Human and Ecological Risk Assessment - Earthjustice

Section 4.0Risk CharacterizationTable 4-18. Summary of Proven Damage Cases with Fish Consumption Advisories(U.S. EPA, 2007)Proven NODA Damage Case7. Hyco Lake, Roxboro, North Carolina (surfaceimpoundment discharge)Reported Fish Consumption AdvisorySelenium fish consumption advisory11. Belews Lake, NC (surface impoundment discharge) Selenium fish consumption advisory20. Brandy Branch Reservoir, Texas (ash pond discharge) Selenium fish consumption advisory21. Southwestern Electric Power Company Welsh Reservoir,TX (ash pond discharge)22. Texas Utilities Electric Martin Lake Reservoir, TX (ashpond discharge)Selenium fish consumption advisorySelenium fish consumption advisory; elevatedselenium in birdsEPA has also found that CCW contaminants of concern in the damage cases agree withthose exceeding a 1 in 100,000 excess cancer risk or an HQ of 1 in this analysis, buildingconfidence that the risk assessment captures national conditions. Table 4-19 compares theresults from the 2007 draft risk assessment with the damage cases reported in the CoalCombustion Waste Damage Case Assessments (U.S. EPA, 2007) for the groundwater pathway.Table 4-19. Modeled 90th and 50th Percentile Risk Results vs.Reported Groundwater ExceedencesConsistentHuman Cosmetic/2007 Risk Assessment a Damage Cases bConstituent 90th %ile 50th %ileHealthEffects cAestheticEffects dStateStandard eResults as of2007 fAluminum – – – – YesAntimony – – – – NoArsenic T – YesBarium – – – – – YesBeryllium Screened – – – YesBoron – – YesCadmium – – – YesChloride Not Screened – N/AChromium RAF – – UncertainCobalt T – – – NoCopper Screened – – – YesFluoride RAF – – UncertainIron Not Screened – N/ALead – – – YesLithium Not Screened – – N/AManganese RAF UncertainMolybdenum – – – YesNickel RAF – UncertainNitrate/Nitrite – – – – NoSelenium – – YesSilver Screened – – – YesSulfate Not Screened – N/AThallium – – – – NoVanadium RAF – – – Uncertain(continued)April 2010–Draft EPA document. 4-23