Page 56 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

LEED Sustainable Sites 37

sedimentation control standards and codes, whichever is more stringent. The Plan shall
describe the measures implemented to accomplish the following objectives:
• Prevent loss of soil during construction by stormwater runoff and/or wind erosion,
including protecting topsoil by stockpiling for reuse.
• Prevent sedimentation of storm sewer or receiving streams.
• Prevent polluting the air with dust and particulate matter.

The Construction General Permit (CGP) outlines the provisions necessary to comply with
Phase I and Phase II of the National Pollutant Discharge Elimination System (NPDES)
program. While the CGP only applies to construction sites greater than 1 acre, the requirements
are applied to all projects for the purposes of this prerequisite. Information on the EPA CGP
is available at http://cfpub.epa.gov/npdes/stormwater/cgp.cfm.

Potential Technologies and Strategies
Create an Erosion and Sedimentation Control Plan during the design phase of the project.
Consider employing strategies such as temporary and permanent seeding, mulching, earth
dikes, silt fencing, sediment traps and sediment basins.

Calculations and Considerations
This strategy for construction phases of projects was commonly referred to as SEC (soil
and erosion control) and now is more commonly known as ESC (erosion and sedimentation
control). The current LEED-NC 2009 requirement is based on the USEPA Construction
General Permit (CGP), for which information is available at http://cfpub.epa.gov/
npdes/stormwater/cgp.cfm. It separates the practices into two overlapping categories,
one for the prevention of erosion (stabilization) and the other for the containment or
control of eroded sediment to other parts of the site or off-site. Some of the common
stabilization methods used include the installation of geotextiles, temporary or permanent
seeding or mulching on exposed soils, and installation of a construction vehicle drive.
Typical sediment control measures include installation of silt fencing downslope of
graded areas, installation of silt barriers around catch basins and other inlets to storm
sewers or waterway access points, and installation of sedimentation ponds. The methods
used are sometimes referred to as structural for actual items installed or nonstructural for
other types of practices, such as scheduling grading activities during a drier season.
The steps for compliance for this credit include having and implementing an ESC
Plan. Many of the structural and nonstructural measures used for ESC will be part of the
project drawings. These project drawings will usually show the location of the methods
on the site plans, list a material schedule for the measures, and include a time schedule for
implementation, maintenance, and, if appropriate, removal of the control measure. The
ESC Plan and this prerequisite adherence also apply to the demolition phase of the project
and to the full extent of the construction, even areas outside of the LEED boundary.
The submittals for the credit include copies of the applicable project drawings and
specifications addressing ESC, a statement as to whether the project adheres to the
national EPA criteria or a stricter local standard, and a narrative outlining the ESC
methods implemented. When a local standard is used, it must be demonstrated in the
narrative that it is at least as strict as the NPDES standard. There are no required
calculations for this credit other than those that might be necessary to verify that the
ESC Plan adheres to the minimum standards required. The submittal is part of the
LEED Construction Submittal, as most of the items are a part of the construction phase
and adherence to the requirements should be documented.