5. Affected Environment
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1 5. Affected Environment 2 5.1 Introduction 3 This chapter is a description of the biological, physical, and socioeconomic 4 characteristics, including human uses that could be affected by implementing the action 5 alternatives for this RMP/EIS (see Chapter 3). Where possible, the information and 6 direction for Reclamation resources has been further broken down into fine-scale 7 assessments and information. Specific aspects of each resource discussed in this section 8 were raised during the public and agency scoping process. The level of information 9 presented in this chapter is commensurate with and sufficient to assess potential effects 10 of the action alternatives in Chapter 6. 11 5.2 Resources 12 This section contains a description of the biological and physical resources of the New 13 Melones Lake Area and generally follows the order of topics addressed in Chapter 3, as 14 follows: 15 • Air quality; 30 • Fire management; 16 • Noise; 31 • Cultural resources; 17 • Climate; 32 • Indian Trust Assets; 18 • Geology; 33 • Socioeconomic and 19 • Topography; 34 environmental justice; 20 • Hydrology/water quality; 35 • General recreation; 21 • Visual Resources; 36 • Facilities, land use, and 22 • Vegetation; 37 management areas; 23 • Fish and wildlife; 38 • Aquatic recreation; 24 • Special status species; 39 • Land-based recreation; 25 • General land management; 40 • Interpretive services and 26 • Access and transportation; 41 visitor information; and 27 • Public health and safety; 42 • Utilities. 28 • Invasive species control; 29 October 2009 New Melones Lake Area Draft RMP/EIS Reclamation 5-1 1 5.2.1 Air Quality 2 The New Melones Lake Area’s location in Calaveras and Tuolumne Counties places it in 3 the Mountain Counties Air Basin in the central Sierra Nevada foothills. Air quality 4 problems in this air basin include periodic high levels of ozone and suspended particulate 5 matter. Other air pollutants generally do not occur in concentrations high enough to 6 constitute a problem. 7 Air quality management programs in California are the responsibility of local air 8 pollution control districts (APCDs), the California Air Resources Board (CARB), and the 9 US EPA. The local air pollution control districts for the New Melones Lake Area are the 10 Calaveras County APCD and the Tuolumne County APCD. 11 Federal and state air quality management programs have evolved using a combination of 12 two different approaches: 13 • The state implementation plan (SIP) process of setting ambient air quality 14 standards for acceptable exposure to air pollutants, conducting monitoring 15 programs to identify locations experiencing air quality problems, and then 16 developing programs and regulations designed to reduce or eliminate those 17 problems; and 18 • The hazardous air pollutant process of identifying specific chemical substances 19 that are potentially hazardous to human health and then setting emission standards 20 to regulate the amount of those substances that can be released by individual 21 commercial or industrial facilities or by specific types of equipment. 22 Both the EPA and CARB have adopted ambient air quality standards for various 23 pollutants. Federal ambient air quality standards have been adopted for ozone, suspended 24 particulate matter, carbon monoxide, nitrogen dioxide, sulfur dioxide, and lead. State 25 ambient air quality standards have been adopted for these same pollutants, plus sulfates, 26 hydrogen sulfide, vinyl chloride, and visibility-reducing particles. Federal and state 27 ambient air quality standards for suspended particulate matter have been established for 28 two different size ranges of suspended particles: inhalable particles (designated as 29 particulate matter less than 10 microns in equivalent aerodynamic diameter [PM10]), and 30 fine particles (designated as particulate matter less than 2.5 microns in equivalent 31 aerodynamic diameter [PM2.5]). 32 Ambient air quality in Tuolumne County is monitored in Sonora, specifically ozone, 33 PM10, PM2.5, and carbon monoxide; ambient air quality in Calaveras County is monitored 34 in San Andreas, specifically ozone and carbon monoxide. There is no PM10 or PM2.5 35 monitoring in Calaveras County. 36 High ozone levels in Calaveras and Tuolumne Counties are due almost entirely to 37 pollutant transport from the Central Valley and the San Francisco Bay Area (CARB 38 2001a). Air quality management programs for Calaveras and Tuolumne Counties rely October 2009 New Melones Lake Area Draft RMP/EIS Reclamation 5-2 1 primarily on emission control programs in upwind source areas to provide for eventual 2 attainment of state and federal ozone air quality standards. 3 Ozone monitoring data from Sonora and San Andreas show that the state and federal 4 ozone standards typically are exceeded several times each year, with considerable year- 5 to-year variation (CARB 2007a). Ozone monitoring data from Sonora and San Andreas 6 show no clear trend in either the frequency of violations or the maximum measured 7 ozone levels. PM10 monitoring data from San Andreas in Calaveras County do not show 8 any clear trends in annual average PM10 levels (CARB 2007a). 