 conclusion is based on review of amodel and that model is based on data that is not entirely correct.
A valiant effort was made given the amount of information available/provided to theresearchers preparing the report. Additional effort needs to be made to add thesampling information available at DOE to the review and models. A huge amount ofprocess information was removed from C-746A at some time between 1987 and 1994.Managers of the smelter could indicate what types of records were kept anddocument archivists for the site could indicate where this information was taken.Some information was removed from the building in 1995 and uniquely "stored" indrums destined for disposal. Studies such as these need to be put together to ascertainthe cumulative affect of all of the sources of contamination and see if off-site residentswould have been within the radius of influence. Doing this in a location-by-locationmanner is akin to informing the family of a torture victim that everything should befine because each of the thousand cuts was studied and found to be insignificant.
ATSDR Response: This consultation specifically addresses releases from the C-746Asmelters. Appropriate revisions have been made to clarify the purpose of the healthconsultation. Releases from uranium metal operations at the C-340 complex were evaluatedas part of total uranium releases from the entire PGDP facility and are included in the PGDP Public Health Assessment.
As you have indicated there was a uranium metal production operation in building C-340.1985 annual uranium emissions from the C-340 operations are provided in Table 1 of the1985 Environmental Monitoring Report . Annual emission values for U234, U235, andU238 are 7.1E-6, 3.3E-7, 2.6E-5 Ci/yr, respectively. As these values are all at least 10,000times lower than the emissions from other previously evaluated sources (C-310 stack, C-400group, seal/wet air exhaust, C-710 laboratory) for earlier years (1956-59), they do notcomprise a significant additional source of radionuclide emissions (see Table E-1 inAppendix E for uranium values evaluated for specific release years). For example, thepreviously evaluated 1956 annual releases included 1.6 Ci/yr for U234, 0.08 Ci/yr forU235, and 3.5 Ci/yr for U238.
As the much higher 1956 releases did not result in off-site exposures of public healthconcern, the measured 1985 emissions from uranium metal production in C-340 are belowlevels of public health concern. We will make appropriate revisions in the Public HealthAssessment document to ensure that potential releases from C-340 uranium operations areexplicitly referenced even though such emissions do not constitute a significant source.
ATSDR Response: The Commentor is correct in indicating that the entire smelting processincluded several operations in addition to the smelting furnace. Scrap nickel was subjected tophysical grinding in order to produce a small, uniform feed material. According to airpermit documents and personal communications  this process occurred in enclosedcontainers and emissions were subject to filtration before release to the atmosphere. Aftergrinding, the nickel chips were processed through the calciner to remove hydrogen fluoride(HF). This process was designed to remove gaseous HF and did not release particulatematerials. Although both of these processes may contribute to contamination of the on-siteprocessing facilities, only the smelting furnace emissions served as a significant source ofnickel particulates for off-site dispersion.
ATSDR Response: We will review the document to ensure that all conclusion statementsexplicitly indicate that the results are referenced as modeled (or estimated) airconcentrations. In the absence of directly measured air concentrations, modeled datarepresent the best available information. It is also important to point out that thisconsultation does use measured stack concentrations as the basis for determining the sourceor emission concentrations which is the source term for the dispersion modeling. We haveevaluated extensive amounts of air monitoring d