Coso Junction PM-10 Planning Area State Implementation Plan

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May 18, 2010:

FINAL 2010 PM10 Maintenance Plan and Redesignation Request for the Coso Junction Planning Area

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2010 Coso Junction PM10 Maintenance Plan

EXECUTIVE SUMMARY

This document is a revision to the 2004 PM10 State Implementation Plan (SIP) for the Coso Junction PM10 Planning Area. It includes 1) a request to redesignate the area from nonattainment for the National Ambient Air Quality Standard for PM10 (federal standard) to attainment based on monitoring data and a modeling analysis, and 2) a maintenance plan that contains requirements to ensure the federal PM10 standard will not be violated in the future. As required to redesignate the area to attainment, the enclosed monitoring data and modeling analysis show the Coso Junction Planning Area (CJPA) had less than or equal to 1.0 average annual exceedances of the federal PM10 standard (150 µg/m3 for a 24-hour average) during the 3-year period from January 2007 through December 2009.

The 2004 State Implementation Plan for the Coso Junction Planning Area examined the PM10 problem during the period from 1985 to 2003. During that period, 15 violations of the federal 24-hour PM10 standard were monitored at the Coso Junction rest area on Highway US 395. Thirteen of those violations were found to have been caused by windblown dust from the dry lake bed of Owens Lake that is 14 miles outside (to the north) of the Coso Junction Planning Area. In November 2004, the District adopted a SIP for the CJPA to explain how the area would be brought into attainment. Since PM10 violations at Coso Junction were primarily caused by windblown dust from Owens Lake, the Coso Junction attainment demonstration relied on implementing dust controls outside of the planning area. Under the 2003 Owens Valley PM10 SIP, windblown dust from 29.8 square miles of the dry lake bed at Owens Lake were required to be controlled by December 2006. A dispersion modeling analysis showed these dust mitigation efforts would be adequate to bring the Coso Junction Planning Area into attainment.

A review of daily ambient monitoring data from Coso Junction showed three monitored exceedances of the federal 24-hour PM10 standard (150 micrograms per cubic meter, µg/m3) during the 3-year period from January 2007 through December 2009. The federal 24-hour PM10 standard allows no more than an average of 1.0 expected exceedances per year over a 3-year period. Since daily PM10 monitor data showed the monitor site had an average of 1.0 exceedances per year, PM10 levels near the monitor site can be considered to be in attainment with the federal standard.

A closer examination of the three exceedances found that two exceedances in 2007 (6/5/2007, 217 µg/m3; 12/6/2007, 283 µg/m3) were caused by windblown dust from an unpaved truck parking area west of the PM10 monitor site. The owner of the unpaved parking area was notified and the area was graveled in 2008 and surfaced with asphalt in 2009 to control fugitive dust. The third monitored exceedance (12/22/2009, 168 µg/m3) was caused by windblown dust from Owens Lake. During that event, dust source areas at Owens Lake that were not previously identified in the 2003 Owens Valley SIP contributed to the exceedance at Coso Junction. A revision to the Owens Valley SIP in 2008 included the majority of these dust source areas as part of an additional 9.8 square miles of the lake bed that was controlled using shallow flooding in April 2010. Another 3.5 square miles of the lake bed are expected to be controlled by October 2010. Therefore, dust control measures were implemented to mitigate the causes of dust for all three PM10 exceedances at Coso Junction that took place during the 3-year attainment demonstration period.

Although daily PM10 monitor data collected at the Coso Junction rest area showed the area could be considered to be in attainment with the federal standard, higher PM10 levels are likely to have occurred at locations closer to Owens Lake, since this is the primary source of windblown dust that caused Coso Junction to be designated nonattainment. The monitor site at the Coso Junction rest area is about 18 miles south of Owens Lake, while the northern boundary of the CJPA is closer at 14 miles from Owens Lake. To determine if windblown dust from Owens Lake caused PM10 violations at the northern boundary or at other locations in the CJPA, a dispersion model was run to analyze windblown dust impacts for the 3-year period from July 2006 through June 2009. To evaluate attainment through a modeling analysis, the fourth highest value over a 3-year period must be below 150 µg/m3 at all locations. The District used the CALPUFF dispersion model, which is a guideline model recommended by the United States Environmental Protection Agency (US EPA) for long-range transport and situations where complex winds influence dispersion. As expected, the CALPUFF model showed the highest PM10 concentrations were at the northern boundary of the CJPA. The highest site had two days with modeled impacts above 150 µg/m3 and a third high concentration of 150 µg/m3. Since 150 µg/m3 is not an exceedance of the PM10 standard there were only two modeled exceedances at the highest receptor site in the CJPA. The fourth highest modeled value at the same site for the 3-year period was 137 µg/m3. Therefore, the CALPUFF model analysis demonstrated it is reasonable to believe that attainment of the standard was achieved at all locations in the planning area.

