Segment Information - Components of Segment Revenues and Adjusted EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting Information [Line Items]
Segment Revenues	$ 130,312	$ 132,578	$ 404,902	$ 402,619
Segment Adjusted EBITDA	18,373	21,487	51,337	59,249
Operating Segments
Segment Reporting Information [Line Items]
Segment Revenues	130,312	132,578	404,902	402,619
Segment Adjusted EBITDA	25,313	29,474	74,163	81,275
Assessment, Permitting and Response | Operating Segments
Segment Reporting Information [Line Items]
Segment Revenues	46,414	63,412	142,051	209,379
Segment Adjusted EBITDA	9,820	15,719	30,252	46,379
Measurement and Analysis | Operating Segments
Segment Reporting Information [Line Items]
Segment Revenues	43,754	38,752	125,739	111,309
Segment Adjusted EBITDA	8,483	8,283	21,852	22,634
Remediation and Reuse | Operating Segments
Segment Reporting Information [Line Items]
Segment Revenues	40,144	30,414	137,112	81,931
Segment Adjusted EBITDA	7,010	5,472	22,059	12,262
Corporate and Other
Segment Reporting Information [Line Items]
Segment Adjusted EBITDA	$ (6,940)	$ (7,987)	$ (22,826)	$ (22,026)