Appendix
The data and information incorporated into this report reflect the best information available to our knowledge and have been reviewed for accuracy to the best of our ability. Each indicator has been reviewed by the organization(s) supplying the corresponding data. The Silicon Valley Environmental Partnership acknowledges that this is the first environmental indicators report that we have created. As such, it is a living document that will continue to evolve over time as new and improved data become available. We are open to new information that enhances the accuracy of our findings. We welcome your comments.
Introduction (Why Did We Write This Report?)
National survey results are from the 1997 National Report Card on Environmental Knowledge, Attitudes, and Behaviors, published by the National Environmental Education and Training Foundation in Washington, D.C. SVEP defines Silicon Valley as Santa Clara County plus adjacent parts of San Mateo, Alameda, and Santa Cruz counties in Northern California. Specifically, the definition includes: all of Santa Clara County; San Mateo County south of Highway 92; Fremont, Newark, and Union City in Alameda County; and Scotts Valley in Santa Cruz County. With a population of more than 2.3 million people, this region has more residents than 18 of the U.S. states. The indicators in this report reflect this definition of Silicon Valley, except where noted as Santa Clara County or otherwise.
Energy Use Jumps 20% Over 11 Years, Despite Stable Per-Capita Energy Consumption
Quads of energy use were calculated using conversion factors of 125,071.4 BTU per gallon of gasoline, 100,000 BTU per them of natural gas, and 3,413 BTU per kWh of electricity. Information sources used for the analysis include: California Energy Commission and the California Department of Transportation.
Urban Land Use Expands, But Valley Using Urban Land More Efficiently
Land use definitions are from the California Department of Conservation. Urban and Built-Up Land is used for residential, industrial, commercial, construction, institutional, public administrative purposes, railroad yards, cemeteries, airports, golf courses, sanitary landfills, sewage treatment plants, water control structures, and other development purposes. Highways, railroads, and other transportation facilities are included as Urban and Built-Up Land if they are part of a surrounding urban area.
Grazing Land is land on which the existing vegetation, whether grown naturally or through management, is suitable for grazing or browsing of livestock. Agricultural Land includes prime farmland, farmland of statewide importance, unique farmland, and farmland of local importance, as defined by the Department of Conservation. Other Land consists of government lands not available for agricultural use; brush, timber, wetlands, and other lands not suitable for livestock grazing; vacant and nonagricultural land larger than 40 acres in size and surrounded on all sides by urban development; rural development which has a building density of less than 1 structure per 1.5 acres, but with at least 1 structure per 10 acres; confined livestock, poultry, or aquaculture facilities of 10 or more acres unless accounted for by the County's Farmland of Local Importance definition; strip mines, borrow pits, gravel pits, ranch headquarters, or water bodies larger than 10 acres; and a variety of other rural land uses. Protected open space not used for agriculture and restricted from grazing is generally included in Other Land. Water areas 40 acres or larger were excluded from the graph and analysis. Water areas in 1998 were 8,457 acres, or about 1% of Santa Clara County.
The shift in land use from "Grazing" to "Other" between 1996 to 1998 was caused by the following three factors. 1) Grazing leases expired in the Redfern Ranch addition to Henry Coe State Park, causing a large change from Grazing to Other. 2) A few county and state parks previous mapped as Grazing, including Coyote Creek County Park near Morgan Hill, were reclassified as Other. 3) New ranchette development (low density housing) was discovered in the San Jose East quadrangle.
Impervious surfaces refers to land which has been paved over or which otherwise does not allow water to seep through the earth. Information sources used for the analysis include: California Department of Conservation, Division of Land Resource Protection, Farmland Mapping and Monitoring Program; "The Bay Area's Farmlands", Greenbelt Alliance, 1991; and Joint Venture: Silicon Valley Network's 1999 Index of Silicon Valley.
Water Use, After Trending Downward, Increases to Near Pre-Drought Levels
Information about the annual average growth rate in per-capita and total water use from 1991 to 1998 was calculated via linear regression analysis over that time period. Information sources used for the analysis include: Santa Clara Valley Water District; Water Conservation pamphlet, Santa Clara Valley Water District; "Water Plans Pit Farms, Cities", San Jose Mercury News, 5/18/98; "Water Woes in Silicon Valley", San Jose Mercury News, 6/24/98; and Joint Venture: Silicon Valley Network's 1999 Index of Silicon Valley.
