All contaminated soil would have to be removed and bagged.

The costs could vary depending on the contamination.

Would you recommend to buy a lot in Benzene water contamination area to bring the cost down?

A Ton of great information....I've handled mold problems from small basement areas with bleach to full blown remediation jobs and I even headed up a remediation project on a 300 room name brand hotel (all 300 rooms heavily contaminated with black mold).

The big question is there any soil contamination and if there is to what extent.

i don't know how far you'll have to take it, but it might include pulling out carpet and some sheetwork.i would definitely watch out, and determine the extent of contamination.

What happens if your water source becomes contaminated?

I chose a local company, and they were very sensitive working with the family and completely removed all contaminated material.

You don't want to contaminate it in any way because the police need to verify whether foul play was involved.Call 9-1-1 and report the incident.

The most concern I have is regarding soil contamination.