I Posted a while back about my lake being drained 4 ft to put in gas line..Heaven behold they started today and I fished about 4 hours with 2 fish..My question is what kind of impact does letting water down have on bass and how should i target them or just forget about the lake going down and start casting..Any comments would be appreciated

Rapidly falling water is normally tough.  They are probably in panic mode, heading for the deeper spots and only eating what and when they have to.  I'd give it a few days to stabilize and head back out.  (assuming they have drawn the lake down as far as they need to.)  When they get acclimated to the new water level, they should be plenty hungry!  

I would still target the same types of places, if they like wood or brush, stay with it, etc.  I'd guess they will be tight to whatever cover they use for a day or two, it's a security thing.

Last year we experienced a significant drought in this area and some of the lakes were 6 to 8 ft. below full pool maybe dropping the lake down to about 3/4 it's normal size.  On one lake in paticular that we mainly fished the most the fishing was usually good once you located them.  

Bass of all sizes would conjest in weed beds on the remaining flats close to channels and seem to go into feeding frenzies on shad.  Although we didn't always have luck with some of the favorites and even colors when it came to baits, you usually could find something that did the trick.  Some days our numbers ran around 30 or 50 even though the size might range from dinks to 8lbs. from the same spots.

Draining your lake ? Sounds like the perfect time to install some fish attractors.  ;D