Waste Reduction Progress is Threatened by Increases in Waste Disposal
Note that the data for years 1987 to 1994 are slightly different from the data for years 1995 through 1998. The data for years 1987 to 1994 represent the total tons disposed in Santa Clara County regardless of the origin of those tonnages. Tonnages for 1995 to 1998 reflect tons disposed by Santa Clara County jurisdictions at landfills both inside and outside the County. Information sources used for the analysis include Santa Clara County Integrated Waste Management Program.
Population Growth Continues; Three-Quarters Due to Births Outpacing Deaths
Information sources used for the analysis include: California Department of Finance, Demographic Research Unit; "Immigration Question Tears at Environmentalists", San Jose Mercury News, 4/12/98. Fertility rate estimates for Santa Clara County are from the California Department of Health Services, Center for Health Statistics, Office of Health Information & Research. 2.11-2.16 represents the range of the total fertility rate (average number of children born to a woman during her lifetime) for Santa Clara County from 1990 to 1996. 1995 and 1996 total fertility rates are based on preliminary data.
Air Quality Has Improved, but Challenges Remain
The Bay Area Air Quality Management District takes daily measurements of air quality (except PM10 which is monitored once every six days) at monitoring stations throughout Silicon Valley. The graph depicting ozone exceedances reflects the number of days that at least one of these stations exceeds the federal or state standards. The federal standard, at 120 parts per billion, is set to protect the health of the average person, while the stricter state standard, 90 parts per billion, protects the health of persons with respiratory difficulties.
The graph depicting PM10 exceedances shows the number of days in exceedance relative to the total number of days monitored. Exceedances of PM10 are measured against the state 24-hour PM10 standard. PM10 is measured for 24 hour periods once every 6 days.
Information sources used for the analysis include: Bay Area Air Quality Management District; "Environmental Profile for Santa Clara County, California - Air Quality", U.S. Environmental Protection Agency's Center for Environmental Information and Statistics, http://tree2.epa.gov/CEIS/CEIS.NSF/$$All/0606085AIR; Joint Venture: Silicon Valley Network's 1997 Index of Silicon Valley.
Ride-Sharing Helping, But Heavy Dependence on Car Continues
Commute data shown on the graph is generated by RIDES for Bay Area Commuters, Inc., via random telephone surveys. Survey results are statistically valid at the 95% level, with a confidence interval of +/- 5%. This means that 95 times out of 100 the characteristics of the sample would reflect the characteristics of the population, within +/-5%..
Information sources used for the analysis include: Rider Commute Profiles, RIDES for Bay Area Commuters, Inc.; California Department of Transportation, Transportation System Information Program; "Road Building a Dead End for Congestion", San Jose Mercury News, 11/14/98; "Make the Bay a Bridge, Not a Barrier", San Jose Mercury News, 3/30/98; "Auto Addiction", Metro, Santa Clara Valley's Weekly Newspaper, July 27-August 2, 1995.
Carbon Emissions Increase 19% Since 1986 Due to Transportation
The carbon emissions indicator reflects almost all of the carbon emissions in Santa Clara County except emissions from aviation, diesel sources, self-generated industrial sources, and sources not derived from fossil fuels. The sharp increase in electricity-derived carbon emissions during 1994 is because the major electric utility serving Santa Clara County burned the last of its fuel inventory that year.
Information sources used for the analysis include: California Energy Commission; California Department of Transportation; U.S. Department of Energy; Emissions of Greenhouse Gases in the United States, 1995, Energy Information Administration, U.S. Department of Energy, 10/96; State of the World 1996, Worldwatch Institute; Getting the Prices Right: Can Tax Reform Help Both the Economy and the Environment?, Briefing Book, Redefining Progress, 5/21/97; "U.S. Must Lead the Global Warming Battle", San Jose Mercury News, 11/16/98.
Ozone-Depleting Compounds Phase Out as International Treaty Implemented
The graph shows estimated emissions of ozone-depleting compounds from Santa Clara County industry stationary sources, weighted by ozone-depleting potential. Emissions from moving vehicles and other sources are not included. The figures on the graph were calculated by multiplying the pounds of emissions for each compound by its corresponding ozone depleting potential for each year shown, then summed for each year and graphed. The Class I chemicals included are as follows: CFC-11, CFC-12, CFC-113, CC14 (carbon tetrachloride), methyl chloroform, and methyl bromide. The Class II substances included are: HCFC-22, HCFC-123, HCFC-124, HCFC-141, and HCFC-225. Class I substances not included are: CFC-114 and CFC-115 from Group I, Group II (3 halons), and Group III (10 various CFCs including CFC-13, CFC-111, CFC-112, and CFCs 211 through 217).
