Iowa State Implementation Plan

for the

Regional Haze Five-Year Review 

Iowa Department of Natural Resources 

Environmental Services Division 

Air Quality Bureau 

7900 Hickman Rd Suite 1 

Windsor Heights, IA 50324 

July 9, 2013 
Table of Contents

i. Letter from Director..................................................................................................................... 3

ii. Executive Summary...................................................................................................................... 4

iii. Introduction................................................................................................................................. 5

iv. Summary of the Initial Regional Haze SIP ..................................................................................... 7

v. Federal Actions Affecting the Initial Regional Haze SIP ................................................................. 8

1. Regional Haze Periodic Reports.................................................................................................... 9

40 CFR 51.308(g)(1): Status of Measures in SIP................................................................................... 9

BART and CAIR ................................................................................................................................. 9

State Programs............................................................................................................................... 10

Federal Programs........................................................................................................................... 10

2. 40 CFR 51.308(g)(2): Emissions Reductions................................................................................ 12

3. 40 CFR 51.308(g)(3): Visibility Conditions................................................................................... 14

4. 40 CFR 51.308(g)(4): Emissions Tracking .................................................................................... 15

5. 40 CFR 51.308(g)(5): Progress Assessment................................................................................. 18

6. 40 CFR 51.308(g)(6): Assessment of Elements to Meet RPG ....................................................... 20

Electricity Generation ......................................................................................................................... 20

New Regulations................................................................................................................................. 21

Conclusions......................................................................................................................................... 22

7. 40 CFR 51.308(g)(7): Visibility Monitoring.................................................................................. 23

8. 40 CFR 51.308(h): Determination of Plan Adequacy................................................................... 24

9. Stakeholder Input ...................................................................................................................... 25

FLM Consultation................................................................................................................................ 25

Public Notice ....................................................................................................................................... 25

Appendix A. Source Apportionment Review ................................................................................... 26

Appendix B. MACT Review ............................................................................................................. 36

Appendix C. Emissions Data Compilation........................................................................................ 38

Appendix D. FLM and Public Comments.......................................................................................... 47

Comments from the USDA Forest Service.......................................................................................... 47

Comments from the National Park Service ........................................................................................ 49

Comments from EPA Region 7............................................................................................................ 50

Comments from the Minnesota Pollution Control Agency (MPCA)................................................... 50

Public Notice Documents.................................................................................................................... 52

Appendix E. Legal Authority ........................................................................................................... 55

2 

ii. Executive Summary

Congress added the national goal of preventing any future and remedying any existing impairment of 

visibility at mandatory Class I Federal areas in the 1977 Clean Air Act Amendments. The Regional Haze 

Rule (RHR) was promulgated in July 1999 (64 FR 35714, July 1, 1999) to further Congress’s national goal, 

and established regulations to eliminate manmade visibility impairment in Class I areas by 2064. 

Nationally there are 156 mandatory Class I Federal areas (Class I areas) but none are located in Iowa. 

This does not exempt Iowa from regional haze regulations as the pollutants which contribute to visibility 

impairment can be transported long distances.

Regional haze is a form of visibility impairment not directly attributable to a single source but occurs as a 

result of emissions of air pollutants from numerous sources located over a wide geographic area. The 

Regional Haze Rule and related regulations (40 CFR 51.308 and Appendix Y to Part 51) contained 

provisions that encouraged state, local, and tribal agencies to work cooperatively within regional 

planning organizations (RPOs) to address visibility impairment. Five RPOs were created for this purpose. 

Iowa was part of the Central Regional Air Planning Association (CENRAP), originally comprised of nine

states in the central U.S. 

On March 25, 2008, the Iowa Department of Natural Resources (DNR) submitted to the U.S. 

Environmental Protection Agency (EPA) a state implementation plan (SIP) for the initial period of the 

Regional Haze Rule. The DNR concluded emissions in Iowa may contribute to visibility impairment at the

Northern Midwest Class I areas, which consist of two Class I areas in Minnesota (Boundary Waters 

Canoe Area Wilderness and Voyageurs National Park) and two Class I areas in Michigan (Seney 

Wilderness Area and Isle Royale National Park). The initial regional haze SIP was developed considering 

the reasonable progress goals of the Northern Midwest Class I areas, consultation with stakeholders 

including Federal Land Managers and the states of Minnesota and Michigan, Iowa’s role in visibility 

impairment, and applicable regulations. 

Emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) from larger point sources were generally 

identified as the types of sources contributing to the average worst visibility impairment in Class I areas 

in the Midwest. Iowa’s participation in the Clean Air Interstate Rule (CAIR), a cap and trade program 

affecting larger fossil-fuel fired power plants, was a significant component of the state’s long-term 

strategy. The initial regional haze SIP also relied upon CAIR to satisfy Best Available Retrofit Technology 

(BART) requirements for electrical generating unit (EGU) SO2 and NOx emissions. A review of other 

BART eligible sources and emissions concluded that no source specific BART emissions limits were 

needed. 

Provisions of the Regional Haze Rule contained in 40 CFR 51.308(g) and (h) require that each state 

submit a progress report five years after the submittal of their initial regional haze SIP. The progress 

reports must be in the form of a SIP revision and must include a determination regarding the adequacy 

of the existing regional haze SIP. This document has been prepared to fulfill all applicable requirements

pertaining to the five year progress report of the initial regional haze SIP. The DNR concludes the 

current regional haze SIP is sufficient to address the reasonable progress goals of the Northern Midwest 

Class I areas. The DNR is also providing to EPA a negative declaration that further revision of the existing 

implementation plan is not needed at this time. This finding is based upon reductions in Iowa of 

anthropogenic NOx and SO2 emissions, the magnitude of these reductions, and existing federal 

regulations. 

4
iii. Introduction

On March 25, 2008, the Iowa Department of Natural Resources (DNR) submitted to the U.S. 

Environmental Protection Agency (EPA) a revision to Iowa’s state implementation plan (SIP) to address 

the first implementation period of the regional haze program.

1

 The Regional Haze Rule was

promulgated in July 1, 1999 (64 FR 35714) and established the first regulations governing visibility 

impairment attributable to widespread and numerous sources. Previous visibility regulations addressed

nearby sources by regulating plume blight. The Regional Haze Rule encompassed all types of sources

significantly contributing to visibility impairment. 

The Clean Air Act (CAA) provides EPA with the authority to regulate visibility impairment. In the 1977 

CAA Amendments Congress added the national goal of preventing any future and remedying any

existing impairment of visibility at mandatory Class I Federal areas. A map of the 156 mandatory Class I 

Federal areas (Class I areas) is provided in Figure 1-1. There are no Class I areas in Iowa, nor are there 

any Class I areas within 300 km of Iowa’s borders. However, the pollutants which contribute to regional 

haze can originate over diverse geographical regions and travel many hundreds of miles. While sources 

nearer to Class I areas are initially expected to be more important contributors to visibility degradation

than similar sources located further away, the regional haze regulations (see 40 CFR 51.308) cover a 

time horizon of many decades, until at least 2064, at which point manmade visibility impacts are to be

mitigated at Class I areas. Simply stated, the goals of the regional haze program are achieved when 

visibility conditions at Class I areas have returned to natural conditions. The prospective longevity and 

scope of the regional haze regulations cast a broad range of potential obligations across an extended

timeline. It is therefore possible for the requirements of the regional haze regulations to include states, 

such as Iowa, which are not near any Class I areas.

Figure 1-1. Map showing the location of the mandatory Class I Federal areas.

1 Available at: http://www.iowadnr.gov/InsideDNR/RegulatoryAir/RulesPlanning.aspx

5

 
The Regional Haze Rule called for a cooperative approach involving state, federal, and tribal participants 

to address visibility impairment. Five regional planning organizations (RPOs), shown in Figure 1-2, were 

formed to assist in the development of work products needed to understand and address visibility 

impairment. When formed the Central Regional Air Planning Association (CENRAP) included Iowa and 

eight other states (Arkansas, Kansas, Louisiana, Minnesota, Missouri, Nebraska, Oklahoma, and Texas) in 

the central portion of the U.S. 

Figure 1-2. Geographical areas of Regional Planning Organizations.

Technical analyses and interstate consultation forums provided through CENRAP and other RPOs 

assisted the DNR in the development its initial regional haze SIP. Within the initial regional haze SIP the 

DNR provided a long-term strategy to fulfill the requirement of 40 CFR 51.308(d)(3), addressed the Best 

Available Retrofit Technology (BART) regulations codified at 40 CFR 51.308(e), and satisfied the other 

applicable requirements found in 40 CFR 51.308.

The regional haze implementation process requires the submittal of a progress report five years 

following the submittal of the initial regional haze implementation plan. Progress reports are also due 

five years following all subsequent comprehensive regional haze SIP revisions. This document 

constitutes the DNR’s five-year progress report on the initial regional haze SIP. It is in the form of a SIP 

revision and fulfills all applicable obligations required by 40 CFR 51.308(g) and 51.308(h). The first 

comprehensive revision to the regional haze SIP is due July 31, 2018. 

6
iv. Summary of the Initial Regional Haze SIP

Two significant components of Iowa’s initial regional haze SIP included Best Available Retrofit 

Technology (BART) requirements and the state’s long-term strategy. A combination of federal 

equivalency determinations and local analyses were used to conclude that no BART-eligible sources in 

the state were subject to source specific BART limits. On July 6, 2005, EPA published a final rule

(Regional Haze Regulations and Guidelines for Best Available Retrofit Technology (BART) Determinations, 

70 FR 39104) which allowed electrical generating units (EGUs) participating in the cap and trade 

provisions of the Clean Air Interstate Rule (CAIR) (70 FR 25162, May 12, 2005) to serve as a substitute for 

BART for EGU NOx and SO2 emissions. The state utilized this option to satisfy most BART requirements 

associated with EGUs and also included participation in CAIR as a component of the state’s long-term 

strategy. Direct particulate matter emissions from EGUs were reviewed separately and found not to 

cause or contribute to visibly impairment at a Class I area. BART requirements for non-EGU sources 

were evaluated using a variety of analyses. The weight-of-evidence BART analysis concluded that no

non-EGU BART eligible sources were subject to BART. 

The state developed a long-term strategy to address Class I areas located outside the state which may 

be affected by emissions from Iowa, as required by 40 CFR 51.308(d)(3). Development of the long-term 

strategy and fulfillment of other regional haze obligations included consulting with downwind states 

containing Class I areas. The state participated in discussions involving Class I areas in the states of 

Missouri and Arkansas and was invited to discussions led by Oklahoma. Emissions in Iowa were 

determined not to be contributing to visibility impairment in the Class I areas in Oklahoma or to any 

Class I area in either Missouri or Arkansas.

The DNR also participated in the Northern Midwest Class I Area Consultation Group, which was

coordinated by the states of Minnesota and Michigan. Two Class I areas are located in Minnesota, the 

Boundary Waters Canoe Area Wilderness (BOWA) and Voyagers National Park (VOYA). Michigan also 

contains two Class I areas, Isle Royale National Park (ISLE) and Seney Wilderness Area (SENE). 

Collectively these four class I areas are referred to as the Northern Midwest Class I areas. 

Photochemical modeling conducted by CENRAP, using particulate matter source apportionment (PSAT) 

techniques, indicated approximately 4-5% of the total modeled visibility impairment in both 2002 and 

2018 in each of the four Northern Midwest Class I areas was associated with emissions in Iowa. These

limited contributions were primarily attributable to SO2 and NOx emissions from elevated point sources. 

A review of the source apportionment results is provided in Appendix A for convenience. 

The DNR concluded emissions in Iowa may contribute to visibility impairment at the Northern Midwest 

Class I areas. Iowa’s long-term strategy relied upon a combination of existing state and federal 

regulations to achieve a ‘fair share’ of emissions reductions necessary to meet the reasonable progress 

goal (RPG) established for each Northern Midwest Class I area. On-going emission control programs 

considered in the long-term strategy included, for example, the state’s minor and major new source 

review (NSR) programs, and measures mitigating the impacts of construction activities. Federal 

programs considered in development of the long-term strategy included the 2007 heavy-duty highway 

diesel rule, Tier 2 vehicle and gasoline sulfur program, clean air nonroad diesel rule, pertinent new 

source performance standards (NSPS), national emissions standards for hazardous air pollutants 

(NESHAP) and associated maximum achievable control technology (MACT) standards, and CAIR. These 

lists are not exhaustive but compromise the substantial components of the long-term strategy. A 

comprehensive discussion of the long-term strategy can be found in the initial regional haze SIP.

7
v. Federal Actions Affecting the Initial Regional Haze SIP

On December 23, 2008, roughly nine months after the DNR submitted the initial regional haze SIP, the 

U.S. Court of Appeals for the District of Columbia (DC Circuit Court of Appeals) issued a ruling remanding 

CAIR. The remand left CAIR in place while directing EPA to development a replacement rule. The 

Court’s ruling was significant to Iowa’s regional haze SIP as CAIR was used to satisfy the BART 

requirements related to SO2 and NOx emissions from EGUs and was also relied upon as a component of 

the state’s long-term strategy. 

During the interim period when CAIR remained in place, while a replacement rule was being developed, 

EPA did not take action on the state’s regional haze SIP. On August 8, 2011 (76 FR 48208), the final rule 

“Federal Implementation Plans: Interstate Transport of Fine Particulate Matter and Ozone and 

Correction of SIP Approvals” was promulgated as the CAIR replace rule. This rule, commonly referred to 

as the Cross State Air Pollution Rule (CSAPR), also used a cap-and-trade approach to reduce emissions of 

NOx and SO2 from EGUs in the (mostly) eastern portions of the U.S. 

On November 9, 2011, EPA agreed to a schedule for taking action on 45 regional haze SIPS. The final 

Consent Decree required EPA to propose action on Iowa’s regional haze SIP by February 15, 2012, and 

take final action by June 15, 2012. On June 7, 2012 (77 FR 33642) EPA published a final rule providing 

limited disapproval of Iowa’s (and many other state’s) regional haze SIP. The limited disapproval applied 

only to those portions of the regional haze SIP tied to (the remand of) CAIR; EPA disapproved the state’s 

use of CAIR as a substitute for BART for NOx and SO2 emissions from EGUs, and the use of CAIR in the 

long-term strategy. 

In the same final rule (77 FR 3364, June 7, 2012) EPA promulgated a Federal Implementation Plan (FIP) 

for Iowa which addressed the portions of the regional haze SIP disapproved for their reliance upon CAIR. 

The FIP essentially substituted CSAPR in lieu of CAIR in the long-term strategy and to satisfy EGU BART 

obligations related to NOx and SO2 emissions. On June 26, 2012 (77 FR 38006), EPA finalized a limited 

approval of Iowa’s SIP for all other regional haze elements not addressed in the June 7, 2012 action. The 

final rule approved the BART determinations for non-EGUs and EGU direct particulate matter emissions,

and components of the long-term strategy not associated with CAIR.

On August 21, 2012, a three judge panel of the DC Circuit Court of Appeals issued a 2-1 ruling which 

vacated CSAPR and remanded the rule to EPA, while leaving CAIR in place until supplanted. On October 

5, 2012, EPA filed a petition with the U.S. Circuit Court of Appeals for the DC Circuit for a rehearing en 

banc of the court’s August 21, 2012, CSAPR decision. Three additional petitions for rehearing were also 

filed by other parties. On January 24, 2013, the D.C. Circuit Court of Appeals denied all petitions for 

rehearing en banc. Consequently the CSAPR vacature currently stands and CAIR continues to remain in 

effect. Despite the litigation and the ongoing uncertainty associated with the appeal to the U.S. 

Supreme Court, the DNR is still required to submit a five-year progress report on the initial regional haze 

SIP. 

