Environment Agency officers say water quality at ponds in Shipley Country Park has returned to a ‘safe drinking level’ after the recent chemical spill.
Experts have been monitoring the impact of an accidental spillage of 400 litres of liquid cyanide from a lorry delivering to an industrial unit in Heanor, some of which leaked into the nearby Adam’s Pond.
Tests have revealed the water has now returned to a ‘safe drinking water’ quality and signs to stay out of the two affected ponds have been removed.
Drinking water quality does not mean it is recommended to drink the pond water – it means the concentrations of cyanide currently monitored are below these standards.
Since the incident occurred, the Environment Agency has been regularly collecting samples from numerous ponds on the site and sharing the results with Derbyshire County Council, which owns the park, and Public Health England.
Greg Oakes, area duty manager at the Environment Agency, said: “Samples have regularly been taken to monitor the cyanide levels in the water and the results of the latest samples show the water is now at a drinking water quality, which is an excellent result.
“However, we would stress, drinking water standards does not mean we would recommend drinking the pond water, it is just that the concentrations of cyanide currently monitored are below these standards.
“The contamination was largely contained to Adam’s Pond, which unfortunately resulted in a number of dead fish being found in the pond but, due to the level of contamination, our staff were unable to enter the water to carry out a netting activity to capture them. Whilst our monitoring showed there was some discharge to the nearby Osbourne’s pond, this did not result in any dead fish being found there.
“In light of the latest results, rather than continuing with monitoring on site, we will now put a recovery plan in place.
“Adam’s Pond is still closed to fishing to allow the water life to recover and the Environment Agency will meet with the county council and the local fishing club next month to discuss a management plan for the pond.”
A report by Environment Agency National Centre for Environmental Toxicology confirmed there was no significant risk to other wildlife which may have eaten dead fish from Adam’s Pond.
Councillor Simon Spencer, Derbyshire County Council’s cabinet member for highways, transport and infrastructure, said: “This must not be allowed to happen again and we’re pleased there will be an investigation and action taken against those responsible to send a clear message to businesses that they need to take their environmental responsibilities seriously.”