CHAPTER 3 

Air Quality Setting 

3.1 Weather and Climate ......................................................................................... 3-1 

3.2 Air Quality and Area Designations ..................................................................... 3-1 

3.3 PM10 Air Quality ................................................................................................. 3-3 

 3.3.1 Health Impacts of PM10 .................................................................... 3-3 

 3.3.2 Owens Lake Health Advisory Program ............................................. 3-3 

 3.3.3 Monitoring Sites and Data Collection ................................................ 3-4 

 3.3.3.1 PM10 Monitoring Network ................................................. 3-4 

 3.3.3.2 Dust Transport Study ....................................................... 3-5 

 3.3.3.3 PM2.5 Monitoring at Keeler ................................................. 3-5 

 3.3.4 PM10 Data Summary ........................................................................ 3-6 

 3.3.4.1 Number of 24-hour Exceedances ..................................... 3-6 

 3.3.4.2 Annual Average PM10 Concentrations .............................. 3-6 

 3.3.4.3 Peak PM10 Concentrations ................................................ 3-6 

 3.3.4.4 PM10 Trends ...................................................................... 3-7 

3.4 Cancer Risk Due to Owens Lake Dust Storms .................................................. 3-7 

3.5 Visibility and Sensitive Airsheds ....................................................................... 3-8 

3.6 Off-Lake PM10 Violations ................................................................................... 3-9 

3.7 References ....................................................................................................... 3-9 
FIGURES 

Following Page

Figure 3.1 Boundaries of the federal PM10 non-attainment area .............................. 3-2 

Figure 3.2 Locations of PM10 monitor sites near Owens Lake ................................. 3-4 

Figure 3.3 Annual trend for the number of exceedances ......................................... 3-6 

Figure 3.4 Annual average concentrations measured at each site using TEOM 

 monitors. ................................................................................................. 3-6 

Figure 3.5 Yearly comparison of highest Owens Lake PM10 concentrations with 

Highest nationwide values, 1995 to 2006 ............................................... 3-6 

Figure 3.6 Daily 24-hour maximum TEOM PM10 values at Owens Lake, 

2001 to 2006. .......................................................................................... 3-6 

Figure 3.7 Locations of sensitive airsheds near the OVPA ...................................... 3-8 

TABLES 

Page or Following Page

Table 3.1 California and national ambient air quality standards .............................. 3-2 

Table 3.2 Summary of the particulate matter monitoring history for each site ........ 3-6 

Table 3.3 Annual Ranking of Owens Lake PM10 in U.S. ......................................... 3-6 

Table 3.4 Cancer risk at Keeler due to Owens Lake dust storms. .......................... 3-7 

Table 3.5 Sensitive airsheds and their PSD classifications. ................................... 3-8 
3-1 

CHAPTER 3 

Air Quality Setting 

3.1 WEATHER AND CLIMATE 

The Owens Valley Planning Area (OVPA) is located in the southern end of the Owens Valley in 

Inyo County, California. Owens Lake is bounded by the Inyo Mountains to the east, and the 

Sierra Nevada to the west, which rise over 10,000 feet above the lake bed surface. Because it is 

in the rain shadow of the Sierra Nevada, annual rainfall is very low in the project area. Owens 

Lake averages approximately 4 inches of rainfall per year with the majority of that falling from 

November through April. Temperatures range from around 18oF to 70oF during winter, and 45oF 

to 112oF during summer. Hourly average wind speeds in the area can exceed 40 mph as 

measured at a 33-foot height. These winds are generally associated with the passage of lowpressure systems during winter and spring months. The leading edges of these low-pressure 

systems are usually cold fronts that initially produce winds from the south as the colder air mass 

approaches, under-running and displacing the warmer air in its path. As the leading edge of the 

front passes, the wind direction shifts, often resulting in converging winds from the south along 

the east side of the valley and from the north along the west side. Cold winds from the north 

typically follow the passage of the low-pressure system as high pressure begins to build back 

over the area. 

3.2 AIR QUALITY AND AREA DESIGNATIONS 

Air quality is regulated through federal, state and local requirements and standards in the project 

area. Under the Federal Clean Air Act, the U.S. Environmental Protection Agency (USEPA) has 

set ambient air quality standards to protect public health and welfare. National ambient air 

quality standards (NAAQS) have been set for the following criteria pollutants; particulate matter 

less than 10 microns (PM10), particulate matter less than 2.5 microns (PM2.5), ozone, carbon 

monoxide, oxides of nitrogen, sulfur dioxide, and lead. In addition, California has set air quality 

standards for these pollutants, which are usually more stringent, and has added to this list 

standards for vinyl chloride, hydrogen sulfide, sulfates and visibility-reducing particles. Table 

3.1 shows the current California and national ambient air quality standards. 

The OVPA has been designated by the state and the USEPA as non-attainment for the state and 

federal 24-hour average PM10 standards. The boundaries of the federal PM10 nonattainment area 

are shown in Figure 3.1. The area is designated as “attainment” or “unclassified” for all other 

federal ambient air quality standards. Monitoring and research conducted for more than 20 years, 

as well as three previous State Implementation Plans (SIPs), has determined that wind-blown 

dust from the dry bed of Owens Lake is the dominant cause of NAAQS violations for PM10 in 

the non-attainment area. 

The USEPA designated the Owens Valley as a “serious” non-attainment area due to the frequent 

violations of the NAAQS for PM10 and the inability of the area to attain the standard by 

December 31, 1995. For serious PM10 non-attainment areas, the federal Clean Air Act 

Amendments of 1990 (CAAA) required the submittal of a SIP by February 8, 1997 that would 
Air Quality Setting 

3-2 

bring the area into attainment with the NAAQS by December 31, 2001, if practicable. In 

November 1998, the District adopted the 1998 SIP, which was approved by the USEPA on 

August 19, 1999 (Federal Register, 1999). That 1998 SIP required the City of Los Angeles 

(City), the entity responsible for diverting the Lake’s water and exposing the emissive lake bed, 

to use Best Available Control Measures (BACM), which consisted of Shallow Flooding, 

Managed Vegetation, and Gravel Blanket, to reduce PM10 emissions on 16.5 square miles of the 

Owens Lake bed by 2003. The 1998 SIP also provided a five-year extension of the deadline for 

attainment, and committed to a SIP Revision in 2003 that would determine the final control 

strategy to attain the NAAQS by December 31, 2006 (GBUAPCD, 1998a). 

