United States Environmental Protection Agency

General Permit for New or Modified Minor Sources of Air 

Pollution in Indian Country

http://www.epa.gov/air/tribal/tribalnsr.html

Background Document: General Air Quality Permit for New or Modified True 

Minor Source Sawmill Facilities

Version 1.0

Last Modified: July 2, 2014

1. Sawmill Source Category Definition

A sawmill facility is an operation that processes raw timber into dimensional lumber for shipping and eventual 

sale. A modern sawmill's basic operation is much like those of hundreds of years ago; a log enters on one end 

and dimensional lumber exits on the other end. Sawmill activities include sawing, planing, sanding, chipping and 

drying wood. The proposed General Air Quality Permit for New or Modified True Minor Source Sawmill Facilities

only covers sawmill operations that are located at true minor New Source Review (NSR) sources.

2. Source Category Characterization

A sawmill's basic operation involves several steps to turn logs into dimensional lumber:

 Logs are brought in by logging truck, rail or a log drive to the sawmill;

 Logs are scaled either on the way to the mill or upon arrival at the mill;

 Debarking removes bark from the logs;

 Decking is the process for sorting the logs by species, size and end use (lumber, plywood, chips);

 The head saw, head rig or primary saw, breaks the log into cants (unfinished logs to be further

processed) and flitches (unfinished planks) with a smooth edge;

 Depending upon the species and quality of the log, the cants will be further broken down by either a 

resaw or a gang edger into multiple flitches and/or boards;

 Edging trims all irregular edges off of the flitch, leaving four-sided lumber;

 Trimming squares the ends at typical lumber lengths;

 Drying removes naturally occurring moisture from the lumber (this can be done with kilns or the lumber 

can be air-dried);

 Planing smooth the surface of the lumber leaving a uniform width and thickness; and

 Shipping transports the finished lumber to market.

Sawmills typically derive their power from the electric grid. Dryers may be either direct-fired or indirect-heated.

Boilers are typically used to provide the heat for dryers. In direct-fired dryers, hot combustion gases from an 

onsite boiler are blended with recirculated exhaust from the dryer to lower the gas temperature to a level that

will not scorch the lumber. In indirect-heated dryers, air is warmed over steam coils and then circulated over the 

lumber. Dryers typically have one to three heated zones followed by a cooling zone or section. Each heated zone 

has a hot air source, fans to move the warm air, and an exhaust vent or stack. The cooling section circulates 

ambient air over the wood to reduce the temperature just before it exits the dryer. The lumber must be cooled 

before proceeding to the next step in the process.

Criteria pollutant emissions of concern are primarily particulate matter (PM) from sawing and planing (PM 

emissions from re-entrained road dust or sawdust particles can also be a concern), volatile organic compound 

(VOC) emissions from drying, and nitrogen oxides (NOx) from boilers and emergency diesel generators. For 
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sources with available water, water sprays may be used to control PM emissions. Dry PM control methods 

(baghouses, fabric filters and cyclones) may also be used to control PM emissions.

Sawmill facilities are common in areas with ample supplies of timber, including the southeast and northwest.

3. State Minor Source Permit Programs

The U.S. Environmental Protection Agency (EPA) researched state air quality permitting websites for examples of 

general permits and permits by rule for sawmill facilities. The EPA examined these documents for their 

applicability in developing a general permit for Indian country. The EPA incorporated elements from these 

permits in developing the documents and regulations in the general permit for sawmill facilities. The EPA 

examined general permit documents for sawmill facilities in Oregon and Texas. The EPA chose general permits 

from these states because of characteristics they possess:

 Readily available; 

 Clear throughput limits; and 

 Organization of the regulations followed the typical form for federal NSR permits:

o Limitations and standards, and 

o Monitoring, testing, recordkeeping, and reporting requirements.

Very few states appear to issue air general permits for sawmill facilities. The Texas Commission on 

Environmental Quality (TCEQ) refers to its permit as a standard permit. The Texas standard permit contains a 

processed lumber production limit of 25 million board-feet per any consecutive 12-month period for mills. 

Under this limit, air quality modeling used in the drafting of the permit indicates no adverse effects to human 

health. Emissions associated with production rates in excess of this figure would require a case-by-case analysis 

to ensure protection of human health. In order to ensure there are no adverse health effects, the TCEQ

performed air quality modeling to determine an appropriate setback distance from the site property line and 

operating restrictions for sawmill equipment.

