OPPD-Nebraska City Station-58343r04.doc

Response Summary-Page 1 RE: RESPONSE SUMMARY

Omaha Public Power District

444 South 16 th 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 decisi on to issue the Prevention of Significant Deterioration and Best Available Retrofit Technol ogy Construction Permit to Omaha Public Power District for Unit 1 at the Nebraska City Station. This Per mit 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. R ev. Stat. 81- 1509. This appeal shall be done in accordance with the Administrative Procedure Act, Neb. Re v. 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 c omment 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 hav e commented. If you have any questions, please contact Shelley Kaderly, Air Quality Division Admi nistrator, or me at (402)

471-2186.

Sincerely,

{Original Signed} 2/26/09

_____________________________________________ ____________________________ Jay D. Ringenberg Date Deputy Director for Programs

EnclosureOPPD-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 applicati on on August 8, 2007 for Unit 1 at their Nebraska City Station (NCS #1). Additional information was received on D ecember 4, 2007, and in November 2008. This permit approves the installation of emission controls in accordanc e with Title 129 to comply with BART requirements and to permit the increase of other pollutant s that may increase as a result of the installation of BART controls. The draft permit and ma terials 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 t he U.S. Environmental Protection Agency Region VII Office in Kansas City, KS submitted comments on Ja nuary 23, 2009. No other comments were received. The following are NDEQ’s responses to the EPA com ments received during the public comment period:

COMMENT #1: EPA made several comments on the fact sheet related to obligations under the Regi onal Haze Rule. In order to address them, NDEQ has separated the issues into separate comments to mak e the NDEQ responses clear.

EPA noted that the State has additional obligations to address in its Regional Haze S tate 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 t he fact sheet implied the application of BART was Nebraska’s only obligation to specific ally 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 Regula tions (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 S IP.

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 l evels of SO2 to be achieved at the Nebraska City Unit 1 (NCS #1) plant in order to achieve their reas onable further progress goals. EPA held that installation of presumptive level controls at NCS #1 was ass umed in IPM modeling supporting the Clean Air Interstate and Clean Air Mercury Rules. EPA further hel d that work done by the Central Regional Air Planning Association (CENRAP) used these same ass umptions in forming the basis for regional haze SIPs submitted by states such as Missouri. EPA is concer ned that the assumptions for NCS #1 in the CENRAP work led EPA to decide on regional scale boundaries for CAIR m odeling, and that other states are relying on Nebraska to achieve the assumed SO2 reductions at NCS #1 in orderOPPD-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 emis sions 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 H ercules Glades (MO) and Wichita Mountains (OK) (Refer to Table 2 of the Fact Sheet). As indicated in the Fa ct Sheet, neither

Missouri nor Oklahoma identified the need for SO2 emission reductions from Nebraska a t this time. Both states were provided an opportunity to comment on this BART permitting action, and neit her 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 i n 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, t he enforcement of BART requirements will produce limited improvement in visibility conditions and require the need for addit ional emission reduction strategies. Emission impact potentials relate the probability of tr ansport of SO2 and NOx pollution from an area such as a state to a Class I area and the scale of emissions i n that given area (State). In Figures 4-8 and 4-9 of the study, Nebraska BART sources have an insignific ant 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 im prove the visibility for the Hercules Glades Class I area. The results showed that s ulfate accounted for 65% of the

mass at Hercules Glades and most of the sulfate was in the form of ammonium sulfat e. 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 or igin 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 c ounty-level, it was clear that a handful of sources in a few counties were responsible for most of the S O2 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 i mportant 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 Miss ouri and Oklahoma, which is a part of the regional planning process. The burden to request emission reductions from N ebraska is on the state with the Class I area in need of visibility improvement. We provided Mi ssouri, 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 emi ssions, Nebraska is ensuring that it is including all measures needed to achieve its apportionment of emi ssions reduction obligations identified through the regional planning process.

