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Canvey Island (Industrial Installations)

Volume 984: debated on Thursday 8 May 1980

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Motion made, and Question proposed, That this House do now adjourn.—[ Mr. Boscawen]

11.5 pm

I make no apology for drawing attention once again to the dangers that my 34,000 constituents in Canvey Island face from the largest concentration of liquefied gas, chemical and oil storage installations in the country. No one who has read the Health and Safety Executive's report on the subject, which was published in June 1978, can be left in any doubt about the unique web of risk in which my constituents are enmeshed. One cannot fail to grasp not only that each specific risk is dangerous enough in itself but that it is made more so by the proximity to others.

Indeed, after all the improvements in safety proposed by the Health and Safety Executive in its report have been implemented—and that will take some years—the level of risk will still be unacceptable. The report estimates that one-third of the total risk comes from one installation—the British Gas methane terminal. It imports 12,000 tonnes of liquefied natural gas each week. It is stored in four huge, below-ground earth pits and six above-ground insulated tanks which are far too close to people's homes for health or comfort. The terminal is licensed to hold 110,000 tonnes of LNG, although at the end of last year the amount involved was about 55,000 tonnes.

When natural gas is cooled to the immensely cold temperature of minus 162 degrees centigrade, its volume is reduced 600 times. Put another way, one LNG tank contains as much energy as 600 similar size tanks filled with normal natural gas. Liquefaction is certainly a convenient and economical way of transporting and storing natural gas, but because of the immense concentration of energy each weekly tanker arriving at Canvey is equal in energy terms to six Nagasaki-type atomic bombs—and that is attended by grave danger.

If an LNG tanker became involved in a serious collision in the Thames estuary while discharging its cargo at the terminal jetty, or if there were a sudden rupture of one of the above-ground storage tanks leading to a major spillage, the liquid released would quickly vaporise, mix with air and form a cloud which would become highly flammable. As the cloud would be heavier than air, it would cling to the ground. Since our prevailing winds are south-westerly, it would sweep towards a densely populated area where sources of ignition abound.

As the Comptroller-General reported to the United States Congress in July 1978, following an exhaustive inquiry into the safety of liquefied gases,
" a major spill in a densely populated area, whether by accident, natural forces, or sabotage, could be catastrophic."
The HSE knows that that can happen at Canvey. It has admitted that once a major spillage takes place nothing can be done to prevent the formation of a gas cloud and its inevitable ignition.

Oddly enough, in spite of our experience at Canvey in the last 15 years—experience of the collision of ships with liquefied gas cargoes, ships colliding with jetties, rupturing pipelines, and accidents at the methane terminal—only in the last few days have we learnt that experiments are to take place to establish the behaviour of large quantities of liquefied gas when released accidentally. Shell has announced a series of tests on Maplin sands during the summer. One object is to ascertain whether, on ignition, a gas cloud will explode or merely burn.

Shell has a commercial interest in the matter. It is involved in the development of a large gas-processing plant and tanker terminal at Moss Morran in Fife. It is anxious to reassure objectors to its plans. The interest of my constituents is very different. It matters not at all to people threatened with a disaster whether they will be blown to smithereens or merely incinerated. What they are entitled to know, and what I hope they will be told, is the justification for allowing such a major hazard as that at Canvey to continue in operation so dangerously close to their homes and to the schools that their children attend.

I must ask my hon. and learned Friend the Minister whether it is intended to monitor the Shell tests independently, by the HSE. If not, why not? Are the results to be made known to the local authorities and to the general public? If so, how soon after the tests are completed? I agree that anything that adds to our knowledge of the behaviour of liquefied gases is to be welcomed.

The report to the United States Congress on the safety of liquefied gases which I have already quoted said only two years ago:
" Risk assessment studies have not reached a stage where their conclusions can be relied on. Until they do, regulators will have to attempt to make timely, prudent, siting and other critical judgments with the realisation that many important safety questions cannot yet be answered with confidence."
That is still the position in this country today. It is no wonder that the report concluded that future facilities for storing large quantities of these gases should be built in remote areas.

I emphasise that the fact that the Shell tests are now to take place shows just how neglected has been the whole question of handling LNG close to populated areas. There is, however, one ray of hope. I have the impression that the Government are now alert to the problem. Indeed, in recent months Ministers—including my hon. and learned Friend—have shown more genuine interest in the subject than have any of their predecessors. I am glad to put it on record that my right hon. Friend the Secretary of State for Employment invited me to bring my own scientific advisers to a meeting with him, my hon. and learned Friend and the HSE to discuss the whole question of Canvey safety. We met on 3 December. It seems that our arguments, especially about the risks associated with LNG, impressed my right hon. Friend because he agreed to our discussions continuing at official level.