The permit covers sawmills as facilities that process logs into lumber, including debarking, sawing, planing, 

drying, trimming, production of wood chips, and loading of lumber and wood residue. The permit does not 

authorize the manufacture of other wood products or the chemical treatment of lumber. 

If a site’s potential to emit (PTE) is at or above a major source threshold for the Federal Operating Permits 

Program, a certification must be submitted to the commission to avoid the requirement to obtain a federal 

operating permit. The commission expects most sawmills authorized by this standard permit will not be subject 

to the requirements of the Federal Operating Permits Program.

Facilities that are ineligible to use the standard permit include those that cannot meet setback requirements, 

major sources or major modifications that require federal NSR permitting, or those that are located at a site that 

constitutes a major source as defined by TCEQ regulatory code, 30 TAC Chapter 116. The standard permit cannot 

be used to authorize sawmills manufacturing wood products, except for wood chips, or chemically treating 

lumber. 

The TCEQ permit requirements include:

 Restrictions on hours of operation;
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 Open burning prohibition;

 Fire prevention measures;

 Minimum 150 foot setback from the sawmill property line;

 Fugitive dust controls;

 Sawmill residue and disposal removal maintenance in a manner minimizing entrainment;

 Prohibition on visible emissions at or beyond the property line;

 Opacity restrictions;

 Best available control technology requirements for boilers and other heating devices;

 Restrictions on the operation of standby internal combustion engines and generators for electric power 

generation; and

 Records of monthly and annual throughput of hardwood lumber converted to board-feet and fuel 

usage.

Oregon’s permit covers more activities than the Texas permit. It covers: saw milling, planing, milling, or mill 

working (including kitchen cabinets and structural members), 25,000 or more board feet/shift finished product 

and plywood manufacturing and/or veneer drying. All of the following conditions must be met in order for a 

source to qualify for the Oregon sawmill general permit:

 The permittee is performing activities listed on the cover page, including sawing, planing, sanding, 

chipping, kiln drying, plywood pressing and surface coating, along with supporting activities such as 

material conveyors (mechanical and pneumatic), veneer dryers, and boilers;

 A Simple or Standard Air Contaminant Discharge Permit is not required for the source; and

 The source is not having ongoing, recurring or serious compliance problems. 

The permit includes the following emission standards and limits:

 Visible opacity limits;

 PM limits for fuel burning equipment, non-fuel burning equipment and fugitive emissions sources;

 Combined PM emissions from all veneer and plywood mill sources within the plant site, including, 

but not limited to, sanding machines, saws, presses, barkers, hogs, chippers, and other material 

size reduction equipment, process and space ventilation systems, and truck loading and unloading 

facilities, must not exceed a plant specific average hourly emission rate (excluded from this 

standard are veneer dryers, fuel burning equipment, and refuse burning equipment); 

 PM limits for veneer dryers;

 Fugitive dust controls;

 PM fallout restriction;

 Nuisance and odor restriction; and

 Fuel type and fuel sulfur content restrictions.

4. Requirements for General Permits and Permits by Rule

4.1 Documents for General Permits and Permits by Rule

The EPA developed a standardized set of permit documents in support of a general permit for sawmill facilities 

located in Indian country. These consist of the following documents: 
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 Questionnaire: Assists the facility owner or operator in determining whether they are eligible for a 

General Air Quality Permit;

 Request for Coverage under the General Air Quality Permit: States the criteria for qualification, gathers 

information on the source, facility location, and source contact, and requests technical information on 

facility equipment, throughput, and attainment status;

 Instructions: Guides the applicant in filling out the Request for Coverage under the General Air Quality 

Permit;

 General Air Quality Permit, Terms and Conditions: Contains the requirements and regulations with 

which the source must comply. The emission limitations, monitoring, recordkeeping and reporting 

requirements are in the permit, including requirements for sources located in nonattainment areas; and

 PTE Calculator Spreadsheet: Allows applicants to calculate their PTE, based on owner inputs of the 

specific equipment present at their source, assuming continuous operation throughout the year. The 

PTE Calculator spreadsheet generates potential emissions, based on these inputs. The spreadsheet 

illustrates the correlation between equipment, raw material throughput, and emissions.

