OPPD-Nebraska City Station-58343r04.doc 

Response Summary-Page 1

RE: RESPONSE SUMMARY 

 Omaha Public Power District 

 444 South 16th Street Mall 

 Omaha, NE 68102-2608 

(NDEQ Facility #58343-Nebraska City Station #1) 

To Whom It May Concern: 

The Department has considered all comments received and has made a final decision to issue the 

Prevention of Significant Deterioration and Best Available Retrofit Technology Construction Permit to 

Omaha Public Power District for Unit 1 at the Nebraska City Station. This Permit is approved in 

accordance with regulations contained in Title 129 - Air Quality Regulations. 

The decision regarding issuance of this Construction Permit may be appealed under Neb. Rev. Stat. 81-

1509. This appeal shall be done in accordance with the Administrative Procedure Act, Neb. Rev. Stat. 

Section 84-901 to 84-920 and Title 115 - Rules of Practice and Procedure. 

In preparing this summary, the Department reviewed comments made during the public comment period 

from December 12, 2008, to January 24, 2009, and listed significant comments in the attached 

Responsiveness Summary. The Responsiveness Summary consists of four sections: 

Comment #: The comment is summarized. 

Response and Rationale: Department’s response to the comment raised and the rationale. 

Changes: Any changes to the Permit and/or Fact Sheet are addressed. 

Applicable Regulations/Statutes: This is a listing of regulations/statutes pertinent to the comment. 

The Department appreciates the time and the conscientious efforts of all that have commented. If you 

have any questions, please contact Shelley Kaderly, Air Quality Division Administrator, or me at (402) 

471-2186. 

Sincerely, 

 {Original Signed} 2/26/09 

_____________________________________________ ____________________________ 

Jay D. Ringenberg Date 

Deputy Director for Programs 

Enclosure 
OPPD-Nebraska City Station-58343r04.doc 

Response Summary-Page 2

Background Information:

Omaha Public Power District (OPPD) submitted a Prevention of Significant Deterioration (PSD) and 

Best Available Retrofit Technology (BART) Construction Permit application on August 8, 2007 for Unit 

1 at their Nebraska City Station (NCS #1). Additional information was received on December 4, 2007, 

and in November 2008. This permit approves the installation of emission controls in accordance with 

Title 129 to comply with BART requirements and to permit the increase of other pollutants that may 

increase as a result of the installation of BART controls. The draft permit and materials were made 

available on the NDEQ website. Nearby states with Class I areas, federal land managers, and other 

interested parties were notified of the availability of the draft permit. The initial comment period was 

originally extended by two weeks to January 24, 2009, at the request from EPA Region VII. 

 

Becky Weber, Division Director of the Air & Waste Management Division of the U.S. Environmental 

Protection Agency Region VII Office in Kansas City, KS submitted comments on January 23, 2009. No 

other comments were received. The following are NDEQ’s responses to the EPA comments received 

during the public comment period: 

COMMENT #1: 

EPA made several comments on the fact sheet related to obligations under the Regional Haze Rule. In 

order to address them, NDEQ has separated the issues into separate comments to make the NDEQ 

responses clear. 

EPA noted that the State has additional obligations to address in its Regional Haze State Implementation 

Plan (SIP) besides just the application of Best Available Retrofit Technology (BART) on BART-subject 

sources. These additional obligations are identified in 40 CFR 51.308. EPA was concerned that the fact 

sheet implied the application of BART was Nebraska’s only obligation to specifically include in the 

Regional Haze SIP. 

RESPONSE AND RATIONALE: 

EPA is correct; the Nebraska State Implementation Plan for Regional Haze must address specific items 

that are identified in 40 CFR 51.308(d) and (e). However, the primary purpose of the permitting action is 

to make a Best Available Retrofit Technology Determination for Omaha Public Power District’s 

Nebraska City Unit 1 in accordance with Title 129 Nebraska Air Quality Regulations (NAQR) Chapter 

43 – Visibility Protection and Chapter 17 – Construction Permits: When Required. The BART 

permitting action will become a part of the overall Nebraska Regional Haze SIP. 