On November 13, 2003, the District approved the 2003 Revised State Implementation Plan for 

the Owens Valley Planning Area (2003 SIP), which was approved by the CARB in February 

2004. The 2003 SIP is currently implemented under Board Order #031113-01. The 2003 SIP 

control strategy required the City to continue to use BACM to control emissions on a total of 

29.8 square miles of the lake bed. The 2003 SIP also required the District to continue to monitor 

PM10 emissions and to require the City to implement additional controls beyond the 29.8 square 

miles, if necessary. (GBUAPCD, 2003) 

In December 2005, a dispute arose between the District and the City regarding requirements to 

control dust from additional areas at Owens Lake beyond the 29.8 square miles identified in the 

2003 SIP (Schade, 2005 and Schade, 2006). On December 4, 2006 a Settlement Agreement was 

approved by both parties to resolve this dispute (GBUAPCD, 2006b). Under the provisions of 

this agreement, the City agreed to implement dust control measures on an additional 13.2 square 

miles of the lake bed by April 1, 2010 and the District agreed to revise the 2003 SIP before 

March 1, 2008 to incorporate the provisions of the Settlement Agreement. 

On March 23, 2007, the USEPA published a finding that the Owens Valley Planning Area did 

not attain the 24-hour NAAQS for PM10 by December 31, 2006 as mandated by the CAAA 

(USEPA, 2007a). As a result of this finding, the Owens Valley SIP must be revised to include a 

control strategy that will provide for attainment in the Owens Valley Planning Area as soon as 

practicable, by achieving at least a 5 percent reduction in PM10 emissions per year. The 2008 SIP 

must demonstrate that the NAAQS can be attained by March 23, 2012, unless the USEPA grants 

an extension which could extend the deadline up to March 23, 2017 (CAAA §179(d)(3)). The 

USEPA may consider the severity of nonattainment and the feasibility of applying available 

control measures in deciding if an extension should be granted. In accordance with CAAA 

§189(d), the revised SIP must be submitted to the USEPA by December 31, 2007. 

At the time the 2003 SIP was approved by the District and the CARB in November 2003, the 

USEPA policy direction on PM10 attainment demonstrations was that the control measures that 

were needed to demonstrate attainment must be implemented by December 31, 2006. After the 

2003 SIP was adopted, the USEPA policy direction changed to require three continuous years of 

air quality data without violations prior to December 31, 2006 to demonstrate attainment. This 

change in policy direction effectively made the 2003 SIP attainment demonstration deficient, 

since all the control measures should have been implemented before the end of 2003 to meet the 

attainment deadline. Because it takes two to three years to implement the Shallow Flooding and 

Managed Vegetation control measures, the construction of the 2003 SIP dust control measures 

were not completed until the end of 2006. Numerous NAAQS violations occurred during the 
Concentration 3 Method 4 Primary 3,5 Secondary 3,6 Method 7

1 Hour 0.09 ppm (180 μg/m3

) —

8 Hour 0.070 ppm (137 μg/m3

) 0.08 ppm (157 μg/m3)

24 Hour 50 μg/m3 150 μg/m3

Annual 

Arithmetic Mean 20 μg/m3 —

24 Hour 35 μg/m3

Annual 

Arithmetic Mean 12 μg/m3 Gravimetric or Beta Attenuation 15 μg/m3

8 Hour 9.0 ppm (10mg/m3

) 9 ppm (10 mg/m3)

1 Hour 20 ppm (23 mg/m3

) 35 ppm (40 mg/m3)

8 Hour 

(Lake Tahoe) 6 ppm (7 mg/m3

) — ——

Annual 

Arithmetic Mean 0.030 ppm (56 μg/m3) 0.053 ppm (100 μg/m3

)

1 Hour 0.18 ppm (338 μg/m3

) —

Annual 

Arithmetic Mean — 0.030 ppm (80 μg/m3

) —

24 Hour 0.04 ppm (105 μg/m3

) 0.14 ppm (365 μg/m3) —

3 Hour — — 0.5 ppm (1300 μg/m3

)

1 Hour 0.25 ppm (655 μg/m3

) — ——

30 Day Average 1.5 μg/m3 — ——

Calendar Quarter — 1.5 μg/m3 Same as 

Primary Standard

High Volume 

Sampler and Atomic 

Absorption

No 

Sulfates 24 Hour 25 μg/m3 Ion Chromatography

Federal

Hydrogen 

Sulfide 1 Hour 0.03 ppm (42 μg/m3

) Ultraviolet 

Fluorescence Standards

Vinyl 

Chloride8 24 Hour 0.01 ppm (26 μg/m3

) Gas 

Chromatography

For more information please call ARB-PIO at (916) 322-2990 California Air Resources Board (02/22/07)

Inertial Separation 

and Gravimetric 

Analysis

Ambient Air Quality Standards

Pollutant Averaging 

Time

Ozone (O3) Ultraviolet 

Photometry

Ultraviolet 

Photometry

California Standards 1 Federal Standards 2

Respirable 

Particulate 

Matter 

(PM10)

Atomic Absorption

* The Nitrogen Dioxide ambient air quality standard was amended on February 22, 2007, to lower the 1-hr standard to 0.18 ppm 

and establish a new annual standard of 0.030 ppm. These changes become effective after regulatory changes are submitted and 

approved by the Office of Administrative Law, expected later this year.

Gas Phase 

Chemiluminescence

Nitrogen 

Dioxide 

(NO2) *

Same as 

Primary Standard

Gas Phase 

Chemiluminescence

Lead8

Spectrophotometry 

(Pararosaniline 

Method)

Extinction coefficient of 0.23 per kilometer — 

visibility of ten miles or more (0.07 — 30 

miles or more for Lake Tahoe) due to 

particles when relative humidity is less than 

70 percent. Method: Beta Attenuation and 

Transmittance through Filter Tape.

8 Hour 

Visibility 

Reducing 

Particles

See footnotes on next page ...

Same as 

Primary Standard

Sulfur 

Dioxide 

(SO2)

Ultraviolet 

Fluorescence

Same as 

Primary Standard

No Separate State Standard

Same as 

Primary Standard

Carbon 

Monoxide 

(CO)

Fine 

Particulate 

Matter 

(PM2.5)

Gravimetric or 

Beta Attenuation

Inertial Separation 

and Gravimetric 

Analysis

Non-Dispersive 

Infrared Photometry 

(NDIR)

None

Non-Dispersive 

Infrared Photometry 

(NDIR)

Table 3.1 - California and National Ambient Air Quality Standards
1. California standards for ozone, carbon monoxide (except Lake Tahoe), sulfur dioxide (1 and 24 hour),

nitrogen dioxide, suspended particulate matter—PM10, PM2.5, and visibility reducing particles, are 

values that are not to be exceeded. All others are not to be equaled or exceeded. California ambient air 

quality standards are listed in the Table of Standards in Section 70200 of Title 17 of the 

California Code of Regulations.