4.2 Exemption and Qualification for General Permits

Facilities applying for the proposed general permit must meet the following criteria:

 Must be a true minor NSR source; and

 Be below the emission limitations established for the general permit.

New facilities with a PTE or modifications to existing facilities with an emissions increase lower than the minor 

NSR thresholds specified in Table 1 of Indian Country Minor NSR rule (40 CFR 49.153) are exempt from the 

minor NSR program. The exemption thresholds for PM and criteria pollutants are listed in Table 1 below. 

Facilities applying for the proposed general permit may calculate their PTE using the PTE calculator provided to 

determine if they are exempt from the minor NSR program. The EPA is providing a PTE calculator to assist with 

this task.

 Table 1: Minor NSR Thresholds in 40 CFR 49.153

Pollutant Attainment Area Nonattainment Area

Carbon Monoxide (CO) 10 tons per year (tpy) 5 tpy

PM 10 tpy 5 tpy

PM10 5 tpy 1 tpy

PM2.5 3 tpy 0.6 tpy

Sulfur Dioxide (SO2) 10 tpy 5 tpy

NOX 10 tpy 5 tpy

VOC 5 tpy 2 tpy

Under current EPA policy, only true minor NSR sources qualify for the proposed general permit. Therefore, 

facilities will be required to compare their PTE to the NSR major source thresholds to determine if they qualify 

for the proposed general permit. For this source category – sawmill facilities – the NSR major source threshold 
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for attainment areas is 250 tpy of any criteria pollutant. The NSR major source thresholds for nonattainment 

areas are summarized in Table 2 below:

Table 2: NSR Major Source Thresholds for Nonattainment Areas

Pollutant Nonattainment Classification NSR Major Source Threshold

Ozone

Marginal 100 tpy of VOC or NOX

Moderate 100 tpy of VOC or NOX

Serious 50 tpy of VOC or NOX

Severe 25 tpy of VOC or NOX

Extreme 10 tpy of VOC or NOX

PM10

Moderate 100 tpy

Serious 70 tpy

CO Moderate 100 tpy

Serious 50 tpy

SO2, NOx, PM2.5 No nonattainment classification 100 tpy

If the facility’s PTE is above the NSR major source threshold of 250 tpy, or above the applicable nonattainment 

area thresholds listed in Table 2 (for any pollutant that is designated nonattainment in the area the source will 

locate), then the facility does not qualify for the proposed general permit. The following documents are 

available to assist sources in the screening and application process: 

 Questionnaire; and

 Request for Coverage under the General Air Quality Permit.

The questionnaire and the application for the sawmill permit contain questions designed to limit the availability 

of this general permit to true minor source sawmills. For facilities not exempt from the minor NSR program and 

having a PTE below the NSR major source thresholds, the facilities will further evaluate if they can meet the 

emission limitations established in this general permit. The specific requirements for the proposed general 

permit are discussed in Sections 4.3, 4.4, 4.5, and 4.6. Section 5 provides background on the emissions 

limitations provided in the proposed sawmills general permit.

4.3 Specific Permit Requirements for General Permits and Permits by Rule

The terms and conditions of the general permit were established according to the required permit content and 

analyses in the Indian Country Minor NSR rule. The required permit content is listed in 40 CFR 49.155(a) – What 

information must my permit include? Below we describe the basis for the permit conditions.

40 CFR 49.155(a)(1) – General Requirements

The rule establishes general requirements that each permit must identify: the effective date of the permit; the 

date by which the owner/operator must commence construction in order for the permit to remain valid; the 

emission units subject to the permit and their associated emission limitations; and monitoring, recordkeeping, 

and reporting requirements to assure compliance with the emission limitations. 

The proposed general permit contains all of this required information, except for the emission units subject to 

the permit. Because of the nature of general permits we believe it is more appropriate to identify the emission 

units covered by the general permit in the Approval of the Request for Coverage. The general permit 

incorporates the Approval of the Request for Coverage into the general permit. Each permit contains a separate 
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section that specifically identifies the emission limitations and standards, monitoring and testing, recordkeeping, 

and reporting and notification requirements.