Information sources used for the analysis include: Bay Area Air Quality Management District; "Gaping Hole Alarms Scientists", San Jose Mercury News, 10/5/96; "Excess Ultraviolet Rays Tied to Amphibian Deaths", San Jose Mercury News, 12/9/97; "Ozone Layer Damage Appears to be Leveling Off", San Jose Mercury News, 10/1/98; "The Black Market Vs. The Ozone", Business Week, 7/7/97; "Protection of the Ozone Layer", U.S. Environmental Protection Agency, http://www.epa.gov/ozone/science/indicat/indicat.html.
Indoor Air Quality Research Needed
Information sources used for the analysis include: "Everyday Exposure to Toxic Pollutants," Scientific American, 2/98; "Mathematical Modeling of Indoor Air Quality", Stanford University Department of Statistics, 7/9/96; "Chip Maker Sued Over Chemicals", San Jose Mercury News, 1/16/99.
Watershed Health in Serious Condition
It is important to note that data used by U.S. Environmental Protection Agency to create this indicator relies on national data sets. As such, it does not include more localized data from states or local sources that could improve the analysis. Subsequent versions of this indicator will incorporate additional and improved data.
Information sources used for the analysis include: The U.S. Environmental Protection Agency's Index of Watershed Indicators website for the Coyote Watershed, http://www.epa.gov/surf2/hucs/18050003/; Stream Care Guide for Santa Clara County, Santa Clara Valley Water District, 1996; Joint Venture: Silicon Valley Network's 1999 Index of Silicon Valley.
Drinking Water Meets or Exceeds Standards; Protection From Contaminants Is Critical
Drinking water is tested after treatment before it enters the distribution system, and it is tested for some parameters in the distribution system. Constituents included in the top graph (showing percent of drinking water analyses in compliance with drinking water standards) are inorganics, nitrates/nitrites, volatile organic compounds (VOCs), and synthetic organic compounds (SOCs). Constituents not included in the top graph are bacteriological tests because the data was not yet available in electronic form.
Maximum Contaminant Levels (MCLs) are the highest level of a contaminant that is allowed in drinking water. They are developed based on toxicological risk calculations to ensure that drinking water does not pose any short-term or long-term health effects. MCLs have been established for most, though not all, of the contaminants found in the South Bay. Such standards are typically based on lifetime exposure for an adult. However, MCLs may not be as protective of sensitive populations such as children and those with immune system disorders. Also, these standards do not explicitly account for the potential synergistic effects between mixtures of chemicals.
In addition to calculating the percentage of drinking water analyses exceeding MCLs (shown in the top graph), we also analyzed the percentage of VOCs and SOCs exceeding the California Department of Health Service's "trigger level", which is typically the detection limit for VOCs and SOCs. Less than 1% of samples exceeded the trigger, ranging from 0.49% to 0.73% during 1994 to 1998.
With respect to the bottom graph (showing population served by Community Water Systems in violation in Santa Clara County), a Community Water System (CWS) is a public water system that supplies water to the same population year-round (e.g., homes or apartments in residential communities, towns, or cities). A public water system is defined as a drinking water system which provides water for human consumption to at least 15 service connections or regularly serves an average of at least 25 people each day at least 60 days per year. Note that CWSs often provide drinking water to consumers in multiple counties. Therefore, the population served by CWSs in Santa Clara County does not necessarily correspond with the population residing in Santa Clara County. Also note that the figures do not represent the level of exposure to or risk from a specific drinking water contaminant. Drinking water contaminants can result in a variety of health effects, depending on the amount of the contaminant(s) ingested, the duration of ingestion, the contaminant's toxicity, and the age and general health of the person(s) exposed. Further, note that the data describes drinking water as it leaves the treatment facility (and the level of lead at some home faucets). It does not precisely contain information about the quality of drinking water at each individual tap. For more information, visit the website http://tree2.epa.gov/ceis/ceis.nsf/$$All/0606085DW (see information sources, below).
