Kings River Experimental Watershed Project 1 November, 2010 

Sierra National Forest

High Sierra Ranger District

AIR QUALITY SPECIALIST REPORT 

KINGS RIVER EXPERIMENTAL WATERSHED PROJECT

P R E P A R E D B Y :

Carolyn Ballard

District Prescribed Fire and Fuels Specialist

High Sierra Ranger District

Sierra National Forest

November 2010
Kings River Experimental Watershed Project 2 November, 2010 

Sierra National Forest

High Sierra Ranger District

Abstract

This report analyzes the effects of the Alternatives proposed to meet the purpose and need 

for the Kings River Experimental Watershed Forest Health and Research Project (KREW, or 

the Project) to air quality and visibility. The federal Clean Air Act as amended in 1990

(CAAA) requires that any federal action will determine that actions conformity to State 

Implementation Plans (SIPs). Total direct and indirect emissions were calculated for the 

management actions proposed by each alternative. These were compared to the federal de 

minimus levels for criteria pollutants where the San Joaquin Valley is in nonattainment 

and/or in a maintenance level. Two pollutants would be over de minimus levels (NOx and 

VOC, precursors to ozone), but when compared to annual average daily emissions for the 

San Joaquin Valley air basin were less than 10% of that emitted regionally, thus the project 

management actions are expected to conform with the State Implementation Plan. The 

direct, indirect and cumulative effects for the Alternatives proposed by KREW are expected 

to be of short duration and generally small in scale. These include the effects from 

prescribed burning (typically conducted during the late fall, winter and spring months), 

mechanical treatments (typically conducted during the summer months) and wildfire. 
Kings River Experimental Watershed Project 3 November, 2010 

Sierra National Forest

High Sierra Ranger District

INTRODUCTION

Fire is an important part of California ecosystems, but it also produces combustion byproducts that are potentially harmful to human health and welfare. Carbon dioxide (CO2)

and water are the two products of complete combustion and generally make up 90 percent 

of the total emissions from wildfire. In incomplete combustion that occurs under wildfire 

conditions, smoke is composed of carbon dioxide, water vapor, carbon monoxide (CO), 

particulate matter, hydrocarbons, and other volatile organic compounds (VOCs), nitrogen 

oxides (NOx), trace minerals and several thousand other compounds. Particulate matter is 

the principle pollutant of concern to human health from wildfire smoke for the short-term 

exposures typically experienced by firefighters and the public. Studies indicate that 90 

percent of smoke particles emitted during wildland burning are particles that measure less 

than ten microns in size (PM10), and about 90 percent of these are less than 2.5 microns in 

size (PM2.5). Hydrocarbons and nitrogen oxides from large wildfires contribute to increased 

ozone formation (which causes injury to plants) under certain conditions (Ahuja 2006). 

There are two general strategies to managing wildfire smoke: (1) emission reduction and (2) 

emission redistribution. All pollutants except nitrous oxide are negatively correlated with 

combustion efficiency, so actions that reduce one pollutant result in the reduction of all. 

Emission redistribution techniques may effectively keep smoke impacts away from sensitive 

areas, but does little to reduce the amount of emissions produced. But optimal use of 

reduction techniques can reduce emissions by approximately 20 to 25 percent, assuming all 

other factors (vegetation types, acres, etc.) were held constant and land management goals 

were still met. Emission reduction techniques can include reducing the area burned, 

reducing fuel loading, reducing fuel production, reducing fuel consumption, and scheduling 

burning before new fuel appears and increasing combustion efficiency (Ahuja 2006). These 

reduction techniques, which can include prescribed fire, mechanical harvesting (which 

includes road work, cutting, and hauling of material) and vegetation management treatments 

(mastication and mechanical piling) can produce emissions that can affect human health 

and visibility.

The purpose and need of this project is to treat the Providence and Bull units of the Kings 

River Experimental Watershed to improve forest health and exam the short and long term 

effects of these treatments. This report analyzes the direct, indirect and cumulative effects to 

Air Quality and visibility from the alternatives proposed to meet this purpose and need as 

well determines the General Conformity of these actions to the Clean Air Act.

AFFECTED ENVIRONMENT

The KREW project is within the San Joaquin Valley air basin and is regulated by the San 

Joaquin Valley Unified Air Pollution Control District (SJVAPCD). The SJVAPCD is 

responsible for implementing and regulating sources that degrade air quality and are 

responsible for meeting Federal and State air quality standards. The California Air 

Resources Board (CARB) has oversight authority to monitor performance.
Kings River Experimental Watershed Project 4 November, 2010 

Sierra National Forest

High Sierra Ranger District

The affected environment (geographic scale) in this analysis includes areas that would or 

could experience degradation of air resources as a result of the proposed actions. The San 

Joaquin Valley is considered the air basin downwind of the project and is the area the direct, 

indirect and cumulative impact analysis is focused on.

The dispersion of pollutants is affected by local meteorological conditions. Pollutants can 

stay trapped in one place if there is no mixing caused by wind and temperatures. Prescribed 

burns are conducted on days when atmospheric ventilation transports smoke and pollutants 

away from the San Joaquin Valley and pollutants are not normally a problem. Burns are 

conducted on authorized burn days only in consultation with the SJVAPCD. Poor ventilation 

occurs during summer and fall months when the valley is characterized by relatively stable 

air masses. Ozone concentrations can reach peak levels when strong sunshine and 

temperatures above 95 degrees F accompany periods of poor ventilation. Although ozone is 

not released directly to the atmosphere, it is produced by chemical reactions involving Visual 

organic compounds (VOCs) and nitrous oxides (NOx). The meteorological factors favorable 

to significant ozone formation occur only during the summer. 

The Fresno Metropolitan area, the communities of Shaver Lake, Auberry, Tollhouse, and 

Providence including Class I Airsheds, schools airports and recreation sites are considered 

smoke sensitive receptors where smoke and air pollutants can adversely affect public 

health, safety and welfare. These areas could be affected by smoke if weather patterns 

produce a stable air mass and smoke is unable to vent into the upper atmosphere. Since 

PM10, PM2.5 and ozone are public health hazards, prescribed burns would be planned 

during periods of unstable air, which would allow for proper ventilation and temperatures 

less than 95 degrees. However, since prescribed underburns could last for several days or 

weeks there is the potential for recurring shifts in air masses toward more stable conditions. 