CHANGES: None 

APPLICABLE REGULATIONS: Title 129 NAQR Chapter 17; Chapter 43 

COMMENT #2: 

EPA raised concerns that states, such as Missouri, were relying on presumptive levels of SO2 to be 

achieved at the Nebraska City Unit 1 (NCS #1) plant in order to achieve their reasonable further progress 

goals. EPA held that installation of presumptive level controls at NCS #1 was assumed in IPM modeling 

supporting the Clean Air Interstate and Clean Air Mercury Rules. EPA further held that work done by 

the Central Regional Air Planning Association (CENRAP) used these same assumptions in forming the 

basis for regional haze SIPs submitted by states such as Missouri. EPA is concerned that the assumptions 

for NCS #1 in the CENRAP work led EPA to decide on regional scale boundaries for CAIR modeling, 

and that other states are relying on Nebraska to achieve the assumed SO2 reductions at NCS #1 in order 
OPPD-Nebraska City Station-58343r04.doc 

Response Summary-Page 3

to meet their own State’s visibility goals. EPA notes that under 40 CFR 51.308(d)(3)(ii), the State must 

ensure that it has included all measures needed to achieve its apportionment of emissions reduction 

obligations agreed upon through the regional planning process.

RESPONSE AND RATIONALE: 

The most significant visibility impacts to Class I areas from NCS #1 are on Hercules Glades (MO) and 

Wichita Mountains (OK) (Refer to Table 2 of the Fact Sheet). As indicated in the Fact Sheet, neither 

Missouri nor Oklahoma identified the need for SO2 emission reductions from Nebraska at this time. 

Both states were provided an opportunity to comment on this BART permitting action, and neither raised 

issues with the proposed action. Furthermore, NDEQ’s conclusion is supported by work that has been 

done by CENRAP. 

Areas of influence and apportionment of Nebraska’s SO2 emissions were evaluated in the August 31, 

2005, Causes of Haze Study conducted by Sonoma Technology, Inc. This study may be found on 

CENRAP’s website (www.cenrap.org). Sonoma concluded that because the emission impact potentials 

(EIPs) of potentially BART-eligible sources are relatively small, the enforcement of BART requirements 

will produce limited improvement in visibility conditions and require the need for additional emission 

reduction strategies. Emission impact potentials relate the probability of transport of SO2 and NOx 

pollution from an area such as a state to a Class I area and the scale of emissions in that given area 

(State). In Figures 4-8 and 4-9 of the study, Nebraska BART sources have an insignificant EIP, 

specifically for the Hercules Glades Class I area. 

In a paper written by Sonoma Technology and Brett Anderson (EPA Region 7) (see Appendix D of the

paper), the composition of particles were studied in an effort to better understand how to improve the 

visibility for the Hercules Glades Class I area. The results showed that sulfate accounted for 65% of the 

mass at Hercules Glades and most of the sulfate was in the form of ammonium sulfate. The paper 

reported that it “was highest on days with transport from the Ohio River area, where many coal-fired 

power plants are located and which has been identified as a significant area for the origin of sulfate 

transport.” Sonoma and Anderson went on to say that the EIP analysis corroborated this, showing that 

more than half of the SO2 came from that particular area, and that when looking at the county-level, it 

was clear that a handful of sources in a few counties were responsible for most of the SO2 emissions 

impacting Hercules Glades. However, the study revealed that ammonium nitrate showed strong seasonal 

tendencies. It was highest during the winter, and was highest under conditions of slow moving cool air 

masses from northwest Missouri, Iowa, Nebraska, and Kansas. 

Nebraska participated in the CENRAP regional planning process. However, it is important to note that 

CENRAP recognizes the authority and jurisdiction of each state and tribal member. Nebraska also was 

invited to participate in a limited capacity in a consultation process with Missouri and Oklahoma, which 

is a part of the regional planning process. The burden to request emission reductions from Nebraska is 

on the state with the Class I area in need of visibility improvement. We provided Missouri, Oklahoma, as 

well as other surrounding states the opportunity to comment on the BART permit for NCS #1. We did 

not receive any comments from any states. We believe that by controlling NOx emissions, Nebraska is 

ensuring that it is including all measures needed to achieve its apportionment of emissions reduction 

obligations identified through the regional planning process. 

