Acid Rock in the Great Smokies: Unanticipated Impact on Aquatic Biota of Road Construction in Regions of Sulfide Mineralization

Abstract

After the completion of a highway construction project in Great Smoky Mountains NationalPark in 1963, a fish kill was noted in a small stream draining an area of roadbed fill. After 10 years, the stream remained devoid of fish for at least 8 km downstream from the fill. The downstream water had a pH of 4.5 to 5.9; upstream from the fill the pH was 6.5 to 7.0. The rock material in the fill contains iron sulfide minerals. Other streams in the area flowing on the sulfide-rich rocks also showed low pH values. Survivability tests and stream surveys showed that brook trout cannot tolerate conditions in the stream below the road fill or in a stream flowing over natural outcrops of the same rock used in construction of the road fill. Native salamanders were also adversely affected downstream from the road fill. Chemical analyses of stream water and leaching tests indicated that lowered pH and increased sulfate and metals concentrations derived from the leaching of the sulfide-rich rocks were responsible for the trout and salamander mortalities. A kill of native brook trout (Salvelinus/ontinalis) occurred in 1963 in a small stream (Beech Flats Creek) draining a watershed near the crest of the Great Smoky Mountains in Great Smoky Mountains National Park, North Carolina. The kill was coincident with a construction project in which a new road fill and culvert were built across the stream valley at an elevation of about 1500 m, near Newfound Gap. Brook trout were eliminated from the main stream for at least 8 km below the construction area, but fish in tributaries of the stream were unaffected. A dense whitish to yellowish precipitate coated stream bed rocks for at least 2 km downstream from the road fill.It was assumed that the kill was related to the construction work, probably due to a toxic substance that would be washed away or de-

Effects of stream acidification on lotic salamander assemblages in a coal-mined watershed in the Cumberland Plateau

“…Similarly, larval plethodontids (D. quadramaculatus, D. marmoratus, E. wilderae) were virtually eliminated from a contaminated section of a Blue Ridge stream following exposure to an acidic (pH ¼ 4.5) pyrite-rich drainage from Anakeesta rocks used in a road construction project (Huckabee et al 1975); this event resulted in long-term acidification and pronounced declines in stream-breeding plethodontids (and other macrofauna), which altered the population density and structure of terrestrial-breeding plethodontids (Kucken et al 1994). In a related study, Matthews and Morgan (1982) documented 100% mortality of D. marmoratus larvae after 96-hour exposure to Anakeesta leachates with pH ¼ 3.9-5.0 and elevated concentrations of metals.…”

Using the Eastern Hellbender Salamander in a High School Genetics & Ecological Conservation Activity

“…Small, isolated populations are more susceptible to environmental perturbation and demographic stochasticity, both of which may lead to local extinction (Lande 1988, Wyman 1990. Nickerson et al (2002) cites a study by Huckabee et al (1975) which implicated lowered pH levels and increased sulfate and metal concentrations as the likely contributor to salamander elimination from streams in the Great Smoky Mountains National Park. Salamander kills occurred downstream from road building projects (Huckabee et al 1975).…”

“…Nickerson et al (2002) cites a study by Huckabee et al (1975) which implicated lowered pH levels and increased sulfate and metal concentrations as the likely contributor to salamander elimination from streams in the Great Smoky Mountains National Park. Salamander kills occurred downstream from road building projects (Huckabee et al 1975). Dodd (1997) describes the environmental effects of mining which destroys and alters habitat through toxic pollution, decreased pH levels, and increased siltation.…”

Evaluation of Sulfidic Materials in Virginia Highway Corridors

“…In addition to leaching acid, oxidation of these materials results in volumetric changes which compromise fill stability and may lead to subsidence and pavement buckling (Pye and Miller, 1990). Finally, failure to establish roadside vegetation due to extremely acid soil conditions increases sediments and acid runoff from bare road banks (Miller et al, 1976 (Huckabee et al, 1975;Klapper and Schultz, 1995;Morgan et al, 1982;Nathan and Katz, 1969). Furthermore, the combination of visible pollution and adverse conditions for aquatic life limits recreational uses, such as fishing and swimming in surface waters .…”

“…Furthermore, the combination of visible pollution and adverse conditions for aquatic life limits recreational uses, such as fishing and swimming in surface waters . (Huckabee et al, 1975). Acid leachate with high heavy metal concentrations decimated local aquatic life, in some areas reaching up to 8 km from the roadcut and fill (Mathews and Morgan, 1982).…”