From: KENT Mavis D
Sent: Tue Sep 29 12:21:33 2009
To: Chris Kimmel; Chaput, Kenneth G
Subject: 2009 Semiannual Data Report
Importance: Normal
I have reviewed the 2009 Semiannual Data Report, dated July 29, 2009, and have the following comments. We may want to have a brief call to discuss the comments and how best to address them. Revision of this report is not necessarily needed, but the comments are applicable to future reports and could be addressed with a response memo or similar.
Semiannual Reporting:
We agreed to move to semiannual reporting, that would include all aspects of monitoring and assessing The Boeing property. The first report of the year would be primarily a data report and the second report would have a more robust performance evaluation. The performance report will need to include RAOs and performance measures as context for the discussion of remedy performance. The data report should have some level of key performance presentation while deferring the complete discussion to the performance report. For example, an ongoing task is monitoring the bioremediation injection so it would be helpful to have some brief statements about whether this is going as anticipated and what some of the data means. My focus is on how is the remedy going in general, where are there persistent elevated contamination areas, and how can we address those to accelerate cleanup.
Corrective Measures Section:
The first sentence is incomplete. In the second paragraph the two monitoring events should be clarified: February was the regularly scheduled site wide monitoring, and May was an injection performance monitoring of a subset of wells (I presume). Clarify why you chose to highlight 1,1,1-TCA (is this specific to the Boeing site?).
Four figures are referenced in this section. The value of Figures 5 and 7 is not clear. Figure 5 contours the “plume” in the TGA but seems misleading since it suggests that the entire plume shrank between February and May when only a small number of wells was sampled. Perhaps the data presented on Figures 5 and 7 could be added to Figure 9 which seems to be portraying the same thing: changes in concentration within the general injection area in the footprint of the building expansion.
Items that I would like a little discussion of in this section include the three potential areas of concern in the upper TSA that are related to areas of elevated concentrations in the TGA (BOP-7, BOP-57ia/ib, and BOP-10). At BOP-7, concentrations of TCE remain high and it seems that the replacement of BOP-22 has eliminated a pathway from the TGA to the TSA. Do the data support this? What is the source of TCE at BOP-7 and will you be evaluating this area for discussions and recommendations in the performance report? At BOP-57 fairly high concentrations are at the top of CU1 with corresponding higher concentrations in the upper TSA. This is the location of the old production well, right? Is the monitoring network for this area adequate? Is there leakage through the CU1? How will you evaluate this area and will you be discussing recommended actions in the performance report? Concentrations at BOP-10 seem fairly localized; what is the source? The only upper TSA monitoring point is at BOP-65 which seems to be side gradient from BOP-10 but has persistent elevated TCE concentrations. Are these two locations related? Is there possible leakage down through the CU1? This area also should be evaluated for potential actions to accelerate cleanup.
Figure 4 portrays the current extent of TCE in the TGA (as of February 2009). It would be useful to highlight the TSA wells on this map, perhaps a different color. Because the impact to the upper TSA is a consideration, it would be useful to add the line demarcating the unsaturated zone for the upper TSA. When looking at the wells where vertical concentration profiles are obtained, and when comparing to TGA concentrations, it would be useful to know what the top and bottom elevations of the CU1 is at those locations. Just a note regarding the EMC reports, elevated concentrations at BOP-60 are not reflected on the upper TSA TCE map for February 2008 on Figure 4-4a. Does this mean that the diffusion bag sample data are not reliable?
Corrective Measures Section:
I a not sure whether the timeline for the building 85-001 project change much over time or not but it would be good to indicate whether it is on track and what the anticipated timing is for big tasks such as well decommissioning and ground construction startup. The third sentence in the first paragraph refers to sampling 5 months after injection; is this the May sampling? Add a little more information on status of injection such as whether detectable injectant is still present and how much longer you expect it to be effective. Do you expect the injectant to have any effect on BOP-7? The second paragraph, fourth sentence indicates weekly sampling for BOD and TOC. Do you expect this to continue? Is this the main performance measure for the effectiveness/persistence of the injectant? It would be useful, although perhaps a little busy, to add to Figure 9 the overall footprint of the area affected by the injection for context.
Those are the comments and questions I have. I am in today and tomorrow, fairly tied up Thursday and out on Friday if you want to set up a time to discuss.