interpretation of the use of a comma with and

Question

My jurisdiction has a planning regulation that has come under interpretive differences recently. The intent of the regulation was that the high water mark survey had to be undertaken and authenticated within 6 months. We are now receiving an interpretation that because of the comma before the word 'and' that the latter requirement for authentication does not need to be done within the 6 month time frame. Here is the regulation for reference:

“Unless exempted by the Authority, an application for planning permission with any setback adjacent to the sea shall include a Mean High Water Mark survey physically defined on ground no more than six months prior to the application being submitted, and the survey plan shall be authenticated by the Department of Lands and Survey.”

Your help in determining the correct reading would be greatly appreciated.

Answer 1

The comma is irrelevant; it has no impact on the sense, and its deletion would not rescue the intended meaning.

The temporal preposition phrase no more...submitted by its position modifies the participle phrase physically defined on ground; that phrase in turn modifies the noun phrase a Mean High Water Mark survey, which is itself a constituent (the direct object of shall include) of the first independent clause.

There's no way that a temporal expression modifying a constituent of one independent clause can be understood to modify a subsequent independent clause, conjoined or not.

The regulator may have intended authentication to fall within the six months prior to submission, but the regulation does not require that. What they should have written is:

Unless exempted by the Authority, an application for planning permission with any setback adjacent to the sea shall include a Mean High Water Mark survey physically defined on ground and authenticated by the Department of Lands and Survey no more than six months prior to the application being submitted.

ADDED:
And one more instance of slovenly drafting you should be aware of: as written, the regulation grants the Department of Lands and Survey no discretion: the survey plan shall be authenticated.