Farmer's land which is due to be dug up for offshore windfarm cables has previously carried a 'radioactive risk' following a plane crash 22 years ago, secret documents reveal today.

Vattenfall, the firm behind proposals for the massive windfarm off the east Norfolk coast, has been criticised after it emerged it did not even know about the crash on land near Necton - and that it plans to carry on with the dig regardless.

The company has allayed the fears of people living nearby and says any potential risk is 'unlikely'.

A Danish F-16 fighter jet crashed into the sugar beet field between Necton and Ivy Todd on December 11, 1996 after taking off from RAF Marham.

The land was contaminated with fuel at the time and could not be used for farming for several years.

Eastern Daily Press: This map from Vattenfall shows where the energy firm wants to dig a cable trench and build new substations near Necton. The red circle shows the site of the F-16 crash. Image: Vattenfall/ArchantThis map from Vattenfall shows where the energy firm wants to dig a cable trench and build new substations near Necton. The red circle shows the site of the F-16 crash. Image: Vattenfall/Archant (Image: Archant)

But newly unearthed documents from 1996 show the Ministry of Defence warned of a 'radioactive substance risk' at the crash site.

Despite this, the site could now be dug up by the Swedish energy company to bury cables at least one-metre deep and build substations for its huge offshore wind farm.

Vattenfall wants to dig a cable trench 60 kilometres long from Happisburgh, where its cables come ashore, to Necton, where the cables will connect to the National Grid.

The company says it has looked at the risk of contaminated land for the project overall, but not at this site as it did not know about the plane crash until being told by campaigners in July.

Eastern Daily Press: The plane crash sparked a military investigation. Photo: Archant LibraryThe plane crash sparked a military investigation. Photo: Archant Library (Image: Archant Library)

Campaigners are now urging them to leave the land alone.

Farmer Colin King, who has land near the site, was feeding his pigs when he heard loud booms from the crash almost 22 years ago.

'It really upsets me to think that through a lack of research they are going to start disturbing the land,' he said.

'Hopefully the contamination is all gone, but the cable trench runs directly through the crash site.

Eastern Daily Press: Emergency services on the scene of the crash in December 1996. Photo: Archant LibraryEmergency services on the scene of the crash in December 1996. Photo: Archant Library (Image: Archant Library)

'For them to have not picked up this major crash in their reams of work is crazy.'

Vattenfall had to carry out an environmental assessment for the wind farm and submitted it to the Planning Inspectorate last month. But it did not include this crash as it did not know about it.

It said if it did come across any contamination during the work there would be protocols 'to ensure it is dealt with safely prior to construction starting'.

'We did receive anecdotal reports of the crash shortly before submission of our application, but publicly available information did not verify details of the crash or its location,' a spokesman said. 'In addition, it was not raised by statutory consultees.'

Eastern Daily Press: Jenny and Tony Smedley near the proposed site for the substations in Necton. Photo: Colin KingJenny and Tony Smedley near the proposed site for the substations in Necton. Photo: Colin King (Image: Archant)

Residents remember men in contamination suits closing off the area after the land was polluted with jet fuel called Hydrazine.

Hydrazine is highly toxic and can cause 'systemic poisoning and permanent kidney damage' if not handled properly, according to a Ministry of Defence report into the crash, which has been released under the Freedom of Information Act.

Jean Bass, who was on Necton parish council at the time, said she remembered the land could not be used for farming for several years.

'We got a report from RAF Marham,' she said. 'They said the land was contaminated with aviation fuel and it was seven years before they could grow anything.'

Eastern Daily Press: The F-16 which crashed at Necton. This photo was taken the day before the crash on December 11 1996. Photo: Archant LibraryThe F-16 which crashed at Necton. This photo was taken the day before the crash on December 11 1996. Photo: Archant Library

But the newly unearthed document shows the crash site could have been contaminated with more than just aviation fuel.

A fax from the National Rivers Authority to the Environment Agency on the afternoon of the crash states the Ministry of Defence had told the Ministry of Agriculture, Fisheries and Food of a 'radioactive substance risk'. It gives no more details than that.

The radioactive risk could come from depleted uranium which is used in missiles carried by aircraft. Depleted uranium is still used in weapons today and is made from waste material from nuclear power plants.

It is unclear what risk, if any, it would contain today, but Jenny Smedley from the Necton Substations Action Group, who uncovered the documents, urged Vattenfall to not dig up the area.

Eastern Daily Press: The crash left a crater and the land was contaminated with fuel. Photo: Archant LibraryThe crash left a crater and the land was contaminated with fuel. Photo: Archant Library (Image: Archant Library)

'We think Vattenfall should be made to change their plans to excavate in the area, because it will be impossible to discover what's there without disturbing it.

'Our biggest worry is that any disturbance even some distance from the crash site could change the water table.'

The 1996 fax from the National Rivers Authority said water supplies should not have been contaminated.

The Vattenfall spokesman added they were 'confident that the assessment of potentially contaminated land as presented within our environmental assessment is robust'.

Eastern Daily Press: An F-16 Fighting Falcon. Picture: US Air Force photo/Tech Sgt Matthew PlewAn F-16 Fighting Falcon. Picture: US Air Force photo/Tech Sgt Matthew Plew (Image: Archant)

•'Our lucky day'

The Danish F-16 Fighting Falcon was at the end of a visit to RAF Marham when it took off from the airbase heading home on the morning of December 11 1996.

But almost immediately after take off the two pilots noticed flames coming from the engine.

Eastern Daily Press: The existing substation at Necton for the Dudgeon offshore wind farm. It will have to treble in size for two new Vattenfall wind farms being built offshore, sparking protests in Necton. Photo: StatoilThe existing substation at Necton for the Dudgeon offshore wind farm. It will have to treble in size for two new Vattenfall wind farms being built offshore, sparking protests in Necton. Photo: Statoil (Image: Archant)

The pilots ejected over Narborough.

They became trapped in trees in their parachutes and were later rescued.

The plane carried on flying eastwards for nine miles before crashing in a field between Necton and Ivy Todd.

The headline in the EDP the next day was 'Our lucky day' as nobody was harmed and a school was near the crash site.

Eastern Daily Press: Vattenfall will need to build two new electrical substations at Necton. This is how a High Voltage Direct Current (HVDC) substation may look. It is higher than the High Voltage Alternating Current (HVAC) option. Image: VattenfallVattenfall will need to build two new electrical substations at Necton. This is how a High Voltage Direct Current (HVDC) substation may look. It is higher than the High Voltage Alternating Current (HVAC) option. Image: Vattenfall (Image: Vattenfall)

This newspaper reported the fighter jet missed rooftops by a few feet.

Eye-witnesses said they saw a fireball in the sky and heard a huge bang.

A 600 metre exclusion zone was put up around the site and the crash made a crate 20-feet wide.

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