For this reason, all prescribed fire activities are coordinated with SJVAPCD and would be 

implemented under optimum conditions using best available control measures (listed in

Chapter 2 under Air Quality [Fuels]) to prevent smoke concentrations from affecting local 

communities. Sensitive receptors were considered within 100 kilometers (10 miles) of the 

project area and are listed in Table 1 below.
Kings River Experimental Watershed Project 5 November, 2010 

Sierra National Forest

High Sierra Ranger District

Table 1. Sensitive receptors identified within 10 miles of KREW.

Sensitive 

Receptor 

Type

Location

Towns, 

Communities

Exchequer, Shaver Lake, Petersen Mill, Cressman Road, 

Wishon

Recreation 

Areas

Dinkey Creek Recreation Area, Wishon Reservoir, Shaver 

Lake Recreation Area. 

Campgrounds Dinkey Creek, Sawmill Flat, Bretz Mill, Dorabella, Swanson 

Meadow, Camp Edison, Camp Fresno.

FS Work 

Center/Ranger

Station

Dinkey Creek Ranger Station, Glen Meadow Work Center, 

Dinkey Creek Work Center, Wishon Work Center, Blue 

Canyon Work Center, Mountain Rest Station.

Roads State Highway 168, Forest Service and County Roads

Class I 

Federal areas

See Table 2 for Class I areas

Other Private lands within and adjacent to the project area

Regulatory Setting (Applicable Laws, Policies, and Regulations)

The Sierra National Forest Land and Resource Management Plan (SNF LRMP) as 

amended provides the standards and guidelines for the proposed action. It states that 

“Forest activities will be managed so air quality is compatible with federal, state and local 

laws; including a program that achieves the Clean Air Act responsibilities” (SNF LRMP 1992, 

pg. 4-2). The SNF LRMP has Standards and Guidelines for Air Quality (SNF LRMP 1992, 

pgs. 4-25) that include the following:

 Avoid cumulative impacts to air quality by coordinating prescribed burning activities 

within the Forest, with burning activities conducted by others (SNF LRMP 1992 S&G # 

216).

 Mitigate fugitive dust impacts on air quality by including dust abatement as a 

requirement for construction activities that have potential to generate dust (SNF LRMP 

1992 S&G # 217).

 Avoid prolonged effects from prescribed burning activities on air quality by burning only 

on Air Quality Control Board (AQCB) approved burn days when satisfactory wind 

dispersion conditions prevail (SNF LRMP 1992 S&G # 218).

 Participate with Air Quality Control Board (AQCB) to qualitatively define air quality 

control regulations and guidelines and effects of air quality on the Forest, from sources 

outside the Forest (SNF LRMP 1992 S&G # 219).

 Obtain appropriate permits prior to conducting prescribed burning activities (SNF LRMP 

1992 S&G # 220).
Kings River Experimental Watershed Project 6 November, 2010 

Sierra National Forest

High Sierra Ranger District

 Incorporate air quality management considerations into fire management (SNF LRMP 

1992 S&G # 230).

Federal Conformity Requirements

The CAAA require that all projects receiving federal funds must conform to the appropriate 

SIP. Federal actions are subject to either the Transportation Conformity Rule (40 CFR 

51[T]), which applies to federal highway or transit projects, or the General Conformity Rule 

(40 CFR 51[W]), which applies to all other federal actions. Because the Sugar Pine Adaptive 

Management Project is not a federal highway or transit project, it is subject to the General 

Conformity Rule.

General Conformity Rule Requirements

The purpose of the General Conformity Rule is to ensure that federal actions conform to 

applicable SIPs so that they do not interfere with strategies employed to attain the National 

Ambient Air Quality Standards (NAAQS). The rule applies to federal actions in areas 

designated as nonattainment, or in some cases maintenance, for any of the six criteria 

pollutants. The rule applies to all federal actions except:

Programs specifically included in a transportation plan or program that is found to 

conform under the federal transportation conformity rule.

Projects with associated emissions below specified de minimus threshold levels.

Certain other projects that are exempt or presumed to conform.

A general conformity determination would be required if a proposed federal action’s total 

direct and indirect emissions fail to meet one of these two conditions:

Emissions for each affected pollutant for which the region is classified as a 

maintenance or nonattainment area for the NAAQS are below the de minimus levels 

indicated in Table 2.

Emissions for each affected pollutant for which the region is classified as a 

maintenance or nonattainment area for the NAAQS are regionally insignificant (total 

emissions are less than 10% of the area’s total emissions inventory for that 

pollutant).

If either of these conditions is met, the requirements for general conformity do not apply 

because the proposed action is presumed to conform to the applicable SIP for each affected 

pollutant. As a result, no further analysis or determination would be required. If neither of 

these conditions is met, a general conformity determination must be performed to 

demonstrate that total direct and indirect emissions for each affected pollutant for which the 

region is classified as a maintenance or nonattainment area for the national standards would 

conform to the applicable SIP.

The Project is located entirely within the SJVAPCD. Currently, the valley is classified by both 

the federal and state standards as severe non-attainment for ground-level ozone and as 
Kings River Experimental Watershed Project 7 November, 2010 

Sierra National Forest

High Sierra Ranger District

maintenance status for PM10. The valley is designated as in attainment for all other criteria 

pollutants. (www.valleyair.org)

The EPA, for determining conformity, has developed de minimus (levels that are so small 

that the law does not take it into consideration) levels for each of the criteria pollutants 

based on an air basins attainment status for each pollutant. The table below shows these 

de minimus level thresholds and are bolded based on air basin status. 

Table 2. Federal de minimus Threshold Levels for Criteria Pollutants based on Air Basin 

attainment status. 

Pollutant Area Type Tons/Year

Ozone (NOx or 

VOC)

Severe nonattainment (SJV Air Basin) 25

Carbon monoxide, 

SO2 and NO2 All nonattainment & maintenance 100

PM10

Moderate nonattainment and 

maintenance (SJV Air Basin) 100

Lead (Pb) All nonattainment & maintenance 25

Note: Federal de minimus threshold levels in bold type are those where status is non-attainment or maintenance.

Definition of de minimus: so small or minimal in differences that it does not matter or the law does not take it into 

consideration.