8
1. Regional Haze Periodic Reports

The general purpose of the five-year review is to evaluate progress towards the reasonable progress 

goals of each mandatory Class I Federal area (Class I area) which may be affected by emissions from

within the State. The progress reports are periodic in that they are due five years following the 

submission of the initial regional haze SIP and every five years following submission of a comprehensive 

regional haze SIP revision. The progress report must be in the form of an implementation plan revision 

that complies with the procedural requirements of 40 CFR 51.102 and 51.103. The regulatory criteria 

for the progress reports are codified in 40 CFR 51.308(g) and (h). While Iowa does not contain a Class I 

area, this reduces but does not eliminate the applicable requirements. The specific elements which 

must be addressed in the five-year progress report for a state without a Class I area are addressed 

throughout the remainder of this document. 

40 CFR 51.308(g)(1): Status of Measures in SIP

40 CFR 51.308(g)(1) requires that the five-year periodic report contain: “A description of the status of 

implementation of all measures included in the implementation plan for achieving reasonable progress 

goals for mandatory Class I Federal areas both within and outside the State.”

Long-term strategies developed for the initial regional haze SIPs were to include all measures relied 

upon by a state to achieve the reasonable progress goals of Class I areas affected by their emissions. 

Iowa’s long-term strategy was broad in scope to ensure it encompassed all ongoing state and federal 

programs reducing the types of air pollutants that might be associated with visibility impairment. 

Additional factors listed in 40 CFR 51.308(d)(3)(v) such as smoke management plans, source retirements

and replacements, emissions limits, and the net effect upon visibility from projected changes in 

emissions from anthropogenic emissions over the period addressed by the long-term strategy, were also 

required components of the long-term strategy. Not all items included in Iowa’s long-term strategy are 

expected to significantly influence visibility impairment in a Class I area but were included for 

completeness. A review of all applicable measures either specifically2 identified by the regional haze 

regulations or of greatest relevance to the reasonable progress goals of the Northern Midwest Class I 

areas is provided below.

3

 

BART and CAIR

Compliance with the BART requirements for NOx and SO2 emissions from EGUs was sought through 

participation in CAIR. Participation in the CAIR cap and trade program was also a significant component 

of the state’s long-term strategy and was expected to yield EGU NOx emissions reductions and 

moderate, if not reduce, SO2 emissions. While CAIR was remanded by the DC Circuit Court of Appeals, 

as previously discussed the CAIR rule remains in effect and sources in Iowa continue to comply with the 

state (see 567 Iowa Administrative Code Chapter 34) and federal requirements associated with CAIR. 

No non-EGU BART sources were found to be BART eligible and therefore no BART specific emissions 

limits were developed.

2 Such as the requirement that long-term strategies must consider measures to mitigate emissions from 

construction activities (51.308(d)(3)(v)(B)) and smoke management plans (51.308(d)(3)(v)(E)). 3 Not all measures reviewed are considered significant in terms of visibility impairment, but are once again 

included for completeness.

9

 
State Programs

No source specific or unit specific emissions limits or compliance schedules were developed for the 

regional haze SIP. The DNR continues to implement a major source Prevention of Significant 

Deterioration (PSD) permitting program and a minor source review program. The DNR’s rules on 

fugitive dust (567 IAC 23.3(2)“c”), which apply to construction activities, continue to require that 

reasonable precautions shall be taken to prevent the discharge of visible emissions of airborne dust 

beyond the lot line of the property from which the emissions originate. 

The DNR has developed a prescribed fire policy to address how the DNR conducts prescribed burning on 

state, federal, and private lands for which the agency has management authority. The fire policy 

addresses smoke monitoring and minimizing the impacts from smoke and requires a smoke 

management plan. However, Iowa currently burns less than approximately 30,000 acres per year on 

average, which is considerably less than most other states, and fires in Iowa were not identified as 

contributing to visibility impairment in Class I areas. Within the context of the Regional Haze Rule

changes in emissions resulting from smoke management plans for prescribed fires in Iowa are not 

significant and are expected to have no discernible impact on visibility impairment in Class I areas.

Federal Programs4

The emission reductions associated with the federal programs that are described by the following

paragraphs were included in the CENRAP future year emissions estimates. Descriptions contain

qualitative assessments of emissions reductions associated with each program, and where possible, 

quantitative assessments. A discussion of Maximum Achievable Control Technology (MACT) standards is 

provided in Appendix B.

2007 Heavy-Duty Highway Rule (40 CFR Part 86, Subpart P)

In this regulation EPA set a particulate matter (PM) emissions standard for new heavy-duty engines of 

0.01 g/bhp-hr, which took full effect for diesel engines in the 2007 model year. This rule also included 

standards for NOx and non-methane hydrocarbons (NMHC) of 0.20 g/bhp-hr and 0.14 g/bhp-hr, 

respectively. These diesel engine NOx and NMHC standards were successfully phased in together 

between 2007 and 2010. The rule also required that sulfur in diesel fuel be reduced to facilitate the use 

of modern pollution-control technology on these trucks and buses. The EPA required a 97 percent 

reduction in the sulfur content of highway diesel fuel -- from levels of 500 ppm (low sulfur diesel) to 15 

ppm (ultra-low sulfur diesel). These requirements were successfully implemented on the timeline in the 

regulation. 

Tier 2 Vehicle and Gasoline Sulfur Program (40 CFR Part 80, Subpart H; 40 CFR Part 85; 40 CFR Part 86)

The EPA’s Tier 2 fleet averaging program for onroad vehicles, modeled after the California LEV ( Low 

Emissions Vehicle) II standards, became effective in the 2005 model year. The Tier 2 program allows 

manufacturers to produce vehicles with emissions ranging from relatively dirty to very clean, but the mix 

of vehicles a manufacturer sells each year must have average NOx emissions below a specified value. 

Mobile emissions continue to benefit from this program as motorists replace older, more polluting 

vehicles with cleaner vehicles.

4 The majority of the text for this section courtesy of the South Carolina Department of Health and Environmental 

Control, “Regional Haze State Implementation Plan Periodic Report,” December 28, 2012.

10

 
Clean Air Nonroad Diesel Rule (40 CFR 89; 40 CFR 1039)

The EPA adopted standards for emissions of NOx, hydrocarbons, and carbon monoxide from several 

groups of nonroad engines, including industrial spark-ignition engines and recreational nonroad 

vehicles. Industrial spark-ignition engines power commercial and industrial applications and include 

forklifts, electric generators, airport baggage transport vehicles, and a variety of farm and construction

applications. Nonroad recreational vehicles include snowmobiles, off-highway motorcycles, and allterrain vehicles. These rules were initially effective in 2004 and were fully phased in by 2012.

The nonroad diesel rule set standards that reduced emissions by more than 90 percent from nonroad 

diesel equipment and, beginning in 2007, the rule reduced fuel sulfur levels by 99 percent from previous 

levels. The reduction in fuel sulfur levels applied to most nonroad diesel fuel in 2010 and applied to fuel 

used in locomotives and marine vessels in 2012. 

11
2. 40 CFR 51.308(g)(2): Emissions Reductions

40 CFR 51.308(g)(2) requires: “A summary of the emissions reductions achieved throughout the State 

through implementation of the measures described in paragraph (g)(1) of this section.”

The requirements of 51.308(g)(2) are best met quantitatively by a review of changes in NOx and SO2 

emissions from EGUs.

5

 The CAIR rule encompasses significant aspects of the state’s initial regional haze 

SIP.6

 Emissions of SO2 and NOx from elevated point sources are responsible for most visibility 

impairment attributable to Iowa at the Northern Midwest Class I areas on the 20% worst impaired days 

(see Appendix A); and based upon an emissions inventory review of the 2008 NEI (version 2), most point 

source NOx and SO2 emissions in Iowa are associated with EGUs (see Chapter 4). 

Emissions data for EGUs affected by CAIR were obtained from EPA’s Clean Air Markets Division (CAMD) 

air markets program data website (http://ampd.epa.gov/ampd/). Annual EGU SO2 and NOx emissions

in Iowa for 2002, 2008, and 2011 are shown in Table 2-1 and compared with the 2018 projections from 

the Integrated Planning Model (IPM) utilized in the initial regional haze SIP. The units are in tons7 per 

year.

Table 2-1. Actual annual SO2 and NOx emissions in tons per year for 2002, 2008, and 2011 from all 

EGU units reporting to CAMD, and projected 2018 EGU emissions from the initial regional haze SIP.

2002

Emissions

2008

Emissions

2011

Emissions

2018

Projections

SO2 127,847 109,293 95,946 151,354

NOx 78,956 49,023 38,574 65,629

The IPM projections for 2018 include increases in EGU SO2 emissions (23,507 tons) and decreases in 

EGU NOx emissions (-13,327 tons) across the 2002 to 2018 planning period. Interpreting these 

predictions in the context of CAIR it appears that IPM concluded more sources in Iowa would choose to 

purchase SO2 allowances rather than reduce emissions, while modest NOx controls would be added. 

Between 2002 and 2008 EGU SO2 and NOx emissions reported to CAMD declined by 18,554 and 29,933 

tons, respectively. Table 2-1 shows that in 2011 SO2 and NOx emissions continued to decline and were 

below the 2002 levels by 31,901 and 40,382 tons, respectively, which represent decreases of 25% and 

51%. 

The 2011 actual SO2 and NOx EGU emissions were significantly below the projected 2018 values, by 

55,408 and 27,055 respectively, which represents SO2 and NOx emissions that are 37% and 41% below 

their 2018 projections. Figure 2-1 shows that decreases in NOx and SO2 emissions between the 2002 

5 Accurately calculating the emissions reductions from many of the state and federal measures mentioned in 

Chapter 1 requires data not routinely collected. Qualitatively, the continued implementation of those federal and 

state measures not affecting point sources are expected to reduce emissions, including NOx and SO2 emissions. 6 As discussed previously CAIR is relied upon to satisfy most BART requirements for BART-eligible EGUs and is a 

significant component of the long-term strategy. 7 All tonnage values in this report use short tons.

12

 
baseyear and 2011 have occurred while actual heat input has increased, indicating the reductions reflect

cleaner generation and not merely decreased demand. 

Figure 2-1. Actual annual emissions of SO2 and NOx and heat input (in 1000 MMBtu) in 2002, 2008, 

and 2011 as reported to CAMD (includes all units reporting to CAMD), and projected 2018 emissions.

13
3. 40 CFR 51.308(g)(3): Visibility Conditions

The requirements of 40 CFR 51.308(g)(3) relate to assessments of visibility conditions and apply only to 

states that contain Class I areas.

14
4. 40 CFR 51.308(g)(4): Emissions Tracking

40 CFR 51.308(g)(4) requires: “An analysis tracking the change over the past 5 years in emissions of 

pollutants contributing to visibility impairment from all sources and activities within the State. Emissions 

changes should be identified by type of source or activity. The analysis must be based on the most recent 

updated emissions inventory, with estimates projected forward as necessary and appropriate, to account 

for emissions changes during the applicable 5-year period.”

A statewide emissions inventory of pollutants that are reasonably anticipated to cause, or contribute to, 

visibility impairment in any Class I area was required to be included in the initial regional haze SIP (40 

CFR 51.308(d)(4)(v)). While not all emissions in Iowa contribute to visibility impairment at a Class I area, 

Iowa chose to comply with this requirement by including a complete statewide inventory containing 

emission rates for all anthropogenic and biogenic sources.

8

 

The initial regional haze SIP used a baseline year of 2002 (see Chapter 7 of the initial regional haze SIP). 

The 2002 point source inventory was derived from the 2002 NEI and state-specific updates. The 

remaining source categories were developed from a variety of data sources and inventory development 

techniques. Emissions were classified into ten source categories: ammonia, area, fugitive dust, offroad, 

onroad, point EGU, point non-EGU, road dust, fires, and biogenic. A detailed description of these ten 

source categories can be found in Appendix C. The species considered were: volatile organic 

compounds (VOC), nitrogen oxides9 (NOx), fine particulate matter (PM2.5), coarse particulate matter 

(PM10), ammonia (NH3), and sulfur dioxide (SO2). 

All species and source types summarized in the initial regional haze SIP are reviewed in this five-year 

progress report. A comprehensive emissions review is provided to be consistent with the initial regional 

haze SIP. The most recent comprehensive inventory is the 2008 National Emissions Inventory (NEI), 

version 2 (version dated April 10, 2012)10, or simply the 2008 NEIv2. The 2008 inventory offers a recent 

and nationally uniform platform for emissions comparisons and is the logical data source to meet the 

requirements of 40 CFR 51.308(g)(4). While technically providing a six, and not five year time horizon

from the original SIP’s baseline inventory, the 2008 NEIv2 does not require any forward projections to 

fulfill the obligations of 40 CFR 51.308(g)(4). 

A summary of the 2002 inventory from the initial regional haze SIP is provided in Table 4-1.

11 Table 4-2

provides a summary of 2008 NEIv2 inventory data. All units are tons per year. The biogenic source 

category is not included in the subtotals to focus on anthropogenic emissions. Differences between the 

2002 and 2008 inventories are summarized in Table 4-3, with positive values representing emissions 

growth from 2002 to 2008. Note that the 2008 NEIv2 data have been categorized using methods to help 

ensure the comparison with the 2002 data is consistent. Additional details on the 2008 NEIv2 data 

categorization process are provided in Appendix C.

8 In the Midwest point source emissions of NOx and SO2 are often more closely evaluated in the context of 

regional haze.

9 NOx is defined as the sum of NO2 and NO, this definition is used throughout this document.

10 All 2008 NEI emissions data included in this report are associated with version 2 of the 2008 NEI, version dated 

April 10, 2012. For simplicity, this version will be referred to as the 2008 NEIv2.

11 For reference the data is that reported in Table 7.1 of the initial regional haze SIP, available at 

http://www.iowadnr.gov/InsideDNR/RegulatoryAir/RulesPlanning.aspx.

15

 
Table 4-1. Summary of Iowa emissions for the 2002 baseline year (tons).

Category VOC NOx PM2.5 PM10 NH3 SO2

Ammonia 0 0 0 0 258,915 0

Area 106,712 6,782 11,540 12,182 6,560 3,184

Fugitive Dust a 0 0 38,666 193,331 0 0

Offroad 63,694 92,595 8,904 9,707 79 9,037

Onroad 87,392 120,621 1,747 2,373 3,064 3,200

Point EGU 1,075 81,761 4,527 9,424 0 135,833

Point Non-EGU 41,184 35,812 7,651 17,495 3,317 51,836

Road Dust a 0 0 19,525 127,882 0 0

Fires b 1,670 200 5,493 5,817 48 203

Subtotal 301,727 337,771 98,053 378,211 271,983 203,293

Biogenic 408,291 25,732 0 0 0 0 a Fugitive dust and road dust emission rates reflect what remains after the application of transport factors. b Represents the sum of the 2002 ‘Area Fire,’ Point Fire,’ and ‘Wildfire’ categories.

Table 4-2. Summary of Iowa emissions from the 2008 NEIv2 (tons).

Category VOC NOx PM2.5 PM10 NH3 SO2

Ammonia 0 0 0 0 295,549 0

Area 68,399 5,163 6,967 7,288 892 2,155

Fugitive Dust a 0 0 70,238 365,960 0 0

Offroad 38,837 85,831 5,918 6,228 65 1,481

Onroad 41,293 90,630 3,666 4,234 1,515 1,229

Point EGU 686 51,347 6,007 8,586 31 117,692

Point Non-EGU 21,480 35,933 5,357 8,372 3,387 43,166

Road Dust a 0 0 17,354 147,591 0 0

Fires 4,361 758 2,865 3,099 237 189

Subtotal 175,055 269,662 118,371 551,358 301,676 165,913

Biogenic 289,743 35,620 0 0 0 0 a Transport factors were not applied to the 2008 fugitive dust or road dust emissions.

Table 4-3. Changes in emissions from 2002 to 2008 (tons). Positive values indicate growth.