2. National standards (other than ozone, particulate matter, and those based on annual averages or 

annual arithmetic mean) are not to be exceeded more than once a year. The ozone standard is

attained when the fourth highest eight hour concentration in a year, averaged over three years, 

is equal to or less than the standard. For PM10, the 24 hour standard is attained when the expected 

number of days per calender year with a 24-hour average concentration above 150 μg/m3

 is equal

to or less than one. For PM2.5, the 24 hour standard is attained when 98 percent of the daily

concentrations, averaged over three years, are equal to or less than the standard.

Contact U.S. EPA for further clarification and current federal policies.

3. Concentration expressed first in units in which it was promulgated. Equivalent units given in 

parentheses are based upon a reference temperature of 25°C and a reference pressure of 760 torr. 

Most measurements of air quality are to be corrected to a reference temperature of 25°C and a 

reference pressure of 760 torr; ppm in this table refers to ppm by volume, or micromoles of

pollutant per mole of gas.

4. Any equivalent procedure which can be shown to the satisfaction of the ARB to give equivalent 

results at or near the level of the air quality standard may be used.

5. National Primary Standards: The levels of air quality necessary, with an adequate margin of safety to

protect the public health.

6. National Secondary Standards: The levels of air quality necessary to protect the public welfare 

from any known or anticipated adverse effects of a pollutant.

7. Reference method as described by the EPA. An “equivalent method” of measurement may be used 

but must have a “consistent relationship to the reference method” and must be approved by the EPA.

8. The ARB has identified lead and vinyl chloride as 'toxic air contaminants' with no threshold level of 

exposure for adverse health effects determined. These actions allow for the implementation of 

control measures at levels below the ambient concentrations specified for these pollutants.

For more information please call ARB-PIO at (916) 322-2990 California Air Resources Board (02/22/07)


	

     	





		
	
BLANK PAGE 
Air Quality Setting 

3-3 

3-year attainment demonstration period. As a result, the USEPA made the finding that the 

Owens Valley failed to attain the standard as required under CAAA §189(d). 

The USEPA did not take action on the approval or disapproval of the 2003 SIP, but it has been 

approved by both the District and the state and is currently enforced by the District. By 

December 31, 2006, the City had implemented dust control measures on all 29.8 square miles of 

the lake bed as required in the 2003 SIP. 

This 2008 SIP revises the 2003 SIP and includes an updated analysis of the particulate matter air 

pollution problem in the Owens Valley and a revised control strategy to bring the area into 

attainment with the federal air quality standard for particulate matter as soon as practicable. This 

2008 SIP also incorporates provisions of the Settlement Agreement between the District and the 

City to expand dust control measures to additional areas at Owens Lake in order to attain the 

NAAQS as soon as practicable (GBUAPCD, 2006b). 

3.3 PM10 AIR QUALITY 

3.3.1 Health Impacts of PM10

Particulate pollution is generally associated with dust, smoke and haze and can be measured as 

PM10, which indicates particulate matter less than 10 microns in average aerodynamic diameter. 

These particles are extremely small, one-seventh the diameter of a human hair or 400 times 

smaller than the period at the end of this sentence. Because of their small size, the particles can 

easily penetrate into the lungs. Breathing PM10 can cause a variety of health problems. It can 

increase the number and severity of asthma and bronchitis attacks. It can cause breathing 

difficulties in people with heart or lung disease, and it can increase the risk for, or complicate, 

existing respiratory infections. Children, the elderly and people with existing heart and lung 

problems are especially sensitive to elevated levels of PM10. Even healthy people can be 

adversely affected by dust at extremely high concentrations. The USEPA has set an episode level 

of 600 μg/m3 (averaged over 24 hours) as the level that can pose a significant risk of harm to the 

health of the general public (40 CFR 51.151). 

3.3.2 Owens Lake Health Advisory Program 

The NAAQS for PM10 is frequently violated in the Owens Valley Planning Area because of 

wind-blown dust from Owens Lake. Wind speeds greater than about 17 mph have the potential 

to cause significant wind erosion from the barren lake bed. Ambient PM10 readings are the 

highest measured in the country (USEPA, 2007a). Prior to implementing dust control measures 

on the lake bed, twenty-four-hour average PM10 concentrations measured at the Dirty Socks 

monitor site at times exceeded 12,000 μg/m3—more than 80 times higher than the 24-hour 

NAAQS of 150 μg/m3

. 

In 1995, the District instituted a program to advise the public when unhealthful levels of 

particulate pollution occur in the Owens Valley area. Under this program, the District issues Air 

Pollution Health Advisories when dust storms from Owens Lake cause PM10 concentrations that 

exceed selected trigger levels. Health Advisory notices are faxed to schools and doctor’s offices 

in the area and to local news media. 
Air Quality Setting 

3-4 

• Stage 1 Air Pollution Health Advisories are issued when hourly PM10 levels exceed 400 

μg/m3

. The Stage 1 Health Advisory recommends children, the elderly, and people with 

heart or lung problems refrain from strenuous outdoor activities in dust-impacted areas. 

• Stage 2 Air Pollution Health Advisories are issued when hourly PM10 levels exceed 800 

μg/m3

, and recommends that everyone refrain from strenuous outdoor activities in dustimpacted areas. 

From fall of 1995 through spring of 2007, over 150 advisories were issued as part of the Owens 

Lake Air Pollution Health Advisory program. This program is not intended to replace the need to 

control the dust problem at Owens Lake, but is intended to help reduce adverse health effects 

until dust control measures are in place. The health advisory program will remain in effect until 

dust control measures are fully implemented at Owens Lake and PM10 levels no longer violate 

the NAAQS. 

3.3.3 Monitoring Sites and Data Collection 

3.3.3.1 PM10 Monitoring Network 

Ambient PM10 measurements to determine compliance with the federal PM10 standard have been 

taken at Keeler, Olancha and Lone Pine for over 20 years (Figure 3.2). Meteorological data are 

also collected at each of these permanent monitoring sites to provide wind speed, wind direction, 

and temperature information. An upper air profiler was operated from March to May 2000 and 

January to September 2001 at Dirty Socks and from October 2001 to June 2003 at the Mill Site 

to measure upper level wind speeds and temperature profiles. Precipitation data are collected at 

the Keeler site and humidity and barometric pressure are recorded at the Olancha site. Four 

additional PM10 sites were set up on the shoreline of Owens Lake as part of the Owens Lake 

Dust Identification Program. These are Dirty Socks (Summer 1999), Shell Cut and Flat Rock 

(both set up in January 2001) and the Bill Stanley site (March 2002). Other sites that were or still 

are monitored for PM10 from Owens Lake include the Navy 1 site at the Coso Known 

Geothermal Resource Area and the Coso Junction site. These sites are about 10 miles south of 

the Owens Valley planning area. The Coso Junction PM10 monitor is currently providing hourly 

PM10 measurements and the Navy 1 monitor was discontinued in 1998. 

