A brown field is an abandoned industrial site that just sits idle in some of our urban centers. And people are willing to invest capital in the brown fields don't want to do so for fear of lawsuit. I think we ought to have federal liability protection, depending upon whether or not standards have been met.
A brown field was used once for something quite productive
Industry is productive by nature, system assumes otherwise
( z0 use :ARG1 ( z1 field :ARG1-of ( z2 brown ) ) :ARG2 ( z3 something :ARG0-of ( z4 productive :degree ( z5 quite ) ) ) :time ( z6 once ) )
(z0 / use-01
    :ARG1 (z1 / field
              :ARG1-of (z2 / brown-01))
    :ARG2 (z3 / something
              :ARG0-of (z4 / productive-03
                           :degree (z5 / quite)))
    :time (z6 / once))
A brown field was used once for something quite productive
z1 :ARG1-of z2
z0 :ARG1 z1
z0 :time z6
z0 :ARG2 z3
z4 :degree z5
z3 :ARG0-of z4