For the first time ever, the Government acknowledge that we face a serious and worrying problem and seem anxious to find a genuine solution. Moreover, British Gas itself seems to be waking up to the fact that its activities on Canvey have to be reduced. Early in March it announced that it was preparing to decommission the four in-ground earthen storage pits. That was good news.

Then, suddenly, events took a new and alarming turn. A constituent who was an electrical engineer at the terminal from September 1978 until August last year came to see me with an astonishing story. He told me that on taking up his appointment he found that there had been no qualified electrical engineer at the terminal for at least nine to ten months. There were no proper handover, very few technical documents and no record at all of electrical interconnections. His preliminary investigation revealed serious defects in electrical equipment and safety systems. Standby electricity generators were not working. Most serious of all, he found evidence suggesting that the internal safety and alarm systems in the six above-ground tanks were defective. He reported all that to the terminal management.

I should perhaps explain that these safety and alarm systems would give warning of overfilling of the tanks with liquefied gas, which might cause tank rupture, spillage and the formation of the dreaded gas cloud. Hon. Members will readily appreciate that failure in any part of a multiple alarm and safety system is serious because the strength of the whole is that of the weakest link. Even the most junior safety officer employed in industry knows that.

It was not until last summer that my informant was able to inspect these systems. In one tank which had been emptied for the first time in 10 years, he found that his suspicions were justified. One system, a high-level auditory alarm, was defective and would not have worked. He was unable to inspect the second system, a high-level trip, which would have shut off the inflow of gas in the event of the tank being overfilled. British Gas says that this was checked by another member of its staff. Despite my informant's doubts as to safety, the tank was refilled with gas.

As all these tanks are inspected internally only once every 10 years, there were grounds for thinking, so my informant told me, that the back-up safety systems were defective in all of them. I have seen his report to the management, and there is little doubt that chances were taken with safety. He resigned shortly afterwards.

My informant reported the matter to the HSE before coming to see me. Inspectors swooped on the terminal on 6 February and confirmed that the high-level alarms were not working and that the high-level trips, while said to be operable, were unreliable. I must pay a tribute to the HSE. Once it had the information, it moved with the most commendable speed. It set out its requirements to British Gas in writing. The director-general told me later:
" From the commencement of the investigation, intense pressure was being applied to British Gas".
By 6 March, the HSE was of the opinion that it had achieved a substantial risk reduction. A new alarm system had been installed. A fully qualified electrical engineer from a professional agency was engaged on 17 March. On 25 April the HSE served three enforcement notices on this great national monopoly. The first was to take immediate effect and required that the levels of liquid in the above-ground tanks should be reduced. The second requires that an additional system should be installed by 31 July. The third requires additional safety devices, independent of others in service, of a standard of reliability recommended in the HSE report to be installed by 1 May 1981.

I must tell my hon. and learned Friend the Minister that I am uneasy about that third requirement. That means that we are obliged to wait on trust and that recommendations made by the HSE, originally in June 1978, will not be implemented until three years later. I say that that is far too long. If British Gas cannot meet that requirement now or by the summer, the terminal should be closed down.

I shall give my reasons for saying that. Let us consider for a moment what these developments mean. Clearly, there has been an appalling neglect of elementary safety precautions in a plant which the HSE rates as a " major hazard ". It will be recalled that the court of inquiry into the Flixborough disaster found that at that time an inadequate bypass system was installed to keep the plant in production. Just at the time when that was done—and I quote from the report:
" The key post of Works Engineer was vacant and none of the senior personnel of the company, who were chemical engineers, were capable of recognising the existence of what is in essence a simple engineering problem let alone solving it. "
There was a direct connection between this absence of professional expertise and the events which led to the complete destruction of the nypro plant and the deaths of 28 people. In my opinion, it was disgraceful that a major gas installation, where the back-up safety systems are electrically activated and where the numbers of people at risk beyond the plant are far greater than at Flixborough, should not have had any qualified electrical engineer in post on the site before September 1978 or for some months after August 1979. It was only after the HSE investigation had established defects in the electrically-operated safety systems that steps were taken to appoint such a suitable qualified man.