The Lone Pine Paiute-Shoshone Tribe installed a PM10 monitor on the Lone Pine reservation in 

2002 and a PM2.5 monitor in 2006. Both monitors are Tapered Element Oscillating Microbalance 

(TEOM) monitors that provide hourly concentration data. They are operated in accordance with 

federal monitoring guidelines (40 CFR, Part 58). The monitor site is located southeast of the 

District’s Lone Pine monitor site. Data from the Lone Pine Tribe’s PM10 TEOM have closely 

paralleled the values recorded by the District’s Lone Pine TEOM, although specific dust plumes 

may cause high values at one of these TEOMs and yet miss the other. 

Currently, all the PM10 monitor sites in the planning area are equipped with TEOM continuous 

PM10 samplers (EPA Manual Reference Method: EQPM-1090-079) that provide hourly and 

daily PM10 concentrations. TEOMs are USEPA equivalent method particulate monitors. Some of 

the monitoring sites began collecting PM10 data with High-Volume (Hi-Vol) samplers (Wedding 

[RFPS-1087-062] or Graseby [RFPS-1287-063]). Changes in primary sampler type, from HiVols to TEOMs, are indicated in Table 3.2. All Owens Lake monitoring sites, except the Bill 

Stanley site were also equipped with Partisol PM10 samplers (RFPS-1298-126 and RFPS-1298-

127), which are filter-based USEPA-approved reference method samplers that were operated to 


	


	


		






	


	



	






	

 



		


 	

	

	 	





	





      








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Air Quality Setting 

provide 24-hour average PM10 concentrations. The Partisol samplers confirm the 24-hour 

averages of the TEOM samplers (Parker, 2003). Table 3.2 summarizes the particulate matter 

monitoring history at each site in the Planning Area. 

The District performed a detailed study of different types of PM10 monitors and found significant 

differences in the concentrations measured by collocated monitors of different types. The 

District’s analysis showed that TEOM and Partisol samplers provide the most consistent 

measurements at Owens Lake, and that they are the most suitable monitors for measuring PM10

caused by wind-blown dust (Ono, et al., 2000). 

3.3.3.2 Dust Transport Study 

Historically, the permanent PM10 monitoring stations were operated on a one-in-six day schedule 

to sample PM10, and did not sample on the other five off-schedule days. This was changed for a 

period from March 1993 to June 1995 to collect data to assess the PM10 impacts downwind from 

Owens Lake toward the City of Ridgecrest. A special-purpose monitoring network was set up 

adding the southern communities of Pearsonville, Inyokern and Ridgecrest. During the specialpurpose monitoring period, samplers at both Owens Lake and the southern sites were operated 

on days when Owens Lake dust events were forecast to have impacts toward the south. The 

results of this study showed that Owens Lake dust plumes caused exceedances of the PM10

NAAQS as far as Ridgecrest, 60 miles south of the lake. The 1998 SIP (GBUAPCD, 1998a) 

includes the monitoring data from this episode-monitoring program. 

About 40,000 permanent residents from Ridgecrest to Bishop are affected by the dust from 

Owens Lake. In addition, many visitors spend time in this dust-impacted area, to enjoy the many 

recreational opportunities the Eastern Sierra and high desert have to offer. Lone Pine annually 

hosts the Lone Pine film festival, which draws thousands of visitors from outside the area. The 

National Park Service is concerned about the health hazard posed to the 86,000 people that 

annually visit the Manzanar National Historic Site, 15 miles north of Owens Lake. The Park 

Service is concerned because a high percentage of the visitors to Manzanar are older visitors 

who are more prone to airborne respiratory threats, and that they will spend 3 to 4 hours outdoors 

in a potentially harmful environment (Hopkins, 1997). 

3.3.3.3 PM2.5 Monitoring at Keeler 

Monitoring of fine particulate matter (PM2.5) on a 1-in-3-day schedule was initiated in 1999 at 

Keeler. Eight years of PM2.5 data show a rough correspondence between PM2.5 levels and PM10

levels at the Keeler site. A high value of 193 μg/m3

, recorded on December 28, 2006, indicates 

that a serious fine particulate pollution problem may exist at this site. However, the current PM2.5

NAAQS is 35 μg/m3

 for the 98th percentile value at a monitor in a calendar year. This allows 

seven exceedances of the 35 μg/m3

 standard per year without violating the standard. Therefore, 

there was not a violation of the PM2.5 NAAQS at Keeler for 2006 because the 98th percentile 

(eighth highest) value was below 35 μg/m3

, despite this one high value. To date, no violations of 

the PM2.5 NAAQS have been documented in Keeler. 

In the near future, the District is planning to upgrade to daily PM2.5 monitoring at Keeler in an 

effort to better characterize fine particulate levels there. 

3-5 
Air Quality Setting 

3-6 

3.3.4 PM10 Data Summary 

3.3.4.1 Number of 24-hour Exceedances 

From 1993 through 2006, almost daily PM10 sampling recorded 208 PM10 exceedances at Keeler. 

This averages about 15 exceedances of the PM10 NAAQS per year. The Dirty Socks monitor 

recorded 205 PM10 exceedance days over a seven year period from January 2000 to December 

2006. Dirty Socks averaged over 29 exceedances per year and had the highest concentrations of 

the seven sites monitored. Figure 3.3 shows the number of exceedances from 1994 through 2006 

at each site. All six monitor sites were in violation of the 24-hour average PM10 NAAQS, which 

allows no more than one exceedance per year over a three year period. 

3.3.4.2 Annual Average PM10 Concentrations 

Figure 3.4 shows the annual PM10 concentration trend for six Owens Lake sites from 1994 

through 2002. Although the USEPA eliminated an annual PM10 NAAQS in 2006, it is instructive 

to track annual PM10 averages in order to observe trends (Prior to its elimination, the annual 

PM10 NAAQS was 50 μg/m3

). Since the installation of a PM10 monitor at Dirty Socks in 1999, 

this monitor site has consistently registered the highest concentrations measured at Owens Lake. 

The three-year annual average for Dirty Socks was estimated at 157 μg/m3

 for the years 2000-

2002. Only once (2005) in seven years of operation has the annual average PM10 concentration 

in Dirty Socks monitoring site dropped below 50 μg/m3

. The Shell Cut monitoring site has 

produced an annual average above 50 μg/m3 for the years 2002 through 2006, as well. 

3.3.4.3 Peak PM10 Concentrations 

The 24-hour average PM10 measurements from Owens Lake sites are consistently listed as the 

highest concentrations in the United States on the USEPA’s AIRData website (USEPA, 2007c). 

