138. In addition to the municipal by-laws, and in particular the by-law adopted under section 150, a person must comply with any conditions the council of the municipality sets pertaining to the conservation of the heritage value of a recognized heritage site if the person
(1) builds a new construction on the site;
(2) changes the arrangement and ground plan of an immovable on the site, makes repairs to it or changes its exterior appearance in any way;
(3) carries out excavations on the site, even inside a building, unless the purpose of the excavation is a burial or disinterment and none of the acts listed in paragraphs 1 and 2 are carried out; or
(4) posts new signs or billboards on the site or alters, replaces or demolishes a sign or billboard.