Laserfiche WebLink
0 • <br /> Draft Soils FS Memorandum -6- 14 September 1993 <br /> DDRW, Sharpe <br /> 5. Site is within capture zone of groundwater extraction system. <br /> 6. Wastes were routinely disposed of at other sites. <br /> None of these reasons above provide compelling rationale for no further action for sites <br /> identified as IRP sites without additional elaboration. This is, in part, corroborated in EPAs <br /> comments of 8 November 1989 on the Revised Draft Work Plan (September, 1989). <br /> Comment 4a states that the EPA does not concur on the no further investigation reason if <br /> wastes were deposited prior to the areas being paved. The RI does not address the issue of <br /> when areas were paved in relation to historic disposal activities. <br /> Page 1-103, Section 1.5.1, PS#7 - Bldgs. T-661 and 669; This section describing the RI <br /> efforts at this site is a good example of the poor data presentation that is typical throughout <br /> the RI documents and the Draft Soils FS. First, the title of PS#7 claims to include Bldgs. <br /> T-661 and 669. The text in this section does not mention Bldg. 669. The section refers to <br /> Figure 1.5-2, however, upon examination, Bldg. 669 is approximately 500 feet south of Bldg. <br /> T-661. This section states that a lime pit adjacent to Bldg. T-661 was used for acid disposal. <br /> There is no description of the pit characteristics, such a size, depth, condition of the pit, etc. <br /> The section describes lead contamination of 150 µg1g in the 10 to 15 foot interval of a soil <br /> boring in the pit, however, it does not address possible ground water impacts despite lead <br /> contamination just above the water table at 15 feet here. The primary Maximum Contaminant <br /> Level (MCL) for lead is 15 ppb. Finally, the section states that well 449C is located <br /> downgradient of the site and that this well has never been analyzed for lead. There is no <br /> explanation as to why this well has not been sampled for lead. Figure 1.5-2 does not show <br /> the location of well 449C. A copy of the Annual Progress Report (March 1993) was required <br /> to locate this well and its construction details. Examination of this report shows that well <br /> 449C is approximately 900 feet down gradient of the lime pit, at a depth of 95 feet. A simple <br /> explanation, that there are no nearby shallow monitoring wells downgradient of the site, would <br /> have been more informative. <br /> This example also illustrates the difficulty of evaluating the key information required for <br /> basing decisions solely on the brief descriptions provided on these sites. I find these <br /> descriptions to be inadequate and extremely difficult to work with. The scale of the figures is <br /> too large and does not provide enough detail with which to evaluate conditions at individual <br /> sites. Much better use can be made of tables by summarizing individual site data. Including <br /> sampling data in text also makes it extremely difficult to compare data from other sites. In <br /> some cases, there is probably enough information to accurately assess a site, it is just a matter <br /> of data presentation. Therefore, in the future DDRW, Sharpe should continue to summarize <br /> the data in table format. In some cases, it is impossible to come to a conclusion, because the <br /> data has not been presented or does not exist. In the cases where there is no information, <br /> additional characterization may be necessary in order to assess its potential as a contaminant <br /> source area. <br /> While it is true that all of the regulatory agencies approved the RI documents, new <br /> information has been presented since the November 1990 RI was prepared. The RI was not <br />