CHANGES: None

APPLICABLE REGULATIONS: Title 129 NAQR Chapter 43; 40 CFR 50.308OPPD-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 uni ts are in existence and the plant is greater than 750 MW at the time the BART determination is made by the stat e, 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 w as built during the BART timeframe (1962-1977). OPPD applied for a Prevention of Significa nt Deterioration permit on February 23, 2004, for the construction of NCS #2 which was issued in Marc h

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 (B ART) Determinations under the Regional Haze Regulations” (RIA), the Federal Register July 2005 final pre amble, and the rule. These documents provide clarification as to how EPA intended for states to aggrega te 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-eli gible sources for other source categories.”

It seems clear from this language that EPA’s intent was for individual elec trical 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, I nc (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 statem ent that “Based on EPA guidance, the original analysis also assumed that BART-eligible units are only those that are locate d 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 f irst table also lists much smaller units located in Nebraska that were potentiall y put into place during the BART timeframe (1962 – 1977). The second table includes NCS #1 as a potentially BART-subje ct 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 NC S #1 in the second table is that NCS #1 could potentially have a contribution to a Class I area above t he 0.5 deciview threshold on more than one day, triggering the need for further analysis and the potential nee d 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 aggrega te the capacity of NCS #2 with NCS #1. Therefore, for purposes of the BART program, the OPPD Nebraska City Sta tion is not a 750 MW power plant. However, NDEQ does think it is an appropriate decision making methodolog y 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 ar e 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 cont rol and provide significant visibility improvement. EPA Region 7 believes controls for SO2 ar e 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 pla nt for purposes of the BART program.

EPA, in the preamble to the July 6, 2005, rule stated that based on their analysis, they genera lly believe that states will find the same presumptive level controls to be highly cost-ef fective, and to result in a significant degree of visibility improvement, for most EGUs greater than 200 M W, 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 determinati on 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 tec hnology at the source; 4) remaining useful life of the source and 5) degree of improvement in visibil ity which may reasonably be anticipated.

After careful analysis using the five statutory factors, NDEQ has reache d its conclusion that imposing additional SO2 controls onto NCS #1 is not cost-effective considering: the compliance c osts; impact to and distance from Class I areas; and, the degree of visibility improvement whic h may reasonably be anticipated.

EPA’s “Technical Support Document: Setting BART SO2 Limits for Electric G enerating Units: Control Technology and Cost Effectiveness” does include NCS #1 in a spreadsheet which appears t o indicate EPA thought that approximately $830 per ton of SO2 reduction was cost effective (on averag e) 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 whe n promulgating the rule. This is even despite the fact that when OPPD calculated the ir values they used a pre-control SO2 value of 0.815 lb/MMBtu, which was the maximum actual 24-hr SO2 emissions r ate 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 anticipate d when promulgating the rule. EPA did provide a $/ton value in the rule for non presumptive EGU units. While this m ay still be considered cost effective from a $/ton reduced perspective if the New Source Re view program were being implemented, the program being implemented is Visibility Improvement. NDE Q is concerned that the $/ton values are 2-3 times higher than EPA anticipated, but also the decisions made on c ontrol technologies through this program need to be cost effective in terms of yielding vi sibility 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 deci sion-making metric for BART. They list four concerns: 1) they believe that although the EPA BART guideline s allow for its use, there are significant difficulties in developing a meaningful method for cal culating $/dV; 2) they believe it should only be used as a supplement to $/ton, in evaluating cost effectivenes s; 3) they believe cost estimates must be reasonable, and recommends that cost estimates be based upon t he OAQPS Cost Manual; and 4) they believe that even when used as a supplement to $/ton, the $/dV analysis woul d be meaningless if it does not take into account visibility impacts at multiple Cl ass 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 SO 2 BART determination for NCS #1, but rather, considered all five factors. Furthermore, the EP A’s citation of the $/dV metric as only one factor is mistaken, since by definition, this calculated ra tio 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 i n use at the source, the remaining useful life of the source) were also considered in the five-f actor analysis. Therefore, Nebraska has indeed considered all five factors and has not relied on a sing le factor in its SO 2 BART determination.