Category VOC NOx PM2.5 PM10 NH3 SO2

Ammonia 36,634

Area -38,313 -1,619 -4,573 -4,894 -5,668 -1,029

Fugitive Dust a 31,572 172,629

Offroad -24,857 -6,764 -2,986 -3,479 -14 -7,556

Onroad -46,099 -29,991 1,919 1,861 -1,549 -1,971

Point EGU -389 -30,414 1,480 -838 31 -18,141

Point Non-EGU -19,704 121 -2,294 -9,123 70 -8,670

Road Dust a -2,171 19,709

Fires 2,691 558 -2,628 -2,718 189 -14

Subtotal -126,672 -68,109 20,318 173,147 29,693 -37,380

Biogenic -118,548 9,888 a

Apparent increases in PM10 and PM2.5 emissions from the fugitive dust and road dust categories are 

predominantly, if not wholly, attributable to the 2008 emissions not being reduced by transport factors.

16
Iowa’s emissions of anthropogenic SO2 and NOx, which may contribute to visibility impairment at the 

Northern Midwest Class I areas, decreased by 37,380 and 68,109 tons, respectively, from 2002 to 2008. 

Restated as a percentage the SO2 and NOx decreases between 2002 and 2008 represent reductions of

18.4 and 20.2%, respectively. The NOx emissions reductions are predominantly associated with offroad 

and onroad12 sources (potentially a result of ongoing federal programs) and point EGU sources. Sulfur 

dioxide emissions have declined from all applicable categories, with nearly half the total SO2 emissions 

reductions attributed to point source EGU emissions. Reductions from non-EGU point sources and 

offroad sources account for most of the remaining SO2 reductions. A significant decrease in total 

anthropogenic VOC emissions of 126,672 tons (40%) is estimated to have occurred between the 2002 

and 2008 emissions inventories, associated with reductions from nearly all sectors. 

Total anthropogenic PM2.5 and PM10 emissions show increases of 20,318 and 173,147 tons per year,

respectively, between 2002 and 2008. These increases are driven almost entirely by the fugitive dust 

category, and to a lesser extent the road dust sector for PM10 emissions. It is imperative to note that 

the 2002 fugitive dust and road dust emissions estimates provided in Table 4-1 represent the values that 

remain after the application of transport factors, while the 2008 data (see Table 4-2) have not been 

similarly adjusted. Transport factors are reductions applied to fugitive dust and road dust emissions to 

account for the removal of particles near their emission source by vegetation and surface features, a 

removal mechanism that photochemical grid models do not accurately capture. The near-source 

capture transport factors were based on county-level vegetative cover and were applied to the 2002 

raw fugitive dust and road dust inventories to prepare them for input to the air quality models used in 

development of the initial regional haze SIP. 

The transport factors used in the 2002 data inventory were applied within the emissions modeling 

system and are not readily available. While the transport factor discrepancy does not permit a precise 

comparison of the 2002 and 2008 fugitive and road dust emissions, a crude evaluation is possible

assuming a simple 50% reduction of the 2008 fugitive dust and road dust emissions as a surrogate for

the application of county-level transport factors. This simple reduction would bring the 2008 PM2.5 and 

PM10 fugitive and road dust13 emissions in line and generally below the 2002 values. Regardless of the 

actual differences between the 2002 and 2008 fugitive dust and road dust emissions, such emissions

from Iowa are not known to contribute significantly to visibility impairment at Class I areas, and soil 

impacts at IMPROVE monitors are likely mainly due to local dust sources.

14

12 A meaningful comparison between the CENRAP 2002/2018 and the 2008 NEI on road emissions is complicated 

by the significantly different methods used to estimate onroad emissions. The 2002/2018 data are based upon use 

of the MOBILE6 model while the 2008 NEI are derived from EPA’s application of the new Motor Vehicle Emissions 

Simulator (MOVES) mobile source model. The extent to which the different methodologies influence the change in 

emissions is not readily quantifiable but could be significant. However, this discrepancy does not influence other 

source sector emissions and does not alter any substantive conclusions.

13 While the PM2.5 road dust emissions are lower in 2008 than 2002, despite the 2002 data being reduced by the 

application of the transport factors, it is not known if these changes represent real-world modification or are 

simply the result of changes in the methods used to estimate emissions from this source category. 14 Environ International Corporation (ENVIRON), September 12, 2007. Technical Support Document for CENRAP 

Emissions and Air Quality Modeling to Support Regional Haze State Implementation Plans. Prepared for the 

Central Regional Air Planning Association. (Appendix 7.1 of the initial regional haze SIP.)

17

 
5. 40 CFR 51.308(g)(5): Progress Assessment

40 CFR 51.308(g)(5) requires: “An assessment of any significant changes in anthropogenic emissions 

within or outside the State that have occurred over the past 5 years that have limited or impeded 

progress in reducing pollutant emissions and improving visibility.” 

The 2018 emissions projections from the initial regional haze SIP are provided in Table 5-1.

15 Table 5-2

provides the differences between the 2018 projections and the 2008 NEIv2 summary (Table 4-2).

Negative values in Table 5-2 indicate the 2008 NEIv2 emissions estimates are below the 2018 

projections. Figure 5-1 provides a graphical representation of the anthropogenic emissions for 2002,

2008, and the projected 2018 inventory.

Table 5-1. Summary of Iowa emissions projected to 2018 (tons).

Category VOC NOx PM2.5 PM10 NH3 SO2

Ammonia 0 0 0 0 302,012 0

Area 127,849 7,476 10,677 11,510 13,304 3,224

Fugitive dust a 0 0 40,608 203,044 0 0

Offroad 37,143 60,210 5,582 6,088 101 220

Onroad 36,404 33,975 708 708 4,225 400

Point EGU 1,802 65,629 9,578 11,232 713 151,354 b

Point Non-EGU 56,714 40,964 10,151 21,737 5,763 42,862

Road dust a 0 0 17,712 114,889 0 0

Fires 1,672 200 5,495 5,819 49 204

TOTAL 261,584 208,454 100,511 375,027 326,167 198,264

Biogenic 408,291 25,732 0 0 0 0 a

The 2018 fugitive dust and road dust emissions were adjusted by the 2002 transport factors. b

Reflects use of the “Modified” SO2 value from Table 7.2 of the initial regional haze SIP.

Table 5-2. Differences in emissions between the 2008 NEIv2 data and 2018 projections (tons).

a

 

Category VOC NOx PM2.5 PM10 NH3 SO2

Ammonia 0 0 0 0 -6,463 0

Area -59,450 -2,313 -3,710 -4,222 -12,412 -1,069

Fugitive Dust b 0 0 29,630 162,916 0 0

Offroad 1,694 25,621 336 140 -36 1,261

Onroad 4,889 56,655 2,958 3,526 -2,710 829

Point EGU -1,116 -14,282 -3,571 -2,646 -682 -33,662

Point Non-EGU -35,234 -5,031 -4,794 -13,365 -2,376 304

Road Dust b 0 0 -358 32,702 0 0

Fires 2,689 558 -2,630 -2,720 188 -15

TOTAL -86,529 61,208 17,860 176,331 -24,491 -32,351

Biogenic -118,548 9,888 0 0 0 0 a Negative values indicate the 2008 emissions are lower than 2018 projections. b The 2008 fugitive dust and road dust emissions estimates were not reduced by a transport factor. 

Apparent increases in PM10 and PM2.5 emissions from these categories are predominantly, if not wholly, 

attributable to this inconsistency.

15 From Table 7.2 of the initial regional haze SIP.

18

 
Figure 5-1. Comparison of Iowa’s actual emissions for 2002 and 2008, and the 2018 projections. (For 

reference and convenience the data in this chart have been consolidated into a table in Appendix C.)

Total anthropogenic SO2 emissions in 2008 were below 2018 projections by 32,351 tons. Between 2002 

and 2018 total anthropogenic NOx emission reductions of 129,317 tons were forecast. According to the 

2008 NEIv2, over half this reduction has already been achieved (68,109 tons, see Table 4-3). While NH3 

emissions increases were estimated to be about 14% between 2002 and 2008, the increase does not 

exceed the 2018 forecast. It is not known if the NH3 increase is a reasonable representation of actual 

emissions increases between 2002 and 2008 or is computational in nature—the result of using different 

versions of and inputs to the Carnegie Mellon University (CMU) NH3 emissions model. The 2008 

estimate appears reasonable in comparison to the 2002 and 2018 data and further review of the 

ammonia emissions estimates is currently not warranted. At this time VOC emissions have not been 

widely targeted for reductions in the context of regional haze SIPs, however it may be of interest to note 

total VOC emissions were significantly lower in 2008 than the 2018 projections, by 86,529 tons. 

Total PM2.5 and PM10 emissions are noticeably higher in 2008 than either the 2002 or projected 2018 

emissions. This apparent increase is not impeding progress in reducing pollutant emissions as it is 

mostly, if not completely, an artifact of the transport factor discrepancy discussed above.16 Many other 

2008 PM2.5 and PM10 source category emissions estimates are below the 2018 projections.

In summary, emissions reductions in 2008 were generally ahead of schedule or greater than the 2018

projections. No changes in anthropogenic emissions within the state have occurred that have limited or 

impeded progress in reducing pollutant emissions and improving visibility. 

16 To summarize, the 2002 and 2018 PM2.5 and PM10 fugitive dust and road dust emissions were reduced by a 

transport factor (which, for example, may be on the order of a 50% reduction) while the 2008 data were not 

similarly adjusted.

19

 
6. 40 CFR 51.308(g)(6): Assessment of Elements to Meet RPG

40 CFR 51.308(g)(6) requires: “An assessment of whether the current implementation plan elements and 

strategies are sufficient to enable the State, or other States with mandatory Federal Class I areas 

affected by emissions from the State, to meet all established reasonable progress goals.”

In the initial regional haze SIP the DNR concluded emissions in Iowa may contribute to visibility 

impairment at the Northern Midwest Class I areas, which consist of two Class I areas in Minnesota 

(Boundary Waters Canoe Area Wilderness and Voyageurs National Park) and two Class I areas in 

Michigan (Seney Wilderness Area and Isle Royale National Park).

According to photochemical source apportionment modeling conducted for the initial regional haze SIP 

(Appendix A) Iowa’s visibility impacts in the Northern Midwest Class I areas were primarily associated 

with elevated point source SO2 and NOx emissions. Elevated point source emissions are split among

two categories in the inventory, EGUs and non-EGUs. Based upon the 2002 and 2008 actual emissions 

data, about 70% of the elevated point source SO2 emissions are associated with EGUs, with the 

remainder from non-EGUs. For elevated point source NOx emissions, about 60-70% are associated with 

EGUs, with the remainder again associated with non-EGUs. It can be inferred that any significant 

changes in EGU emissions will inform whether the current implementation plan is sufficient to meet the 

reasonable progress goals of the Northern Midwest Class I areas.

Electricity Generation

Based upon the emissions data discussed previously it was shown Iowa’s 2011 EGU SO2 and NOx 

emissions are substantially lower than projected 2018 EGU emissions, by 55,408 and 27,055 tons, 

respectively. A brief review of the recent 2012 Iowa specific CAMD data (not shown) indicates NOx and 

SO2 emissions have continued to decline. Despite uncertainty that exists regarding the future of CAIR 

and any potential replacement rules, the declines are not entirely unexpected.

CAIR will continue to be implemented in Iowa until supplanted, but its importance for influencing EGU 

SO2 and NOx emission reductions appears diminished. A significant or prolonged upswing in SO2 and 

NOx emissions from the electrical generating sector is not anticipated before a comprehensive regional 

haze SIP revision is required (by July 31, 2018). This assumption is supported by projections of electricity 

generation from coal and natural gas provided in the 2012 Annual Energy Outlook (AEO) reference case 

developed by the U.S. Energy Information Agency.17 Figure 6-1 shows that coal use for purposes of 

electricity generation is predicted to continue decreasing nationwide beyond 2011 through 2016. The 

decrease in coal use largely occurs as a result of an increasing reliance upon natural gas usage for 

electricity generation. Decreases in NOx and SO2 emissions from EGUs are expected to accompany 

these trends. While the trends change slightly after 2015, coal usage remains well below recent levels. 

This information provides a national perspective that should represent likely patterns within the state of 

Iowa.

17 http://www.eia.gov/forecasts/aeo/er/index.cfm

20

 
Figure 6-1. Nationwide projected net coal and natural gas electricity generation supply. Includes 

plants that only produce electricity for sale and combined heat and power plants whose primary 

business is to sell electricity and heat to the public.

Although NOx and SO2 emissions estimates for all non-EGU source categories (including point non-EGU, 

area, offroad, onroad, etc.) were not readily available for 2011, emissions increases between 2008 and 

2011 from non-EGU sources which could significantly offset reductions from the EGU sector are not 

expected. This assessment is based upon the magnitude of the EGU reductions, declining emissions 

trends between 2002 and 2008 from other source sectors, and ongoing implementation of federal and 

state regulations.

New Regulations

Since the development of the state’s initial regional haze SIP EPA has promulgated standards which are 

anticipated to yield new emissions reductions. Based upon the 2008 NEIv2, total anthropogenic SO2 

emissions have already declined ahead of the 2018 projections by 32,351 tons. Total anthropogenic 

NOx emissions in 2008 were 68,109 tons below the 2002 baseyear, achieving 53% of the 129,317 tons of 

NOx emissions projected to occur over the 16-year timeframe between 2002 and 2018. The following 

new regulations have the potential to further reduce emissions associated with visibility impairment in 

the Northern Midwest Class I areas.18 

Mercury and Air Toxics Standard (MATS)

On December 16, 2011, the EPA signed a rule to reduce emissions of toxic air pollutants from power 

plants. Specifically, the mercury and air toxics standards for power plants will reduce emissions from 

new and existing coal and oil-fired electric utility steam generating units. The final rule establishes 

power plant emission standards for mercury, acid gases, and non-mercury metallic toxic pollutants. EPA 

18 Quantitatively evaluating the relationships between the new regulations, subsequent emissions reductions in 

Iowa, and any related visibility improvement within the Northern Midwest Class I areas is beyond the scope of the 

five-year review. Additionally, the DNR is currently not relying upon the new regulations as a source of emissions 

reductions necessary to meet regional haze obligations.

21

 
estimates MATS will reduce acid gas emissions by 88% from power plants, and is also expected to 

reduce SO2 emissions.

Portland Cement Air Toxics Standards

On December 20, 2012, EPA signed the final amendments to the air toxics rules for Portland cement 

manufacturing. The amended rule will maintain dramatic reductions of acid gases, particulate matter,

and total hydrocarbons from existing cement kilns across the country, while ensuring that emissions 

from new kilns remain low. Existing kilns must comply with the standards by Sept. 9, 2015, and if 

needed, may request an additional year. Nationwide EPA anticipates the rule will reduce hydrochloric 

acid emissions by 96 percent, particulate matter by 91 percent, and total hydrocarbons by 82 percent. 

National Ambient Air Quality Standards (NAAQS)

On January 22, 2010, EPA strengthened the health-based NAAQS for NO2, establishing a new 1-hour 

standard at a level of 100 ppb. On January 20, 2012 EPA designated all areas of the country as 

“unclassifiable/attainment” for the 2010 NO2 NAAQS.

On June 3, 2010, the EPA promulgated a new 1-hour SO2 standard at a level of 75 ppb. Areas not 

meeting the standard are expected to be designated nonattainment in the June 2013 timeframe. Within 

18 months of a nonattainment designation states are required to submit a plan demonstrating

compliance (as expeditiously as practicable) with the standards. 

On December 14, 2012, EPA strengthened the PM2.5 NAAQS, reducing the level of the annual standard 

from 15 μg/m3 to 12 μg/m3

. EPA is expected to finalize designations by December 14, 2014. Projections 

provided by EPA suggest 99% of counties with monitors will meet the revised standard by 2020.

19

Conclusions

Substantial EGU SO2 and NOx emissions reductions have occurred that were not anticipated in the initial 

regional haze SIP. Total anthropogenic NOx and SO2 emissions have also declined significantly since 

2002. Offsetting future increases are not anticipated based upon existing regulations and current

market forces. These factors demonstrate that the state’s current plan elements and strategies are 

sufficient to meet our obligations related to the reasonable progress goals of the Northern Midwest 

Class I areas.

