necessary19. The Jarbidge Wilderness Area is more than 200 km from the proposed project. No 

changes were made to the SIP in response to this comment. 

NGO Comment 3: 

3. The RH SIP does not contain adequate measures under Best Available Retrofit Technology 

(BART) for “BART-eligible” emission units under jurisdiction of the NDEP. 

NDEP Response: 

BART is one component of Nevada’s long-term strategy to meet the national visibility goal. 

Nevada deems our 2018 progress toward the national visibility goal reasonable, both for the 

Jarbidge Wilderness Area and for Class I areas in adjacent states, in part because our 2018 

reasonable progress is better than the 2018 uniform rate of progress. Therefore, Nevada deems 

that the control measures required by Nevada’s BART regulations are adequate. No changes 

were made to the SIP in response to this comment. 

NGO Comment 3, 1st bullet:

• The proposed SO2 BART emission rate for Reid Gardner Units 1, 2, and 3 would actually 

allow for an increase in SO2 emissions above the baseline. By allowing for an emissions 

increase, the Nevada SIP is inconsistent with the regulatory intent of BART. It is proposed 

that Nevada rectify this error by establishing a “two-tiered” BART limit for SO2 emissions 

at Reid Gardner. The current proposed BART limit (0.25 lb/MMBtu) could be applied to a 

short-term (i.e., 1-hour) averaging time, while a more stringent limit (0.10 lb/MMBtu) could 

be established based on a 30-day rolling average. This would allow for short periods of 

higher emissions which appear to be present based on historical data, but would also 

require that the company operate the Reid Gardner SO2 control systems in a manner 

consistent with their historical practice. By following the approach recommended above, the 

annual SO2 emissions from Reid Gardner would not increase and the BART emissions rate 

would more closely align with the “presumptive BART” recommended by EPA. 

NDEP Response: 

Nevada responded to a similar comment from USEPA; see Nevada’s response to USEPA 

Comment 2 in section D.2.2.2.2 of this appendix. The BART SO2 emission limit for all units at 

Reid Gardner was lowered to 0.15 lb/MMBtu, 24-hour average, following the public comment 

period. NDEP expects NV Energy will operate the post-BART Reid Gardner Generating Station

consistent with the highly efficient recent operational history of the facility which has achieved 

the low SO2 emission rates noted by the FLMs. 

No changes were made to Nevada’s RH SIP as a result of this comment. 

NGO Comment 3, 2nd bullet: 

• The proposed NOx BART limit for Reid Gardner Unit 3 is higher at 0.28 lb/MMBtu 

compared to the proposed NOx limit of 0.20 lb/MMBtu for Units 1 and 2. The draft SIP does 

not provide an adequate explanation or justification for why Unit 3 requires a higher NOx

emission rate for BART. 

 

19 http://www.deq.idaho.gov/air/permits_forms/permitting/pcaec/app_f_0408.pdf

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NDEP Response: 

NDEP responded to similar comments from the FLMs as documented in Nevada’s responses in 

Appendix C of this SIP, Comment 13, and in section D.2.2.3.2 of this appendix, Comment 13. 

No changes were made to the RH SIP due to this comment. 

NGO Comment 3, 3rd bullet: 

• The SIP explains that selective catalytic reduction (SCR) was evaluated for potential 

application as BART at Reid Gardner, but rejected based on cost considerations. However, 

it does not appear that NDEP conducted a critical evaluation of the SCR costs supplied by 

NV Energy and instead has accepted the company’s costs “at face value”. If cost is to be 

used as part of the decision to reject SCR as BART for Reid Gardner, the company’s SCR 

cost estimates need to be properly vetted. 

NDEP Response: 

NDEP responded to NPS follow-up comments regarding SCR costs, specifically Comments 7 

and 17 in section 2.2.3.2 if this appendix. NDEP evaluated the significance of these comments 

by conducting additional economic analyses for the three units at the Reid Gardner Generating 

Station under alternative cost and emissions scenarios, as described in NDEP’s response to 

Comment 7. Analyses of the alternative cost scenario data lead NDEP to the same BART 

conclusions NDEP reached during our initial determination, although the alternative cost 

analyses utilized lower costs and greater emissions reductions. 

No changes were made to Nevada’s RH SIP as a result of this comment. 

NGO Comment 3, 4th bullet: 

• The control efficiency used by Nevada in evaluating SCR for Reid Gardner appears to be 

underestimated. In other situations where SCR was reviewed under BART, the post-SCR 

NOx emission rate is consistently 0.07 lb/MMBtu. At Reid Gardner, the proposed post-SCR 

emissions rate ranged from 0.083 to 0.098 lb/MMBtu. The draft SIP does not explain why 

0.07 lb/MMBtu cannot be achieved using SCR at Reid Gardner. If the draft SIP applied a 

more realistic post-SCR emission rate, the cost evaluation for SCR at Reid Gardner would 

be more favorable. 

