Activities over the last century have left an environmental legacy that includes toxic waste sites, abandoned mines, contaminated military installations, leaking fuel storage depots, and other hazards to human health and the environment.

Recognizing the need to take action, the Canadian Council of Ministers of the Environment (CCME) and the Government of Canada negotiated a joint five-year National Contaminated Sites Remediation Program (NCSRP) in 1989. This program assisted in remediating orphaned high-risk contaminated sites (sites for which a responsible party cannot be found, or where the property owner is unable or unwilling to finance remediation) while promoting Canada's environmental technology industry. A total of 45 contaminated sites across Canada was addressed under the National Contaminated Sites Remediation Program. In addition, 55 site developments and demonstrations of remediation technology projects were undertaken. Under this program, a method for classifying contaminated sites according to their current or potential adverse impacts on human health and the environment was also developed.

In 1990, to address contaminated sites on federal Crown land, Environment Canada committed to assisting custodians with identifying, assessing, and remediating high-risk contaminated sites within their jurisdictions. As a result, 325 federal sites were investigated and remediation was initiated at 14 sites requiring immediate attention.

The creation of the Contaminated Sites Management Working Group (CSMWG) in 1995 was a major step forward in addressing federal contaminated sites. This interdepartmental group, made up of custodians, has been instrumental in the development of an interdepartmental strategy to deal with contaminated sites.

In spite of these early efforts, both the Auditor General and the Commissioner of the Environment and Sustainable Development remained critical of federal contaminated sites management. The primary concern was the absence of an adequate legislative framework and a clearly defined action plan to address federal sites.

The 2002 Report of the Commissioner of the Environment and Sustainable Development concluded that the federal government had failed to address federal contaminated sites adequately. Criticisms included a lack of information on the number of federal contaminated sites in Canada; the failure to produce an action plan to deal with high-risk sites in a timely manner; and the need for stable, long-term funding to manage the problem.

Recognizing the need for a coordinated approach to address these concerns, the government responded.