t and that from the steam plant may be ignored.
ATSDR Response: A summary has been added to the revised document (to the healthconsultation; not in this appendix). We have also reconfigured the ISC air dispersion modelto include potential contributions from both PGDP steam plant and the TVA facility. Basedon 1998 and 1999 Toxic Release Inventory data for the TVA facility , the instantaneousnickel air emissions average ~0.0025 g/sec. Assuming that those later years are similar tothe years of PGDP nickel smelter emissions, the instantaneous TVA release is about 20times lower than the PGDP smelter release (0.05 g/sec) and is dispersed from an 800+ footstack. Similarly, using standard emission factors for coal and oil combustion and annual fuelusage rates, instantaneous nickel emissions from the PGDP steam plant averaged 0.00009g/sec, which is 500 times lower than the smelter emissions (dispersed from two adjacent 110foot stacks). The results of the revised air dispersion models indicate no differences in theshort term or annual distributions of nickel. All estimated concentrations are still well below levels of health concern.
- Kentucky Environmental Oversight: List of Hazardous Waste and RadionuclideParameters Currently Analyzed and Monitored by the Commonwealth of Kentuckyat the Paducah Gaseous Diffusion Plant (Name Redacted) includes nickel, nickelcompounds, nickel carbonyl, and nickel cyanide. What PGDP operation(s) producesthis waste stream? Did this Health Consultation and/or the Public Health Assessmentfor PGDP include this source of nickel? Is this nickel monitored in air, soil, or water?
- Phase II Independent Investigation of the Paducah Gaseous DiffusionPlant...February 2000, section 3.2.5 smelting, refers to scrap metal recovery recordsbeing "...removed by another DOE team investigating scrap metal recovery at theplant." Has ATSDR reviewed those records? Additionally, the same section of PhaseII refers to "a 1972 study of radionuclides in scrap..."; did ATSDR review that study?Further, a chart on page 74 of Phase II indicates smelting activities at C-746 (A),PGDP, from the 1950's to 1990. This Health Consultation only considers nickelsmelting from 1977 to 1986; was nickel smelted at PGDP at any other time? Thus,was the 37 million pounds smelted during that period the total amount of nickel eversmelted at PGDP?
- ATSDR, 2001 Public Health Assessment for the Paducah Gaseous Diffusion Plant(USDOE), May 14, 2001. (see page 38) When determining the contaminants ofconcern for the May 14, 2001 health assessment did the ATSDR review the historicalreleases from the nickel smelting and lead "recycling" operations at PGDP? (see page57-Table 11) What chemical form of nickel is considered here? (see page 68-Table15A) When the ATSDR determined off-site soil concentrations of nickel did notexceed health guidelines were they able to determine the source of that nickelcontamination? What was the source? (see page 17-Table 2) Nickel was detected in 42of 110 off-site groundwater samples. What was the source of this nickel? (see page 19)"...nickel (was) only detected downwind of the PGDP smelter and mainly up-wind ofthe TVA plant. What was the source of that nickel? (see page 65-Table 14A) Whenthe ATSDR estimated nickel posed no health problem to workers and visitors of theWKWMA did they consider the concentration of nickel in ash spread on the roadsthroughout the refuge and how nickel laden dust rises from roads when vehiclestravel them? (see page 74-Table 17A) What was the source of the nickelcontaminating the deer liver and muscle? (see page 146 #3) "...you can always ask forit to be explained in the form that is easiest for you to understand." (Thus) From1977 to 1982 how many pounds of non-radiologically contaminated nickel wasreleased from the PGDP nickel smelter stack? From 1983 to 1986 how many poundsof radiologically contaminated nickel was released from the PGDP nickel smelterstack? At the time ATSDR prepared the May 2001 Health Assessment were theyaware nickel smelting and lead "recycling" operations were conducted at PG