I am interested in any case studies, reports or information concerning the corrosion resistant capabilites of stainless steel 304 in soil and groundwater conditions.
I used to drill water wells (one of the jobs I've held that compelled me to become an engineer - I didn't want to do that the rest of my life) we always used SS screens in the wells. The companies that make these screens MUST have data that would supply the answers you are looking for.
I would contact a screen manufacturer and ask them to help.
Unless you put your SS in some wet, salty ground, there should be little problem.
Here are some favorite SS info sources. All except ASTM are free:
For stainless steel, the Nickel Development Institute is a great source of free information (375 technical papers!)
You need to check for microbial activity in the soil or groundwater. Stainless steel well casing and screen may be subject to microbially induced corrosion.
Sulphate reducing bacteria will pit SS fairly rapidly. Volcanic soils can also be a problem. Elec conductivity and the presence or potential for stray current from earthing systems should be evaluated.