CFR 49.155(a)(2) – Emission Limitations

The permit must contain the emission limitations determined by the reviewing authority under 40 CFR 49.154(c) 

for each affected emissions unit. 40 CFR 49.154(c) – How will the reviewing authority determine the emission 

limitations that will be required in my permit? – identifies the case-by-case control technology review that must 

be used by the reviewing authority to determine the appropriate level of control. In carrying out the case-bycase control technology review, the reviewing authority must consider the following factors:

1. Local air quality conditions;

2. Typical control technology or other emission reduction measures used by similar sources in surrounding 

areas;

3. Anticipated economic growth in the area; and

4. Cost-effective emission reduction alternatives.

In addition, the reviewing authority must require a numerical limit on the quantity, rate or concentration of 

emissions for each regulated NSR pollutant emitted by each affected emissions unit, for which such a limit is 

technically feasible. The emission limitation required may also be included as pollution prevention techniques, 

design standards, equipment standards, work practices, operational standards or any combination thereof. 

However, the emission limitations must assure that each affected emission unit will comply with all 

requirements of 40 CFR parts 60, 61, and 63, as well as any federal or tribal implementation plans that apply to 

the unit. Finally, the emission limitations required may not rely on a stack height that exceeds good engineering 

practice or any other dispersion technique, except as allowed by 40 CFR 51.118(b). 

To address the requirements for establishing emission limitations, the following considerations were used for 

setting the limits in the general permit for sawmill facilities:

1. Local air quality conditions – To address this requirement, the general permit requires sources locating 

in ozone nonattainment areas to meet more stringent emissions limitations for VOC emissions from kiln 

drying, the main source of VOC emissions at sawmill facilities. This will also ensure these sources are not 

major sources in those areas. Also, PM emission may be a concern at sawmill facilities, some of which 

can be fugitive. The permit contains a requirement to take corrective action if fugitive dust is visible 

beyond the property line. This will aid in reducing local PM air quality impacts.

2. Typical control technology or other emission reduction measures used by similar sources in surrounding 

areas – For sources locating in attainment areas the EPA looked at the control requirements required by 

40 CFR parts 60, 61 and 63. These regulations establish minimum technology and emission limitations 

that must be met nationally and also meet the requirements of 40 CFR 49.154(c)(4) to ensure 

compliance with parts 60, 61, and 63. For this general permit the EPA considered regulations that apply 

to the equipment at sawmill facilities:

a. Subpart Dc of 40 CFR Part 60 - New Source Performance Standards for Small IndustrialCommercial-Institutional Steam Generating Units;

b. 40 CFR 63 Subpart ZZZZ – National Emission Standards for Hazardous Air Pollutants for 

Stationary Reciprocating Internal Combustion Engines;

c. 40 CFR 60 Subpart IIII – Standards of Performance for Stationary Compression Ignition Internal 

Combustion Engines; and
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d. 40 CFR 60 Subpart JJJJ – Standards of Performance for Stationary Spark Ignition Internal 

Combustion Engines.

These regulations cover emissions from boilers and engines at sawmill facilities.

The derivation of the emission limitations in the general permit are discussed fully in Section 5. The 

minor NSR thresholds are based on provisions of the Review of New Sources and Modifications in Indian 

Country rule at 40 CFR 49.153 and are provided in Table 1. 

VOC emissions from all lumber drying kilns in ozone nonattainment and attainment areas must not 

exceed certain ton per year emissions limitations. Emissions from all planar mills shall be conducted 

within an enclosed building and emissions to the atmosphere shall be controlled using a 

baghouse/fabric filter during all times that the affected emissions unit operates. Emissions from outdoor 

sawmill operations shall be covered at all times that the affected emissions unit operates and all 

material handling operations must be controlled by a cyclone or baghouse/fabric filter. Emissions to the 

atmosphere from indoor sawmill operations shall be controlled by a baghouse/fabric filter during all 

times that the affected emissions unit operates. Lumber produced at each sawmill facility shall not 

exceed 25,000,000 board-feet per year based on a 12-month rolling total. This production limit is 

consistent with the two state general permits reviewed.

Liquid fuels shall contain no more than 0.0015 percent sulfur by weight. The permittee must keep a

supply of extra bags and other spare parts for the baghouse that must be maintained onsite. The 

permittee must comply with the permit’s fugitive dust control plan. Each affected emissions unit at the 

facility must not cause to be discharged into the atmosphere any gases that exhibit 20 percent opacity 

or greater averaged over any six-consecutive-minute period. All VOC-containing material (e.g., coatings, 

thinners, and clean-up solvents) must be stored in closed containers. All waste materials containing VOC 

(e.g., soiled rags) must be stored in sealed containers until properly disposed.

