I've been lurking here for a while, but since I'm a scientist and not an aircraft researcher, never dreamed I would be posting.
My scientific background is relevant to this report, though, so here goes. This report is fascinating and thorough, and the conclusions are well thought-out.
I do see a couple of minor discrepancies having to do with the units reported on some of the analyses. These do not appear to affect any of the conclusions of the report, however, but I note them for clarity and also because I find it important to have correct units, because later researchers will often refer back to earlier reports and will rely on the units as reported.
The apparent discrepancies are:
Under "What did 2-9-S-1 contain?" this statement:
"The test results showed mercury in the interior at a level of 4 micrograms (µg) per 50 milliliters (ml) of solute."
The analytical reports by EAG show that the concentration in the liquid was 4 micrograms per liter. (The Coke bottle report by EAG shows it as 0.004 mg/L, which is the same as 4 ug/L.)
It appears, therefore, that there were 50 mL of leachate containing 4 ug/L of mercury, rather than 50 mL containing 4 ug of mercury. (4 ug in 50 mL would be 80 ug/L.)
The assumption that there were 50 mL containing 4 ug/L of mercury was used in the spreadsheet where this concentration was converted to a mass per surface area figure for comparison with background surfaces. On that spreadsheet, it appears that the units in cell A1 are ug/L, and in cell H1 should be ug Hg per cm2, not ug per liter per cm2. (The liters canceled out.)
Again, I think the numbers are correct, but if I'm following this then the units just need to be tweaked.
I'm now going to be away from computers for the next week. If I'm wrong here, please excuse me!
Jennifer,
I see now you are exactly correct. The units should only have been expressed in micrograms per liter. 4 mcg in 50 ml is incorrect. The concentration of Hg on the interior surface of 2-9-S-1 should be 4 mcg per
1 liter. The concentration of Hg on the interior surface of the authentic Dr. Berry's Freckle Ointment jar should be 120 mg per 1 liter. As Greg George has explained, we converted mcg per 1 liter back to the original concentration units in mcg per 50 ml (the original leachate volume after dilution) by dividing by 20. We did this to approximate as closely as possible the actual amount of mercury, .2 mcg, leached from the jar surface, and then we divide by surface area in order that we might have a means of comparing our Hg levels to standards of threshold contamination levels set by a state agency in New Jersey.
Notably, the calculation in the report of how many times our Hg levels exceeded the N.J. standard was correct, as you rightly suspected. The units, however, were misleading. Fortunately, we did not repeat the error in our tabular summary of results, which occurred later in the report. There, all results are expressed in micrograms per liter.
One problem of this error in units is that it could be interpreted as overstating the Hg by a factor of 20. Notably, you not only caught the error but figured out what we intended to say. Thanks very much for help in clarifying this point.
Joe Cerniglia ~ TIGHAR #3078ECR