CHANGES: None 

APPLICABLE REGULATIONS: Title 129 NAQR Chapter 43; 40 CFR 50.308 
OPPD-Nebraska City Station-58343r04.doc 

Response Summary-Page 4

COMMENT #3: 

EPA expressed it’s belief that it is a reasonable interpretation that if the units are in existence and the 

plant is greater than 750 MW at the time the BART determination is made by the state, then any unit at 

the plant greater than 200 MW is subject to presumptive BART. 

RESPONSE AND RATIONALE: 

NDEQ does not agree with EPA. It is arbitrary to use NCS #2 to make NCS #1 >750MW. NCS #1 was 

built during the BART timeframe (1962-1977). OPPD applied for a Prevention of Significant 

Deterioration permit on February 23, 2004, for the construction of NCS #2 which was issued in March 

2005. 

NDEQ conducted a careful review of the June 2005 “Regulatory Impact Analysis for the Final Clean Air 

Visibility Rule or the Guidelines for Best Available Retrofit Technology (BART) Determinations under 

the Regional Haze Regulations” (RIA), the Federal Register July 2005 final preamble, and the rule. 

These documents provide clarification as to how EPA intended for states to aggregate multiple units at a 

power plant in order to determine whether the 750 MW threshold is crossed. 

First, in the preamble to the July 6, 2005, Regional Haze/BART rule, on page 39112, middle column, 

EPA states: 

“Finally, the approach to identifying a “BART-eligible source” in the guidelines is based on the 

definitions in the regional haze rule of the relevant terms. For 750 MW power plants, States are 

required to apply the definitions as set forth in the guidelines; for other sources, States may 

adopt a different approach to the task of identifying BART eligible sources, so long as that 

approach is consistent with the ACT and the implementing regulations. In other words, while the 

guidelines adopt an approach for large power plants which involves the aggregation of all 

emission units put into place between 1962 and 1977 (emphasis added), States have the 

flexibility to consider other reasonable approaches to the question of identifying BART-eligible 

sources for other source categories.” 

It seems clear from this language that EPA’s intent was for individual electrical generation units that 

were put into place between 1962 and 1977 be aggregated for purposes of determining whether a power

plant meets the 750 MW capacity threshold for applying presumptive-level BART. 

Furthermore, Appendix B of the RIA includes a memo from Perrin Quarles Associates, Inc (PQA) dated 

July 19, 2004. The memo provides a summary of the analysis PQA conducted for EPA to develop 

supporting materials for the Regional Haze/BART rule. In the memo is a statement that “Based on EPA 

guidance, the original analysis also assumed that BART-eligible units are only those that are located at a 

plant where the total capacity of all units within the BART timeframe exceeds 750MW.” Attached with 

the memo are two tables which include NCS #1 with the listed capacity at around 616 MW. The first 

table also lists much smaller units located in Nebraska that were potentially put into place during the 

BART timeframe (1962 – 1977). The second table includes NCS #1 as a potentially BART-subject 

source, but no-where does the table indicate that the sources on the table are subject to the presumptive 

levels in the guidelines. The reasonable conclusion NDEQ draws from the inclusion of NCS #1 in the 

second table is that NCS #1 could potentially have a contribution to a Class I area above the 0.5 deciview 

threshold on more than one day, triggering the need for further analysis and the potential need for BART 

to be applied to one or more visibility impairing pollutants. 
OPPD-Nebraska City Station-58343r04.doc 

Response Summary-Page 5

EPA’s record supports NDEQ’s determination that it is not appropriate to aggregate the capacity of NCS 

#2 with NCS #1. Therefore, for purposes of the BART program, the OPPD Nebraska City Station is not 

a 750 MW power plant. However, NDEQ does think it is an appropriate decision making methodology 

to apply the five-factor analysis in the process of determining BART. 

