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Dominant Family: The dominant family was Heptageniidae (mayfly). Heptageniidae dominated 39.5% of the sample, and has a tolerance value of 4 on a scale of 0 -10 (the lower the tolerance value, the lower their tolerance to pollution). These flathead mayflies have flattened head, body, and legs. This makes them well adapted to quick water currents by allowing water to flow over their body with less friction. They live on the surface of rocks, logs, vegetation, and leaves; and they feed on algae and microorganisms growing on rocks. (Guide to Aquatic Invertebrates of the Upper Midwest, R.W. Bouchard, Jr). Number of Families: In 2012, 18 families were identified in the sample. This compares to 13 families in 2011 and 18 families in 2010. In general, a more diverse sample suggests a healthier stream environment. APT: Ephemeroptera - Plecoptera - Tricoptera (Mayfly - Stonefly - Caddisfly) are three Orders of invertebrates with low tolerance to pollution. The more of these families in a sample, the better. More than 10 -12 families is considered good. In 2012, 5 EPT families were identified in the sample and made up 55% of the sample. 4.1.4b Field Sampling Results for Hardwood Creek "Below" Site Historical Field Results for Hardwood Creek `Below' Site Date # Identified Family Biotic Index EFT Number of Families Dominant Family Dominant Family Overall Field Sampling Results: 9/20/10 136 5.1 3 16 Gammaridae 38% 8/20/11 154 4.4 3 11 Gammaridae 60.4% 10/2/12 210 4.6 4 20 Gammaridae 51.4% ■ Ephemeroptera ■ Plecoptera • Tricoptera 1 DIptera ▪ Coleoptera ▪ Oligochaeta II Other Hardwood Creek `Below' Data Summary Family Biotic Index (FBI): Our 2012 SHEP field sampling results produced a score of 4.6 for the Hardwood Creek `Below' site. This score corresponds to a "Good" rating on • • •