My husband and I have 20 acres land which we intend to build on sometime soon. The neighbor is having to drill a new well which will feed two houses, and will be drilled approximately 30 - 60 feet or less from the property line. He has called to say that he would like to have us sign an agreement saying that we will not put a septic system within 100 feet of the well head, and upon our saying yes, the neighbor said he would get an agreement drawn up on a future date and go ahead with his drilling. We said no, let's just get together within a few days and get one signed before he begins so that no one is compromised. Based on the former information, (1) isn't it standard in Washington State law that one can't put a septic within 100 feet of any well anyway, and isn't it standardly written into any real estate sales contract? (2) Does it matter as we wouldn't be dumb enough to put a septic so close to a well anyway? (3) Is an agreement like this a wise choice, and what should it contain? I am concerned because, so far, he has had very little common sense concerning his development choices. Thank you for your advice.