SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

9 Months Ended

Sep. 30, 2012

Summary of Significant Accounting Policies / Additional Balance Sheet Information [Abstract]

Revenue by segment

The composition of our revenues by segment is as follows:

	Nine Months Ended September 30,
	2012			2011
Minerals and materials		51	%		50	%
Environmental		23	%		28	%
Oilfield services		25	%		20	%
Transportation		4	%		6	%
Intersegment sales		-3	%		-4	%
		100	%		100	%