I have been working on a mod for Fallout: New Vegas. It adds a new cell that is the shooting range from Hidden Valley with some extra additions (melee targets, containers). Everything other than statics, containers, sounds, and lights have been removed. However, when I completed the mod and loaded it in the game, I got intense lag. I have tried multiple times to fix things that may have been causing it, but it is still lagging the same way. How can I fix this problem?

Update: Now I attempted just adding everything to the area nearby an abandoned house way down the road going past the gas station in Goodsprings, and now it has the same lag whenever I am in Goodsprings. It seems that any place that I change at all starts lagging like crazy.

Lag in an interior cell is strange. Did you change the cell after you loaded the mod once or does it lag even with a new fresh game ?
Best would be to post the mod so others can test it and see if it does the same on all systems. Perhaps it is something happening in your own game only.