Multilevel Environmental Impact Analysis - Environmental Impact Analysis: Process and Methods - page 248

past actions and included commitments to the following practices as prudent
and practical impact mitigation measures:
r Qualified personnel will conduct a detailed surface runoff impact
study of the proposed construction area, including calculation and
evaluation of both current and proposed land drainage contours
and impervious surfaces (e.g., roof and asphalt).
r The results of the study will be used to determine impact on both
man-made and natural storm water conveyance systems.
r Where impacts are predicted, recommendations will be imple-
mented to preclude or mitigate that impact.
The analysis of impacts was treated similarly in the programmatic EA for
the other environmental resources and activities.
The programmatic EA concluded that based on the environmental impact
analysis conducted, the findings of relevant EAs previously prepared, and
the incorporation of required mitigation, the proposed action would not
result in significant environmental impacts to any resource, and so a FONSI
was issued. Thus, an EIS was not necessary and future individual projects
and actions consistent with the statement of purpose and need and descrip-
tion of the proposed action in the programmatic EA could proceed without
separate and project-specific NEPA documentation.
As discussed above, the conclusions of the programmatic EA were based
on adherence to certain standardized procedures and compliance with envi-
ronmental regulations and permits. The EA also included a list of 30 required
best management practices including construction procedures such as:
r Vegetative ground cover shall not be destroyed, removed, or dis-
turbed more than 15 calendar days prior to grading.
r A floating sediment boom shall be placed downstream of the con-
struction area to collect the unsettled silt or debris. The device shall
be cleaned and maintained on a daily basis.
r Construction must be sequenced to minimize the exposure time of
cleared surface areas.
r Grading activities must be avoided during periods of highly erosive
rainfall.
r All surface water flowing toward the construction area shall be
diverted around the construction area to reduce its erosion potential
using dikes, berms, channels, or sediment traps as necessary.
r Temporary diversion channels must be lined to the expected high water
level and protected by non-erodible material to minimize erosion.
r Clean rock, log, sandbag, or straw bale check dams shall be properly
constructed to detain runoff and trap sediment.