No abstract

A good environmental effects monitoring program (EEM) provides answers to clear, well-defined questions. The answers should be quantitative and lead directly to decisions about the effluent being studied and about further EEM studies. Preliminary studies should trigger more in-depth monitoring only when predefined thresholds are exceeded. When in-depth work suggests that further studies are unnecessary, there should be a return to a lower level of effort. These criteria lead directly to a tiered strategy for managing EEM that defines the sequence and choice of studies through successive cycles. The benefits of a tiered approach are (1) rules that all stakeholders can understand and comply with; (2) monitoring limited to that which is essential; and (3) assurance that all appropriate elements are included, but only when necessary. Within the context of the new pulp and paper EEM program, tier testing is an efficient, logical and systematic strategy for managing monitoring.

A new approach to surface water analysis has been investigated in order to enhance the detection of different organic contaminants in Nathan Creek, British Columbia. Water samples from Nathan Creek were prepared by liquid/liquid extraction using dichloromethane (DCM) as an extraction solvent and analyzed by gas chromatography mass spectrometry method in scan mode (GC-MS scan). To increase sensitivity for pesticides detection, acquired scan data were further analyzed by Automated Mass Spectrometry Deconvolution and Identification Software (AMDIS) incorporated into the Agilent Deconvolution Reporting Software (DRS), which also includes mass spectral libraries for 567 pesticides. Extracts were reanalyzed by gas chromatography mass spectrometry single ion monitoring (GC-MS-SIM) to confirm and quantitate detected pesticides. Pesticides: atrazine, dimethoate, diazinone, metalaxyl, myclobutanil, napropamide, oxadiazon, propazine and simazine were detected at three sampling sites on the mainstream of the Nathan Creek. Results of the study are further discussed in terms of detectivity and identification level for each pesticide found. The proposed approach of monitoring pesticides in surface waters enables their detection and identification at trace levels.