GREAT BASIN UNIFIED AIR PO LLUTION CONTROL DISTRICT

AIR QUALITY MAINTENANCE PLAN A ND PM10 REDESIGNATION REQUEST FOR THE TOWN OF MAMMOTH LAKES A ND REVISIONS TO DISTRICT RULE 431 – PARTICULATE EMISSIONS

ADOPTED MAY 5, 2014

ENCLOSURE 4
Adopted Air Quality Maintenance Plan and PM10 Redesignation Request for the Town of Mammoth Lakes and Revisions to District Rule 431 – Particulate EmissionsMammoth Lakes AQMP



# 2014 Update



# AIR QUALITY MAINTENANCE PLAN AND REDESIGNATION REQUEST for the Town of Mammoth Lakes

May 5, 2014Mammoth Lakes AQMP



## 2014



## AIR	QUALITY MAINTENANCE	PLAN	AND REDESIGNATION	REQUEST for	the Town	of	Mammoth	Lakes

Prepared	for	the

PM‐10	State	Implementation	Plan

By The	Town	of	Mammoth	Lakes	and The	Great	Basin	Unified	Air	Pollution	Control	District

Authors William	Taylor,	Duane	Ono,	and	Jen	Daugherty

Contributors Phil	Kiddoo	and	Megan	RybackiMammoth Lakes AQMP

iii Mammoth Lakes Air Quality Maintenance Plan and Redesignation Request 2014

Executive Summary ................................................................................................... v

Chapter 1 In troducti on ................................................................................................ 1 Chapter 2 1990 AQ MP Summa ry ............................................................................... 6 Chapter 3 Federal and St ate Air Quality Standards fo r Particulate Matter ............... 11 Chapter 4 Air Q uality Data ........................................................................................ 13 Chapter 5 Emissions Inventor y ................................................................................. 17 Chapter 6 Recept or Modeli ng ................................................................................... 23 Chapter 7 Contro l Measures .................................................................................... 28 Chapter 8 Maintenance Demonstrat ion .................................................................... 36 Chapter 9 Contingency Pl an and Maintenance Measures ........................................ 43 Chapter 10 Transportati on Conformi ty ....................................................................... 46 Chapter 11 General Conformity .................................................................................. 48 Chapter 12 Redesi gnation Req uest............................................................................ 49 Chapter 13 Refe rences .............................................................................................. 50

List of Figures

Figure ES-1 Design Day Projection for High Residential Wood Combustion Day.......... xi Figure ES-2 Design Day Projection for High Road Dust Day ........................................ xii Figure 1-1 Mono County, CA boundary and Mammoth Lakes Vicinity ........................ 3 Figure 1-2 Mammoth Lakes Planning Area ................................................................. 4 Figure 4-1 Mammoth Lakes PM-10 Quarte rly Peaks and Averages (1990-2013)......15 Figure 4-2 Mammoth Lakes PM- 10 Winter Season Peaks and Averages ( 1990-2013) ............................................................................. 16 Table 7-2 Vehicle Miles Traveled (VMT) Comparison .............................................. 35 Figure 8-1 Design Day Projection for Hi gh Residential Wood Combustion & Road Dust Da ys ................................................................................................ 40 Figure 8-2 Design Day Projection for Hi gh Residential Wood Combustion Day ....... 41 Figure 8-3 Design Day Projection for High Road Dust Day ....................................... 42

List of Tables

Table ES-1 Summary of Peak 24 hour PM-10 Emissions (kg/day) 2012 ..................... vii Table ES-2 Peak 24-hour PM-10 Emissions (kg/day) ................................................... ix Table ES-3 Forecasted PM-10 Design Da y Concentrations for High Residential Wood Combusti on Day .............................................................................. xi Table ES-4 Forecasted PM-10 Design Day C oncentrations for High Road Dust Day . xii Table 2-1 Summary of PM-10 Air Qua lity Standard Violations for the Town of Mammoth Lak es 1990-2012 ................................................................ 10 Table 3-1 National Ambient Air Qua lity Standard for Part iculates ............................ 11 Table 3-2 California Ambient Air Q uality Standard for Pa rticulates .......................... 12Mammoth Lakes AQMP

iv Table 4-1 PM-2.5 Monitoring Results ....................................................................... 14 Table 5-1 Residential Wood Bu rning Device Count ................................................. 18 Table 5-2 Amount of Wood Bur ned Annually in Homes with Wood Combustion Devices ................................................................................ 18 Table 5-3 Annual PM-10 Estimates fo r Residential Wood Combustion ................... 19 Table 5-4 Peak 24-Hour Emission Estimate s for Residential Wood Combustion .... 20 Table 5-5 24-Hour Road Dust Emissi ons ................................................................. 21 Table 5-6 Permitted Particulate Matter Sources Within the Mammoth Lakes AQMP .......................................................................................22 Table 5-7 Summary of Peak 24-Hour PM-10 Emissions (k g/day) 2012 ................... 22 Table 6-1 Dates with onl y PM-10 Filt ers .................................................................. 24 Table 6-2 Dates with PM-10 and PM-2.5 F ilters ...................................................... 24 Table 6-3 CMB Attribution Result s and Performance Statisti cs ............................... 26 Table 6-4 CMB Percent Contributi ons by Road Dust and Residential Wood Combustion 1987-88 and 2003-2011 Data Se ts ........................... 26 Table 7-1 Change in Peak 24-H our Emissions 1990-2012 ...................................... 33 Table 8-1. Peak Roadway Emi ssions Per Day 2012-2030 ....................................... 36 Table 8-2. Peak Residential Wood Co mbustion Emissions Per Day 2012-2030 ...... 37 Table 8-3. Peak Winter 24-hour PM-10 Emissions for Planning Area ...................... 37 Table 8-4. Four Highest Monitored P M-10 Concentrations at Gateway Center, Mammoth Lakes, CA (2010-1012 ) ........................................................... 38 Table 8-5 Future PM-10 Concentrations for RWC and Road Dust Days ................. 40 Table 8-6 Forecasted PM-10 Concentrations by Source for High Road Dust Day .. 41 Table 8-7 Forecasted PM-10 Concentrati ons by Source for High Residential Wood Combusti on Day ............................................................................ 42

Appendices

Appendix A Glossary Appendix B Residential Wood Burning Survey 2013 Summary Appendix C Town of Mammoth Lakes M unicipal Code Chapter 8.30 (Revised) Appendix D VMT Estimates for Days of Air Quality Monitoring – 2003 to 2011 (LSC, 2013) Appendix E Mammoth Lakes Vehicle Miles Traveled Analysis (LSC, 2012) Appendix F Mammoth Lakes Vehicle Miles Tr aveled Analysis – Comparison with 1990 Study (LSC, 2012) Appendix G Chemical Anal ysis of PM10 and PM2.5 Filters from Mammoth Lakes (DRI, 2013)Mammoth Lakes AQMP

v EXECUTIVE SUMMARY

Introduction

This document is a revision to the 1990 Ai r Quality Management Pl an (AQMP) for the Town of Mammoth Lakes. It includes 1) a request to redesignate the area from nonattainment for the National Ambient Ai r Quality Standard fo r PM10 (NAAQS) to attainment based on monitoring data and a modeling analysis, an d 2) a maintenance plan that contains requirements to ensure the f ederal PM10 standard will not be violated in the future.

Background

From 1985 to 1990, monitoring in Mammoth Lakes by the Great Basin Unified Air Pollution Control District (GBUAPCD) recorded 10 violati ons of the federal 24-hour PM10 standard. Since monitoring was on a once every six day cycle, extrapolation of the data predicted 11.2 expected violations of the NAAQS per year.

In response to the violations of the NAAQS, and determination by t he EPA that the Town of Mammoth Lakes was non-attainment for the federal PM-10 standard, the Town of Mammoth Lakes (Town) and the GBUAPCD fo rmed an ad hoc air quality committee. The committee investigated potential control stra tegies to be included in new particulate emissions regulations for the To wn. Multiple potential contro l strategies were evaluated resulting in a recommendation to the Town of Mammoth Lakes Town Council. On November 30, 1990, the Town Counc il adopted the reco mmended measures. Implementation of the adopted measures resulted in an immediate decline in PM-10 levels in the planning area, and since 1994, despite continued community growth, there have been no further excee dences of the NAAQS.

This Air Quality Maintenance Plan and Redes ignation Request is an update to the 1990 Air Quality Management Plan for the Town of Mammoth Lakes. This plan reviews the background of the 1990 plan, the measures implemented as a re sult of that plan and their effectiveness, and changes to clean air regulati ons since the adoption of the 1990 plan. This plan then recommends maintenance m easures and requests that the Town of Mammoth Lakes be redesignated as attainm ent for the federal PM-10 standard.

PM Standards

PM-10 stands for particulate matter less t han 10 microns in diameter. The National Ambient Air Quality St andard (NAAQS, or federal standard) for PM-10 was set July 1, 1987 at 150 micrograms per cubic meter ( μ g/m3) for the 24 hour standard. Levels for the PM-10 standard were selected to protect the health of people who may be sensitive to exposure to airborne parti culate matter (OAQPS 2005).

The state 24-hour average PM- 10 standard is set at 50 μg/m 3 . Violations of the state standard have also declined significantly sinc e the adoption of the AQMP. The number of monitored state standard violatio ns was as high as 56 days in 1993. Over the last fourMammoth Lakes AQMP

vi years (2009-12) the number of state standard violations has ranged from four to 31 per year.

Area Description and Population

The Town of Mammoth Lakes is located on the eastern slopes of the Sierra Nevada mountains at an elevation of 7,861 feet (2,396 m). The To wn was incorporated in 1984 and has grown from a permanent population of 4,785 in 1990 to 8,234 in 2010. Included in the Town boundaries is Mamm oth Mountain ski area which attracts about 1.2 to 1.5 million skiers each winter. During major winter weekends there are about 35,000 people in Mammoth Lakes. It is anticipated this figure will grow to about 45,000 to 52,000 people by 2025 (Town of Mammoth Lakes, 2007a).

Need for a Plan Update

In the 23 years since the adoption of the 19 90 AQMP, the conditions affecting PM-10 in Mammoth Lakes have changed significantly. This AQMP update addresses improved air quality in Mammoth Lakes; a revised General Plan for the Town of Mammoth Lakes; updated traffic modeling for the Town; an updated chemical mass balance study; revisions to the GBUAPCD Rules; and a r equest to have Mammoth Lakes redesignated as attainment for the federal PM-10 standard.

1990 AQMP Summary

In 1987, the Town and the Great Basin Unified Air Pollution C ontrol District (APCD) began developing a plan to reduce air pollution from fireplaces, woodstoves and dust caused by vehicles traveling on roads tr eated with volcanic cinders.

The AQMP relied on controlling wood smoke by replacing old wood stoves and fireplaces with cleaner wood burning appliances and cu rtailing wood burning on days that could violate the air quality standard. The Town reduced road du st emissions by using vacuum street sweepers to remove volcanic cinders soon after the roads dried and through promotion of increased transit usage. After adoption of the AQMP, monitored air pollution levels dropped significantly in Mammoth Lakes.

PM-10 and Data Summary

Based on airborne pollutant an d meteorological monitoring conducted at the Gateway Center (also known as the Rite Aid/Do-It Yourself shopping center) in Mammoth Lakes, the Mammoth Lakes Planning Area has not exceeded the feder al 24-hour NAAQS since 1994. In 1990 when the AQMP was adopted, three exceedenc es were recorded. Since then, only two exceedances of the 24-hour NAAQS were recorded – one in 1991 and one in 1994.Mammoth Lakes AQMP

vii Emissions Inventory

The emissions inventory section describes the PM-10 emission estimates for residential wood combustion (RWC), resuspended road dus t, cinders, mobile source tailpipe emissions and point sources. The methodology and data used to determine emissions is discussed for each source type. Because Mammoth Lakes exceeds the state 24-hour PM-10 standard, the emissions inventory is estimated fo r a peak 24-hour period.

Woodburning and resuspended road dust comprise almost all the PM-10 emissions during the winter. Motor vehicle exhaust, ti re wear industrial sources contribute only approximately 1.4% of the ar ea wide inventory. Estimate s for the annual and 24-hour PM-10 emissions are calculat ed for wood burning and road dust. The annual residential wood combustion emissions estimates, whic h are based on survey data, provide good information to improve the estimates for the peak 24-hour period. The PM-10 emission estimate for resuspended road dust is based on the AP-42 methodology for estimating reentrained road dust emissions from paved roads (EPA, 2013).

The current total PM-10 emissions on a peak winter day in the Town of Mammoth Lakes are 3,385 kg/day in the Town of Mammoth Lakes and 4,324 in the entire nonattainment area boundary, see Table ES-1. A distinction is made for the in-Town emissions inventory that was used for Chemical Mass Balanc e receptor model and the maintenance demonstration, as opposed to the inventory for the larger nonatta inment area. The inventory for the larger nonattainment area included emissions from road dust, motor vehicles and industrial sources fr om areas east of the Town that did not contribute to high PM-10 levels monitored in the Town. It is al so important to refer to the In-Town emissions inventory when making any comparisons to the analysis in the 1990 Air Quality Management Plan for the Town of Mammot h Lakes, which was based on In-Town emissions.

Table ES-1 Summary of 24-hour PM-10 Emissions (kg/day) 2012

Source In Town of Mammoth Lakes Nonattainment Area Total Residential Wood Combustion 850 850 Resuspended Road Dust & Cinders 2,522 3,455 Tailpipe, Tire and Brake Wear 9 11 Industrial Sources 4 8 Total 3,385 4,324

Chemical Mass Balance Results

The Desert Research Institute of Reno, Nevada (DRI) conducted a chemical mass balance (CMB) study for Mammoth Lakes in 2013. Chemical sour ce profiles, or fingerprints, were taken from the 1990 AQMP. The sources profiled were:Mammoth Lakes AQMP

viii  Mammoth Lakes road cinder storage

 Mammoth Lakes paved road dust

 idling diesel ski tour buses in Mammoth Lakes

 fireplace burning a typical Mammoth Lakes wood mix

 a Fisher woodstove with ty pical Mammoth Lakes wood mix

CMB model version 8 (USEPA) was used to esti mate source contributions to PM-10 and PM-2.5 for days with chemically speciated data. For the winter 1987-1988 study (Ono et al, 1990), on average, fireplac es contributed 75% of the PM-10 and road dust 25%. Table 6-4 compares the results of the 1987-88 study to this study. Three of the days in the 1987-88 study showed wood smoke contributing >95% of the PM-10; the current study shows no high PM-10 days with greater than 75% of the PM-10 cont ributed from wood smoke (DRI, 2013). The CMB study found t hat since the adoption of the 1990 AQMP, peak PM-10 impacts from wood smoke and road dust have both dropped by about 33%. (DRI, 2013).

Control Measures

In December of 1990, the Town of Mammo th Lakes adopted the Air Quality Management Plan (AQMP) for the Town of Mammoth La kes. The 1990 AQMP relied on controlling wood smoke by replacing old wood stoves and fireplaces with cleaner wood burning appliances and curtailing wood bu rning on days that could viol ate the air quality standard. The Town reduced road dust emissions by us ing vacuum street sweepers to remove volcanic cinders applied for traction control dur ing icy conditions soon after the roads dried and by limiting future VMT growth. C ontrol measures were adopted by the Town of Mammoth Lakes as Municipal Code Chapter 8.30, Particulat e Emissions Regulations. Major controls in the Chapter 8.30 regulations were:

 Replacement or removal of existing uncertified residential wood combustion appliances at the time of sale of a property;

 Limit the maximum number of residentia l wood combustion appliances in new construction to one certified applianc e plus one pellet fueled appliance;

 Institute voluntary and mandator y wood burning curtailment days;

 Implement a public ed ucation program;

 Implement a vacuum st reet sweeping program; and

 Limit peak VMTs to 106,600.

With the implementation of t he control measures from t he 1990 AQMP, PM-10 levels in Mammoth Lakes declined significantly. The 1990 AQMP estimated 4,259 kg/day of PM10 for the peak 24-hour period and forecast 8, 036 kg/day for the peak 24 hour total PM10 emissions in the Town by 2005 absent any controls (Ono et al. 1990). The updated emissions estimate shows 3,385 kg/day PM- 10 in 2012, which is a 20% reduction in emissions since 1990 when the AQMP was adopted. This reduction was achieved despite a 72% population increase from 4, 785 in 1990 to 8,234 in 2010. Table ES-2 shows the peak 24-hour PM-10 emissions in ventory for Mammoth Lakes in 1990 when the AQMP was adopted, the cu rrent inventory in 2012, and the projected emissionsMammoth Lakes AQMP

ix inventory in 2030 after the town has reached its buildout population and visitor numbers. The emissions inventory projections for 2030 are based on current control measures for residential wood combustion and on a change to the peak daily traffic volume limit derived from the modeling analysi s that was performed fo r this plan update.

Table ES-2 Peak In-Town 24-hour PM-10 Emissions (kg/day)
Source Category 1990 2012 2030
Residential Wood Com bustion 1,839 850 802 Road Dust and Cinders 2,390 2,522 3,143 Tailpipe, Tire & Brake Wear 23 9 11
Industrial Sources 1 4 4 Total 4,253 3,385 3,960

Amendments to Control Measures

Most of the changes to the im plementing regulations of the Town of Mammoth Lakes MC 8.30 revise outdated sections or make non- substantive technical edits. The three meaningful amendments are:

 Section 8.30.040 B. This se ction is modified to clarif y that no new wood burning appliances may be installed in multi-family developments. Prohibition of new wood burning appliances in multi-fa mily projects has been the policy of the Town. The proposed revision formalizes that prac tice and implements General Plan Policy R.10.3.

 Section 8.30.080, Mandator y Curtailment. This section has been modified to include all wood burning applia nces, except pellet stoves, in the no-burn day program. Currently, EPA cert ified stoves are exempt ed under Town regulations, but are required to participate und er the District regulations.

 Section 8.30.100 B. This se ction sets a limit for vehicle miles traveled (VMT) within the town. The current lim it is one hundred six thousa nd six hundred (106,600) VMT on any given day. Proposed developm ent projects and other Town approved activities which affect vehicle trips are ev aluated against this limit. A revised traffic model for the community incorporates additional roadway segments and revises VMT projections based on updated tr affic counts and current modeling technologies. It shows an estimated VM T at General Plan bui ldout of one hundred seventy nine thousand sev en hundred eight (179, 708) for the revised model roadway segments. The air quality modeling s hows that this overall level of traffic will not cause an exceedence of the NAAQS and is suggest ed as the VMT limit for the AQMP.Mammoth Lakes AQMP

x Maintenance Demonstration

The AQMP evaluates the effe cts of increased popul ation and visitors on PM-10 emissions and forecasts the resulting c hange in the ambient PM-10 des ign concentration. Receptor modeling results were used with the revised emissions inventory (Table ES-2) that reflected changes in permanent and visitor popul ations and the adopt ed control measures to forecast changes in ambient PM-10 concentrations.

The 2007 Town of Mammoth Lakes General Plan evaluated population in terms of People at One Time (PAOT). PAOT is the number of people in town on a peak winter Saturday and includes both residents and visitors. PAOT is expected to grow from 34,265 in 2007 to 52,000 in 2025. 2025 was considered the build out year by the General Plan. The buildout number from the General Plan has been used as the year 2030 projected population in both the RWC and VM T analyses. This provides supporting information for an analysis to demonstrate that the PM-1 0 standard can be maintained in Mammoth Lakes for at least a 10-year period. This 10-year maintenance demonstration is required under the Clean Air Act (CAA) to allow th e area to be redesignated from nonattainment to attainment for PM-10.

Proportional Rollback Analysis for Control Measure Evaluation

The effect of PM-10 emissions increas es or decreases on the ambient PM-10 concentration can be determined by using a linear rollback method of calculation. This method is based on the assumpti on that the ambient concentra tion due to a given source is proportional to the emissions from that source. The e ffect on the design day PM-10 concentration was used to evaluate the overall effect on future ambient PM-10 levels. The design day concentration, which is the statis tical fourth highest daily PM-10 concentration over a three-year period, was used for PM-10 forecasts because it is the value used by the EPA to determine compliance with the f ederal PM-10 standard. Based on PM-10 data collected over the last three years (2010-12), the four th high PM-10 concentration, and therefore the PM- 10 design day concentration, is 99 μg/m 3

.
As was described in the 1990 AQMP, Mammo th Lakes’ air pollution episodes are characterized by two different scenarios. One with high wood smoke contributions and one with high road dust contributions. The proportional roll-back analysis tested both cases. Using the peak wood smoke and peak road dust and cinders days, Tables ES-3 and ES-4 show the expected P M-10 emissions and concentrations due to growth with continued implementation of existing controls . These results show that with current control measures, growth could result in a 1% to 6% increase in the design day ambient PM-10 concentrations over the next 15 year s. Since buildout conditions under the General Plan are expected to be sustained beyond 2030, PM-10 projections for 2050 are the same as for 2030. These PM-10 forecasts are also shown graphi cally in Figures ES1 and ES-2.Mammoth Lakes AQMP

xi Table ES-3. Forecasted PM- 10 Design Day Concentrati ons for High Residential Wood Combustion Day Source Category 1990 2012 2030 2050
Background 5 μg/m 3 5 μg/m 3 5 μg/m 3 5 μg/m 3
Road Dust 5 μg/m 3 23 μg/m 3 29 μg/m 3 29 μg/m 3

Residential Wood Combustion 195 μg/m 3 71 μg/m 3 66 μg/m 3 66 μg/m 3

Vehicles* 5 μg/m 3 negligible neglig ible negligible
Industrial Sources negligible negligible negligible negligible
Total 210 μg/m 3 99 μg/m 3 100 μg/m 3 100 μg/m 3

0 50 100 150 200 250

1990 2012 2030 2050μg/m3 Figure ES-1 Design Day Projection for High Residential Wood Combustion Day

Vehicles

Residential Wood Combustion

Road Dust
Background and IndustrialMammoth Lakes AQMP

xii Table ES-4. Forecasted PM-10 Design Day Concentrations for High Road Dust Day Source Category 1990 2012 2030 2050
Background 5 μg/m 3 5 μg/m 3 5 μg/m 3 5 μg/m 3
Road Dust 93 μg/m 3 37 μg/m 3 46 μg/m 3 46 μg/m 3
Residential Wood Combustion 112 μg/m 3 57μg/m 3 54 μg/m 3 54 μg/m 3
Vehicles* negligible negligib le negligible negligible
Industrial Sources negligible negligible negligible negligible
Total 210 μg/m 3 99 μg/m 3 105 μg/m 3 105 μg/m 3

* Vehicle tailpipe and brake wear emission amount to less than 0.3 μg/m 3 except for the 1990 RWC case.

0 50 100 150 200 250

1990 2012 2030 2050μg/m3 Figure ES-2 Design Day Projection for High Road Dust Day

Vehicles

Residential Wood Combustion

Road Dust
Background and IndustrialMammoth Lakes AQMP

xiii Contingency Plan and Maintenance Measures

The analysis in this Plan shows that the adopted control measures for the Town of Mammoth Lakes are sufficient to maintain compliance with the NAAQS for PM-10 with a substantial buffer in the event that the measures do not fully achieve the same level of PM-10 reduction going forward that has been ac hieved to date. The Plan indicates a future PM-10 level of 105 μg/m 3 on a high road dust day (Table ES-4). This is 45 μg/m 3 (30%) lower than t he NAAQS of 150 μg/m 3

. The success of the existing control measures demonstrates that PM-10 levels have been reduced and will be reduced to a sufficient degree that contingency measures are not required. Nonetheless, additi onal measures have been incor porated into the AQMP to assist in further reductions of PM-10 levels with the goal of improved compliance with the California Ambient Air Qua lity Standard for PM-10. These measures include amending the Town of Mammoth Lakes Particulate Emissions Regulations to match GBUAPCD Rule 431, requiring all wood bu rning fireplaces and stoves, whether certified or not, to comply with no-burn days.

The District will continue to maintain monitori ng network integrity and, with the Town, will continue to monitor PM-10 in order to (1) veri fy the attainment stat us of the area as required by the US EPA (CAA Sec 175A, Calc agni, 1992) and (2) to implement the no burn day program, which relies on daily PM-10 monitoring. Although t he intention is to continue monitoring indefinitely in order to implement the no burn day program, the Town and the District will commit to continue ambient PM-10 monitoring for at least 20 years following the redesignation of the area to atta inment in order to comply with CAA Sec 175A(b).

The US EPA requires areas to track the progress of main tenance plans. (Calcagni, 1992) This would include updating t he emissions inventory, assessi ng air quality trends and reevaluating modeling assumptions. The Town and the District will commit to submitting progress reports every third year starting in 2017 to track the progress of the maintenance plan. Progress reports will in clude an update on PM-10 air quality, a revised peak daily emission inventory for all s ources in the planning area, a reassessment of the modeled air quality trend using the modeling assumptions in Section 8.3, and addi tional information that may be relevant to the air quality program in the Town.

