Last week, AIS successfully performed a hydraulic lube oil service on a 4,500 gallon oil reservoir at a manufacturing facility. The customer was complaining of erratically clogging filters and inconsistency in the performance of the unit. The AIS team evacuated the oil from the reservoir into temporary tanks and purified the oil to remove all of the water and hard particulate contamination. We then performed a confined space entry and cleaned the interior of the tank. We found pockets of sludge in the tank as well as various foreign objects. After the cleaning we pumped the oil into the reservoir and filtered the oil down to a 16/14/11 ISO cleanliness code.