Information sources used for the analysis include: California Department of Health Services, Monterey Branch, August 1999; Environmental Profile for Santa Clara County, California, from the Center for Environmental Information and Statistics website, http://tree2.epa.gov/ceis/ceis.nsf/$$All/0606085DW, which depicts data from the U.S. Environmental Protection Agency's Safe Drinking Water Information System; "Discover Water", Santa Clara Valley Water District, 1990; "Indicators For A Sustainable San Mateo County", Sustainable San Mateo County, 1998; "Annual Water Quality Report", Sunnyvale Quarterly Report, 4/98; "Annual Water Quality Report", City of Palo Alto Utilities, 3/15/99; and "Governor Issues Order to Phase Out MTBE", San Jose Mercury News, 3/26/99.
Fuel Leak Cases Drop, But MTBE Shows Up in Water Sources
The motor fuel leak data shown on the graph represents "open" cases (i.e., sites discovered and undergoing clean-up) in Santa Clara County and Scotts Valley (San Martin data is excluded), as tracked in the Leaking Underground Storage Tank Information System (LUSTIS) databases of the San Francisco and Central Coast Regional Water Quality Control Boards (RWQCB). For years 1982-1997, 70 open fuel leak cases are excluded due to insufficient information or data entry errors. The number of hazardous chemical leaks represents active cases in Silicon Valley as of May 1999 from the Spills, Leaks, Investigations, and Clean-Ups (SLIC) databases of the San Francisco and Central Coast RWQCBs.
MTBE has been detected in Santa Clara County's water supplies in concentrations ranging from 0.6 to 2.9 parts per billion (ppb). The California Department of Health Services, Office of Drinking Water has adopted a 5 ppb drinking water standard that protects consumers from unpleasant tastes and odors. In addition, the California Office of Environmental Health Hazard Assessment has adopted a public health goal of 13 ppb MTBE in drinking water to protect consumers against health risks over a lifetime of exposure.
Note that Scotts Valley is excluded from the MTBE monitoring and detection data on the graph because we did not have data from the Central Coast RWQCB on the number of Scotts Valley cases monitoring for MTBE. Also note that because our calculation of open fuel leak cases includes all cases that were open at some point during the year, but the MTBE monitoring data summary sheets represent only a static point in time, the total number of sites monitoring for MTBE and those monitoring and detecting MTBE, as represented on our graph, are likely to be slightly understated. An aquifer is a water-bearing, underground zone of generally gravel and sand.
Information sources used for the analysis include: LUSTIS databases of the San Francisco and Central Coast RWQCBs; MTBE Summary Sheets, Santa Clara Valley Water District (SCVWD); Facts About MTBE & Drinking Water from SCVWD's web site: http://www.scvwd.dst.ca.us/wtrqual/factmtbe.htm; "A Challenge for the '90s: Protecting Santa Clara County's Water", Santa Clara Valley Water District, 1993; "Trace Levels of MTBE in Drinking Water", San Jose Mercury News, 1/27/98; "Gas Stations Low on Time to Upgrade Tanks", San Jose Mercury News, 7/10/98; "Governor Issues Order to Phase Out MTBE", San Jose Mercury News, 3/26/99.
Endangered Species Listings Accelerate
Much better information is needed to create meaningful indicators of South Bay species and habitats. It is important to note that the dates on the graph do not represent the biological, scientific dates that each species became rare. Rather, the graph reflects the dates that the species were listed as endangered or threatened through the federal or state regulatory process. Another limitation of the graph is that it does not display how well we are managing the endangered and threatened species in Santa Clara County. In other words, local populations of these species may increase or decrease, but this would not be reflected in the graph. Where possible, in this report we have tried to supplement the graph with indicators on local population estimates or habitats.
The animals counted in our data set are ones that occur within, or may be affected by projects within, Santa Clara County. Fish and other aquatic species are included if they are in the same watershed as Santa Clara County or if water use in Santa Clara County might affect them. The plants that are included are ones that have actually been observed in Santa Clara County. Please note that scientists differ in opinion as to which species actually occur in a given county. The species reflected in our data set include those actually observed in Santa Clara County, and in the case of animals and fish, those that may be affected by projects within the County. Information sources used for the analysis include: U.S. Fish & Wildlife Service; California Department of Fish & Game's Natural Diversity Database; California Native Plant Society's Inventory of Rare and Endangered Vascular Plants of California; Species in Danger in Our Own Backyard: Endangered, Threatened and Rare Species in the South San Francisco Bay Area, Peninsula Conservation Center, 1992; Environmental Defense Fund.