Emergency engines, based on model year, must be certified to existing emission standards and those 

engines not required to be certified have to meet certain maintenance requirements and performance 

testing requirements. Those engine using fuel oil must use diesel or biodiesel with a sulfur content not 

to exceed 0.0015 percent by weight. 

3. Anticipated economic growth in the area – The Reviewing Authority may consider anticipated economic 

growth when determining whether coverage under the proposed general permit is justifiable.

Considering, however, that the proposed general permit sets emission standards that are consistent 

with what is required of sawmill facilities in states in both attainment and nonattainment areas, we 

expect that this will not be a factor. 

4. Cost-effective emission reduction alternatives – The proposed general permit sets emission standards 

that are consistent with what is required by sawmill facilities in states, based on the particular 

attainment status where the source is locating. As such, the chosen technologies are considered widely 

available and consideration of more cost-effective alternatives is not necessary at this time. We intend 

to periodically review technology costs in the future to determine when more stringent, cost-effective 

technologies become widely available.

40 CFR 49.155(a)(3) – Monitoring Requirements
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The proposed general permit must include monitoring that is sufficient to assure compliance with the emission 

limitations that apply to the source. The proposed general permit requires inspections of baghouses/fabric 

filters and cyclones (once during each calendar week and month, respectively); weekly visible emissions surveys; 

weekly fugitive emissions surveys; and initial performance tests for affected emissions units.

40 CFR 49.155(a)(4) – Recordkeeping Requirements

The proposed general permit must include recordkeeping that is sufficient to assure compliance with the 

emission limitations and monitoring requirements, including certain statements listed in 40 CFR 49.155(a)(4)(i) 

and (ii). In addition to the recordkeeping requirements in 40 CFR 49.155(a)(4)(i), the proposed general permit 

also requires records of annual operating parameters for affected emissions units and products processed. The 

total VOC emitted from the lumber kilns must be recorded for each month since the last report and the 

permittee must show the 12-month total VOC mass emissions ending with that month. The permittee must

calculate the tons per year of VOC emissions in accordance with formula provided in an attachment to the 

permit. Each month's lumber drying kiln VOC emissions shall be determined as illustrated in Attachment A.

The permittee must record the types and monthly fuel use combusted in each emission unit on a continuous 

rolling 12-month period; dates and results of baghouse/fabric filter and cyclone inspections, visible emission 

surveys, and fugitive emission surveys; corrective actions taken as a result of each inspection and survey; results 

of corrective actions taken; results of performance tests; and engine data on fuel used and maintenance 

activities. For emergency engines, the permittee must maintain a log of the hours of operation, including the 

date, time, duration, and reason(s) for use.

40 CFR 49.155(a)(5) – Reporting Requirements

The proposed general permit includes the reporting requirements listed in 40 CFR 49.1559(a)(5)(i) and (ii) 

related to annual reports and reporting of deviations.

40 CFR 49.155(a)(6) – Severability Clause

The proposed general permit includes a severability clause to ensure the continued validity of the other portions 

of the permit in the event of a challenge to a portion of the permit. This condition is found in the General 

Provisions of the proposed general permit.

40 CFR 49.155(a)(7) – Additional Provisions

The proposed general permit contains the additional provision required for each permit. These conditions are 

found in the General Provisions of the proposed general permit.

4.4 Requirements for Sources Located in Nonattainment Areas

We did not include any additional requirements for sources locating in ozone nonattainment areas, other than 

the limits on fuel use. However, we do include ton per year emissions limitations that are lower as the 

classification of ozone nonattainment goes from marginal/moderate to serious, severe and extreme, which will 

ensure that the general permit only applies to true minor sources locating or expanding in these nonattainment 

areas.

4.5 Additional Permit Requirements

The EPA added to the general permit a 150 foot setback from the nearest property boundary and a 1,000 foot 

setback between the sawmill and the nearest residence. A setback requirement is included in the Texas permit. 
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4.6 Requirements of the Endangered Species Act and National Historic Preservation Act

Prior to seeking coverage under this general permit, sources must satisfactorily address the permitting 

requirements related to the Endangered Species Act and National Historic Preservation Act. Attached to the 

request for coverage document for the sawmill general permit, the EPA provides guidance to assist sources in

complying with these two statutes.

