK government announced a new legally binding target in January 2023: “Halve the lengths of rivers polluted with abandoned metal mines before 2038”.
Rebecca Sudworth is the director of policy for the Food Standards Agency. She said, “Businesses should ensure that the food they are producing does not exceed the maximum lead levels set out by law.”
She added, “We have implemented a monitoring system and a testing program to ensure that the maximum lead levels in food are not exceeded. Local authorities can take enforcement action if these levels are exceeded.” The Department for Environment, Food & Rural Affairs refused to comment separately.
Welsh government spokesperson stated: “Local governments have a responsibility to identify contaminated soil within their area.” They have a responsibility to deal with contaminated land if they find it.