Sixty households beside the historic waste site in Surrey, which has been at the centre of a bitter three-year legal battle surrounding Zane Gbangbola’s death, have been sent a letter warning them not “restrict airflow” in their homes.
It contradicts repeated denials, by a string of public authorities, that the site is hazardous or even exists.
It raises deeply troubling questions over the 1,655 historic landfills across the UK thought to contain dangerous materials.
Father Kye Gbangbola said: “This is a backdoor means of informing the public there is a risk but without accepting responsibility for what happened to Zane.”
Zane suffered a cardiac arrest in the family's Chertsey home beside the River Thames, on Saturday, 8 February, 2014, during flooding which deluged the South East.
Last September a coroner ruled he died from carbon monoxide toxicity after inhaling fumes from the family’s petrol pump hired to drive flood water out from their basement.
But his parents consistently argue – backed up by an impressive level of scientific and medical records – that he was killed by hydrogen cyanide (HCN) fumes carried by flood water from the neighbouring historic Lavenders landfill at Abbeyfields Park.
Over Christmas, Surrey council sent letters to the 60 homes, which are all within 250 metres the Chertsey site at Abbeyfields, also known as Lavenders, telling them never to use self-sealing airbricks.
The airbricks, which can trap harmful gasses inside a home, were given out as part of the 2014 ‘repair and renewal grant’ for flood-affected households.
According to a Freedom of Information Act request, £46,000 was wasted on the the bricks and replacement will cost an extra £31,000.
The council said the bricks were unsuitable because the EA told it they “restrict airflow” and because it is important to “maintain a ventilated subfloor”.
The EA gave out the advice in June and a spokesman said the issue emerged in Spring 2015.
Fiona Dent, a Labour party Surrey county councillor candidate for the 2017 local elections, whose nearby Egham home was flooded that winter, questioned why this was not raised at Zane’s inquest.
“It begs the questions: why are they sending out this letter and is it because of the potential of poison gas all the way along the Thames?” said Ms Dent.
“There are so many factors that just don't add up in the handling of both Zane’s case and in the handling of this safety advice, that I have to ask myself: what information is being kept back from the general public and why?
“Both the Environment Agency and Surrey County Council definitely have more questions to answer about the safety of people living on floodplains near landfill.”
Environmental consultant of 25 years Paul Mobbs said: “The letter is saying the obvious; that if you live near any site that has the potential for gassing, you can’t create any pockets for it to build up to a toxic level.”
Mr Mobbs said there is no telling how “dangerous” the site is because no one has yet properly tested the soil.
“There is one simple way. You put a big auger in the soil about two to three metres down – you don’t just test the lake water – and send it to the laboratory,” said Mr Mobbs.
“They’ve never done it because I think they know what they’ll find.”
Workers were also pictured last November, in full protective gear, dismantling a bund over a nine-day period that had been built illegally on the site.
Mr Mobbs’ believes that if government claims the land is dangerous, the landowner Brett will either sue or abandon the plot, leaving a remediation bill he estimates at between £60m and £100m.
According to calculations by Dr Daren Gooddy of the British Geological Society (BGS), there are 21,027 historic landfills that date between 1890 and 1990.
An estimated 1,655 contain dangerous materials such as hazardous chemicals and asbestos, 1,264 are by the coast at risk of erosion, and an extra 2,964 are on flood plains.
“There are literally thousands of historic sites,” said environmental geochemist Kate Spencer, from the Queen Mary University of London, whose 2016 report said there was “serious” potential for contamination from the old coastal sites.
“There are too many sites to remediate all of them and many pose no immediate risk, therefore we need to develop a strategy to prioritise those that present the greatest risk so that we can focus remediation efforts.
“We need more information to understand the potential risks to human health of re-exposing solid waste to the environment that has been previously buried.”
An EA spokesman said the Christmas letters were given out because of planning regulations by local authority Spelthorne Borough Council and denied any suggestion the site was toxic.
It also said the lake on the site posed no health risks and that there were no danger to other homes.
“The old landfill site in Chertsey known as Lavenders is currently a lake. The lake shows no environmental signs for concern. It is home to a healthy fish population. It has been tested and the results shared with the coroner. This is covered in his verdict,” he said.
The spokesman admitted the soil on the site, surrounding the lake, has never been tested because the EA was not told to do so by the coroner.
“If you have HAZMAT, fire crews and Public Health England saying there is a detection of hydrogen cyanide at our house, a weapon of mass destruction, to not test the landfill is extraordinary and an affront to the rule of law,” said Zane's mother, Ms Lawler.
“Recently we have seen Hillsborough criminal charges and the Grenfell Tower tragedy with authorities allegidly doing and saying whatever necessary to protect reputations and misdirect the wider public that those victims complaining of injustice are not worthy of being listened to.”
"We are consumed with the pain of deep sorrow from the death of our precious Zane, still traumatised and literally paralysed from the catastrophic events of that fateful night but we will never allow the truth to be buried, we will continue to fight for the truth, as the truth always comes out in the end."
A Spelthorne council spokesman refused to answer questions, and repeatedly referred (the Mail on Sunday) to the coroner’s ruling which it said addressed “inaccurate press coverage”.
Regarding the letter, the spokesman said: “We are aware that the EA were planning to replace some airbricks which had been fitted to properties at risk of flooding because of their proximity to landfill.
“We have not as yet been able to establish that this was related to any planning regulations.”
Brett failed to respond.
Zane's parents have co-signed the Hillsborough Bill, introduced to parliament last month by the Labour Party's former shadow home secretary Andy Burnham, and the Green Party along with many others are campaigning for the family to be granted an independent panel inquiry into their case.
With thanks to Peter Walker