19 Map provided at: http://www.epa.gov/air/particlepollution/actions.html.

22

 
7. 40 CFR 51.308(g)(7): Visibility Monitoring

40 CFR 51.308(g)(7) requires: “A review of the State's visibility monitoring strategy and any 

modifications to the strategy as necessary.”

The DNR currently operates two IMPROVE Protocol sampling sites, one at Viking Lake State Park in 

southwestern Iowa, and the other at the Lake Sugema Wildlife Management Area in southeastern Iowa.

The monitors began operation in June 2002. Additional monitoring equipment located at these two 

locations provides supplemental information on fine particles and their precursors. Data from IMPROVE 

and IMPROVE protocol monitors is analyzed by a national laboratory (funded via an interagency 

agreement between EPA and the National Park Service) and uploaded by the laboratory into two 

publicly available databases at http://vista.cira.colostate.edu/improve and 

http://vista.cira.colostate.edu/views/. The supplemental monitoring data is publicly available at 

http://www.epa.gov/airdata/ad_maps.html and at http://www.epa.gov/ttn/airs/airsaqs. The DNR 

intends to continue to operate the two IMPROVE protocol monitors as long as the interagency 

agreement is in place and funding is available.

23
8. 40 CFR 51.308(h): Determination of Plan Adequacy

40 CFR 51.308(h) requires: “...At the same time the State is required to submit any 5-year progress 

report to EPA in accordance with paragraph (g) of this section, the State must also take one of the 

following actions based upon the information presented in the progress report:

(1) If the State determines that the existing implementation plan requires no further substantive revision 

at this time in order to achieve established goals for visibility improvement and emissions reductions, the 

State must provide to the Administrator a negative declaration that further revision of the existing 

implementation plan is not needed at this time.

(2) If the State determines that the implementation plan is or may be inadequate to ensure reasonable 

progress due to emissions from sources in another State(s) which participated in a regional planning 

process, the State must provide notification to the Administrator and to the other State(s) which 

participated in the regional planning process with the States. The State must also collaborate with the 

other State(s) through the regional planning process for the purpose of developing additional strategies 

to address the plan's deficiencies.

(3) Where the State determines that the implementation plan is or may be inadequate to ensure 

reasonable progress due to emissions from sources in another country, the State shall provide 

notification, along with available information, to the Administrator.

(4) Where the State determines that the implementation plan is or may be inadequate to ensure 

reasonable progress due to emissions from sources within the State, the State shall revise its 

implementation plan to address the plan's deficiencies within one year.”

Based upon the evidence presented in this document and the options above the DNR has determined 

that further revision of the existing implementation plan is not needed at this time. A negative 

declaration to this effect, as required by 40 CFR 51.308(h), is included in the transmittal letter for this SIP

(see Chapter i).

 

24
9. Stakeholder Input

FLM Consultation

The Federal Land Managers (FLMs) were provided a copy of the draft SIP on April 4, 2013. The public 

hearing was held on June 11, 2013, which is in accordance with the FLM coordination requirements of 

51.308)(i)(2). Comments received from the FLMs are summarized and addressed in Appendix D. 

The DNR will continue to coordinate and consult with the FLMs during development of future plan 

provisions and progress reports, as well as during the implementation of programs having the potential 

to contribute to visibility impairment in Class I areas. The DNR will continue to communicate with the 

FLMs individually, through interagency or other coordinated efforts, or both to meet the requirements 

of 51.308(i)(4), which requires procedures for consultation during: 

• Development and review of implementation plan revisions,

• Review of 5-year progress reports,

• Development and implementation of other programs that may contribute to impairment of 

visibility in Class I areas.

To enhance interstate consultation efforts, the states of Minnesota and Michigan were each provided a 

copy of the draft SIP concurrent with the FLM review period. The DNR has and continues to be available 

for consultation concerning the Northern Midwest Class I areas. No requests for continued discussions 

have been received since the DNR submitted its initial regional haze SIP. 

Public Notice

The DNR provided public notice of the opportunity to comment on the SIP revision. Public comments 

received on the draft SIP are summarized and addressed in Appendix D. The DNR has the authority to 

adopt this SIP revision (see Appendix E) and has adopted this revision in accordance with State laws and 

rules.

A copy of this report is available at the Iowa Department of Natural Resources – Air Quality Bureau, 

Records Center, 7900 Hickman Rd, Ste 1, Windsor Heights, IA 50324, and on our website at 

www.iowacleanair.gov.

25
Appendix A. Source Apportionment Review

This appendix provides a brief review of visibility degradation source apportionment results for the 20% 

worst visibility days from the 2002 basecase and 2018 Base-E CAMx particulate matter source 

apportionment (PSAT) modeling conducted for the initial regional haze SIP.

20 The source apportionment 

results provided estimates of the contributions to visibility impairment at Class I areas by source regions

(e.g. states) and source categories. The modeled concentrations from the PSAT results were converted 

to light extinction values (a measure of visibility impairment with units of inverse megameters, Mm-1

)

using the new21 IMPROVE equation. 

The intent of the CENRAP PSAT analysis was to obtain separate contributions due to onroad mobile, 

nonroad mobile, area, natural (biogenic), EGU point, and non-EGU point source categories. However,

separate source apportionment modeling of EGU and non-EGU point sources was not possible for all 

states due to technical considerations. The six source categories that were separately tracked in the 

PSAT modeling were:

• Elevated point sources (i.e. larger industrial sources and power plants),

• Low-level point sources (i.e. point source emissions emitted into layer 1 of the model),

• Onroad Mobile Sources,

• Nonroad Mobile Sources,

• Area Sources, and

• Natural Sources (e.g. biogenic).

According to the PSAT results the combined effect of all Iowa emissions upon the total modeled visibility 

impairment at the four Northern Midwest Class I is approximately 4 – 5 % in both 2002 and 2018. This 

represents a contribution of ~2.0 – 4.5 Mm-1 to the total modeled light extinction at the northern 

Midwest Class I areas. These results are reviewed in Table A-1.

Table A-1. Iowa’s contributions to modeled visibility impairment (using the new IMPROVE equation) 

for the 20% worst days at the Northern Midwest Class I areas.

22

Site

Iowa’s Percentage

Contribution

Iowa’s Total Modeled 

Contribution (Mm-1)

Class I Area Total Modeled 

Impairment (Mm-1)

2002 2018 2002 2018 2002 2018

BOWA 3.7% 3.9% 2.39 2.08 64.87 53.44

VOYA 3.8% 4.0% 2.16 1.97 56.45 48.84

ISLE 4.5% 4.9% 3.23 3.02 71.40 61.26

SENE 4.2 % 4.8 % 4.54 3.95 107.92 82.00

20 The PSAT modeling was funded by CENRAP and conducted by ENVIRON. The PSAT results were consolidated 

within and evaluated using ENVIRON’s PSAT Tool (Microsoft Access based). See Appendix 7.1 of Iowa’s initial 

regional haze SIP for additional information. 21 Note, Appendix 7.1 of the initial regional haze SIP (see page 5-14 of the appendix) states that the original 

IMPROVE equation was used to convert modeled concentrations to light extinction. However, an updated version 

of the PSAT Tool (version 1.2, dated August 27, 2007) was used for both the initial regional haze SIP and this 

progress report. The updated PSAT Tool used the new, and not the original, IMPROVE equation.

22 The data are from Tables 11.1 and 11.2 of the initial regional haze SIP.

26

 
The above results focus solely upon contributions attributable to sources in Iowa. The charts below 

provide a graphical representation comparing how all source regions (e.g. states) contribute to the total 

modeled visibility impairment at the Northern Midwest Class I areas.

23 The results are also apportioned 

by pollutant and source categories. There are four charts per Class I area, two plots each for the 2002

and 2018 results (Figures A-1 through A-16). The first chart provides results for the worst 20% visibility 

days in 2002 for Boundary Waters Canoe Area Wilderness (BOWA) in Minnesota. In this chart the 

visibility impairment is apportioned by state and source category. The same visibility impairment data 

(worst 20% days in 2002 at BOWA) form the basis for the second plot but the results are apportioned by 

pollutant (and state). Source apportionment results for the worst 20% visibility days in 2018 at BOWA 

are similarly plotted in the next two charts. The remaining charts pertain to Voyageurs National Park 

(VOYA) in Minnesota, and Isle Royale National Park (ISLE) and Seney Wilderness Area (SENE) in 

Michigan.

For simplicity only the raw modeled 2002 and 2018 PSAT results are provided.

24 While the total 

modeled visibility degradation is provided in the title of each chart, contributions from initial conditions

(IC), boundary conditions (BC), anthropogenic secondary organic aerosol (SOAA), and biogenic 

secondary organic aerosol (SOAB) are only shown when results are apportioned by pollutant. 

23 The 2018 data plotted below are the same as shown in Figures 11.1 – 11.4 of the initial regional haze SIP. 

Additional charts are included here for an expanded review, to include the 2002 results and PSAT contributions by 

source categories.

24 The PSAT results that were scaled according to observed species ratios (referred to as the “Projected” results 

within the PSAT tool) are not utilized in this review.

27

 
Figure A-1. CENRAP PSAT source region by source category contributions to the average 2002 

extinction (Mm-1

) for the worst 20% visibility days at Boundary Waters (BOWA), Minnesota.

Figure A-2. CENRAP PSAT source region by pollutant contributions to the average 2002 extinction 

(Mm-1

) for the worst 20% visibility days at Boundary Waters (BOWA), Minnesota.

CENRAP PSAT Modeled W20% 2002 BEXT at Site BOWA1 [Total=64.87]

0

1

2

3

4

5

6

7

8

9

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11

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18

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

Source Region

Extinction (1/Mm)

Elevated Point Low-Level Point Natural On-Road Mobile Non-Road Mobile Area

CENRAP PSAT Modeled W20% 2002 BEXT at Site BOWA1 [Total=64.87]

0

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East Texas

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OklahomaArkansas

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Colorado

New Mexico

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Illinois

Indiana

Ohio

Michigan

Kentucky

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Gulf of Mexico

East

West

Canada

Mexico

IC

BC

SOAA

SOAB

Source Region

Extinction (1/Mm)

SO4 NO3 POA EC SOIL CM SOAA SOAB

28
Figure A-3. CENRAP PSAT source region by source category contributions to the average 2018 

extinction (Mm-1

) for the worst 20% visibility days at Boundary Waters (BOWA), Minnesota. 

Figure A-4. CENRAP PSAT source region by pollutant contributions to the average 2018 extinction 

(Mm-1

) for the worst 20% visibility days at Boundary Waters (BOWA), Minnesota.

CENRAP PSAT Modeled W20% 2018 BEXT at Site BOWA1 [Total=53.44]

0

1

2

3

4

5

6

7

8

9

10

11

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13

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East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

Source Region

Extinction (1/Mm)

Elevated Point Low-Level Point Natural On-Road Mobile Non-Road Mobile Area

CENRAP PSAT Modeled W20% 2018 BEXT at Site BOWA1 [Total=53.44]

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

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16

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

IC

BC

SOAA

SOAB

Source Region

Extinction (1/Mm)

SO4 NO3 POA EC SOIL CM SOAA SOAB

29
Figure A-5. CENRAP PSAT source region by source category contributions to the average 2002 

extinction (Mm-1

) for the worst 20% visibility days at Voyageurs (VOYA), Minnesota.

Figure A-6. CENRAP PSAT source region by pollutant contributions to the average 2002 extinction 

(Mm-1

) for the worst 20% visibility days at Voyageurs (VOYA), Minnesota.

CENRAP PSAT Modeled W20% 2002 BEXT at Site VOYA2 [Total=56.45]

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

Source Region

Extinction (1/Mm)

Elevated Point Low-Level Point Natural On-Road Mobile Non-Road Mobile Area

CENRAP PSAT Modeled W20% 2002 BEXT at Site VOYA2 [Total=56.45]

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

IC

BC

SOAA

SOAB

Source Region

Extinction (1/Mm)

SO4 NO3 POA EC SOIL CM SOAA SOAB

30
Figure A-7. CENRAP PSAT source region by source category contributions to the average 2018 

extinction (Mm-1

) for the worst 20% visibility days at Voyageurs (VOYA), Minnesota.

Figure A-8. CENRAP PSAT source region by pollutant contributions to the average 2018 extinction 

(Mm-1

) for the worst 20% visibility days at Voyageurs (VOYA), Minnesota.

CENRAP PSAT Modeled W20% 2018 BEXT at Site VOYA2 [Total=48.84]

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

Source Region

Extinction (1/Mm)

Elevated Point Low-Level Point Natural On-Road Mobile Non-Road Mobile Area

CENRAP PSAT Modeled W20% 2018 BEXT at Site VOYA2 [Total=48.84]

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

IC

BC

SOAA

SOAB

Source Region

Extinction (1/Mm)

SO4 NO3 POA EC SOIL CM SOAA SOAB

31
Figure A-9. CENRAP PSAT source region by source category contributions to the average 2002 

extinction (Mm-1

) for the worst 20% visibility days at Isle Royale (ISLE), Michigan.

Figure A-10. CENRAP PSAT source region by pollutant contributions to the average 2002 extinction 

(Mm-1

) for the worst 20% visibility days at Isle Royale (ISLE), Michigan.

CENRAP PSAT Modeled W20% 2002 BEXT at Site ISLE1 [Total=71.4]

0

1

2

3

4

5

6

7

8

9

10

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

Source Region

Extinction (1/Mm)

Elevated Point Low-Level Point Natural On-Road Mobile Non-Road Mobile Area

CENRAP PSAT Modeled W20% 2002 BEXT at Site ISLE1 [Total=71.4]

0

1

2

3

4

5

6

7

8

9

10

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

IC

BC

SOAA

SOAB

Source Region

Extinction (1/Mm)

SO4 NO3 POA EC SOIL CM SOAA SOAB

32
Figure A-11. CENRAP PSAT source region by source category contributions to the average 2018 

extinction (Mm-1

) for the worst 20% visibility days at Isle Royale (ISLE), Michigan.

Figure A-12. CENRAP PSAT source region by pollutant contributions to the average 2018 extinction 

(Mm-1

) for the worst 20% visibility days at Isle Royale (ISLE), Michigan.

CENRAP PSAT Modeled W20% 2018 BEXT at Site ISLE1 [Total=61.26]

0

1

2

3

4

5

6

7

8

9

10

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

Source Region

Extinction (1/Mm)

Elevated Point Low-Level Point Natural On-Road Mobile Non-Road Mobile Area

CENRAP PSAT Modeled W20% 2018 BEXT at Site ISLE1 [Total=61.26]

0

1

2

3

4

5

6

7

8

9

10

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

IC

BC

SOAA

SOAB

Source Region

Extinction (1/Mm)

SO4 NO3 POA EC SOIL CM SOAA SOAB

33
Figure A-13. CENRAP PSAT source region by source category contributions to the average 2002 

extinction (Mm-1

) for the worst 20% visibility days at Seney (SENE), Michigan.

Figure A-14. CENRAP PSAT source region by pollutant contributions to the average 2002 extinction 

(Mm-1

) for the worst 20% visibility days at Seney (SENE), Michigan. 

CENRAP PSAT Modeled W20% 2002 BEXT at Site SENE1 [Total=107.92]

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

Source Region

Extinction (1/Mm)

Elevated Point Low-Level Point Natural On-Road Mobile Non-Road Mobile Area

CENRAP PSAT Modeled W20% 2002 BEXT at Site SENE1 [Total=107.92]

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

IC

BC

SOAA

SOAB

Source Region

Extinction (1/Mm)

SO4 NO3 POA EC SOIL CM SOAA SOAB

34
Figure A-15. CENRAP PSAT source region by source category contributions to the average 2018 

extinction (Mm-1

) for the worst 20% visibility days at Seney (SENE), Michigan.

Figure A-16. CENRAP PSAT source region by pollutant contributions to the average 2018 extinction 

(Mm-1

) for the worst 20% visibility days at Seney (SENE), Michigan. 