NDEP Response: 

See NDEP’s response to the NGO comment above. NDEP’s alternative cost analyses for SCR at 

Reid Gardner, discussed above and in NDEP’s response to NPS’ follow-up to Comment 7 in 

section D.2.2.3.2 of this appendix, utilized an emission rate of 0.07 lb/MMBtu. The alternative 

cost analyses indicate that ROFA with Rotamix is NOx BART for Reid Gardner. No changes 

were made to the SIP as a result of this comment. 

NGO Comment 3, 5th bullet: 

• The post-BART modeling for Reid Gardner shows no significant improvement in visibility at 

nearby Class I areas. The lack of improvement in the post-BART modeling reflects the 

failure of the draft SIP to craft a BART proposal that contains any meaningful emissions 

reductions at Reid Gardner, and actually allows for an SO2 emissions increase. If more 

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appropriate BART emission levels were established at Reid Gardner, it is believed that the 

post-BART modeling would show visibility improvement at Grand Canyon and other nearby 

Class I areas. 

NDEP Response: 

Table 5-11 in the SIP presents the pre- and post-BART visibility results modeled by NV Energy 

for Reid Gardner, which show only minor improvements in visibility at the five Class I areas 

with 300 km of the facility. However, the NV Energy modeled emission rates different from

those identified as BART by NDEP, as shown in Table 5-8 of the RH SIP. 

As a result of this comment errors were discovered in Tables 5-4, 5-5, 5-6, 5-7, 5-8 and 7-1, as 

well as Figures 5-2 and 5-3 in the RH SIP which misrepresent the post-BART annual emissions. 

Note that the NDEP post-BART emission limits did not agree between Tables 5-6 and 5-8. The 

corrected values are based on the NDEP baseline emissions, NDEP baseline heat input and 

NDEP BART emission limits. Text in section 5.5 “Summary of BART Control Analyses,” 

section 5.6 “Visibility Improvement Due to BART Implementation,” section 7.2 “BART 

Controls” and section 7.9.1.1 “Major and Minor Stationary Sources” was modified to correct the 

errors and reflect the changes in the tables and figures. 

Corrected Table 5-8 shows the NDEP Reid Gardner BART annual emissions of NOx are 

approximately 57 percent of those modeled, SO2 is 43 percent of those modeled, and PM10 is 57 

percent of those modeled. The total annual post-BART emissions are 50 percent of those 

modeled for Reid Gardner. It is generally recognized that there is a linear relationship between 

modeled emission rates and modeled concentrations when using the CALPUFF modeling 

system. Therefore, it is reasonable to expect that the modeled visibility improvement is 

proportionally greater with the lower NDEP BART emission limits than the results using the 

higher NV Energy modeled limits. NDEP expects significantly greater visibility improvement 

than those presented in Table 5-11 of this SIP. In addition, it is not expected that Reid Gardner 

will operate at BART emission limits 24 hours per day 365 days per year. All hours of Reid 

Gardner operation at SO2 emissions rates less than 0.15 lb/MMBtu will result in additional 

improvements to the modeled visibility. 

In summary, the installation of BART controls at Reid Gardner will result in significant visibility 

improvement at the Grand Canyon and the four other Class I areas within 300 km of the facility. 

In addition, the total annual post-BART emissions from Tracy and Fort Churchill are 50 to 53 

percent of those modeled by NV Energy. NDEP expects significantly greater visibility 

improvement due to the installation of BART than that presented in Tables 5-9 and 5-10 of the 

SIP. No other changes were made to the SIP as a result of this comment. 

NGO Comment 3, 6th bullet: 

• Even after application of BART technologies at Mohave and Reid Gardner, the post-BART 

visibility modeling continues to show that emissions from Mohave and Reid Gardner would 

continue to “cause or contribute” to visibility impairment at nearby Class I areas, including 

Grand Canyon National Park. Nevada should consider more stringent BART emission levels 

that further reduce or eliminate visibility impairment caused by these sources and even 

consider emission reductions that are “beyond BART” as have other states where BART has 

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proven to be ineffective at providing the emission reductions needed to achieve “reasonable 

further progress” toward the national visibility goal. 

