Putting decommissioning on the map

Reactors and robots, paratroopers and planes - the Harwell site in Oxfordshire has seen it all. Soon to be hailed as an international business centre, the area is currently undergoing a thorough liability review. In the second part of the UK Atomic Energy Authority (UKAEA) series, Beverly La Ferla learns how a new computer mapping tool has facilitated a site assessment for chemical and nuclear ground contamination.

Once a pioneering centre for nuclear energy, and before that an RAF base which

supplied troops for D-Day, Harwell currently houses the headquarters of the

UKAEA. The centre has been charged with decommissioning the on-site nuclear

reactors and other facilities used for the UK’s nuclear research and development

programme in a safe and environmentally sensitive manner. The objective: to

restore the site for use as an international business centre.

Three years ago, the Site Survey Project was born, headed by Clark Colyer,

senior project manager at UKAEA. He put together a team that could cover both

the historical records aspect and the assessments of land quality, and combine

these to provide a comprehensive report on the possible presence of contaminants

throughout the site.

Database issues soon took priority: the project had to incorporate a quality-controlled,

auditable procedure for collecting, collating, retrieving and interpreting the

environmental survey results and cross referencing these with the history of

the buildings and the site. UKAEA commissioned ESiT Ltd (Effective Solutions

with Information Technology) to develop a data management system called IMAGES

(Information Management And Geographical Evaluation System), which comprised

a number of database modules and desktop tools.

Seamless interfacing

The database modules were created to record a range of environmental data types,

such as groundwater quality monitoring data, ground investigation data, sample

analysis results, radiation survey data, and building history in the form of

documents and images. The databases that contain information with a geographic

component were designed to interface seamlessly with Arcview GIS (Geographic

Information Systems), a computer system which enables a pictorial representation

of the data to be displayed.

UKAEA were delighted with this tool and the project started to gather pace

after February 1999. Malcolm Crook, environmental records manager, was put in

charge of the historical side with Grant Baldwin as project operator feeding

survey information to Sandra Owsett, GIS operator. This three-man team, headed

by Clark Colyer, started to put together an assessment of potential liabilities

on the site – a task which they have almost completed.

Malcolm’s extensive experience in records management made him the ideal person

for his job. “I delve into the archives for records that gives me an idea

of what the buildings or areas of land were used for and extract information

on potential areas of contamination,” he says enthusiastically, “The

history of the site goes back to when it was an operational RAF base in 1937,

complete with dispersed runways and practice bombing areas.”

Bought for just £11,000 by the Ministry of Supply (now the Ministry of

Defence), the site was an operational training unit for bomber command. During

the second World War, it played a vital part in sending paratroopers and light

forces to Normandy on D-Day, an accomplishment it is still proud of today.

“The buildings, originally built for the RAF, have been converted through

the years for other uses,” Malcolm explains, “For example, one RAF

barracks block was turned into laboratories in Harwell’s nuclear physics heyday

and is now office accommodation.”

A total of 627 records on all the buildings ever constructed at Harwell – including

general purpose huts, air-raid shelters and toilet blocks – contributed to the

historical side of the database, and this information was then used by Grant

to select areas that needed to be sampled for possible contamination.

A number of surveys have been done on the site. Geo-physical techniques, which

measure the change in electrical conductivity of the soil, have uncovered objects

like bullet cartridges and flares, which have been buried for decades. The radiation

data was gathered using a Global Positioning System (GPS) to pinpoint areas

of interest and chemical surveys have involved digging ‘trial pits’ down to

three metres to collect samples for laboratory testing for contaminants. The

pits are also given the once over with radio and metal detectors, a CAT scanner,

and a photo-ionisation detector which determines the levels of volatile organic

carbons (VOCs) present.

These results, complete with location tags, are then fed back into the database

by Sandra. Clark Colyer explains: “Because the historical records and sampling

data are held electronically in a way that’s retrievable and geographically

traceable, we can combine them to make maps showing areas of potential liability.

It would be nearly impossible without the program – we’d have to use at least

one aircraft hangar to store all the files that we’ve generated in the last

three years!”

After three years of extensive searching, the surveys have brought up nothing

unusual, leaving Harwell on course for unanimous approval as an international

business centre. The mapping team is two-thirds the way through the Site Survey

Project and hopes to finish it next year. After that?

Well, there are plenty more nuclear sites being decommissioned in the UK and

many others who could apply the techniques the Harwell team have pioneered to

return land that has been used for industrial purposes to green field status.

Action inspires action. Stay ahead of the curve with sustainability and energy newsletters from edie