(1) If the Chief Agricultural Officer shall refuse any application for the registration of an engine, made under Regulation 4 hereof, he shall give notice thereof in writing to the applicant stating the grounds of refusal.
(2) If at any time after an engine has been registered the Chief Agricultural Officer shall be of opinion that payments may not properly be made under the act, he shall forthwith notify the owner in writing that it is his intention to cancel the registration of the engine, and shall state the grounds of the proposed cancellation; and if within 7 days of such notification the owner does not signify his intention to appeal against such decision, the Chief Agricultural Officer shall cancel such registration.