PM10 concentrations exceeding 20,000 μg/m3 have been measured at the Dirty Socks monitor 

site using a partisol PM10 monitor. This is more than 133 times higher than the 24-hour NAAQS 

of 150 μg/m3

. Partisols are Federal Reference Method monitors that collect samples on a filter 

that are weighed in the lab and are operated once every third day. However, note that most of the 

PM10 data shown in Table 3.2 are based on automated TEOM PM10 measurements which 

provide hourly and daily concentrations and are another federally approved PM10 monitor. Table 

3.3 compares Owens Lake values with the rest of the United States. 

In the data available on the USEPA’s AIRData website, Owens Lake has produced the highest 

PM10 reading in the nation in all but one of the past eleven years. As shown graphically in Figure 

3.5, Owens Lake concentrations have consistently dwarfed values reported from the rest of the 

nation since 2000. Table 3.3 also contains PM10 values measured at Mono Lake, which is in the 

District to the north of the Owens Valley PM10 Planning Area. Mono Lake has also consistently 

exceeded all PM10 readings in the rest of the nation since 2000. Mono Lake PM10 exceedances 

are also caused by the City of Los Angeles’ Eastern Sierra water diversions (GBUAPCD, 1995). 

The highest PM10 concentration for any of the PM10 monitor sites at Owens Lake on each date 

for a six-year period is shown in Figure 3.6. PM10 concentrations are shown on a logarithmic 

scale due to the extreme concentration range. The seasonal nature of the dust events can also be 

seen in this figure. Most dust events occur during winter and spring. There are few violations 

recorded during summer and fall months. 
0

5

10

15

20

25

30

35

40

45

1994 1996 1998 2000 2002 2004 2006

YEAR

# of PM-10 Exceedances/Year

Keeler Lone Pine

Olancha Dirty Socks

Flat Rock Shell Cut

Bill Stanley

Figure 3.3 - All seven Owens Lake monitoring sites have violated the NAAQS (150 μg/m3

) by 

averaging more than one exceedance per year of the 24-hour standard. 

0

50

100

150

200

250

1994 1996 1998 2000 2002 2004 2006

YEAR

Annual Avg. PM-10 (μg/m3

)

Keeler Lone Pine

Olancha Dirty Socks

Flat Rock Shell Cut

Figure 3.4 - The 3-year annual average PM10 concentrattions measured at Dirty Socks and 

Shell Cut both violated the PM10 annual NAAQS of 50 μg/m3

. 
0 5000 10000 15000 20000

All Other U.S. PM-10

Owens Lake

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

1996

1995

Figure 3.5 - Yearly comparison of highest Owens Lake PM10 concentrations with highest 

 concentrations at all U.S. PM10 monitoring sites outside the GBUAPCD 
10

100

1000

10000

100000

2001 (43 Exceedances)

10

100

1000

10000

100000

2002 (46 Exceedances)

10

100

1000

10000

100000

2003 (37 Exceedances)

10

100

1000

10000

100000

2004 (34 Exceedances)

10

100

1000

10000

100000

2005 (26 Exceedances)

10

100

1000

10000

100000

2006 (36 Exceedances)

Figure 3.6 - Daily 24-hour maximum PM-10 values at Owens Lake monitoring sites, 2001 - 2006
Table 3.2 Summary of the particulate matter monitoring history for each site