Section 175A of the Clean Air Act requires that maintenance plans include contingency provisions to assure that any air quality vi olation of the NAAQS that occurs after the redesignation of the area as atta inment is promptly correct ed. As per guidance provided by the US EPA, (Calcagni, 1992) the maintenanc e plan should identify the measures to be adopted and a schedule and procedures for ac tion. This plan takes a two-tiered approach to address contingency measures; 1) to adopt additional measures with this plan to strengthen existing rules and to prevent NAAQS violations, and 2) to commit to adopt additional measures if the standard is viol ated in the future.

If a monitored violation of t he federal PM-10 standard occurs in the Town of Mammoth Lakes or the surrounding nonattainment area, the Town and the District will investigateMammoth Lakes AQMP

xiv the cause of the violation(s) . Violation days would exclude days that are considered to be exceptional events, such as high PM-10 due to smoke from wildfires as provided for under the EPA’s Exceptional Event Rule. (72 FR 13560)

Within 18 months of the vi olation, the Town and District will adopt additional control measures needed to meet the P M-10 NAAQS. Depending on th e cause of the violation these control measures may include the following:

 Reducing the no burn day trigger thres hold from a target of 130 to 100 μg/m 3 , if residential wood smoke is found to be a significant contributor.

 Implementing measures to reduce the use of volcanic ci nders or to improve street clean up procedures on roadways during the winter, if road dust is found to be a significant contributor.

Redesignation Request

States may ask U.S. EPA to r edesignate an area “attainment” if:

 the area has monitored attainment of the air quality standard;

 the area has a fully approved St ate Implementation Plan;

 U.S. EPA has determined that the improvem ent in air quality is due to permanent and enforceable reductions in emissions;

 the state has submitted, and U.S. EPA has approved, a maintenance plan for the area; and,

 the area has met all other applicab le federal CAA requirements.

As described in Chapter 8, the Town of Mammoth Lakes last exceeded the federal PM10 24-hour standard in 1993. Attainment of the PM-10 standard is a direct result of the implementation of control meas ures by the Town as described in the 1990 Air Quality Management Plan.

The daily ambient PM-10 monitoring data co llected by the Great Basin Unified Air Pollution Control District in Mammoth Lakes demonstrates that no more than 1.0 statistical exceedances of t he NAAQS have occurred over the last three years as is required to demonstrate attainment of the federal standard. In fact, the data show that there have been no exceedanc es of the federal PM-10 standar d during the last 19 years.

Applying a proportional roll back analysis to the PM-10 present and future emissions this document demonstrates that no more than 1.0 exceedances per year would be expected through the next 20 year planning period and beyond. With continued implementation of the control measures, attain ment will be maintained.

The District finds that the Mammoth Lakes PM-10 Planning Area has attained the federal PM-10 standard and requests the Ca lifornia Air Resources B oard recommend to the US Environmental Protection Agenc y that the area be redesignate d from nonattainment to attainment with the f ederal PM-10 standard.Mammoth Lakes AQMP

1 1. Introduction

1.1 BACKGROUND

Twenty five years ago, the normally clean air in Mammoth Lakes was often polluted during the winter by wood smoke and dust. Smoke fr om wood stoves and fireplaces and dust from volcanic cinders used on roadways for trac tion control contributed to high particulate matter levels that caused violations of air quality standards. Air pollution obscured visibility in what should be an idyllic mountain setting, and it posed a health hazard to the public, especially to those that might be sensit ive to particulate matter air pollution, such as children, the elderly, and people with existi ng heart or lung problems. Poor air quality was usually associated with ca lm winter days when there was little wind to blow the pollution away. Due to these conditions, fede ral air quality standards for particulate matter were violated on about 11 days each year, a nd the US Environmental Protection Agency (EPA) required an air pollution control pl an for the Town of Mammoth Lakes.

In 1987, the EPA identified the Mammoth Lakes area as having a high probability of violating the federal PM- 10 standard (52 FR 29384). Th is designation was based on measurements of PM-10 that exceeded the standard. As a result of this Group I classification, a PM-10 State Implementation Plan (SIP) for the Mammoth Lakes area was required under the Federal Clean Air Act. The 1990 Air Quality Management Plan (AQMP) for the Town of Mammoth Lakes was dev eloped to satisfy th is requirement for a PM-10 SIP.

Implementation of the measures included in the 1990 AQMP, resulted in the PM-10 levels in Mammoth Lakes dropping significantly. The result has been no exceedences of the federal standard since 1994.

This Air Quality Maintenance Plan is an update to the 1990 Air Quality Management Plan for the Town of Mammoth Lakes. This plan reviews the background of the 1990 plan, the measures implemented as a resu lt of that plan and their effectiveness, and changes to clean air regulations since the adoption of the Plan. This plan then recommends maintenance measures and requests that t he Town of Mammoth Lakes be redesignated as attainment for the federal PM-10 standard.

1.2 PM STANDARDS AND HEALTH EFFECTS

PM-10 stands for particulate matter less than 10 microns in diameter. For comparison a human hair is about 70 microns in diameter. The National Ambient Air Quality Standard (NAAQS, or federal standard) for PM-10 was set July 1, 1987 at 150 micrograms per cubic meter ( μ g/m3) for the 24 hour st andard. Levels for the PM-10 standard were selected to help the people who may be sensit ive to exposure to airborne particulate matter. (OAQPS 2005)

Particles less than 10 microns ar e usually inhaled and retained in the deepest part of the lungs. Children, the elderly , those with cardiovascular and respiratory problems, and those with influenza are especially susceptible to increased respiratory problems andMammoth Lakes AQMP

2 illnesses due to exposure to high levels of PM-10. In addition, some PM-10 sources emit particles which contain to xic and carcinogenic compounds.

Wood smoke, which is a major contributor to the high PM-10 levels of Mammoth Lakes, includes several air pollutants aside from P M-10 that contribute to the health effects problems. These are carbon monoxide, hydrocarbons and polycyclic aromatic hydrocarbons (PAH’s). Wood burning is a major source of PAH’s which has been identified as a class of compounds cont aining carcinogens (Davis and Read 1989). Particulate matter from w ood smoke is largely composed of particles less than 2.5 microns or PM-2.5. Due to the smaller size of smoke particles, exposure to PM-2.5 poses additional health risks to sensitive populations at lower concentrations than PM-10.

1.3 AREA DESCRIPTION AND POPULATION

The Town of Mammoth Lakes is located on the eastern slopes of the Sierra Nevada mountains at an elevation of 7,861 feet (2,396 m). Figure 1-1 shows the relative location of Mammoth Lakes. The Town was in corporated in 1984 and has grown from a permanent population of 4, 785 in 1990 to 8,234 in 2010. Included in t he Town boundaries is Mammoth Mountain ski area which attracts about 1.2 to 1.5 million ski ers each winter. During major winter weekends there are about 35,000 people in Mammoth Lakes. It is anticipated this figure will grow to about 45,000 to 52,000 people by 2025 (Town of Mammoth Lakes, 2007a).

Most homes and rental units in Mammoth Lak es contain woodstoves or fireplaces. Temperature inversions during the winter s eason cause a buildup of wood smoke in the lower elevations of the town. In addition to wood smoke, particulates generated from resuspended road dust and cinders that are appl ied to roadways during snowstorms can add significantly to PM-10 levels after these roads dry. The comb ination of road dust, wood smoke and meteorological stagnations, espec ially during peak periods of the ski season, has been associated with elevated PM-10 in Mammoth Lakes.

1.4 BOUNDARIES OF THE PM-10 PLANNING AREA

The U.S. Environmental Protection Agency i dentified the boundaries in Figure 1-2 as the initial designation for the Gr oup I area or Planning Area. Through the course of the development of this document it was det ermined that the boundaries for the Town of Mammoth Lakes are more appropriate for the P M-10 Planning Area. This is justified by the lack of significant sources outside the To wn boundaries. The shrinking of the planning area boundaries is not expected to have any significant effects on the adequacy of the SIP, since all the sources affe cted by the controls discussed in the SIP are inside the Town boundaries.Mammoth Lakes AQMP

3 Figure 1-1 Mono County, CA boundar y and Mammoth La kes vicinity.Mammoth Lakes AQMP

4 Figure 1-2 Mammoth Lakes Planning AreaMammoth Lakes AQMP

5 1.5 NEED FOR PLAN UPDATE

In the 23 years since the adopt ion of the 1990 AQMP, the c onditions pertaining to PM10 in Mammoth Lakes have changed signif icantly. This AQMP update addresses improved air quality in Mammoth Lakes; a revised General Plan for the Town of Mammoth Lakes; updated traffic modeling for the Town; an updated chemical mass balance study; revisions to the GBUAPCD Rules; and a request to have Mammoth Lakes redesignated as attainment for the federal PM-10 standard.

1.5.1 Redesignation Requirements

As a result of the signific ant air quality improvements fo llowing the implementation of the 1990 AQMP, Mammoth Lakes has not ex ceeded the federal standard for PM-10 since 1994. With that success and the proj ected maintenance of air quality through adopted implementation measures , the Great Basin Unifi ed Air Pollution Control District recommends that the CARB reques t that the EPA redes ignate the Mammoth Lakes Planning Area to attainment. To be formally redesignated to attainment, the AQMP must demonstrate that:

 The area has monitored attainment of the air quality standard;

 The area has a fully approved St ate Implementation Plan;

 The U.S. EPA has determined that the impr ovement in air quality is due to permanent and enforceable reduct ions in emissions; and

 The state has submitted, and U.S. EPA has approved, a maintenance plan for the area.

This update to the AQMP fulfill s the requirements for redesi gnation. It incorporates the latest monitoring data fr om Mammoth Lakes showing t hat the Planning Area has attained the federal standard for PM-10. The Plan includes existing and proposed measures to maintain PM-10 levels below the federal NAAQS for the next 10 years and beyond. It incorporat es an updated vehicle miles traveled (VMT) analysis, residential wood combustion device invent ory, and revised community growth estimates from the 2007 Town of Mammoth Lakes General Plan.Mammoth Lakes AQMP

6 2. 1990 AQMP Summary

2.1 DEVELOPMENT OF THE PLAN

In 1987, the Town of Mammoth Lakes (Town) and the Great Basin Un ified Air Pollution Control District (APCD) began devel oping a plan to reduce air pollution from fireplaces, woodstoves and dust caused by vehicles travelin g on roads treated with volcanic cinders. The cinders were applied as an anti-skid mate rial on roads during the winter and became airborne when the roads dried. T he Town and the APCD worked with an ad hoc advisory committee representing local businesses, government agenc ies, health professionals and the general public to develop an air pollution control strategy. In 1990, this strategy was adopted as the Air Qualit y Management Plan (AQMP) fo r the Town of Mammoth Lakes. (Ono, et al. , 1990)

2.2 PLAN SUMMARY

The AQMP relied on controlling wood smoke by replacing old wood stoves and fireplaces with cleaner wood burning appliances and cu rtailing wood burning on days that could violate the air quality standard. The Town reduced road du st emissions by using vacuum street sweepers to remove volcanic cinders soon after the roads dried and through promotion of increased transit usage. After adoption of the AQMP, monitored air pollution levels dropped significantly in Mammoth Lakes.

The federal air quality standard for particulate matter is measured as PM-10 and PM-2.5, which stands for particulate matter less t han 10 microns and 2.5 microns in diameter. The AQMP was based on reducing PM-10 emissions to meet the feder al 24-hour average standard of 150 μg/m 3 . After the adoption of the AQMP in 1990, three exceedances of the federal PM-10 standard were monitored in the first y ear. Following that only one exceedance of the federal PM-10 standard was measured in 1991 and none were measured in 1992 and 1993. The last m easured exceedance of the federal PM-10 standard was monitored in 1994 (Table 2-1).

Although the federal standard for PM-10 is currently bei ng met, the more stringent California Ambient Air Qualit y Standard for PM-10 is still viol ated in the Town. The state 24-hour average PM-10 standar d is set at 50 μg/m 3 . Violations of t he state standard have declined significantly since the adoption of the AQMP. As s een in Table 2- 1, the number of monitored state standard viol ations was as high as 56 days in 1993. Over the last four years (2009-12) the number of st ate standard violations has r anged from four to 31 per year.

At the time of adoption, the Town’s wood smoke and street sweeping control measures were the most stringent in the state. Since then, other areas have recognized the success of these measures and adopted similar cont rol requirements for their areas.

PM-10 emission projections and air quality m onitoring show that the adopted wood smoke and road dust control measures succeeded in br inging the area into attainment with theMammoth Lakes AQMP

7 federal PM-10 standard. Addi tional measures; however, will be needed to meet the state PM-10 standard.

2.3 1990 CONTROL MEASURES

2.3.1 Wood Smoke

The 1990 Air Quality Managem ent Plan relied on regulations for reducing PM-10 emissions from wood smoke by limiting the number of wood burning appliances to one EPA certified woodstove per dwelling, requiring change-outs of non-EPA certified woodstoves and fireplaces upon re sale of a home or dwelling and by instituting no-burn days on days that could violat e the standard. The plan also included a public awareness program to encourage comp liance with no-burn days.

2.3.2 Wood Stove & Fireplace Change-outs

In 1990, it was estimated that there were 5,946 woodstoves and firepl aces with less than 1% of those being EPA-ce rtified. To reduce wood smoke emissions, it was required that upon resale of a property any fireplace or non-EPA certified woodstove must be replaced with an EPA Phase II certified wood stove or a pellet stove. As an alternative to replacement, non-EPA certified wood burning appliances can also be removed or otherwise rendered inoperable. .

2.3.3 Public Awareness Program.

The Town has a public awareness program to educate residents and visitors about the air pollution problem in Mammoth Lakes. Duri ng the winter, daily weather reports include a “red-yellow-green” burn day call to alert pe ople to the no-burn day status for residential wood burning. Because about 80 % of the people in town during the winter are visitors, they must be educated on a daily basis about the air pollution problem and the no-burn day program. The Town's pub lic awareness program includes:

 Daily radio and TV announcements of red, yellow or green burn days, including a no-burn day ticker on the local public access TV channel,

 Newspaper advertisement s with the (760) 934-1010 burn day status phone number,

 Newspaper articles about local air pollution and no-burn days,

 Tent cards and pamphlets for visitor rooms providing burning information, and

 Woodburning handbooks published by the California Air Resources Board.

2.3.4 No-burn Days.

No-burn days are called when a meteorological inversion and calm wind conditions could persist for a given day. The calm air prevent s the dilution and transport of air pollutants and allows PM-10 concentrations to build up in the evening fr om about 4:00 PM to midnight and then again in the morning from 6:00 to 10:00 AM. Wh en calm weather is predicted, the Town's meteor ologist may call a mandatory or a voluntary no-burn dayMammoth Lakes AQMP

8 based on the strength of the forecasted inve rsion and the population in town. The meteorologist indicates if it is a red, yellow or green burn day to let the public know if it is mandatory or voluntary no-burn day, or if it is okay to burn. Under the 1990 AQMP, appliances meeting the emissions requirement s of the EPA were exempted from the noburn days. Because 85% to 90% of the woods toves and fireplaces are now EPA certified appliances, pellet stoves, or gas appliances , only a small percentage of the wood burning appliances are now subject to the no burn days. To cont inue to achieve emission reductions, this updated AQMP removes the no burn day exemption for EPA certified appliances.

2.3.5 Traffic Related Control Measures

After winter storms, volcanic cinders are spread on the roadways in town to provide additional traction and prevent vehicles from sliding on the icy roads. These cinders are crushed into ever smaller pieces by passing v ehicles. When the roads dry, vehicles kick up fine dust from the roadway. In the 1990 AQ MP, road dust was found to contribute up to 44% of the PM-10 on days th at violated the federal air quality standard. The AQMP relies on vacuum street sweeping to remove t he cinders after the roads dry and a limit on traffic volume to prevent the problem from growing with the population. The traffic volume limit was set at 106,600 vehicle miles trav eled on any day and is regulated through the approval of new developments by the Town.

2.3.5.1 Vacuum Street Sweeping.

The Public Works Director is directed by the regulations to undert ake a vacuum street sweeping program to reduce P M-10 emissions resulting from excessive accumulations of cinders and dirt. This program has been running continuously since the adoption of the 1990 AQMP.

2.3.5.2 Traffic Volume.

The traffic volume limit in the 1990 AQMP was based on the PM-10 impact in 1990 when daily peak traffic volume was estimated at 66, 275 vehicle miles traveled (VMT). The Final Program Environmental Impac t Report (FPEIR) to suppor t the 2007 Town of Mammoth Lakes General Plan Update estimates the 2004 peak traffic volume at 74,051 VMT for 2004. The FPEIR indicated t hat unconstrained vehicle traffic could reach 128,270 VMT on peak visitor days by 2024. However, it concluded that through transportation mitigation measures included in the G eneral Plan FPEIR, VMT will not exceed the 106,600 VMT limit (Town of Mammoth Lakes, 2007b).

Since adoption of the G eneral Plan, the Town has developed a revised traffic model. This model includes additional roadw ay segments and as a result, shows a higher current and future VMT. This AQMP relies on the updated model and the revi sed VMT numbers. Currently, District rule 431 and Town Ordinanc e (8.30.110) prohibits the approval of any new development or project t hat would cause projected vehi cle traffic to exceed 106,600 VMT. The Town’s revised traffic model combined with the updated Chemical Mass Balance study will lead to am endments to these regulations. If and when it can be reliablyMammoth Lakes AQMP

9 determined that a higher VMT level may be sustained without exceeding the NAAQS, due to restrictions from other emission sources or to refined analytic inputs and/or other methodologies, then the appropr iate amendments to the Town’s Municipal Code and AQMP may be considered (Town of Mammoth Lakes, 2007b).

2.4 AIR QUALITY IMPACTS

The 1990 AQMP is based on reducing PM-10 em issions to meet the federal standard of 150 μg/m 3 for a 24-hour period. After its adoption, three exceedances of the federal PM10 standard were monitored in the first year. Following that one exc eedance of the federal PM-10 standard was measured in 1991 and none were measured in 1992 and 1993. The last measured exceedance of the federal PM-10 standard was monitored in 1994. Table 2-1 shows the actual number of monitored exceedances and the expected number of exceedances based on the proportion of sample days each year. Note that an expected number of exceedances is not ca lculated for years when the dat a capture rate is less than 75% for any quarter. (US EPA, 2014)

Although the federal standard for PM-10 is currently bei ng met, the more stringent California Ambient Air Qua lity Standard for PM-10 (50 μg/m 3 ) is still violated in Mammoth Lakes. The number of monitor ed state standard viol ations was as high as 88 in 1990, the year the plan was adopted, but has declined signifi cantly since then. Over the last four years of daily monitoring in the Mammoth Lakes (2009-12) the numb er of state PM-10 standard violations has ranged from 5 to 46 per year. (US EPA, 2014)

2.4.1 Projected PM-10 Impacts

The PM-10 analysis in the 1990 AQMP show ed that two scenarios existed that could cause violations of the feder al standard. One vi olation day was dominated by PM-10 from wood smoke (95%), with 5% from road dust, while anot her violation day was 66% wood smoke and 44% road dust. T he control strategy in the plan was designed to bring concentrations on both "design days" down to levels that would meet the standard. Chapter 6 has an updated analysis of PM-10 and PM-2.5 filter samples collected from 2003 through 2011 that shows high PM days ar e still associated with wood smoke and road dust dominated days, but at concentrations that are below the federal standards.

2.5 1990 AQMP Succeeds in Ac hieving Federal Attainment

PM-10 emission projections and air quality m onitoring show that wood smoke and road dust control measures have succeeded in bri nging the Town into attainment with the federal PM-10 standard. Furthermore, as di scussed in Chapter 8, the currently adopted control measures are expected to be sufficient to maintain compliance with the federal standard into the future. The Town has be en successful in meeting the federal PM-10 standard; however, additional co ntrol measures will be needed to meet the more stringent state PM-10 standard.Mammoth Lakes AQMP10Table 2-1. Summary of PM-10 air quality standard violations for the Town of Mammoth LakesYearMaxPM-10(μg/m3)Number ofFederalExceedances(>150 μg/m3)Number ofStateExceedances(>50 μg/m3)Number ofValidSampleDaysDataCaptureOK?Expected #of FederalExceedances(>150 μg/m3)Expected #of StateExceedances(>50 μg/m3)1990 161 2 14 58 Y 12.6 88.11991 134 0 9 48 N 0 68.41992 138 0 14 60 Y 0 85.21993 178 1 10 59 Y 6.2 61.91994 92 0 10 58 Y 0 62.91995 122 0 6 58 Y 0 37.81996 74 0 4 51 Y 0 28.61997 112 0 6 59 Y 0 37.11998 106 0 3 37 N 0 29.61999* 0 N2000* 70 0 3 18 N 0 60.82001 134 0 4 48 Y 0 30.42002 129 0 4 17 N 0 85.92003 74 0 3 86 N 0 12.72004 86 0 8 109 Y 0 26.82005 85 0 8 92 N 0 31.72006 78 0 7 110 Y 0 23.22007 67 0 5 115 Y 0 15.92008 138 0 17 164 Y 0 37.82009 118 0 26 365 Y 0 262010 104 0 44 348 Y 0 46.12011 128 0 38 360 Y 0 38.52012 56 0 5 342 Y 0 5.3*PM10 monitor site closed for building renovation. AQS data for 1990 - 2001 is 1 in 6 day PM-10 Partisol;2002 - Oct. 24, 2008 is 1 in 3 day PM-10 Partisol; Oct. 24, 2008 - 2012 is both 1 in 3 day Partisol and dailyFDMS TEOM. Source: US EPA Air Quality System (US EPA, 2014)Mammoth Lakes AQMP

11 3. Federal and State Air Quality Standards for Particulate Matter

3.1 FEDERAL PM-10 AND PM-2.5 STANDARDS

On July 1, 1987, EPA revised the NAAQS for particulate matter with a new PM-10 indicator as the basis for the standards ( 52 FR 24634). The level of the federal PM-10 standard was set at 150 μ g/m 3 for a 24-hour average concentration and 50 μ g/m 3 for an annual average concentration. The new PM-10 standard replaced the previous standard for total suspended particulates (TSP less than 30 microns in diameter). The change from the TSP standard to PM-10 was in response to updated information from health officials indicating adverse human health effects from the smaller PM-10 penetrating deep into the lower respiratory tract and lung tissue.

In 1997, EPA retained the existing 24-hour and annual PM-10 standard after reviewing the PM NAAQS. However, EPA expanded the PM NAAQS by adding a new PM-2.5 standard based on updated human health research im pacts from fine-sized particles 2.5 microns or less in diameter. Th e PM-2.5 standard was set at 65 μ g/m 3 for a 24-hour average concentration and 15 μ g/m 3 for an annual average concentration (62 FR 38652).

In 2006, EPA reaffirmed the 24-hour PM-10 standar d after reviewing the air quality criteria and PM NAAQS again. EPA concl uded that the research “evidence continues to support a 24-hour averaging time for a coarse particu late standard, based primarily on evidence suggestive of associations between short-term (24-hour) ex posure and morbidity effects and, to a lesser degree, mortality” (71 FR 61144-64233). However, effective December 18, 2006, EPA revoked the annual average P M-10 standard based on the more recent studies indicating long-term heal th impacts were mainly rela ted to PM-2.5 exposure. EPA also tightened the 24-hour average PM-2.5 standar d by lowering the concentration level from 65 μ g/m 3 to 35 μ g/m 3 (71 FR 61144-64233).

Table 3-1. National Ambient Air Qu ality Standard for Particulates*

Pollutant Primary/ Secondary Averaging Time Level Form

Particle Pollution Dec 14, 2012 PM-2.5 primary Annual 12 μ g/m 3 annual mean, averaged over 3 years

secondary Annual 15 μ g/m 3 annual mean, averaged over 3 years primary and secondary 24-hour 35 μ g/m 3 98th percentile, averaged over 3 years

PM-10 primary and secondary 24-hour 150 μ g/m 3 Not to be exceeded more than once per year on average over 3 years

*U.S. EPA 2013Mammoth Lakes AQMP

12 3.2 CALIFORNIA CLEAN AIR ACT REQUIREMENTS

The California Air Resources Board adopted new state PM standards in June of 2002, responding to requirements of the Children's Environmental Health Protection Act. This Act requires the evaluation of all health-bas ed ambient air quality standards to determine if the standards adequately prot ect human health, particularly that of infants and children. The subsequent review of t he PM standards resulted in the recommendation of more health-protective ambient air quality standards for PM-10 and a new standard for PM-2.5. The new California PM standards became effective in 2003.

Table 3-2. California Ambient Air Quality Sta ndard for Particulates* Pollutant Annual Average 24-Hour Average PM-10 20 μ g/m 3 50 μ g/m 3 PM-2.5 12 μ g/m 3
- *California Air Resources Board, 2013

3.3 MAMMOTH LAKES PM COMPLIANCE

As discussed in the following section, air monitoring data for Mammoth Lakes shows that the area has been in compliance with the feder al PM-10 standard since 1993, when the number of standard exceedances was less than 1.0 per year averaged over three years This compliance status has been maintained c ontinuously since 1993. However, the area continues to violate the more st ringent State PM- 10 standard.

