The benthic macroinvertebrates were sampled in spring and fall seasons at sites below (MCK 1.6) and above (MCK 1.9) Rogers Quarry. Quantitative samples provided data on total richness, EPT richness (mayflies, stoneflies, and caddisflies = pollution intolerant taxa), and abundance.
 | Recovery of the macroinvertebrate community closely followed declines in fly ash discharges, with the most dramatic improvement from 1989 through 1990 (Figure 1). |
| Since 1990, however, the total number of taxa and the EPT richness have frequently been lower than the range exhibited at reference sites, suggesting that episodic impacts continue to occur. |
| Figure 1. Total Richness and EPT Richness at two sites in McCoy Branch in comparison to the range of richness in reference streams, 1989-1997. |
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Last Modified: April 17, 2001