Veolia, the UK’s largest waste company, was fined over £100,000 in January following an incident at its Bootle hazardous waste treatment plant that caused four people to be hospitalised.
According to the Environment Agency and Health and Safety Executive (HSE), which jointly brought the prosecution, the incident revealed multiple failures in the company’s procedures. The site’s emergency plan was inadequate and the staff’s response to the incident hindered the emergency services.
The Bootle plant is permitted to handle 75,000 tonnes of waste per year and is a lower-tier site under the Control of Major Accident Hazard (COMAH) Regulations. In April 2006, Veolia accepted waste containing hydrobromic acid, despite the site the not being allowed to take this under its waste licence.
Most waste was treated in the site’s acid-neutralisation plant, but on 27 April four tonnes remained in a storage tank. That day, the company received 18 tonnes of nitric acid wastes. Nitric acid is highly reactive and many sites do not store it with other materials. However, the site chemist carried out a compatibility test and gave the go-ahead for the acids to be mixed.
During testing, the chemist simply mixed the acids in a beaker and held it in his hand to see if the temperature increased. According to HSE inspector Daniel Longdon, who dealt with the case: "This wasn’t adequate, but it was in line with the firm’s procedures at the time."
By 4pm a runaway exothermic reaction had begun in the storage tank. The site’s alarm system was activated by an employee who thought he smelt chlorine. However, staff were sent back to work while this was investigated. Another alarm was raised and four members of staff, including the site manager and his assistant, went into the acid-neutralisation plant to investigate. All four were overcome by the fumes.
According to Mr Longdon, key staff members should not have entered the plant together leaving no one to coordinate the incident response. Had the site’s training and emergency plan been adequate they would not have done so.
The plant’s scrubbing system was quickly overloaded, resulting in a release of gases which may have included bromine as well as nitrogen dioxide. The effects were felt as far afield as Anfield.
The fire brigade attended the incident but could not bring the reaction under control until 8am the next day because the storage tanks were mislabelled on the site plan. Firemen spent several hours trying to pump material from a redundant tank.
Appearing before South Sefton magistrates court, Veolia pleaded guilty to eight charges: three under the Health and Safety at Work etc Act 1974, one under the Management of Health and Safety Regulations 1999 and four under section 33 of the Environmental Protection Act 1990. It was made to pay £65,000 costs on top of £101,000 in fines.
Charges included failing to ensure the public were not exposed to toxic fumes and breaching conditions of its waste licence.
Agency officer Mark Easedale said: "Hopefully the fine reflects the severity of the incident and should send a message to the hazardous waste industry that effective systems should be in place to ensure compliance with conditions of environmental permits."
According to Mr Longdon, Veolia has improved procedures at the site. Compatibility tests have been made more sensitive to heat changes and now include analysis of gases released.
The company has also stopped storing nitric acid with other materials. The site’s emergency plan has been updated and staff have received training to ensure it is implemented.
No major incidents have since occurred at the facility. But the HSE served the site with a prohibition notice last September for taking samples of waste from the rear valve of road tankers. These are not considered representative of the load and the company must now use a gantry to take samples from the top of tankers.
The first incident in 2007 was caused by the site’s overloaded wastewater treatment plant, the second in 2008 by a failed biogas flare. Residents said the incidents produced a smell "almost like a dead rat".