5. Emission Limitations1

5.1 Developing the Limitations

The draft general permit includes ton per year VOC emissions limitations that apply to sources in both 

attainment and nonattainment areas. The proposed permit does not include surrogate emissions limitation but 

instead provides the permittee the emissions factors and formulas for the source to calculate compliance with 

the emissions limitations on a monthly basis. Attachment A contains a sample calculation using VOC emission 

factors provided by the EPA. 

The tpy emission limitations used to determine eligibility for the general permit for sources located in 

attainment and nonattainment areas corresponds to the source-wide PTE at which a source would become a 

major source and subject to Title V permitting (referred to hereafter as “the Title V major source threshold”). In 

attainment areas, the Title V major source threshold is 100 tpy for any criteria pollutant, 10 tpy for a single 

hazardous air pollutant (HAP), and 25 tpy for any combination of HAPs. The Title V major source threshold in 

nonattainment areas varies by the pollutant and the nonattainment classification.

The draft permit includes the emissions limitations listed in Table 3 for sawmill plants located in attainment and 

nonattainment areas. They are set at levels intended to keep the sources emissions below the Title V major 

source thresholds (VOC is the controlling pollutant).

Table 3: Emission Limitations for Sawmill Facilities2

Pollutant of Concern Attainment Areas Nonattainment Areas

VOC 90 tpy

90 tpy (marginal and moderate ozone areas)

45 tpy (serious ozone areas)

22.5 tpy (severe ozone areas)

9 tpy (extreme ozone areas)

 

1 The definition of emission limitation used in this background document is the one provided in the Indian Country Minor 

NSR rule (described in Section 4.3) and includes requirements established by the reviewing authority that relate to the 

operation of a source, which allows for the use of production throughput limits.

2 The permit contains VOC tpy emissions limitations for kilns and surface coating operations that are slightly lower than 

these values. The emission limitations in Table 3 represent all VOC emissions expected at sawmills, which also includes 

emissions from engines and boilers.
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5.2 Emission Limitations

Three considerations form the basis for the upper eligibility emission limitations for general permits and permits 

by rule:

1. Are there any EPA regulation-based emission limitations?

2. What do actual emissions data from the 2011 National Emissions Inventory (NEI)3indicate about the size 

profile of the source category? 

3. Where do state programs establish eligibility limits? 

5.2.1 EPA Regulation-Based Emissions Limitations 

A production-based limit and tpy VOC limitations were established below the thresholds for the major NSR and 

Title V permitting programs. The emission threshold for sources located in attainment areas is 100 tpy, which is

the threshold for Title V operating permit program. The emissions thresholds for facilities located in 

nonattainment areas are set at the thresholds in Table 2 for each pollutant and nonattainment status, which 

serve as the thresholds for both the major NSR and Title V permitting programs.

In general, PM/PM10/PM2.5 and VOC are the pollutants of concern emitted by sawmills. The limits on production 

and VOC emissions ensure that all sources applying for the general permit are below the attainment and 

nonattainment area major source thresholds.

5.2.2 Analysis of NEI Data

The EPA analyzed 2011 NEI data for existing sawmill facilities across the U.S. to evaluate the emission limitations 

established in the general permit. Although the NEI does not include potential emissions information for sources 

in Indian country, it reflects the actual emissions from sawmill operations in 50 states. In order to analyze 

facilities whose emissions are similar to those for sources potentially subject to the Indian Country NSR rule, the 

EPA selected facilities for analysis with the North American Industry Classification System (NAICS) code listed in 

Table 4. For sources in the NAICS code, the EPA selected actual emissions4 within the ranges listed in Table 5. 

 Table 4: NAICS Codes Selected for Sawmill Facilities

NAICS Code Description

321113 Sawmills

 

3

For more information, go to: http://www.epa.gov/ttnchie1/net/2011inventory.html.