California Clean Air Act

Responsibility for achieving California’s air quality standards, which are more stringent than 

federal standards, is placed on the Air Resource Board (ARB) and local air districts, and is 

to be achieved through district-level air quality management plans that are incorporated into 

the State Implementation Plan (SIP). In California, the EPA has delegated authority to 

prepare SIPs to the ARB, which in turn has delegated that authority to individual air districts.

The ARB has traditionally established state air quality standards, maintaining oversight 

authority in air quality planning, developing programs for reducing emissions from motor 

vehicles, developing air emission inventories, collecting air quality and meteorological data, 

and approving SIPs.

Responsibilities of air districts include overseeing stationary source emissions, approving 

permits, maintaining emissions inventories, maintaining air quality stations, overseeing 

agricultural burning permits, and reviewing air quality–related sections of environmental 

documents required by California Environmental Quality Act (CEQA).
Kings River Experimental Watershed Project 8 November, 2010 

Sierra National Forest

High Sierra Ranger District

The California Clean Air Act (CCAA) of 1988 substantially added to the authority and 

responsibilities of air districts. The CCAA designates air districts as lead air quality planning 

agencies, requires air districts to prepare air quality plans, and grants air districts authority to 

implement control measures. The CCAA focuses on attainment of the state ambient air 

quality standards, which, for certain pollutants and averaging periods are more stringent 

than the comparable federal standards.

The CCAA requires designation of attainment and nonattainment areas with respect to state 

ambient air quality standards. The CCAA also requires that local and regional air districts 

expeditiously adopt and prepare an air quality attainment plan if the district violates state air 

quality standards for CO, sulpher dioxide (SO2), NO2, or ozone. These air quality attainment 

plans are specifically designed to attain these standards and must be designed to achieve 

an annual 5% reduction in district-wide emissions of each nonattainment pollutant or its 

precursors. Where an air district is unable to achieve a 5% annual reduction in district-wide 

emissions of each nonattainment pollutant or its precursors, the adoption of “all feasible 

measures” on an expeditious schedule is acceptable as an alternative strategy (Health and 

Safety Code Section 40914(b)(2)). No locally prepared attainment plans are required for 

areas that violate the state PM10 standards, but the ARB is currently addressing PM10

attainment issues.

The CCAA requires that the state air quality standards be met as expeditiously as is 

practicable but, unlike the federal CAA, the CCAA does not set precise attainment 

deadlines. Instead, the CCAA establishes increasingly stringent standards for areas that will 

require more time to achieve the standards.

Local Air Districts

Local districts are given the responsibility to develop programs and plans for achieving both 

Federal and State air quality standards and are given the authority to implement control 

measures to reduce emissions of each nonattainment pollutants or its precursors. This is 

implemented through the use of Rules and Regulations. 

Smoke Management

In accordance with the California Code of Regulations, Title 17, all persons or entities

subject to subchapter 2 Smoke Management Guidelines for Agricultural and Prescribed 

Burning shall comply with the requirements therein and those requirements adopted by 

applicable districts in local smoke management regulations. Such persons or entities 

proposing to conduct prescribed burning must submit a smoke management plan to the air 

district of jurisdiction and: 1) receive a permit to burn, 2) receive authorization to burn on a 

given day, and 3) maintain communication with the local air district and report on the status 

of the burn until it is concluded.

San Joaquin Valley Air Pollution Control District

As agreed upon by San Joaquin Valley Air District staff and the Southern Sierra Interagency 

Smoke Management Group, all land managers planning to implement prescribed fire 

treatments will follow the Unified Guidelines and Procedures for Smoke Management, which 

includes the submission of a required Prescribed Fire Burn Plan and Smoke Management 
Kings River Experimental Watershed Project 9 November, 2010 

Sierra National Forest

High Sierra Ranger District

Summary. These are reviewed by district personnel and are conditionally approved. 

Burners are required to register prescribed burns prior to the fall burn season and 

authorization to burn is required prior to ignition based on air quality conditions and 

forecasts. For Prescribed Understory burning, seven days prior to ignition a Prescribed Fire 

Ignition Advisory form must be completed and submitted to district meteorology and 

compliance staff to begin receiving forecast for burn day potential. Participation on daily 

smoke management conference calls for burn project coordination is also required on a 

daily basis prior to and during implementation. On the day of ignition, final approval must be 

received from the compliance officer at the district. Pile burning approval is received 

through the calling the Hazard Reduction Burning phone number on a daily basis. A burn 

fee is applied to the total blackened acres accomplished on a yearly basis. These 

conditions are enforced through Air District Rules and Regulations (Rule 4103, Rule 4106).

Prevention of Significant Deterioration

The Prevention of Significant Deterioration (PSD) provisions of the CAA require measures to 

“preserve, protect and enhance the air quality in national parks, national wilderness areas, 

national monuments, national seashores, and other areas of special national or regional 

natural, recreation, scenic or historic value.” The most stringent requirements for air quality 

apply to those established as Class I areas. These include international parks, national 

wilderness areas greater than 5,000 acres, national memorial parks greater than 5,000 

acres, and national parks greater than 5,000 acres, and national parks greater than 6,000 

acres established prior to August 7, 1977. There are no Class I airsheds within the project 

area. However, there are Class I airsheds nearby that must be considered and protected. 

These airsheds are listed in the Table below.

Table 3. Class I Airsheds near the KREW project.

Class I Airshed Proximity to Project Area

Kings Canyon National Park Western Park boundary 

approximately 7 miles East of project 

area.

Dinkey Lakes Wilderness Southern wilderness Boundary is 

approximately 8 miles north of the 

projects area.

John Muir and Monarch Wilderness 

Areas

Western wilderness boundaries 

approximately 4 miles east of project 

area.

Visibility Protection

Visibility is an air-quality related value that is protected in all federal Class I areas. Since 

1984, states have been required to protect the visibility in national parks and wilderness 

areas, as mandated by the 1977 Clean Air Act Amendments. The 1977 amendments 

established a national goal for the “prevention of any future and the remedying of any 

existing impairment of visibility in mandatory Class I federal areas which impairment results 
Kings River Experimental Watershed Project 10 November, 2010 

Sierra National Forest

High Sierra Ranger District

from manmade pollution.” The regulations specifically require states to consider strategies 

for reducing visibility impairment from prescribed burning.

