This report covers data collection during periods of plant operation and the subsequent processing carried out of that data. A brief outline of both operational and subsequent processing is given, followed by an overview of the hardware used and software packages available. The configuration of the main Data Acquisition System package is described in some detail. The bulk data handling carried out after completion of plant operation is described and, where this is prepared by the project, source codings are given. The tasks performed on a routine basis using small micro-computers are described and the appropriate program listings provided. In conclusion, suggestions are made on how these tasks could have been better performed, had the full data processing requirements been known initially. 16 figs., 1 tab.