There is a savage irony in all this. When the HSE, acting with the best of intentions, advised the Castle Point district council in the autumn of 1978 not to allow any new planning permissions within a radius of 1 kilometre of the terminal—thus serving notice on 8,000 people that they lived in an area where there was some danger—the management of the terminal was taking chances with safety within the plant itself. It had learnt nothing at all from the Flixborough disaster.

Indeed, British Gas at the highest level has learnt nothing either, for when the facts about the terminal were out in the open its spokesman told millions of viewers, in a Thames Television programme on 10 April, that at no time had fewer than three types of alarm operated satisfactorily on each tank. That was a lie, and British Gas knew that it was a lie because the HSE had discovered otherwise two months earlier.

For full measure, the same spokesman said that over a period of 15 years no incident involving risk to safety had taken place at the terminal. That too, was a lie. I have since reminded the chairman of British Gas of a number of incidents any one of which might have triggered off a disaster.

I mention this because the improvements which have been enforced by the HSE have to be seen against a background of incompetence at the local level, cover-up at the national level and deliberate lies and distortions over a matter which touches on the safety of a large community. There is no confidence in my constituency of Essex, South-East that British Gas should be allowed to continue operating a major hazard installation so close to a large residential population. Already the local authority has demanded that the terminal be closed down, and a very heavy responsibility rests upon those who say otherwise.

My hon. and learned Friend will doubtless remind me of the decision already taken to decommission the massive in-ground storage of LNG at Canvey—an operation which will be fraught with some difficulty because the surrounding soil of the four huge earthen pits is saturated with gas.

But, as matters stand, the chairman of British Gas tells me that he has no intention of decommissioning the above-ground tanks. I submit to my hon. and learned Friend that the issue is no longer one which can safely be left to British Gas to decide. It is utterly wrong to ask my constituents to accept the present level of risk or wait a further year for one of the three enforcement notices to be fully implemented.

I beg my hon. and learned Friend to indicate, at the very least, that the Government will consider whether this major hazard should be permitted to continue its operation at Canvey. I am asking him to give hope to my constituents that the dangers to which they have been exposed for far too long will be removed as quickly as possible.

11.23 pm

I am glad that my hon. Friend the Member for Essex, South-East (Sir B. Braine) has been successful in his application to discuss this subject on the motion for the Adjournment of the House. It is a matter of extreme importance to his constituents whose interests on this, and indeed on all other matters, he has so long and so faithfully represented. It is also a matter which concerns the constituents of my hon. Friend the Member for Maldon (Mr. Wakeham), who is in his place tonight. Of course it is a matter of the greatest concern for the Government, who have the overall responsibility for operating and enforcing the Health and Safety at Work etc. Act through the agency of the Health and Safety Commission and Executive.

I am grateful to my hon. Friend for what he has said about the scrutiny that the Government are giving to the conclusions drawn in the Canvey report of the HSE in 1978 in consultation with his own scientific advisers. I am also grateful for the tribute that he has generously paid to the HSE for the swift way in which it took action this year when new information, to which he has referred, became available regarding the reliability of the safety devices fitted to the six above-ground tanks for the storage of liquid natural gas operated by the British Gas Corporation at Canvey.

My hon. Friend has been kind enough to keep me informed of and closely acquainted with the representations that he has made both to the chairman of the British Gas Corporation and to the director general of the HSE in the light of this important new information. As my hon. Friend has told the House, it came to light from a former employee—an electrical engineer employed at the site—and I am grateful for it.

It was made known to the area director of the HSE, Mr. Peter Yeomans, on 1 February of this year that there were serious deficiencies in the systems designed to guard against over-filling of the above-ground tanks, in particular in electrical equipment and electrically-activated safety systems. In consequence, two principal inspectors of factories visited the terminal at once.

I should mention at this stage that because over-filling a tank with liquid natural gas can lead to an escape of that gas, with the possible rupture of the tank and the formation of what must be a highly dangerous cloud of gas, each tank is fitted with four separate devices designed to indicate in different ways whether over-filling has occurred. That is a measure of the precautions that are needed.

However, the design safeguards consist of, first, one high level alarm: secondly, a high level trip, which cuts off the inflow of the gas if the level get too high; thirdly, a tell-tale escape valve; and, fourthly, a level indicator sited in the control room. Of these, only the first two can properly be classed as alarms. On inspection, it was found that, among other deficiencies, on five of the six tanks the high level alarm was not operating. There was no indication of how long that state of affairs had pertained.

As regards the high level trips, which cut off the inflow of gas, these, though not known to have failed on any occasion, cannot, I am advised, be tested short of opening up a tank, or deliberately over-filling a tank—which is a highly undesirable procedure. They are considered to be of unreliable design themselves.