Existing Condition

The air quality in the San Joaquin Valley is among the poorest in the state. On average, the 

San Joaquin Valley experiences 35–40 days when it exceeds the federal health-based 

standards for ground-level ozone, and more than 100 days when it exceeds the state ozone 

standard. While levels of airborne particulates exceed the federal standard less than five 

times annually, the state standard is set at a lower and more protective level. The valley 

exceeds the state particulate standard an average of 90–100 days per year

(www.arb.ca.gov; Trends Summary).

Desired Conditions

The desired condition for Air Quality and Visibility in KREW is to meet the purpose and need 

for KREW while accomplishing the Sierra National Forest Land and Resource Management 

Plan goal to manage Forest activities so air quality is compatible with federal, state and local 

laws, including a program that achieves the Clean Air Act responsibilities.

ENVIRONMENTAL CONSEQUENCES

Methodology 

For each alternative proposed for KREW, associated emissions are calculated. This is used 

to determine if any alternatives total direct and indirect emissions fail to be (1) below Federal 

de minimus thresholds, in this case thresholds for ozone (precursors NOx and VOC) and 

PM10, or (2) considered regionally insignificant (less than 10% of the area’s total emissions 

inventory for that particular pollutant). If any alternative’s estimated emissions do not meet 

either of these conditions, a General Conformity Determination must be performed to 

ascertain how the proposed action would conform to the applicable SIP. 

Emissions Modeling-Smoke 

Four pieces of information are needed to calculate potential emissions produced from either 

wildfire or prescribed fire; acres burned, fuel loading, fuel type and type of burning (pile, 

understory or wildfire) that can determine the amount of fuel consumed. The actions 

proposed by each alternative are used to estimate these as well as information within the 

Fire/Fuels Report-Kings River Experimental Watershed Forest Health and Research Project. 

Associated emissions for criteria pollutants are derived utilizing an emissions spreadsheet 

developed and approved for prescribed fire emission reporting purposes. This form was 

developed and built by the Interagency Smoke Management Group and San Joaquin Valley 

APCD staff from emission formulas from publications (EPA, AP-42).

Modeling Used in Analysis

Associated emissions for criteria pollutants are derived utilizing an emissions spreadsheet 

developed and approved for prescribed fire emission reporting purposes. This form was 

developed and built by the Interagency Smoke Management Group and San Joaquin Valley 

APCD staff from emission formulas from publications (EPA, AP-42).
Kings River Experimental Watershed Project 11 November, 2010 

Sierra National Forest

High Sierra Ranger District

ProbAcre 2004 (M. R. Wiitala, Aviation and Fire Management, USDA Forest Service, 

Pacific Northwest Region). ProbAcre is a computer program that predicts the chance that a 

protection area will receive catastrophic consequences from a single or series of wild fire 

events over time. The modeling is based upon historical fire frequency records of the Sierra 

National Forest dating back to 1911.

Forest Vegetation Simulator with the Fire/Fuels Extension was used to model PM2.5 

emissions to show a comparison between the action and no-action alternatives. PM2.5 was 

used as a surrogate for PM10 emissions. FVS models a fire in the year 2022, 10-years after 

treatments.

Emissions Modeling- Vegetation Harvesting Equipment

Information needed to calculate associated emissions produced by vehicular traffic from 

road work and mechanical treatments included in Alternatives 2, 3, 4 and 5 (thinning 

operations, mastication and dozer piling) are; type of equipment and the number of hours 

this equipment is expected to run. The actions proposed by each are used to estimate 

these. Equipment hours are based on average production rates from similar projects. 

Equipment typically used for this type of work include heavy duty diesel-powered vehicles 

(tractor-trailers [log trucks], wheeled skidders and loaders, track type dozers/masticators, 

and road graders). Emission factors for criteria pollutants are from “A Desk Reference for

NEPA Air Quality Analysis” (CH2Hill 1995) and converted to total tons of pollutant.

Fugitive Dust Emissions

The Forest Service routinely requires timber sale operators to abate dust during use of the 

forest development roads. This is required for several reasons among which are: retaining 

road surface fines which help keep the larger supporting aggregate together; reduce dust 

visibility traffic hazards; reduce environmental dust plumes; and minimize loose fine material 

accumulations which can create muddy, road rutting conditions. (Lowe, 1994)

Fugitive (visible) dust emissions (VDE) by general vehicle movement are calculated at 10 

pounds per day for 5 vehicles per day on unpaved roads. This figure is reduced to 3.63 

pounds per day per mile of VDE after dust abatement. This is accomplished through 

watering of roads or other dust abatement measures which are incorporated into the project 

design. Dust abatement is required for roads below 3000 feet in elevation in the San 

Joaquin Valley Air Basin. KREW is above 3,000 feet in elevation and is exempt from 

Regulation VIII, Rule 8011 General Requirements (www.valleyair.org), though dust 

abatements are still required by the Forest Service.

Because of this exemption and the use of abatement measures when they are not a 

requirement, specific calculations for fugitive dust emissions are not used in the analysis of 

potential emissions from this project, but are considered part of the direct, indirect and 

cumulative effects. 

Indicators

No adverse effects; all prescribed burning will be in compliance with approved Burn Plan; 

fugitive dust will be minimized by required contract specifications (road watering).
Kings River Experimental Watershed Project 12 November, 2010 

Sierra National Forest

High Sierra Ranger District

Assumptions

This determination assumes that prescribed burning will occur under optimal atmospheric 

conditions for the transport of smoke and pollutants away from the San Joaquin Valley as 

regulated by SJVAPCD. Burning of natural and activity created dead and down woody 

material would occur under Best Available Control Measures for Air Quality as defined in 

Chapter 2.

Alternative 1 – No Action

No actions would be taken to reduce the potential for wildland fire. The opportunity would be 

loss for undertaking treatments to reduce the impacts that a wildland fire, starting in hot dry 

conditions, would cause the environment; both the forest environment and the airshed.

Direct and Indirect Effects

Direct Effects 

No direct effects from management actions to air quality or visibility would occur under this 

alternative since no treatments would be completed outside of that which is already 

permitted or authorized. 

