MP4 Organic, Metallic, Organometallic Pollutants and Method
Monday, 14 November 2005: 8:00 AM - 6:30 PM in Exhibit Hall

(BAI-1117-854671) Use of in situ hatchbox studies to evaluate water quality effects.

Bailey, H¹, Chalmers, B², Elphick, J¹, ¹ Nautilus Environmental, San Diego, CA, USA² NVI Mining, Campbell River, BC, Canada

ABSTRACT- Laboratory toxicity tests have been criticized on the basis that their results may not reflect site-specific conditions. Conversely, interpreting the results of bioassessment studies may be problematic due to the inability to control for the movements of organisms in the receiving environment, as well as difficulties distinguishing between water quality and habitat effects. Thus, the use of in situ studies may provide an opportunity to quantitatively evaluate the potential effects of a discharge under the conditions found in the actual receiving environment. This presentation describes the approach used at the Myra Falls mine to evaluate the potential for discharge effects in the receiving environment. Eyed trout embryos were placed in hatchboxes at different locations to identify any potential for toxicity in Myra Creek. The reference site was located upstream of the discharge, and potential impact sites were located downstream of the discharge. Hatchboxes were also placed at selected locations to identify possible inputs of contaminated subsurface flows. Both lethal and sub-lethal endpoints were evaluated, including survival, hatching success, and growth.

Key words: cutthroat trout, mining, environmental monitoring