Peak Number Adjusted Number

24-Hour of # of Annual 3-Year Sample Primary

Site Year Value Exceeds Exceeds Average Average Days Monitor

KEELER 1987 672 4 24 46.70 60 Hi Vol

KEELER 1988 394 2 12 31.75 58 Hi Vol

KEELER 1989 1861 4 Invalid 55 Hi Vol

KEELER 1990 858 2 Invalid 20 Hi Vol

KEELER 1991 181 1 Invalid 47 Hi Vol

KEELER 1992 526 3 18 37.34 59 Hi Vol

KEELER 1993 781 1 6 43.16 58 Hi Vol

KEELER 1994 1381 20 Invalid 297 TEOM

KEELER 1995 3929 23 Invalid 311 TEOM

KEELER 1996 862 15 15 Invalid 309 TEOM

KEELER 1997 835 12 12 30.81 341 TEOM

KEELER 1998 1464 17 17 35.08 353 TEOM

KEELER 1999 2569 19 19 50.41 38.76 364 TEOM

KEELER 2000 1101 18 18 42.56 42.68 365 TEOM

KEELER 2001 1400 9 9 40.16 44.38 353 TEOM

KEELER 2002 1077 13 13 14.75 39.86 365 TEOM

KEELER 2003 1209 11 11 29.87 35.63 364 TEOM

KEELER 2004 3322 14 14 39.46 35.40 363 TEOM

KEELER 2005 1441 7 7 26.99 32.11 364 TEOM

KEELER 2006 2101 11 11 33.18 33.21 365 TEOM

LONE PINE 1987 178 1 6 23.27 58 Hi Vol

LONE PINE 1988 172 1 6 21.60 60 Hi Vol

LONE PINE 1989 126 0 0 22.73 22.53 61 Hi Vol

LONE PINE 1990 68 0 0 17.15 20.49 61 Hi Vol

LONE PINE 1991 82 0 0 17.90 19.26 59 Hi Vol

LONE PINE 1992 63 0 0 17.15 17.40 57 Hi Vol

LONE PINE 1993 170 1 5 17.02 17.36 117 Hi Vol

LONE PINE 1994 499 3 3 22.23 18.80 352 TEOM

LONE PINE 1995 392 5 5 23.12 20.79 363 TEOM

LONE PINE 1996 166 1 1 17.71 21.02 336 TEOM

LONE PINE 1997 123 0 0 16.86 19.23 360 TEOM

LONE PINE 1998 472 5 5 23.62 19.40 346 TEOM

LONE PINE 1999 325 3 3 22.18 20.89 350 TEOM

LONE PINE 2000 180 2 2 19.30 21.70 360 TEOM

LONE PINE 2001 260 2 18.94 20.14 332 TEOM

LONE PINE 2002 315 7 7 26.59 21.61 365 TEOM

LONE PINE 2003 724 4 4 21.57 22.37 365 TEOM

LONE PINE 2004 349 1 1 20.27 22.81 355 TEOM

LONE PINE 2005 262 1 1 17.20 19.68 364 TEOM

LONE PINE 2006 293 2 2 20.33 19.26 361 TEOM
Table 3.2 Continued

Peak Number Adjusted Number

24-Hour of # of Annual 3-Year Sample Primary

Site Year Value Exceeds Exceeds Average Average Days Monitor

OLANCHA 1987 31 0 Invalid 31 Hi Vol

OLANCHA 1988 55 0 0 19.00 57 Hi Vol

OLANCHA 1989 109 0 Invalid 52 Hi Vol

OLANCHA 1990 200 2 12 23.19 61 Hi Vol

OLANCHA 1991 181 1 6 18.04 59 Hi Vol

OLANCHA 1992 366 2 6 19.66 20.30 60 Hi Vol

OLANCHA 1993 346 3 Invalid 36 Hi Vol

OLANCHA 1994 362 2 Invalid 94 Hi Vol

OLANCHA 1995 2252 4 Invalid 207 TEOM

OLANCHA 1996 2383 8 8 33.22 354 TEOM

OLANCHA 1997 2229 12 12 36.52 350 TEOM

OLANCHA 1998 327 5 5 19.38 29.71 358 TEOM

OLANCHA 1999 353 5 5 23.07 26.32 356 TEOM

OLANCHA 2000 417 5 5 20.54 21.00 365 TEOM

OLANCHA 2001 1545 3 3 25.37 22.99 352 TEOM

OLANCHA 2002 905 7 7 31.86 25.92 365 TEOM

OLANCHA 2003 1062 5 5 23.23 26.82 359 TEOM

OLANCHA 2004 408 6 6 22.24 25.78 365 TEOM

OLANCHA 2005 288 5 5 19.64 21.71 363 TEOM

OLANCHA 2006 428 2 2 22.94 21.61 364 TEOM

DIRTY SOCKS 1999 2182 10 Invalid 185 TEOM

DIRTY SOCKS 2000 10549 33 33 141.21 365 TEOM

DIRTY SOCKS 2001 12153 41 41 229.11 339 TEOM

DIRTY SOCKS 2002 6702 40 40 130.90 167.07 365 TEOM

DIRTY SOCKS 2003 10933 32 32 135.77 165.26 365 TEOM

DIRTY SOCKS 2004 4472 21 21 85.77 117.48 365 TEOM

DIRTY SOCKS 2005 3087 19 19 43.99 88.51 365 TEOM

DIRTY SOCKS 2006 4169 18 18 63.39 64.38 364 TEOM

FLAT ROCK 2001 1779 8 8 28.00 354 TEOM

FLAT ROCK 2002 759 6 6 25.89 359 TEOM

FLAT ROCK 2003 395 3 3 16.98 23.62 363 TEOM

FLAT ROCK 2004 626 4 4 20.04 20.97 348 TEOM

FLAT ROCK 2005 346 2 2 15.52 17.51 365 TEOM

FLAT ROCK 2006 6171 6 6 36.73 24.10 364 TEOM

SHELL CUT 2001 2660 14 14 35.08 351 TEOM

SHELL CUT 2002 2840 19 19 68.44 361 TEOM

SHELL CUT 2003 9162 17 17 75.87 59.80 342 TEOM

SHELL CUT 2004 2990 20 20 58.89 67.73 366 TEOM

SHELL CUT 2005 3989 13 13 55.08 63.28 359 TEOM

SHELL CUT 2006 6847 12 12 58.20 57.39 365 TEOM
Table 3.2 Continued

Peak Number Adjusted Number

24-Hour of # of Annual 3-Year Sample Primary

Site Year Value Exceeds Exceeds Average Average Days Monitor

COSO JUNCTION 1987 196 1 6 33.53 59 Hi Vol

COSO JUNCTION 1988 92 0 0 33.53 59 Hi Vol

COSO JUNCTION 1989 227 1 6 27.13 27.43 61 Hi Vol

COSO JUNCTION 1990 866 1 6 29.38 26.05 60 Hi Vol

COSO JUNCTION 1991 93 0 0 18.80 25.10 60 Hi Vol

COSO JUNCTION 1992 38 0 Invalid 36 Hi Vol

COSO JUNCTION 1993 254 2 Invalid 51 Hi Vol

COSO JUNCTION 1994 388 1 Invalid 49 Hi Vol

COSO JUNCTION 1995 692 2 12 18.60 55 Hi Vol

COSO JUNCTION 1996 309 1 Invalid 47 Hi Vol

COSO JUNCTION 1997 92 0 Invalid 54 Hi Vol

COSO JUNCTION 1998 409 1 6 22.81 59 Hi Vol

COSO JUNCTION 1999 46 0 0 13.96 114 Hi Vol

COSO JUNCTION 2000 74 0 0 14.56 17.11 110 Hi Vol

COSO JUNCTION 2001 100 0 0 11.42 13.31 122 Hi Vol

COSO JUNCTION 2002 175 1 3 17.63 14.53 112 Hi Vol

COSO JUNCTION 2003 484 1 3 20.10 16.38 110 Hi Vol

COSO JUNCTION 2004 66 0 0 14.40 17.37 121 Hi Vol

COSO JUNCTION 2005 97 0 0 17.89 17.46 119 Hi Vol

COSO JUNCTION 2006 296 1 1 19.09 17.12 273 TEOM

BILL STANLEY 2002 539 1 Invalid 154 TEOM

BILL STANLEY 2003 2196 3 Invalid 92 TEOM

BILL STANLEY 2004 191 2 Invalid 166 TEOM

BILL STANLEY 2005 880 1 Invalid 261 TEOM

BILL STANLEY 2006 322 3 3 17.69 356 TEOM

Notes:

(1) Number of samples 150 μg/m3 or more.

(2) If not daily sampling, number of exceeds is divided by sampling frequency (e.g., divide by 1/6 for 1-in-six-day sampling).

(3) Annual average is invalid if less than 75% of scheduled samples are collected in each of four quarters.

(4) One quarter (3rd) at 73% data capture. District views data as valid.
Table 3.3 – Annual Ranking of Owens Lake PM10 in U.S. 

 

YEAR 

Owens Lake 

Highest in 

U.S.? 

Highest 

Owens Lake 

Value 

Highest Mono 

Lake Value 

Highest 

 non-GBUAPCD 

Value 

1995 Yes 3,929 - 384 

1996 Yes 2,383 - 1,715 

1997 Yes 2,229 - 1,264 

1998 No 1,464 - 1,477 

1999 Yes 2,901 - 442 

2000 Yes 10,842 10,466 508 

2001 Yes 20,754 4,482 610 

2002 Yes 7,915 6,505 590 

2003 Yes 16,619 5,745 590 

2004 Yes 5,225 987 625 

2005 Yes 3,989 2,108 760 

2006 Yes 8,299 4,300 1,079 

 
BLANK PAGE 
Air Quality Setting 

For days when the 24-hour PM10 standard is violated, peak hourly wind speeds at the Owens 

Lake monitoring sites have been measured up to 50 mph. However, violations have also been 

recorded when the hourly wind speed peaked at a more modest 20 mph. The daily average wind 

speed when the 24-hour PM10 standard is violated ranges from 5 to 33 mph, since many 

violations occur with winds that last only a few hours. 

