or site alteration work pending the determination of Burlington’s
application to enforce compliance with the 2003 by-law. Murray J.
ruled in November 2013 that Airpark was subject to the 2003
by-law: Burlington Airpark Inc. v. Burlington (City),  O.J.
No. 5165, 2013 ONSC 6990, 17 M.P.L.R. (5th) 254 (S.C.J.). That
decision was upheld by this court in June 2014:  O.J. No.
2835, 2014 ONCA 468, 23 M.P.L.R. (5th) 1.
 While those cross-applications were before the courts, Burlington prepared a more stringent by-law to replace the 2003
by-law. By-law 64-2014 was passed on September 22, 2014. By
its terms, the 2014 by-law repealed the 2003 by-law with no
transitional provision to continue the 2003 by-law, and came into
force on the date of its passing.
 The central issue on this appeal is whether Burlington can
require Airpark to apply for a permit under the 2014 by-law for
work Airport did prior to the enactment of that by-law.
 Airpark is a registered aerodrome pursuant to the
Aeronautics Act, R.S.C. 1985, c. A-2 and the Canadian Aviation Regulations, SOR/96-433. It was established in 1962, and provides a
base for corporate airlines, a flight training school, patient and
organ transfer flights and other aviation activities and aviation-related businesses.
 Airpark acquired the aerodrome in 2006, and invested
nearly $4 million in improvements to its infrastructure. These
improvements included widening the main runway, paving the
secondary runway and adding new taxiways and hangars.
 In 2008, Airpark began levelling the land to the west of
the main runway to bring it up to the same grade as the runway and to permit aircraft to taxi safely to and from the runway. This involved the importation of fill. Burlington officials
provided a report to council in 2009 stating that, as the work
related to aeronautics, the work was under federal jurisdiction
and the local municipality’s by-laws did not apply. Airpark
maintains that it performed the fill work on this understanding. Burlington maintains that its position was based on
Airpark’s representations that the fill was in fact for airport
expansion work, that the fill was clean and that the work
would end in the summer of 2009. Burlington alleges that
those representations were untrue.
 In 2013, Burlington began receiving complaints from
neighbouring landowners regarding noise, drainage problems,
dust and traffic safety arising from Airpark’s fill operation. Airpark had filed a severance application to allow it to purchase