The PPM does not advise composting coffee grounds. Rather, it advises drying the grounds and, once they are dry and granular, simply broadcast spreading them about any green space. The PPM has as a goal the most benefit with the least work and does not understand why a material such as coffee grounds, which when dried is readily assimilatable by the Earth, should be composted. What is wrong with simply spreading it around? I mean, why do the extra work of adding it to a pile?