Apparatus in fluid communication with a water leg portion of a hydrocarbon-contaminated water, e.g., a water leg portion of an offshore drilling or production platform sump tank for conveying water, separated from oil, into contact with organophilic media canisters such that the hydrocarbons and other organic materials commingled with the sump tank water will be adsorbed onto the organophilic media and detected by the embedded probe in selected canisters. The canisters are provided in a plurality of stacks and are in fluid communication with a header disposed at the bottom of the vessel housing the various stacks of canisters. Solids that do not pass through the canisters are accumulated at the bottom of the vessel and easily drained through a drain port. The water will pass through the media and will be conveyed back to the ocean water without contamination. At some point in time, the organophilic media will become "spent" and at a certain "spent level", the saturated condition of the organomedia will be electronically detected by the embedded probe and alarm/control panel. The alarm indicates that the "spent" organophilic media should be replaced with fresh media or the spent media regenerated.