SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	Sep. 30, 2012	Sep. 30, 2011
Revenue by segment
Percentage of revenue by segment	100.00%	100.00%
Minerals and materials [Member]
Revenue by segment
Percentage of revenue by segment	51.00%	50.00%
Environmental [Member]
Revenue by segment
Percentage of revenue by segment	23.00%	28.00%
Oilfield services [Member]
Revenue by segment
Percentage of revenue by segment	25.00%	20.00%
Transportation [Member]
Revenue by segment
Percentage of revenue by segment	4.00%	6.00%
Intersegment sales [Member]
Revenue by segment
Percentage of revenue by segment	(3.00%)	(4.00%)