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ASSET RETIREMENT OBLIGATIONS (ARO) (Tables)
 9 Months Ended
Jun. 30, 2011
Asset Retirement Obligation Disclosure [Abstract]  
Schedule of Change in Asset Retirement Obligation [Table Text Block]
The following is an analysis of the change in the ARO liability:
(Thousands)
June 30, 2011
 
September 30, 2010
Balance at October 1
$
26,009


 
$
25,097


Accretion
1,242


 
1,572


Additions
—


 
149


Retirements
(711
)
 
(809
)
Balance at period end
$
26,540


 
$
26,009