3.3.4.4 PM10 Trends 

Although dust control measures were in place on 29.8 square miles of lake bed by the end of 

2006, PM10 levels at Owens Lake have remained high at the monitoring sites. Monitoring of 

PM10 levels beginning in 2007 will be necessary to establish the overall air quality improvements 

resulting from the first phases of dust control measure implementation. Some improvement in 

exceedances per year (Figure 3.3) and in annual average PM10 concentration (Figure 3.4) at 

Keeler and Dirty Socks may indicate signs of improvement, but are yet to show that the NAAQS 

are being met. At Keeler, the average TEOM value for the years 1993 through 2000 was 

45 μg/m3

. This was prior to the construction of dust control measures on the nearby North Sand 

Sheet. The average TEOM value for the years 2002 through 2006, after dust control measures on 

the North Sand Sheet were operational, was 34 μg/m3

. The inter-year comparisons in Figure 3.6 

indicate an overall reduction in exceedances per year and a reduction in daily peak values at 

Owens Lake monitors. Keeler and Dirty Socks appear to be trending toward significant 

reductions in PM10 levels, but the other sites have yet to show significant improvements. 

3.4 CANCER RISK DUE TO OWENS LAKE DUST STORMS 

In addition to the high levels of fine particulate matter, Owens Lake dust also contains cadmium, 

arsenic and other toxic metals that are at levels above those in soils in the Owens Valley due to 

natural concentration in the terminal lake. These metals pose a significant risk for additional 

cancer cases in the areas of greatest dust impact. Table 3.4 shows that the cancer risk at Keeler, 

associated with cadmium and arsenic in the Owens Lake dust, is estimated at 23 additional cases 

in a million. This is based on an annual concentration average of 45 μg/m3

 from the dust storms, 

breathed over a 70-year period. The value of 45 μg/m3

 is taken from the seven-year average of 

PM10 concentrations measured using a TEOM at Keeler (1993-2000). This average represents 

the annual average prior to the implementation of controls. 

Under the District’s adopted air toxics policy, a toxic risk greater than one in a million additional 

cancer cases is considered to be significant. This policy requires implementation of controls on 

sources that pose a risk greater than one in a million in order to reduce the risk, and it prohibits 

the issuance of a permit to sources that exceed a risk of 10 in a million (GBUAPCD, 1987). A 

revised cancer risk from arsenic and cadmium, using the reduced average dust concentration of 

34 μg/m3 at Keeler, would result in 17 cases per million, a significant reduction in cancer risk. 

Model calculations project an average Keeler PM10 concentration of 21 μg/m3 after all dust 

control measures are operational. This would result in even greater reduction in cancer risk. 

Since this residual dust would contain a smaller fraction of lake bed-derived material than under 

pre-dust-control conditions, the benefits for reduction in cancer risk would be compounded. 

3-7 
Air Quality Setting 

3-8 

Table 3.4 Inhalation cancer risk at Keeler due to Owens Lake dust storms 

 Cancer Toxic Metal 

Toxic Potency Concentration Inhalation 

Metal (μg/m3)

-1 (parts per million) Cancer Risk

Cadmium 4.2 x 10-3 29 5 per million 

Arsenic 3.3 x 10-3 118 18 per million 

Lifetime Cancer Risk = 23 per million 

• Cancer potency from the Air Toxics Hot Spots Program (OEHHA, 2002). 

• Dust samples are taken from Keeler PM10 filters, with concentrations measured by x-ray 

 fluorescence (Chester LabNet, 1996). 

• 70-year cancer risk at PM10 = 45 μg/m3 (Keeler annual average from 1993-2000). 

3.5 VISIBILITY AND SENSITIVE AIRSHEDS 

Under normal conditions, visibility in the Owens Valley generally ranges from 37 to 93 miles, 

with the best visibility occurring during winter. Visibility is most limited from May through 

September and during days when Owens Lake dust storms occur. Owens Lake dust storms can 

reduce visibility to near zero at Owens Lake and obscure visibility 150 miles away from the lake 

bed. The main cause of visibility degradation in the Owens Valley is fine particles in the 

atmosphere. In addition to dust from Owens Lake, visibility degradation results from transport of 

air pollutants from the San Joaquin Valley and South Coast air basins, and from forest fires. 

Most of the visibility degradation can be attributed to inter-basin transport of air pollutants. On 

days when Owens Lake dust storms do not occur, emissions of fine particulate matter from 

gasoline and diesel fueled vehicles and equipment within the Owens Valley are local man-made 

contributors to visibility degradation. However, these local sources have an insignificant impact 

on the area’s visibility. Nitrogen dioxide, a light-absorbing gas formed during local fuel 

combustion, contributes less than five percent to the overall visibility degradation. Other local 

man-made sources of visibility degrading emissions represent less than five percent of the 

overall reduction in visibility (Trijonis, et al., 1988). 

There are 11 sensitive airsheds in the region, including wilderness areas, national parks, national 

forests, a national historic site, and the R-2508 military airspace. Figure 3.7 shows the locations 

of these sensitive airsheds. Four of these airsheds are designated as Class I PSD (Prevention of 

Significant Deterioration) areas, which are afforded more stringent protection from visibility 

degradation and for impacts from air pollutants: John Muir and Domeland Wilderness Areas, 

Kings Canyon and Sequoia National Parks. These sensitive areas and their classifications are 

shown in Table 3.5. 

The R-2508 military air space, which includes the China Lake Naval Air Weapons Station, is a 

sensitive site for visibility impacts from Owens Lake dust events. Good visibility is needed for 

some military operations, such as an air-to-air test (an air-launched target whose target is also in 


	 	 


  
 	



   	
   
                         



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Table 3.5 – Sensitive airsheds and their PSD classifications.

Sensitive Airshed PSD Airshed

Classification

* Wilderness Areas in National Forests:

Domeland Class I

Golden Trout Class II

John Muir Class I

South Sierra Class II

* National Parks:

Death Valley Class II

Kings Canyon Class I

Sequoia Class I

* National Historic Site:

Manzanar Class II

* National Forests:

Inyo Class I&II

Sequoia Class I&II

* Military Base:

China Lake NAWS Class II

Source: MHA Environmental Consulting, Inc., 1994.
Air Quality Setting 

the air), which relies on high-speed cameras to record time and position information. Owens 

Lake events can reduce the visibility to less than one to two miles at China Lake. The 

Department of the Navy has stated that cancellation of a test costs the Range and/or its customer 

approximately $10,000 to $50,000. Owens Lake dust events can lead to cancellations of several 

tests per day and can last for one to two days, or occasionally longer (Stevenson, 1996). 

