06:45 Oct 25, 2011 

I did not look at this soon enough though yes, it is still the same text from Lower Saxony and no, therefore the AHD with reference to Australia would not make sense though I'm glad to have clarification beacuse I've run across that before and did not know if I could apply it in this context. Thank you both.

20:50 Oct 22, 2011 

we're still talking about the Bentheim Sandstone, which is distributed around Bad Bentheim in the western Lower Saxony, "ahd" refers definitely not to the Australian Height Datum

18:36 Oct 22, 2011 

Does your text have anything to do with Australia?
If this is the case, "AHD" could possibly mean meters above sea level.
http://en.wikipedia.org/wiki/Australian_Height_Datum

18:34 Oct 22, 2011 

I found "top of well casing" for TOWC, but we'd need more context to know if that's correct or not.
http://www.lm.doe.gov/cercla/documents/rockyflats_docs/SW/SW...