Having personally walked the subject lands with an Ecologist we both determined that all but one area was an Area of Concern and should be further investigated. This small area ( less than 2 ac)  area was well represented by ecologically significant species and could easily become part of a natural attraction for the development.
The other areas showed no evidence of any species at risk or ecological sensitive zones.  These areas were probably dried up  as a result of municipal drainage.
One could easily set aside a 10 ac parcel and do an amazing wetland restoration project with achievable success .
Further studies would be warranted to determine the full extent of any environmental impacts.