Harris Williams & Co., a middle-market investment bank focused on the advisory needs of clients worldwide, announced the sale of QualaWash Holdings, a provider of environmental services to the bulk transportation industry, to Roark Capital Group.

QualaWash was a portfolio company of KLH Capital (KLH). Harris Williams & Co. acted as the exclusive advisor to QualaWash. The transaction closed on June 29, 2012 and was led by John Neuner, Brian Lucas, Luke Semple and Marshall Croft from the firm’s Richmond office.

“Since acquiring QualaWash, KLH and management have executed a very successful growth strategy that through several strategic acquisitions and the addition of several service lines has enabled the company to become the only nationwide, independent provider capable of servicing a complete line of tank trailers, ISO containers and intermediate bulk containers,” said John Neuner, a managing director at Harris Williams & Co. “QualaWash’s management team is looking forward to continuing to execute on their growth plans, and we are pleased to have found them a great partner in Roark, who has extensive experience growing businesses in the environmental services sector. This transaction represents an incredible partnership and is a great outcome for all parties involved.”

The industrial and environmental services sector has been a significant focus for Harris Williams & Co. Over the past few years, Harris Williams & Co.’s clients in this sector have served a broad range of end markets, and include PSSI, which provides services to the food processing industry; Grand Isle Shipyard Inc., which provides critical services to the offshore and onshore oil and gas industry; and Philadelphia Gear Corporation, which serves the industrial, power generation, oil and gas, infrastructure and military marine industries.

QualaWash is a privately owned bulk transportation services provider operating in 52 locations nationwide. With 550 dedicated professionals, QualaWash is one of North America’s largest providers of container cleaning, depot and reconditioning services. Originally founded in 1940, QualaWash grew organically and through multiple acquisitions to establish the industry’s only independent, nationwide network.

KLH is a Tampa-based private investment firm founded to provide entrepreneurs with capital to facilitate recapitalizations, management buyouts and buy-ins, family successions and other ownership transitions.

Roark is a private equity firm that specializes in franchise, brand management, environmental services and marketing services companies with attractive growth prospects.