CENRAP PSAT Modeled W20% 2018 BEXT at Site SENE1 [Total=82]

0

1

2

3

4

5

6

7

8

9

10

11

12

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

Source Region

Extinction (1/Mm)

Elevated Point Low-Level Point Natural On-Road Mobile Non-Road Mobile Area

CENRAP PSAT Modeled W20% 2018 BEXT at Site SENE1 [Total=82]

0

1

2

3

4

5

6

7

8

9

10

East Texas

TX Gulf Coast

West Texas

Louisiana

OklahomaArkansas

Missouri

Kansas

Nebraska

Iowa

Minnesota

North Dakota

South Dakota

Wyoming

Colorado

New Mexico

Wisconsin

Illinois

Indiana

Ohio

Michigan

Kentucky

Tennessee

Mississippi

Alabama

Gulf of Mexico

East

West

Canada

Mexico

IC

BC

SOAA

SOAB

Source Region

Extinction (1/Mm)

SO4 NO3 POA EC SOIL CM SOAA SOAB

35
Appendix B. MACT Review

Numerous Maximum Achievable Control Technology (MACT) standards have been promulgated 

pursuant to Section 112 of Title I of the Clean Air Act. MACT standards are designed to reduce emissions 

of air toxics, also known as hazardous air pollutants (HAPs), from stationary sources of air pollution. A 

significant percentage of the MACT standards yield VOC reductions since many HAPs are also VOCs. 

While VOC emissions were not specifically targeted for reduction in the initial regional haze SIP, NOx 

emissions reductions were expected from the 2004 Reciprocating Internal Combustion Engines (RICE) 

standards. PM reductions were also possible from a subset of the applicable standards.

CENRAP estimated emissions reductions from the MACT standards for source categories with a post2002 compliance data. MACT standards not achieving significant VOC emission reductions were 

excluded. A list of the MACT standards considered in development of the 2018 inventory for the initial

regional haze SIP is provided in Table B-1. This table also provides the associated CFR subpart containing 

the regulations, the compliance date for existing sources, and the pollutants reduced in the 2018 

inventory. Not all source categories listed in Table B-1 are found in Iowa, the list is based upon the data 

developed by E.H. Pechan and Associates.25 It is likely that the MACT standards did not significantly 

impact any relationships between emission in Iowa and visibility impairment in a Class I area. Their 

review is provided only as a courtesy and for future reference.

Table B-1. Post-2002 MACT standards considered in the 2018 emissions inventory

MACT Standard - Source 

Category

CFR 

Subpart

Promulgation

(Federal Register)

Compliance Date 

(existing sources)

Pollutants

Affected

Asphalt (Roofing Manufacturing 

& Asphalt Processing) LLLLL 4/29/2003 5/1/2006 VOC

Auto and Light Duty Trucks IIII 4/26/2004 4/26/2007 VOC

Coke Ovens: Pushing, Quenching 

and Battery Stacks CCCCC 4/14/2003 4/14/2006 VOC

Fabric Printing, Coating &Dyeing OOOO 5/29/2003 5/29/2006 VOC

Friction Products Manufacturing QQQQQ 10/18/2002 10/18/2005 VOC

Integrated Iron and Steel FFFFF 5/20/2003 5/20/2006 VOC, PM

Large Appliances NNNN 7/23/2002 7/23/2005 VOC

Leather Finishing Operations TTTT 2/27/2002 2/27/2005 VOC

Lime Manufacturing AAAAA 1/5/2004 1/5/2007 PM

Manufacturing Nutritional Yeast CCCC 5/21/2001 5/21/2004 VOC

Metal Can (Surface Coating) KKKK 11/13/2003 11/13/2006 VOC

Metal Coil (Surface Coating) SSSS 6/10/2002 6/10/2005 VOC

Metal Furniture RRRR 5/23/2003 5/23/2006 VOC

Misc. Coating Manufacturing HHHHH 12/11/2003 12/11/2006 VOC

Misc. Metal Parts and Products

(Surface Coating) MMMM 1/2/2004 1/2/2007 VOC

25 Development of Growth and Control Inputs for CENRAP 2018 Emissions, Draft Technical Support Document.

E.H. Pechan and Associates, Inc. Durham, North Carolina. Carolina Environmental Program, University of North 

Carolina, Chapel, Hill, North Carolina. 2005, May.

36

 
Misc. Organic Chemical 

Production and Processes 

(MON)

FFFF 11/10/2003 11/10/2006 VOC

Paper and Other Web JJJJ 12/4/2002 12/4/2005 VOC

Pesticide Active Ingredient 

Production MMM 6/23/1999 12/23/2003 VOC

Petroleum Refineries UUU 4/11/2002 4/11/2005 VOC

Plastic Parts PPPP 4/19/2004 4/19/2007 VOC

Plywood and Composite Wood 

Products DDDD 7/30/2004 10/1/2007 VOC

Polymers and Resins III OOO 1/20/2000 1/20/2003 VOC

Reciprocating Internal

Combustion Engines (RICE) ZZZZ 6/15/2004 6/15/2007 VOC, NOx

Rubber Tire Manufacturing XXXX 7/9/2002 7/11/2005 VOC

Secondary Aluminum Production RRR 3/23/2000 3/24/2003 PM

Site Remediation GGGGG 10/8/2003 10/8/2006 VOC

Solvent Extraction for Vegetable 

Oil Production GGGG 4/12/2001 4/12/2004 VOC

Stationary Combustion Turbines YYYY 3/5/2004 3/5/2007 VOC

Taconite Iron Ore Processing RRRRR 10/30/2003 10/30/2006 PM

Wet Formed Fiberglass Mat 

Production HHHH 4/11/2002 4/11/2005 VOC

Wood Building Products (Surface 

Coating) QQQQ 5/28/2003 5/28/2006 VOC

2004 Industrial/Commercial/Institutional Boiler NESHAP

The original regional haze SIP indicated that the future year 2018 emissions inventory included 

emissions reductions associated with the industrial, commercial, and institutional (ICI) boiler MACT.

26 

Upon further review it does not appear any such adjustments were actually incorporated. The vacature 

and remand of the ICI boiler MACT issued by the DC Circuit court of Appeals on July 30, 2007, would 

have called into question the accuracy of any previous attempts to quantify the effects of the ICI boiler 

MACT. On January 31, 2013, EPA published the final reconsideration amendments of the ICI boiler 

MACT. The compliance dates for the rule are January 31, 2016, for existing sources and January 31, 

2013, or upon startup, whichever is later, for new sources. Additional review of the potential effects of 

the boiler MACT can better be assessed during the comprehensive regional haze SIP review due July 31, 

2018. 

26 The ICI boiler MACT was published in the Federal Register September 13, 2004, affecting 40 CFR 63 subpart 

DDDDD.

37

 
Appendix C. Emissions Data Compilation

A meaningful comparison of the 2008 NEI version 2 (version dated April 10, 2012)27 emission data with 

the 2002 and 2018 data requires the underlying data be similarly categorized. A review of the source 

categories used in the initial regional haze SIP is provided below. A detailed accounting of how the 2008 

NEIv2 data was processed to ensure emission were consolidated using a classification system highly 

similar to 2002/2018 categories will follow. 

Categories from the Initial Regional Haze SIP

Historically emissions were classified according to five basic source categories: area, offroad, onroad, 

point, and biogenic sources.28 This basic classification scheme was expanded in the 2002 and 2018 

regional haze emissions inventories developed for CENRAP to include specialized source categories for

road dust, fugitive dust, ammonia, three distinct fire categories, and the separation of the point sector 

into emissions from electrical generating units (EGUs) and non-EGUs. For this five-year progress report

the three fire categories used in the 2002/2018 inventories have been summed into a single fires 

category. This results in ten source categories: ammonia, area, fugitive dust, offroad, onroad, point 

EGU, point non-EGU, road dust, fires, and biogenics. A simple summary of these categories and the 

types of sources they included (in the 2002 and 2018 regional haze inventories) is provided in Table C-1.

Table C-1. Identification and description of the source categories used to classify the 2002 and 2018 

emissions in the initial regional haze SIP.

Ammonia

Essentially an area source category that pertained only to NH3 emissions. 

Emissions sources considered included agricultural livestock waste, agricultural 

fertilizer application, landfills, wildlife (deer), domestic pets, and human 

perspiration and respiration. This is not an exhaustive list but includes the most 

significant sources. Agricultural livestock and fertilizer applications accounted for 

over 95% of the 2002 Ammonia category emissions.

Area

Included a wide variety of emissions types and was intended to include all 

emissions not otherwise represented by one of the other nine categories. Common 

examples of area sources include gas stations, solvent utilization, and residential 

wood combustion.

Fugitive Dust

Included only PM10 and PM2.5 fugitive emissions associated with mining, 

construction, crop production, and dust kicked up by hooves at beef feedlots 

(drylots).

Offroad

Generally included all nonroad mobile source activities, such as: airport; marine; 

rail (locomotive); residential (e.g. lawn care); agricultural equipment; construction 

and mining equipment (not associated with fugitive dust); and recreational 

equipment. This is not an exhaustive list.

Onroad Included emissions resulting from rural and urban roadway traffic from cars, trucks, 

buses, motorcycles, etc.

Point EGU Emissions from large facilities producing electricity for sale. For example, this 

category commonly included facilities that have units subject to the Acid Rain 

27 This inventory will be referred to simply as the 2008 NEIv2. It was the most recent comprehensive NEI dataset 

available. All 2008 NEI data used in this document is from this version. 28 The area source category is also referred to as the nonpoint source category and the offroad source category 

referred to as the as nonroad source category. For purposes of this document the respective terms are considered 

to be interchangeable.

38

 
Program or the Clean Air Interstate Rule (CAIR).

Point non-EGU Emissions from large industrial activities not associated with electricity generation.

Road Dust Included only PM10 and PM2.5 emissions from paved and unpaved roads.

Fires

Included emissions from prescribed fires, agricultural field burning, and wildfires. 

(Larger prescribed fires were categorized as ‘Point Fire’ in the 2002/2018

inventories, with the ‘Area Fire’ category consisting of smaller prescribed fires and 

agricultural field burning. Wildfire and agricultural burning are not common in 

Iowa.)

Biogenic Included NOx and VOC emissions produced by the BEIS3 biogenic emissions model.

2008 NEI Data Categories

The classification system used by EPA in the 2008 NEI has changed in some respects compared to the 

allocation methods used in initial regional haze SIP.

29 For example, certain emissions from aircraft, 

locomotives, and commercial marine vessels that were considered offroad emissions in the initial 

regional haze SIP are associated with point sources or nonpoint sources in the 2008 NEI.

30

To help ensure the 2008 NEIv2 data were consolidated into categories comparable to the 2002 

inventory, the 2008 NEIv2 data were processed using the full detail SCC (source classification code) Data 

Files provided by EPA for the Point, OnRoad, NonRoad (offroad), and NonPoint (area) data categories. 

The Iowa specific 2008 emissions were first extracted from the SCC Data Files and the resultant data 

reclassified where necessary to align the 2002/2018 and 2008 source categories as closely as possible. 

For example, aircraft and rail emissions were extracted from the Point SCC Data File and reclassified as 

offroad sources. Commercial marine emissions in the 2008 NonPoint SCC Data File were extracted and

reclassified as offroad sources. The fugitive dust category was defined by including emissions from 

agricultural activities, construction dust, and mining emissions from the NonPoint SCC Data File. A 

lookup table is provided below which provides additional detail regarding how the 2008 NEIv2 data 

were cataloged for comparison to the ten source categories utilized in the initial regional haze SIP. 

A minor complicating factor arises between the comparison of the 2002/2018 and 2008 ammonia 

category data. The 2002/2018 and 2008 inventories both include emissions from livestock waste and 

fertilizer applications, but only the 2002/2018 inventories include other source types such as waste 

disposal, miscellaneous, and biogenics. However, these exclusions are not expected to significantly 

compromise the legitimacy of the comparison as livestock waste and fertilizer application sources 

accounted for over 95% of the total emissions in the 2002 ammonia category and similar conditions 

would be expected of 2008.

Changes and transitions in the methods, datasets, and models used to estimate emissions are expected 

to create additional, but unavoidable, discontinuities between the 2002/2018 and 2008 NEI data. For 

example, Chapter 4 and Chapter 5 discuss updates in the onroad and NH3 emissions methodologies, 

respectively. Such differences may moderate the comparability of some source categories but are not 

known to affect any substantive conclusions in this document. Significant inter-annual discrepancies in 

the point source categories, which are important components of this five year review, are not expected. 

29 EPA’s descriptions of the 2008 NEI source categories are included at the end of this appendix. 30 Aircraft engine emissions occurring during landing and takeoff operations and the ground support equipment 

and auxiliary power units associated with the aircraft are considered point sources associated with individual 

airports in the 2008 NEI. Emissions from locomotives that occur at rail yards are also included as point sources. 

Commercial marine vessel emissions are considered nonpoint sources.

39

 
2008 Emissions Classifications Lookup Table

The first column in Table C-2 identifies the 2008 NIEv2 SCC Data File (Point, NonPoint, OnRoad, or Nonroad)

31 from which the Iowa data were

extracted, with the following caveats: 

• An ‘AirRail’ identifier was created to denote aircraft and locomotive emissions extracted from the Point SCC Data File.

• The ‘Biogenics’ identifier reflects emissions data obtained from the “Biogenics - Vegetation and Soils” Emissions Inventory System (EIS)

Sector summary file. (Biogenic emissions were not included in any SCC Data File.)

• The ‘Fire’ identifier represents prescribed fire emissions from the “Fires - Prescribed Fires” EIS Sector summary file in addition to 

agricultural burning emissions contained in the NonPoint SCC Data File. 

The second column in Table C-2 groups emissions from the SCC Data Files by EPA’s EIS Sectors.

32 

The 2008 NEIv2 emissions estimates are reported in columns 3 through 8 of Table C-2, in tons per year. The PM25-PRI and PM10-PRI data 

represent the sum of filterable and condensable (if any) emission. 

The last column in Table C-2 identifies which category (of the ten source categories used in the initial regional haze SIP) was selected to classify 

those 2008 emissions. Note, the classification system used to process the 2008 NEIv2 data could not recreate the categories used in the initial 

regional haze SIP perfectly (most notable for the Ammonia category) but other classification discrepancies are not known to be significant. 

Additional information about the ten categories as they pertain to the 2008 NEIv2 data follows:

31 The four SCC Data Files were large (potentially many hundreds of megabytes) national scale datasets, obtained from EPA’s website: 

http://www.epa.gov/ttnchie1/net/2008inventory.html. 

32 For the 2008 NEIv2 EPA developed convenient summaries (e.g. pollutant emissions summed by state) using 60 different EIS Sector Summary files. 

Unfortunately, the EIS Sector summaries could not be distributed in a manner which would cleanly recreate the ten categories used in the initial regional haze 

SIP. For example, EPA’s “Industrial Processes - Mining” EIS Sector summary consolidated emissions that under the 2002/2018 classifications would consist of 

both fugitive dust and point source (non-EGU) emissions. While such discrepancies may not always be significant, such errors were avoided by instead 

processing the emissions data from the four SCC Data Files. Additional information regarding the data and processing steps follows.

Every emissions record in each of the four SCC Data Files contains a source classification code. For the 2008 NEIv2 EPA developed a crosswalk file 

(ftp://ftp.epa.gov/EmisInventory/2008v2/doc/scc_eissector_xwalk_2008neiv2.xlsx) that maps every source classification code to one of 60 EIS sectors. By first 

processing the SCC Data Files separately (and then reviewing the descriptions associated with source classification codes where uncertainty remained 

regarding the appropriate classification) it was possible to utilize the EIS Sectors classifications while still ensuring emissions could be appropriately assigned

into one of the ten categories used in the initial regional haze SIP. For example, this process helped to ensure mining related emissions from the NonPoint SCC 

Data File could be appropriately identified as “Fugitive Dust” emissions and kept separate from mining emissions from the Point SCC Data File which needed to 

be categorized as “Point non-EGU” emissions. This explains why an EIS Sector, e.g. “Industrial Processes-Mining,” may be listed more than once in Table C-2.