Indirect Effects 

Indirect effects include the potential for unplanned and uncontrolled wildfire that could occur 

within the area. The resultant smoke caused by these would have large amounts of 

emissions released and could potentially be of long duration. Values measured such as 

PM10 and visibility range used to determine the Health-Protective Value would be in the 

ranges assumed to be Unhealthy. Values associated with this rating are PM10 ranging from 

176 to 300 μg/m3 and visibility of 1.24 to 2 miles (considered moderate smoke conditions). 

This would be considered the lower of the Health-Protective Values a wildfire would 

produce, if it occurred in the area. It is anticipated that for short periods of time the values 

may rise to the levels considered Very Unhealthy or perhaps Hazardous. The Statewide 

Emission Inventory in 2002 reported emissions (tons/day, annual average) from wildfires 

(Ahjua 2006) and is demonstrated in Table 4.

Table 4. Statewide Emission Inventory 2002 for Natural Sources-Wildfire

Emissions Total 

Organic

Gases

Reactive 

Organic 

Gases

Carbon 

Monoxide

Nitrogen 

Oxides

Sulfur 

Oxides 

PM10

Natural Sources:

Wildfire

6,522 3,046 17,474 3,441 302 2,418

Total Organic Gases (TOC) and Reactive Organic Gases (ROC) are similar to Volatile Organic Gases (VOC) 

and all are used by the air resources board to describe gases that lead to Ozone formation.

The high summer temperatures and light wind speeds that occur during the summer 

months, places a cap on valley air with no means for cleansing itself by dispersion or 
Kings River Experimental Watershed Project 13 November, 2010 

Sierra National Forest

High Sierra Ranger District

transport. Because of the poor air quality associated with the San Joaquin Valley Air Basin it 

does not take large amounts of additional emissions to degrade air quality into unhealthy 

ranges especially in the summer and fall months, where storm systems are less likely to 

occur and disperse smog and emissions. Emissions from a wildfire could potentially have 

long lasting impacts beyond the initial burning period because of this. Uncontrolled wildfires

are clearly responsible for the most widespread, prolonged, and severe periods of air quality 

degradation (Ahuja, 2006). For comparison purposes with the proposed action alternatives;

Table 5 below demonstrates the emissions produced from a wildfire if the acres in KREW 

were affected by an uncontrolled wildfire during typical fire season conditions. 

Table 5. Potential emissions if a wildfire were to burn within the entire KREW area.

Emissions:

Fuel 

Type 

Total 

Acres

Fuel 

Loading 

(Tons/ 

acre)

Total 

tons

Tons 

PM10

Tons PM2.5 Tons NOx Tons 

SO2

Tons 

VOC

Tons 

CO

Forest 3000 35 105000 1286.0 1155 183.7 5.35 761.25 12232.5

Based on 40 years of historical fire occurrence data (1965-2005) the ProbAcre model 

predicts a 30% chance of a 3,000 acre fire occurring on the High Sierra Ranger District in a 

20 year period.

The 1994 Big Creek Fire on the High Sierra Ranger District serves as an actual example of 

emissions produced from a wildfire burning in untreated fuels. It burned with high intensity 

causing 84% mortality in the timber stands. The 5600 acre fire created 2,388 tons of PM10. 

(District Forest Vegetation Simulator files 2005).

Cumulative Effects 

Typically the High Sierra Ranger District (HSRD) underburns 2000 acres per year, this 

program would continue unaffected by the alternative chosen. The district’s underburn 

program covers approximately 17,000 acres. None of these are within the project area. The 

underburns are in ponderosa pine or mixed conifer vegetation and have had at least one 

entry of prescribed fire. They are considered to be in maintenance status and will continue 

to be burned on a rotational schedule. Cumulative effects may also be the occurrence of 

respiratory or pulmonary distress if a wildland fire were to occur in the area while a 

prescribed fire was being conducted. This would be a rare occurrence. Table 3-1 displays 

the tons of estimated emissions from the HSRD underburns each year. The 73.5 tons of 

PM10 emissions is the cumulative effect for the underburn program by project. It reflects the 

potential smoke emissions affecting residents of the Fresno metropolitan area and local 

foothill communities.
Kings River Experimental Watershed Project 14 November, 2010 

Sierra National Forest

High Sierra Ranger District

Table 6. Tons of Estimated Pollutants per Individual Project—Annual Underburn Program of 

Work

PM10 PM2.5 NOx SO2 VOC CO

73.5 66.0 10.5 0.30 43.5 699.0

PM10 = Particulate matter <10 microns in size, PM2.5 = Particulate matter <2.5 microns in size, NOX = Nitrous 

oxide, SO2 = Sulfur dioxide, VOCs = Volatile Organic Compounds, CO = Carbon monoxide

Past analysis has shown that emissions associated with thinning operations and road use is minimal due to 

contractual dust abatement requirements.

Common to Alternatives 2, 3, 4, and 5

Treatments are proposed to reduce surface, ladder fuels, and some aerial fuels to meet 

the purpose and need of reducing stand densities to improve forest health and reduce the 

potential for uncharacteristically severe wildfire. This is to occur, if these alternatives were 

chosen, through the use of mechanical methods as well as management ignited fire in the 

form of prescribed fires such as pile burning, and understory burning. Prescribed fire 

would be applied to the project area for three purposes: (1) as a final “cleaning” after 

vegetation management treatments to further reduce 1, 10 and 100 hours fuels (those 

fuels that have the greatest influence on fire spread); (2) to maintain the lower levels of 

the 1, 10, and 100 hours fuels; (3) to reintroduce the fire element back into a fire 

dependent ecosystem.

As part of the KREW research, all treatment activities need to be completed in a two year 

time frame from initial implementation. All thinning treatments would be completed in year 

one and post thinning burn treatments would need to be completed in year two (this 

means all post-thinning burn treatments need to be ignited within one season) after 

beginning implementation to evaluate the watershed scale effects of the management 

activities. Each project, Providence and Bull, would be implemented in successive years 

to allow for firing operations to be completed in successive years and not in a single year. 

Dependent on where and how prescribed fire treatments are being utilized, the fuel 

loading can range from 15 to 34 tons per acre and be in the form of machine or hand 

created piles and/or in concentrations across a broad area such as the case in understory 

burning. On average the fuel loading for an area requiring prescribed fire as a primary 

treatment, maintenance and/or post activity treatment would be 35 tons/acre. 

