The company that runs Stanlow oil refinery has admitted pollution breaches at the installation near Chester.
Essar Oil, which runs the second largest oil refinery in the UK at the Cheshire plant, pleaded guilty at Chester Crown Court to three counts of breaching its environmental permits during two separate incidents there in 2012.
In the first, on July 31, 3.7 tonnes of oil were sprayed into the air in a plume of steam after a storage tank exploded on under pressure.
In the second incident on August 19, five tonnes of oil were deposited into the Manchester Ship Canal, adjacent to the site.
A sentencing hearing took place on Friday and the firm will discover how much it will be fined this week.
Richard Bradley, prosecuting told the court how in the first incident the mixture of oil and steam covered an area of Ellesmere Port approximately 5.8km long and 0.8km wide.
At its furthest point it covered 7,500 gravestones in a film of oil and water at Overpool Cemetery.
Mr Bradley said the explosion occurred after “catastrophic failure” in the process at the refinery.
He said the plant was producing long residue oil – a intermediary in the process of making oil products – for storage. This can be stored in a hot or cold form.
He added that the plant was running out of storage in the hot tanks and had to cool the oil down so it could be stored in the cool tanks.
Operators started a process called ‘slipstreaming’, which mixes the hot and cold oil together to cool it down, Mr Bradley explained.
He said this was a procedure the plant didn’t follow very often and had only been used three times previously.
Two teams were required to run the operation, Mr Bradley said, but neither had familiarised themselves with how to run it.
This led to hot oil going directly into a cold tank. At 7.20pm on July 31 an alarm went off in the control room warning that the temperature was too high in the tank.
Mr Bradley said that after an initial investigation, which measured the temperature of the wrong input to the tank, it was assumed that the temperature gauge was faulty.
Water began to boil and at 8.30pm the tank, which was designed to fail under pressure, exploded, releasing the mixture of oil and steam.
Essar reported the incident to the Environment Agency and Mr Bradley said that Cheshire West and Chester Council’s environment team received a huge number of complaints from people whose homes and cars were covered in a film of oil from the blast.
The council issued advice to residents to wash their hands if they came into contact with the oil and not to let their pets or children on to grassy areas.
Mr Bradley said the concentration of the oil was very low and didn’t pose a risk to human health.
Essar spent £1.2 million on a clean-up operation in the area in the days after the incident.
The August 19 incident happened in a separate part of the plant.
Mr Bradley said a system which is supposed to filter out excess water from oil before being released into the canal failed and as a result, the system was overwhelmed with oil.
He said that a tank which pumps off oil that sits on top of the water wasn’t working properly, so ‘gully suckers’ had to be used to remove the oil before going through some further processing.
However, the plant did not have an effective system of measuring the quantity of oil in the water and so did not pump off the oil often enough.
This led to oil overwhelming the system and being released into the canal.
Mr Bradley said the oil was “extremely flammable, harmful to aquatic life and a level two carcinogen”.
As a result of the spill, Essar paid £210,000 to clean up the canal, which was closed for two days, and two swans had to be cleaned by the RSPCA.
Mr Bradley described the company as “negligent”, but said that Essar, which had a turnover last year of £6 billion, had pleaded guilty at the first opportunity, had co-operated with the investigations and paid clean-up costs.
Nicolas Cole, defending, apologised to the court and to the community on behalf of Essar.
He said: “I start with an apology to the court and to the local community because Essar is a company which is founded in its community.
“It is a large local employer and has strong links with that community. Particularly in respect of the first incident, there was a impact on that community and we want to proffer our apologies.”
Mr Cole said the company had accepted responsibility of what he described as “procedure failings” and had pleaded guilty.
Source: The Standard 25th November 2015
He said that Essar, without hesitation, had paid all the clean-up bills and had co-operated fully with the investigations.
He added that despite a high turnover, the company has lost £10m in the last four years and asked for any fine to take that into consideration.
Judge Raj Shetty said he “didn’t want to put jobs at risk”, but would take a week to determine the level of the fine to the company.
Source: The Standard 25th November 2015