3.6 OFF-LAKE PM10 VIOLATIONS 

Analysis of exceedances of the PM10 NAAQS at Owens Lake shoreline monitors indicates that 

some of the high PM10 days would have resulted in exceedances, even if emissions from the lake 

bed were reduced to zero (Kiddoo, et al., 2007). Winds from off-lake directions carry windblown dust from the Keeler dunes, northeast of the lake bed, and from the Olancha dunes, south 

of the lake bed, toward shoreline monitors. In the period from January 2000 through December 

2006, the Keeler dunes are estimated to have caused five violations of the PM10 NAAQS at 

Keeler per year. In the same period, the Olancha dunes are estimated to have caused one 

violation of the PM10 NAAQS per year at each of the Shell Cut and Flat Rock monitors. At the 

Dirty Socks monitor, 30 violations can be attributed to southerly wind directions, but it appears 

that many of these violations may have resulted from erosion of emissive areas on the lake bed, 

but south of the Dirty Socks monitor. Dust controls in this area immediately south of the Dirty 

Socks monitor were completed at the end of 2006, and it is expected that violations there due to 

southerly wind directions will be reduced to levels similar to those observed at Flat Rock and 

Shell Cut (see Kiddoo, et al., 2007, for details of this analysis). 

After all the lake bed sources in the 2003 and 2008 dust control areas are controlled, the Keeler 

dunes area is expected to be the only remaining dust source that is causing exceedances of the 

standard in the planning area. The Olancha dunes are natural dunes that were present prior to the 

City’s water gathering activities in the Owens Valley. If PM10 violations are attributed to the 

Olancha dunes, these violations will be treated as natural events and a Natural Events Action 

Plan will be developed and implemented in accordance with the USEPA rule on Exceptional 

Events (see Section 2.2.3.3). 

3.7 REFERENCES 

Chester LabNet, 1996. Chester LabNet - Portland, report on chemical analysis of ambient filters, 

Report #95-085, prepared for Great Basin Unified Air Pollution Control District, Tigard, 

Oregon, June 18, 1996. 

Federal Register, 1999. Approval and Promulgation of Implementation Plans: California – 

Owens Valley Nonattainment Area; PM10, Federal Register, Volume 64, No. 171, pp. 

48305-48307, September 3, 1999. 

GBUAPCD, 1987. Great Basin Unified Air Pollution Control District, Adopted Toxic Risk 

Policy, GBUAPCD, Bishop, California, 1987. 

GBUAPCD, 1995. Great Basin Unified Air Pollution Control District, Mono Basin Planning 

Area PM10 State Implementation Plan (Final), GBUAPCD, Bishop, California, May, 

1995. 

3-9 
Air Quality Setting 

3-10 

GBUAPCD, 1998a. Great Basin Unified Air Pollution Control District, Owens Valley PM10

Planning Area Demonstration of Attainment State Implementation Plan, GBUAPCD, 

Bishop, California, November 16, 1998. 

GBUAPCD, 2003. Great Basin Unified Air Pollution Control District, Owens Valley PM10

Planning Area Demonstration of Attainment State Implementation Plan - 2003 Revision, 

GBUAPCD, Bishop, California, November 13, 2003. 

GBUAPCD, 2006b. Great Basin Unified Air Pollution Control District, Settlement Agreement 

between the District and the City to resolve the City’s challenge to the District’s 

Supplemental Control Requirement determination issued on December 21, 2005 and 

modified on April 4, 2006, GBUAPCD, Bishop, California, December 4, 2006. 

Hopkins, 1997. Hopkins, Ross, letter from National Park Service, Manzanar National Historic 

Site, Superintendent, to Ellen Hardebeck, Great Basin Unified Air Pollution Control 

District, regarding the Owens Lake air pollution problem, January 3, 1997. 

Kiddoo, et al., 2007. Kidoo, Phill, Jim Parker, Duane Ono, Off-Lake PM10 Exceedances at 

Owens Lake, January 1, 2000 – June 30, 2007. 

OEHHA, 2002. Office of Environmental Health Hazard Assessment, Air Toxics Hot Spots 

Program Risk Assessment Guidelines, Part II, Technical Support Document for 

Describing Available Cancer Potency Factors, Sacramento, California, December 2002. 

Ono, et al., 2000. Ono, Duane, Ellen Hardebeck, Jim Parker, B.G. Cox, Systematic Biases in 

Measured PM10 Values with U.S. Environmental Protection Agency-Approved Samplers 

at Owens Lake, California, J.Air & Waste Manage. Assoc., Pittsburgh, PA, 50:1144-

1156, July 2000. 

Parker, 2003. Parker, James, Comparison of TEOM and Partisol Monitors at Owens Lake, 

California, Great Basin Unified Air Pollution Control District, June 2003. 

Schade, 2005. Great Basin Unified Air Pollution Control District, Owens Lake Dust Control: Air 

Pollution Control Officer’s 2004-2005 Determination Requiring the City of Los Angeles 

to Implement, Operate and Maintain Air Pollution Control Measures on Additional Areas 

of the Owens Lake Bed, Letter from Theodore D. Schade, Air Pollution Control Officer, 

GBUAPCD, Bishop, California to Ronald Deaton, General Manager, Los Angeles 

Department of Water and Power, Los Angeles, California, December 21, 2005. 

Schade, 2006. Great Basin Unified Air Pollution Control District, Modified Determination and 

Response to the City of Los Angeles’ Alternative Analysis of the Air Pollution Control 

Officer’s 2004-2005 Supplemental Control Requirements Determination, Letter from 

Theodore D. Schade, Air Pollution Control Officer, GBUAPCD, Bishop, California to 

Ronald Deaton, General Manager, Los Angeles Department of Water and Power, Los 

Angeles, California, April 2, 2006. 
Air Quality Setting 

3-11 

Stevenson, 1996. Stevenson, C.A., letter from U.S. Department of the Navy, Naval Air Weapons 

Station, Commanding Officer, to Ellen Hardebeck, Great Basin Unified Air Pollution 

Control District, regarding impact of Owens Lake dust on China Lake, May 9, 1996. 

Trijonis, J. et al., 1988. Trijonis, John, Michael McGown, Marc Pitchford, Donald Blumenthal, 

Paul Roberts, Warren White, Edward Macias, Raymond Weiss, Alan Waggoner, John 

Watson, Judith Chow, Robert Flocchini, RESOLVE Project Final Report - Visibility 

Conditions and Causes of Visibility Degradation in the Mojave Desert of California, 

Naval Weapons Center, China Lake, California, July 1988. 

USEPA, 2007a. United States Environmental Protection Agency, Proposed Finding of Failure to 

Attain; State of California, Owens Valley Nonattainment Area; Particulate Matter of 10 

Microns or Less, EPA-R09-OAR-2007-0091, FRL-8291-1, Federal Register, Volume 72, 

No. 56, March 23, 2007, pp 13723-13726. 

USEPA, 2007c. United States Environmental Protection Agency, AirData website, 

http://www.epa.gov/air/data/monvals.html, August, 2007. 
BLANK PAGE