The main focus of prescribed fire implementation is to reduce surface fuel loadings that 

contribute to fire behavior rates of spread and flame length. These are the 1, 10 and 100 

hour time lag categories (mainly needles, twigs and branches less than 3 inches in 

diameter). Prescribed fire burn plans set objectives for what percent consumption of 

these fuels are to be accomplished by the implementation of the prescribed fire. For pile 

burning, burn plan objectives typically set the objective at 80 to 90 percent consumption. 

Pile burning is conducted when the fuels have had a period of time to dry and are no 

longer green. For understory burning, burn plan objectives typically set the objectives at 

approximately70 percent consumption (or reduction) of these fuels, though this would not 

be across the entire burn area. A typical understory burn is implemented to create a 

“mosaic” burn pattern, leaving patches of unburned areas amongst burned areas.
Kings River Experimental Watershed Project 15 November, 2010 

Sierra National Forest

High Sierra Ranger District

Alternative 2—Uneven Aged Structural Restoration

Associated emissions from mechanical equipment used in thinning and hauling operations and 

emissions produced from burning are shown below. Hazard fuels treatments, including 

prescribed fire, proposed for this proposed action can be found in Chapter 2 – Alternatives 

Considered in Detail of the KREW Environmental Impact Statement.

Direct Effects

Smoke Emissions

This alternative proposes to accomplish a total of 2,294 acres of prescribed fire; both 

underburning and pile burning combined. When completed, prescribed fire activities proposed 

under this action would create the following emissions.

Table 7. Total Emissions from All Prescribed Fire Treatments Proposed in this Action (in tons)

Treatment

Type

Tons 

per 

acre

Total 

Acres PM10 PM2.5 NOx SO2 VOC CO

Hand Pile 15 15 0.88 0.82 0.59 0.00 0.71 7.43

Dozer Pile 35 725 98.96 92.62 65.08 0.13 79.93 837.38

Mastication/ 

Underburn 35 68 28.73 25.80 4.10 0.12 17.00 274.19

Underburn 

Only 20 838 205.31 184.36 29.33 0.84 121.51 1952.54

Lop & 

Scatter/ 

Underburn

35 648 277.83 249.48 39.69 1.13 164.43 2642.22

PM10 = Particulate matter <10 microns in size, PM2.5 = Particulate matter <2.5 microns in size, NOX = Nitrous 

oxide, SO2 = Sulfur dioxide, VOCs = Volatile Organic Compounds, CO = Carbon monoxide

The following table is a product of FVS modeling. It compares the estimated PM2.5 

emissions from the no action and action alternatives of a simulated wildfire occurring 

approximately 10 years after the completion of all project activities.
Kings River Experimental Watershed Project 16 November, 2010 

Sierra National Forest

High Sierra Ranger District

Figure 1. Total Tons PM2.5 by Alternative

After ten years the effects on air quality of the proposed treatments are still noticeable. 

Appling Alternative 1 the wildfire produces approximately 220 tons per acre of PM2.5. Under 

the Alternatives 2 through 5 the wildfire produces approximately 98-104 tons per acre. 

 Vegetation Harvesting Equipment 

Equipment hours are based on average production rates from similar projects on the HSRD. 

Most of the material would be thinned by chainsaw and skidded. Piling and mastication of activity 

created slash and brush would be with a track type tractor. For this analysis , all emissions are 

based upon use of wheeled skidders and loaders, heavy duty diesel powered highway truck and 

track type dozer or dozer with mastication head. 

Table 8. Total Emissions from all Thinning Operations (in tons)

Type of 

Equipment

Total 

Number 

of Hours PM10

Exhaust 

Hydrocarbons NOx CO SO2

Wheeled

skidder 1280 0.087 0.12 0.081 2.3 .058

Wheeled 

Loader 360 0.031 0.045 0.034 0.103 0.033

Heavy Duty 

Diesel 

Powered 

Truck 4000 0.512 0.384 8.32 3.58 0.908

Track 

Dozer 1254 0.070 0.076 0.80 0.22 0.086

0

100000

200000

300000

400000

500000

600000

700000

Alt 1. No 

Action

Alt 2. 

Uneven 

Aged Mgmt

Alt 3. Fuels 

Reduction

Alt 4. North 

GTR 

Alt 5. 

Proposed 

Action -

Hybrid

672540

317928 302643 299586 308757

Kings River Experimental Watershed

Total Tons PM10

Potential Smoke Severe Fire

Total Tons

Fire Year 2022
Kings River Experimental Watershed Project 17 November, 2010 

Sierra National Forest

High Sierra Ranger District

 Fugitive Dust Emissions 

The Forest Service routinely requires timber sale operators to abate dust during use of the forest 

development roads. This is required for several reasons, including retaining road surface fine 

particles, which helps keep the larger supporting aggregate together; reducing dust visibility 

traffic hazards; reducing environmental dust plumes; and minimizing loose fine material 

accumulations which can create muddy, road rutting conditions (Lowe 1994 as cited in USDA 

Forest Service 2008).

Visible dust emissions (VDE [PM10]) by general vehicle movement are calculated at 10 lbs per 

day for 5 vehicles per day on unpaved roads. This figure is reduced to 3.63 pounds per day per 

mile of VDE after dust abatement through watering of roads or other dust abatement measures, 

which are incorporated into the project design features. For the proposed action, 3.63 pounds 

per day x 22 days to haul = 79.86 pounds, which is below de minimus. De minimus is set at 100 

pounds per day for 50 vehicle trips on unpaved roads. Dust abatement is required for roads 

below 3,000 feet in elevation. The Dinkey South project area is above 3,000 feet in elevation and 

is exempt from Regulation VIII, Rule 8011 General Requirements, though dust abatement is still 

required by the Forest Service.