As a result of our evaluation of monitoring data and a CALPUFF modeling analysis, the District recommends through the adoption of this SIP revision that the California Air Resources Board request the US EPA redesignate the Coso Junction Planning Area from nonattainment to attainment for the federal PM10 standard.

To ensure compliance with the federal PM10 standard is maintained in future years, the District evaluated future activities that could affect PM10 levels in the planning area and the adequacy of existing rules, policies and emission control requirements to control emissions from those sources and activities. District staff found that existing rules for fugitive dust and new source review were adequate to control potential new sources within the Coso Junction Planning Area. For PM10 sources outside the planning area, the major concern is for windblown dust from Owens Lake. District staff believes the control strategy and contingency requirements in the 2008 Owens Valley PM10 SIP are adequate to protect air quality in the Coso Junction area. Therefore, no additional contingency measures will be needed to ensure future compliance with the federal PM10 standard in the Coso Junction Planning Area.

Tables from FINAL 2010 PM10 Maintenance Plan and Redesignation Request for the Coso Junction Planning Area below:

Table 1. Summary of PM10 exceedances monitored over 150 μg/m3 in the Coso Junction Planning
Area and concentrations at other sites on the same day. See Table 2 for causes of exceedances
in the CJPA for the dates shown below and Appendix B for hourly meteorological data for these
events.

24-Hour Average PM-10 Concentrations (ug/m3)

Coso Junction Planning Area Indian Wells Valley Owens Valley Planning Area
Exceedance Coso   Pearson- Ridge- Inyo-     Lone Dirty Flat Shell
Date Junction Navy ville crest kern Keeler Olancha Pine Socks Rock Cut
4/25/1985 307             92      
4/2/1986 1175             95      
6/7/1986 157             44      
1/15/1987 196         100   25      
2/3/1989 227 101       1861   126      
4/23/1990 866 94         200        
10/26/1993 254   131 16 59 112 346        
12/23/1993 188   50 18 9 412 185 58      
1/5/1994 388   239 75   199 365 76      
4/8/1995 692   392 235   158 128 107      
4/9/1995   567       331 2252 52      
4/21/1995 337 268       51 119 16      
4/27/1996 50 18 176 92 81 65 657 28      
5/23/1996 309   132 31 79 259 42 34      
3/6/1998 91 246       305 33 42      
3/18/1998 409 49       46 228        
7/25/2002 175    
36
  87 71 64 75 100 90
2/2/2003 484    
162
  484 1062 116 10933 395 9162
12/28/2006 296    
  2101 428 126 104 735 94
6/5/2007 217    
35
  159 55 71 68 508 182
12/6/2007 283         13 38 15 29 10 16
12/22/2009 168         236 76 42 17 217 34

Table 2. Over the last 25 years, violations of the federal PM10 standard in the Coso Junction
Planning Area were primarily caused by dust from the Owens Lake area. See Table 1 for PM10
concentrations on the dates shown below and Appendix B for hourly meteorological data for
these events.

