not really sure of what the specific issue is but yes, you can do that, just make sure the fabric you use is water permeable you want the ground water to still get through to the tree roots.  

The arena was constructed pretty much all above ground due to flooding and ground water issues.

A Phase I site assessment is a non-intrusive site investigation and does not typically involve the sampling of soil, air, groundwater, and/or building materials.

Above all else make sure you have sweet ground water if in the countryside.  

And the groundwater is incompatible for human consumption due to abandon mines.No utilies, no stores, no police or emergency presence for a good hour, no nothing.

.), existing site conditions (high ground water, site topography, existing soil types and soil environmental concerns, etc.), the location, depth, and capacity of utilities to service the site - including public utilities (sanitary, storm and water services), franchised utilities (power, gas, cable), capacity of the local streets to accommodate additional traffic from your development...Be sure to find out if there are any specific local ordinances you need to satisfy (possible tree & wetland surveys, together with any necessary tree & landscape or wetland mitigation plans) and whether there are any concerns from municipal departments (e.g. hydrant locations from the fire department, storm inlet and retention requirements, as well as asphalt / concrete road requirements from the engineer), entrance requirements from the road commission (left turn and passing lanes at the site entrance), etc.Once you get past all this you can finally prepare a preliminary site plan and enter the political arena to get preliminary site plan approval, and to address any concessions the board and neighbors want from you to overcome their objections to your development.

Assuming the property is in the Denver area, the issue is likely drainage and ground water.

If not in the city, and not in the ETJ, then it's a lot easier, provided you can get water (probably need to drill water wells so thats a separate ground water district) and sanitation (some sort of onsite sewage treatment).

Every Google answer I found was it shouldn’t be done because it can contaminate the soils and groundwater.

Settling in florida is normal because of the sandy soils with high ground water. 2.