CHANGES: None 

APPLICABLE REGULATIONS: NAQR Title 129 Chapter 43; 40 CFR Part 51 

COMMENT #4: 

EPA commented that the burden is on the state to justify that presumptive limits are not appropriate for 

750 MW power plants. They also believe that uncontrolled EGUs greater than 200 MW in size, but

located at power plants smaller than 750 MW, are generally cost effective to control and provide 

significant visibility improvement. EPA Region 7 believes controls for SO2 are within the range of being 

cost effective on a $/ton reduced basis. 

RESPONSE AND RATIONALE: 

As stated in the response to Comment #3, Nebraska City Station Unit #1 is not a 750 MW power plant 

for purposes of the BART program. 

EPA, in the preamble to the July 6, 2005, rule stated that based on their analysis, they generally believe 

that states will find the same presumptive level controls to be highly cost-effective, and to result in a 

significant degree of visibility improvement, for most EGUs greater than 200 MW, regardless of the size 

of plant at which they are located. The preamble goes on to declare that the state is free to reach a 

different conclusion if the state believes that an alternative determination is justified based on a 

consideration of the five statutory factors. Those five factors are: 1) costs of compliance; 2) energy and 

non-air quality environmental impacts of compliance; 3) existing pollution control technology at the 

source; 4) remaining useful life of the source and 5) degree of improvement in visibility which may 

reasonably be anticipated. 

After careful analysis using the five statutory factors, NDEQ has reached its conclusion that imposing 

additional SO2 controls onto NCS #1 is not cost-effective considering: the compliance costs; impact to 

and distance from Class I areas; and, the degree of visibility improvement which may reasonably be 

anticipated. 

EPA’s “Technical Support Document: Setting BART SO2 Limits for Electric Generating Units: Control 

Technology and Cost Effectiveness” does include NCS #1 in a spreadsheet which appears to indicate 

EPA thought that approximately $830 per ton of SO2 reduction was cost effective (on average) for EGUs 

approximately the same size as NCS #1. 

At the “presumptive levels” for SO2 (0.15 lb/MMBtu), OPPD estimated SO2 controls to be about $1760 

per ton of SO2 removed. At the lower level of 0.1 lb/MMBtu, OPPD estimated costs to be $1635 per ton 

of SO2 removed. The values OPPD derived ended up being double the values EPA estimated when 

promulgating the rule. This is even despite the fact that when OPPD calculated their values they used a 

pre-control SO2 value of 0.815 lb/MMBtu, which was the maximum actual 24-hr SO2 emissions rate 

during 2001 – 2003. If OPPD used the pre-control SO2 value EPA assumed during rule promulgation, 

0.61 lb/MMBtu, and still achieved the presumptive level of 0.15 lb/MMBtu or 0.1 lb/MMBtu, the $/ton 

would increase: 
OPPD-Nebraska City Station-58343r04.doc 

Response Summary-Page 6

Emission Rate Tons SO2 $/Ton 

0.61 lb/MMBtu (pre-control 

from EPA assumptions) 

18,107 ---- 

0.15 lb/MMBtu 4,452 $2,543 

0.1 lb/MMBtu 2,968 $2,293 

It would appear that OPPD’s $/ton costs are between 2-3 times what EPA anticipated when promulgating 

the rule. EPA did provide a $/ton value in the rule for non presumptive EGU units. While this may still 

be considered cost effective from a $/ton reduced perspective if the New Source Review program were 

being implemented, the program being implemented is Visibility Improvement. NDEQ is concerned that 

the $/ton values are 2-3 times higher than EPA anticipated, but also the decisions made on control 

technologies through this program need to be cost effective in terms of yielding visibility improvement. 

CHANGES: None 

APPLICABLE REGULATIONS: Title 129 NAQR Chapter 17; Chapter 43 

COMMENT #5: 

EPA is concerned that NDEQ is using solely dollars per deciview ($/dV) as a decision-making metric for 

BART. They list four concerns: 1) they believe that although the EPA BART guidelines allow for its 

use, there are significant difficulties in developing a meaningful method for calculating $/dV; 2) they 

believe it should only be used as a supplement to $/ton, in evaluating cost effectiveness; 3) they believe 

cost estimates must be reasonable, and recommends that cost estimates be based upon the OAQPS Cost 

Manual; and 4) they believe that even when used as a supplement to $/ton, the $/dV analysis would be 

meaningless if it does not take into account visibility impacts at multiple Class I areas or ignores the total 

improvement (frequency, magnitude, and duration of the modeled changes in visibility). 