Exceedance Date
Maximum Hourly Wind
COMMENTS
Max Speed Direction
MPH @ 10 m Degrees
4/25/1985 30.0 335 N wind all day, Owens Lake Dust, Coso Met Data
4/2/1986 37.5 350 N wind all day, Owens Lake Dust
6/7/1986 27.5 315 Variable winds during day, Owens Lake Dust
1/15/1987 40.0 35 N wind all day, Owens Lake Dust
2/3/1989 38.0 285 Variable winds during day, Owens Lake Dust
4/23/1990 26.0 272 Abandoned Ag Land Dust
10/26/1993 29.3 18 N wind all day, Owens Lake Dust
12/23/1993 25.7 35 N wind all day, Owens Lake Dust
1/5/1994 31.0 22 Variable winds during day, Owens Lake Dust
4/8/1995 23.2 316 Coso Junction Met, Owens Lake Dust
4/9/1995 35.9 358 Coso Junction Met, Owens Lake Dust
4/21/1995 29.2 7 N wind all day, Owens Lake Dust
4/27/1996 26.0 38 N wind all day, Owens Lake Dust
5/23/1996 30.7 5 N wind all day, Owens Lake Dust
3/6/1998 34.9 354 Variable winds during day, Owens Lake Dust
3/18/1998 12.0 48 Variable winds during day, Owens Lake Dust
7/25/2002 17.6 163 McNalley Fire smoke
2/2/2003 36.2 3 N wind all day, Owens Lake Dust
12/28/2006 46.8 337 N wind all day, Owens Lake Dust
6/5/2007 36.2 264 W wind, Coso Junction Parking Area Dust
12/6/2007 42.6 252 W wind, Coso Junction Parking Area Dust
12/22/2009 39.1 1 N wind, Regional and Owens Lake Dust

Table 3. The expected number of exceedances per year has decreased since dust control
measures were implemented on 29.8 square miles of the Owens Lake bed in December 2006.

  PM10 Concentrations (µg/m³) Number Adjusted Number
  Annual 3-Year Peak of # of Sample
Year Average Average 24-Hour Exceeds Exceeds Days
1985 Invalid   307 1   49
1986 51.51   1175 2 12 58
1987 33.62   196 1 6 59
1988 22.12 35.75 92 0 0 59
1989 27.50 27.74 227 1 6 61
1990 29.37 26.33 866 1 6 60
1991 18.80 25.22 93 0 0 60
1992 Invalid   38 0   36
1993 28.78   254 2 12 59
1994 16.69   388 1 6 61
1995 32.28 25.92 692 2 12 58
1996 Invalid   309 1   51
1997 Invalid   92 0   54
1998 23.31   409 1 6 59
1999 14.84   46 0 0 114
2000 15.02 17.72 74 0 0 110
2001 11.88 13.91 100 0 0 122
2002 18.04 14.98 175 1 3 115
2003 20.54 16.82 484 1 3 121
2004 14.89 17.82 66 0 0 121
2005 18.24 17.89 97 0 0 119
2006 20.72 17.95 296 1 1 273
2007 19.91 19.62 283 2 2 363
2008 18.63 19.75 137 0 0 366
2009 18.59 19.04 168 1 1 362

Table 4. Daily PM10 emissions inventory for the Coso Junction Planning Area for 2008 through
2025. For the purpose of the maintenance plan, no significant growth is expected in the
emissions inventory through the year 2025.

Daily PM10 Emissions for 2008 through 2025
Stationary Sources Pounds/day
California Lightweight Pumice 167
China Lake Naval Air Weapons Station 84
Coso Operating Company 953
Halliburton Services 20
Twin Mountain Rock 58
   
Area Sources
Unpaved Roads 83
Paved Roads 101
   
Mobile Sources
On]Road Motor Vehicles 12
Total PM10 (pounds per day) 1,478

Table 5. Existing District rules and regulations to control sources of PM10

Rule

Description

209-A Requires new sources with PM10 emissions greater than 250 pounds per day of total suspended particulates, or facility modifications of greater than 15 tons per year of PM10 to apply Best Available Control Technology to control PM emissions.
400 Limits visible emissions from any source, except those exempted under Rule 405, to less than Ringelmann 1 or 20% opacity.
401 Requires that reasonable precautions be taken to prevent visible particulate emissions from crossing the property boundary.
402 Prohibits sources of air pollution from causing a nuisance to the public or endangering public health and safety.
408 Limits agricultural burning operations to designated burn days and requires a burn permit.
409 Limits range improvement burning to designated burn days and requires that a burn plan be approved by the APCO.
410 Limits forest management burning to designated burn days and requires that a burn plan be approved by the APCO.
411 Limits wildland management burning to designated burn days and requires that a burn plan be approved by the APCO.
Reg. XII Requires that federal actions and federally funded transportation-related projects conform to SIP rules and that they do not interfere with efforts to attain federal air quality standards.

Reg. XIII Requires that federal actions and federally funded projects conform to SIP rules and that they do not interfere with efforts to attain federal air quality standards.




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