The DES appears to have a very loose standard. I know of many camps on the lake whose shower, sink, washer water drains into a dry well and the water eventually drains into the lake. The reason the owners get away with it is that DES normally puts the die in toilets. Toilets waste are usually treated through a septic system and thus pass. I know of a number of camps that use the old out house method.
So the dry well water has mega soap chemicals and it gets into the lake.
Bear Islander's castile soap may be legit, but I know someone on Glidden Cove who got fined for showering next to the lake with this soap. So what gives?