law: 4. Provisions of this Act not to apply in certain cases.-
  During the period of operation of this Act, no relief shall be available under the provisions of section 3 in respect of the following encroachment or unauthorised development, namely:-
  (a) encroachment on public land except in those cases which are covered under clauses (a), (b) and (c) of sub-section (1) of section 3;
  (b) removal of slums and Jhuggi-Jhompri dwellers, hawkers and urban street vendors, unauthorised colonies or part thereof, village a badi area (including urban villages) and its extension in accordance with the relevant policies approved by the Central Government for clearance of land required for specific public projects.