Definition of Derelict Site: “Derelict Site” means any land which detracts, or is likely to detract, to a material degree from the amenity, character or appearance of land in the neighbourhood of the land in question because of –
(a) the existence on the land in question of structures which are in a ruinous, derelict or dangerous condition, or
(b) the neglected, unsightly or objectionable condition of the land or any structures on the land in question, or (c) the presence, deposit or collection on the land in question of any litter, rubbish, debris or waste, except where the presence, deposit or collection of such litter, rubbish, debris or waste results from the exercise of a right conferred statue or by common law.
At the link is a list of the current derelict sites. Derelict Sites Program Update Nov15_1