Catalogue description Welsh Office: Environment Division: Contaminated Land Survey Database

Hardware: IBM-compatible Amstrad PC. The Cardbox system was subsequently (July 1998) run on an IBM PS/2 Model 55SX.

Operating System: IBM DOS Version 4.00 (as at July 1998).

Application Software: Data from the original 1983/84 survey was held on a system at Liverpool University and accessed on-site via IBM terminals using a program called 'Extract'. The data from the 1987/88 update was entered on Cardbox Plus. Cardbox Plus is an information management system which handles records like a stack of index cards.

User Interface: Data gathered in the 1987/88 update was entered on a Cardbox Plus system (see Application software), and was held by the Welsh Office's Environment Division in that format. The features of Cardbox Plus therefore determined how the data could be accessed and used by the Welsh Office. Cardbox Plus is not, and does not purport to be, a relational database management system. Input is 'free-format' in that text or numbers can be entered into any field, and the only validation on input is that the number of characters (specified for each field when the input screen was created) is not exceeded. Any word, number or date can be indexed to allow retrieval. Each Cardbox field can operate in one of four indexing modes: None (nothing is indexed); All (everything is indexed); Manual - only the words marked by the user are indexed (a word is indexed or un-indexed by hitting the TAB key; marked words are highlighted); and Automatic - every 'word' is indexed unless marked by the user.

Logical structure and schema: Data is held in a single file in the dataset for the 1987/88 update of the Survey of Contaminated Land in Wales. Further details of the fields in this file are provided in the catalogue of the dataset.

No new data was added to the Contaminated Land database after the 1987/88 update was carried out. It is not known whether this data would be overwritten in any future update of the database.

How data was originally captured and validated: the original 1983/84 survey, site data was sorted, marked on a master map, and screened to assemble a list of contaminated sites. Site records were entered into a file or computer database and priority ratings in terms of hazard or need for remedial work were allocated. The 1987/88 update checked the findings of the original survey in each district of Wales and noted any changes, adding new sites where necessary. This entailed consultation with each district council, followed by visits to each district to check on sites for which information seemed questionable. The procedure did not include automatic visits to all sites; the majority of sites, which were well documented and about which no doubt existed, were not visited. No detailed site investigations were carried out specifically for the survey. The update also attempted to point out the main areas where a large number of contaminated sites existed.

The survey methodology followed essentially the same method as the original survey. Site identification was divided into three categories as follows:

• 1. Those sites originating in the expansion of heavy industry between 1850 and 1950, since abandoned.
• 2. Refuse and industrial waste disposal sites.
• 3. Industrial sites which had been abandoned after 1950.

Category 1 sites were typically located using large scale maps, and category 2 sites through local authority sources and some use of aerial photographs. Category 3 sites used these methods, plus other available sources such as the Welsh Office Derelict Land Survey and some archive material such as directories and site plans.

The Survey of Contaminated Land in Wales was carried out by the Environmental Advisory Unit of the University of Liverpool, on behalf of the former Welsh Office and the Welsh Development Agency.

In 1982 the Welsh Office and the Welsh Development Agency jointly funded a research project by the Environmental Advisory Unit (EAU) of the University of Liverpool to develop a methodology for locating and recording contaminated land in Wales. A selection of the techniques recommended in the two earlier studies was applied in a pilot study; carried out by the EAU in Clwyd in 1982. The experience gained in this pilot study enabled the EAU to conduct a survey of contaminated land in Wales in 1983/84. Data gathered in the survey was entered in a database and was used to prepare a report which was issued in March 1984. The report listed all contaminated sites not in active use for industry or housing.

In 1987 the EAU was commissioned by the Welsh Office to undertake an update of the data resulting from the original survey. This update was conducted in 1987/88 and led to a report which was issued in August 1988. It had been intended that sites would be removed from the updated database where contamination had been removed or the site had been redeveloped and was in active use. According to the 1988 report, no sites were in fact removed from the database. Sites which had been partially redeveloped were retained with a reduced size or hazard rating for the remaining contaminated area. Sites added to the database consisted of newly vacated industrial premises, waste disposal sites identified by the relevant authorities and previously unrecorded sites which had come to be regarded as significant since the 1983/84 survey.

The aim of the original survey and the 1987/88 update was to help to identify contaminated sites before they were redeveloped, thereby avoiding the financial costs and risks to which developers and eventual occupiers of the site might be exposed. Guidelines issued by the Welsh Office and the Department of the Environment required planning authorities to take account of contaminants and impose appropriate conditions on developers, to ensure that future users and occupiers of contaminated sites were not exposed to hazards. The data derived from the 1987/88 update, like that from the original survey, provided planning authorities with the information to discharge this responsibility.

Data gathered in the 1987/88 update was used by the Welsh Office to answer enquires from universities and colleges, local authorities and the general public. However, the Welsh Office regarded the data as being out of date for certain purposes, such as ascertaining the value of land. Within the Welsh Office the responsibility for monitoring contaminated land rested (in 1998) with the Land Quality Section of the Environment Division of the Transport, Planning and Environment Group.