Deposits of lead (Pb) and other metals in southeastern Missouri, USA have been exploited since the 1700s. Metal contamination of fish and other aquatic biota, alteration of fish and invertebrate communities, and public health advisories against human consumption of Pb-contaminated fish have resulted. The Little Saint Francis River (LFSR) and its tributaries, which drain the mining-affected areas of Madison County, is inhabited by the St. Francis River crayfish (Faxonius quadruncus; formerly Orconectes quadruncus), an endemic species that has been petitioned for Federal listing as an endangered species. Crayfish population density surveys and in-situ toxicity tests with laboratory-reared F. quadruncus were conducted at sites upstream and downstream of historical mining areas. These data consist of attributes of habitat quality and water quality from study sites located in the LSFR watershed, Madison County, Missouri and attributes of growth and survival of crayfish (F. quadruncus) from 56 day in-situ exposures at the study sites.

These data are comprised of measurements of metals (cobalt, nickel, copper, zinc, cadmium, and lead), anions (fluoride, chloride, nitrite, bromide, nitrate, sulfate, and phosphate), dissolved organic carbon, and major cations (sodium, magnesium, potassium, calcium, manganese, iron, and strontium) in surface and pore water samples collected during an assessment of the impacts of mining-related metals on the keystone crayfish species, Orconectes quadruncus, in the St. Francois draininge in Madison County, Missouri USA.

Historical lead mining in Madison County, Missouri, USA has left a legacy of metals contamination. Laboratory studies were conducted to examine the effect of water hardness and age of crayfish on the toxicity of environment-based metals mixture. Additionally, the effects of chronic exposure to a metals mixture to egg development in adult crayfish were assessed. These data are comprised of measurements of elements (i.e., cobalt, nickel, copper, zinc, cadmium, lead) in tissue samples (crayfish whole bodies, ovaries, leaves, feed) collected during laboratory-based diluter exposure studies.

Historical lead mining in Madison County, Missouri, USA has left a legacy of metals contamination. Laboratory studies were conducted to examine the effect of water hardness and age of crayfish on the toxicity of environment-based metals mixture. Additionally, the effects of chronic exposure to a metals mixture to egg development in adult crayfish were assessed. These data are comprised of measurements of elements (i.e., cobalt, nickel, copper, zinc, cadmium, lead), major anions (e.g., chloride, sulfate), dissolved organic carbon, and major cations (e.g, sodium, calcium, magnesium) in water samples collected during laboratory-based diluter exposure studies. Measurements of elements (i.e., cobalt, nickel, copper, zinc, cadmium, lead) in tissue samples (crayfish whole bodies, ovaries, leaves, feed) collected during laboratory-based diluter exposure studies are also provided.

Historical lead mining in Madison County, Missouri, USA has left a legacy of metals contamination. Laboratory studies were conducted to examine the effect of water hardness and age of crayfish on the toxicity of environment-based metals mixture. Additionally, the effects of chronic exposure to a metals mixture to egg development in adult crayfish were assessed. These data are comprised of measurements of elements (i.e., cobalt, nickel, copper, zinc, cadmium, lead), major anions (e.g., chloride, sulfate), dissolved organic carbon, and major cations (e.g, sodium, calcium, magnesium) in water samples collected during laboratory-based diluter exposure studies.

Laboratory studies were conducted to examine the effect of water hardness and age of crayfish on the toxicity of environment-based metals mixture. Additionally, the effects of chronic exposure to a metals mixture to egg development in adult F. quadruncus were assessed. Mortality and growth of F. quadruncus were assessed. These data consist of attributes of water quality from toxicity tests and attributes of growth and survival of crayfish (F. quadruncus) from laboratory diluter studies.

For the Ecological Risk Assessment Report, EPA collected these samples, consisting of benthic invertebrates (crayfish), from three contaminated locations in the Carson River upstream from Lahontan Reservoir (Santiago Ruins, Dayton State Park, and Fort Churchill) and one background location (Ruhenstroth Dam). As a component of the ecological assessment for the Carson River Mercury Site, a survey of benthic macroinvertebrates was conducted to evaluate the potential adverse effects of mercury in surface water and sediment of the Carson River. Measures of benthic community response to mercury contamination derived from the benthic survey are presented in this the EcoRisk Assessment, Appendix C. A characterization of the existing environment at the sampling locations-including the habitat characteristics, fish and wildlife populations, and surrounding land use. Rapid BioAssessment Protocol II (RBP) involves the standardized collection, enumeration, and identification of major benthic taxa to the family level in riffle/run habitats. Standard data sheets are used to record results at each sampling. location. Collections are compared to a reference location, and an evaluation is made as to the impairment, or lack thereof, of the benthic community from stressors within the watershed. The biological condition of the community can be ranked according to three categories of impact: nonimpaired, moderately impaired, or severely impaired, where the degree of impairment implies less than optimal community structure, the loss of intolerant species, and dominance by a few tolerant taxa compared to background. RBP II also involves assessment of habitat characteristics such as stream flow, bottom conditions, and riparian vegetation. In addition, standard water quality parameters such as dissolved oxygen, temperature, pH, conductivity, color, and turbidity are determined. The RBP II was conducted on August 17 and 18, 1994 during a period of drought. The EPA is publishing this data in support of the Carson River Mercury NPL Site in Nevada. Data was compiled and evaluated for the OU1 Remedial Investigation Report (EPA, 1994) as well as the OU2 Remedial Investigation Report (EPA, 2017), describing the nature and extent of contamination from the Site, primarily the Ecological Risk Assessment Report. The RI report also contains the Human Health Risk Assessment. Literature and other source Hg data are summarized in the RI for surface waters, sediments, and biological tissues.

