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.