40

 
• The Ammonia category includes only NH3 emissions from agricultural livestock waste and agricultural fertilizer applications (nonpoint

emissions). The 2002/2018 inventories included additional sectors (examples provided in Table C-1) but these additional sources either 

could not be segregated from the 2008 SCC Data Files in an efficient manner or were not present (such as emissions associated with 

human respiration and perspiration) in the 2008 NEIv2 data. These exclusions do not compromise the comparison as they are expected 

to contribute only a small percentage (approximately 5% or less) of the total ammonia emissions in this category.

• The Area category includes all other emissions from the NonPoint SCC Data File not otherwise classified.

• The Fugitive Dust category includes agricultural crop and livestock dust, construction dust, and nonpoint mining dust. Transport factors 

have not been applied to these emissions.

• The Offroad category includes aircraft and locomotive emissions from the Point SCC Data File, commercial marine and locomotive 

emissions from the NonPoint SCC Data File, and all emissions in the NonRoad SCC Data File.

• The Onroad category includes all emissions from the OnRoad SCC Data File.

• The Point-EGU category includes all emissions from the Point SCC Data File that are categorized with one of the following EIS Sectors: 

Fuel Comb - Electric Generation - Biomass, Fuel Comb - Electric Generation - Coal, Fuel Comb - Electric Generation - Natural Gas, Fuel 

Comb - Electric Generation - Oil, Fuel Comb - Electric Generation - Other.

• The Point non-EGU category includes all other industrial point source emissions.

• The Road Dust category includes paved and unpaved road dust from the NonPoint SCC Data File.

• The Fires category includes agricultural field burning from the NonPoint SCC Data File, and prescribed fire from the EIS Sector file: “FiresPrescribed fires” (classified as an Event category under the 2008 nomenclature). As a reasonable assumption, no wildfire emissions 

were estimated in Iowa.

• The Biogenics category includes emissions obtained from the EIS-Sector File: “Biogenics - Vegetation and soil”

Table C-2. Lookup table defining how emissions from the 2008 NEIv2 SCC Data Files were categorized for comparison with the 2002/2018 

emissions data from the initial regional haze SIP. Emissions data also provided (tons).

2008 NEIv2

SCC Data

File

2008 NEIv2 EIS Sector VOC NOX PM25-

PRI

PM10-

PRI NH3 SO2 Categorization

NonPoint Agriculture - Crops & Livestock Dust 66,996 334,982 Fugitive Dust

NonPoint Agriculture - Fertilizer Application 89,461 Ammonia

NonPoint Agriculture - Livestock Waste 206,087 Ammonia

Biogenics Biogenics - Vegetation and soil 289,743 35,620 Biogenic

Point Bulk Gasoline Terminals 631 5 0 0 - - Point Non-EGU

NonPoint Commercial Cooking 109 - 769 770 - Area

41
2008 NEIv2

SCC Data

File

2008 NEIv2 EIS Sector VOC NOX PM25-

PRI

PM10-

PRI NH3 SO2 Categorization

NonPoint Dust - Construction Dust 2,523 25,230 Fugitive Dust

NonPoint Dust - Paved Road Dust 4,507 18,027 Road Dust

NonPoint Dust - Unpaved Road Dust 12,847 129,564 Road Dust

NonPoint Fires - Agricultural Field Burning 951 475 1,562 1,562 54 Fires

Fire Fires - Prescribed Fires 3,410 283 1,303 1,538 237 134 Fires

Point Fuel Comb - Comm/Institutional - Biomass - - - - - Point Non-EGU

Point Fuel Comb - Comm/Institutional - Coal 27 817 56 85 30 4,126 Point Non-EGU

Point Fuel Comb - Comm/Institutional - Natural Gas 24 200 19 21 6 2 Point Non-EGU

Point Fuel Comb - Comm/Institutional - Oil 3 46 5 5 0 99 Point Non-EGU

Point Fuel Comb - Comm/Institutional - Other 0 5 1 2 0 6 Point Non-EGU

Point Fuel Comb - Electric Generation - Biomass - - 1 1 - - Point EGU

Point Fuel Comb - Electric Generation - Coal 659 50,795 5,913 8,459 7 117,622 Point EGU

Point Fuel Comb - Electric Generation - Natural Gas 17 328 67 77 19 13 Point EGU

Point Fuel Comb - Electric Generation - Oil 8 205 12 18 5 15 Point EGU

Point Fuel Comb - Electric Generation - Other 2 20 14 31 0 41 Point EGU

Point Fuel Comb - Industrial Boilers, ICEs - Biomass 6 134 31 64 - 11 Point Non-EGU

Point Fuel Comb - Industrial Boilers, ICEs - Coal 63 7,891 540 1,216 130 30,805 Point Non-EGU

Point Fuel Comb - Industrial Boilers, ICEs - Natural Gas 622 15,984 319 323 52 19 Point Non-EGU

Point Fuel Comb - Industrial Boilers, ICEs - Oil 26 509 19 21 4 121 Point Non-EGU

Point Fuel Comb - Industrial Boilers, ICEs - Other 27 301 20 24 3 72 Point Non-EGU

NonPoint Fuel Comb - Residential - Natural Gas 170 2,907 13 16 618 19 Area

NonPoint Fuel Comb - Residential - Oil 4 97 11 13 5 229 Area

NonPoint Fuel Comb - Residential - Other 167 1,273 50 80 28 1,750 Area

NonPoint Fuel Comb - Residential - Wood 4,643 416 3,933 3,936 229 102 Area

NonPoint Gas Stations 13,952 Area

42
2008 NEIv2

SCC Data

File

2008 NEIv2 EIS Sector VOC NOX PM25-

PRI

PM10-

PRI NH3 SO2 Categorization

Point Gas Stations33 4 - - - - - Point Non-EGU

Point Industrial Processes - Cement Manuf 250 5,293 399 633 37 5,156 Point Non-EGU

Point Industrial Processes - Chemical Manuf 2,117 1,370 190 213 1,129 483 Point Non-EGU

Point Industrial Processes - Ferrous Metals 535 695 509 654 8 490 Point Non-EGU

NonPoint Industrial Processes - Mining 718 5,748 Fugitive Dust

Point Industrial Processes - Mining - - 816 1,243 - - Point Non-EGU

Point Industrial Processes - NEC 10,208 2,264 1,567 2,623 613 1,754 Point Non-EGU

Point Industrial Processes - Non-ferrous Metals 318 49 232 239 3 1 Point Non-EGU

Point Industrial Processes - Oil & Gas Production 62 0 0 0 - - Point Non-EGU

Point Industrial Processes - Petroleum Refineries 1 1 21 21 - - Point Non-EGU

Point Industrial Processes - Pulp & Paper 151 3 100 110 25 - Point Non-EGU

NonPoint Industrial Processes - Storage and Transfer 800 Area

Point Industrial Processes - Storage and Transfer 1,500 26 330 559 1,311 5 Point Non-EGU

NonPoint Miscellaneous Non-Industrial NEC 2,597 10 1 1 2 Area

Point Miscellaneous Non-Industrial NEC - - 0 0 - - Point Non-EGU

AirRail Mobile - Aircraft 120 272 13 59 37 Offroad

NonPoint Mobile - Commercial Marine Vessels 46 2,111 73 75 2 125 Offroad

AirRail Mobile - Locomotives 138 2,140 58 60 1 18 Offroad

NonPoint Mobile - Locomotives 1,211 24,167 748 814 11 248 Offroad

AirRail Mobile - Non-Road Equipment - Diesel34 10 28 1 1 1 Offroad

NonRoad Mobile - Non-Road Equipment - Diesel 4,850 48,455 4,294 4,427 38 1,016 Offroad

AirRail Mobile - Non-Road Equipment - Gasoline34 2 6 0 0 0 Offroad

NonRoad Mobile - Non-Road Equipment - Gasoline 31,753 5,904 705 767 14 29 Offroad

AirRail Mobile - Non-Road Equipment - Other35 2 9 2 2 2 Offroad

33 These emissions are associated with three Magellan Pipeline Co, LLC facilities (located in Des Moines, Sioux City, and Iowa City), not consumer gas stations. 34 Airport/Aircraft ground support activities, extracted from the Point SCC Data File. 35 Aircraft auxiliary power units, extracted from the Point SCC Data File.

43

 
2008 NEIv2

SCC Data

File

2008 NEIv2 EIS Sector VOC NOX PM25-

PRI

PM10-

PRI NH3 SO2 Categorization

NonRoad Mobile - Non-Road Equipment - Other 706 2,738 24 24 5 Offroad

OnRoad Mobile - On-Road Diesel Heavy Duty Vehicles 2,822 41,364 2,216 2,382 87 962 Onroad

OnRoad Mobile - On-Road Diesel Light Duty Vehicles 116 661 57 61 4 23 Onroad

OnRoad Mobile - On-Road Gasoline Heavy Duty Vehicles 1,822 2,821 66 85 47 12 Onroad

OnRoad Mobile - On-Road Gasoline Light Duty Vehicles 36,533 45,784 1,327 1,706 1,377 233 Onroad

NonPoint Solvent - Consumer & Commercial Solvent Use 39,286 Area

Point Solvent - Degreasing 55 - 1 1 - - Point Non-EGU

Point Solvent - Dry Cleaning36 82 - 15 15 - - Point Non-EGU

Point Solvent - Graphic Arts 154 2 0 0 0 0 Point Non-EGU

NonPoint Solvent - Industrial Surface Coating & Solvent Use 1,262 Area

Point Solvent - Industrial Surface Coating & Solvent Use 4,539 50 108 130 1 1 Point Non-EGU

NonPoint Solvent - Non-Industrial Surface Coating 4,534 Area

NonPoint Waste Disposal 875 460 2,189 2,473 11 54 Area

Point Waste Disposal 76 288 62 171 35 17 Point Non-EGU

TOTAL37 464,798 305,282 118,371 551,358 301,676 165,913

36 These point source emissions are associated with the facility “Industrial Laminates/Norplex, Inc.,” which is not a consumer dry cleaner. 37 Note, due to rounding the sum of the numbers in this table may not equal the totals shown.

44

 
Consolidation of the 2002, 2008, and 2018 emissions data

Table C-3 provides a consolidated view of the 2002 base year, 2008 NEIv2 and projected 2018 emissions data. Note, the 2018 SO2 Point EGU emissions reflect the ‘Modified’ value listed in 

Table 7.2 in the initial regional haze SIP. The ‘subtotal’ category represents the sum of all source categories except the biogenic (vegetation and soil emissions) source category. 

Table C-3. Consolidation of the 2002 base year inventory and the 2018 projected inventory from the initial regional haze SIP, and the 2008 NEIv2 emissions data. 

Category VOC NOx PM2.5 PM10 NH3 SO2

2002 2008 2018 2002 2008 2018 2002 2008 2018 2002 2008 2018 2002 2008 2018 2002 2008 2018

Ammonia 0 0 0 0 0 0 0 0 0 0 0 0 258,915 295,549 302,012 0 0 0

Area 106,712 68,399 127,849 6,782 5,163 7,476 11,540 6,967 10,677 12,182 7,288 11,510 6,560 892 13,304 3,184 2,155 3,224

Fugitive Dust 0 0 0 0 0 0 38,666 70,238 40,608 193,331 365,960 203,044 0 0 0 0 0 0

Offroad 63,694 38,837 37,143 92,595 85,831 60,210 8,904 5,918 5,582 9,707 6,228 6,088 79 65 101 9,037 1,481 220

Onroad 87,392 41,293 36,404 120,621 90,630 33,975 1,747 3,666 708 2,373 4,234 708 3,064 1,515 4,225 3,200 1,229 400

Point EGU 1,075 686 1,802 81,761 51,347 65,629 4,527 6,007 9,578 9,424 8,586 11,232 0 31 713 135,833 117,692 151,354

Point Non-EGU 41,184 21,480 56,714 35,812 35,933 40,964 7,651 5,357 10,151 17,495 8,372 21,737 3,317 3,387 5,763 51,836 43,166 42,862

Road Dust 0 0 0 0 0 0 19,525 17,354 17,712 127,882 147,591 114,889 0 0 0 0 0 0

Fires 1,670 4,361 1,672 200 758 200 5,493 2,865 5,495 5,817 3,099 5,819 48 237 49 203 189 204

Subtotal 301,727 175,055 261,584 337,771 269,662 208,454 98,053 118,371 100,511 378,211 551,358 375,027 271,983 301,676 326,167 203,293 165,913 198,264

Biogenic 408,291 289,743 408,291 25,732 35,620 25,732

45
EPA’s Descriptions of the 2008 NEI Source Categories

EPA’s descriptions of the Point, NonPoint, OnRoad, and NonRoad source categories used in the 2008 NEI

are provided below (from http://www.epa.gov/ttnchie1/net/2008inventory.html). As discussed above, 

where EPA’s 2008 NEI source category assignments differ from those used for the 2002/2018 

inventories in the initial regional haze SIP, the 2008 NEI data were re-classified to maximize consistency. 

“The NEI Point data category contains emissions estimates for sources that are individually 

inventoried and usually located at a fixed, stationary location, although portable sources such as 

some asphalt or rock crushing operations are also included. Point sources include large 

industrial facilities and electric power plants, but also increasingly include many smaller 

industrial and commercial facilities, such as dry cleaners and gas stations, which had 

traditionally been included in nonpoint sources. The choice of whether these smaller sources 

are estimated individually and included as point sources or inventoried as a nonpoint source 

County or Tribal area aggregate is determined by the separate State, Local, or Tribal air agency.” 

(Note, smaller source emissions are inventoried in the nonpoint source category in Iowa.)

“The NEI NonPoint data category contains emissions estimates for sources which individually 

are too small in magnitude or too numerous to inventory as individual point sources, and which 

can often be estimated more accurately as a single aggregate source for a County or Tribal area. 

Examples are residential heating and consumer solvent use.

The NEI OnRoad and NonRoad data categories contain mobile sources which are estimated for 

the 2008 NEI v2 via the MOVES and NONROAD models, respectively. NONROAD was run within 

the National Mobile Inventory Model (NMIM). Note that emissions data for aircraft, 

locomotives, and commercial marine vessels are NOT included in the NonRoad data category 

starting with the 2008 NEI. Aircraft engine emissions occurring during Landing and Takeoff 

operations and the Ground Support Equipment and Auxiliary Power Units associated with the 

aircraft are now included in the point data category at individual airports in the 2008 NEI. 

Emissions from locomotives that occur at rail yards are also included in the point data category. 

In-flight aircraft emissions, locomotive emissions outside of the rail yards, and commercial 

marine vessel emissions (both underway and port emissions) are included in the nonpoint data 

category.

The Events data category includes wildfires, wild land fire use and prescribed burns. Wild land 

fire use has been included in the "Fires - Wildfires" sector. Emissions for these are presented as 

county totals on this website.”

46
Appendix D. FLM and Public Comments

The Federal Land Managers (FLMs) were provided a copy of the draft SIP on April 4, 2013, 69 days 

before the public hearing. Notices of the public comment period and public hearing were published in 

the Des Moines Register and posted on the State of Iowa’s Public Meeting Calendar on May 9, 2013. A 

copy of the printed public notice is provided at the end of this appendix. The public hearing was held 

June 11, 2013. Comments received from the FLMs were available during the public hearing. No 

comments were received at the public hearing. Federal Land Manager comments were received from 

the USDA Forest service, and jointly from the National Park Service and U.S. Fish and Wildlife Service. 

Two additional comment letters were received before the public comment period closed on June 12, 

2013. A summary of the comments and the Department’s responses is provided below.

Comments from the USDA Forest Service

FS-1) Comment: Iowa did not incorporate the vast majority of the Forest Service comments when the 

initial Iowa regional haze SIP was finalized, and that many of their concerns were echoed by the National 

Park Service and Environmental Protection Agency. In the technical support documents, the Forest 

Service pointed out that emission controls were shown to be effective on a cost per ton basis, but these 

comments were not incorporated as Iowa determined there would be minimal visibility impact.

