|Trees and the Chevron Energy and Hydrogen
January 27, 2008
The word “tree” is not mentioned even once in the 1,355 pages (excluding appendices) of the Chevron Energy and Hydrogen Renewal Project DEIR and FER in the context of a potential mitigation for greenhouse gases or any other impact, including visual impacts. The closest thing is a fact associated with a summary of Issues & Opportunities Paper #8: Community Health and Wellness in the FEIR, page 2-55:
Most urban areas in Richmond have low tree coverage … Only about 10% of Richmond has tree canopy (more than 25% tree coverage), compared to 42% in Portland and 21% in the nation.
Despite no discussion of the potential of trees to mitigate impacts of the project, the Richmond Planning Department suggested the following in the Design Review staff report:
However, staff is recommending the planting of a buffer of Coastal [sic] Redwoods around the refinery perimeter to provide partial screening of the equipment from view, and supports planting a sufficient number of trees within certain areas of Richmond to screen, as much as possible, the refinery from view. If planted in enough of a quantity, the trees will also offset greenhouse gas emissions to a measurable level.
Without any evaluation or analysis in the DEIR and FER, I was curious what would constitute a measurable level of greenhouse gas emission offset.
A little research, however, reveals that it may not be that simple. No one disagrees that trees absorb CO2, but how much is the subject of differing opinions. And some say that planting trees in temperate climate zones, such as Richmond, may actually contribute to global warming.
I reviewed about 20 different sources I found on the Internet using Google. Several sources estimated CO2 absorption rates in the range of about 4 to 6 metric tons a year per hectare. A metric ton is 1,000 kilograms, and an acre equals 0.40 hectare. Using a mid range of 5 metric tons per hectare is equivalent to12.5 metric tons per acre. Various sources rate the CO2 absorption of a single tree from as low as 7.5 kilograms to as high as 650 kilograms a year.
According to the DEIR, Chevron’s total greenhouse emissions are 2.7 million metric tons per year, with 0.9 million resulting from the proposed project. To put that in perspective, it would take 180,000 acres of trees to consume the greenhouse gas from the proposed project and 540,000 acres, or 844 square miles to consume the total greenhouse gases emitted from the refinery post-completion. For comparison, Contra Costa County is 720 square miles.
In addition to greenhouse gases produced in the refining process, the completed project will be part of a refinery that produces fuel which, when combusted, will also produce greenhouse gases. The Chevron Refinery can produce about 13,584 barrels per day of product, mostly fuels. That’s 570,566 gallons of product per day, or about 208 million gallons per year. Each gallon of gasoline, which weighs about 6.3 pounds, could produce 20 pounds of carbon dioxide (CO2) when burned. That’s about 2 million metric tons of greenhouse gas annually. Using the same figures, it would take 160,000 acres to absorb the CO2 from vehicles burning the Chevron produced fuels.
Add that all up, and you get 700,000 acres (1,094 square miles) of trees required to offset the greenhouse gases produced directly and indirectly by the Chevron Refinery.
Then there is another Catch 22. “Trees grow three times faster in the tropics than in temperate zones; each tree in the rainy tropics removes about 22 kilograms (50 pounds) of carbon dioxide from the atmosphere each year. However, this study found little to no net global cooling from tree planting in temperate climates, where warming due to sunlight absorption by trees counteracts the global cooling effect of carbon sequestration. Furthermore, this study confirmed earlier findings that reforestation of colder regions — where long periods of snow cover, evergreen trees, and slow sequestration rates prevail — probably results in global warming” (Jha, Alok. "Planting trees to save planet is pointless, say ecologists", The Guardian, 2006-12-15. "To plant forests to mitigate climate change outside of the tropics is a waste of time").
According to Ken Caldeira, a study co-author from the Carnegie Institution:
To plant forests outside of the tropics to mitigate climate change is a waste of time. To prevent climate change, we need to transform our energy system. It is only by transforming our energy system and preserving natural habitat, such as forests, that we can maintain a healthy environment. To prevent climate change, we must focus on effective strategies and not just ‘feel-good’ strategies." 
Tropical rain forest land costs between $5 and $25 per hectare to purchase, so purchasing and protecting 700,000 acres (280,000 hectares) of tropical rain forest would cost only $4.2 million at an average cost of $15 per hectare and totally offset the direct and indirect greenhouse emissions from the Chevron Refinery,
What these studies that concluded temperate forests contribute to global warming did not take account of is the “heat island effect” of urbanization. The models that predicted more warming from trees compared forests to grasslands or snowfields, not urbanized areas. According to the EPA, trees in urban areas are a net benefit:
Increasing the cover of trees and vegetation in a city is a simple and effective way to reduce the urban heat island effect. Trees provide a wide range of other benefits, from increasing property value to reducing storm water runoff.
Shade trees also can make homes and buildings significantly more energy efficient. Scientists estimate that strategically planting trees and vegetation reduces cooling energy consumption by up to 25%. For many, this research comes as no surprise—trees have been used to cool homes for hundreds of years (http://www.epa.gov/heatisland/strategies/index.html).
The term "heat island" refers to urban air and surface temperatures that are higher than nearby rural areas. Many U.S. cities and suburbs have air temperatures up to 10°F (5.6°C) warmer than the surrounding natural land cover.
Heat islands form as cities replace natural land cover with pavement, buildings, and other infrastructure. These changes contribute to higher urban temperatures in a number of ways:
In addition to these factors, heat island intensities depend on an area's weather and climate, proximity to water bodies, and topography. Measuring heat islands can help determine how these factors influence the heat island effect (http://www.epa.gov/heatisland/about/index.html).
There are many other reasons that trees can mitigate direct and indirect impacts in Richmond from the Chevron Energy and Hydrogen Renewal Project.
· Trees and associated plants create local ecosystems that provide habitat and food for birds and animals. They offer suitable mini-climates for other plants that could otherwise be absent from urban areas. Biodiversity is an important part of urban forestry.
· We all know that property that is well landscaped with trees and other plants is more desirable than property sitting on a barren landscape. Studies have shown that:
Tree City USA designation requires, among other things, a budget of $2 per resident dedicated to tree planting and maintenance. At 10%, Richmond has slightly less than one-half the national average tree canopy.
It would be well within the purview of the Design Review Board to require the following conditions of approval, some of which might also be addressed in the CUP, for the Chevron Energy and Hydrogen Renewal Project:
1. $200,000 per year for ten years for a total of $2 million to pay for tree planting and maintenance in Richmond to qualify for Tree City USA designation.
2. Acquisition and protection in perpetuity of 280,000 hectares of tropical rain forest to offset direct and indirect greenhouse gas emissions at a cost not to exceed $4.2 million.
3. Elimination of invasive exotic plants from Refinery property, including broom pampas grass, fennel and eucalyptus.
4. Replacement of flammable and dangerous Monterey pines and eucalyptus in the tank farm area with more fire resistant native oaks and redwoods.
5. Planting of screening trees at the Refinery perimeter, with species and disposition to be determined by further study by expert horticulturists.