United States, Canada Agree on Use of Channels 63, 64, 68 and 69 Near Border
The FCC and Canada's telecommunications regulator, Industry Canada, have reached an agreement that allows use of TV channels 63, 64, 68 and 69 for public safety communications near the U.S.-Canadian border. A glance at the FCC's CDBS listing of Canadian TV stations hear the border shows one station authorized for channel 63, seven for channel 64, one for channel 68, and nine on channel 69.
The FCC news release describing the agreement
said the border area would be divided into three zones, with each zone having specified primary narrowband and wideband channels for the United States and specified primary narrowband and wideband channels for Canada, with restrictions on effective radiated power and protections against interference to the other country's TV stations. The agreement specifies a maximum power flux density at or beyond the border for stations near the border. Some frequencies are designated "Interoperability Channels" that can be used to allow public safety stations on either side of the border to share information.
I couldn't find the agreement on the FCC's International Agreements
Web page, but it may be available at that location by the time you read this. The agreement was signed on June 15 and June 20, 2005.