I went to my basement and I discovered a rotten egg smell in the area near my sump pump. The sump only takes away ground water and is not part of a septic system. At first I thought it was a gas leak, however the gas company came out and could not find a leak. Is it possible that the sump is causing the smell. I have smelled what a dead rodent smelled like and it was significantly worse and substantially different (this may be wishful thinking on my part) thanks for any help.

Have you a floor drain that hasn't seen use lately? Tom

Rotten Egg smell

No. My soil line and all the plumbing taking water out of the house is in the front of the house. The sump pump is in the back corner of my home and has a french drain attached to it. I have had the system for 8-9 years and never experienced this smell before. Over the weekend I opened the sump pump drum and poured one gallon of Clorox. The smell seemed to go away for several hours but as of last night it is back. I have contacted several waterproofing companys and the only suggestion I received is the Clorox.

Smells and noises are the hardest to track down if you're not on site. Having said that let me make a guess.
This could be bacteria growth in the pit or the line leading to the french drain. Click on; EXPEL Odor Neutralizer To find Expel. This is a odor neutralizer that uses Chlorine Oxide as its main ingredient. This is about all I can suggest. Try to kill the bacteria and see if the smell doesn't go away. Regards, Tom