Thanks for the help, everyone! It has given me some different ways to go about approaching him. We really DO need to add on, on the back of the house - but I have been so frustrated with the constant undulating noise and vibration, I have been ready to pack up and leave. We are in an older home on a long thin, pie shaped lakeshore property, and his house is 40 feet or so from ours. (The bulk of our property runs the length, not the lakeshore "width".) But, I can hear that pump all over the neighborhood. Since lakeshore property has become scarce, my husband NEVER wants to move...so we have to do something proactive. Thank you!!