These central registry files were created by a variety of operational units of the Environmental Protection Service (EPS) in Environment Canada. The general mandate of the Service revolves around the development of policies and programmes for the protection of the environment through the prevention, reduction, or elimination of harmful effects of pollutants on human health and the environment. All of the files are drawn from the 4000 block of the department's block numeric file classification system, a block that was reserved for the exclusive operational use of the EPS. Primary environmental protection subject files concerning the following topics are included in this accession: policy development, fuels, chemical and industrial processes, thermal power, nuclear programmes, ecological impact appraisals and environmental impact assessments, presticides, federal activities, waste management and water pollution.
These records themselves are rather atypical and quite unlike other accessions of EPS operational files. In 1985 the EPS merged with the Environmental Conservation Service to form the Conservation and Protection Service (CPS); as a result of this merger, a new file classification system was developed. EPS records that were of continuing operational value to the department were to be brought forward and integrated into the new system. In the case of this particular accession, EPS records from the old file classification system were unfortunately removed from their old file jackets, stripped of all photocopies, and loosely filed with a view towards integrating the surviving documentation into a new set of CPS files. This last step never took place and so records management personnel at Environment Canada were forced to recreate the former EPS file classification system by grouping all records pertaining to the same primary under a general file number. The original secondary and tertiary file numbers have been obfuscated by these events, but a shelf list, included in the finding aid to this accession, will allow researchers to link secondary and tertiary file numbers to the surviving primary file classification number.