4 Only point source NEI data were used for this analysis. The point source inventory does not include emissions from 

nonroad engines. 
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 Table 5: Emission Ranges Selected for Sawmills Facilities

Criteria Pollutants VOC

Attainment Area

 Min. Emissions (tpy) 5

 Max. Emissions (tpy) 250

Nonattainment Area

 Min. Emissions (tpy) 1

 Max. Emissions (tpy) 250

The EPA analyzed the emissions limitations listed in Table 3 and selected the facilities with emission levels 

similar to the facilities potentially subject to the minor NSR program, i.e., the facilities with emissions greater 

than the minor NSR applicability thresholds in Table 1 of 40 CFR 49.153 (Tribal Minor NSR rule) and less than the 

Prevention of Significant Deterioration major source threshold of 250 tpy. For purposes of this analysis, facilities 

located in nonattainment areas are defined as facilities located in counties that are designated nonattainment 

for the pollutant being analyzed. 

With the NAICS code listed in Table 4 and the emission ranges defined in Table 5, the EPA identified the sawmill

facilities located in attainment and nonattainment areas for VOC. The EPA is providing the number of facilities 

(and average emissions) under the proposed emissions limitations and above the minor source thresholds. 

Table 6: Number of Facilities and Average Emissions for Sawmill Facilities Selected.

Criteria Pollutants Number of Facilities

Attainment Areas

VOC

Facilities > 5 tpy and < 90 tpy 74 (34% of facilities covered)

Average Emissions (tpy) 42

Facilities > 90 tpy and < 250 tpy 64

Average Emissions (tpy) 161

Nonattainment Areas

VOC (marginal and moderate)

Facilities >2 tpy and < 90 tpy 0 (0% of facilities covered)

Average Emissions (tpy) N/A

Facilities > 90 tpy and < 250 tpy 1

Average Emissions (tpy) 219

VOC (serious)

Facilities >2 tpy and < 45 tpy 0 (0% of facilities covered)

Average Emissions (tpy) N/A

Facilities > 45 tpy and < 250 tpy 0

Average Emissions (tpy) N/A

VOC (severe)

Facilities >2 tpy and < 22.5 tpy 0 (0% of facilities covered)

Average Emissions (tpy) N/A

Facilities > 22.5 tpy and < 250 tpy 0

Average Emissions (tpy) N/A

VOC (extreme)
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Criteria Pollutants Number of Facilities

Facilities >2 tpy and < 9 tpy 0 (0% of facilities covered)

Average Emissions (tpy) N/A

Facilities > 9 tpy and < 250 tpy 0

Average Emissions (tpy) N/A

5.2.3 State Program Limits

Table 7 shows the throughput and other limits, emission limitations and other controls required by sawmill 

permits for the two states reviewed: Oregon and Texas.

 Table 7: State Sawmill Permit Throughput Limits and Emission Limitations

State Throughput 

Limits

Criteria 

Pollutant 

Emission 

Limitations?

Engine Fuel 

or Size 

Limit?

Setback 

Required?

Fugitive 

Dust 

Controls 

Required?

PM

Emissions 

Controls 

Required?

Oregon

25,000 or 

more boardfeet/shift 

finished 

product.

PM 24 tpy; PM10

14 tpy; PM10 4.5 

tpy; 49 lbs. per 

day (MedfordAshland AQMA);

SO2 39 tpy; NOx

39 tpy; CO 99 

tpy; and VOC 39 

tpy.

Yes. No. Yes. Yes.

Texas

25 million 

board-feet per 

any 

consecutive

12-month 

period.

No. No. Yes. Yes. Yes.
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References

40 CFR 49.151 – 40 CFR 49.173, Indian Country Air Quality Planning and Management. http://www.ecfr.gov/cgibin/text-idx?tpl=/ecfrbrowse/Title40/40cfr49_main_02.tpl

40 CFR Part 60, Subpart Dc—Standards of Performance for Small Industrial-Commercial-Institutional Steam 

Generating Units. http://www.ecfr.gov/cgi-bin/textidx?SID=fe1381d2a7d4ee8c16a4aac98b6c6d29&node=40:7.0.1.1.1.12&rgn=div6

40 CFR 60 Subpart IIII – Standards of Performance for Stationary Compression Ignition Internal Combustion 

Engines. http://ecfr.gpoaccess.gov/cgi/t/text/textidx?c=ecfr&sid=f2c4f71bd50d2a8883adafec36732010&rgn=div6&view=text&node=40:6.0.1.1.1.98&idno=40

