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National Park Service and U.S. Fish and Wildlife Service Comments

Nebraska Draft Regional Haze State Implementation Plan (SIP)

January 14, 2011

The National Park Service and Fish and Wildlife Service received Nebraska’s draft regional haze 

state implementation plan (SIP) on November 16, 2010. We appreciate the opportunity to 

review the draft plan. The National Park Service and Fish and Wildlife Service provided 

recommendations to the Nebraska Department of Environmental Quality (NDEQ) in a letter 

dated August 2006 that detailed our priorities in reviewing the state plans. We address those 

priorities in our comments below. We are available to assist NDEQ in addressing our 

recommendations. 

Reasonable Progress

Fundamentally, we are concerned that NDEQ has not met the requirement stated in the Regional 

Haze Rule Section 308(d)(3):

Each State must submit a long-term strategy that addresses regional haze visibility 

impairment for each mandatory Class I Federal area within the State and for each 

mandatory Class I Federal area located outside the State which may be affected by 

emissions from the State. The long-term strategy must include enforceable emissions 

limitations, compliance schedules, and other measures as necessary to achieve the 

reasonable progress goals established by States having mandatory Class I Federal 

areas. 

The draft SIP does not meet this requirement. The reasonable progress goals established by 

South Dakota for Badlands and Wind Cave National Parks, by Colorado for Rocky Mountain 

National Park, by Oklahoma for Wichita Mountains, and by Missouri for Mingo Wildlife Refuge 

and Hercules Glade Wilderness Area, as well as other Class I areas, assume that NDEQ will 

require presumptive BART controls for the Gerald Gentleman and Nebraska City power plants

as modeled by the Western Regional Air Partnership (WRAP) and the Central Regional Air 

Partnership (CENRAP). NDEQ proposes not to require controls of sulfur dioxide (SO2) for any 

of the BART units. NDEQ’s long term strategy does not include the controls required to meet its 

contribution to the reasonable progress goals established by its neighboring states through the 

RPO process. 

Point source SO2 emissions account for 78% of total SO2 emissions in Nebraska’s 2002 

inventory. Electric generating units (EGU) account for 92% of point source SO2 emissions. 

Section 8.3.1.3 indicates that the 2018 inventory assumes significant reductions in SO2 from 

electric generating units based on assumptions of the Integrated Planning Model. NDEQ does 

not document any actual SO2 controls. It can be inferred that no reductions in SO2 emissions 

from point sources are expected and that, based on Tables 8.1 and 8.3, SO2 emissions from 

Nebraska in 2018 are underestimated by 21,218 tons, or 25% in the CENRAP and WRAP 2018 

modeling. Nebraska does not discuss this discrepancy in Chapter 11 when presenting results of 

the 2018 source apportionment modeling or 2018 visibility projections for Class I areas. 
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EPA Region 6 in its proposed Federal Implementation Plan for San Juan Generating Station cites 

the emissions assumptions used in the WRAP modeling as evidence that San Juan Generating 

Station should be required to meet those emissions limits to support the reasonable progress 

goals set by neighboring states for their Class I areas. Similarly, Nebraska should require SO2

controls consistent with the emissions assumptions used in the CENRAP and WRAP modeling 

and used by neighboring states, particularly Colorado and South Dakota, in setting reasonable 

progress goals for their Class I areas. 

Best Available Retrofit Technology (BART)

We have several concerns with the BART analyses for Nebraska City Unit 1 and Gerald 

Gentleman Units 1 and 2. Please include a description of the emissions for the BART eligible 

units. Appendix 10.1 indicates that Gerald Gentleman Units 1 and 2 combined have potential 

SO2 emissions of 79,200 tons/year and Nebraska City Unit 1 has potential SO2 emissions of 

45,696 tons/year. Please confirm and provide the actual annual SO2 emissions from the 2002 

CENRAP inventory for these three units, similar to the nitrogen oxide (NOx) information in 

Table 8.5.

Five Factor Analysis

In Chapter 10, please provide a summary of the five factor analyses for Gerald Gentleman and 

for Nebraska City. The information was very difficult to ascertain from the current discussion in 

Chapter 10. The BART analyses can be summarized in the SIP Narrative and can reference the 

appropriate appendices for further information. 

Step 1: Identify the available retrofit technologies for SO2 and NOx. For SO2 this should 

include lime spray dryer and dry sorbent injection as control options with lower water 

use requirements than wet flue gas desulfurization. For NOx this should include 

selective non-catalytic reduction (SNCR) technology in addition to selective catalytic 

reduction (SCR). 

Step 2: Eliminate technically infeasible options. 

Step 3: Evaluate effectiveness of control options.

Step 4: Evaluate impacts and document results. 

