One Rock Capital Partners has agreed to sell EnviroServe, a Cleveland-based provider of environmental and waste management services, to Clean Harbors, Inc for $470 million. The transaction is expected to close in the second half of 2026.

EnviroServe serves customers across a wide variety of end markets from a strategic network of branches, including 10-day transfer facilities, waste solidification facilities and railcar cleaning locations. EnviroServe was founded in 1990.

"We acquired EnviroServe, a high-quality, people-driven business with a strong team, loyal customers and attractive growth opportunities, through a carve-out from Savage Companies and built it into a successful standalone business," said Tony W. Lee, managing partner at One Rock in a statement. "Under our ownership, we have expanded EnviroServe's service capabilities through organic growth, new greenfield locations and add-on acquisitions."

The deal represents continued consolidation in the environmental services sector, with Clean Harbors expanding its footprint through strategic acquisitions.