NDEP Response: 

Nevada deems our progress toward the national visibility goal reasonable, both for the Jarbidge 

Wilderness Area and for Class I areas in adjacent states. BART is one of the components of 

Nevada’s long-term strategy to meet the national visibility goals. Section 7.9.3.2, “Contributions 

to Impairment at Class I Areas Outside of Nevada,” of Nevada’s RH SIP describes Nevada’s 

evaluation of whether the SIP includes measures necessary to obtain Nevada’s share of 

emissions reductions needed to meet the progress goals in adjacent states. None of the adjacent 

states have contacted Nevada through the consultation process with requests for further 

emissions reductions from Nevada sources as part of measures necessary to meet their 

reasonable progress goals. Since the 2018 reasonable progress goal for Jarbidge Wilderness 

Area exceeds the 2018 uniform rate of progress and other states have not requested Nevada’s 

assistance in meeting their reasonable progress goals, it is not reasonable to require Nevada 

sources to consider emissions reductions beyond BART. 

As noted earlier in our response to NGO Comment 2, 1st bullet, Southern California Edison has 

announced that the Mohave Generating Station will be decommissioned and the generating 

facility will be removed from the site. Therefore, Mohave will no longer impact visibility at any 

Class I area. 

Finally, it is clear from this comment and the supporting text in section 4.3 of the Tech Review, 

that Mr. Gebhart has confused the regional visibility modeling conducted by the WRAP’s 

Regional Modeling Center with the post-BART dispersion modeling for estimating the degree of 

visibility improvement from BART control installation conducted by the facilities. EPA 

guidance and regulation do not require subject-to-BART facilities to install emission-reducing 

control technologies that meet specific visibility criteria. 

The CAA requires states to consider the following five items in identifying BART controls: 1) 

costs of compliance, 2) energy and non-air quality environmental impacts of compliance, 3) 

existing pollution control technology in use at the source, 4) the remaining useful life of the 

source, and 5) the degree of visibility improvement which may reasonably be anticipated from

the use of BART. There is no “cause or contribute” threshold for the post-BART modeling. In 

addition, see NDEP’s response to the NGO comment above regarding the degree of visibility 

improvement resulting from the installation of BART at Reid Gardner. 

No changes were made to the SIP in response to this comment. 

NGO Comment 4: 

4. The RH SIP does not adequately address and mitigate Nevada’s contribution to visibility 

impairment at Class I areas outside of Nevada, in particular National Parks in the southwestern 

United States that are presently known to be adversely impacted by Nevada emissions (i.e., Zion, 

Bryce Canyon, and Grand Canyon National Parks). 

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NDEP Response: 

Please see the response to the preceding NGO comment, which identifies the text in Nevada’s 

RH SIP that describes NDEP’s assessment of the contribution of Nevada emissions to visibility 

impairment at Class I areas in adjacent states. 

Table 4-3 of the SIP presents Nevada’s sulfate extinction contributions to Class I areas outside 

the state, while Table 4-4 presents Nevada’s nitrate extinction contributions to Class I areas 

outside the state. For the worst visibility days, Nevada’s contribution to sulfate extinction is 2.8 

percent at the Grand Canyon, 4.8 percent at Bryce Canyon and 5.6 percent at Zion. For nitrate 

extinction, Nevada’s contribution is 2.8 percent at the Grand Canyon, 8.8 percent at Bryce 

Canyon and 7.9 percent at Zion. 

These contribution results are based on the projected base18b emission inventory, as described in 

section 1.3.2.2 of Nevada’s RH SIP. The base18b inventory does not include any emissions 

reductions resulting from the installation of BART at facilities in Nevada or the rest of the 

WRAP region. However, the base18b inventory does include emissions from a projected 2018 

Future Coal EGU (A), which represents the White Pine Energy Project in this inventory, and 

Mohave Generating Station, as discussed above under Comment 2, 1st bullet. Emissions 

reductions due to the installation of BART at Reid Gardner (reduction of nearly 5,500 tpy NOx 

to 2018 emissions inventory), the dismantling of the Mohave Generating Station (elimination of 

nearly 19,500 tpy NOx and 8,700 tpy SO2 from 2018 inventory), and indefinite postponement of 

permitting/construction of the White Pine Energy Project (elimination of 1,675 tpy NOx and 

1,675 tpy SO2 from 2018 inventory), all located along the eastern boundary of Nevada, suggest 

that visibility impacts due to emissions from Nevada will be reduced at Class I areas in Utah and 

Arizona from those reported above and shown on Figures 1, 2 and 3, below. 

Figures 1, 2 and 3 present the worst days sulfate (top image) and nitrate (bottom image) 2002 

baseline (plan02c emissions inventory) and 2018 projected (base18b emissions inventory) source 

apportionment modeling results for Grand Canyon, Zion, and Bryce Canyon, respectively. 

Figure 1. Source Apportionment Results for Grand Canyon. 

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Figure 2. Source Apportionment Results for Zion. 

Figure 3. Source Apportionment Results for Bryce Canyon. 