Tidal Marshes Decrease by 84%
An estuary is a partially enclosed body of water where river water meets and mixes with ocean water. The term "baylands" is used to describe the lands near the Bay. Information sources used for the analysis include: Baylands Ecosystem Habitat Goals: A report of habitat recommendations prepared by the San Francisco Bay Area Wetlands Ecosystem Goals Project. U.S. Environmental Protection Agency, San Francisco, Calif./S.F. Bay Regional Water Quality Control Board, Oakland, Calif. March 1, 1999; Wetlands information sheet published by the San Francisco Estuary Project, December 1993.
Non-Native Species Crowding Out Native Plants and Animals
The graph reflects modified data, not raw data. The modified data set, which excludes about one-third of the raw data, excludes each record for which the researchers could not determine the year of planting, observation, or collection, or that they judged to result from special expertise, an extraordinary collection effort, or the chance discovery of a highly localized species. Nonetheless, the shapes of the cumulative invasion curves are similar for the raw and modified data, indicating similar trends.
Information sources used for the analysis include: Nonindigenous Aquatic Species in a United States Estuary: A Case Study of the Biological Invasions of the San Francisco Bay and Delta, a Biological Study by Andrew N. Cohen and James T. Carlton for the U.S. Fish & Wildlife Service and The National Sea Grant College Program, Connecticut Sea Grant, 12/95; "Accelerating Invasion Rate in a Highly Invaded Estuary", Andrew N. Cohen and James T. Carlton, Science, 1/23/98; "U.S. Takes Aim at Invading Critters", San Jose Mercury News, 2/4/99; "Annual Performance Report, 1995-96", Santa Clara Valley Water District.
Clapper Rail Rebounds Thanks to Controls on Non-Native Species
Data reflects population estimates, not actual counts. Data points for 91/92, 95/96, 96/97, 97/98, and 98/99 represent the average of a range. Information sources used for the analysis include: San Francisco Bay National Wildlife Refuge Complex; "Feral Cats: Friend or Foe?", J. Mark Frederick, Animal Damage Specialist, U.S. Department of Agriculture, November 1996; Baylands Ecosystem Habitat Goals: A report of habitat recommendations prepared by the San Francisco Bay Area Wetlands Ecosystem Goals Project. U.S. Environmental Protection Agency, San Francisco, Calif./S.F. Bay Regional Water Quality Control Board, Oakland, Calif. March 1, 1999; "Proposition 4 Worries Wildlife Experts", San Jose Mercury News, 11/10/98.
Burrowing Owl Habitat Disappearing in Silicon Valley
The indicator was developed by Lynne Trulio, Ph.D., Associate Professor of Environmental Studies at San Jose State University, using data collected by the consulting firm of H.T. Harvey and Associates. In 1994 H.T. Harvey and Associates prepared a list of 215 sites identified by local birders and consultants as occupied by burrowing owls between 1981 and 1988. They found that on 97% of these sites, there were 10 or fewer birds and on 81% just one or two birds survived.
In the summers of 1995 and 1998 Lynne Trulio surveyed 123 of these sites (which had descriptions accurate enough to find) to determine their fate over the decade. Sites completely converted to a use unacceptable as owl habitat were scored as lost; reduced sites were those diminished in size or habitat quality; existing sites were those which, in Lynne Truilio's opinion, could still support a pair of owls. The sites are located in Palo Alto, Mountain View, Sunnyvale, Santa Clara, San Jose, and Alviso. Moffett Federal Airfield and the San Jose Airport were not included in the survey.
It is important to note that the H.T. Harvey data do have limitations. They are anecdotal and not the result of a rigorous survey. However, they have been considered reliable enough for an analysis of owl population change over time (DeSante, et al., 1995). In addition, the sites were not randomly chosen. Those sites provided by consultants are likely to be biased, since these were probably sites being investigated due to their development potential. Sites from birders do not have this bias, but are likely to be in the more accessible areas. Though imperfect, these data are the best records that exist of owl locations in the 1980s and are a valuable baseline from which to evaluate site change over time.
