49—Causing site contamination (section 103D)
(1) Subject to this regulation, the commencement or revival of a particular use of a site is a prescribed change of use for the purposes of section 103D(2) of the Act if—
(a) the use supersedes a previous use of the site; or
(b) the commencement of the use or the revival of the use follows upon a period of non-use; or
(c) the use is additional to a previously established use of the site which continues despite the commencement of the new use.
(2) The revival of a use of a site after a period of discontinuance will be regarded as the continuation of an existing use unless—
(a) the period intervening between the discontinuance and revival of the use exceeds two years; or
(b) during the whole or a part of the period intervening between its discontinuance and revival, the use was superseded by some other use.