co2 in the gunnedah - open file well reports

As I said in a post yesterday, it suddenly occurred to me that while we've been debating gas composition and permeabilities of ESG's coal, much of the information has been sitting around publicly available the whole time.

Specifically, wells drilled prior to 2008 are available open-file on DIGS, the NSW mines department database, at:

http://digsopen.minerals.nsw.gov.au/

Using this database I was able to find the first CSG well drilled in PEL 238, Jacks Creek 1, drilled in 2000. Earlier wells were drilled in what was then PEL 238 but is now PAL 2.

Quote from the report: "Analysis of desorption samples confirmed the wellsite observations that the gas content was predominantly CO2."

You can also check out the Bohena 2 well completion report (PAL 2) which shows gas compositions of 5-15% CO2 (disregarding air contamination), which is better and is commercial but too high to feed into the GLNG pipeline unless processed.

I'm not going to go over them all as anybody interested can look them up themselves by searching PEL 238. But there is definitely a CO2 issue in the Gunnedah - even the areas they choose for pilots have up to 15% CO2.

I had a brief look at total gas contents too and they look pretty good, comparable to Surat coals at equivalent depth. But CO2 in the Surat is unheard of.