greenhouse gases

so i haven't felt so drained and semi-stressed out from work stuff until this week, or rather, i don't remember the last time i felt this way until this week. i've completed the draft initial study for this in-house storm drain project. but, since this bill was passed by our governor (assembly bill 32), which requires the california air resources board (carb) to establish guidelines to reduce greenhouse gas emissions to 1990 levels by the year 2020, greenhouse gases have the potential to cause significant environmental impacts and require analysis under ceqa. so i had to address greenhouse gases in my initial study. i've spent about 3 months researching/writing the analysis for the greenhouse gas stuff and now, i think i'm finally done...with the draft! i've been tense this week because i felt that i've been spending way too much time on it. but i think what i have now is the best i can do with the information i have. and i am almost sick of it:

Unlike the analysis of criteria pollutants, the analysis of greenhouse gases (GHG) is based on GHG effects that occur over a time frame longer than a single day. The identified GHGs consist of carbon dioxide (CO₂), methane, nitrous oxide, sulfur hexafluoride, hydroflurocarbons, and perflurocarbons. CO₂ has been identified as the most common GHG generated by human activity. The only potential source of CO₂ would result from construction related activities. Construction of the proposed project would result in an estimated GHG emission of 36.9 MTCO_2eq for 2010. Subsequent emissions associated with maintenance activities is expected to be far less than the 2010 construction emissions.

Current available GHG significance thresholds include those proposed by the California Air Resources Board (CARB) in the draft “Recommended Approaches for Setting Interim Significance Thresholds for Greenhouse Gases under the California Environmental Quality Act” (October 24, 2008) and the South Coast Air Quality Management District (SCAQMD) in the “Draft Guidance Document – Interim CEQA Greenhouse Gas (GHG) Significance Threshold” (October 2008). CARB proposes a quantitative GHG threshold of 7,000 MTCO_2eq of operational GHG emissions per year for industrial sector projects. The SCAQMD proposes a quantitative GHG threshold of 10,000 MTCO_2eq for construction emissions amortized over 30 years added to operational GHG emissions per year for industrial sector projects. For residential/commercial sector projects, SCAQMD proposes a quantitative GHG threshold of 3,000 MTCO_2eq for construction emissions amortized over 30 years added to operational GHG emissions per year. The estimated 2010 GHG emission for the proposed project and proposed GHG thresholds are summarized in Table 2: Estimated GHG Emissions for 2010 and Proposed GHG Significance Thresholds.

Table 2: Estimated GHG Emissions for 2010 and Proposed GHG Significance Thresholds

GHG	Project Estimated Construction GHG Emissions for 2010 (MTCO2eq)	CARB Proposed GHG Threshold for Industrial Sector Projects1 (MTCO2eq/year )	Project Estimated Amortized Construction Emissions2 (MTCO2eq/year )	SCAQMD Proposed GHG Threshold for Industrial Sector Projects3 (MTCO2eq/year )	SCAQMD Proposed GHG Threshold for Residential/ Commercial Sector Projects4 (MTCO2eq/year )
CO2	36.9	7,000	1.23	10,000	3,00

1. Threshold applies to operational emissions.

2. Project Estimated Amortized Construction Emissions = Project Estimated Construction GHG Emissions for 2010/30 years = 36.9/30 = 1.23.

3. Threshold applies to construction emissions amortized over 30 years added to operational GHG emissions.

4. Threshold applies to construction emissions amortized over 30 years added to operational GHG emissions.

CARB’s proposed GHG Threshold for operational emissions does not apply to the estimated construction GHG emissions. The estimated amortized construction emission of 1.23 is below SCAQMD’s proposed GHG significance threshold for industrial and residential/commercial sector projects. Thus, potential GHG effects resulting from the proposed project are not cumulatively considerable.

i don't know how many times i've revised this thing. this is only a portion of the entire analysis, but i thought it blog worthy enough to post the portion that i've been sluggishly working on. i am pretty proud.