Step 5: Select Best Available Retrofit Control 

Presumptive Controls for Nebraska City 

EPA Region 7 provided guidance to Nebraska in a letter dated January 23, 2009, that the total 

plant capacity (BART plus non-BART units) is to be used to determine if an Electric Generating 

Unit (EGU) is greater than 750 MW and that any units in existence at the time of the BART 

determination are to be included in the total plant capacity. BART units at a facility greater than 

750 MW are subject to presumptive controls. Given that Nebraska City Unit 1 alone is 616 MW, 

Nebraska needs to seriously consider all feasible SO2 control options, and the presumptive SO2

limit, as part of the five factor analysis. The text in Section 10.5 incorrectly refers to Unit 2 as 

BART eligible. Please provide the MW capacity of Units 1 and 2. It is unacceptable that 

Nebraska only discusses the legal requirement for presumptive controls rather than discussing 

the BART analysis and visibility impacts from Unit 1. In Table 10.5, the costs for a scrubber 

are less than $2000/ton and the visibility improvement from a scrubber are close to 0.5dv at a 

single Class I area. If Nebraska considered the visibility benefits at all the affected Class I areas, 
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the benefits of the investment would be greater. Why was dry sorbent injection not evaluated for 

SO2 controls? Why was Selective Non-Catalytic Reduction not evaluated for NOx controls? 

 

Gerald Gentleman

The BART determination is not acceptable as written. We disagree with Nebraska’s BART 

determination of no SO2 controls for Gerald Gentleman. Was dry sorbent injection considered? 

If not, why not? Nebraska provides an elaborate justification that limited water availability 

prohibits the application of wet flue gas desulfurization (FGD) at Gerald Gentleman without 

discussing the viable alternatives that are being used in western states. The economic factors 

influencing the economy of Nebraska are much greater than the possible retirement of irrigated 

acreage to obtain water rights for the power plant. 

The Fish and Wildlife Service’s Nebraska Field Office has reviewed the Nebraska water use 

discussion and has provided the attached comments that Nebraska has overstated the magnitude 

of offset required (see attached comments). 

Additional comments on these two facilities are in the attached documents. 

Additional comments on specific chapters are detailed below.

Chapter 6 Baseline, Current, and Natural Visibility Conditions

Please include summary of baseline conditions at key Class I areas (e.g. Badlands, Hercules 

Glade) impacted by Nebraska emissions to establish the relative contributions of pollutant 

species, seasonal trends in pollutant contributions, and priority for emissions controls. Because 

the Class I areas are geographically distant, the priority for emissions controls may differ among 

the Class I areas. 

Chapter 7 Monitoring Strategy

Measurements at IMPROVE protocol sites and from special studies are discussed but no results 

are presented. How are the ammonia monitoring data being used? 

Chapter 8 Emissions Inventory

The discussion of area source contributions to particulate matter (PM10) in the 2002 inventory is 

good. According to values in Table 8.1, area sources contribute 97% of ammonia (NH3) 

emissions in Nebraska in 2002. Please add for NH3 the same discussion and piechart as 

presented in Figure 8.3 for PM10. We disagree with ignoring NH3 as a contributing pollutant, 

even if it is not a criteria pollutant. Please include a discussion of the change in NH3 in 2018 in 

Table 8.3 and Section 8.3.1.5. 

Please amplify the discussion of the 2018 projections to provide better explanation of the source 

categories contributing to point source emissions of SO2 and NOx. This information was not 

presented in either Appendix 8.2 (SMOKE reports in Microsoft Access) or Appendix 9.1 

(ENVIRON technical report). This information is critical to supporting an adequate reasonable 

progress analysis. 
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Chapter 10 BART

See our general comments above and specific comments in the attached documents. 

Please include the CENRAP BART Modeling Protocol in the Appendices as it has been 

referenced in the BART Modeling Protocol for Gerald Gentleman and Nebraska City. 

Chapter 11 Reasonable Progress/Long Term Strategy

The SIP is missing the required four factor analysis evaluating reasonable control measures for 

sources in Nebraska. 

Table 11.1 reports the net improvement in Light Extinction at neighboring Class I areas based on 

source apportionment modeling and what appear to be incorrect assumptions for SO2 emissions 

in Nebraska. If the emissions assumptions are invalid, Nebraska’s demonstration of reasonable 

progress is also invalid. Nebraska is not achieving the modeled emissions reductions and 

Nebraska’s conclusion that no additional control measures are warranted is not supported. 

Section 11.2: We note that Colorado in its regional haze SIP specifically mentions consultation 

with Nebraska on the BART determination for Gerald Gentleman due to the plant’s impact to 

Rocky Mountain National Park. Nebraska does not include Colorado in its summary. 

South Dakota’s SIP lists a 36% reduction in Nebraska SO2 emissions used in setting reasonable 

progress goals for Badlands and Wind Cave National Parks. This is 23,623 tons lower than we 

infer is appropriate based on no EGU SO2 controls in Nebraska. This disconnect should be 

addressed in consultation with South Dakota and EPA Regions 7 and 8.

Section 11.3.2: Please include discussion about how the visibility improvement goals under the 

regional haze rule are incorporated in Nebraska’s Prevention of Significant Deterioration 

program. 

Section 11.3.7: Nebraska must re-evaluate what reductions are necessary to support the 

reasonable progress goals of neighboring states. The regional haze rule requires that the State 

include in its long term strategy all measures needed to achieve its apportionment of emission 

reductions and to identify all anthropogenic sources of visibility impairment considered in 

developing the long term strategy. Nebraska needs to demonstrate that its emissions sources are 

being controlled and that Nebraska is making reasonable progress in reducing anthropogenic 

emissions.