I am now searching for the full text of Comare report number 1 of 1986. Two years after the Black report and the TV program which highlighted the leukemia cluster around Sellafield (1984). These occurred prior to Chernobyl.
In my search I found the following archive record of the government response to the first comare report: http://www.nationalarchives.gov.uk/about/news/newly-released-files-1985-1986/prime-ministers-files-prem-1986/ which if you scroll down the page records this:
Report on leak at Windscale: policy towards Sellafield; environmental pollution; report on incidence of cancer in west Cumbria; report of the Committee on Medical Aspects of Radiation in the Environment; part 1
Catalogue reference: PREM 19/1741
Date range: 28 July 1980 – 22 July 1986
Patrick Jenkin suggests a ‘Sellafield dimension’ to Government policies where financial compensation would be given to areas near nuclear plants, such as the Workington Enterprise Zone. This is rejected by David Pascall of the Policy Unit (1 June 1984). The Black Report published in July 1984 causes concern as it looks at leukaemia among young people in Seascale, near Sellafield (17 July 1984). Correspondence between Thatcher and the Taoiseach, Garret Fitzgerald in March 1986 demonstrates Irish concerns over the safety of Sellafield. Advisor Michael Addison describes the Committee on Medical Aspects of Radiation in the Environment (COMARE) report as having come at ‘an unfortunate time, after Chernobyl.” end quote. Source: UK National Archives, Prime Minister’s files (PREM) 1986. No surprises there. Unfortunate given the number of afflicted children, Thatcher you old demented dead devil.