Further, these data are a subset of the existing owl population and are not an accurate reflection of the number of owls in the Valley. These data also do not indicate how many owls were lost. Although 81% of sites supported only 1 or 2 owls, any particular location may have had between 1 and 10 birds. These data show only the decrease in the number of owl locations which were occupied in 1988.
Information sources used for the analysis include: "The Burrowing Owl as an Environmental Monitor of CEQA Effectiveness & Quality of Life in Silicon Valley" and "Burrowing Owl Habitat Loss: One Indicator of Quality of Life in Silicon Valley", Lynne Trulio, Ph.D., Associate Professor of Environmental Studies, San Jose State University, 8/98; List of Endangered & Threatened Species That May Occur in or Be Affected by Projects in Santa Clara County, U.S. Fish & Wildlife Service, 2/25/99.
Toxic Chemical Releases Edge Upward After Years of Decline
Releases to land and surface water account for very few of the total Toxic Release Inventory (TRI) releases. The TRI list includes 652 chemicals, some of which were added in 1995. Further, starting in 1994 federal facilities were required to report under TRI. Note that the pounds of chemicals released does not necessarily correlate with the public health or environmental impact because hazard varies between chemicals.
Information sources used for the analysis include California Department of Toxic Substances Control. For more information about the Toxic Release Inventory refer to the following websites: http://www.scorecard.org by the Environmental Defense Fund and http://tree2.epa.gov/CEIS/CEIS.NSF/$$All/0606085TRI by the U.S. Environmental Protection Agency's Center for Environmental Information and Statistics.
Use of Most Toxic Pesticides Drops 51% in 6 Years (Excluding Residential Use)
Data on pounds, types, uses, and toxicology of pesticides applied in Santa Clara County is from the California Department of Pesticide Regulation. The term "most toxic" pesticides refers to currently registered pesticide active ingredients in the following 5 categories: 1) Currently registered active ingredients listed on the State's Proposition 65 list of chemicals "known to cause reproductive toxicity"; 2) Currently registered active ingredients listed by U.S. EPA as B2 carcinogens or on the State's Proposition 65 list of chemicals "known to cause cancers"; 3) Pesticides that are cholinesterase inhibitors, that is, organophosphate and carbamate chemicals; 4) Pesticides on the groundwater protection list (California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1, Section 6800A)] and norflurazon, which the California Department of Pesticide Regulation is recommending be listed as a restricted material; and 5) Pesticides from the toxic air contaminants list (California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1, Section 6860). Note that Mineral Oil, Petroleum Distillates, Refined Petroleum Distillates, and Unclassified Petroleum Oil were excluded from our list of "most toxic" pesticides since only a small fraction of the components of these oils are carcinogenic.
Structural pest control represents any pest control work performed within or around buildings or other structures. "Other" pesticide use includes: public health pest control; vertebrate pest control; fumigation of nonfood and nonfeed materials such as lumber, furniture, etc.; pesticides used in research; regulatory pest control used in ongoing control and/or eradication of pest infestations; other fumigation; and uncultivated non-agricultural areas. Information sources used for the analysis include California Department of Pesticide Regulation and Pesticide Action Network.
Hazardous Waste Generation Increases
Information on hazardous wastes comes from the U.S. Environmental Protection Agency's Biennial Reporting System (BRS). BRS is an automated data processing system that contains data from Hazardous Waste Report Forms submitted by regulated hazardous waste generators and handlers.
A site is a Large Quantity Generator if it meets certain threshold criteria established in the regulations. Total waste depicted on the graph is the combined total of Resource Conservation and Recovery Act (RCRA) waste and state-regulated hazardous waste. (A RCRA waste is a solid waste assigned a federal hazardous waste code and regulated by the RCRA law, either because it was managed in a unit subject to RCRA permitting standards or because it was shipped and subject to RCRA hazardous transportation requirements.)
The tonnage of waste reported is meant to give a gross estimate of industrial waste activity in Santa Clara County and the amount of waste generated and managed, rather than an estimate of the risk to local populations. Facilities vary according to how close they are to human population areas and sensitive ecological features. Therefore, the figures shown may not accurately reflect risk to people and the environment.
Information sources used for the analysis include: Environmental Profile for Santa Clara County, California, from the Center for Environmental Information and Statistics website, http://tree2.epa.gov/CEIS/CEIS.NSF/$$All/0606085BRS, which depicts data from the U.S. Environmental Protection Agency's Biennial Reporting System.
Website developed by Clary Meuser Research Associates