For the Ecological Risk Assessment Report, EPA collected these samples, consisting of benthic invertebrates (crayfish), from three contaminated locations in the Carson River upstream from Lahontan Reservoir (Santiago Ruins, Dayton State Park, and Fort Churchill) and one background location (Ruhenstroth Dam). As a component of the ecological assessment for the Carson River Mercury Site, a survey of benthic macroinvertebrates was conducted to evaluate the potential adverse effects of mercury in surface water and sediment of the Carson River. Measures of benthic community response to mercury contamination derived from the benthic survey are presented in this the EcoRisk Assessment, Appendix C. A characterization of the existing environment at the sampling locations-including the habitat characteristics, fish and wildlife populations, and surrounding land use. Rapid BioAssessment Protocol II (RBP) involves the standardized collection, enumeration, and identification of major benthic taxa to the family level in riffle/run habitats. Standard data sheets are used to record results at each sampling. location. Collections are compared to a reference location, and an evaluation is made as to the impairment, or lack thereof, of the benthic community from stressors within the watershed. The biological condition of the community can be ranked according to three categories of impact: nonimpaired, moderately impaired, or severely impaired, where the degree of impairment implies less than optimal community structure, the loss of intolerant species, and dominance by a few tolerant taxa compared to background. RBP II also involves assessment of habitat characteristics such as stream flow, bottom conditions, and riparian vegetation. In addition, standard water quality parameters such as dissolved oxygen, temperature, pH, conductivity, color, and turbidity are determined. The RBP II was conducted on August 17 and 18, 1994 during a period of drought. The EPA is publishing this data in support of the Carson River Mercury NPL Site in Nevada. Data was compiled and evaluated for the OU1 Remedial Investigation Report (EPA, 1994) as well as the OU2 Remedial Investigation Report (EPA, 2017), describing the nature and extent of contamination from the Site, primarily the Ecological Risk Assessment Report. The RI report also contains the Human Health Risk Assessment. Literature and other source Hg data are summarized in the RI for surface waters, sediments, and biological tissues.

For the Ecological Risk Assessment Report, EPA collected these samples, consisting of benthic invertebrates (crayfish), from three contaminated locations in the Carson River upstream from Lahontan Reservoir (Santiago Ruins, Dayton State Park, and Fort Churchill) and one background location (Ruhenstroth Dam). As a component of the ecological assessment for the Carson River Mercury Site, a survey of benthic macroinvertebrates was conducted to evaluate the potential adverse effects of mercury in surface water and sediment of the Carson River. Measures of benthic community response to mercury contamination derived from the benthic survey are presented in this the EcoRisk Assessment, Appendix C. A characterization of the existing environment at the sampling locations-including the habitat characteristics, fish and wildlife populations, and surrounding land use. Rapid BioAssessment Protocol II (RBP) involves the standardized collection, enumeration, and identification of major benthic taxa to the family level in riffle/run habitats. Standard data sheets are used to record results at each sampling. location. Collections are compared to a reference location, and an evaluation is made as to the impairment, or lack thereof, of the benthic community from stressors within the watershed. The biological condition of the community can be ranked according to three categories of impact: nonimpaired, moderately impaired, or severely impaired, where the degree of impairment implies less than optimal community structure, the loss of intolerant species, and dominance by a few tolerant taxa compared to background. RBP II also involves assessment of habitat characteristics such as stream flow, bottom conditions, and riparian vegetation. In addition, standard water quality parameters such as dissolved oxygen, temperature, pH, conductivity, color, and turbidity are determined. The RBP II was conducted on August 17 and 18, 1994 during a period of drought. The EPA is publishing this data in support of the Carson River Mercury NPL Site in Nevada. Data was compiled and evaluated for the OU1 Remedial Investigation Report (EPA, 1994) as well as the OU2 Remedial Investigation Report (EPA, 2017), describing the nature and extent of contamination from the Site, primarily the Ecological Risk Assessment Report. The RI report also contains the Human Health Risk Assessment. Literature and other source Hg data are summarized in the RI for surface waters, sediments, and biological tissues.

Data was collected in association with the exposure of aqueous nickel (NiCl2-H2O) to juvenile crayfish (Faxonius virilis) for 29 days at different concentrations to observe any differences in growth (after 28 days) and food consumption (on day 29). Data for the growth component of the study included crayfish wet weight (initial and final), final carapace length, and crayfish sex. The food consumption data included measurement of blood worms (by wet weight) consumed in a 24-hour period. Daily in situ water quality data included temperature, pH, conductivity, and dissolved oxygen. Bench water quality data includes ammonia, hardness, and alkalinity. Analytical chemistry data includes nickel concentration, dissolved organic carbon, cations, and anions. Additional data was also collected to calibrate bloodworm consumption data.