9 Most hazardous air pollutant regulations relate to specific industrial sources and 10 operations, but California has identified naturally occurring asbestos as a toxic air 11 contaminant. Naturally occurring asbestos is found in serpentine rock and in some types 12 of ultramafic rocks (those most often found in fault zones). CARB has adopted 13 regulations for limiting the amount of naturally occurring asbestos in aggregate material 14 used for surfaces, including those for roads, road shoulders, parking areas, trails, and 15 playgrounds (CARB 2000). CARB also has adopted separate regulations for 16 construction, grading, quarrying, and surface mining that disturb areas of serpentine, 17 ultramafic rocks, or other areas found to have naturally occurring asbestos (CARB 18 2001b). The local APCDs enforce these regulations. 19 Air pollutant emission sources associated with New Melones Lake Area include car and 20 truck traffic, boat and personal watercraft engine emissions, and generators, camp stoves, 21 and campfires at campground facilities. Localized air quality can be lowered at boat 22 ramps where cars, boats, and personal watercraft may idle while launching. Seaplanes 23 and wildfires and prescribed burns on lands surrounding the New Melones Lake Area are 24 additional but infrequent sources of air pollutant emissions. Facility construction is 25 another, temporary and localized, source of fugitive dust and vehicle emissions. 26 5.2.2 Noise 27 In general, background noise levels vary with wind conditions and relative location (on 28 the lake, along the shoreline, or inland). Typical background noise levels are expected to 29 vary from 35 A-weighted decibels (dBA) to 50 dBA, depending on wind conditions. 30 Aircraft overflights represent an intermittent contributor to overall background noise 31 levels. Noise levels are often somewhat higher near such sources as highway traffic, 32 occupied campgrounds, and areas of the lake with boat and personal watercraft use. 33 Intermittent but intense noise sources may occur as a result of floatplane landings and 34 takeoffs, model aircraft flying, amplified music on wakeboard boats and houseboats, and 35 construction or maintenance at various facilities (Reclamation 2006a) or detonations of 36 explosives at the nearby Carson Hill Mine and at the Blue Mountain Minerals Mine in 37 River Canyon. Hunting represents a seasonal, localized, and intermittent source of noise 38 in areas away from campgrounds and other heavily used visitor facilities. Unauthorized 39 off-road vehicle use represents another intermittent noise source affecting some portions 40 of the New Melones Lake Area. October 2009 New Melones Lake Area Draft RMP/EIS Reclamation 5-3 1 The highest overall noise levels are expected to be in the vicinity of campgrounds, the 2 marina, boat launching facilities, and occupied day use areas. In general, noise conditions 3 in the New Melones Lake Area would not interfere with recreational activities and 4 experiences. However, in a 1993 survey during the Independence Day holiday, some 5 visitors complained about excessive nighttime noise in campgrounds and high noise 6 levels from boats. Boats and personal watercraft with underwater engine exhaust and at 7 full throttle generally produce noise levels of 75 to 85 dBA at a distance of 50 feet (15 8 meters) (Lanpheer 2000). 9 5.2.3 Climate 10 The foothills in which New Melones Lake is located are part of the Sierra bioregion, 11 which includes the entire Sierra Nevada, extending approximately 380 miles (610 12 kilometers) along California’s eastern side. Climate at the lake is Mediterranean, 13 meaning that it has wet winters and dry summers. The location of the lake between the 14 higher elevations of the Sierra and the low-lying floor of the Central Valley means that 15 temperatures are moderate and between those found at these two extremes. Because of 16 this transitional location, climatic features, such as temperature and precipitation, 17 fluctuate widely throughout the year. This fluctuation in turn leads to profound yet 18 predictable seasonal variations in the conditions of various resources, including water 19 temperatures and levels, vegetative vigor, and wildlife residency. 20 Localized fluctuations in temperature and precipitation within the project area result from 21 aspect and elevation. These fluctuations are apparent as differences in vegetation 22 patterns, soil formation and stability, and moisture retention. Although these localized 23 variations in resource conditions may affect planning on a project level, climatic resource 24 conditions for the RMP/EIS are reported on a regional level. 25 Climate data shown in Table 5-1 reflect average high and low temperatures and average 26 precipitation from 1992 to 2006. During this time, the maximum recorded temperature at 27 New Melones Dam was 110 degrees Fahrenheit (43 degrees Celsius), while the lowest 28 temperature was 24 degrees F (- 5 degrees Celsius). Extended periods of temperatures at 29 or below freezing are uncommon.