Final FONSI and EA for hot cargo pad on Kirtland AFB - Kirtland Air ...

<strong>Final</strong> <strong>EA</strong> Addressing Construction, Operation, <strong>and</strong> Maintenance of a Hot Cargo Pad
Control storm water volume <strong>and</strong> velocity to minimize erosion
Control storm water discharges including both peak flow rates <strong>and</strong> total storm water volume
Minimize the amount of soil exposed during construction activities
Minimize the disturbance of steep slopes
Minimize sediment discharges from the site using controls that address factors such as the
amount, frequency, intensity <strong>and</strong> duration of precipitation; the nature of resulting storm water
runoff; <strong>and</strong> soil characteristics, including the range of soil particle sizes expected to be present on
the site
Provide <strong>and</strong> maintain natural buffers around surface waters, direct storm water to vegetated areas
to increase sediment removal <strong>and</strong> maximize storm water infiltration where feasible
Minimize erosion at outlets <strong>and</strong> downstream channel <strong>and</strong> stream bank erosion
Minimize soil compaction <strong>and</strong> preserve topsoil where feasible.
In addition, construction site owners <strong>and</strong> operators that disturb one or more acres of l<strong>and</strong> are required to
use BMPs to ensure that soil disturbed during construction activities does not pollute nearby water bodies.
Effective August 1, 2011, construction activities disturbing a total of 20 or more acres at one time,
including non-contiguous l<strong>and</strong> disturbances that take place at the same time <strong>and</strong> are part of a larger
common plan of development, must comply with the numeric effluent limitation <strong>for</strong> turbidity in addition
to the non-numeric effluent limitations. The maximum daily turbidity limitation will be
280 nephelometric turbidity units.
Section 438 of the Energy Independence <strong>and</strong> Security Act (EISA) (42 U.S.C. 17094) establishes into law
new storm water design requirements <strong>for</strong> Federal construction projects that disturb a footprint of greater
than 5,000 square feet of l<strong>and</strong>. EISA Section 438 requirements are independent of storm water
requirements under the CWA. The project footprint consists of all horizontal hard surfaces <strong>and</strong> disturbed
areas associated with project development. Under these requirements, predevelopment site hydrology
must be maintained or restored to the maximum extent technically feasible with respect to temperature,
rate, volume, <strong>and</strong> duration of flow. Predevelopment hydrology shall be modeled or calculated using
recognized tools <strong>and</strong> must include site-specific factors such as soil type, ground cover, <strong>and</strong> ground slope.
Site design shall incorporate storm water retention <strong>and</strong> reuse technologies such as bioretention areas,
permeable pavements, cisterns/recycling, <strong>and</strong> green roofs to the maximum extent technically feasible.
Post-construction analyses shall be conducted to evaluate the effectiveness of the as-built storm water
reduction features. As stated in a DOD memor<strong>and</strong>um dated January 19, 2010, these regulations will be
incorporated into applicable DOD Unified Facilities Criteria (UFC) within 6 months (DOD 2010).
Additional guidance is provided in the USEPA’s Technical Guidance on Implementing the Stormwater
Runoff Requirements <strong>for</strong> Federal Projects under Section 438 of the Energy Independence <strong>and</strong> Security
Act.
Floodplains are areas of low-level ground present along rivers, stream channels, or coastal waters that are
subject to periodic or infrequent inundation due to rain or melting snow. Floodplain ecosystem functions
include natural moderation of floods, flood storage <strong>and</strong> conveyance, groundwater recharge, nutrient
cycling, water quality maintenance, <strong>and</strong> habitat <strong>for</strong> a diversity of plants <strong>and</strong> animals. Flood potential is
evaluated by the Federal Emergency Management Agency (FEMA), which defines the 100-year
floodplain as an area within which there is a 1 percent chance of inundation by a flood event in a given
year. Risk of flooding is influenced by local topography, the frequency of precipitation events, the size of
the watershed above the floodplain, <strong>and</strong> upstream development. Federal, state, <strong>and</strong> local regulations often
Kirtl<strong>and</strong> AFB, NM January 2011
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