Effluent was ponding in the outdated, overused drainfield of a 44-unit mobile home park in Allegan, Mich., and raw sewage flowed into a swamp forest draining into Swan Lake. The owner called maintenance provider Rod Carroll of Wray’s Septic Tank Co. in Allegan to pump the 20,000-gallon septic tank twice a year until health officials gave him an ultimatum to replace the system in three months.Wray’s won the bid, and Carroll worked with Randy Rapp, P.E., of Exxel Engineering Inc. in Grand Rapids, to design the system. “We had no room for a replacement drainfield, but the septic code allowed
