Effects of High Salinity Wastewater Discharges on Unionid Mussels in the Allegheny River, Pennsylvania

Abstract

We examined the effect of high salinity wastewater (brine) from oil and natural gas drilling on freshwater mussels in the Allegheny River, Pennsylvania, during 2012. Mussel cages (N = 5 per site) were deployed at two sites upstream and four sites downstream of a brine treatment facility on the Allegheny River. Each cage contained 20 juvenile northern riffleshell mussels Epioblasma torulosa rangiana). Continuous specific conductance and temperature data were recorded by water quality probes deployed at each site. To measure the amount of mixing throughout the entire study area, specific conductance surveys were completed two times during low-flow conditions along transects from bank to bank that targeted upstream (reference) reaches, a municipal wastewater treatment plant discharge upstream of the brine-facility discharge, the brine facility, and downstream reaches. Specific conductance data indicated that high specific conductance water from the brine facility (4,000–12,000 µS/cm; mean 7,846) compared to the reference reach (103–188 µS/cm; mean 151) is carried along the left descending bank of the river and that dilution of the discharge via mixing does not occur until 0.5 mi (805 m) downstream. Juvenile northern riffleshell mussel survival was severely impaired within the high specific conductance zone (2 and 34% at and downstream of the brine facility, respectively) and at the municipal wastewater treatment plant (21%) compared to background (84%). We surveyed native mussels (family Unionidae) at 10 transects: 3 upstream, 3 within, and 4 downstream of the high specific conductance zone. Unionid mussel abundance and diversity were lower for all transects within and downstream of the high conductivity zone compared to upstream. The results of this study clearly demonstrate in situ toxicity to juvenile northern riffleshell mussels, a federally endangered species, and to the native unionid mussel assemblage located downstream of a brine discharge to the Allegheny River.

Unconventional oil and gas spills: Materials, volumes, and risks to surface waters in four states of the U.S.

“…Wastewater is often high in salinity, toxic trace elements, naturally occurring radioactive materials, and other constituents depending on the producing formation and fluid mix involved in fracturing (Rowan et al 2014, Lauer et al 2016. Exposure to wastewater has been shown to increase plant mortality of terrestrial plants (Adams 2011), reduce juvenile mussel survival rates (Patnode et al 2015), and lower streambed microbial diversity (Akob et al 2016).…”

Forensic tracers of exposure to produced water in freshwater mussels: a preliminary assessment of Ba, Sr, and cyclic hydrocarbons

“…comparison to previous studies. The elevated TDS and Cl concentrations are known to cause high mortality among juvenile freshwater mussels 36 . The chloride concentrations in this study (low dose = 1,240 and high dose late = 4,470 mg/L) fall within the ranges (1,026-5,190 mg/L) used by previous studies to evaluate mortality associated with salinity 34 .…”

“…Unionid mussels (Lampsilis Siliquoidea) exposed to elevated salinity in the form of high Cl concentrations from KCl and NaCl salts or synthetic inorganic mixtures that represent produced waters resulted in increased mortality and decreased growth [33][34][35] . In cages placed downstream of an oil and gas discharge, high mortality was observed in riffleshell mussels (Epioblasma torulosa rangiana) 36 . Another study demonstrated that freshwater mussels downstream of produced water discharges incorporated strontium into their shell material with 87 Sr/ 86 Sr signatures similar to that measured in oil and gas wastewaters 37 .…”

Response of the mollusc communities to environmental factors along an anthropogenic salinity gradient

“…Many previous studies have shown that increasing salinity results in the elimination of sensitive taxa and their replacement by eurytopic species (e.g. Williams et al 1990;Boets et al 2012;Kefford et al 2012;Arle and Wagner 2013;Szöcs et al 2014;Patnode et al 2015). Salt-tolerant species including alien species usually become greatly abundant as a result of a lack of competition (an additional effect of a decrease in species richness) and then communities became monospecific (Williams et al 1990;James et al 2003;Carver et al 2009;Bäthe and Coring 2011).…”

“…This could be explained by the fact that the subhaline ponds were stocked with the fish that are required for the development of its glochidia and are a good vector for its dispersion (Pip 1986). All of the life stages of unionid mussels are sensitive to an elevated content of chlorides (Bringolf et al 2007), but glochidia are particularly sensitive to acute exposure (Gills 2011; Echols et al 2012;Patnode et al 2015). Beggel and Geist (2015) found that a chloride concentration above 5962 mg L −1 caused the death of A. anatina glochidium in laboratory conditions, whereas according to Canadian Water Quality Guidelines for the Protection of Aquatic Life (2011), the short-term exposures to chloride levels above 640 mg L −1 may pose the greatest toxic effects on glochidia of certain freshwater mussel species (CCME 2011).…”