Table 9. Emissions conformity to General Conformity Rule for Criteria Pollutants

TOTAL 

Emissions 

(smoke and 

equipment)

PM10

612.4

PM2.5

553.1

NOx

148.9

Percent of 

Areas 

Total

1.45% 0.5% 0.08%

Criteria Pollutants are those that determined by EPA to have de minimus levels

Determination

The conformity decision for the Clean Air Act prohibits federal agencies from permitting or 

approving any activity that does not conform to the SIP. The California Air Resources Board 

under the General Conformity Rule regulates actions that require conformity determinations 

for specific pollutants. The California Air Resources Board rules indicate that projects would 

be determined to conform to the applicable SIP if it meets the following criteria:

1. The total direct and indirect emissions from the action is in compliance with all 

requirements of SIP, because the actions meet one or more of the following:

a. The emissions from the action are identified and accounted for in the applicable SIPs 

attainment or maintenance demonstrations,

b. The emissions are offset,

c. Based on air quality monitoring, the actions do not:

i. Cause or contribute to any new violation of any standard in any area, or

ii. Increase the severity or frequency of any existing violations of any standard,

d. The state commits to modify SIP in accordance with the EPA rules, or
Kings River Experimental Watershed Project 18 November, 2010 

Sierra National Forest

High Sierra Ranger District

e. Where the EPA has not approved a revision of the relevant SIP, the total emissions 

do not exceed the historical level (based on the calendar year 1990 or other 

appropriately agreed to year).

This project meets the General Conformity Rule; it does not interfere with the strategies 

employed to attain NAAQS. The emissions from this project are considered regionally 

insignificant (total emissions are less than 10%) of the area’s total emissions inventory for

PM10 and NOx. This conformity is accomplished by maintaining burn ignitions and acres 

within rules and guidelines developed by the San Joaquin Valley Unified Pollution Control 

District (District), as provided for by the California Air Resources Board, under the Unified 

Guidelines for Smoke Management as developed by the Southern Sierra Interagency 

Smoke Management Group. These guidelines and rules are based on the requirements 

found in the following:

Title 17 of the California Code of Regulations – Subchapter 2, Smoke management 

Guidelines for Agriculture and Prescribed Burning

San Joaquin Valley Unified Air Pollution Control District Rule 3160 (Prescribed 

Burning Fee), Rule4106 (Prescribed Burning and Hazard Reduction Burning), and 

the District’s Smoke Management Program, Rule 4103 (Agricultural Burning)

Wildland Fires Coordination and Communication Protocol as it applies to the Current 

Smoke Management Program

Public Resource Code 4291 – for hazard Reduction Burning in the foothill and 

mountain areas of the District.

Based upon meeting the SIP standards of CARB, the Unified Smoke guidelines discussed 

above and SJVUAPCD rules, the project is determined to be in compliance with SIPs 

General Conformity Rule and Title 17 of the California Code of Regulations. It is important 

when considering the determination that compliance with SIP is based upon meeting rules 

and guidelines managed by SJVUAPCD. These rules and guidelines are designed to meet 

historical emissions levels and keep projects from violating the SIP. The alternatives 

propose activities that will meet the rules and guidelines. Rules and guidelines along with 

daily SJVUAPCD direction control acres and ignitions. Meeting the acres and ignition rules 

and guidelines meets conformity with the SIP emission standards.

Exhaust hydrocarbons and pollutant levels produced from thinning activities are lower than 

historical levels of logging and similar activities for the Sierra National Forest. Historical 

timber harvesting and thinning operations were at all time highs in 1987 with 154 million 

board feet of timber harvested. This alternative only thins to 2.5% of that historical level.

Indirect Effects 

The Fresno Metropolitan area, the communities of Shaver Lake, Auberry, Tollhouse, 

Providence Creek, Exchequer, the Dinkey Creek and Wishon Recreation Areas are 

considered smoke sensitive areas. These areas could be affected by smoke if weather 
Kings River Experimental Watershed Project 19 November, 2010 

Sierra National Forest

High Sierra Ranger District

patterns produce a stable air mass and smoke is unable to vent into the upper atmosphere. 

Since PM10 and ozone are public health hazards, prescribed burns would be planned during 

periods of unstable air, which would allow for proper ventilation of smoke and temperatures 

less than 95 degrees. However, since prescribed underburns could last for several days or 

weeks there is the potential for recurring shifts in air masses toward more stable conditions. 

For this reason, all prescribed fire activities are coordinated with SJVAPCD and would be 

implemented under optimum conditions using best available control measures (listed in the 

Proposed Action) to prevent smoke concentrations from affecting local communities. 

Indirect effects may also be the occurrence of respiratory or pulmonary distress if a wildland 

fire were to occur in the area while a prescribed fire was being conducted. This would be a 

rare occurrence. Emissions from wildfires subside into the San Joaquin Valley during stable 

summer air patterns; smoke emissions from wildfires cause air pollution alerts not only in 

local mountain communities but also in the valley.

Cumulative Effects 

The potential cumulative effects are from exposure to organic hydrocarbons (precursors to 

smog under high daytime temperatures), large particulate matter, and PM10 and PM2.5

produced from prescribed burning. These emissions are easily inhaled and cause 

respiratory and pulmonary distress. 

The dispersion of pollutants is affected by local meteorological conditions. Pollutants can 

stay trapped in one place if there is no mixing caused by wind and temperatures. Prescribed 

burns are conducted on days when atmospheric ventilation transports smoke and pollutants 

away from the San Joaquin Valley and pollutants are not normally a problem. Burns are 

conducted on authorized burn days only in consultation with the APCD. Poor ventilation 

occurs during summer and fall months when the valley is characterized by relatively stable 

air masses. Ozone concentrations can reach peak levels when strong sunshine and 

temperatures above 95 degrees F accompany periods of poor ventilation. Although ozone is 

not released directly to the atmosphere, it is produced by chemical reactions involving VOCs 

and NOX. The meteorological factors favorable to significant ozone formation occur only 

during the summer. 

Cumulative Effects—On-Going District Projects 

The HSRDs prescribed fire program would continue as part of the district program of work. 

All of the prescribed fire projects have gone through an air quality analysis during the NEPA 

process. The cumulative effect of smoke emissions and degradation of visibility may occur if 

prescribed burns were to continue during stable atmospheric conditions that are present 

when wildfires occur. For this reason, all prescribed fire activities are coordinated with 

SJVAPCD and would be implemented under optimum conditions using best available 

control measures to prevent smoke concentrations from affecting local communities. 