RESPONSE AND RATIONALE: 

NDEQ would like to clearly state that it did not rely solely on one factor in making its SO2 BART 

determination for NCS #1, but rather, considered all five factors. Furthermore, the EPA’s citation of the 

$/dV metric as only one factor is mistaken, since by definition, this calculated ratio includes both the cost 

and the benefit (degree of visibility improvement). The other three factors (the energy and non-air 

quality environmental impacts of compliance, any existing pollution control technology in use at the 

source, the remaining useful life of the source) were also considered in the five-factor analysis. 

Therefore, Nebraska has indeed considered all five factors and has not relied on a single factor in its SO2

BART determination. 

The Clean Air Act, Section 169A(g)(2) states: 

“in determining best available retrofit technology the State (or the Administrator in determining 

emission limitations which reflect such technology) shall take into consideration the costs of 

compliance, the energy and non-air quality environmental impacts of compliance, any existing 

pollution control technology in use at the source, the remaining useful life of the source, and the 

degree of improvement in visibility which may reasonably be anticipated to result from the use of 

such technology” 
OPPD-Nebraska City Station-58343r04.doc 

Response Summary-Page 7

EPA’s initial Regional Haze rules had directed states to set BART emissions limits based on only the 

first four factors listed in the above statutory language, after determining that a given source was 

“subject” to BART. Thus, EPA had initially left the visibility improvement factor out of the BART 

determination step. In the case of American Corn Growers Assn v. EPA (291 F.3d 1; D.C. Cir., 2002), 

the court sided with the American Corn Growers Association, and ruled that all five factors, including the 

“degree of visibility improvement” needed to be considered in the BART determination. EPA 

subsequently revised the Regional Haze rules accordingly, on July 6, 2005. 

The next paragraphs address the other concerns identified by EPA. 

When OPPD prepared the cost analysis, the January 2002 OAQPS Control Cost Manual was generally 

followed. OPPD supplemented, where possible, information they were supplied by vendors in 2003 

when the NCS #2 was permitted. 

Costs to retrofit are unique to the specific unit, its current design, and site layout, making retrofit costs 

exceed those of building a new unit. There may be significant mechanical, structural, and electrical 

changes and upgrades needed to accommodate a retrofit. Sargent and Lundy (S&L) evaluated FGD 

technology and costs on electric generating units as part of a study for the National Lime Association in 

March 2007. The study is titled “Flue Gas Desulfurization Technology Evaluation: Dry Lime vs. Wet 

Limestone FGD.” S&L evaluated 36 cases, including retrofits. While the authors caution against using 

the information for planning the cost of an FGD project, NDEQ used this information for comparison 

purposes. Overall, the capital costs provided by OPPD were approximately 45% higher than those in the 

S&L study. There appear to be several reasonable explanations for why this is the case: 1) OPPD 

provided costs for control of a 650 MW unit whereas the S&L study only provided retrofit information 

on 400MW and 500MW units; 2) OPPD added 10% for “turnkey services” for purposes of engineering 

design and construction management; and 3) As S&L stated in the study, FGD prices have seen a 

minimum of 25% inflation in 2006. Some recent contracts have been signed at prices over 300% higher 

than the market of 5 years ago. Therefore, the statements made by EPA that the costs of FGD have gone 

down appear to have seen a reverse trend with the marked increase in demand. Although OPPD’s costs 

are higher, the $/ton SO2 removed was about the same as those in the S&L study. 

All of the above considered, the NDEQ determined that the costs presented by OPPD were reasonable. 

The 40 CFR Part 50 Appendix Y BART Guidelines provide for in the “Costs of Compliance” provide for 

several cost effectiveness measures including incremental cost effectiveness in $/ton and other measures 

like $/dV. In the BART program, Appendix Y is putting the cost of the control into perspective by 

allowing for consideration of the goal of the program, which is visibility improvement. Sources with a 

significant baseline impact to a Class I area will likely have much lower cost per deciview of visibility 

improvement when controls are employed. Using a $/dV metric also indirectly takes into consideration 

the distance a source is from the Class I area. Assuming they are upwind, similar size emission sources 

located different distances away from a given Class I area would be expected to have different impacts 

on that Class I area. 

