2640 Boulevard Laurier
Québec QC G1V 5C2
Telephone: 418 686-4875
Fax: 418 643-8177
according to http://www.sepaq.com/contact/
Prior to the municipal amalgamations of several years ago, this address was in Sainte-Foy QC, but it is now in Québec QC.
I would also like to add the website http://www.sepaq.com/ and the following description, taken from the website:
Sépaq manages over 80,000 km2 of natural territories spread out among 16 administrative regions and 18 tourist regions of Québec. Its mission is to ensure the accessibility, development and protection of these public facilities for the benefit of its clientele, the regions of Québec, and future generations.