Section 46(2)(b) in West Bengal Town and Country (Planning and Development) Act, 1979
(b)without prejudice to the generality of clause (a) of this sub-section the concerned authority may impose conditions(i)to the effect that the permission granted is only for a limited period and that after the expiry of that period, the land shall be restored to its previous condition or the use of the land permitted shall be discontinued;(ii)for regulating the development or use of arty other land under the control of the applicant or for the carrying out of works on any such land as may appear to the authority expedient for the purpose of the permitted development.