The environmental impact of a construction project can best be summed up as to the amount of damage which could occur if,
a. there is dust
b. there is sediment runoff into streams.
c. the location of the project does not hamper fish migration such as in the middle of a stream.
d. if you are doing damage how does this effect the future of the air or streams. (some minor replacable stuff is allowed such as the minor destruction of a wetland if you replace it twofold.
These are things to initially think about since they are generally the main concerns, but if in the dessert do you destroy catus, etc.
Keep in mind that environmental concerns are justifiable and we all share this planet. Try your best to minimize them or improve such as creating a miniwetland in a storm water management pond and redirecting the upstream runoff from an existing impervious site through your pond.
I have learned through experience that the reviewers are generally knowlegable about this stuff (although some you wonder about)and if you make an honest effort to control and/or improve, (volunterr some new ideas also) some times tradeoffs will be rewarded which would otherwise prevent the project from being approved.
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