Today's debate is not just about the future of Heathrow airport—whether it should get a third runway or whether we should introduce mixed mode—because we are talking about a judgment that will have a real and profound consequence for millions of Londoners. On Ministers' judgment will depend Londoners' day-to-day quality of life and, for some, even their health. I believe that people have a right to expect a reasonable quality of life, and that it is the Government's duty to respect that right and to protect public health.

The Government have given the House the fantastical assurance that adding an airport the size of Gatwick on to Heathrow will somehow make it less noisy and polluting. Ministers assure us that Heathrow is a hub and that London's economy will be irrevocably damaged and threatened without expansion. However, neither case has been made, and I believe that Ministers are about to take a deeply reckless decision for whose consequences they will never be held personally accountable.

Right at the beginning, the Government set important tests in the White Paper on noise and, in particular, on air quality. They assured people that they would "bear down" on noise and meet EU air pollution limits but, as we have heard, on air pollution the simple fact is that the UK is already set to breach the EU's 2010 mandatory limits on NOx levels, and that is even before any extra flights are added.

This afternoon, the Secretary of State admitted that our country will have to apply for a three or five-year derogation when it comes to meeting the EU pollution limits. How on earth, then, can the Government consider expanding Heathrow, given that that would mean an even greater rise in NOx emissions? It simply defies common sense—nearly as much as do the fantasy planes that my hon. Friend Mrs. Villiers mentioned and which have been included in some of the modelling that the Department for Transport claims proves that the proposal to expand Heathrow is possible.

Suspension of disbelief seems to be a common thread in the Government's attitude to the environmental case for expanding Heathrow. Let us take the subject of noise. The "Attitudes to Noise from Aviation Sources in England" report, compiled by experts and commissioned by the Government, which took six years to complete, said that people were more sensitive to noise now than in the past, which undermines the historical 57 dB limit used by the Government. The Government simply ignored that report.

My constituents will lose the half-day respite from aircraft noise that they so value. It is a crucial balance that all previous Governments have appreciated, yet the value of that half day does not feature anywhere in the economic case that the Government considered. All-day flights will make life in parts of London intolerable. Families and many other residents will simply want to leave.

The increased pollution will come not just from more planes in the sky, but from more cars on the road—a lot more cars. The expanded Heathrow will handle more than 60 million more passengers. That will mean around 40 million more people travelling to and from the airport, the majority of whom will be on the roads. As we have heard, that raises the nightmarish prospect of a serious deterioration in air quality, with major health implications, chaos on London's roads, and a gridlocked M4 that will grind to a halt more often than it already does. West London businesses and residents will face traffic hell. More planes, more cars, more pollution, more noise, a ruined quality of life—the environmental case for expansion simply does not stack up, and neither does the economic case.

As we have heard, the Government's own figures say that the net present value of the economic benefit is £5 billion. That includes £3 billion of extra air passenger duty, but we would be hard pressed to find anyone in finance who would say that tax should be counted as an economic benefit. Of course, if we included the full costs of the extra missing emissions for CO2, it would add an extra £5 billion cost, which would give the project a negative net present value; we all know that that is the reality.

Of course, all the so-called key evidence on adding capacity has been generated by the Department for Transport and BAA, which, unlike the rest of us, seems to have had unfettered access to the process. I am afraid that throughout that process, Ministers have not been frank with Members of this House or with the public about the information that they have looked at, on which they based their decisions. When I have tried to get information, whether through parliamentary questions or freedom of information requests, so that we could have a level playing field, at every stage I have met resistance. I have made freedom of information requests to which it has taken seven months to get an initial substantive response.

I was not the only one who was denied access to information. The Environment Agency was given no access to the detailed fact base that the Department for Transport had considered, so it is no wonder that the Environment Agency reached the chilling conclusion that there was a risk of increased morbidity and mortality if the Government went ahead with this reckless plan. Even the Department for Environment, Food and Rural Affairs was kept out of the loop when it came to the environment. The DFT compiled its own assessment of the risk of expansion, called the risk register, yet when I met the Secretary of State for Environment, Food and Rural Affairs, he was blissfully unaware of the existence of the document, let alone its contents.

The risk register states that the risk of pollution mitigation measures failing to meet air quality targets is high, but did Ministers make sure that DEFRA was aware of that? No. Did Ministers make sure that that "high risk" assessment, made back in October, got into the public consultation document, so that the public and businesses were aware of the risk assessment and the dangers? No. We should put that "high risk" assessment of pollution mitigation measures failing into context: the same team that assessed that risk as high also considered the risk of terminal 5 being a botch job, leading to reputational damage. I am sure that hon. Members will be amazed to hear that the risk attached to that was low. Of course, we all know what actually happened. The Government have shown that they did not foresee the risk of national disgrace and embarrassment in the case of terminal 5, yet we are about to walk headlong into another disgraceful risk. However, the outcomes could be far worse, and irreversible.

Concealing information and ignoring risks are all just part of the Government's consistently disingenuous attitude towards engaging with the public. That has pervaded all levels of the consultation process. At every stage of the modelling process, the Government's approach can best be described as "How can we fix the data to support our policy, and how can we twist the facts to get the result we want?"

Let me give the House a couple of examples of the discussion. On tackling air pollution, a DFT airmail on 28 March 2007 summarised the conclusions of a departmental meeting:

"Moving the source"— the pollution—

"away from the receptor is the most effective mitigation".

In other words, let us just have the pollution, but nowhere near places where it can be monitored.

A Heathrow project board meeting minute of 16 April 2007 noted:

"It was clear that moving NOx away from areas of exceedence was the most effective mitigation".

Translation: "Don't worry about reducing pollution—just move it away from measuring equipment, and spread it out a bit so that it doesn't show up too much." Most compellingly, an e-mail from the DFT on 10 August 2007 hit the nail on the head:

"It looked like a hunt for a model—any model" that would give a green light. That is self-explanatory. It was never a hunt for the reality of what Heathrow expansion would do to the environment—that never entered the Government's thinking—but a hunt for a model to get the right answer. One team member was reported as saying:

"It was a classic case of reverse engineering—it was awful."

I agree.