Established in 1972, Protanic began by pioneering petroleum leak detection at service stations. Co-founded by engineers William Purpora and Dave Beets, the company's journey shaped the industry. In the 70s, the industry lacked any regulations or protocols governing tank and line leak detection, yet William’s relentless drive for proper leak detection methods and training set the groundwork for Protanic's success.

Following William Purpora's departure, his son Stephen Purpora took the helm as President of Protanic Inc. Over three decades of service and consulting in the petroleum industry shaped Stephen into an industry expert. Stephen's contributions extended beyond Protanic, as he served on multiple Petroleum Equipment Institute (PEI) committees on Recommended Practices, co-authored the recommended practices manual, which is the industry standard for testing, and consulted for the EPA.

In June 2021, Stenstrom Petroleum Services Group acquired Protanic and Purpora Engineering, marking a new chapter for the company. As part of the Stenstrom petroleum family of businesses, Protanic proudly serves as its compliance division. With a well-established reputation as a market leader in fueling system service, repair, and construction across Illinois, Wisconsin, and Iowa, Stenstrom Petroleum caters to industrial, commercial, and retail sectors.


From the early years to today

Key Customers

Protanic is the oldest compliance testing company in the USA. If some of the world's most esteemed companies trust us, why wouldn’t you?

Food 4 Less



kwik trip



Ricky Rockets

Road Ranger

The Pride Stores



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