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Title: An investigation to determine the source of high levels of gamma-HCH in the Newlyn River during summer 1989
Author: R.P. Smith
Document Type: Monograph
Routine river quality sampling for pesticides in the Newlyn River on 30 August 1989 revealed 2600 ng/1 of gamma-HCH at Newlyn Bridge monitoring point. A special investigation involving four surveys isolated the source of gamma-HCH to a 3m stretch of river. It is considered that a vessel containing gamma-HCH was disposed of into the river which became trapped in a trash dam and subsequently contaminated river sediments approximately 300m upstream of the routine monitoring point at Newlyn Bridge. Concentrations of gammaHCH at the Newlyn Bridge monitoring point have declined since the initial pollution event and comply with the Environmental Quality Standard (100 ng/l) for this substance. It is reconmended that no remedial action is required to remove gamma-HCH in the sediments since winter flows are likely to flush the contamination from the river system. A repeat survey to analyse river sediments will be carried out in 1990 to ensure flushing of gamma-HCH.
Publisher: National Rivers Authority
Publication Date: 1989
Publication Place: Exeter
Subject Keywords: RiversWater pollutionPesticidesSediments
Geographic Keywords: EA South WestWest Cornwall and the Fal catchmentCornwall
Extent: n.p. [15]
Total file downloads: 21

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