4. Section 4 of the Principal Act is amended—
(a) by omitting “4 or” from paragraphs (a) and (b) of the definition of “controlled activity”; and
(b) by inserting the following definitions:
“ ‘Commissioner' means the Commissioner for Land and Planning appointed under section 274A;
‘public land' means land identified by the Plan as public land;
‘public street' has the same meaning as in the Motor Traffic Act 1936 .”.