The Town of Mammoth Lakes is designated as attainment/unclassifi ed for the federal PM2.5 standard and attainment for the state PM-2.5 standard. These designations also apply to the larger Great Basin Valleys Air Ba sin, which includes all of Mono, Inyo and Alpine Counties in California. (CARB, 2013)Mammoth Lakes AQMP

13 4. Air Quality Data

The air quality data section covers the ambient particulate matter monitoring and meteorological data. This information is inco rporated into the air quality modeling and control strategy analysis along with emissi ons inventory data that is covered in subsequent chapters of this Plan.

4.1 PM-10 AND METEOROLOGICAL MONITORING SITE

Airborne pollutant and meteor ological monitoring are condu cted at the Gateway (also known as the Rite Aid/Do-It Yourself) shopping center in Mammoth Lakes. Four types of PM-10 monitors have been used at the monitoring site; a Size Selective Inlet (SSI) and a dichotomous sampler (dichot), which both m easure once every six days, PM-10 Partisol, which measures once every 3 days, and a TEOM (Tapered Element Oscillating Microbalance) which provides daily and hour ly PM-10 concentrations. The TEOM was often operated with a co-located PM-10 Partisol. Although eac h monitor is a U.S. EPA approved reference or equivalent method samp ler, PM-10 concentration measurements can vary. Due to the 50oC in let temperature of the TEOM, particulate matter from wood smoke can volatize and cause the mass measurem ent to be low as compared to the other PM-10 monitors. TEOM values during peri ods of heavy wood smoke can be estimated by multiplying the TEOM measur ed value by 1.8. In 2006, th e TEOM was modified to an FDMS (Filter Dynamics Meas urement System) TEOM. T he FDMS TEOM can account for particulate matter volatilization and pr ovide the correct mass. However, due to operational problems with the FD MS it was replaced with a regular TEOM in 2007. A new FDMS TEOM was installed in November 2008. PM-10 monitor data is not available for 1999 and 2000 because the building that housed the monitor was being renovated. The type of PM-10 monitor used in each year is identified in Table 2-1.

4.2 PM-10 AND DATA SUMMARY

Table 2-1 shows that the Mammoth Lakes Planning Area has not exceeded the federal 24-hour NAAQS since 1994. From 1990 through 1994, five exceedences were recorded. Because of the sampling interval, this equates to an expected total of 21 exceedences with 19 occurring in 1990, prior to the adopt ion and implementation of the 1990 AQMP. Since 1990, only two exceedances of the 24-hour NAAQS were recorded – one in 1991 and one in 1994.

Although the federal standard for PM-10 is currently bei ng met, the more stringent California Ambient Air Quality Standard for P M-10 is still violated in Mammoth Lakes. The state 24-hour average PM-10 standard is set at 50 μg/m 3 . As seen in Table 2-1, the number of monitored st ate standard violations was as high as 88 days in 1990, the year the AQMP was adopted. Violatio ns of the state standard have declined since then. Over the last three years (2010-12), the average number of state PM-10 violations was around 30 per year.Mammoth Lakes AQMP

14 4.3 PRE AQMP PM-10 VIOLATIONS

Prior to the adoption of the 1990 AQ MP, violations of the 150 μg/m 3 24-hour National Ambient Air Quality Standard (NAAQS) for PM-10 were measured on seven occasions the Gateway Center monitoring site. Beca use the samples were being measured on a one every six day cycle, the actual number of violations was estimated to be higher. These violations occurred during the win ter season 1985-86 through 1988-89. The highest measured PM-10 c oncentration was 210 μg/m 3 . Since 1995, there have been no violations of the 24-hour NAAQS and the highest recorded value was 136 μg/m 3

. Monitoring since 1991 has been daily.

The measured exceedances evaluated in the 1990 AQMP occurred during periods of low average wind speed, less than 3. 5 mph. Violations primarily occurred on weekends (Friday, Saturday, or Sunday) or during t he holiday period around Christmas and New Year’s. Data analyzed for this Pl an follow that same trend.

4.4 PARTICULATE MATTER TREND

The particulate matter trend has generally shown air quality improvement since the adoption of the 1990 AQMP. Figure 4-1 show s that the trend of quarterly average PM10 concentrations decreased following the adopti on of the AQMP with a leveling over the last 10 years. Figure 4-2, shows that for the winter months (November-March) the average winter and peak winter concentrations were generally downward after control measures were implemented, but have st arted to increase since 2008.

4.5 PM-2.5 Data

PM-2.5 monitoring at the Gateway Center shows that since 2000 , Mammoth Lakes has met the 24-hour and Annual NA AQS for PM-2.5 (35 and 12 μ g/m 3 , respectively). The 98 th percentile and annual average PM-2.5 levels are shown in Table 4-1.

Table 4-1 PM-2.5 Monitoring Results 98 th Percentile Concentration ( μ g/m 3 ) Annual Average

2000 30.8 N/A 2001 36.2 N/A 2002 N/A N/A 2003 30.5 7.48 2004 24.7 N/A 2005 26.9 N/AMammoth Lakes AQMP15020406080100120140160180J-90 J-91 J-92 J-93 J-94 J-95 J-96 J-97 J-98 J-99 J-00 J-01 J-02 J-03 J-04 J-05 J-06 J-07 J-08 J-09 J-10 J-11 J-12 J-13

PM-10 (micrograms per cubic meter)YearFigure 4-1, Mammoth Lakes PM-10Quarterly Peaks & Averages (1990-2013)Quarterly PM-10 AverageHighest Daily PM-10 During QuarterQuarterly PM-10 TrendHighest Daily PM-10 TrendMammoth Lakes AQMP16020406080100120140160180

PM ‐ 10 (μg/m3)Figure4‐2,MammothLakesPM‐10WinterSeasonPeaks&Averages(1990‐2013)MaxDailyPM‐10(November‐March)AveragePM‐10(November‐March)WinterSeasonMaxDailyPM‐10TrendWinterSeasonAveragePM‐10TrendMammoth Lakes AQMP

17 5. Emissions Inventory

The emissions inventory section covers th e PM-10 emission estimates for residential wood combustion (RWC), resuspended road dust and cinders, mobile source tailpipe emissions and point sources. The methodology and data used to determine emissions is discussed for each source type. Because Mammoth Lakes exceeds the state 24-hour PM-10 standard, the emissions inventory is estimated for a peak 24-hour period. These emission estimates consider the large influx of visitors to Mammoth Lakes during the winter ski season.

Road dust and vehicle emissions are provided s eparately for traffic wit hin the boundaries of the Town of Mammoth Lakes and for highwa ys 203 and US 395 that are located outside of the Town boundaries. Although vehicle- related emissions from roadways located outside the town are gener ated within the nonattainm ent area boundary, PM-10 emissions from areas east of t he Town do not contribute to t he air quality problem in the Town. An analysis of wind speeds and dire ctions on the high PM-10 days used for the receptor modeling analysis in Ch apter 6 shows that 98% of t he hourly winds were low (< 2 m/s) and primarily from the west, which w ould push emissions from areas east of the Town away from the monitor location that was used for the receptor modeling analysis. Therefore, PM-10 emissions from areas outside of the Town boundaries are not considered relevant to the maintenance demonstration in C hapter 8 and were separated from the in-town emission estimates. The areas outside of the Town boundaries are also largely uninhabited pub lic lands, therefore t here is an absence of residences that would contribute wood smoke emissions to the emi ssions inventory. T he in-town emissions inventory is considered to be the appropriate inventory for sour ces that are most likely to contribute to high PM-10 concent rations at the monitor site.

The peak daily emissions inventory for th e Mammoth Lakes Planning Area does not include emissions from unpaved road dust or construction activities. Emissions from these sources are seasonal and are abs ent during the winter when high PM10 concentrations occur. Unpaved roads are either snow covered or muddy during the winter season and outdoor building and roadway construction activities generally do not take place until around May when the weather warms. 5.1 WOODSTOVES AND FIREPLACES

Emission rates for woodstoves and fireplaces are based on the type of wood burner, the type of wood burned, and the usage rate. The usage rate was based on the different burning habits of 1) condomin ium residents, 2) residents in single-family homes and 3) residents in apartments and mobile homes. Estimates for the annual and 24-hour PM-10 emissions are calculated for wood burning. The annual emissions estimates, which are based on survey data, provide good information to improve the estimates for the peak 24- hour period.

5.2 NUMBER OF WOODSTOVES AND FIREPLACES

The numbers of woodstoves and fireplaces ar e based on the numbers of condominiums, single-family homes, apartm ents and mobile homes, and t he estimated number ofMammoth Lakes AQMP

18 woodstoves and fireplaces in each type of housing. Table 5-1 shows the estimated number of wood burning units fr om surveys for each housing type in the Planning Area.

Table 5-1, Residential Wood Burning Device Count

Condominium Single Family Mobile home/ apartment Total

Fireplaces 264 29 0 293 Woodstoves (EPA) 3,289 1,290 193 4,772 Pellet Stoves 297 87 16 400 Woodstoves (uncert) 116 106 9 231

3,966 1,512 2,18 5,696
Town of Mammoth Lakes 2013

A partial survey being conducted by the Mammoth Lakes Fire Protection District indicates a higher number of unregulated firepl aces (437 versus 293). The AQMP uses the lower number to maintain a conservative estimate of control measure effectiveness. Replacement of a larger number of fireplaces would create a greater reduction in PM-10 than forecast by this AQMP.

5.3 WOODSTOVE AND FIREPLACE USAGE

The estimate of the amount of wood burned is based on a survey conducted during the winter of 2012 – 2013. The survey was se nt to over 6,000 pr operty owners and 4,500 Post Office Box holders in Mammoth Lakes. 574 of the surveys we re returned. Table 5.2 summarizes the average amount of wood bur ned during the winter heating season in homes that have a wood burning device.

Table 5-2, Amount of Wood Burned Annually in Homes With Wood Combustion Devices* Condominium Single-Family Mobile Home & Apartment Wood Burning Pellet Wood Burning Pellet Wood Burning Pellet

1.4 cords 2000 lbs 2.4 cords 2400 lbs 2.3 cords 3000 lbs

* Town of Mammoth Lakes 2013

5.4 ANNUAL PM-10 EMISSIONS ESTIMATE FOR RWC DEVICES

The emission estimates for RWC devices ar e based on the Environmental Protection Agency’s emission factors (US EPA AP 42). T hese emission factors are based on in situ tests of wood burning devices. Emission factors are given as grams of PM-10 per kilogramMammoth Lakes AQMP

19 of dry wood burned. The emission factors are shown in Table 5-3. This table also summarizes the total emissions for each RW C device and housing type. Emissions for each RWC device are calculated using the follo wing equation:

PM-10 emissions/device = mass wood x EF where:

EF = 16.3 g/kg for uncertified woodstoves and fireplaces 7.3 g/kg for EPA certified woodstoves 2.1 g/kg for pellet stoves

The cord density (800 kg per cord) is assumed for ponderosa pine which has a weight density of 10 kg/ft.3 A cord is approximatel y 80 ft.3 wood per cord (Davis and Read, 1989). Based on available data this is the best appr oximation for the Jeffrey and Lodgepole pine that is primarily burned in Mammoth Lakes. The total number of fireplaces and wood stoves is taken from Table 5-1, but this ca tegory is further broken down into uncertified, and EPA-certified based upon the Town of Mammo th Lakes building permit records for change outs and new construction.

The annual emission estimate for PM-10 of 58,663 kg provides a good basis for comparison with a peak 24-hour emission estima te. The 24-hour emission estimate is critical since woodburning is a significa nt contributor to 24-hour PM-10 standard exceedances.

5.5 24-HOUR PM-10 EMISSIONS ESTIMATE FOR RWC DEVICES

To estimate the peak 24-hour emissions invent ory for wood burning, it is assumed that all RWC devices are operating and burn an average of 2.4 ft.3 (or 24 kg) of wood per day. The amount of wood burned is based on the in formation provided through the Town’s 2013 wood burning survey. Table 5-4 shows a summary of the esti mates for the PM-10 emissions from each type of wood burning device and from diff erent housing types. With

Table 5-3 Annual PM-10 Emission Esti mates for Residential Wood Combustion

Condominiums Single Family Mobile Homes and Apartments

RWC Device Emission Factor Wood/ Pellets Units PM-10 kg Wood/ Pellets Units PM-10 kg Wood/ Pellets Units PM-10 kg Emissions Total (kg)

Fireplace/ uncertified stove 1 16.3 1.17 cords 380 5,798 2.4 cords 135 4,225 2.3 cords 9 270 10,292

Woodstove (EPA) 7.3 1.4 cords 3,289 26,891 2.4 cords 1,290 18,081 2.3 cords 193 2,592 47,564 Pellet 2.1 900 kg 297 561 1,090 kg 87 199 1,360 kg 16 46 806

33,250 22,505 2,908 58,663Mammoth Lakes AQMP

20 these assumptions, it is estimated that RW C devices contribute appr oximately 850 kg of PM-10 during a peak wood-burning day.

Table 5-4 Peak 24-Hour Emission Estimates for Residential Wood Combustion

Condominiums Single Family Mobile Homes and Apartments

RWC Device Emission Factor g/kg Fuel kg/day Units PM-10 kg/day Fuel kg/day Units PM-10 kg/day Fuel kg/day Units PM-10 kg Emissions Total (kg)

Fireplace/ uncertified stove 16.3 19 380 118 27 135 59 19 9 3 180

Woodstove (EPA) 7.3 19 3,289 456 19 1,290 179 19 193 27 662

Pellet 2.1 9 297 6 11 87 2 14 16 0 8

579 240 30 850

5.6 24-HOUR PM-10 EMISSIONS ES TIMATE FOR ROAD CINDERS

The PM-10 emission estimate for resu spended road cinders is based on the AP-42 methodology for estimating reentrained road dust emissions from paved roads (US EPA, Compilation of Air Pollution Emissions Fact ors, AP-42, 1995, updated) . The formula for the emissions factor is:

E = k(sL) 0.91 x (W) 1.02 where:

E = Emissions Factor k = Particle size multiplier sL = Road surface silt loading (g/m 2 ) W = Average weight (tons) of t he vehicles traveling the road

The silt loading factor is tak en from the calculations in the 1990 SIP and is estimated to be 8.7 g/m 2 , Statewide average vehicle weight is 2. 4 tons (CARB, 1997), and the particle size multiplier from AP-42 is 1. (US EPA AP- 42) This produces an emissions factor of 17.49 grams of PM-10 per VMT. When multiplied by VMT pe r day, the result is the estimated mass of PM-10 per day from ro ad dust (Table 5-5). Total peak day PM-10 emissions from road dust is estimated at 2,522 kg/day based on peak traffic volume in 2009 within the boundaries of the Town of Mammoth Lakes (see Figure 1.2).

A separate PM10 emissions estimate is prov ided for road dust generated from traffic on US Highway 395 and the portion of Highway 203 that is outside the Town of Mammoth Lakes boundary. Although emissions in th is area are generated within the larger nonattainment area boundary, the em issions from the areas to the east of the Town do not contribute to the air quality problem in th e Town. An analysis of the wind speeds andMammoth Lakes AQMP

21 directions on the high PM10 days used for t he receptor modeling analysis shows that 98% of the hourly winds were lo w (< 2 m/s) and prim arily from the wes t, which would push emissions from these areas aw ay from the Town. The plann ing area emissions inventory for road dust emissions were based on t he winter 2008-09 vehicle traffic data for Highways 395 and 203 (Caltrans, 2014). This yiel ded an average of 53 ,319 vehicle miles travelled per day. Since road cinders are applied to Highways 203 and 395 in the winter the same emission factor used in the Town wa s applied. This yielded an estimate of 933 kg/day for road dust emissions fr om areas outside of the Town.

An annual emissions estimate for road dust was not calculated since it is not needed to evaluate compliance with t he 24-hour PM-10 standard.

*LSC, 2012a for In-town, and Ca ltrans, 2014 for Out-of-town

5.7 VEHICLE TAILPIPE, TIRE AND BRAKE WEAR EMISSIONS

PM-10 emissions from motor vehicle exhaust, tire and brake wear were determined by the California Air Resources Board using EM FAC2011 (CARB, 2014) . As discussed for road dust emissions, these emissions were es timated for vehicles operating within the Town of Mammoth Lakes boundary and those t hat were on Highways 203 and 395 in the portion of the nonattainment area t hat is outside of the town. Ta ilpipe, tire and brake wear were calculated to be 0.060 g/ VMT in the Town and 0.046 g/VM T outside of the Town. Different emission factors were generated by EMFAC2011 to account for the vehicle speed ranges in-town (0-45 mph) as compared to the higher out-of-town vehicle speeds on highways 203 and US 395 (0-65 mph). Using the daily peak traffic volume of 144,192 vehicle miles travelled for roadways in the Town and 53,319 for the highways 203 and 395 for the remainder of the pl anning area, the vehicle emissions estimate is 9 kg/day in town and 2 kg/day out of town.

An annual emissions estimate for tailpipe emi ssions was not calculated since it is not needed to evaluate compliance with the 24-hour P M-10 standard, Table 5-5. 24-Hour Road Dust Emissions

Area Particle Size Multiplier Silt Loading Average Vehicle Weight Emissions Factor g/VMT 2009 VMT* Total 24-Hr PM-10 (kg)

In-town 1 8.7 2.4 17.49 144,192 2,522 Out-of-town 1 8.7 2.4 17.49 53,319 933Mammoth Lakes AQMP

22 5.8 INDUSTRIAL POINT SOURCES

The Great Basin Unified Air Pollution Control District permits industrial sources within the Town of Mammoth Lakes. Those sources pr oduce a total of 8 kg/day during the winter (Table 5-6).

Table 5-6 Permitted Particulate Matter Sources Within the Mammoth Lakes AQMP
Facility: equipment

*Indicates facilities located in Town PM-2.5 PM-10 Peak Winter

Day (kg/day) Annual (kg/yr) Peak Winter

Day (kg/day) Annual (kg/yr)

7/11 Materials: concrete batch plant NA 1,998 NA 4,147 CA Dept. Fish & Game - Hot Creek: 1 backup engine 0.04 1.6 0.04 1.6 Mammoth Hospital: 7 boilers, 1 fire & 2 backup engines 3.18 1,130 3.18 1,130
Mammoth Mountain*: 4 boilers, 19 backup engines 4.18 130 4.18 130 Mammoth Pacific: 2 engines 0.05 2.4 0.05 2.4 Marzano & Sons: concrete batch plant NA 1,801 NA 3,740 Monache Condominium*: 1 backup engine 0.05 2.6 0.05 2.6 Verizon (Mammoth H.S.)*: 1 backup engine 0.036 1.9 0.036 1.9 Verizon California - Mammoth Lakes*: 1 backup engine 0.03 1.4 0.03 1.4

Nonattainment Area Total 8 5,069 8 9,157

In-Town Total 4 136 4 136 GBUAPCD, 2014

5.9 SUMMARY OF PM-10 EMISSIONS

Woodburning and resuspended road cinders compri se almost all the PM-10 emissions during the winter. Motor vehicle exhaust, ti re and brake wear, and industrial sources contribute approximately 1.4% of the area wide inventory. The current total PM-10 emissions on a peak winter day in the To wn of Mammoth Lakes and the larger nonattainment area are summarized in Table 5-7.

Table 5-7. Summary of Peak 24 hour PM-10 Emissions (kg/day) 2012

Source In Town of Mammoth Lakes Nonattainment Area Total Residential Wood Combustion 850 850 Road Dust/Cinders 2,522 3,455 Tailpipe, Tire & Brake Wear 9 11 Industrial Sources 4 8 Total 3,385 4,324Mammoth Lakes AQMP

23 6. Receptor Modeling

Receptor modeling is based on the idea that the total mass of the receptor (ambient sample) is a sum of the contributions from in dividual sources. Each source has a unique “fingerprint” of various proportions of chem ical elements which comprise it. This fingerprint is expressed in fractions of t he total (e.g., 20% potassium, 30% silica, 40% carbon, etc.). Knowing the composition of the ambient sample, and the compositions of the possible sources, one can estimate (using least-squares estimation) the fraction of each source contribution to the total ambien t mass. This type of data manipulation is called receptor modeling because it bases its analysis of an air pollution scenario on information gathered at the receptor.

Another air pollution modeling me thod is dispersion modeling, which starts with precise information about source characteristics, terr ain and meteorology to predict the pollutant concentrations at downwind receptor locati ons. Dispersion models are especially useful in predicting the effects of point source em issions, such as from industrial smokestacks. But their predictive accuracy is strained under low wind speed conditions and situations dominated by emissions from numerous sma ll point sources, such as resuspended road dust and residential wood combustion, the precis e conditions that characterize the air pollution problem in Mammoth Lakes.

The receptor model does not directly consider the wind speed or source characteristics, other than chemical com position to determine the ambient im pact of sources. So receptor modeling is particularly useful for performing t he air quality analysis for the conditions that exist in Mammoth Lakes.

6.1 AMBIENT PROFILES

The Desert Research Institute of Reno, Nevada (DRI) conducted a chemical mass balance (CMB) study for Mammoth Lakes in 2013. DRI analyzed twelve PM-10 and four PM-2.5 filters (dates and c oncentrations shown in Tables 6-1 and 6-2) for elements and ions. The twelve PM-10 filters included t he nine highest and 11th highest PM-10 filter concentration days since 2001, ei ght of which were since t he start of 2008. The other four PM-10 filters are days for which high PM-10 and/or PM-2.5 concentrations were measured and both PM-10 and PM-2.5 filters are available for each day. Three of these four days had the highest PM-10 for days with P M-2.5 filters also. The other day had high PM-2.5 and high PM-2.5 to PM-10 ratios (indicative of large relative wood smoke impact). Because road dust is expected to be mostly in the larger particle sizes and wood smoke mostly in the smaller sizes (PM-2.5) analyzing both PM-10 and PM-2.5 for a few days provided supporting evidence for the estimates based on the PM -10 data. The full report is included as Appendix G.

The chemical analysis included X-ray fluoresc ence (XRF), which quantified most of the chemical elements, ion chromatography for ani ons and cations, and li ght absorption. The XRF analysis provided the contributions from road dust elements, ion chromatographyMammoth Lakes AQMP

24 the contributions from sulfate and nitr ate, and ammonium. The light absorption measurement is a good indicato r of elemental carbon (EC) (diesel exhaust and wood smoke primarily). What the anal ysis could not identify that is important is organic carbon (OC), because the carbon-based Teflon filters interfere with measurements of carbon associated with the collected par ticulates. Because of this, organic carbon was estimated from the residual mass in the CMB analysis.

Table 6-1. Dates with only PM-10 filters: Date PM-10 concentration 1/1/2008 85.9 2/9/2008 96.7 2/27/2008 95.5 2/21/2009 117.6 1/2/2010 101.3 1/29/2010 104.0 2/13/2010 92.0 1/12/2011 127.6

Table 6-2. Dates with P M-10 and PM-2.5 filters: Date PM-10 PM-2.5 12/17/2003 74.6 33.5 1/13/2005 39.3 27.0 1/19/2005 85.1 25.2 1/22/2005 77.8 27.4

6.2 SOURCE PROFILES

6.2.1 PM-10 analysis

The chemical source profile s, or fingerprints, were ta ken from the 1990 AQMP. The sources profiled were:

 Mammoth Lakes road cinder storage

 Mammoth Lakes paved road dust

 idling diesel ski tour buses in Mammoth Lakes

 fireplace burning a typical Mammoth Lakes wood mix

 a Fisher woodstove with ty pical Mammoth Lakes wood mix

Profiles for Mammoth Lakes woodstoves and fireplaces were used plus road dust and cinders. When running CMB it was found that due to their similar chemical fingerprints, significant collinearity occurred between the wood stove and fireplace sources, giving high uncertainty to wood stove contributions (sometimes significantly negative). CMBMammoth Lakes AQMP

25 was run again not using the wood stove source , just fireplaces, cinders, and road dust. This gave better results. It wa s attempted to improve results by averaging the wood stove and fireplace profiles, but the qua lity of the results deteriorat ed. A weighted average of three parts fireplace to one part wood stove prof ile was also tried and results were not as good as simply using the fireplace profile.

6.2.2 PM-2.5 analysis

The PM-2.5 analysis had collinearity problem s between woodstove and fireplace and between road dust and cinders. The analysis with the best results used fireplaces and road dust source profiles only.

6.2.3 Fitting species

CMB results can vary significantly based on the choice of fitting species selected. In the initial run, all specie s measured with available source anal ysis were used. This gave poor results. Species that were noted from the ambient data to represent the mix of sources were added and subtracted in a trial and error met hod until the best results were obtained. Attention was paid to squared correlation coef ficient, the Chi square statistic and percent of mass explained performance measures (Wat son, 2004). The fitting species included: soluble Cl, ammonium, soluble K, total K, Na , Al, Si, S, Ca, Ti, Fe, EC, OC, Ba, Sr, and Zn.

