Smell of sewer gas within cellar-we enjoy a septic cistern?

What is the oldest item contained by your...
first, do you also have propane or raw gas? if so, you may have a gas leak. otherwise, you any have a plugged vent, or a leak.
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also pour some white vinegar down into your septic cistern, it will speed up the process as well as stopping smells

Lava light started to burn?
As Larry said in his answer, it sounds like your traps don't own any water in them. As hose flows out of your house, it travels through a pipe with a "U"-shaped dip in it (look beneath your sink for an example). Water is "trapped" in the bottom of the "U" which blocks the sewer gases and keep them from entering your house. If the drain has not been used within a long time, the water may have evaporated completely allowing the smell to enter your house.
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I've not see many septic houses with floor drains, but if you hold them, keep the traps full.

A more likely culprit after a ooze, would be a broken or disconnected vent pipe.

You could also have gotten some nasty stuff within your sump well or your laundry pump chamber..
How much does replacing a school's pipes costs?
Answers:    Dump some water in your floor drains. The traps might own dried up.