Some oil industry contractors strive to build a diverse customer base to mitigate the risk of over-reliance on one particular client. At Schlomka’s Vac Truck Service Inc. in Hastings, Minnesota, co-owners Donny and Susan Schlomka take a different tack on diversity: The company offers a small core group of clients — two oil refineries and two pipeline companies — a wide array of different services.As such, Schlomka’s does work ranging from hazardous and nonhazardous waste hauling, industrial vacuuming and hydroexcavating, to pressure washing, drainline cleaning and stormwater pumping. In short, the Schlomkas do pretty much everything but turn out the