6.3 CHEMICAL MASS BALANCE RESULTS

CMB model version 8 (USEPA) was used to esti mate source contributions to PM-10 and PM-2.5 for days with chemically speciat ed data. CMB analysis done in support of the 1990 Air Quality Management Plan (AQMP, Ono et al, 1990) for Mammoth Lakes showed most of the PM-10 was due to road dust and residential wood combustion (RWC). One of the goals of the 2013 study wa s to try to determine if the relative contribution of RWC and road dust has changed sinc e the1990 report (DRI, 2013).

Results for the best fitting CMB analysis ar e shown in Table 6-3. Recommended performance measures (Watson, 2004) are % mass accounted for 100±20%, Rsquared>0.80, and Chi-squared < 4. 0. For the PM-10 results (discounting the 1/12/2010 sample), 10/11 cases have % mass 100±20%, all cases have R-squared>0.80, and 5/11 meet the Chi-squared <4.0 criteria. For the PM-2.5 results, three out of four met the mass criteria and all four met the R- squared and chi-squared criteria.

The percent of each sample attributed to each s ource is shown in Tabl e 6-4. On average, residential wood combustion cont ributed about 64% of the PM- 10, road dust plus cinders contributed about 33%, according to the CMB results (DRI, 2013).Mammoth Lakes AQMP

26 DRI, 2013

Table 6-4. CMB Percent Contributions by Road Dust (RD), and Residential Wood Combustion (RWC) 1987-88 and 2003-2011 Data Sets 1990 AQMP PM-10 Source Percentages 2013 AQMP PM-10 Source Percentages Date Conc. RD% RWC% Date Conc. RD% RWC% 12/26/1987 125.9 2.3 97.7 12/ 17/2003 74.6 25.3 74.7 12/30/1987 132.8 1.3 98.7 1/ 19/2005 85.1 33.7 66.3 12/31/1987 142.8 2.5 97.5 1/ 22/2005 77.8 32.5 67.5 1/1/1988 117.4 10.3 89.7 1/ 1/2008 85.9 39.5 60.5 1/22/1988 143.8 33.7 66.3 2/9/2008 96.7 24.3 75.7 1/23/1988 157.8 41.2 58.8 2/ 27/2008 95.5 39.4 60.6 2/3/1988 104.3 31.5 68.5 2/21/2009 117.6 32 68 2/5/1988 148.2 33.8 66.2 1/ 2/2010 101.3 27.7 72.3 2/6/1988 160 31.2 68.8 1/29/2010 104 36 64 2/13/1988 137.6 38.8 61.2 2/13/2010 92 33.8 66.2 2/14/1988 144 45.2 54.8 2/19/1988 148.5 28.7 71.3 1987-88 study average 25 75 This study average 32.4 67.6 DRI, 2013 Table 6-3. CMB attr ibution results and pe rformance statistics.
DATE SIZE Conc. FP RD CIND SUM % mass R 2 Chi 2 12/17/03 10 74.6 53.0 9.6 10.2 72.8 97.5 0.94 3.70 01/13/05 10 39.3 31.1 3.6 1.7 36.5 92.7 0.92 3.76 01/19/05 10 85.1 51.8 18.1 11.5 81.3 95.5 0.93 4.39 01/22/05 10 77.8 47.5 16.9 8 .7 73.0 93.8 0.94 3.70 01/01/08 10 85.9 53.4 24.6 14.8 92.9 108.1 0.93 4.73 02/09/08 10 96.7 68.0 10.2 13.8 92.0 95.1 0.94 3.35 02/27/08 10 95.5 52.6 26.1 12.7 91.3 95.6 0.90 6.40 02/21/09 10 117.6 91.7 26.6 21.0 139.3 118.5 0.94 3.89 01/02/10 10 101.3 100.4 23.2 19.0 142.6 140.8 0.90 6.88 01/29/10 10 104.0 65.8 24.5 16.8 107.1 103.0 0.93 4.52 02/13/10 10 92.0 68.9 25.9 13.9 108.7 118.2 0.91 6.09 01/12/11 10 127.6 43.9 2.2 1.8 47.9 37.5 0.82 8.77 12/17/03 2.5 40.6 28.6 1. 5 30.0 74.0 0.96 0.90 01/13/05 2.5 32.7 27.5 0. 6 28.1 86.0 0.81 3.90 01/19/05 2.5 30.5 28.1 2. 2 30.3 99.3 0.89 2.73 01/22/05 2.5 33.2 27.6 1. 9 29.5 89.0 0.92 2.00Mammoth Lakes AQMP

27 For the winter 1987-1988 study (Ono et al, 1990) , on average, fireplaces contributed 75% of the PM-10 and road dust 25%. Table 6-4 com pares the results of the 1987-88 study to this study. Three of the days in the 1987-88 study showed wood smoke contributing >95% of the PM-10; the current study s hows no high PM-10 days with greater than 75% of the PM-10 contributed from wood smoke (DRI, 2013).

Furthermore, the peak contributions of r oad dust and residential wood combustion to PM10 appear to have diminished. A comparison of the results from the 1987-88 study to the 2008-2010 study period showed t hat the average PM-10 contri butions for the top three days in each study dropped from 107 to 72 μg/m 3 for wood smoke and from 72 to 56 μg/m 3 for road dust. This represents about a 33% reduction in the ambient PM-10 concentrations for both source categories that can be attributed to the implementation of the 1990 AQMP. (DRI, 2013).

6.4 CHEMICAL MASS BALANCE SUMMARY AND CONCLUSIONS

The question of the relative contributions of wood smoke and road dust to PM-10 in Mammoth Lakes was considered. Teflon filters from hi gh PM-10 days between 2003 and 2011 were subjected to chemical analysis with XRF, ion chromatography, and filter light absorption. Four days analyzed also had PM-2.5 filters that underwent chemical analysis. A major limitation was the inability to measure carbon on the f ilters. The filter light absorption provided a r easonable estimate of elemental carbon and the unexplained mass (on average 58% of PM-10 and 68% of PM-2.5) was assumed to be organic mass (OC*1.8). Estimates of the contribution of wood smoke and road dust were made using Chemical mass balance and a simple met hod based on abundance of crustal elements in the samples. For PM-10, CMB showed an average of 32% due to road dust and 68% due to residential wood combustion. This co mpares to 25% from road dust and 75% from residential wood combustion for the win ter 1987-88 study. The CMB maximum contributions (average of th ree highest days) to PM-10 from road dust and residential wood combustion dropped by about 33% for eac h source category between 1987-1988 and 2008-2010 (DRI, 2013).Mammoth Lakes AQMP

28 7. Control Measures

In December of 1990, the Town of Mammo th Lakes adopted the Air Quality Management Plan (AQMP) for the Town of Mammoth Lake s. The AQMP relied on controlling wood smoke by replacing old wood stoves and firepl aces with cleaner wood burning appliances and curtailing wood burning on days that could violate the air quality standard. The Town reduced road dust emissions by using vacuum street sweepers to remove volcanic cinders soon after the roads dried. The 1990 control measures are described in Section 2 and are summarized below. An assessm ent of their effectiveness follows:

7.1 PARTICULATE EMISSIONS REGULATIONS

As a part of the implementation program, t he Town of Mammoth Lakes adopted Municipal Code Chapter 8.30, Particulate Emissions Regu lations. Major controls in the Chapter 8.30 regulations were:

 Replacement or removal of existing uncertified residential wood combustion appliances at the time of sale of a property;

 Limit the maximum number of residentia l wood combustion appliances in new construction to one certified applianc e plus one pellet fueled appliance;

 Institute voluntary and mandator y wood burning curtailment days;

 Implement a public ed ucation Program;

 Implement a vacuum st reet sweeping program; and

 Limit peak VMTs to 106,600.

7.2 CONTROL MEASURES OVER VIEW AND EFFECTIVENESS

7.2.1 Wood Stove & Fireplace Change-outs

In 1990, there were 5,946 woodstoves and fir eplaces with less than 1% of those being EPA-certified. In 2013, the num ber of wood burning appliances is estimated at 5,696 with approximately 91% of the appliances being EPA certified woodstoves (Town of Mammoth Lakes, 2013)).

Although the number of wood burning appliances decreased by roughly 4% from 1990 to 2013, wood smoke emissions went down by about 50% as a result of replacing old wood stoves and fireplaces with EPA-certified w ood stoves, pellet stoves and gas fueled appliances. This reduced wood burning PM-10 emissions on permissive burn days from 2,087 kg/day to 850 kg/day during this same time period.

There are indicators that wood heating has decreased since the adoption of the regulations in the AQMP. Town of Mammoth records through June of 2013 show that of the total of 5,414 change outs between Decem ber of 1990 and March of 2013, 577 were replaced with propane fueled appli ances. It is expected that this trend will continue as older residences are torn down and replaced or renovated. Many of the older buildings in town have poor insulation and rely on electric heat as their primary heat source.Mammoth Lakes AQMP

29 Occupants of these older residences tend to use more wood as a cost-effective alternative to electricity or propane and the am ount of wood needed is higher. As these properties are upgraded, thei r residential wood combustion use should decline.

Anecdotally, there appeared to be an initial dec line in personal fuelwood gathering based on data maintained by the Mammoth Ranger District. (Kusumoto 2007 and 2013) Those records showed a decline of approximately 30% in the volume of wood collected from 1999 through 2007. However, since that ti me, personal fuelwo od gathering has increased. The increase follows the spike in fuel prices in 2007 and the recession beginning in 2008. It also appears to coin cide with the slight rebound in peak winter PM10 levels shown in Figure 4-2.

Since 1990, most new c ondominiums were approved for construction without woodstoves. Since the adopti on of the 2007 General Plan, the Town has prohibited wood burning appliances in new multi-unit devel opments (Town of Mammoth Lakes, 2007). This prohibition is incorpor ated in the updated Chapter 8. 30 of the Mammoth Lakes Municipal Code.

To enforce the change out requi rements, the Town of Mammo th Lakes worked with local real estate agents to assure that the seller re quirements were disclosed. It also instituted a program that permitted purchas ers to assume responsibility for completing the change out provided that the assumption was in writing and filed with th e Town. The Town obtained copies of all recorded real estate transactions from the County Recorder and cross-checked those transactions with buildi ng permit records to a ssure that property sales and transfers complied with the Particulat e Emissions Regulations. As a result of staffing reductions in the Town, these follow- up programs lapsed in the last five to ten years. The GBUAPCD and the Town have agreed to conduct an inventory of real estate sales for comparison with change out record s and to pursue compliance for noncompliant properties.

Although the rule adopted in 1990 limited the installation of so lid fuel burning appliances to EPA-certified Phase II woodstoves, EPA has recently created another certification program for EPA Phase II qualified fireplaces and fireplace retrofit devices. Due the Phase II test requirements, fireplaces were not allowed to be test ed under the original EPA certification program. They can now be tested under th is new program and if the fireplaces or fireplace retrofit devices are listed by the US EPA as Phase II qualified, they will be allowed to be installed in the Town of Mammoth Lakes. This change is codified in the Town of Mammoth Lakes regulations with the adoption of this AQMP (http://www.epa.gov/burnwise/fire placelist.html#retrofits).

7.2.2 Public Awareness Program.

As described in Section 2, the Town implemented a public awareness program beginning in 1990. All components of the program except for the rental unit tent cards continue to be fully implemented. The t ent card program has not been maintained in recent years and the Town is now investigating havi ng additional cards printed for visitorMammoth Lakes AQMP

30 accommodations. Restoring the tent card program will aid in getting no-burn day compliance (see below).

7.2.3 No-burn Days.

No-burn days are called when a meteorological inversion and calm wind conditions could persist for a given day. The calm air prev ents the dilution and trans port of air pollutants and allows PM-10 concentrations to build up from about 4:00 PM to midnight and then again from 6:00 to 10:00 AM. W hen calm weather is predicted, the Town's meteorologist may call a mandatory or a voluntary no-burn day based on the strength of the forecasted inversion and the Town's population. The meteor ologist indicates if it is a red, yellow or green burn day to let the public know if it is mandat ory, voluntary or if it is okay to burn.

At the beginning of the pr ogram, 10 to 14 mandatory no- burn days were called each winter. Over the past six winters, t he Town has averaged one mandatory and one voluntary no-burn day per winter (Daugherty, 2013). A survey of a residential neighborhood and a condomin ium complex, which was primarily occupied by visitors, showed that full-time residents did not comply with the no-burn day ca lls, while visitors were more responsive, but not fully compliant (Satterfield, 1994a). The survey showed a negative 36% compliance rate for resident s (more wood burned on no burn days) and a positive 35% compliance rate for visitors. The negative compliance rate for the residents was due to having more residents burn on the no-burn survey days than were burning on the survey days when burning wa s allowed. Since the resident population in the survey was small, the negative value is likely within t he statistical uncertainty of the survey and the compliance rate for full-time residents should be considered around zero. Because visitors make up 80% of the population, t hey had a significant influence on the overall town average. The combined town averag e with visitors and residents is about 21% compliance on no-burn days (Satterfield, 1994a). This is short of the expected 50% compliance rate that was expected in the plan. There have been no compliance checks for no-burn days since the 1994 study. The effe ct of the no-burn day compliance shortfall on air quality trends is evaluated in the Maintenance Demonstration section of this report.

In December 2006, a signifi cant change was made to GBUAPCD Rule 431 to make all wood burning appliances, except pellet stoves, subject to no-burn day requirements. Previous to the rule change, only non-EPA certified wood burning appliances were prohibited from being used on no -burn days. EPA certified wood stoves were exempted from the no-burn days and c ould still be operated. Since 85% to 90% of the non-EPA certified wood burning applianc es had been replaced since the adoption of the AQMP in 1990, the large majority of wood stoves were exempt from the no-burn days. Therefore, the removal of the exemption for EPA certified wood stoves is expected to significantly reduce PM-10 on no-burn days. This change in the exemption will also simplify enforcement of the no-bur n days as it eliminates the difficulty of pinpointing non-compliant appliance locations, especially in multi-unit buildings. This rule was adopted by the GBUAPCD and is codified in the Town of Ma mmoth Lakes regulations with the adoption of this AQMP.Mammoth Lakes AQMP

31 7.2.4 Traffic Related Control Measures

After winter storms, volcanic cinders are spread on the Town's roadways to provide additional traction and prevent vehicles from sliding on the icy roads. These cinders are crushed into ever smaller pieces by passing v ehicles. When the roads dry, vehicles kick up fine dust from the roadway. In the 1990 AQ MP, road dust was found to contribute up to 44% of the PM-10 on days that violated the federal ai r quality standard. The 1990 AQMP relied on vacuum street sweeping to re move the cinders after the roads dry and a limit on traffic volume to prev ent the problem from growing wit h the population. The traffic volume limit was set at 106,600 vehicle miles traveled on any day and is regulated through the approval of new developm ents by the Town.

In conjunction with the 2007 updat e of the Town of Mammoth Lakes General Plan, an updated traffic model was prepared. This new model incorporated additional roadway segments increasing the baseline VMT calculations.

7.2.5 Vacuum Street Sweeping.

A test of the effectiveness of the street sweeper showed t hat PM-10 emissions could be reduced by 68% after use of the Town's John son vacuum street sweepers (Satterfield, 1994b). Assuming that it takes two days to clean the heavily trafficked streets, this equates to an overall control efficiency of about 34% for street sweeping. This is consistent with the control efficiency a ssumption used in the 1990 AQMP. The 34% reduction is also consistent with the CM B analysis that found that ambient PM-10 contributions from road dust have been reduced by 32% from t he levels prior to adoption of the AQMP.

7.2.6 Traffic Volume.

To provide the most current data for this plan update, the Town of Mammoth Lakes contracted with LSC Transportation Consult ants, Inc. for an updated Vehicle Miles Traveled Analysis using a revised traffic m odel and growth projecti ons from the 2007 Town General Plan.

In 1990 a similar VMT study was completed in combination with the 1990 AQMP. The methodology used in the 1990 study and this VMT study are similar. Both studies are based on a travel demand model that assumes full buildout of the Town’s General Plan in the future. Both studies include all of t he Town’s major roadways. The main difference is the extent of the roadways analyzed in eac h study. The 1990 study had a total of 10.9 miles of roadways on 8 different roads (with 17 segments) for the existing year 1990 VMT, while the future year 2005 had a total of 15.8 miles of roadways on 10 different roads (with 31 segments). In c ontrast, the updated study’s VM T analysis included 93.1 miles of roadways on 420 different roads (with 1,037 s egments) for both the existing and future analysis years (LSC, 2012a)..Mammoth Lakes AQMP

32 To reconcile the VMT estimates, the VMT in the current TransCAD model was estimated for only those roadway segments included in the 1990 study. As shown in the right columns in Table 7-2, a total of approxim ately 80,586 existing VMT and 110,641 future VMT are estimated on those roadways included in the 1990 study. Of the total existing VMT in the current TransCAD model network (144,192), about 56 percent are reflected on the roadways included in the 1990 study. Sim ilarly, of the total future VMT in the current model (179,708), about 62 percent occur on roadways included on the 1990 study. The remaining VMT occurs on the smalle r roads that were not included in the 1990 study. Note that these figures are based on p eak-day conditions, cons istent with the 1990 study (LSC, 2012b).

The following findings are made regarding the VMT on the roadways in cluded in the 1990 Study:

 Overall, the VMT in Mammoth Lakes has increased from appr oximately 66,275 in 1990 to approximately 80,856 in 2009 based on the roadway segments evaluated in 1990. This equates to a total increase of approximately 22 percent over 19 years.

 In 1990, the forecast indicated that the existing VMT would incr ease by more than double (approximately 222 percent) by 2005. Given that the VMT in 2009 was only slightly higher than the VMT in 1990, this high rate of growth has not occurred.

 The 2005 VMT forecasts made in 1990 are mu ch higher than the 2030 forecasts in the current TransCAD model for the same roadway segments, reflecting that the growth rate has decreased since 1990 and futu re development is expected to occur at a slower rate. Based on the current TransCAD model, VMT on the roadways included in the 1990 study is expected to incr ease by a total of 37 percent from 2009 to 2030.

 The roadway segments evaluated in 1990 account for 56% of the total traffic on all roadways in the current TransCAD model for 2009 and 62% of the 2030 VMT. The Emissions Inventory in this AQMP uses all the roadway segments identified in the current TransCAD model.

It should be noted that the increase in VMT from 1990 to 2009 was spread over a larger roadway network, with the additi on of roads away from the town center. Although the additional roads contributed to an increase in VMT, they also dispersed the road dust emissions over a larger area. This meant that the increase in VMT did not affect monitored PM-10 concentrations at the Gateway Center in proportion to the increase in overall roadway emissions within the town. To a ccount for the VMT change over the current road network, the maintenance dem onstration in Chapter 8 re-examines the relationship of VMT using the current traffic model to the ambient impact at the PM-10 monitoring site.Mammoth Lakes AQMP

33 7.3 SUMMARY OF THE EFFECT OF CO NTROL MEASURES ON AMBIENT PM-10 CONCENTRATIONS

With the implementation of t he control measures from t he 1990 AQMP, PM-10 levels in the Town of Mammoth Lakes have declined significantly. The 1990 AQMP estimated 4,253 kg/day of PM-10 for t he peak 24-hour period and forecast 8,030 kg/day for the peak 24 hour total PM-10 emissions by 2005 absent any controls. (Ono et al. 1990) The updated emissions estimate shows 3,385 kg /day PM-10 in 2012, which is a 20% reduction in emissions since 1990 when th e AQMP was adopted. This reduction was achieved despite a 72% population increase from 4,785 in 1990 to 8,234 in 2010. The reduction in emissions is divided as follows:

Table 7-1. Change in Peak 24-H our In-Town Emissions 1990-2012 1990 2012 Difference RWC devices 1,839 850 -989 Road dust/cinders 2,390 2,522 132 Tailpipe, tire & brake wear 23 9 -14 Industrial (in-Town) 1 4 3 4,253 3,385 -868

7.4 AMENDMENTS TO 1990 CONTROL MEASURES

Most of the changes to the im plementing regulations of the Town of Mammoth Lakes MC 8.30 revise outdated sections or make non- substantive technical edits. The three meaningful amendments are:

 Section 8.30.040 B. This se ction is modified to clarif y that no new wood burning appliances may be installed in multi-family developments. Prohibition of new wood burning appliances in multi-fa mily projects has been the policy of the Town. The proposed revision formalizes that prac tice and implements General Plan Policy R.10.3.

 Section 8.30.080, Mandatory Curtailment. This section has been modified to include all wood burning applia nces, except pellet stoves, in the no-burn day program. Currently, EPA cert ified stoves are exempt ed under Town regulations, but are required to partici pate under the District regulations. This revision eliminates ambiguity between the Town and District regula tions and better protects the community’s air quality on those days forecast to exceed 130 micrograms per cubic meter.

 Section 8.30.100 B. This se ction sets a limit for vehicle miles traveled (VMT) within the town. The current lim it is one hundred six thousa nd six hundred (106,600) VMT on any given day. Proposed developm ent projects and other Town approved activities which affect vehicle trips ar e evaluated against this limit. Projects, programs, or policies which would cause an exceedence of this limit would haveMammoth Lakes AQMP

34 to incorporate higher levels of traffic mitigation or potentially be denied. The revised traffic model for the community incorporates additional roadway segments and revises VMT projections based on updated traffic counts and current modeling technologies. It shows and estimated VMT at General Plan buildout of one hundred seventy nine thousand seven hundred eight (179,708) for the revised model roadway segments. T he air quality modeling shows that this overall level of traffic will not cause an exceedence of the NAAQS and is s uggested as the VMT limit for the AQMP.

The full text of the amended regula tions is found in Appendix C.

7.5 ANTI-BACKSLIDING RULE - CAA SECTION 110(l)

Clean Air Act (CAA) Section 110(l) prohibits the adoption of rule revisions that would interfere with attaining the f ederal standard or making reasonab le further progress toward attainment. This is sometimes referred to as the anti-backsliding rule. The rule changes discussed in Section 7.4 were considered in the growth projections for the anticipated town buildout in the modeling analysis in Sections 8.3 and 8.4. That analysis demonstrated the rule revisions will not interfere with the attainment or maintenance of the PM-10 standard and therefor e, would comply with the CAA Section 110(l). The modeling projections demonstr ated that the highest design day concentrations would peak out at 100.0 μg/m 3 and 104.8 μg/m 3 for the high wood smoke and high road dust days, respectively. This is well below the federal standard of 150 μg/m 3

.

.Mammoth Lakes AQMP35Mammoth Lakes AQMP

36 8. Maintenance Demonstration

This section will cover the effects of increased population and visitors on PM-10 emissions on ambient PM-10 c oncentrations. Receptor mode ling results from Chapter 6 will be used with design day co ncentrations and the project ed emissions inventory to determine the future ambient PM-10 concentra tions that will result from population and visitation growth. All of the emissions and ambient PM-10 projections are based on the in-town emissions inventory, wh ich is the relevant inventory of sources that most likely contributed to PM-10 concentrations meas ured at the Gateway Center, where the samples were taken for the receptor mode ling analysis discussed in Chapter 6. The results of the receptor mode ling analysis were used for the proportional roll-back analysis that was applied for this maintenance demonstration.

8.1 EMISSIONS AND POPULATION GROWTH PROJECTIONS

The 2007 Town of Mammoth Lakes General Plan evaluated population in terms of People at One Time (PAOT). PAOT is the number of people in town on a peak winter Saturday. PAOT is expected to grow from 34,265 in 2007 to 52,000 in 2025. 2025 was considered the build out year by the General Plan. With the slowdown in development as a result of the recent recession, actual growth has been substantially le ss than forecasted. Nonetheless, the buildout number from the G eneral Plan has been used as the year 2030 projected population in both the RWC and VMT anal yses. This provides the required 10- year maintenance period with sufficient lead time to allow for redesignation.

Tables 8-1 and 8-2 show the expected PM- 10 emissions to growth with continued implementation of existing controls. T able 8-3 summarizes the peak daily PM-10 emissions for each source category for 1990, 2012, and projections to 2030. Note that the vehicle-related emissions for 2012 are based on VMT for 2009 because traffic counts showed there was little change in the aver age wintertime traffic volume between 2009 and 2013. In 2012, the average winter traffic c ount on highway 203 t he primary route in and out of the Town was about 10% lowe r than in 2009. (Caltrans, 2014)

Table 8-1. Peak Roadway Emissions Per Day 2012-2030 2012 2030 Emission Factor in g/VMT VMT Emissions VMT Emissions In-town Road Dust 17.49 144,192 2, 522 kg 179,708 3,143 kg Tailpipe,Tire & Brake Wear 0.06 144,192 9 kg 179,708 11 kg In-Town sub-total 2,531 kg 3,154 kg Out-of-town Road Dust Tailpipe,Tire & Brake Wear 17.49 0.05 53,319 53,319 933 kg 2 kg 66,452 66,452 1,162 kg 3 kg Out-of-town sub-total 935 kg 1,165 kg

Planning Area Total 3,466 kg 4,319 kgMammoth Lakes AQMP

37 Table 8-2. Peak Residential Wood Combustion Emissions Per Day 2012-2030 2012 2030 Devices Emissions Devices Emissions Non certified stoves & fireplaces 524 180 kg 64 21 kg Certified stoves 4,772 662 kg 5,569 779 kg Pellet stoves 400 8 kg 430 8 kg Total 5,696 850 kg 6,063 802 kg

Table 8-3 Peak Winter 24-hour PM-10 Emissions for Planning Area (kg/day) 1990 2012 2030 Residential Wood Combustion 1,839 850 802 Road Dust & Vehicle Emissions (In-town) 2,413 2,531 3,154 Road Dust & Vehicle Emissions (Out-of-Town) NA 935 1,165 Industrial Sources 1 8 8 Total 4,253 4,324 5,129

VMT projections for 2030 for the out-of-town emissions from traffic on Highways 203 and US 395 assume traffic will increase in proporti on to the in-town VMT increase with buildout projections from the General Plan. This is a fair assumption, since these highways are the primary route into and out of the Town of Mammoth Lakes. A secondary bypass route exists, but it receives relatively little traffic. Out-of-town vehicle em issions are not included in the maintenance demonstration in Chapter 8.3, but are incl uded in the transportation conformity budget for the planning area as discussed in Chapter 10.