Appendix Y provides “If the highest modeled effects are observed at the nearest Class I area, you (the 

State) may choose not to analyze the other Class I areas any further as additional analyses might be 

unwarranted.” It is reasonable to expect that benefits seen at the nearest Class I area would be less 

pronounced at Class I areas further distances away. In this case, the nearest Class I area is Hercules 
OPPD-Nebraska City Station-58343r04.doc 

Response Summary-Page 8

Glades in Missouri. Logic would conclude that our proposed action (no additional SO2 control on NCS 

#1) would not result in further degradation to a Class I area. 

The total baseline impact from NCS #1 is shown in Table 2 of the Fact Sheet. The number of days above 

0.5 dV for the 7 Class I areas analyzed ranged from 0 – 14 days. The areas with the highest number of 

days were Hercules Glades with 14 in 2001, Hercules Glades with 9 in 2002, and Wichita Mountains

with 10 in 2003. These 2 areas were also the only ones with a 98th percentile value above the 0.5 dV 

threshold. The improvements in these areas were evaluated in determining BART. Improvements in the 

other areas may be experienced through additional SO2 controls at NCS #1, however the impact was 

typically 4 days or less. Even if cumulative improvements in visibility from SO2 and NOx controls were 

considered (0.3 dV and 0.437 dV), the $/dV would still be nearly $49 million/dV. ($1,380,000 + 

$34,720,000 = $36,100,000; $36,100,000/0.737 dV = $48,982,361/dV.) This is still significantly higher 

than the incremental cost effectiveness value under consideration in Wyoming at the Wyodak facility 

($16.3 million/dV). In Wyoming, an additional metric was used to put the visibility improvement into 

perspective. The incremental reduction in days above 0.5 dV in each Class I area was evaluated. Using 

that metric for OPPD, and using an average of days over 0.5 dV during 2001 – 2003 annually: 

NOx BART Controls Alone: $276,000/day 

Incremental Cost of adding SO2 Controls with NOx Controls: $3,857,777/day 

Cumulative Cost of NOx and SO2 Controls: $2,578,571/day 

The rule does not provide a level to which individual sources must reduce their visibility impact, leaving 

it up to the state’s judgment. Given what the Causes of Haze Study found where the SO2 emissions were 

coming from and the pathway for NOx emissions from Nebraska, the amount of improvement that is 

expected from the additional NOx controls, the excessive costs for the amount of visibility improvement 

due to additional SO2 controls and the lack of additional inquiry from Missouri or Oklahoma, NDEQ has 

concluded it is most appropriate to implement additional NOx controls as BART for NCS#1. 

CHANGES: None 

APPLICABLE REGULATIONS: Title 129 NAQR Chapter 17; Chapter 43 

COMMENT #6: 

EPA commented that NCS #1 was not compared to other facilities within the same power pool, but 

instead facilities that were not similar to NCS #1. 

RESPONSE AND RATIONALE: 

Prior to public notice and again before issuance of the permit, NDEQ conducted a review of the 

BACT/LAER Clearinghouse for retrofit projects to compare to NCS #1, and to determine whether OPPD 

had adequately supplied all information about such projects in its submittal. EPA did not provide a list 

of any additional known BART decisions within the Mid-Continent Area Power Pool (MAPP). MAPP 

includes the states of Minnesota and North Dakota, which were reflected in the Fact Sheet. Information 

was listed on the WRAP’s website in the MAPP, however, the facilities listed utilize lignite and not 

subbituminous coal similar to OPPD. 

CHANGES: None 
OPPD-Nebraska City Station-58343r04.doc 

Response Summary-Page 9

APPLICABLE REGULATIONS: Title 129 NAQR Chapter 17; Chapter 19; Chapter 43 

COMMENT #7: 

EPA argues that whether the predicted visibility benefits resulting from controls at a source are 

perceptible should not by itself be the determining factor in deciding BART. EPA also commented that 

OPPD would likely achieve lower SO2 emissions than those analyzed (0.15 lb/MMBtu and 0.1 

lb/MMBtu). EPA also suggested that NDEQ consider cumulative dV improvements from multiple 

technologies. 