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Figures 1, 2 and 3 show the relative contributions to visibility impairment as paired bars for each 

state or source area, the first for the baseline and the second for 2018. These figures also show 

the relative reduction in contribution by each source area from the baseline to 2018. 

Although the Grand Canyon, Zion and Bryce Canyon are not meeting the uniform rate of 

progress for 2018, it is informative to examine each species contribution to visibility impairment. 

Figures 4, 5 and 6 show the contributions to visibility impairment by the individual modeled 

species to these Class I areas. Of particular interest are ammonia nitrate and ammonia sulfate 

extinction, since these species are predominantly due to emissions from anthropogenic sources. 

These figures show that modeling results for these three Class I areas fail to meet the uniform

rate of progress glide slope for nitrate and sulfate, except nitrate at Grand Canyon. 2018 sulfate 

consistently falls approximately 0.5 Mm-1 (0.44 to 0.48 Mm-1) short of the URP glide slope for 

all three areas. Nitrate falls short 0.20 and 0.79 Mm-1 at Bryce Canyon and Zion, respectively. 

However, 2018 nitrate progress at Grand Canyon exceeds the URP glide slope. 

Figure 4. Speciated Contributions to Visibility Impairment at Grand Canyon. 

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Figure 5. Speciated Contributions to Visibility Impairment at Zion. 

Figure 6. Speciated Contributions to Visibility Impairment at Bryce Canyon. 

As per 40 CFR 51.308(d)(1), each state is responsible for establishing goals that provide for 

reasonable progress toward achieving natural visibility conditions for the mandatory Class I 

areas within the state. None of the adjacent states have contacted Nevada with requests for 

further emissions reductions from Nevada sources as part of measures necessary to meet their 

reasonable progress goals. NDEP deems Nevada’s progress toward the national visibility goal 

reasonable, both for the Jarbidge Wilderness Area and for Class I areas in adjacent states. 

No changes were made to the RH SIP as a result of this comment. 

NGO Comment 4, continued:

Regional modeling using the 2018 WRAP inventory projections show that visibility at Grand 

Canyon, Zion, and Bryce Canyon National Parks will not achieve the Uniform Rate of Progress 

(URP) goals and that the “glide path” for visibility improvement to natural conditions by 2064 

will not be achieved without additional emission reductions. This finding occurs even without 

considering that future growth from Nevada coal-fired EGUs appears to be significantly 

underrepresented in the 2018 inventory. As source emissions from within Nevada are shown to 

“cause and contribute” to visibility impairment at Class I areas outside of the state, Nevada 

needs to revisit its draft regional haze SIP and craft an emissions reduction plan that helps 

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achieve the URP goals at Class I areas outside of Nevada. Achieving the national visibility goal 

and meeting the 2018 URP milestones will require aggressive actions from all states in the 

region, including Nevada. Nevada has established BART emission limits in the draft SIP that fail 

to provide meaningful improvement in visibility conditions and that continue to show Nevada’s 

emissions sources will “cause and contribute” to visibility impairment. These findings 

demonstrate that Nevada’s draft regional haze SIP as written fails to meet its primary objective 

of providing the initial step toward meeting the national visibility goal. 

NDEP Response: 

This comment incorporates several of the previous NGO comments. NDEP has addressed 

comments regarding the under-representation of Nevada’s emission inventory, Nevada’s 

visibility impacts at Class I areas in adjacent states, and Nevada’s BART determinations in our 

responses above. Again it appears that the NGOs are not well versed on the differences between 

the BART guidance and the RHR. Cause and contribute is only a criteria to determine whether a 

BART-eligible source will be subject to a full BART determination. Finally, Nevada deems our 

progress reasonable for all Class I areas, both those in adjacent states, as well as the Jarbidge 

Wilderness Area, as stated previously. Nevada projected 2018 reductions of anthropogenic 

emissions are proportional to our contributions to visibility impairment. 

No changes were made to the RH SIP as a result of this comment. 

NGO Comment 5: 

5. There is an inadequate explanation in the RH SIP regarding why the mining and mine 

processing sites were not included in the RH SIP inventory. Please either include these sources 

in the RH inventory or explain why they were excluded. 

NDEP Response:

As the Tech Review states in the last paragraph of page 5: 

“Major industrial emissions inside and outside of Nevada were also considered when 

evaluating visibility conditions at Jarbidge. Within Nevada, major emission sources that 

could affect Jarbidge include the Valmy Station, a coal-fired EGU, along with major gold 

mines and other mineral operations in the state. All of these emissions appear to be 

included in the WRAP emissions inventory relied upon by NDEP for the regional haze

SIP.” Emphasis added by NDEP. 

Since the referenced emission sources are included in the RH SIP inventory as stated in Mr. 

Gebhart’s Tech Review, this comment is spurious and no changes were made to the SIP based on 

this comment. 

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