The south Oxfordshire countryside narrowly missed being showered with radioactive fallout, but 99.9% of the local population don't know anything about it.

What is Harwell and where is it?

Harwell is a village in south Oxfordshire, England.

51° 35.87' N, 1° 17.63' W

SU: 48900 89043 (OS grid)

The village is home to the nearby Rutherford Appleton Laboratories (RAL), a civilian scientific research institution (rl.ac.uk). RAL carries out research in particle physics amongst other things. However, the RAL site is also home to the National Chemical Emergency Centre and a more sinister organisation, the UK Atomic Energy Authority (UKAEA). The AEA facility is known as Harwell Labs, 

 The original owners of the site were the AEA. Harwell was used to develop the first British nuclear weapons, under the control of Ministry of Defence after World War II. However, as far as the public are concerned, all weapons grade material and research is housed at the Atomic Weapons Establishment (AWE) at Aldermaston in Berkshire some 30 miles away. Today, the public are only aware of the RAL work on the Harwell site.

The UKAEA facilities at Harwell labs are used for research into decommissioning nuclear power plants. Work on weapons, or weapon components, though suspected by many, has been vigorously denied by the authorities.

51° 34.93' N, 1° 18.50' W

SU: 47912 87326 (OS grid)

So what happened?

On the afternoon of Thursday September 9, 1999, an experiment, involving a number of radioactive elements, produced an unexpected and highly explosive by-product called Silver Picrate. This chemical escaped into free-air within Section 220 of the Harwell Labs. The alarm was raised and the building sealed, with Harwell Labs employees being evacuated at around 17:00 (5:00 pm).

Silver Picrate, UN 1347, though not technically an explosive, if allowed to dry out (>30% water) becomes extremely unstable. In this situation, there is a high risk of detonation if the chemical is subjected to shock or friction. A US Department of Transport guide book suggests that in the event of a spillage of Silver Picrate, an area of 800m around the spillage should be evacuated.

There was an extremely high risk of the Silver Picrate exploding and blowing the roof off the building. Had this happened the radioactive elements could have become airborne, with the fallout showering the surrounding area.

Experts from the UKAEA research and experimental reactor facility at Dounreay, near Thurso in Scotland, were flown to Harwell in the dead of night. Their job was to avert disaster and make the situation safe. Meanwhile at Harwell, Army bomb disposal teams arrived on the scene, as did a number of local fire appliances, supplementing the on-site fire unit.

From the site, news of the situation was passed up through the UKAEA chain of command. The situation was so serious, with such a high risk to public health, that advice was sought from Whitehall, location of the Ministry of Defence.

At Whitehall, the decision was made to keep a news-blackout on the situation at Harwell. But not before at least one news broadcast, an early morning (Friday 10th) Central TV local news transmission, revealed that something was happening at the site. The report gave no details, it simply mentioned that something unusual was occurring there. The next Central News broadcast carried no information at all on Harwell, nor was any information available on the national or local teletext (a text service carried on UK television channels).

Later on Friday morning, local BBC radio, Thames Valley FM, announced that Harwell children's school was closed until further notice, but added that the authorities would not say why. This story was carried on a number of subsequent broadcasts, still with no further detail.

A number of local residents contacted Oxfordshire radio station, Fox FM, and mentioned that they had seen the bomb disposal teams and a large number of fire units going to the Harwell site. The authorities were still telling them nothing. Fox FM carried the story that something was definitely up, in an attempt to get some explanation, as given the nature of the work carried out at Harwell, this was clearly in the public interest.

To a degree this tactic worked. By Friday evening, the story had made national television news, and the UKAEA had made a press release. The news story claimed that work involving the recycling of domestic smoke detectors, and the radioactive element Americium, had gone slightly wrong, resulting in a small risk of fire at the site. They stressed that there was no danger to public safety. NOT TRUE.

A source, who was closely involved, believes that the public were put at extreme risk by the cover-up and has offered a near full account of what really happened. This source has confirmed that the situation was far more serious than the public were led to believe. The scientists and management at the site believed that an explosion would be difficult to avoid.

The Army explosive ordnance disposal (EOD) teams did not know the exact nature of the explosive substance and were powerless to counteract it. Fire crews, wearing full Nuclear/Biological/Chemical protection, whose job was to rescue the EOD team in the event of an explosion, stood by, less than 40 yards from the lab.

This source has told me that there was no Americium present at the time and that the smoke detector recycling story was totally untrue. However, other radioactive elements, such as Plutonium, was at risk of being blown up and scattered over the surrounding area.

but the source would confirm regular shipments of cargo between Harwell and AWE Aldermaston, amongst other military bases, with regular convoys of trucks and armed escorts using the A34 dual-carriageway. The source also confirmed that the initial experiment which had caused the problem, was related to weapons research.

Over 24-hours after the first alarm was raised, the experts from Dounreay along with local site staff, decided that their best chance at containing the situation was to neutralise the Silver Pectrate with acid. The Army EOD team were tasked with this assignment, but without a guarantee from the boffins that it would actually work.

Even with a less than 100% chance of success, the attempt to neutralise the explosive went ahead, thankfully with success. Crews from the Army EOD unit, and Oxfordshire Fire Service stood down and the situation returned to normal.

Di McDonald
Network Information Project
30 Westwood Road
Southampton
SO17 1DN
Britain
Tel/Fax: +44 - (0)23-80554434
e-mail: nipdimac@ gn.apc.or