PM-10 emissions generated in the Planning Area are primar ily from wood smoke from residential wood combustion and resuspended road dust. The attainment emissions inventory for Mammoth Lakes is based on esti mated daily PM-10 emissions for 2012. Emission estimates for 2012 are typical of emi ssions in the Planning Ar ea over the 3-year period (2010-2012) when PM-10 complianc e was determined from monitoring evaluations. Table 8-3 shows that total pea k daily emissions decreased from 1990 to 2012 and are currently estima ted at 3,420 pounds per day.

8.2 DESIGN DAY SELECTION FO R AMBIENT PM-10 FORECAST

For air quality planning purposes the design day concentration is the monitored PM-10 concentration that is used to determine if an ar ea is attainment with the federal standard. For PM-10 it is statistically the fourth hi ghest daily monitored concentration measured over the last three calendar years. Since PM-10 was monitored daily at the Gateway Center during 2010-2012, the fourth highest concentration ta ken from the last three years is the used as the design concentrations. Th is design concentration can then be used to forecast ambient PM-10 concentrations and future compliance with the federal PM-10 standard (see Chapter 8.3).Mammoth Lakes AQMP

38 Table 8-4 Four Highest Monitore d PM-10 Concentrations At Gateway Center, Mammoth Lakes, CA (2010-2012)

Year Number of Samples 1st Hi ( μ g/m 3 ) 2nd Hi ( μ g/m 3 ) 3rd Hi ( μ g/m 3 ) 4th Hi ( μ g/m 3 )

2010 339 101 100 99 89

2011 355 102 81 81 79

2012 330 56 53 51 48

Table 8-4 shows the four highest monitored PM-10 concentrations for the three year period from 2010 through 2012. The fourth highes t PM-10 concentration from this period, and therefore the design concentration is 99 μ g/m 3 measured on January 2, 2010. It should be noted that all of the monitor values shown in this table were measured during the winter months from December through Marc h, which is consistent with the highest PM-10 days that the AQMP is intended to mitigate.

8.3 PROPORTIONAL ROLL-BACK METHOD FOR CONTROL STRATEGY ANALYSIS

The effect of PM-10 emissions increas es or decreases on the ambient PM-10 concentration can be determined by using a linear rollback method of calculation. This method is based on the assumpti on that the ambient concentra tion due to a given source is proportional to the emissions from that source. The emissions are based on sources within the boundaries of the Town because they directly impact PM10 concentrations at the monitor site. It should be noted that the following form of the rollback equation includes background PM-10 c oncentration. The background concentration for Mammoth Lakes is about 5 μg/m 3 based on the winter time PM-10 data from Simis Ranch a sparsely populated location near Mono Lake, CA (about 20 miles north of Mammoth Lakes). The data was averaged for calm winter days that woul d be meteorologically similar to days when high PM-10 levels occur in Mammoth Lakes. The background concentration represents an ambient P M-10 concentration that is due to sources that are not accounted for in the emissions inventor y, and will not be reduced by loca l control measures. These background sources may be regi onal or global in origin.

C T = Σ C i + C b = Σ [C di (E i /E di )] + C b

C T = Total PM-10 concentration C b = Background concentration, 5 μg/m 3 C i = PM-10 concentration due to source i C di = Design day source contribution from source i E i = PM-10 emissions from source i E di = Peak PM-10 emissions from source iMammoth Lakes AQMP

39 As was described in the 1990 AQMP, Mammo th Lakes’ air pollution episodes are characterized by two different scenarios. When temperatures are lower, road dust and cinders are bound up in ice and snow and wood heating demands are higher, wood smoke is the dominant contributor to PM-10. When temperatures are warmer, melting snow and drying pavement releases road dus t and wood burning demands are lower, road dust comprises a much higher fraction of PM-10. This l eads to air pollution episodes that may be dominated by either wood sm oke or road dust. T he proportional roll-back analysis tested both cases. The results in Table 6-4 were used to estimate the contributions for the two des ign day PM10 forecasts. The high wood smoke day is based on the sample collected on 2/9/2008, which had 75% of the PM-10 attr ibuted to residential wood combustion with the remainder coming fr om road dust. The high road dust day is based on the sample collected on 2/27/2008, wh ich had 39% of the P M-10 attributed to road dust and cinders with the remainder comi ng from residential wood combustion. Due to the lack of evidence in the CMB analysis and their relatively low emissions as compared to road dust and wood smoke, some emission categories were considered negligible for the purpose of the PM-10 forecast. This include d emissions from industrial sources, tail pipes, and brake wear.

To determine the ambient source contributions for the two design day scenarios, use the following peak day 2012 emissions for E di :

E di = 850 kg/day for fireplaces and wood stoves = 2522 kg/day for In-town road dust and cinders = negligible for all other sources

For the wood burning dominated design day a ssume 75% of the des ign day concentration minus background (example, C di = 0.75 x (99 – 5) = 70.5) is due to fireplaces and woodstoves and the remainder is attr ibuted to road dust and cinders:

C di = 70.5 μg/m 3 for fireplaces and wood stoves = 18.8 μg/m 3 for road dust and tailpipe

Likewise, for the high road dust and cinders des ign day, assume 39% is attributable to road dust and cinders and the remainder is due to fireplaces and woodstoves:

C di = 57.3 μg/m 3 for fireplaces and wood stoves = 36.7 μg/m 3 for road dust and tailpipe =negligible for all other sources

Effective future emission changes on the ambient contributions can be estimated by using emissions data for 2030 as shown in table 8-3 for the variable E i

.

E i = 802 kg/day for fireplaces and wood stoves = 3,143 kg/day for in-town road dust and cinders = negligible for other sourcesMammoth Lakes AQMP

40 8.4 EFFECT OF GROWTH ON PM-10 CONCENTRATIONS

These results show that, with current control measures, growth could result in a 0.4% to a 6.5% increase in worst-case ambient PM- 10 concentrations over the next 15 years. Table 8-5 demonstrates that no exceedences of the NAAQ S for PM-10 are expected through 2050 with existing control measures. Th is is also shown in Figure 8.1. Tables 8- 6 and 8-7 and Figures 8-2 and 8-3 Show the cont ributions by source for high residential combustion days and for high road dust contribution days.

Table 8-5. Future PM-10 Concentrati ons for Residential Wood Combustion and Road Dust Design Days
2012 2030 2050*
High RWC Design Day 99.0 μg/m 3 100.8 μg/m 3 100.8 μg/m 3
High Road Dust Design Day 99.0 μg/m 3 104.8 μg/m 3 104.8/m 3
*Assumes no growth after buildout in 2030

Figure 8-1 Design Day Projection fo r High Residential Wood Combustion and Road Dust Days

0 50 100 150 200 250

1990 2012 2030 2050PM‐10μg/m3

Road Dust

Residential Wood Combustion Federal PM

‐ 10 Std. = 150 μ g/m 3Mammoth Lakes AQMP

41 Table 8-6 Forecasted PM- 10 Design Day Concentrati ons by Source for High Residential Wood Combustion Day Source Category 1990 2012 2030 2050
Background 5 μg/m 3 5 μg/m 3 5 μg/m 3 5 μg/m 3
Road Dust 5 μg/m 3 23 μg/m 3 29 μg/m 3 29 μg/m 3

Residential Wood Combustion 195 μg/m 3 71 μg/m 3 66 μg/m 3 66 μg/m 3

Vehicles* 5 μg/m 3 negligible neglig ible negligible
Industrial Sources negligible negligible negligible negligible
Total 210 μg/m 3 99 μg/m 3 100 μg/m 3 100 μg/m 3

0 50 100 150 200 250

1990 2012 2030 2050μg/m3 Figure 8-2 Design Day Projection for High Residential Wood Combustion Day

Vehicles

Residential Wood Combustion

Road Dust
Background and IndustrialMammoth Lakes AQMP

42 Table 8-7 Forecasted PM-10 Design Da y Concentrations by Source for High Road Dust Day Source Category 1990 2012 2030 2050
Background 5 μg/m 3 5 μg/m 3 5 μg/m 3 5 μg/m 3
Road Dust 93 μg/m 3 37 μg/m 3 46 μg/m 3 46 μg/m 3
Residential Wood Combustion 112 μg/m 3 57μg/m 3 54 μg/m 3 54 μg/m 3
Vehicles* negligible negligib le negligible negligible
Industrial Sources negligible negligible negligible negligible
Total 210 μg/m 3 99 μg/m 3 105 μg/m 3 105 μg/m 3
*Vehicle tailpipe and brake wear emission amount to less than 0.3 μg/m 3 except for the 1990 RWC case.

0 50 100 150 200 250

1990 2012 2030 2050μg/m3 Figure 8-3 Design Day Projection for High Road Dust Day

Vehicles

Residential Wood Combustion

Road Dust
Background and IndustrialMammoth Lakes AQMP

43 9. Contingency Plan and Maintenance Measures

9.1 CONTINGENCY PLAN REQUIREMENTS

Section 175A of the Clean Air Act requires that maintenance plans include contingency provisions to assure that any air quality vi olation of the NAAQS that occurs after the redesignation of the area as atta inment is promptly correct ed. As per guidance provided by the US EPA, (Calcagni, 1992) the maintenanc e plan should identify the measures to be adopted and a schedule and procedures for ac tion. This plan takes a two-tiered approach to address contingency measures; 1) to adopt additional measures with this plan to strengthen existing rules and to prevent NAAQS violations, and 2) to commit to adopt additional measures if the standard is violat ed in the future.

9.1.1 Additional Control Meas ures Adopted with this Plan

Section 172(c)(9) of the C AA requires that SIPs incl ude contingency measures.

Such plan shall provide for the implem entation of specific measures to be undertaken if the area fails to make reasona ble further progress, or to attain the national primary ambient ai r quality standard by the atta inment date applicable under this part. Such measures shall be included in the plan revision as contingency measures to take effect in any such case without further action by the State or the Administrator.

In subsequent NAAQS implem entation regulations and SI P approvals/disapprovals published in the Federal Register, the EPA has issued guidance that the contingency measure requirement could be sa tisfied with already adopted control measures, provided that the controls are a bove and beyond what is needed to demonstrate attainment with the NAAQS (76 FR 57891). Thus, an al ready adopted control measure with an implementation date prior to the milestone year or attainm ent year would obviate the need for an automatic trigger mechanism.

The analysis in this Plan shows that the adopted control measures for the Town of Mammoth Lakes are sufficient to maintain compliance with the NAAQS for PM-10 with a substantial buffer in the event that the measures do not fully achieve the same level of PM-10 reduction going forward that has been ac hieved to date. The Plan indicates a future design day PM-10 level of 100.8 μg/m 3 on high residential wood combustion days and 104.8 μg/m 3 (Table 8-5) on high road dust days. This is 45 μg/m 3 (30%) lower than the NAAQS of 150 μg/m 3

. Despite the attainment of the Federal NAAQ S, the Town of Mamm oth Lakes still exceeds the California 24-hour standard for PM-10. Therefore, this Plan incorporates additional measures to continue to improv e the community’s air quality.

These measures include amending the Town of Mammoth Lakes Particulate Emissions Regulations to match GBUAPC D Rule 431, requiring all w ood burning fireplaces andMammoth Lakes AQMP

44 stoves, whether certified or not, to comply with no-burn days. T hese additional measures have strengthened the existing rules and were shown by the m odeling analysis in Sections 8.3 and 8.4 that the changes will not interfere with a ttaining or maintaining compliance with the federal standard as r equired by CAA Section 110(l). Any new facilities in the Planning Area t hat may emit air pollution wil l be subject to the District’s new source review rules (209-A, 216 and 216-A). Facilities that qualify as a major source under the US EPA federal permitting guidelines will also be subject to federal PSD (Prevention of Significant Deteriorati on) permitting requirements (40 CFR 51.166 and 52.21).

9.1.2 Commitment for Addi tional Measures if t he Standard is Violated

If a monitored violation of t he federal PM-10 standard occurs in the Town of Mammoth Lakes or the surrounding nonattainment area, the Town and the District will investigate the cause of the violation(s). A violation of t he standard will be considered to be any exceedance of the P M-10 standard (150 μg/m 3 ) that causes t he annual average number of exceedances over a three year period to ex ceed 1.0 days per year; in other words, four or more exceedances in any continuous thr ee year period. The number of exceedances will exclude days that are considered to be exceptional events such as smoke from wildfires, as provided for under the EPA’s Exceptional Event Rule. (72 FR 13560)

Within 18 months of the vi olation, the Town and District will adopt additional control measures needed to meet the P M-10 NAAQS. Depending on th e cause of the violation these control measures may include the following:

 Reducing the no burn day trigger thres hold from a target of 130 to 100 μg/m 3 , if residential wood smoke is found to be a significant contributor.

 Implementing measures to reduce the use of volcanic ci nders or to improve street clean up procedures on roadways during the winter, if road dust is found to be a significant contributor.

9.2 MAINTENANCE MEASURES

CAA Sec 175A and US EPA guidance (Calcagni, 1992) require additional measures in the maintenance plan to tra ck the progress of the plan, and to continue air quality monitoring.

9.2.1 Triennial Progress Reports

The US EPA requires areas to track the progress of main tenance plans. (Calcagni, 1992) This would include updating t he emissions inventory, assessi ng air quality trends and reevaluating modeling assumptions. The Town and the District will commit to submitting progress reports every third year starting in 2017 to track the progress of the maintenance plan. Progress reports will in clude an update on PM-10 air quality, a revised peak daily emission inventory for all s ources in the planning area, a reassessment of the modeledMammoth Lakes AQMP

45 air quality trend using the modeling assumptions in Section 8.3, and addi tional information that may be relevant to the air quality program in the Town.

9.2.2 Commitment to Cont inue PM-10 Monitoring

The District will continue to maintain monito ring network integrity and, with the Town, continue to monitor PM-10 in accordance with 40 CFR Part 58, (1) to ve rify the attainment status of the area as requi red by the US EPA (CAA Sec 175A, Calcagni, 1992) and (2) to implement the no burn day program, which re lies on daily PM-10 monitoring. Although the intention is to continue monitoring indefin itely in order to im plement the no burn day program, the Town and the District will commit to continue ambient PM-10 monitoring for at least 20 years following the redesignation of the area to a ttainment in order to comply with CAA Sec 175A(b).

9.3 CONTINGENCY AND MAINTENANCE PLAN CONCLUSIONS

The success of the existing control measures demonstrates that PM-10 concentrations have been significantly reduced to a level that contingency m easures are not required to maintain compliance with the f ederal standard. Nonetheless, additional measures have been incorporated into the AQMP to assist in further reductions of PM-10 levels with the goal of improved compliance with the California Ambient Air Qu ality Standard for PM-10. These additional measures have strengthened the existing rules and as such are consistent with CAA Section 110(l) to avoid adopting measures that would interfere with attainment of the federal standard. The Town and the District will commit to the continuation of the air qualit y program in the Mammoth Lak es through the implementation of control measures, performing ambient m onitoring and providin g periodic updates on the progress of the Plan.Mammoth Lakes AQMP

46 10. Transportation Conformity

10.1 BACKGROUND

Transportation conformity is a way to ensure that Federal funding and approval are given to those transportation activiti es that are consistent with ai r quality goals. It ensures that these transportation activities do not worsen ai r quality or interfere with the "purpose" of the SIP, which is to meet the NAAQS. Meeting the NAAQS often requires emissions reductions from mobile sources.

According to the Clean Air Act, transporta tion plans, programs, and projects cannot:

 Create new NAAQS violations;

 Increase the frequency or severity of existing NAAQS violations; or

 Delay attainment of the NAAQS.

Transportation conformity requirements contai ned in Great Basin Unified Air Pollution Control District Regulation XII require that federal actions and federally funded transportation projects conform to SIP rules and that they do not interfere with efforts to attain federal air quality standar ds. Transportation sources we re found to contribute to the nonattainment problem in Mammoth Lak es and PM-10 from paved roads. Peak winter-time emissions from road dust and vehi cle emissions were estimated at 3,466 kilograms per day in the Mammoth Lakes Pl anning Area (see Table 8-1). This includes 2,531 kg/day in the Town of Mammoth Lak e and 935 kg/day outside of the Town on Highways 203 and US 395. Future PM-10 emission projections for 2030 and beyond is for road dust and vehicle emi ssions to increase to 3,154 kg /day in the Town and 1,165 kg/day outside of the Town (see Table 8-3).

In terms of transportation plans and transpor tation improvement programs (TIPs), FHWA/Federal Transit Administration’s jo int conformity determination is based on a quantitative demonstration that projected motor vehicle em issions from the planned transportation system do not exceed the motor vehicle emissions budget established in the SIP. If the transportati on plan or TIP cannot meet t he motor vehicle emissions budget, then changes may be needed to the transportation plan or TIP, or the SIP. If conformity is not determined according to the timeframes established in the regul ations, a conformity "lapse" will occur. When conformity lapses, F ederal projects may proc eed only if they are exempt from transportation confo rmity (e.g., safety projects ), TCMs in an approved SIP, or project phases that have already rece ived funding commitments by FHWA or FTA.

10.2 PLANNING ASSUMPTIONS

Forecasts in this plan are based on the proj ections in the Town of Mammoth Lakes General Plan. Both growth in VMT and changes in the numbers of residential wood burning appliances assume fu ll build-out of the community at the maximum densities identified in the G eneral Plan. To be consistent with th is plan, analyses should be basedMammoth Lakes AQMP

47 on projected peak daily wintertime emissions in the Town and average daily wintertime (January-March) emissions on Highways 203 and US 395 outside of the Town, but within the boundaries of t he planning area.

Motor Vehicle Emissions Budget

The motor vehicle emissions for in-town traf fic is based on the build-out assumptions contained in the Town of Mammoth Lakes Gener al Plan. As set forth in the Mammoth Lakes Vehicle Miles Traveled Analysis (LSC , August, 2012) for the year 2030, traffic volume in Mammoth Lakes will reach 179,708 VMT per day, producing 3,154 kg of PM10.

Emissions projections for 2030 for out-of- town traffic on Highways 203 and US 395 assume traffic will increase in proportion to the in-town VMT increase with buildout projections from the General Plan. This is a fair assumption, since these highways are the primary route into and out of the Town of Mammoth Lakes. A secondary bypass route exists, but it receives relatively little tr affic. For the year 2030 and beyond, average wintertime traffic on these out-of town high ways may increase from 53,319 in 2012 to 66,452 vehicle miles travelled per day in 2030, producing 1,165 kg/day of PM-10 emissions.

Combining the in-town and out-of-town future wintertime emissions for 2012 results in an overall motor vehicle emission budget of 3, 466 kg per day and for 2030 yields the overall motor vehicle emissions budget for the planni ng area of 4,319 kg per day. Projects that may result in wintertime emissions in exce ss of these budgets shall incorporate measures to reduce emissions or revise the AQMP to demonstrate through additi onal controls or other methods that the increase in emissions will not result in a violation of the NAAQS for PM-10.Mammoth Lakes AQMP

48 11. General Conformity

General conformity is the f ederal regulatory process for pr eventing major federal actions or projects from inte rfering with air quality pl anning goals. Conformity provisions ensure that federal funding and approval are given only to those activities and projects that are consistent with state air qua lity implementation plans (SIP s). Conformity with the SIP means that major federal actions will not cause new air quality violations, worsen existing violations, or delay timely attain ment of the national ambient air quality standards (NAAQS). Current federal rules require that federal agencies use the emissions inventory from an approved SIP’s a ttainment or maintenance demonstration to support a conformity determination.

General conformity requirements contained in District Regulation XIII require that federal actions and federally funded projects conform to SIP rules and that they do not interfere with efforts to atta in federal air quality standards. A conformity determination is currently required for any federally funded ( non-transportation) project or action that takes place in a moderate PM-10 nonattain ment and maintenance areas that have the potential to exceed a de minimis PM-10 emissions threshold of 100 tons per year. In order to maintain the stringency of cont rol requirements in the Mammoth Lakes Planning Area under a maintenance plan, the District will retain the 100 tons of PM-10 per year de minimis emissions threshold for triggeri ng a conformity determination as currently required under District Regulation XIII.Mammoth Lakes AQMP

49 12. Redesignation Request

States may ask U.S. EPA to r edesignate an area “attainment” if:

 the area has monitored attainment of the air quality standard;

 the area has a fully approved St ate Implementation Plan;

 U.S. EPA has determined that the improvem ent in air quality is due to permanent and enforceable reductions in emissions;

 the state has submitted, and U.S. EPA has approved, a maintenance plan for the area; and,

 the area has met all other applicab le federal CAA requirements.

As described in Chapter 8, the Town of Mammoth Lakes last exceeded the federal PM10 24-hour standard in 1994. Attainment of the PM-10 standard is a direct result of the implementation of control meas ures by the Town of Mammoth Lakes as described in the 1990 Air Quality Management Plan fo r the Town of Mammoth Lakes.

The daily data collected by the Great Basin Unified Air Pollution Control District in Mammoth Lakes demonstrates that no more than 1.0 exceedances of the NAAQS have occurred over the last three years as is requ ired to demonstrate attainment of the federal standard. In fact, t he data show that there have been no exceedances during the last 19 years.

Applying a proportional roll back analysis to the PM-10 present and future emissions this document demonstrates that no more than 1.0 exceedances per year would be expected through the next 20 year planning period and bey ond. With continued implementation of the control measures, attain ment will be maintained.

The District finds that the Mammoth Lakes PM-10 Planning Area has attained the federal PM-10 standard and requests the Ca lifornia Air Resources B oard recommend to the US Environmental Protection Agency that the area be redesignated from nonattainment to attainment with the f ederal PM-10 standard.Mammoth Lakes AQMP

50 13. References

52 FR 24634. Federal Register, Revisions to the National Ambient Air Quality Standards for Particulate Matter , July 1, 1987.

52 FR 29384. Federal R egister, August 7, 1987.

62 FR 38652. Federal Register, National Ambient Air Qualit y Standards for Particulate Matter , July 18, 1997.

71 FR 61144-64233. Federal Register, National Ambient Air Quality Standards for Particulate Matter 10/17/06.

72 FR 13560. Federal Register, Treatment of Data Influence by Exceptional Events

, March 22, 2007.

76 FR 57891. Federal Register, Approval of Air Quality Implementation Plans; South Coast Attainment Plan for 1997 8-hour Ozone Standard , September 16, 2011.

Calcagni, 1992. Calcagni, John, Procedures for Processing Requests to Redesignate Areas to Attainment , US EPA, September 4, 1992.

Caltrans, 2014. Traffic Counts on Highways 203 and US 395 in Mammoth Lakes Planning Area (1993-2013) , Caltrans, March 27, 2014.

CARB, 1997. Entrained Road Dust from Paved Road Travel, California Air Resources Board, July 2, 1997.

CARB, 2013a. Area Designations Maps / State and National, 4/22/13

, website accessed May 2, 2013, www.arb.ca.gov, 4/22/13.

CARB, 2013b. Ambient Air Quality Standards, California Air Resources Board, web site accessed June 4, 2013, http://www.arb.ca.gov/research/aaqs/caaqs/pm/pm.htm

. CARB, 2014. Mobile Source Emissions Inventory using EMFAC2011, last updated January 2013, California Air Resources Boar d, website accessed March 28, 2014, http://www.arb.ca.gov/emfac/

. EPA, 2013. National Ambient Air Qualit y Standard for Particulates , US EPA, website accessed May 2, 2013, www.epa.gov/ttn/naaqs/standards/pm/s_pm_index.html

. EPA, 2014. Air Quality System , US EPA, website accessed March 14, 2014, http://www.epa.gov/ttn/airs/airsaqs/

. EPA, 2013. Emissions Factors & AP 42, Compilation of Air Pollutant Emission Factors , Last Updated December 28, 2011, US EPA, website accessed June 15, 2013, www.epa.gov/ttn/chief/ap42/index.html.Mammoth Lakes AQMP

51 Daugherty, 2013. Jennifer Daugherty, Associ ate Planner, Town of Mammoth Lakes, personal communication.

Davis and Read, 1989. Guidance Document for Resident ial Wood Combustion Emission Control Measures , 1989.

