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ASSET RETIREMENT OBLIGATIONS (Details 1) - USD ($)
3 Months Ended 12 Months Ended
Oct. 31, 2017
Jul. 31, 2017
Assumptions Used For ARO Estimates [Line Items]    
Undiscounted amount of estimated cash flows $ 7,275,504 $ 7,098,581
Minimum [Member]    
Assumptions Used For ARO Estimates [Line Items]    
Payable in years 5 years 5 years
Inflation rate 1.37% 1.37%
Discount rate 5.48% 5.48%
Maximum [Member]    
Assumptions Used For ARO Estimates [Line Items]    
Payable in years 17 years 17 years
Inflation rate 2.14% 2.14%
Discount rate 6.40% 6.40%