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Title: 1993 general quality assessment (GQA) Cornwall area
Author: A. Gurney
Document Type: Monograph
The 1993 GQA classification has been assessed using sample results collected between 1 January 1991 and 31 December 1993. Every year a site is chosen to represent the water quality of each stretch. The annual sample results collected at these sites are then combined to produce a data set for each stretch, which is used for GQA classification. Stretches with the same 1993 site may therefore not have the same 1993" GQA classification, as the data sets for these stretches may contain samples from different sites for 1991 and/or 1992. The GQA chemical grade is defined by standards for the concentration of BOD, ammonia and dissolved oxygen as summarised in Table 1. The overall class for each stretch is determined by the lowest class of the three parameters.
Publisher: National Rivers Authority
Publication Date: 1994
Publication Place: Exeter
Subject Keywords: Pollutant loadAmmoniaDissolved oxygenWater qualityRivers
Geographic Keywords: CornwallRoadford ReservoirTamarSeaton (Devon)DevonLooe (river, Cornwall)
Extent: 34
Total file downloads: 33

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