DRI, 2013. Chemical Analysis of PM10 and PM 2.5 Filters from Mammoth Lakes , Desert Research Institute Division of Atmospher ic Sciences, Reno, Nevada, May 21, 2013.

GBUAPCD, 2014. Great Basin Unifi ed Air Pollution Control District, Permitted Particulate Matter Sources Within the Mammoth Lakes AQMP , March 2014.

Kusumoto, 2007 and 2013. Scott Kusumoto , Inyo National Forest, personal communication.

LSC, 2012a. Mammoth Lakes Vehicle Miles Traveled Analysis , Sara Hawley and Leslie Suen, LSC Transportation Consultants, Inc ., Tahoe City, California, August 3, 2012.

LSC, 2012b. Mammoth Lakes Vehicle Miles Trav eled Analysis – Comparison with 1990 Study , Sara Hawley and Leslie Suen, LSC Trans portation Consultants, Inc., Tahoe City, California, September 10, 2012.

OAQPS, 2005. Review of the National Ambient Air Quality Standards for Particulate Matter: Policy Assessment of Sci entific and Technical Information . U.S. Environmental Protection Agency Office of Air Quality Plan ning and Standards, Research Triangle Park, North Carolina, December, 2005

Ono, 1990. Ono, Duane, William Taylor and Debra Lawhon, (1990) , Air Quality Management Plan for the To wn of Mammoth Lakes, Great Basin Unified Air Pollution Control District and the Town of Mammoth Lakes, Bishop, CA, November 30, 1990.

Satterfield, 1994a. No Burn Day Compliance Study for the Town of Mammoth Lakes, California , Charles G. Satterfield, Satterfield & A ssociates, June Lake, California, June 16, 1994.

Satterfield, 1994b. Street Sweeper Efficiency Study for the Town of Mammoth Lakes

, Charles G. Satterfield, Satterfield & Associ ates, June Lake, California, June 13, 1994.

Town of Mammoth Lakes, 2007a. Town of Mammoth Lakes General Plan, 2007.

Town of Mammoth Lakes, 2007b. Final Environmental Impact Report for the Town of Mammoth Lakes 2005 G eneral Plan Update, 2007.

Town of Mammoth Lakes, 2013. Buildi ng Permit Records as of 6/30/13.Mammoth Lakes AQMP



# Appendix A

Glossary1 

## Glossary

AAQS (Ambient Air Quality St andards): H ealth and welf are based standards for clean outdoor air that identify t he maximum acceptable average concentrations of air pollutants during a specified period of time. (See NAAQS)

Air Pollutants: Amounts of foreign and/ or natural substances occurring in the atmosphere that may result in adverse e ffects on humans, animals, vegetation, and/or materials.

Ambient Air: The air occurring at a particular time and place outside of structures. Often used interchangeably wit h "outdoor" air.

APCD (Great Basin Unif ied Air Pollution Control Distric t): The regional agency with authority to regulate stationary, indirect, an d area sources of air pollution (e.g., power plants, highway construction, and housing dev elopments) within Inyo, Mono, and Alpine counties, and governed by a district air po llution control board composed of the elected county supervisors and representatives of cities within the district.

AQMP (Air Quality Management Plan): A Plan prepared by an APCD, for a county or region designated as a nonattain ment area, for the purpose of bringing the area into compliance with the requirements of the nati onal and/or California Ambient Air Quality Standards. AQMPs designed to attain nati onal ambient air quality standards are incorporated into the Stat e Implementation Plan (SIP).

Attainment: Compliance with the Natio nal and/or California Ambient Air Quality Standards (NAAQS OR CAAQS).

CAA (Federal Clean Air Act): A federal law passed in 1970 and amended in 1977 and 1990 which forms the basis for the national air pollution control effort. Basic elements of the act include national ambient air quality st andards for major air po llutants, air toxics standards, acid rain control meas ures, and enforcement provisions.

California Ambient Air Quality Standard: Standards set by the State of California for the maximum levels of air pollutants which can exist in the outdoor ai r without unacceptable effects on human health or the public welfare. These are generally more stringent than NAAQS.

CARB (California Air Resource s Board): The Stat e's lead air quality agency, consisting of a nine-member Governor- appointed board. It is responsible for attainment and maintenance of the State and fe deral air quality standards, and is primarily responsible for motor vehicle pollution control. It oversees county and regional air pollution management programs.

Emission Standard: The maximum amount of a pollutant that is allowed to be discharged from a polluting source such as an automobile or chimney.2 GBUAPCD: The Great Basin Unif ied Air Pollution Control District.

Indirect Source: Any facility, building, stru cture, or installation, or combination thereof, which generates or attracts mobile source activity that results in emissions of any pollutant (or precursor). Examples of indirect sources include employment sites, shopping centers, housing de velopments, airports, commercial and industrial development, and parking lots and garages.

Maintenance Plan: In general, a plan that det ails the actions necessary to maintain air quality standards. In particular, the federal Clean Air Act requires maintenance plans for areas that have been redesignat ed as attainment areas.

Mobile Sources: Moving sources of air pollution such as automobiles, motorcycles, trucks, off-road vehicles, boats and airplanes.

NAAQS (National Ambient Air Quality Standards): Standards set by the federal U.S. EPA for the maximum levels of air pollutants which can exist in the outdoor air without unacceptable effects on human heal th or the public welfare.

Nonattainment Area: A geograp hic area identified by the U.S. EPA and/or CARB as not meeting either NAAQS or CAAQ S standards for a given pollutant.

PM (Particulate Matter): Solid or liquid particles of soot, dust, smoke, fumes, and aerosols.

PM-10 (Particulate Matter less than 10 microns): A major air pollutant consisting of tiny solid or liquid particles of soot, dust, sm oke, fumes, and aerosols. The size of the particles (10 microns or smaller, about 0.0004 inches or less) allows them to easily enter the air sacs in the lungs where they may be deposited, resulting in adverse health effects. PM-10 also causes visibility reduction and is a criteria air pollutant.

PM-2.5 (Particulate Matter le ss than 2.5 microns): A majo r air pollutant consisting of tiny solid or liquid particles, generally soot and aerosols. The size of the particles (2.5 microns or smaller, about 0.0001 inches or less) allows them to easily enter the air sacs deep in the lungs where they may cause adverse health effects, as noted in several recent studies. PM2.5 also causes visibility reduction,

SIP (State Implementation Plan): A document prepared by each state describing existing air quality conditions an d measures which will be taken to attain and maintain national ambient air qualit y standards (see AQMP).

Smoke: A form of air pollution consisting primar ily of particulate matte r (i.e., particles). Other components of smoke in clude gaseous air pollutant s such as hydrocarbons, oxides of nitrogen, and car bon monoxide. Sources of smok e may include fossil fuel combustion, agricultural burning, and other combustion processes.3 Stationary Sources: Non-mobile source s such as power plants, refineries, and manufacturing facilities which emit air pollutants; can include area sources depending on context.

U.S. EPA (United States Envi ronmental Protection Agency) : The federal agency charged with setting policy and guidelines, and carrying out legal mandates for the protection of national interest s in environmental resources.

VMT: Total vehicle miles traveled by all or a subset of mobile sources.

Visibility: The distance that atmospheric conditions allow a person to see at a given time and location. Visibility reduction from ai r pollution is often due to the presence of sulfur and nitrogen oxides, as well as particulate matter.M ammoth Lakes AQMP



# Appendix B

Residential Wood Burning Survey 2013 SummaryHome Heating Survey Summary Report:

Prepared by: Megan Rybacki, Planning Intern

The home heating survey was sent to over 6,000 out-of-town property owners, 4,500 Town P.O. Box holders and 200 private P.O. boxes. Out of these 10,700 property ow ners and renters there were 574 respondents to the survey. The variety of respondents whom participated in th e survey gives the town an accurate snapshot of data that can be used to analyze the community’s home heating habits.

Over 85% of the respondents indicated that they owned property in Mammoth Lakes and 75% of these homeowners purchased their homes after the woodstove ordina nce was put into effect in 1990. Of the indicated property owners there were 295 condo miniums, 178 single family homes and approximately 44% these property owners consider themselves full time occupants during the winter months of November through March. The remaining 15% of the survey respondents indicated that they were renters and 92% of these renters consider themselves full occupants during the winter months of November-March. The rental residence respondents include 30 condominiums, 28 apartments, 27 single family homes and 1 mobile home.

Only 156 (28%) of the survey respondents indicated that a wood burning appliance was their homes primary source of heat. Out of these primary wood burning res ponses 50% are operating a wood burning appliance and over 25% are operating a pellet burning appliance. 34 people are operating an EPA phase II appliance, while another 34 are operating an EPA phase I appliance, 24 people are operating a fireplace with an insert, and 13 people are operating a non-compliant woodstove or fireplace. The majority of these respondents are using approximately 1-3 cords of wood per average winter season.

Over 77% of the survey participants are using an altern ative home heating device as their primary source of heat, including various propane devices as the most specified appliance.

General findings show that 93% of the respondents ar e only burning dry wood, however 3 respondents admitted to burning their trash. Other poor burning techniques were revealed in this process. Based on these responses and a significant number of respondents whom indicated inter est in becoming educated on the proper techniques of burning, I believe that it would be beneficial for the to wn to produce educational information on burning wise and specify items that are detrimental to the air qualit y and their home heating appliance when burned.

In addition to these findings the Town’s cinder “concerns” were validated by many of the respondent’s suggestions that the usage and maintenance of cinders used on the town’s roadways is a large factor in generating poor air quality. Based on the survey results and the findi ngs that will be identified in the air filter analysis, it could become beneficial for the town to analyze cinde r usage and begin to consider other de-icing agents.

Almost 80% of the respondents were aware that the town issues no burning and burning curtailment days. Over 200 full time and part time residents also concluded that they would like to become a part of the Air Quality Notify Me list.

In conclusion of the survey results, gathered changeout data, public outreach strides, and fewer federal air quality regulation compliance issues it is evident that the Town has taken great strides to begin to meet more stringent air quality state regulations. Attached are informative gra phs and raw data generated from the survey results.Home	Heating	Survey

1	/	21 85.14% 487

14.86% 85 

### Q1 Do	you	own	or	rent	your	property in	Mammoth?

Answered:	572	 Skipped:	0

0% 20% 40% 60% 80% 100% Own

Rent

Own

Rent

Total 572 Answer	Choices ResponsesHome	Heating	Survey

2	/	21 25.62% 124

74.38% 360 

### Q2 Have	you	owned	your	property since	before	1990?

Answered:	484	 Skipped:	88

0% 20% 40% 60% 80% 100% Yes

No

Yes

No

Total 484 Answer	Choices ResponsesHome	Heating	Survey

3	/	21 0% 0

64.46% 312

26.24% 127

9.30% 45 

### Q3 Have	you	replaced	or	installed your	woodstove	or	home	heating device	with	a	new	model	after	1990?

Answered:	484	 Skipped:	88

0% 20% 40% 60% 80% 100% I	don't	know

Yes

No

I	don't	know

I	don't	know

Yes

No

I	don't	know

Total 484 Answer	Choices ResponsesHome	Heating	Survey

4	/	21 0% 0

16.99% 96

23.54% 133

8.67% 49

6.73% 38

44.07% 249 

### Q4 How	often	is	your	property occupied	during	November-March?

Answered:	565	 Skipped:	7

0% 20% 40% 60% 80% 100% Never

Less	than	30 days

1-2	months

2-3	months

3-4	months

Full	time occupancy

Never

Less	than	30	days

1-2	months

2-3	months

3-4	months

Full	time	occupancy

Total 565 Answer	Choices ResponsesHome	Heating	Survey

5	/	21 36.17% 204

5.50% 31

57.45% 324

1.24% 7

0% 0 

### Q5 What	type	of	residence	do	you own	or	rent?

Answered:	564	 Skipped:	8

0% 20% 40% 60% 80% 100% Single	family home

Rental apartment

Condominium

Mobile	home

Other	(please specify)

Single	family	home

Rental	apartment

Condominium

Mobile	home

Other	(please	specify)

Total	Respondents: 564 Answer	Choices ResponsesHome	Heating	Survey

6	/	21 27.76% 156

67.62% 380

4.63% 26 

### Q6 Is	a	pellet	or	wood	burning device	your	home's	primary	source of	heat?

Answered:	562	 Skipped:	10

0% 20% 40% 60% 80% 100% Yes

No

Not applicable

Yes

No

Not	applicable

Total 562 Answer	Choices ResponsesHome	Heating	Survey

7	/	21 44.13% 248

12.63% 71

77.05% 433 

### Q7 What	type	of	heating	device	do you	use	to	heat	your	home?	(	Please select	multiple	answers	if applicable.)

Answered:	562	 Skipped:	10

0% 20% 40% 60% 80% 100% Wood	burning device

Pellet burning device

Other

Wood	burning	device

Pellet	burning	device

Other

Total	Respondents: 562 Answer	Choices ResponsesHome	Heating	Survey

8	/	21 27.08% 65

32.50% 78

29.17% 70

11.25% 27 

### Q8 Please	identify	the	type	of	wood burning	appliance	you	use.

Answered:	240	 Skipped:	332

0% 20% 40% 60% 80% 100% Fireplace with	insert

EPA	certified woodstove (Phase	1)

EPA	certified woodstove (Phase	2)

Non-certified stove	or fireplace

Fireplace	with	insert

EPA	certified	woodstove	(Phase	1)

EPA	certified	woodstove	(Phase	2)

Non-certified	stove	or	fireplace

Total 240 Answer	Choices ResponsesHome	Heating	Survey

9	/	21 97.20% 104

62.62% 67 

### Q9 If	you	are	able,	please	identify the	make	and	model	of	your	wood burning	appliance.

Answered:	107	 Skipped:	465

Make:

Model:

Total	Respondents: 107 Answer	Choices ResponsesHome	Heating	Survey

10	/	21 48.32% 115

21.85% 52

13.45% 32

11.76% 28

4.62% 11 

### Q10 How	many	cords	of	wood	do	you burn	in	an	average	winter	season? (A	cord	is	understood	to	be	128 cubic	ft.	of	wood	or	wood	stacked	to be	4ft	x	4ft	x	8ft.)

Answered:	238	 Skipped:	334

0% 20% 40% 60% 80% 100% Less	than	1 cord

1-2	cords

2-3	cords

3-4	cords

5	or	more cords

Less	than	1	cord

1-2	cords

2-3	cords

3-4	cords

5	or	more	cords

Total 238 Answer	Choices ResponsesHome	Heating	Survey

11	/	21 31.51% 75

59.24% 141

9.24% 22 

### Q11 How	do	you	obtain	your firewood?

Answered:	238	 Skipped:	334

0% 20% 40% 60% 80% 100% Cut	yourself

Purchase from...

Other	(please specify)

Cut	yourself

Purchase	from...

Other	(please	specify)

Total	Respondents: 238 Answer	Choices ResponsesHome	Heating	Survey

12	/	21 63.57% 89

0.71% 1

4.29% 6

17.14% 24

22.14% 31 

### Q12 Where	do	you	purchase	your firewood	from?

Answered:	140	 Skipped:	432

0% 20% 40% 60% 80% 100% Greg Cook/Mammoth Firewood...

High	Country Lumber

Do	it	Center

Out	of	town

Other	(please specify)

Greg	Cook/Mammoth	Firewood	Company

High	Country	Lumber

Do	it	Center

Out	of	town

Other	(please	specify)

Total	Respondents: 140 Answer	Choices ResponsesHome	Heating	Survey

13	/	21 1.30% 3

3.46% 8

14.29% 33

28.57% 66

52.38% 121 

### Q13 How	long	is	your	wood seasoned	before	you	burn	it?

Answered:	231	 Skipped:	341

0% 20% 40% 60% 80% 100% A	week

A	few	weeks

A	couple months

3-6	months

6	months	to over	a	year

A	week

A	few	weeks

A	couple	months

3-6	months

6	months	to	over	a	year

Total 231 Answer	Choices ResponsesHome	Heating	Survey

14	/	21 30.30% 70

22.51% 52

47.19% 109 

### Q14 How	many	days	do	you	burn wood	during	a	typical	winter	month?

Answered:	231	 Skipped:	341

0% 20% 40% 60% 80% 100% 1-10	days

10-20	days

20-30	days

1-10	days

10-20	days

20-30	days

Total 231 Answer	Choices ResponsesHome	Heating	Survey

15	/	21 92.64% 214

1.30% 3

0% 0

8.66% 20 

### Q15 Do	you	burn	anything	other than	dry	wood	in	your	stove?

Answered:	231	 Skipped:	341

0% 20% 40% 60% 80% 100% I	only	burn dry	wood

Trash

Coal

Other	(please specify)

I	only	burn	dry	wood

Trash

Coal

Other	(please	specify)

Total	Respondents: 231 Answer	Choices ResponsesHome	Heating	Survey

16	/	21 46.77% 29

29.03% 18

14.52% 9

9.68% 6 

### Q16 How	many	bags	of	pellets	do you	use	in	an	average	winter season?	(A	pallet	of	pellets	equals	1 ton	and	there	are	50	bags	in	a	ton. One	bag	is	equal	to	40lbs.)

Answered:	62	 Skipped:	510

0% 20% 40% 60% 80% 100% Less	than	50 bags

50-75	bags

75-100	bags

more	than	100 bags

Less	than	50	bags

50-75	bags

75-100	bags

more	than	100	bags

Total 62 Answer	Choices ResponsesHome	Heating	Survey

17	/	21 47.04% 119

63.64% 161

0.40% 1

15.02% 38 

### Q17 Please	specify	your	alternative heat	source.	(Please	select	all choices	that	apply.)

Answered:	253	 Skipped:	319

0% 20% 40% 60% 80% 100% Electric heating device
Propane	gas heating device	(ga...

Geothermal/So lar	heating device

Other	(please specify)

Electric	heating	device

Propane	gas	heating	device	(gas	fireplace,	insert,	logs,	etc,.)

Geothermal/Solar	heating	device

Other	(please	specify)

Total	Respondents: 253 Answer	Choices ResponsesHome	Heating	Survey

18	/	21 79.48% 430

20.52% 111 

### Q18 Are	you	aware	that	the	town calls	no	burn	days	when	the	air quality	is	forecasted	to	be	poor?

Answered:	541	 Skipped:	31

0% 20% 40% 60% 80% 100% Yes

No

Yes

No

Total 541 Answer	Choices ResponsesHome	Heating	Survey

19	/	21 32.16% 174

40.30% 218

40.30% 218 

### Q19 Would	you	be	interested	in improving	the	air	quality	in Mammoth	Lakes?

Answered:	541	 Skipped:	31

0% 20% 40% 60% 80% 100% Not interested

I	would	like to	become more	educa...

I	would	like to	receive email	or	t...

Not	interested

I	would	like	to	become	more	educated	in	proper	burning techniques.

I	would	like	to	receive	email	or	text	updates	on	burning restrictions	and	no	burn	days.

Total	Respondents: 541 Answer	Choices ResponsesHome	Heating	Survey

20	/	21 27.78% 150

23.33% 126

46.30% 250

24.26% 131

10.37% 56 

### Q20 If	the	town	developed	a program	to	reduce	emissions	I would	be	interested	in	participating in	the	following	choices...

Answered:	540	 Skipped:	32

0% 20% 40% 60% 80% 100% Not interested

A	woodstove changeout program

Home weatherizatio n	program

Educational outreach program

Other	(please specify)

Not	interested

A	woodstove	changeout	program

Home	weatherization	program

Educational	outreach	program

Other	(please	specify)

Total	Respondents: 540 Answer	Choices ResponsesHome	Heating	Survey

21	/	21 100% 490

0% 0

100% 490

61.22% 300

0% 0

0% 0

0% 0

0% 0

97.76% 479

100% 490 

### Q21 Thank	you	for	completing	the home	heating	survey.	Enter	the following	information	for	a	chance to	win	a	Von's	gift	card!	(Please enter	physical	address	and	include unit	number	to	ensure	that	the Town	does	not	receive	duplicate entries.	Please	provide	your	name for	your	chance	to	win	$150	gift	card

to	Von's.)

Answered:	490	 Skipped:	82

Name:

Company:

Address:

Address	2:

City/Town:

State:

ZIP:

Country:

Email	Address:

Phone	Number:

Total	Respondents: 490 Answer	Choices ResponsesMam moth Lakes AQMP



# Appendix C

Town of Mammoth Lakes Municipal Code Chapter 8.30 (Revised)Town of Mammoth Lakes Municipal Code

Chapter 8.30 Particulate Emissions Regulations

Sections: 8.30.010 - Purpose. 8.30.020 - Definitions. 8.30.030 - Standards for r egulation of solid f uel burning appliances. 8.30.040 - Limitations on number of appliances. 8.30.050 - Replacement of noncertified appliances upon sale of property. 8.30.060 - Opacity limits. 8.30.070 - Prohibited fuels. 8.30.080 - Mandatory curtailment. 8.30.090 - Pollution reducti on education programs. 8.30.100 - Road dust reduction measures. 8.30.110 - Fees. 8.30.120 - Penalties.

8.30.010 - Purpose.

The purpose of this chapter is to improve and ma intain the level of air quality of the town so as to protect and enhance the health of its citizens by controlling the emissions of particulate matter into the air of the community of Mammoth Lakes.

8.30.020 - Definitions.

For the purpose of this chapter:

A. "EPA" means the United States Environmental Protection Agency.

B. "EPA-certified appliance" means any wood or other solid fuel burning appliance for space or water heating or cooking that m eets the Phase II performance and emission standards of the Environmental Protection Agency. Phase II requirements are 4.1 grams per hour particulate emission for cata lytic appliances and 7.5 grams per hour for noncatalytic appliances. Pellet fueled wood heaters and EPA Phase II qualified fireplaces and fireplace retrofit devices shall be considered as meeting Phase II requirements. All other solid fuel burning appliances shall be cons idered noncertified.

C. “Opacity” means the amount of light obscur ed by particulate matter in the air as may be measured using EPA Method 9 (40 CFR 60, App. A).

D. "Pellet fueled wood heater" means any heat er designed to heat the interior of a building that operates on pelletized wood and has an automatic feed.E. "Permanently inoperable" means modified in such a way that the appliance can no longer function as a solid fuel appliance or easily be remodified to function as a solid fuel appliance. Permanent conversion to other fuels, such as gas, is permitted.

F. "Solid fuel burning applianc e, heater or device" means any fireplace, wood burning heater or coal stove or stru cture that burns wood, coal or any other nongaseous or nonliquid fuels, or any similar device burning any solid fuel used for aesthetic, water heating, or space heating purposes.

8.30.030 - Standards for r egulation of solid f uel burning appliances.

A. No solid fuel burning appliance shall be permitted to be insta lled within the town unless the appliance is certified as meeti ng the emission require ments of the U.S. Environmental Protection Agency ( EPA) for Phase II certification.

B. The restrictions of this section shall appl y to all solid fuel burning appliances including unregulated fireplaces.

C. For the purposes of enfor cing this chapter, the Town shall keep a record of all certified appliances installed in Mammoth La kes in accordance with this chapter and of properties which have been determined to conform to the requirements of this chapter.

8.30.040 - Limitations on number of appliances.

A. Single Family Dwellings. No more than one EPA-certified appliance may be installed in any new single family detached dwelling. Existing properties with one or more existing solid fuel burning appliances may not install additional solid fuel burning appliances. One pellet fueled wood heater per dwelling shall be allowed in addition to the one EPA-certified appliance.

B. Multi-Unit Residential De velopments. No solid fuel burning appliance may be installed in any new multi- unit residential development; however, one pellet fueled wood heater per dwelling may be installed in a multi-uni t residential development.

C. Commercial or Lodging Developments. No solid fuel burning appliance shall be installed in any new commercial or lodging development project.

D. Solid fuel burning appliances shall not be considered to be the primary form of heat in any new construction.

E. No new and replacement appliances shal l be installed without first obtaining a building permit from the Town . All installations shall require an inspection and approval by the building division prior to operation.

F. Verification of compliance shall be certif ied by an inspector of the Town’s building division.8.30.050 - Replacement of noncertified appliances upon sale of property.

A. Prior to the completion of the sale or tr ansfer of a majority in terest in any developed real property within the town, all existing noncertified solid fuel burning appliances shall be replaced, removed, or rendered permanent ly inoperable. If the buyer assumes responsibility for appliance repl acement or removal in writing on a form approved by the Community and Economic Development Director, the deadline for such action shall be extended to 60 calendar days from the date of completion of the sale or transfer. The buyer shall contact the building division no la ter than 60 calendar da ys from the date of completion of sale to schedule an inspection.

B. The building division shall inspect the appliance(s) in question to assure that they meet the requirements of this chapter. Within five wo rking days from the date of the inspection, the building division shall issu e a written certification of compliance or noncompliance for the affected property. If the inspection reveals that the subject property does not comply with the requirement s of this chapter, all noncomplying solid fuel burning appliances shall be replac ed, removed, or rendered permanently inoperable. In this event, reinspection sha ll be required prior to certification of compliance.