Cumulative Effects – Past, Present and Reasonably Foreseeable Projects 

Other past, present and foreseeable projects on the High Sierra District that could contribute to 

cumulative effects include the afore-mentioned district prescribed burn program, The Dinkey North 
Kings River Experimental Watershed Project 20 November, 2010 

Sierra National Forest

High Sierra Ranger District

and South projects, cattle grazing, the district plantation and vegetation management program 

(Snowy-Patterson project), the proposed Dinkey Landscape projects (Soaproot and Eastfork), Off 

Highway Vehicle (OHV) use, and private land management activities and timber sales. Cumulative 

effects to air quality include any vegetation management program (public or private) in which 

vegetation will be burned, or where vehicle and heavy equipment use contributes to exhaust 

emissions or fugitive dust. The projects that could and possible will contribute to air quality 

cumulative effects from particulate matter PM10 and NOx include Southern California Edison (SCE) 

Company’s forestry and prescribed fire program, the HSRD plantation and vegetation management 

program, and the vegetation treatments as prescribed in the Dinkey Collaborative Forest Landscape 

Restoration program (CFLR) which includes the Dinkey North and South projects and the proposed 

Soaproot and Eastfork projects. Cumulative effects to air quality from exhaust emissions and fugitive 

dust can be expected from the SCE forestry program, the CFLR, OHV use and the HSRD vegetation 

management program including plantation management.. It is unknown how much heavy 

equipment use or prescribed burning may take place as part of the SCE program but it is anticipated 

that up to 1500 acres of vegetation management and 400 acres of prescribed burning may occur. It 

is unknown how much vegetation management may occur on private property. All prescribed burn 

activities on private and public lands follow the same general conformity rules and are governed by 

the decisions of the SJVAPCD as the SNF.

Alternatives 3, 4 and 5, 

Direct, Indirect, and Cumulative Effects

The same acreage of burning and thinning as described in Alternative 2 will be conducted 

under Alternatives 3, 4 and 5. The effects of these alternatives are similar to those under 

Alternative 2. The changes in the diameter limit of thinning among the alternatives alter the 

amount of trees removed under each alternative. These changes alter the amount of 

emissions that would be generated by prescribed fire. The differences in each alternative 

are represented by the amount of smoke that would be produced by a wildfire. Figure 1 

shows that there is little difference in the action alternatives and the amount of smoke that 

is produced 10 years post burn by a wildfire.

Comparison of Alternatives

The emission of pollutant PM2.5 is used as a surrogate to represent PM10. Table 3.1-10 below 

shows that the proposed action and the action alternative are effective in reducing total tons of 

pollutants as compared to the No Action Alternative.
Kings River Experimental Watershed Project 21 November, 2010 

Sierra National Forest

High Sierra Ranger District

Table 3.1-10. Comparison of alternatives, effectiveness of treatments in reducing smoke 

particulates.

Total 

Tons 

of 

PM2.5

Tons per 

acre of PM 

2.5

Percent 

Reduction

Alternative 1 – No Action 672510 220 *

Alternative 2 – Uneven Aged 

Management (Structural Restoration) 317928 104 47%

Alternative 3 – Fuels Reduction 302643 99 45%

Alternative 4 – North GTR (Process 

restoration) 299586 98 45%

Alternative 5 – Proposed Action 

(Hybrid Forest Health Restoration) 308757 101 46%

*Percent reduction in emissions in tons per acre in action alternatives versus no action 

alternative.

Design Criteria

Air Quality 

The following are best available control measures (BACMs) for prescribed fire as required under 

Section 190 of the Clean Air Act, as amended in 1990. The U.S. Environmental Protection Agency 

(EPA) developed implementation strategies and BACM for areas that are designated serious nonattainment for particulate matter less than 10 microns (PM10) in 1992. Specific techniques to 

reduce fire emissions include the following:

Employ commonly used reduction techniques such as burning units after harvest before 

new live fuels appear; burning in the springtime prior to “green-up,” burning when 1,000-

hour fuels (woody debris larger than 3 inches in diameter) moistures are high, and burning 

when the duff is wet (after fall precipitation, or during winter and spring).

Employ avoidance techniques such as burning on cloudy days when the plume and residual 

smoke cannot be seen, burning during periods of atmospheric instability for better smoke 

dispersal, and burning during periods of low visitor use.

Employ techniques to optimize flaming combustion, including burning piled fuels rather 

than broadcast burning, reducing the amount of soil in piles, and employing rapid ignition to 

create a high intensity fire.

Ensure that all activities conform to the State Implementation Plan (SIP). 

Conduct a full conformity analysis, as required by the Clean Air Act and the SIP to assess 

whether the proposed action produces less than de minimus emissions. (For full 
Kings River Experimental Watershed Project 22 November, 2010 

Sierra National Forest

High Sierra Ranger District

determination, refer to the Kings River Project Air Determination, available in the project 

record.)
Kings River Experimental Watershed Project 23 November, 2010 

Sierra National Forest

High Sierra Ranger District

References

Ahuja, S. 2006. Fire and Air Resources, Chapter 21, Fire in California Ecosystems; 

Sugihara, N. Pages 481-498.

CHM2HILL. 1995. A Desk Reference for NEPA Air Quality Analysis, USDA Forest 

Service.

Environmental Protection Agency. AP-42, Compilation of Air Pollutant Emission Factors, 

Volume 1: Stationary Point and Area Sources. Fifth Edition.

Lowe, Tom, Fugitive Dust Analysis for Timber Haul on Unpaved Roads, Sierra National 

Forest, 1994. Unpublished. 6 pgs. Available on district.

Southern Sierra Smoke Management Group and San Joaquin Valley Air Pollution staff. 

Unified Guidelines and Procedures for Smoke Management, Unpuublished. March 2009.

Available on district.

U.S. Department of Agriculture, Forest Service (USDA-FS). 1992; Forest Land and 

Resource Management Plan-Sierra National Forest. Pacific Southwest Region, Sierra 

National Forest. Clovis, CA.

Marc R. Wiitala. 1999. Assessing the Risk of Cumulative Burned Acreage Using the 

Poisson Probability Model. Gen. Tech Rep. PSW-GTR-173. USDA Forest Service, Pacific 

Southwest Research Station. Pp.51-57.

www.epa.gov, Website for Environmental Protection Agency.

www.arb.ca, Website for California Air Resources Board.

www.valleyair.org, Website for the San Jaoquin Valley Unified Air Pollution Control 

District.