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

“in determining best available retrofit technology the State (or the Administ rator in determining emission limitations which reflect such technology) shall take into considera tion the costs of compliance, the energy and non-air quality environmental impacts of compliance, any e xisting pollution control technology in use at the source, the remaining useful life of the source, and t he degree of improvement in visibility which may reasonably be anticipated to resul t 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 emiss ions limits based on only the first four factors listed in the above statutory language, after determining t hat a given source was “subject” to BART. Thus, EPA had initially left the visibility improvement fa ctor 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 f actors, including the “degree of visibility improvement” needed to be considered in the BART determina tion. 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 g enerally 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, m aking retrofit costs exceed those of building a new unit. There may be significant mechanical, structural, a nd electrical changes and upgrades needed to accommodate a retrofit. Sargent and Lundy (S&L) evaluat ed FGD technology and costs on electric generating units as part of a study for the National L ime 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 ca ution against using the information for planning the cost of an FGD project, NDEQ used this information for compa rison purposes. Overall, the capital costs provided by OPPD were approximately 45% higher t han those in the S&L study. There appear to be several reasonable explanations for why this is the cas e: 1) OPPD provided costs for control of a 650 MW unit whereas the S&L study only provided retrofit inform ation 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 s een a minimum of 25% inflation in 2006. Some recent contracts have been signed at prices over 300% hig her than the market of 5 years ago. Therefore, the statements made by EPA that the cost s of FGD have gone down appear to have seen a reverse trend with the marked increase in demand. Although OPP D’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 wer e 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 effec tiveness 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 improveme nt. 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 take s 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 Cla ss 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 Cla ss I area is HerculesOPPD-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 day s above 0.5 dV for the 7 Class I areas analyzed ranged from 0 – 14 days. The areas with the highest numbe r 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 98 th percentile value above the 0.5 dV threshold. The improvements in these areas were evaluated in determining BART. I mprovements in the other areas may be experienced through additional SO2 controls at NCS #1, however the impa ct 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 t he Wyodak facility ($16.3 million/dV). In Wyoming, an additional metric was used to put the visibility improve ment into perspective. The incremental reduction in days above 0.5 dV in each Class I area was e valuated. 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 visibili ty impact, leaving it up to the state’s judgment. Given what the Causes of Haze Study found where the SO2 emi ssions 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 visibil ity improvement due to additional SO2 controls and the lack of additional inquiry from Missouri or Oklahoma, N DEQ 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 determ ine whether OPPD had adequately supplied all information about such projects in its submittal. EPA did not prov ide 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 Fac t Sheet. Information was listed on the WRAP’s website in the MAPP, however, the facilities list ed utilize lignite and not

subbituminous coal similar to OPPD.

CHANGES: NoneOPPD-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 cont rols at a source are perceptible should not by itself be the determining factor in deciding BART. EPA also c ommented 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 f rom 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 rul e 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 presumpti ve rate and was agreed to by EPA.

Table 8 of OPPD’s BART submittal shows what cumulative improvements would be for N CS #1 under several scenarios for the maximum impacts at Hercules Glades and Wichita M ountains.

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 enfor ceability of the BART emission limits, it is recognized that minor changes to permits ofte n occur during construction and operation of the units. EPA asserts that if changes were made to the construction per mit which effects, in any manner, the permit requirements related to the BART emission li mits, the source could not rely on such changes until NDEQ requested and EPA approved them into the SIP. They also sta te that this restriction applies even if the primary purpose of the permit revision is not t o change BART obligations. Since there is no discretion to change the limits without a corresponding SI P change, EPA suggests that NDEQ may wish to consider utilizing a rulemaking or state enfor ceable 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, t he NDEQ has already adopted into Title 129 NAQR Chapter 43 the construction permit program as the mec hanism for making the BART requirements enforceable. As with the current construction permi t program, the provisions of Chapter 43 will be submitted as a part of the State Implementation Plan. T he current construction permit program (Chapter 17) is a part of the State Implementation Pl an; 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: NoneOPPD-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 provi sions 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 w ithin 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 technolog y determined to be BART requires a PSD permit due to the projected increase in carbon m onoxide emissions. The BART provisions promulgated by EPA allow sources up to 5 years after S IP 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 pe rmits, 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 O PPD 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