C. No building permit shall be issued for an in crease in habitable area of a structure that has not complied with the requi rements of this section.

D. Existing appliances cert ified as meeting EPA Phase I requirements or Oregon Department of Environmental Quality require ments are not subject to the replacement requirements.

E. Pursuant to Section 1102.6(a) of the California Civil Code, sellers of residential real property shall disclose to purchasers of such property the provisio ns of this chapter. This disclosure obligation shall be satisfi ed by providing to each purchaser a “Local Option Real Estate Transfer Disclosure St atement” specified by the Town and by providing a copy of this chapter.

F. If developed real property is to be sold which does not contain a solid fuel burning appliance, a form approved by the building di vision, containing t he notarized signatures of the seller, the buyer, and t he listing real estate agent attesting to the absence of any fuel device, may be accepted in lieu of an inspection. A written exemption shall be issued by the building division.

G. No appliance(s) removed under the prov isions of this section may be replaced except as provided by this chapter.

H. This section shall not be applicable to Nati onal Forest permittees located west of Old Mammoth Road in Sections 4 and 9 of Town ship 4 S., Range 27 E., MDBM, or National Forest permittees located above 8,500 feet elevation abov e sea level.8.30.060 - Opacity limits.

No person shall cause or permit emissions fr om a solid fuel burning appliance to be readily visible, for a period or periods aggr egating more than three minutes in any onehour period. Emissions created during a 15 minut e start-up period are exempt from this regulation. Readily visible emissions means smoke easily seen when viewed against any contrasting background including, but not limited to native conifers or a blue sky and may be equated with an opacity limit of 20 percent or gr eater as designated by the shade No. 1 on the Ringelmann Chart.

8.30.070 - Prohibited fuels.

Burning of any fuels or materials other than the following fuels within the town shall be in violation of this chapter:

A. Untreated wood;

B. Uncolored paper, including newspaper; and

C. Manufactured logs, pellets, and similar manufactured fuels.

8.30.080 - Mandatory curtailment.

A. The Town Manager shall appoint an ai r quality manager. The duty of the air quality manager shall be to determine when curtailment of solid fuel combustion in the town is necessary, notify the community that curta ilment is required, and make such other determinations as are necessary to carry out the objectives of this chapter.

B. Determination that curtailment is r equired shall be made when PM-10 levels have reached 130 micrograms/m3 or when adverse meteorological conditions are predicted to persist. Should it be determined that 130 micrograms/m3 is not a low enough threshold to prevent the Town from violat ing the National Ambient Air Quality Standard for 24 hours (NAAQS, 24 hours), that threshol d may be lowered by resolution of the Town Council.

C. Upon the determination that curtailment is required, the ai r quality manager shall contact all radio stations and television st ations in Mammoth Lakes and have them broadcast that it is required that there be no wood or other solid fuel burning. The air quality manager shall also record a notice on a telephone line dedicated to this purpose and post a notice in the Town offices. The air quality manager may utilize additional methods of communication to effectively in form Mammoth Lakes’ residents and visitors of burning restrictions. Upon such notice, a ll wood and other solid fuel combustion shall

cease.D. All dwelling units being rent ed on a transient basis which contain a solid fuel burning appliance shall post, in a conspicuous location near the appliance, a notice indicating that no-burn days may be called and informing the tenants about sources of information on no-burn days.

E. All persons renting units which contai n a solid fuel burning appliance shall inform their tenants that solid fuel burning may be prohibited on certain days and that the person signing the rental agree ment shall be responsible for assuring that the no-burn requirements are obeyed during the rental per iod identified on the rental agreement.

F. For residences where a solid fuel burning appliance is the sole means of heat, these curtailment regulations do not apply. For a residence to be considered as having solid fuel as its sole source of heat, the owner must apply to the building division for an exemption and the departm ent must inspect the residen ce and certify that no other adequate source of heat is available to the st ructure. Adequate source shall mean that the alternate source of heat cannot produce sufficient heat for the residence without causing a hazard. A written exempt ion will then be grant ed. Where an adequate alternate source of heat is determined to have been removed from the structure in violation of the building codes, a sole source exemption shall not be issued. Sole source exemptions shall not be grant ed for nonresidential uses.

G. Pellet fueled heaters shall not be subject to the provis ions of this section.

H. This section shall not apply to Nationa l Forest permittees located west of Old Mammoth Road, in Sections 4 and 9 of Township 4 S., Range 27 E., MDBM, or National Forest permittees located above 8,500 feet elevation above sea level.

8.30.090 - Pollution reducti on education programs.

The Town Manager or his/her designee is dire cted to undertake such public education programs as are reasonably calculated to reduce particulate air pollution within the town, including particulate emissions fr om sources other than solid fuel burning appliances. In addition to the notification me asures listed in Section 8.30.080.C, the public education programs sha ll include additional measures to inform the public of burning curtailment requirements.

8.30.100 - Road dust reduction measures.

A. The Public Works Director shall implem ent a vacuum street sweeping program to reduce PM-10 emissions resulting from exce ssive accumulations of cinders and dirt.

B. The Town shall, in its review of proposed development pr ojects, incorporate measures which reduce projected total v ehicle miles traveled. Examples of such measures include, but are not limited to, ci rculation system improv ements, mass transit facilities, private shuttles, and design and lo cation of facilities to encourage pedestrian circulation. The goal of the Town's review s hall be to limit peak vehicle miles traveled to179,708 on any given day on the roadway se gments evaluated in the Mammoth Lakes Vehicle Miles Traveled A nalysis (LSC, August, 2012).

8.30.110 - Fees.

A fee shall be charged for the inspection and permitting services of the Town. The fee shall be established in the To wn master fee schedule.

8.30.120 - Penalties.

A. It is illegal to violate any requirement s of this chapter. Any owner of any property which is in violation of the requirements of this chapter shall be guilty of an infraction. Any person operating a solid fuel burning appliance in violati on of this chapter is guilty of an infraction. The third violation by t he same person within a 12 month period shall constitute a misdemeanor. Prosecution of any violation of S ubsection 8.30.080.E, relating to exemptions from curtailmen t, may be against the property owner, the occupant, or both.

B. Violation of any portion of this chapter may result in assessment of civil penalties against the property and against an individual person or persons in accordance with Chapter 1.12, General Penalty.

C. Each and every day a violation exists is a new and separate violation. Right to appeal, hearings, and collection of civil penalties shall be pur suant to the procedures set forth in Chapter 8.20, Nuisances.

D. Nothing in this section shall prevent the Town from pursuing criminal penalties or using any other means legally available to it in addressing violations of this chapter.

E. Whenever necessary to make an inspection to enforce any of the provisions of this code, or whenever the air quality manager or his/her authorized representative has reasonable cause to believe that there exists in any building or upon any premises any condition which violates the provisions of this chapter, the air quality manager or authorized representative may ent er such building or premises at all reasonable times to inspect the same or to perform any duty imposed upon the air quality manager by this code; provided, that if such building or premises be o ccupied, he/she shall present proper credentials and request ent ry; and if such building or premises be unoccupied, he/she shall first make a reas onable effort to locate the owner or other persons having charge or control of the buildi ng or premises and request entry. If such entry is refused, or if the owner or person having charge or c ontrol of the building or premises cannot be contacted, the air quality m anager or authorized representativ e shall have recourse to every remedy provided by law to secure entry.M am moth Lakes AQMP



# Appendix D

VMT Estimates for Days of Air Quality Monitoring – 2003 to 2011

(LSC, 2013)M am moth Lakes AQMP



# Appendix E

Mammoth Lakes Vehicle Miles Traveled Analysis (LSC, 2012)

### TECHNICAL MEMORANDUM

DATE: August 3, 2012

TO: Ellen Clark, Town of Mammoth Lakes

FROM: Sara Hawley, PE and Leslie Suen, EIT, LSC Transportation Consultants, Inc.

SUBJECT: Mammoth Lakes Vehi cle Miles Traveled Analysis

As requested, LSC Transportation Consultants, Inc. has completed the analysis of Vehicle Miles Traveled (VMT) for the Town of Mammoth Lakes for use in the preparation of a Greenhouse Gas (GHG) inventory and an update to the 1990 Air Quality Management Plan. This memo presents the townwide VMT by roadway speed, as well as a limited analysis of VMT for external trips.

VMT by Travel Speed

Using the 2011 Town of Mammoth Lakes TransCAD Travel Model, VMT was calculated and grouped into speed classes based on the 85 th -percentile roadway speed, as shown in Table 1. VMT is calculated by multiplying the length of a roadway segment by the volume on that roadway. A map of the roadway speeds for all the roads in the model can be found in Appendix A, attached. Also shown in Appendix A are all the roadways included in the VMT analysis, which total approximately 240 roadways with 1,037 segments. The model reflect a typical winter Saturday, which will subsequently be called a ‘peak day’ throughout this report. Peak day conditions for both existing 2009 and future 2030 (reflecting build out of the general plan) scenarios were taken directly from the model. As indicated, a total of approximately 144,192 VMT are estimated to be generated in Mammoth over the course of an existing peak winter day, and approximately 179,708 VMT are estimated to be generated on a peak day in the future. This indicates a 25 percent increase by the time that buildout of the General Plan occurs (estimated at the year 2030).

In order to estimate annual average day conditions, peak day VMT was factored using Caltrans data along State Route (SR) 203. Specifically, daily traffic volumes at six locations on SR 203 within the Town of Mammoth Lakes were reviewed. As shown in Table 2, the percent decrease between peak month average daily traffic (Peak Month ADT) and annual average daily traffic (AADT) ranges from approximately 17 percent to 29 percent. The weighted average percent decrease is calculated to be about 23 percent. This reduction was applied to the model’s peak day VMT results, in order to estimate the VMT on an annual average day. As shown on the right side of Table 1, a total of approximately 111,287 VMT are estimated to be generated in TRANSPORTATION PLANNING AND TRAFFIC ENGINEERING CONSULTANTS

2690 Lake Forest Road, Suite C Post Office Box 5875 Tahoe City, California 96145 (530) 583-4053 • FAX: 583-5966 www.lsctahoe.com • info@lsctahoe.comMammoth Lakes VMT Page 2 August 3, 2012

Mammoth over the course of an existing annual average day, and approximately 138,698 VMT are estimated to be generated on an average day in the future.

In 1990 a similar VMT study was completed in combination with the Air Quality Management Plan for the Town of Mammoth Lakes (November 30, 1990). The methodology used in the 1990 study and this VMT study are similar. Both studies are based on a travel demand model that assumes full buildout of the Town’s General Plan in the future. Both studies include all of the Town’s major roadways. The main difference is the extent of the roadways analyzed in each study. The 1990 study had a total of 10.9 miles of roadways on 8 different roads (with 17 segments) for the existing year 1990 VMT, while the future year 2005 had a total of 15.8 miles of roadways on 10 different roads (with 31 segments). In contrast, this study’s VMT analysis included 93.1 miles of roadways on 420 different roads (with 1,037 segments) for both the existing and future analysis years. The higher number of miles of roadways included in this VMT analysis produces higher VMT estimates than the 1990 study. Additional comparison between the two studies can be found in the attached memo Mammoth Lakes Vehicle Miles Traveled Analysis – Comparison with 1990 Study (LSC, September 10, 2012).

External VMT

LSC reviewed information provided in the existing model at the two external points representing trips to/from Highway 395 - one on SR 203 east of Meridian Boulevard and one on Mammoth Scenic Loop north of town. Nearly all (approximately 97 percent) of the trips that enter and exit the model area use SR 203 to the east. A total of 8,880 vehicles are estimated to pass through the external points over the course of a peak day (total in both directions). Of the total number of trips generated in the Mammoth Lakes model area, about 15 percent are external trips, meaning they have either an origin or destination outside the model area. It should be noted that as the peak day of traffic activity is a winter Saturday , these figures do not reflect the many recreational trips occurring on a Friday or Sunday.

Trip Types

External trips can be broken down into the following five model trip types:

• home-based work

• home-based shopping

• home-based recreation

• home-based other

• other to other (example: work to shopping)

The large majority of the external trips (approximately 88 percent) are ho me-based recreation trips, such as a trip made by a person staying in Bishop and skiing in Mammoth Lakes, or staying in Mammoth and going elsewhere for recreation. The remaining 12 percent of trips are equally distributed among the other trip types, with approximately 3 percent of each trip type, as shown in Table 3.

Future external trips were also obtained from the model, and they are presented in Table 4. Again, the majority (85 percent) of the future external trips are generated by home-based recreation trips.

Residents vs VisitorsMammoth Lakes VMT Page 3 August 3, 2012

Trips going through the external points in the model were reviewed with respect to trips made by residents versus visitors. A precise breakdown cannot be provided based on available data. However, it is assumed that the majority of t he external trips on a peak winter day are made by visitors, given that most of the external trips are “home-based recreation” trips, which is a trip type primarily associated with visitors. It is also expected that the majority of home-based shopping trips are made by visitors. The remaining trip types (home-based work, home-based other, and other to other) are not assumed to be made by visitors.

Similarly, the split of residents versus visitors for internal trips cannot be provided based on available data. However, a general breakdown can be made based on the number of resident dwelling units and visitor dwelling units. In the TransCAD model, there are about 5,600 existing resident dwelling units and 5,000 visitor dwelling units (which include single-family vacation homes and lodging units). As the trip generation rate in the model is slightly higher for residential units, the total number of trips generated by residents is nearly equal to the total trips generated by visitors. Furthermore, the trip lengths for internal trips made by residents and visitors are assumed to be similar. Therefore, the resident/visitor split for VMT internal to Mammoth Lakes is estimated to be roughly a 50/50 split.

Residence Locations of Commuters

Data from the US Census 2010 indicates that more than half (approximately 57 percent) of persons who work in Mammoth Lakes also reside in Mammoth Lakes. About 12 percent of persons employed in Mammoth Lakes live in Bishop, California, with the remaining 31 percent residing in various locations throughout the Eastern Sierra. Of the workers commuting to Mammoth Lakes from external points, about 58 percent are estimated to reside in points to the north of Mammoth along US 395 and 42 percent are estimated to live to the south. Detailed percentages for each town in the Eastern Sierra are shown in Figure 1. Note the census data includes the Mammoth Yosemite Airport within the Mammoth Lakes analysis area.

Of all workers residing in Mammoth Lakes, almost all (approximately 96 percent) are employed in Mammoth Lakes. In other words, very few persons living in Mammoth Lakes leave the community to go to work.

Residence Locations of Visitors

The residence locations of visitors traveling to Mammoth Lakes from more remote destinations was reviewed, based upon data provided in the Town of Mammoth Lakes Winter Survey (Leisure Trends Group, 2007). Based on this survey, and shown in Figure 2 the home regions of all visitors to Mammoth include:

• Greater Los Angeles Area – 29%

• Outside California – 17%

• Orange County – 16%

• San Diego County – 14%

• Central Valley and Northern California – 13%

• Central Coast – 11%

The top home states for the 17 percent of visitors from outside California are Nevada, Maryland, Texas, Washington, Idaho, Arizona, Oregon and Utah (each state representing four percent or less of all visitors).Mammoth Lakes VMT Page 4 August 3, 2012

Trips to/from Mammoth Yosemite Airport

According to the 2007 Winter Survey, almost all respondents arrived via private automobile and no respondents reported flying to the Mammoth Yosemite Airport. This is unsurprising since commercial air service was not available at this time, but has since become available. Many hotels in Mammoth provide a free shuttle service to and from the airport in connection with flight times, and rental cars and taxi service are availabl e at the airport. While it is difficult to quantify exactly how many trips from various locations ma y have shifted from driving to flying since air service started, it is probable that at least a small portion of previous driving trips are now made by air. However, this shift is likely to be a ccompanied by a certain number of new airport-related trips including employee and passenger trips to and from Mammoth, and new visitors. Overall, the net change to VMT associated with airport-related trips is likely negligible relative to total daily trip volumes.

Estimate of Total External VMT

In order to determine the total VMT associated with activity in the Town of Mammoth Lakes, the VMT of the external part of the external trips (i.e. outside of the model area) needs to be considered. In VMT analyses for communities with high levels of visitor/tourism activity, some portion of the trip length that occurs outside the model area is typically allocated to the study community. For example, in recent VMT analyses conducted in Shasta County and in the Lake Tahoe area, 50 percent of the external VMT were allocated to the study area. For the purposes of this analysis, 100 percent of the external VMT is allocated to Mammoth Lakes.

To estimate the external VMT, the approximate mileage between Mammoth and each of theexternal locations shown in Figures 1 and 2 was estimated for each trip type. Of the homebased recreation trips, about 10 percent are assumed to be made to/from the Bishop area, reflecting that some visitors stay overnight at locations near Mammoth as a part of their trip, and that visitors staying in Mammoth will recreate in locations outside of the town itself. The remainder is allocated proportionately to the various points of visitor origin indicated in the 2007 survey. Multiplying the mileage by the number of external trips for each trip type yields the external VMT by trip type, as shown in Table 5.

Note all external VMT was calculated based on the TransCAD traffic model which estimates a busy winter Saturday, which when the highest traffic volumes occur in Mammoth Lakes but may not be when the peak external trips occur. A general estimation can be made of average annual daily VMT by reducing the peak VMT by 23 percent, which is the same percent internal VMT was reduced, as shown in Table 5.

Total Yearly VMT

Total VMT for one year is estimated based on the assumption that visitors’ home regions are similar in the summer and winter, as indicated in the Town of Mammoth Lakes Winter Survey (Leisure Trends Group, 2007) and Town of Mammoth Lakes Summer Survey (Leisure Trends Group, 2008). Adding the existing internal annual average VMT (111,287) to the external annual average VMT (1,730,000) yields a total of about 1,841,000 VMT per annual average day. Multiplying this total by 365 days per year yields about 672 million existing VMT per year. A similar calculation can be done for future VMT, which results in a total of about 705 million VMT per year in 2030.M am moth Lakes AQMP



# Appendix F

Mammoth Lakes Vehicle Miles Traveled Analysis Comparison with 1990 Study (LSC, 2012)

### TECHNICAL MEMORANDUM

DATE: September 10, 2012

TO: Ellen Clark, Town of Mammoth Lakes

FROM: Sara Hawley, PE and Leslie Suen, EIT, LSC Transportation Consultants, Inc.

SUBJECT: Mammoth Lakes Vehicle Miles Trav eled Analysis – Comparison with 1990 Study

As requested, LSC Transportation C onsultants, Inc. has completed an additional analysis of Vehicle Miles Traveled (VMT) for the Town of Mammoth Lakes to compare the 2012 VMT analysis to the previous 1990 Air Quality Management Plan (AQMP) VMT Study. First, the VMT on each roadway in the 1990 study was estimated, and the results are listed in Table A. As discussed in the 2012 VMT analysis memorandum, there are more miles of roadway included in the current TransCAD model than in the 1990 study. The VMT in the current TransCAD model was estimated for only those roadway segments included in the 1990 study. As show n in the right columns in Table A, a total of approximately 80,586 existing VMT and 110,641 futu re VMT are estimated on those roadways included in the 1990 study. Of the total existi ng VMT in the current TransCAD model network (144,192), about 56 percent are re flected on the roadways included in the 1990 study. Similarly, of the total future VMT in the current model ( 179,708), about 62 percent occur on roadways included on the 1990 study. The remaining VMT occurs on the smaller roads that were not included in the 1990 study. Note that these figur es are based on peak-day conditi ons, consistent with the 1990 study.

The following findings are made regarding the VM T on the roadways included in the 1990 Study:

• Overall, the VMT in Mamm oth Lakes has increased from approximately 66,275 in 1990 to approximately 80,856 in 2009. This equates to a total increase of approximately 22 percent over 19 years.

• In 1990, the future forecast indicated that the existing VMT would increase by more than double (approximately 222 percent) by 2005. Gi ven that the VMT in 2009 was only slightly higher than the VMT in 1990, this high rate of growth has not occurred.

• The future (2005) VMT forecasts made in 1990 are much higher than the future (2030) forecasts in the current TransCAD model, reflecti ng that the growth rate has decreased since 1990 and future development is expected to oc cur at a slower rate. Based on the current TransCAD model, VMT on the roadways included in the 1990 study is expected to increase by a total of 37 percent from 2009 to 2030. TRANSPORTATION PLANNING AND TRAFFIC ENGINEERING CONSULTANTS

2690 Lake Forest Road, Suite C Post Office Box 5875 Tahoe City, California 96145 (530) 583-4053 • FAX: 583-5966 www.lsctahoe.com • info@lsctahoe.comTable A: Vehicle Miles Traveled (VMT) ComparisonRoadwayFromToExisting(1990)Future(2005)Existing(2009)Future(2030)SR203/Main Street Meridian Blvd Minaret Road23,62527,79025,33128,373Lake Mary RoadMinaret Road Twin Lakes Parking Lot5,70011,2154,5264,952Meridian BlvdMajestic Pines Road Highway 2036,65025,15013,11517,967Old Mammoth Road Main StreetRanch Road11,900Old Mammoth Road1Ranch RoadRed Fir Rd-Sherwin Creek (OldMammoth Road Extension)2Old Mammoth Road South 0.1 miles-350 - -Forest TrailMain StreetMinaret Road1,5001,5001,4223,220Canyon BlvdLake Mary Road3Canyon Lodge Parking2,4004,9801,1755,982Lakeview BlvdCanyon Lodge Parking Canyon Blvd (East)5,0007,1003,4213,378Kelley/Majestic Pines4Lake Mary Road Meridian Blvd750 2,8001,1751,489Majestic Pines Extension Meridian Blvd Old Mammoth Road- 3,000--SR203/Minaret Road Main StreetScenic Loop Road8,75016,1609,608 10,878Minaret RoadMain StreetOld Mammoth Road- 26,2357,364 17,564Total 66,275 146,915 80,586 110,641Total VMT of all roadways included in the 2011 TransCAD Model144,192 179,708Portion of VMT included on the 1990 Study roadways56% 62%Note 1: The segment of Old Mammoth Road from Ranch Road to Red Fir Road did not exist in 1990.Note 2: The Old Mammoth Road Extension is not included in the TransCAD model.Note 3: In the 1990 VMT Study, Canyon Blvd is assumed to start at Minaret Road, consistent with its previous alignment.Note 4: The Majestic Pines Extension is not included in the TransCAD model.Source: LSC Transportation Consultants, Inc.20,635Estimated VMT in 1990Air Quality ManagementPlan Study2011 TransCAD ModelVMT16,83913,448M am moth Lakes AQMP



# Appendix G

Chemical Analysis of PM10 and PM2.5 Filters from Mammoth Lakes (DRI, 2013)1 

# Chemical Analysis of PM10 and PM2.5 filters from
Mammoth Lakes

Final Report

Prepared by:

Mark C. Green Division of Atmospheric Sciences

Desert Research Institute 2215 Raggio Parkway
Reno, NV 89512

Prepared for the Town of Mammoth Lakes
May 21, 20132 

### Chemical Analysis of PM10 and PM2.5 filters from Mammoth Lakes

Introduction

A study was conducted to try to gain understanding regarding s ource contributions to high PM10
values recorded at the Mammoth Lake s Gateway air quality monitoring site.

DRI proposed to analyze fifteen PM10 and five PM 2.5 filters (dates and concentrations shown in Tables 1 and 2) for elements and ions. The fi fteen PM10 filters included the nine highest and 11th highest PM10 filter concentration days sin ce 2001, eight of which were since the start of
2008. The other five PM10 filter s are days for which high PM 10 and/or PM2.5 concentrations were measured and both PM10 and PM2.5 filters are available for each day. Three of these five days had the highest PM10 for days with PM2.5 f ilters also. The other two days had high PM2.5 and high PM2.5 to PM10 ratios (indicative of la rge relative wood smoke impact). Because the road dust is expected to be mostly in the larger sizes and wood smoke is mostly in the small sizes (PM2.5) analyzing both PM10 a nd PM2.5 for a few days will be informative and will provide supporting evidence for our estimates based on the PM10 data.

The samples proposed to be an alyzed are listed below.

Table 1. Dates with only PM10 filters:

Date PM10 concentration 12/21/2001 134.2

2/13/2002 129.3

1/1/2008 85.9 2/9/2008 96.7 2/27/2008 95.5 2/21/2009 117.6

1/2/2010 101.3 1/29/2010 104.0 2/13/2010 92.0 1/12/2011 127.6

Table 2. Dates with PM10 and PM2.5 filters:

Date PM10 PM2.5 3/14/2001 55.0 35.2 12/17/2003 74.6 33.5

1/13/2005 39.3 27.0 1/19/2005 85.1 25.2 1/22/2005 77.8 27.43 Filters for the three days in 2001 and 2002 were not provided to DRI for analysis. Chemical analysis of filters was done on the remaining samples listed above, and included twelve PM10
filters and four PM2.5 filters.