If Iowa, as the third largest contributor state, does not require controls because of minimal visibility 

impact, the burden of all the emission reductions to achieve the national visibility goal will fall primarily 

to the states containing Class I areas. The Forest Service encouraged the state to revisit their comments 

on Iowa’s initial regional haze SIP Iowa SIP because they are as applicable today as they were in 2007 

DNR Response: In the initial regional haze SIP submittal the Department appropriately responded to all 

comments provided by the Forest Service and all other public and FLM comments. As was discussed in 

the initial haze SIP, considering costs only on a per ton basis ignores the visibility impairment

component. To achieve the same level of visibility improvement, sources farther from a class I area 

would generally require more reductions than nearby sources. This can significantly elevate the costs of 

visibility improvement to remote sources, especially if their contributions are low. The initial regional 

haze SIP established Iowa’s contribution to the northern class I areas as only 4-5% of the total modeled 

visibility impairment, a small percentage compared to the contributions from Minnesota. Significant 

shifts in the relative state-to-state contributions to visibility impairment have not been identified.

Changes in the relative state-to-state contributions to visibility impairment are expected to be evaluated 

in the next comprehensive SIP review due July 31, 2018. No new information is provided which 

demonstrates controls are available for sources in Iowa which would be cost effective in terms of 

visibility improvement. The Department believes the original response to comments and the existing 

emissions reductions that have occurred since 2002 are sufficient to support existing conclusions and to 

meet the applicable obligations of the five year report. 

FS-2) Comment: The Forest Service acknowledges that the 5-year report shows total emissions of NOx 

and SO2 from all Iowa sources in 2008 declined from the base year (2002). They also note non-EGU NOx 

47
point source emissions increased over the same period. In comparison to 2018 projections, the 2008 

state emissions are lower for SO2 but over 60,000 tons higher for NOx. 

The Forest Service believes more emission reductions in Iowa are appropriate and feasible, and that 

multiple commenters noted the technical information available in 2007 showed that further emission 

reductions in NOx and SO2 were cost effective for both EGUs and non-EGUs. The Forest Service 

provided the following related questions and examples: 

• The Forest Service would like to know the current level of emission controls in place at the 

Holcim facility. The Forest Service believes Holcim should have been subject to a best available 

retrofit technology (BART) determination. 

• The Forest Service notes industrial boilers were identified by the Northern Class I Area 

Workgroup as a class of sources with potential for cost effective controls. These sources are 

included in the point, non-EGU category where NOx emissions increased in Iowa. 

• For EGUs, Minnesota asked Iowa to achieve an SO2 emission rate comparable to Minnesota’s of 

0.25 pounds per million BTU. Based on Figure 2-1, 2011 SO2 emission rates in Iowa are 0.47 

pounds per million BTU. 

DNR Response: The Department does not agree that more emissions reductions in Iowa are 

appropriate at this time or that cost effectiveness should be assessed only in terms of dollars per tons in 

the context of the Regional Haze Rule. The Forest Service does not identify specific controls or specific 

sources where emissions reductions would be feasible, nor are any potential visibility improvements 

provided.

• With respect to concerns over the Holcim Facility, a Portland cement manufacturing facility in 

Mason City, Iowa, manufacturing operations ceased at Holcim in 2009 and the plant has not 

operated since.

• The increase in non-EGU NOx emissions between 2002 and 2008 was 121 tons per year. The 

DNR does not consider this value significant in the context of regional haze. It is also unrealistic

to expect that all NOx emissions reductions projected between 2002 and 2018 in the initial 

regional haze SIP would be achieved by 2008. However, the 2008 non-EGU NOx emissions were 

5,031 tons below 2018 projections, and as of 2008 more than half of the projected 2002 to 2018 

total NOx emissions reductions had been attained. Further emissions reductions from this 

sector are anticipated with the implementation of the Industrial, Commercial, Institutional (ICI)

boiler MACT. Additional review of the potential effects of the ICI boiler MACT can be assessed 

during the comprehensive regional haze SIP review due July 31, 2018. 

The Department concluded in the original regional haze SIP that additional review of the ICI 

boiler emissions was not warranted. This finding continues to be applicable, as does the original

response (reproduced for convenience here):

“Commensurate with the regional haze rule requirements for establishing reasonable 

progress goals, the Department considered the costs of controls in tandem with their 

potential for visibility improvement. Evaluating controls on a dollar per ton basis alone 

does not sufficiently justify their installation. Examining the Four Factor analysis report, 

the EGU cost effectiveness, in terms of dollars per deciview, across the nine-state region 

48
reached $2,994,000,000. This is 83% of the total estimated costs of $3,600,000,000 for 

CAIR. Coupling these values with both the latest MRPO and CENRAP contribution 

analyses that link all Iowa point sources to approximately a 1 - 2 Mm-1 contribution in 

2018, the statements are justified.”

• The state’s overall 2011 EGU SO2 lbs/MMBtu emission rate does not inform or quantify visibility 

impacts. No information was provided which demonstrates Iowa’s overall EGU SO2 emission 

rate is significant in terms of visibility impairment. The lbs/MMBtu emission rate does not 

automatically correlate to visibility impairment, as there is no consideration of distance, 

transport, chemistry, or any other relevant atmospheric factors.

The Department concludes the significant decreases in statewide total SO2 and NOx emissions are 

sufficient to meet the relevant obligations of the five-year regional haze review. 

FS-3) Comment: Decreases in emission rates from the 2002 baseline by themselves are not sufficient to 

determine if a state plan is adequate. The level of decrease must be enough to meet Reasonable 

Progress Goals (RPGs). The RPGs set by Minnesota for the BWCAW were above the uniform rate of 

progress line indicating the pace of emission reductions must increase in the future to achieve the 

national visibility goal. 

Department Response: The Department’s conclusions that the significant and unanticipated decreases 

in Iowa’s emissions are sufficient to determine adequacy of a state plan are consistent with EPA’s April 

12, 2013, guidance memo for the five year reviews (General Principles for the 5-Year Regional Haze 

Progress Reports for the Initial Regional Haze State Implementation Plans). As a small contributor to 

visibility impairment in the Northern Class I areas, Iowa’s ability to effect significant improvements are 

limited, and additional changes to Iowa’s implementation of regional haze requirements are not needed 

at this time. The Regional Haze Rule incorporates an extensive timeframe (to at least 2064) and Iowa 

intends to comply with those timeframes for comprehensive review of the regional haze state 

implementation plan.

Comments from the National Park Service

These comments were provided by the National Park Service (NPS) in consultation with the U.S. Fish & 

Wildlife Service (USFWS). The NPS/USFWS stated that overall Iowa has met the minimum requirements 

for the periodic progress report and concurred that Iowa is not required to discuss monitoring trends in 

the five year review because there are no Class I areas in Iowa. The two NPS/USFWS comments that 

require responses are addressed below.

NPS/USFWS-1) Comment: The NPS/USFWS believe it would be helpful to provide a table of specific 

EGUs in the state that shows what controls were added under CAIR.

DNR Response: For the five-year review the Department believes it is appropriate to evaluate EGU 

emissions comprehensively rather than adding facility-specific components. The addition of controls is 

not necessarily the best indicator of emissions reductions as it does not consider other factors such as 

facility curtailment, fuel-switching, or the degree of control technology utilization.

49
NPS/USFWS-2) Comment: The NPS/USFWS note that it may be appropriate to mention that the 

CENRAP 2002/2018 and the 2008 NEI mobile source inventory data are not directly comparable because 

the methodologies used to calculate the onroad emissions have changed. 

DNR Response: The Department agrees that the use of MOBILE6 in development of the CENRAP 

inventory and the use of the Motor Vehicle Emissions Simulator (MOVES) model by EPA in developing 

the 2008 NEI are significantly different. Chapter 5 of the report has been modified to note the 

discrepancies and discuss potential implications. Appendix C has also been modified to include 

additional discussion regarding changes in emissions methodologies.

Comments from EPA Region 7

EPA-1) Comment: The increase in ammonia emissions (NH3) shown in section 4 of the report is not 

addressed in the narrative. EPA suggests it may be useful to include a brief narrative on the increase in 

ammonia emissions that occurred between 2002 and 2008, as the reason for the increase is not 

apparent to the reader. EPA also notes the 2008 NH3 emissions estimates did not exceed the 2018 

projection.

DNR response: Modifications in the methods used to estimate NH3 emissions likely contribute to the 

differences between the 2002/2018 and 2008 estimates. Chapter 5 has been updated to include a brief 

discussion regarding these changes. Appendix C has also been modified to include additional discussion 

regarding changes in emissions methodologies.

EPA-2) Comment: The opening sentence of the conclusions section in Chapter 6 appears contradictory 

to the rest of the section and the rest of the conclusions.

DNR Response: The word “reductions” was inadvertently omitted from this sentence. The sentence 

has been corrected and is now consistent with the existing conclusions.

EPA-3) Comment: EPA suggests, but does not require, adding trend lines for each emissions category in 

Figure 5-1.

DNR Response: Figure 5-1 provides a comparison of Iowa’s actual emissions for 2002 and 2008, and the 

2018 projections. The scale for the emissions data used in the figure is adequate for readers to discern 

the pollutant trends for each source category. The Department does not believe adding trendlines is 

necessary for communication of the meaning of the data.

Comments from the Minnesota Pollution Control Agency (MPCA)

MPCA Comment: The Minnesota Pollution Control Agency (MPCA) continues to be interested in the 

progress made by sources in Iowa to reduce emissions that contribute to regional haze. The MPCA is 

pleased to note that SO2 and NOx emissions from EGUs in 2011 had decreased from 2008. MPCA also 

50
notes that 2011 levels are well below the projections for 2018. They also note that further reductions of 

SO2 will occur at EGUs that are either subject to a consent decree or will be retired. 

Minnesota also noted that in a letter dated September 19, 2007, they identified a target of reducing SO2 

emissions from EGUs in contributing states to 0.25 lbs/MMBtu to address the improvement goal for the 

20% worst visibility days. Minnesota encourages the state to continue to work towards meeting this 

target. Minnesota also notes their EGU’s have achieved a rate of approximately 0.17 lbs/MMBtu in 

2012, and that they are now more concerned about the relative contribution from EGUs in other states.

DNR Response: The original regional haze modeling conducted by CENRAP indicated Minnesota’s 

contributions to their class I area’s 20% worst impaired visibility days ranged from 26-30%, while Iowa’s 

contributions were five to six times lower (4-5%, see Table 11.1 of Iowa’s initial regional haze SIP). The 

Department did not see a compelling argument from Minnesota that demonstrated how Iowa’s 

adoption of the 0.25 lbs/MMBtu request would benefit Minnesota’s Class I areas. Minnesota provides 

no causal linkage between visibility impairment and a statewide lb/MMBtu EGU emission rate, and 

provides no demonstration that SO2 lb/MMBtu emission rate reductions in Iowa will improve visibility in 

the Minnesota Class I areas. It is appropriate for Minnesota to seek and achieve greater in-state 

reductions as their contributions and source proximities to Class I areas greatly exceed those of Iowa. 

The significant SO2 and NOx emission reductions (tons per year) that have occurred in Iowa since 2002 

are sufficient for Iowa to meet the applicable regional haze obligations. 

51
Public Notice Documents

The following public notice was published in the May 9, 2013, edition of the Des Moines Register. Proof

of publication date can be found in the next page (“0509” in the DATE column).

52
53
The following information was posted to the State of Iowa’s Public Meeting Calendar.

54
Appendix E. Legal Authority

The DNR is the primary state agency responsible for protecting the environment, as indicated in the 

Iowa Code § 455A. The Environmental Protection Commission, established in the Iowa Code § 455A.6, is 

the governing commission for the environmental protection portion of the DNR. The DNR’s authority is 

provided under Iowa Code § 455B.133 and 455B.134 which are listed below. Additional information on 

the Iowa Code is at http://www.legis.iowa.gov/IowaLaw/statutoryLaw.aspx.

455B.133 Duties.

The commission shall:

1. Develop comprehensive plans and programs for the abatement, control, and prevention of air 

pollution in this state, recognizing varying requirements for different areas in the state. The plans may 

include emission limitations, schedules and timetables for compliance with the limitations, measures to 

prevent the significant deterioration of air quality and other measures as necessary to assure attainment 

and maintenance of ambient air quality standards.

2. Adopt, amend, or repeal rules pertaining to the evaluation, abatement, control, and prevention of air 

pollution. The rules may include those that are necessary to obtain approval of the state 

implementation plan under section 110 of the federal Clean Air Act as amended through January 1, 

1991.

3. Adopt, amend, or repeal ambient air quality standards for the atmosphere of this state on the basis of 

providing air quality necessary to protect the public health and welfare and to reduce emissions 

contributing to acid rain pursuant to Tit. IV of the federal Clean Air Act Amendments of 1990.

4. Adopt, amend, or repeal emission limitations or standards relating to the maximum quantities of air 

contaminants that may be emitted from any air contaminant source. The standards or limitations 

adopted under this section shall not exceed the standards or limitations promulgated by the 

administrator of the United States environmental protection agency or the requirements of the federal

Clean Air Act as amended through January 1, 1991. This does not prohibit the commission from adopting 

a standard for a source or class of sources for which the United States environmental protection agency 

has not promulgated a standard. This also does not prohibit the commission from adopting an emission 

standard or limitation for infectious medical waste treatment or disposal facilities which exceeds the 

standards or limitations promulgated by the administrator of the United States environmental 

protection agency or the requirements of the federal Clean Air Act as amended through January 1, 1991. 

The commission shall not adopt an emission standard or limitation for infectious medical waste 

treatment or disposal facilities prior to January 1, 1995, which exceeds the standards or limitations 

promulgated by the administrator of the United States environmental protection agency or the 

requirements of the federal Clean Air Act, as amended through January 1, 1991, for a hospital, or a 

group of hospitals, licensed under chapter 135B which has been operating an infectious medical waste 

treatment or disposal facility prior to January 1, 1991.

a. (1) The commission shall establish standards of performance unless in the judgment of the 

commission it is not feasible to adopt or enforce a standard of performance. If it is not feasible 

to adopt or enforce a standard of performance, the commission may adopt a design, equipment, 

material, work practice or operational standard, or combination of those standards in order to 

55
establish reasonably available control technology or the lowest achievable emission rate in 

nonattainment areas, or in order to establish best available control technology in areas subject 

to prevention of significant deterioration review, or in order to adopt the emission limitations 

promulgated by the administrator of the United States environmental protection agency under 

section 111 or 112 of the federal Clean Air Act as amended through January 1, 1991.

(2) If a person establishes to the satisfaction of the commission that an alternative means of 

emission limitation will achieve a reduction in emissions of an air pollutant at least equivalent to 

the reduction in emissions of the air pollutant achieved under the design, equipment, material, 

work practice or operational standard, the commission shall amend its rules to permit the use of 

the alternative by the source for purposes of compliance with this paragraph with respect to the 

pollutant.

(3) A design, equipment, material, work practice or operational standard promulgated under 

this paragraph shall be promulgated in terms of a standard of performance when it becomes 

feasible to promulgate and enforce the standard in those terms.

(4) For the purpose of this paragraph, the phrase “not feasible to adopt or enforce a standard of 

performance” refers to a situation in which the commission determines that the application of 

measurement methodology to a particular class of sources is not practicable due to 

technological or economic limitations.

b. If the maximum standards for the emission of sulfur dioxide from solid fuels have to be reduced in an 

area to meet ambient air quality standards, a contract for coal produced in Iowa and burned by a facility 

in that area that met the sulfur dioxide emission standards in effect at the time the contract went into 

effect shall be exempted from the decreased requirement until the expiration of the contract period or 

December 31, 1983, whichever first occurs, if there is any other reasonable means available to satisfy 

the ambient air quality standards. To qualify under this subsection, the contract must be recorded with 

the county recorder of the county where the burning facility is located within thirty days after the 

signing of the contract.

c. The degree of emission limitation required for control of an air contaminant under an emission 

standard shall not be affected by that part of the stack height of a source that exceeds good engineering 

practice, as defined in rules, or any other dispersion technique. This paragraph shall not apply to stack 

heights in existence before December 30, 1970, or dispersion techniques implemented before that date.