Furthermore, on inspection of British Gas's internal records, it was apparent that the regular internal examination of one of these tanks was six months overdue. The HSE immediately sought assurances from British Gas that these and other matters would be rectified. It also asked the date of the expected appointment of a resident electrical engineer. None had been resident for the previous five months.. By 6 March new high level alarms had been fitted on all six tanks, replacing the defective alarms.

Discussions with British Gas on further precautions considered by the HSE to be necessary to guard against over-filling of the tanks continued, but British Gas failed to give unqualified agreement to these requirements, and accordingly, as my hon. Friend has mentioned, three enforcement notices were served upon the corporation on 25 April.

I think that it is worth mentioning the details of those. The first is an immediate prohibition notice, with which British Gas has complied. It requires that during filling operations safety margins are increased by setting lower maximum levels for filling and by more frequent level readings. The second notice, which is a deferred prohibition notice, requires that by 31 July this year British Gas must install a continuous recorder as part of its control room monitoring equipment together with additional high level, high reliability alarms which can be fitted or removed without taking any of the vessels out of service.

The third notice, an improvement notice, requires, as my hon. Friend has mentioned, that by 1 May next year independently operated level indicators should be installed on each tank with each system operated on a different physical principle, with at least one capable of being tested and maintained without the need for the tank to be taken out of service. In addition, an automatic high level alarm with automatic cut-off for the tank feeds should be installed, independent of the two-level measurement system and capable of frequent proof testing.

British Gas has indicated that it does not propose to appeal against these orders, either as to their substance or as to the time limits for complying with the last two. These orders provide for important additional safeguards. In relation to the point that my hon. Friend makes about the delay in compliance with the third until May of next year, I would simply say that the first prohibition order for immediate compliance makes significant reductions in the maximum levels for filling and adds very considerably to the frequency of the required tests for checking the level as filling takes place. These are additional safeguards of a significant and important nature which have to be complied with straight away.

I have noted the trenchant criticisms that my hon. Friend has made about the management of the methane terminal. Criticisms of management control were expressed to British Gas on the occasion of his visit by the area director of the Health and Safety Executive in April. Changes in management have been instituted by British Gas. However, I am advised that it cannot be right to claim, as a representative of British Gas did, I understand, on ITV, that at no time have fewer than three types of alarm operated satisfactorily on each tank. Accordingly, I give an assurance to my hon. Friend that the executive itself will be monitoring closely both management control and the work required by the enforcement notices, and additionally all other aspects of safety at the methane terminal.

The information that came to light has been of great value. Taken together with the improvements already required by the Canvey report, most of which have been carried out or commenced, the further improvements at the LNG tanks that are specified in the improvement notices will, in the view of the executive, mean that the chances of the accidental formation of a gas cloud will be very remote.

The recommendations of the Canvey report took account of the likely behaviour of such a methane gas cloud if it came to be formed. The executive has some knowledge of what may happen in the unlikely event of a large release of methane. I concede that its knowledge is far from complete. It is for that reason that the report was cast deliberately on a pessimistic view. Accordingly, we welcome the series of tests that Shell proposes to carry out on Maplin sands this summer.

The executive will be represented at the tests. I give a further assurance to my hon. Friend that its own observations and conclusions drawn during the tests will be made available to my hon. Friend and to all other interested parties at the earliest opportunity.

My hon. Friend asks the executive and the Government to go further and to close down the methane terminal at least until there has been compliance with the orders. I can assure my hon. Friend that I shall give the most careful consideration to his remarks. I am aware of the proper anxieties of his constituents, as is the executive. The readiness of the executive to protect his constituents' interests in accordance with the health and safety at work legislation has been demonstrated by the speed with which it has moved. However, it is not its duty under that legislation to ensure that no possible risk exists. Its duty is to judge when enough has been done to minimise the chances of a major incident which would cause injury. It is a heavy responsibility, but it is one that must be discharged.

The advice that the executive gives the Government is that enough will have been done, in its judgment, provided that the restrictions and the improvements specified in the orders that it has served are implemented. It will closely monitor that implementation. If at any time the executive believes that a temporary or a permanent shutdown of the above-ground LNG tanks, or the methane terminal as a whole, is necessary in all the circumstances, it will require it. I hope that what I have said in response to my hon. Friend's valuable speech, which was based on the valuable information made available to him and to the executive, will serve to reassure both him and his constituents.

Question put and agreed to.

Adjourned accordingly at twenty-five minutes to Twelve o'clock.