Two alternative treatment trains are being considered. Train 1 includes three treatment processes, each of which, when operating References 221 normally, reduces the target pathogen by two orders of magnitude (a 2 log reduction). Train 2 includes four independent unit processes in series. Two of the processes reduce the target pathogen by two orders of magnitude (a 2 log reduction) Each of the other two processes reduce the target pathogen by one order of magnitude (a 1 log reduction in each step). If each of the seven unit processes listed above fails to perform, at random, about one percent of the time and if, when a unit process fails, the removal it achieves is half of what it normally achieves, estimate: (a) the overall removal for trains 1 and 2 when all the unit processes are operating normally and (b) for each train the frequency (in days per year) of various levels of removal assuming that process failures occur randomly.