Volume 2: Draft Gorst Planned Action Environmental Impact Statement

Gorst Planned Action EIS | AppendicesAppendix CDerivation of Development Emission Reduction FactorsVMT and greenhouse gas emission rates generated by vehicle travel associated with the Gorst UGA area wereadjusted downward to account for development that will encourage residents and workers to commute optionsother than single-occupancy vehicles. The development reduction factor for each alternative was derived using thescoring system described in the Sacramento Metropolitan Air Quality Management District (SMAQMD) document“Recommended Guidance for Land Use Emission Reductions”, Version 2.5, updated August 15, 2007. Thatdocument presents a wide variety of design features that are typically available for the land use design of anygiven development, and scores the percent reduction in VMT and vehicle emissions by assigning ‘mitigationpoints” to each selected development feature. The numerical value of each “mitigation point” is equivalent to thepercent reduction in VMT and vehicle emissions compared to the base-case land use design. For example, if adeveloper selects a set of development-related features with a cumulative mitigation point total of 10, then it isassumed the VMT and vehicle emissions would be reduced by 10 percent.Note, the development-related mitigation is applied only to emissions generated by vehicle travel. This methoddoes not attempt to evaluate GHG emission reductions from construction materials, electricity usage, spaceheating, or waste reduction.Development Reduction Factor Derivation for AlternativesTable C-1 shows the list of development-related land use features that appear to be inherent in the land use designof the Gorst UGA, and shows the mitigation points assigned to each of those land use features. The key featuresthat are believed to be inherent to the Gorst UGA are as follows:Bicycle paths within ½ mile, with connection to transit.High mixed-use density close to transit.Residential densityThe combined mitigation points for the above features is 4, so the base-case VMT and transportation-related GHGemissions factors for the action alternatives were reduced by four percent, as applied to the per-dwelling factorsand the per-square-foot factors.Note, for this analysis mitigation points were assigned only to the above land use features that are inherent to theoverall programmatic configuration of the Gorst UGA. This analysis did not attempt to predict what other projectspecificdesign features the future developers might build into their facilities, to respond either to encouragementby the City and County or to comply with potential Gorst-specific design standards. It is possible the futuredevelopers could incorporate more of SMAQMD’s listed design features into their facilities, in which case theactual overall development-related reductions might be higher than the four percent value derived for this study.C-1