40 CFR 60 Subpart JJJJ – Standards of Performance for Stationary Spark Ignition Internal Combustion Engines.

http://ecfr.gpoaccess.gov/cgi/t/text/textidx?c=ecfr&sid=f2c4f71bd50d2a8883adafec36732010&rgn=div6&view=text&node=40:6.0.1.1.1.99&idno=40

40 CFR 63 Subpart ZZZZ – National Emission Standards for Hazardous Air Pollutants for Stationary Reciprocating 

Internal Combustion Engines. http://ecfr.gpoaccess.gov/cgi/t/text/textidx?c=ecfr&rgn=div6&view=text&node=40:13.0.1.1.1.1&idno=40

Federal Register Vol. 76, No. 127, July 1, 2011, Pages 38748-38808, “Review of New Sources and Modifications 

in Indian Country; Final Rule” (Indian Country NSR Rule). 

https://www.federalregister.gov/articles/2011/07/01/2011-14981/review-of-new-sources-and-modifications-inindian-country

Oregon Department of Environmental Quality, “General Air Contaminant Discharge Permit.”

http://www.deq.state.or.us/aq/permit/acdp/general/AQGP-010.pdf

Texas Commission on Environmental Quality, “Air Quality Standard Permit for Sawmills.”

http://www.tceq.texas.gov/permitting/air/newsourcereview/mechanical/sawmill_sp.html
Page 14 of 18

Attachment A: 

Emissions Calculations for Sawmills

Example 1: VOC Calculation for Western Hemlock with a Maximum Kiln Temperature Less than or 

Equal to 200 degrees Fahrenheit

Methodology:

 PTE (tons/year) = kiln throughput (million board feet (mbf)/hour)*VOC emission factor (lbs/mbf)*8,760 

hour/year*1 ton/2,000 lbs

Sample:

 Assume kiln throughput: 10 mbf/hour 

 VOC emission factor for western hemlock with kiln firing temperature ≤ 200° f: 0.5253 lbs/mbf

 VOC emissions (tons/year) = 10 mbf/hour*0.5253 lbs/mbf*8,760 hours/year*(1 tons/2,000 lbs)

 VOC emissions (tons/year) = 23.01 tons/year

The permittee must use the emission factors for western pine, shown in the table below, and use the 

temperature dependent factor that corresponds to the drying kiln’s temperature capability.

Species Maximum Kiln 

Temperature °F WPP1 VOC1 (lbs/mbf)

Non-Resinous Softwood Species

White Fir2

≤200 0.8388

>200 1.0902

Western Hemlock ≤200 0.5253 

>200 0.6615 

Western Red Cedar ≤200 0.3631 

>200 1.1453 

Resinous Softwood Species (Non-Pine Family)

Douglas Fir ≤200 1.1576 

>200 1.6969 

Engelmann Spruce ≤200 0.1775 

>200 0.2161 

Larch ≤200 1.1576 

>200 1.6969 

Resinous Softwood Species (Pine Family)

Lodgepole Pine ≤200 1.5293 

>200 1.5293 

Ponderosa Pine ≤200 2.3450 

>200 3.8087 

Western White Pine ≤200 2.8505 

>200 3.8087 

1 VOC emissions approximated consistent with EPA's Interim VOC Measurement Protocol for the Wood 

Products Industry - July 2007 (WPP1 VOC), http://www.epa.gov/ttnemc01/prelim/otm26.pdf. WPP1 VOC 

underestimates emissions when the mass-to-carbon ratio of unidentified VOC exceeds that of propane. 

Ethanol and acetic acid are examples of compounds that contribute to lumber drying VOC emissions (for 

some species more than others), and both have mass-to-carbon ratios exceeding that of propane.
Page 15 of 18

2White fir in this context refers to a common name for a mixture of several species of true fir grown in the 

West. This mixture includes the following species: white fir, grand fir, noble fir and subalpine fir.

Example 2: Coating Emissions

Methodology:

 VOC emissions (tons/month) = solvent usage (gallons)*density (lbs/gal)*% VOC*1 ton/2000 lbs

Sample:

 Assume: 5 gallons of coating used in a month, coating density of 5 lbs/gal, coating VOC content is 30%

 VOC emissions (tons/month) = 5 gallons*5 lbs/gal*0.30 VOC*1 ton/2000 lbs

 VOC emissions (tons/month) = 0.00375 tons/month