PM19 Field-Based Effects Measures
Exhibit Hall
8:00 AM - Monday
(PM296) Ecological effects of lead mining in streams of the Missouri Ozarks.
Allert, A.1, Fairchild, J.1, Besser, J.1, Schmitt, C.1, Poulton, B.1, Brumbaugh, W.1, 1 USGS, Columbia, MO, USA
ABSTRACT- The Viburnum Trend extends through the Black River drainage of southeast Missouri and is one of the largest producers of lead ore in the world. Mining interests seek to expand lead exploration in the adjacent Mark Twain National Forest and the Ozark Scenic Riverways areas of southeastern Missouri. We studied the structure of fish and invertebrate communities at 12 sites in or near the Black River drainage to determine if existing lead mining activities were having effects on biological communities. Stream surveys were conducted at three reference sites with no known upstream mining activities; 9 sites downstream of known mining areas were also sampled. Surface and pore-water samples were collected in riffle habitats (i.e., coarse substrate) and analyzed for metals, major cations, dissolved organic carbon, sulfate, and ammonia. Physical stream habitat was characterized using microhabitat-level variables (i.e., velocity, depth, substrate composition) as well as landscape-level variables (i.e., drainage-basin area, land-use, and channel morphology). Surface and pore-water concentrations of lead and zinc were below chronic water quality criteria (12.9 and 265 
g/L, respectively) at all sites. However, sculpins, crayfish and snails were absent from several sites immediately below active mines. Fish densities were also lower at some sites downstream of mines. These results support the findings of previous biomarker and toxicity studies which indicate that mining is having impacts on biota in the Black River drainage near the Viburnam Trend.
Key words: stream communities, mining, metals, micro- and landscape habitat