The chemical analysis included X-ray fluorescence (XRF, giving most elements), ion chromatography (anion and cations), and light abso rption. The XRF analysis provides the road dust elements, ion chromatography the contributi ons from sulfate and nitrate, and ammonium (associated with nitrate and su lfate). The light absorption me asurement is a good indicator of elemental carbon (EC) (diesel exha ust and wood smoke primarily). What the analysis cannot do that is important is organic carbon (OC), because the Teflon filters that have been collected cannot provide that. Organic car bon was estimated as a residual.

Chemical analysis results

Total PM 10 concentrations and component concentra tions by date are shown in Table 3.

Table 3. PM10 concentrations and measured or reconstructed major species concentrations by
date. The residual is calculated as the tota l PM10 concentration – (soil+SO4+NO3+NH4+sea salt+ EC). It was assumed that all unaccounted for mass is organic mass (OM) and the ratio of organic mass to organic carbon is 1.8.

Date conc stp soil SO4 NO3 NH4 seasalt EC residual OC

12/17/03 74.6 22.3 0.32 0.64 0.02 0.30 9.1 41.9 23.3 01/13/05 39.3 5.5 0.28 0.40 0.02 0.07 10.2 22.8 12.7 01/19/05 85.1 34.1 0.33 0.49 0.02 0.25 9.0 40.9 22.7 01/22/05 77.8 28.9 0.27 0.40 0.00 0.28 8.3 39.7 22.0 01/01/08 85.9 44.3 0.60 0.69 0.03 0.37 9.8 30.2 16.8 02/09/08 96.7 25.2 0.30 0.38 0.02 0.20 6.8 63.8 35.4 02/27/08 95.5 44.6 0.40 0.38 0.05 0.11 7.5 42.5 23.6 02/21/09 117.6 51.6 0.79 0.80 0.05 1.12 7.6 55.6 30.9 01/02/10 101.3 44.6 0.29 0.48 0.00 2.68 7.6 45.6 25.4 01/29/10 104.0 47.3 0.36 0.54 0.04 0.68 6.7 48.4 26.9 02/13/10 92.0 41.2 1.10 0.50 0.23 0.34 7.9 40.7 22.6 01/12/11 127.6 4.3 0.16 0.16 0.00 0.07 5.4 117.4 65.2

Because only Teflon filters were available, OC and EC could not be analyzed. Reconstructed mass calculations (using the IMPR OVE protocol, Pitchford et al., 2007) showed that for most days, reconstructed mass was far less than measured mass. This is expected when there is a significant contribution from carbonaceous aero sol as with residential wood combustion, and other ambient sources of carbon, such as in road dust.

Elemental carbon was estimated from filter li ght absorption (Chow et al., 2010) as EC=(b abs )/10 where b abs is filter light absorption in inverse megameters (Mm -1 ) and EC concentration is in μg/m 3 . EC concentration was then added to the re constructed mass. The residual of measured4 mass – reconstructed mass was assumed to be organic mass (OM), which was assumed to be 1.8 times OC (as used in the IMPROVE algorith m). Thus OC is the residual/1.8.

From Table 3 it can be readily seen that OC, EC , and soil are the only si gnificant contributors to PM10 concentrations. The nitrate is expected to be biased low as it tends to volatilize off the filter, especially after exposure to x-rays in a va cuum as occurs during the XRF analysis prior to analyzing for nitrate with ion chromatography. It should be noted here that the PM10 concentration of 127.6 μg/m 3 on 1/12/2011 is probably in error. The soil and EC concentrations are not consistent with such a high mass con centration and the TEOM FDMS data for the day was only 27.7 μg/m 3 . The TEOM FDMS and filter PM10 were usually close in magnitude.

Table 4 shows the same information as Table 3 for the PM 2.5 samples.

Table 4. PM 2.5 concentrations and measured or recons tructed major species concentrations by date. To be comparable to the PM10 data, the c oncentrations have been adjusted to standard temperature and pressure as defi ned by EPA (25°C, 760mm Hg).

Date conc stp soil SO4 NO3 NH4 seasalt EC residual OC

12/17/03 40.6 1.19 0.24 0.45 0.03 0.12 7.8 30.8 17.1

1/13/05 32.7 0.50 0.24 0.39 0.03 0.04 10.2 21.4 11.9 1/19/05 30.5 1.89 0.26 0.28 0.03 0.07 8.8 19.2 10.7 1/22/05 33.2 1.60 0.21 0.29 0.02 0.08 8.3 22.7 12.6

For PM 2.5 , most of the mass is EC and residual (assume d OM). Table 5 shows the percentage of each chemical component that was in the fine mode (PM 2.5 ) for the four days with both PM 10 and
PM 2.5 chemically speciated data.

Table 5. Percent of each chemical co mponent that is in the fine mode.

PM10 stp soil SO4 NO3 NH4 seasalt EC OC 12/17/03 54.4 5.3 76.4 70.3 144.8 40.1 85.1 73.4

1/13/05 83.2 9.0 86.9 97.8 158.6 60.0 99.8 93.5 1/19/05 35.9 5.5 78.1 57.5 133.1 29.3 97.9 46.9 1/22/05 42.7 5.5 75.1 70.8 27.4 100.7 57.1

As expected most of the sulfate, nitrate, and EC are in the fine m ode and most of the soil is in the
coarse mode. For 12/17/03 and 1/13/05 most of the OC is in the fine mode as would be expected with wood smoke. For 1/19/05 and 1/22/05 only about half to a little more than half of the
estimated OC is in the fine mode. It should be noted that the fine/coars e mode OC split is highly
uncertain because OC in both size ra nges was estimated from a residual.

Diurnal patterns in PM10 concentrations

Consideration of di urnal patterns in PM 10 concentrations may provide insight into likely sources of high PM10. Hourly PM10 concentrations fo r chemical analysis days in 2009 and 2010 areshown i n which gi v had mor n

Figure 1

. 2/21/20 0

Table 6. days bef o

Date 12/17/2

1/13/2 1/19/2 1/22/2 2/21/2

1/2/2 1/29/2 2/13/2 1/12/2

Figure 2

measure m which d r n Figure 1. T

v es values s i

n ing and ev e

. TEOM F D
9.

Compariso n

o re 2009 a s t

Filter
0 03 7 4
005 3 9
005 8 5
005 7 7
009 11 7
01 0 10 1
01 0 1
01 0
011 12 7

gives hourl y

m ents. Thes e

r ives off mo s T his period h
i milar to th e

e ning peaks a

D MS hourly c

n of filter P M

t andard TE O

TEOM
4

. 6 60. 4
9 .3 29.
5 .1 4
7 .8 40.
7 .6 116.
1 .3 97.
0 4 107.
92 8
7 .6 26.

y PM10 con c

e were meas

s t of the vol a h ad hourly m

e filter base d

a lthough th e

c oncentrati o

M 10 and TE
O M was use d

TEOM/Fil t
4 0
2 0
6 0
1 0
2 0
3 0
6 1
7 0
8 0

c entrations f ured using a

a tile compo u

5 m easuremen t d concentrati o

e timing of t h

o ns for 1/2/2

O M PM10 f
d . From 20 0

t er 0 .81
0 .7 4
0 .5 4
0 .52
0 .99
0 .9 6
1 .03
0 .95
0 .21

f

or days in 2

a standard T E

u nds includi n t s using the T

on measure m h e peaks va r

010, 1/29/2 0

f

or days wit h
0 9 and after,

2 003 and 20 0

E OM whic h

n g much of t T EOM FD M

m ents (Tabl e

r ied.

0 10,2/13/20 1

h chemical s

, a TEOM F D

0 5 with che m h heats the s a

t he organic m M S monitor

e 6). All da y

1 0 and

s peciation. F
D MS was u s

m ical specia t

a mple to 50 °

m aterial in w y s

or

s ed.

t ion

° C

w oo dsmoke a n filter- b a s

Figure 2

. Figure 3
and Feb r frame w i

concentr a period s h expecte d peaks ar e traffic re l
however
levels h a the stan d peak in P 2009-20 1 sample. T late eve n n d ammoni u

s ed PM10 a s

. TEOM ho u

shows aver a

r uary) for th e i th standard T

a tions are si m h ows some w d because th e

e of very si m l ated (e.g. r o that volatil e ve decrease d
d ard TEOM,
P M10 seen g 1 2 period sh
T his sugges t

n ing to morn i u m nitrate. D

shown in T

u rly PM10 c

a ge TEOM P

e 2001-2008
T EOM (20 0

m ilar and di u

w hat higher c

e standard T E

m ilar concen t

o ad dust) an d

e compoun d s d by an amo
thus maski n
g ives the sa m

ows higher v
t s that the in f
i ng and that D uring these

able 6.

c oncentratio n

P M10 by ho u and 2009- 2
0 1-2008) an d

u rnal patter n

c oncentratio n E OM volati l

t ration both
d that conce n

s (e.g. wood

u nt equal to

n g any trend

m e concentr a

v alues likel y f luence of w the earlier r

6 days, the T E

n s for 12/17 /

u r of day fo r 012 periods
d the period w

n s both sho w

n s overnight
l izes a porti o periods, su g

n trations ha v

smoke) als o the volatile
in time. W e

a tions for bo t
y due to less

w ood smoke r

ise in PM1 0 E OM PM1 0

/ 2003, 1/19 /

r winter mo n . This essen t

w ith TEO M

w morning a n

(from abou t

o n of the wo

g gesting that

v e changed l

o contribute

component

e can also n o
t h time peri o volatilizati o relative to r o 0 may be dri v 0 was much l

/ 2005, and 1 /

n ths (Dece m
t ially co r res p M FDMS (20 0

n d evening p
t 9pm to 8 a m

o od smoke. T

this peak is
l ittle over ti m to the morn i
of the woo d

o te that the e

o ds until aft e

o n of wood s

o ad dust inc r

v en mainly b l ess than the

/ 22/2005.

m

ber, Januar y
p onds to th e 0 9-2012). T h

p eaks. The l

m ). This is
T he mornin g

almost enti r

m e. It is po s i ng peak an d
d smoke lost

arlier eveni n

e r 9pm whe n

s moke from

r eases durin
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e time
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r ely

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.Figure 3

. for the 2 0 2008 pe r

Method o

Chemic a PM10 a n 1990 Ai r of the P M the curre changed

Source p

P

M10 a n
Source p fireplace significa n uncertai n again no t improve d profiles, part woo profile. . Average P
0 01-2008 a n

r iod mostly w

o lo gy for C M

a l mass bala n

n d PM2.5 fo r

r Quality M a M 10 was du e

nt study is t o since the19 9

rofiles used f

n al y sis

rofiles were
s were used

n t collineari t

n ty to wood s
t using the w d results. It but the qual d stove pro f M 10 b y hou r

n d 2009-201 2

w as standar d

M B 8 runs f

n ce (CMB) v

r days with c

a nagement P

e to road du s

o try to dete r 9 0 report.

f

or CMB

taken from plus road d u
t y occu r red b

s tove contri b

w ood stove s

was attemp t i ty of the re s f ile was also r of day for w 2 periods. T h
d TEOM.

f

or Mamm o

v ersion 8 (U S

c hemically s lan (AQMP

s t and reside n

r mine if the

the 1990 A Q

u st and cind e b etween the
b utions (so m ource, just fi

t ed to impro v

s ults deterio r tried and re s

7 w inter mont h
h e 2009-20 1

o th Lakes P

S EPA) was

s peciated da t , Ono et al, 1

n tial wood c relative con t

Q MP. Profi l

e rs. When r u

wood stov e

m etimes sig n fi replaces, ci n

v e results b y

r ated. A w e

s ults were n o h s (Decemb e 1 2 period ha

M10 and P M

used to esti m
t a. CMB an a 1990) for M

c ombustion (
tribution of

l es for Ma m

u nning CM B

e and firepla c

n ificantly n e nders, and r o
y averaging t

e ighted aver a

ot as good a er, January,

a d TEOM F D

M 2.5

m ate source

a lysis done i n M ammoth La k

( RWC). On e RWC and r o

m moth Lakes

B it was fou n

c e sources, g

e gative). C M

o ad dust. T h

t he wood st o

a ge of 3 par t

a s simply us i and Februa r D MS; the 20

contributio n

n support o f
k es showed m

e of the goal

o ad dust has

woodstove s

n d that

g iving high
M B was run
h is gave mu

o ve and fire p
t s fireplace t
i ng the firep l r y)
0 01-

n s to f the

m ost s of

s and

ch

p lace
o 1
l ace8 PM2.5 analysis

The PM2.5 analysis had collinearity problems between wood stove and fireplace and between road dust and cinders. The analys is with the best results used fireplaces and road dust source profiles only.

Fitting species

CMB results can vary significantly based on the c hoice of fitting species selected. In the initial run, all species measured with available source an alysis were used. This gave poor results. Species that were noted from the ambient data to represent the mix of sources were added and
subtracted in a trial and error method until the best results were obtained. Attention was paid to squared correlation coefficient, the Chi squa re statistic and percent of mass explained performance measures (Watson, 2004). The fittin g species included: soluble Cl, ammonium, soluble K, total K, Na, Al, Si, S, Ca, Ti, Fe, EC, OC, Ba, Sr, and Zn.9 CMB results

Results for the best fitting CMB analysis ar e shown in Table 7. Recommended performance measures (Watson, 2004) are % mass accounted for 100±20%, R-squared>0.80, and Chi-squared < 4.0. For the PM10 results (discounting the 1/12/2010 sample), 10/11 cases have % mass 100±20%, all cases have R-squared>0.80, and 5/11 m eet the Chi-squared <4.0 criteria. For the PM2.5 results, three out of four met the mass cr iteria and all four met the R-squared and chisquared criteria.

Table 7. CMB attribution result s and performan ce statistics.

DATE SIZE conc stp FP RD CIND SUM % mass R 2 Chi 2 12/17/03 10 74.6 53.0 9.6 10.2 72.8 97.5 0.94 3.70 01/13/05 10 39.3 31.1 3.6 1.7 36.5 92.7 0.92 3.76 01/19/05 10 85.1 51.8 18.1 11.5 81.3 95.5 0.93 4.39 01/22/05 10 77.8 47.5 16.9 8.7 73.0 93.8 0.94 3.70 01/01/08 10 85.9 53.4 24.6 14.8 92.9 108.1 0.93 4.73 02/09/08 10 96.7 68.0 10.2 13.8 92.0 95.1 0.94 3.35 02/27/08 10 95.5 52.6 26.1 12.7 91.3 95.6 0.90 6.40 02/21/09 10 117.6 91.7 26.6 21.0 139.3 118.5 0.94 3.89 01/02/10 10 101.3 100.4 23.2 19.0 142.6 140.8 0.90 6.88 01/29/10 10 104.0 65.8 24.5 16.8 107.1 103.0 0.93 4.52 02/13/10 10 92.0 68.9 25.9 13.9 108.7 118.2 0.91 6.09 01/12/11 10 127.6 43.9 2.2 1.8 47.9 37.5 0.82 8.77 12/17/03 2.5 40.6 28.6 1.5 30.0 74.0 0.96 0.90 01/13/05 2.5 32.7 27.5 0.6 28.1 86.0 0.81 3.90 01/19/05 2.5 30.5 28.1 2.2 30.3 99.3 0.89 2.73 01/22/05 2.5 33.2 27.6 1.9 29.5 89.0 0.92 2.00

The percent of each sample attributed to each source is shown in table 8. On average, residential
wood combustion contributed a bout 2/3 of the PM10, while tr affic (road dust + cinders) contributed about 1/3, acco rding to the CMB results.10 Table 8. Percent of each sample attributed to fireplaces, road dust, and cinders. January 12,
2011 not included as this date ha d an apparent mass problem as discussed earlier. January 13,
20o5 was not included in the PM10 list because it had low PM10 concentrations and thus does not represent a high PM10 day.

DATE SIZE conc stp FP% RD% CIND% 12/17/03 10 74.6 72.9 13.2 14.0 01/19/05 10 85.1 85.3 10.0 4.7 01/22/05 10 77.8 63.7 22.2 14.1 01/01/08 10 85.9 65.0 23.1 11.8 02/09/08 10 96.7 57.5 26.5 16.0 02/27/08 10 95.5 73.9 11.1 15.0 02/21/09 10 117.6 57.5 28.5 13.9 01/02/10 10 101.3 65.8 19.1 15.1 01/29/10 10 104.0 70.4 16.3 13.3 02/13/10 10 92.0 61.4 22.9 15.7 12/17/03 2.5 40.6 28.6 4.5 01/13/05 2.5 32.7 95.2 4.8 01/19/05 2.5 30.5 97.7 2.3 01/22/05 2.5 33.2 92.6 7.4

Average PM10 93.1 67.4 19.3 13.4 Average PM2.5 34.3 78.5 4.7

For the winter 1987-1988 study (Ono et al, 1990), on average, fireplaces c ontributed 75% of the PM10 and road dust 25%. Table 9 compares the results of the 1987-88 study to this study. Three of the days in the 1987-88 study showed wood smoke contributing >95% of the PM10; the current study shows no high PM10 days with great er than 75% of the PM10 contributed from
wood smoke.

Furthermore, the peak contributions of road dust and residential wood combustion to PM10 appear to have diminished. For the 1987-88 stu dy average contributions to PM10 from road dust and fireplaces for the three highest impact days were 72 and 107 μg/m 3 , respectively. For the 2008-2010 period these fell to 56 and 72 μg/m 3 . This represents a 32% drop in road dust concentrations and 33% drop in residential wood combustion concentrations on high impact days.11 Table 9. CMB percent contributions to PM 10 by road dust (RD) and residential wood combustion (RWC) for the winter 1987-88 study and this study (2003-2011). Road dust and
cinders contributions are combined into RD .

Date Conc RD% RWC% 12/26/1987 125.9 2.3 97.7 12/30/1987 132.8 1.3 98.7 12/31/1987 142.8 2.5 97.5 1/1/1988 117.4 10.3 89.7 1/22/1988 143.8 33.7 66.3 1/23/1988 157.8 41.2 58.8

2/3/1988 104.3 31.5 68.5 2/5/1988 148.2 33.8 66.2 2/6/1988 160 31.2 68.8 2/13/1988 137.6 38.8 61.2 2/14/1988 144 45.2 54.8 2/19/1988 148.5 28.7 71.3

12/17/03 74.6 25.3 74.7 01/19/05 85.1 33.7 66.3 01/22/05 77.8 32.5 67.5 01/01/08 85.9 39.5 60.5 02/09/08 96.7 24.3 75.7 02/27/08 95.5 39.4 60.6 02/21/09 117.6 32.0 68.0 01/02/10 101.3 27.7 72.3 01/29/10 104.0 36.0 64.0 02/13/10 92.0 33.8 66.2

1987

‐ 88 study average 25.0 75.0 This study average 32.4 67.6

A simple alternative method for estimating source attributions

Another estimate of crustal type sources (road dust and cinders) as percent of total PM was made by computing reconstructed fine soil (IMPROVE equation) and adding estimated associated carbonaceous aerosol mass (EC + 1.8*OC). Cinders have essentially no carbon, but road dust is about 10% OC and about 1% EC. As an uppe r limit it was assumed that OC and EC are proportional to the reconstructed so il at the same ratio as in road dust and this is added to the reconstructed soil calculation. The results (Tab le 10) show a higher average contribution from road dust and cinders (about 49%) than the CM B analysis (about 35%). Note: this method assumes organic and elemental carbon at the same abundance as in road dust and may be expected be an overestimate of carbon in road dust + cinders as cinders have essentially no carbon. It may thus represent an upper limit to the road dust and cinde r contribution to PM10.12 Table 10. Comparison of contribution of crustal elements from mass reconstruction calculations (soil+rd C) and CMB analysis (rd+cind).

date soil+rd C % rd+cind % 12/17/03 35.9 27.1 01/19/05 48.2 36.3 01/22/05 44.7 35.0 01/01/08 62.0 42.5 02/09/08 31.3 26.1 02/27/08 56.2 42.5 02/21/09 52.8 34.2 01/02/10 52.9 29.6 01/29/10 54.7 38.6 02/13/10 53.9 36.6

average 49.3 34.8

Analysis of days with both PM10 and PM2.5 speciated data

Four days have both PM10 and PM2.5 speciated data. For these days, by subtraction of the
PM2.5 attribution from the PM10 attribution we can get a value for PM coarse (PM10-PM2.5)
attribution. These results are shown in Table 11.

Table 11. CMB attribution (μg/m 3 ) to wood smoke (FP) and road dust (rd+cind) by size fraction for four days with chemically speciated PM2.5 and PM10.

DATE SIZE stp conc FP rd+cind

12/17/03 10 74.6 53.0 19.7 12/17/03 2.5 40.6 28.6 1.5 12/17/03 coarse 34.0 24.5 18.3

1/13/05 10 39.3 31.1 5.4 1/13/05 2.5 32.7 27.5 0.6 1/13/05 coarse 6.6 3.6 4.7 1/19/05 10 85.1 51.8 29.5 1/19/05 2.5 30.5 28.1 2.2 1/19/05 coarse 54.6 23.7 27.3 1/22/05 10 77.8 47.5 25.5 1/22/05 2.5 33.2 27.6 1.9 1/22/05 coarse 44.6 19.8 23.6

average 10 69.2 45.8 20.0
2.5 34.3 27.9 1.6
coarse 34.9 17.9 18.513 Table 11 shows that over 90% of the PM10 mass at tributed to road dust and cinders is in the coarse mode, as would be expected. However, on average for these days only a little more than 60% of the wood smoke (FP) is attribute to the fi ne mode, with about 40% in the coarse mode. This is somewhat unexpected, as a large majority of wood smoke is expected to be in the fine mode. The result is also contrary to the 1987-88 study which found the vast majority of the wood smoke impact in the fine mode. The attribut ion in the current study wa s largely a result of having a large residual in the reconstructed mass due to the inability to measure carbon on Teflon filters. The main question regards the “missing ma ss” which was assumed to be organic mass. If it is organic mass then what is it from if not wo od smoke? Some would be associated with road dust, but not the levels needed. Some also woul d be from motor vehicles, but again this would almost all be expected to be in the fine mode. It is possible the reconstruc ted soil equation used is not appropriate for the local conditions and this would affect the residual used to estimate organic carbon. There could also be some water accounting for the missing mass, but concentration of hygroscopic compounds such as sulfate and nitrate are low and mainly in the fine mode, so this would not be expected to account for much. Because the wood smoke is present along with road dust, the road dust may become coated with wood smoke, thus causing a significant fraction of the wood sm oke associated organic mass to be in the coarse mode.

Summary and conclusions

The question of the relative c ontributions of wood smoke and road dust to PM10 in Mammoth
Lakes was considered. Teflon filters fr om high PM10 days between 2003 and 2011 were subjected to chemical analysis with XRF, ion chromatography, and filter light absorption. Four days analyzed also had PM2.5 filters that under went chemical analysis. A major limitation was the inability to measure carbon on the filters. The filter light absorption provided a reasonable estimate of elemental carbon and the unexplaine d mass (on average 58% of PM10 and 68% of PM2.5) was assumed to be organic mass (OC*1.8) . Estimates of contribution of wood smoke and road dust were made using Chemical ma ss balance (CMB) and a simple method based on abundance of crustal elements in the samples. For PM10 CMB showed an average of 32% due to road dust and 68% due to resi dential wood combustion. This compares to 25% from road dust and 75% from residential wood combustion for the winter 1987-88 study. The CMB maximum contributions (average of 3 highest days) to PM10 from road dust and residential wood combustion dropped by about 1/3 for each so urce category between 1987-1988 and 2008-2010.

A simpler method using reconstructed soil from the IMPROVE equation and adding organic
mass and elemental carbon in the ratio found in Ma mmoth Lakes road dust gave an average of 49% contribution of road dust to PM10. There is likely some impact from other sources such as
vehicle exhaust to the PM10 alt hough these impacts are expected to be small in comparison to
wood smoke and road dust. The relative contri bution of wood smoke may have decreased since the 1990 AQMP was produced. The extent of any such decrease cannot be reliably determined
with the data available. Additi onal measurements, chemical analys is and data analysis would be necessary to gain more confidence in the results.14 References

Chow, J.C.; Watson, J. G.; Green, M. C.; Fra nk, N.H. (2010). Filter light attenuation as a surrogate for elemental carbon. J. of Air & Waste Mgmt. Assoc. ,60 1365-1375. Ono, D.; Taylor, W., Lawhon, D. (1990). Air Qu ality Management Plan for the Town of Mammoth Lakes. November 30, 1990. http://www.gbuapcd.org/mlaqmp.htm . Accessed May 2013.

Pitchford, M.L.; Malm, W.C.; Schichtel, B.A.; Kumar, N.K.; Lowenthal, D.H.; Hand, J.L. (2007). Revised algorithm for estimating li ght extinction from IMPROVE particle speciation data. J. Air Waste Manage. Assoc.

, 57 (11):1326-1336.

Watson, J. G. et al. (2004). Protocol for A pplying and Validating the CMB Model for PM2.5 and VOC. EPA-451/R-04-001, December 2004. Prepared for USEPA Office of Air Quality Planning and Standards. http://www.epa.gov/scram001/mode ls/receptor/CMB_Protocol.pdf . Accessed May 2013.