5. Classify air contaminant sources according to levels and types of emissions, and other characteristics 

which relate to air pollution. The commission may require, by rule, the owner or operator of any air 

contaminant source to establish and maintain such records, make such reports, install, use and maintain 

such monitoring equipment or methods, sample such emissions in accordance with such methods at 

such locations and intervals, and using such procedures as the commission shall prescribe, and provide 

such other information as the commission may reasonably require. Such classifications may be for 

application to the state as a whole, or to any designated area of the state, and shall be made with 

special reference to effects on health, economic and social factors, and physical effects on property.

6. a. Require, by rules, notice of the construction of any air contaminant source which may cause or 

contribute to air pollution, and the submission of plans and specifications to the department, or other 

information deemed necessary, for the installation of air contaminant sources and related control 

56
equipment. The rules shall allow the owner or operator of a major stationary source to elect to obtain a 

conditional permit in lieu of a construction permit. The rules relating to a conditional permit for an 

electric power generating facility subject to chapter 476A and other major stationary sources shall allow 

the submission of engineering descriptions, flow diagrams and schematics that quantitatively and 

qualitatively identify emission streams and alternative control equipment that will provide compliance

with emission standards. Such rules shall not specify any particular method to be used to reduce 

undesirable levels of emissions, nor type, design, or method of installation of any equipment to be used 

to reduce such levels of emissions, nor the type, design, or method of installation or type of construction 

of any manufacturing processes or kinds of equipment, nor specify the kind or composition of fuels 

permitted to be sold, stored, or used unless authorized by subsection 4 of this section.

b. The commission may give technical advice pertaining to the construction or installation of the 

equipment or any other recommendation.

7. Commission rules establishing maximum permissible sulfate content shall not apply to an expansion 

of an industrial anaerobic lagoon facility which was constructed prior to February 22, 1979.

8. a. Adopt rules consistent with the federal Clean Air Act Amendments of 1990, Pub. L. No. 101-549, 

which require the owner or operator of an air contaminant source to obtain an operating permit prior to 

operation of the source. The rules shall specify the information required to be submitted with the 

application for a permit and the conditions under which a permit may be granted, modified, suspended, 

terminated, revoked, reissued, or denied. For sources subject to the provisions of Tit. IV of the federal 

Clean Air Act Amendments of 1990, permit conditions shall include emission allowances for sulfur 

dioxide emissions. The commission may impose fees, including fees upon regulated pollutants emitted 

from an air contaminant source, in an amount sufficient to cover all reasonable costs, direct and 

indirect, required to develop and administer the permit program in conformance with the federal Clean

Air Act Amendments of 1990, Pub. L. No. 101-549. Affected units regulated under Tit. IV of the federal 

Clean Air Act Amendments of 1990, Pub. L. No. 101-549, shall pay operating permit fees in the same 

manner as other sources subject to operating permit requirements, except as provided in section 408 of 

the federal Act. The fees collected pursuant to this subsection shall be deposited in the air contaminant 

source fund created pursuant to section 455B.133B, and shall be utilized solely to cover all reasonable 

costs required to develop and administer the programs required by Tit. V of the federal Clean Air Act 

Amendments of 1990, Pub. L. No. 101-549, including the permit program pursuant to section 502 of the 

federal Act and the small business stationary source technical and environmental assistance program

pursuant to section 507 of the federal Act.

b. Adopt rules allowing the department to issue a state operating permit to an owner or operator of an 

air contaminant source. The state operating permit granted under this paragraph may only be issued at 

the request of an air contaminant source and will be used to limit its potential to emit to less than one 

hundred tons per year of a criteria pollutant as defined by the United States environmental protection 

agency or ten tons per year of a hazardous air pollutant or twenty-five tons of any combination of 

hazardous air pollutants.

c. Adopt rules for the issuance of a single general permit, after notice and opportunity for a public 

hearing. The single general permit shall cover numerous sources to the extent that the sources are 

representative of a class of facilities which can be identified and conditioned by a single permit.

57
9. Adopt rules allowing asphalt shingles to be burned in a fire set for the purpose of bona fide training of 

public or industrial employees in fire fighting methods only if a notice is provided to the director 

containing testing results indicating that the asphalt shingles do not contain asbestos. Each fire 

department shall be permitted to host two fires per year as allowed under this subsection.

10. Adopt rules allowing a city to conduct a controlled burn of a demolished building subject to the 

requirements that are in effect for the proper removal of all asbestos-containing materials prior to 

demolition and burning. The rules shall include provisions that a burn site have controlled access, that a 

burn site be supervised by representatives of the city at all times, and that the burning be conducted 

only when weather conditions are favorable with respect to surrounding property. For a burn site 

located outside of a city, the rules shall include a provision that a city may undertake not more than one 

such controlled burn per day and that a burn site be limited to an area located at least six-tenths of a 

mile from any inhabited building. For burn sites located within a city, the rules shall include a provision 

that a city may undertake not more than one such controlled burn in every six-tenths-of-a-mile-radius 

circle in each calendar year. The rules shall prohibit a controlled burn of a demolished building in Cedar 

Rapids, Marion, Hiawatha, Council Bluffs, Carter Lake, Des Moines, West Des Moines, Clive, Windsor 

Heights, Urbandale, Pleasant Hill, Buffalo, Davenport, Mason City, or any other area where area-specific 

state implementation plans require the control of particulate matter.

[C71, §136B.4; C73, 75, 77, 79, 81, §455B.12; 82 Acts, ch 1124, §1] 

C83, §455B.133 

91 Acts, ch 242, §1; 91 Acts, ch 255, §8; 92 Acts, ch 1163, §87 – 89; 93 Acts, ch 137, §3; 94 Acts, ch 1040, §1; 95 

Acts, ch 2, §1; 2002 Acts, ch 1162, §45; 2002 Acts, 2nd Ex, ch 1003, §241, 262; 2004 Acts, ch 1138, §1; 2010 Acts, 

ch 1061, §180

58
455B.134 Director — duties — limitations.

The director shall:

1. Publish and administer the rules and standards established by the commission. The department shall 

furnish a copy of such rules or standards to any person upon request.

2. Provide technical, scientific, and other services required by the commission or for the effective 

administration of this division II and chapter 459, subchapter II.

3. Grant, modify, suspend, terminate, revoke, reissue or deny permits for the construction or operation 

of new, modified, or existing air contaminant sources and for related control equipment, and conditional 

permits for electric power generating facilities subject to chapter 476A and other major stationary 

sources, subject to the rules adopted by the commission. The department shall furnish necessary 

application forms for such permits.

a. No air contaminant source shall be installed, altered so that it significantly affects emissions, or placed 

in use unless a construction or conditional permit has been issued for the source.

b. The condition of expected performance shall be reasonably detailed in the construction or conditional 

permit.

c. All applications for permits other than conditional permits for electric generating facilities shall be 

subject to such notice and public participation as may be provided by rule by the commission. Upon 

denial or limitation of a permit other than a conditional permit for an electric generating facility, the 

applicant shall be notified of such denial and informed of the reason or reasons therefor, and such 

applicant shall be entitled to a hearing before the commission.

d. (1) All applications for conditional permits for electric power generating facilities shall be 

subject to such notice and opportunity for public participation as may be consistent with 

chapter 476A or any agreement pursuant thereto under chapter 28E. The applicant or

intervenor may appeal to the commission from the denial of a conditional permit or any of its

conditions. For the purposes of chapter 476A, the issuance or denial of a conditional permit by 

the director or by the commission upon appeal shall be a determination that the electric power 

generating facility does or does not meet the permit and licensing requirements of the 

commission. The issuance of a conditional permit shall not relieve the applicant of the 

responsibility to submit final and detailed construction plans and drawings and an application 

for a construction permit for control equipment that will meet the emission limitations 

established in the conditional permit.

(2) In applications for conditional permits for electric power generating facilities, the applicant 

shall quantify the potential to emit greenhouse gas emissions due to the proposed project.

e. A regulated air contaminant source for which a construction permit or conditional permit has been 

issued shall not be operated unless an operating permit also has been issued for the source. However, if 

the facility was in compliance with permit conditions prior to the requirement for an operating permit 

and has made timely application for an operating permit, the facility may continue operation until the 

operating permit is issued or denied. Operating permits shall contain the requisite conditions and 

compliance schedules to ensure conformance with state and federal requirements including emission 

59
allowances for sulfur dioxide emissions for sources subject to Tit. IV of the federal Clean Air Act 

Amendments of 1990. If construction of a new air contaminant source is proposed, the department may 

issue an operating permit concurrently with the construction permit, if possible and appropriate.

f. (1) Notwithstanding any other provision of division II of this chapter or chapter 459,

subchapter II, the following siting requirements shall apply to anaerobic lagoons and earthen

waste slurry storage basins:

(a) Anaerobic lagoons, constructed or expanded on or after June 20, 1979, but prior to May 31, 

1995, or earthen waste slurry storage basins, constructed or expanded on or after July 1, 1990, 

but prior to May 31, 1995, which are used in connection with animal feeding operations 

containing less than six hundred twenty-five thousand pounds live animal weight capacity of 

animal species other than beef cattle or containing less than one million six hundred thousand 

pounds live animal weight capacity of beef cattle, shall be located at least one thousand two 

hundred fifty feet from a residence not owned by the owner of the feeding operation or from a 

public use area other than a public road. Anaerobic lagoons or earthen waste slurry storage 

basins, which are used in connection with animal feeding operations containing six hundred 

twenty-five thousand pounds or more live animal weight capacity of animal species other than 

beef cattle or containing one million six hundred thousand pounds or more live animal weight 

capacity of beef cattle, shall be located at least one thousand eight hundred seventy-five feet 

from a residence not owned by the owner of the feeding operation or from a public use area 

other than a public road. For the purpose of this paragraph the determination of live animal 

weight capacity shall be based on the average animal weight capacity during a production cycle 

and the maximum animal capacity of the animal feeding operation.

(b) Anaerobic lagoons which are used in connection with industrial treatment of wastewater 

where the average wastewater discharge flow is one hundred thousand gallons per day or less 

shall be located at least one thousand two hundred fifty feet from a residence not owned by the 

owner of the lagoon or from a public use area other than a public road. Anaerobic lagoons 

which are used in connection with industrial treatment of wastewater where the average 

wastewater discharge flow is greater than one hundred thousand gallons per day shall be 

located at least one thousand eight hundred seventy-five feet from a residence not owned by 

the owner of the lagoon or from a public use area other than a public road. These separation 

distances apply to the construction of new facilities and the expansion of existing facilities.

(2) A person may build or expand an anaerobic lagoon or an earthen waste slurry storage basin 

closer to a residence not owned by the owner of the anaerobic lagoon or to a public use area 

than is otherwise permitted by subparagraph (1) of this paragraph, if the affected landowners 

enter into a written agreement with the anaerobic lagoon owner to waive the separation 

distances under such terms the parties negotiate. The written agreement becomes effective 

only upon recording in the office of the recorder of deeds of the county in which the residence is 

located.

g. All applications for construction permits or prevention of significant deterioration permits shall 

quantify the potential to emit greenhouse gas emissions due to the proposed project.

4. Determine by field studies and sampling the quality of atmosphere and the degree of air pollution in 

this state or any part thereof.

60
5. Conduct and encourage studies, investigations, and research relating to air pollution and its causes, 

effects, abatement, control, and prevention.

6. Provide technical assistance to political subdivisions of this state requesting such aid for the 

furtherance of air pollution control.

7. Collect and disseminate information, and conduct educational and training programs, relating to air 

pollution and its abatement, prevention, and control.

8. Consider complaints of conditions reported to, or considered likely to, constitute air pollution, and 

investigate such complaints upon receipt of the written petition of any state agency, the governing body 

of a political subdivision, a local board of health, or twenty-five affected residents of the state.

9. Issue orders consistent with rules to cause the abatement or control of air pollution, or to secure 

compliance with permit conditions. In making the orders, the director shall consider the facts and 

circumstances bearing upon the reasonableness of the emissions involved, including but not limited to, 

the character and degree of injury to, or interference with, the protection of health and the physical 

property of the public, the practicability of reducing or limiting the emissions from the air pollution 

source, and the suitability or unsuitability of the air pollution source to the area where it is located. An 

order may include advisory recommendations for the control of emissions from an air contaminant 

source and the reduction of the emission of air contaminants.

10. Encourage voluntary cooperation by persons or affected groups in restoring and preserving a 

reasonable quality of air within the state.

11. Encourage political subdivisions to handle air pollution problems within their respective jurisdictions.

12. Review and evaluate air pollution control programs conducted by political subdivisions of the state 

with respect to whether the programs are consistent with the provisions of division II of this chapter and 

chapter 459, subchapter II, and rules adopted by the commission.

13. Hold public hearings, except when the evidence to be received is confidential pursuant to section 

455B.137, necessary to accomplish the purposes of division II of this chapter and chapter 459, 

subchapter II. The director may issue subpoenas requiring the attendance of witnesses and the 

production of evidence pertinent to the hearings. A subpoena shall be issued and enforced in the same 

manner as in civil actions.

14. Convene meetings not later than June 1 during the second calendar year following the adoption of 

new or revised federal ambient air quality standards by the United States environmental protection 

agency to review emission limitations or standards relating to the maximum quantities of air 

contaminants that may be emitted from any air contaminant source as provided in section 455B.133, 

subsection 4. By November 1 of the same calendar year, the department shall submit a report to the 

governor and the general assembly regarding recommendations for law changes necessary for the 

attainment of the new or revised federal standards.

[C71, §136B.4, 136B.5; C73, 75, 77, 79, §455B.12, 455B.13; C81, §455B.13; 82 Acts, ch 1124, §2, 3]

C83, §455B.134

61
86 Acts, ch 1245, §1899; 90 Acts, ch 1153, §2, 3; 91 Acts, ch 255, §11 - 13; 93 Acts, ch 137, §4; 95 Acts, ch 195, §14; 

2007 Acts, ch 120, §2, 3; 2010 Acts, ch 1115, §1; 2011 Acts, ch 25, §49, 50

For regulations establishing separation distances between anaerobic lagoons or earthen manure storage structures 

constructed or expanded on or after May 31, 1995, and various locations and objects, see chapter 459

For regulations governing the construction of earthen storage structures within agricultural drainage well areas, 

see chapter 460

Subsection 3, paragraph d, subparagraph (2) amended

Subsection 3, paragraph g amended 

62
567 Iowa Administrative Code Chapters for Air Quality

Chapters 20-29, 31, and 33-34 of 567 Iowa Administrative Code contain the administrative rules that 

allow for the implementation of the relevant air quality laws contained in Iowa statute and the CAA, 

including Section 110. 

• Chapter 20 provides general definitions and rules of practice. 

• Provisions for compliance schedules are found in Chapter 21. 

• Standards and procedures for the permitting of emission sources, periodic monitoring, and 

requirements for nonattainment areas are found in Chapter 22. 

• Air emission standards for contaminants are found in Chapter 23. 

• Chapter 24 provides for the reporting of excess emissions and the equipment maintenance and 

repair requirements. 

• Testing and sampling requirements for new and existing sources are found in Chapter 25. 

• Chapter 26 identifies air pollution emergency episodes and preplanned abatement strategies. 

• Conditions that political subdivisions must meet in order to secure acceptance of a local air 

pollution control program are set forth in Chapter 27. 

• Chapter 28 identifies the state’s adopted ambient air quality standards. 

• Qualifications for observers of visible emission are found in Chapter 29. 

• Chapter 31 contains the conformity of general federal actions to the Iowa state implementation 

plan or federal implementation plan. 

• Chapter 33 contains special regulations and construction permit requirements for major 

stationary sources and includes the requirements for PSD. 

• Provisions for air quality emissions trading programs are found in Chapter 34.

63