RESPONSE AND RATIONALE: 

As explained above in response to other comments, NDEQ used the five statutory factors in arriving at 

the BART determination. 

The level of 0.15 lb/MMBtu, which is the presumptive level established by EPA in the rule for 750MW 

and greater plants, was used as an achievable scrubber emission rate. Additionally, NDEQ requested that 

OPPD analyze 0.1 lb/MMBtu, a rate which is significantly lower than the presumptive rate and was 

agreed to by EPA. 

Table 8 of OPPD’s BART submittal shows what cumulative improvements would be for NCS #1 under 

several scenarios for the maximum impacts at Hercules Glades and Wichita Mountains. 

CHANGES: None 

APPLICABLE REGULATIONS: Title 129 NAQR Chapter 17; Chapter 19; Chapter 43 

COMMENT #8: 

EPA commented that while the use of a construction permit may provide for adequate enforceability of 

the BART emission limits, it is recognized that minor changes to permits often occur during construction 

and operation of the units. EPA asserts that if changes were made to the construction permit which 

effects, in any manner, the permit requirements related to the BART emission limits, the source could not 

rely on such changes until NDEQ requested and EPA approved them into the SIP. They also state that 

this restriction applies even if the primary purpose of the permit revision is not to change BART 

obligations. Since there is no discretion to change the limits without a corresponding SIP change, EPA 

suggests that NDEQ may wish to consider utilizing a rulemaking or state enforceable agreement, 

incorporated into and approved as part of the SIP, to ensure the BART emission limits are enforceable. 

RESPONSE AND RATIONALE: 

NDEQ appreciates the suggestion made by EPA, however, as EPA Region 7 is aware, the NDEQ has 

already adopted into Title 129 NAQR Chapter 43 the construction permit program as the mechanism for 

making the BART requirements enforceable. As with the current construction permit program, the 

provisions of Chapter 43 will be submitted as a part of the State Implementation Plan. The current 

construction permit program (Chapter 17) is a part of the State Implementation Plan; therefore any 

permits that are issued in accordance with it should be enforceable. Nebraska will include in its SIP 

submittal, information about the BART permits issued. 

CHANGES: None 
OPPD-Nebraska City Station-58343r04.doc 

Response Summary-Page 10

APPLICABLE REGULATIONS: Title 129 NAQR Chapter 17; Chapter 19; Chapter 43 

COMMENT #9: 

EPA expressed concern about the differences in the timing between the BART rule provisions and the 

PSD permit requirements for purposes of commencing construction. EPA is concerned that OPPD may 

choose to delay construction and suggests that NDEQ require commencing construction within 18 

months of the issuance of the PSD construction permit. 

RESPONSE AND RATIONALE: 

NDEQ understands EPA’s concern. There is the unique situation where the control technology 

determined to be BART requires a PSD permit due to the projected increase in carbon monoxide 

emissions. The BART provisions promulgated by EPA allow sources up to 5 years after SIP approval to 

make BART controls operational and in compliance. While OPPD assures NDEQ their intent is to 

commence construction as soon as practicable after receiving the BART and PSD permits, unforeseen 

circumstances could change those plans. 

The PSD rules (52.21(r)(3)) and Title 129 NAQR Chapter 17, Section 012, allow the NDEQ to grant

extensions of the 18 months timeframe under certain circumstances. In the event that OPPD does not 

commence construction within 18 months of receipt of the permit as planned, NDEQ will work with 

OPPD to ensure that any necessary evaluation of best available control technology for carbon monoxide 

is done. 

CHANGES: None 

APPLICABLE REGULATIONS: Title 129 Chapter 19; 40 CFR 51 

Questions regarding this summary may be directed to:

 Air Quality Division-Permitting Section 

 Nebraska Department of Environmental Quality 

 PO Box 98922 

 Lincoln, NE 68509-8922