The McMullen name needs to be large, prominent, and legible.  Our colors are bright green and dark green.  The last designer told me the green we used was OOFFOO.  It doesn't have to include a septic truck, but if so, no cartoonish ones.  Possibly a bright green septic pumping hose can be used somewhere (like the border, wrap, or swooshing around it).  No poop on the design please!  If you don't like these feel free to put your own spin it.  Nothing too plain please.  Look at my reference logos that I picked.

McMullen Septic Service