necessary 19 . The Jarbidge W ilderness Area is m o re than 200 km from the proposed project. No changes were m a de to the SIP in response to this comment.

NGO Comment 3: 3. The RH SIP does not contain adequate measur es under Best Available Retrofit Technology (BART) for “BART-eligible” emission units under jurisdiction of the NDEP.

NDEP Response:
BART is one com ponent of Nevada’s long-term st rategy to m eet the national visibility goal.
Nevada deem s our 2018 progress toward the national visibility goal reasonable, both f o r the Jarbidge W ilderness Area and for Class I areas in adjacen t states, in part because ou r 2018 reasonable progress is better than the 2018 uniform rate of progre ss. Therefore, Nevada deem s that the control m easures required by Nevada’s BART regulations are adequate. No changes

were m a de to the SIP in response to this comm ent.

NGO Comment 3, 1 st bullet: • The proposed SO 2 BART emission rate for Reid Gardner Units 1, 2, and 3 would actually

allow for an increase in SO 2 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 SO 2 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 aver age. This would allow for short periods of higher emissions which appear to be presen t based on historical data, but would also require that the company ope rate the Reid Gardner SO 2 control systems in a manner

consistent w ith their historical practice. By following the approach recommended above, the
annual SO 2 emissions from Reid Gardner would not increase and the B ART emissions rate would more closely align with the “presumptive BART” recommended by EPA.

NDEP Response: Nevada responded to a sim ilar comment from USEPA; see Nevada’s response to USEPA

Comm ent 2 in section D.2.2.2.2 of this appendix. The BART SO 2 em issio n lim it f o r all units at Reid Gardner was lowered to 0.15 lb/MMBtu, 24-hour average, following the public comm ent period. NDEP expects NV Energy will operate the post-BART Reid Gardner Generating Station
consistent w ith the highly efficient recent operati onal history of the facility which has achieved
the low SO 2 em ission rates noted by the FLMs.

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

NGO Comment 3, 2 nd bulle t: • The proposed NO

x BART limit fo r Reid Gardner Un it 3 is higher at 0.28 lb/MMBtu compared to the proposed NO

x limit of 0.20 lb/MMBtu for Un its 1 and 2. The draft SIP does not provide an adequate explanation or justif ication for why Unit 3 requires a higher NO

x emission rate for BART.

19 h ttp ://w ww .d eq .id a ho .g ov /air/p erm its_ f o r m s /p erm i t tin g / p c aec/ap p_ f_0 408.pd f

D-141NDEP Response: NDEP responded to sim ilar comm ents from the FLMs as docum ented in Nevada’s responses in Appendix C of this SIP, Comm ent 13, and in section D.2.2.3.2 of this appendix, Comm ent 13.

No changes were m a de to the RH SIP due to this comment.

NGO Comment 3, 3 rd bullet: • The SIP explains that selective catalyti c reduction (SCR) was evaluated for potential

application as BART at Reid Gardner, but reject ed based on cost cons iderations. However, it does not appear that N D EP conducted a critica l evaluation of the SCR costs supplied by NV Energy and instead has accepted the company’s costs “ a t 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 comm ents rega rding 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 econom ic analyses for the three units at the Reid Gardner Generating
Station under alternative cost and em issions sc enarios, as described in NDEP’s response to

Comm ent 7. Analyses o f the alternative cos t scen ario data lead NDEP to the sam e BART conclusions NDEP reached during ou r initial determ ination, although th e alternative co st analyses u t ilized lower costs and greater em issions reductions.

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

NGO Comment 3, 4 th bullet: • The control efficiency used by Nevada in evaluating SCR for Reid Gardner appears to be

underestimated. In other situations w h er e SCR was reviewed under BART, the post-SCR NOx emission rate is consistently 0.07 lb/MMB tu. 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. NDE P’s alternative cost analyses for SCR at Reid Gardner, discussed above and in NDEP’s response to NPS’ follow-up to Comm ent 7 in section D.2.2.3.2 of this appendix, utilized an em i ssion rate of 0.07 lb/MMBtu. The alternative cost analyses indicate that ROFA with Rotam i x is NO

x BART for Reid Gardner. No changes

were m a de to the SIP as a result of this comm ent.

NGO Comment 3, 5 th bullet: • The post-B ART modeling for Reid Gardner show s no significant improvement in visibility at nearby Class I areas. The lack of im provem ent in the post-B ART modeling reflects the failure of the draft SIP to craft a BA RT pr oposal that contains any meaningful emissions reductions at Reid Gardner, and actually allows for an SO 2 emissions increase. If more

D-142appropriate BART emission levels w e re establishe d at Reid G a rdner, it is believed that the post-BART modeling would show visibility im provement at Grand Canyon and other nearby
Class I area s.

NDEP Response: Table 5-11 in the SIP presents the pre- and pos t- BART visibility re su lts modeled by NV Energy for Reid Gardner, which show only m i nor i m provem e nts in visibility at th e five Class I areas with 300 km of the facility. However, the NV Energy m odeled em ission rates different from
those identif ied as BART by NDEP, as s hown in Table 5-8 of the RH SI P.

As a result of this comment errors w e re disc overed 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 whic h m i srepresent the post-B A RT annual em issions.
Note that th e NDEP post-BART em ission lim its di d not agree between T a bl es 5-6 and 5-8. The
corrected values are based on the NDEP base line em issions, NDEP baseline heat input and

NDEP BART em ission lim its. Text in section 5.5 “Summ a ry of BART Control Analyses,” section 5.6 “Visibility Improvem e nt Due to BART I m ple m entation,” section 7.2 “B ART Controls” and section 7.9.1.1 “Major and Minor S t ationary 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 a nnual em issions of NO

x are approxim a tely 57 percent of those modeled, SO 2 is 43 percent of those m o deled, and P M 10 is 57 percent of those m odeled. The total annual post-BART e m is sions ar e 50 percent of those
modeled for Reid Gardner. It is generally recognized that ther e is a linear relationship between
modeled emission rates and m odeled concentr ations when using the CALPUFF modeling
system . Therefore, it is reasonable to expect that the m odeled visibility im provem e nt is proportionally greater with the lower NDEP BART em ission lim its than the results using the higher NV Energy m odeled lim its. NDEP expects si gnificantly greater visibility im provem e nt than those presented in Table 5-11 of this SIP. In addition, it is not expected that Reid Gardner will operate at BART e m ission lim its 24 hours per day 365 days per year. All hours of Reid Gardner operation at SO 2 em issions rates less than 0.15 lb /M MBtu will resu lt in additional
im prove m e nts to the m o deled visibility.

In summ ary, the installation of BART controls at Re id Gardner will result in significant visibility
im prove m e nt at the Grand Canyon and the four other Class I areas within 300 km of t h e facility. In addition, the total annual post-BART e m issions from Tracy and Fort Churchill are 50 to 53

percen t of those m odeled by NV Energy. NDEP e xpects s i gnif i cantly greater vis i bility
im prove m e nt due to the installation of BART than that presented in Tables 5-9 and 5-10 of the SIP. No other changes were m a de to th e SIP as a result of th is comm ent.

NGO Comment 3, 6 th 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 consid er more stringent BART emission levels that further reduce or eliminate visibility impairment caused by these sources and even
consider em ission reductions that are “bey ond BART” as ha ve other states where BART has

D-143proven to be ineffective a t provid ing the emission reductions n eeded to ach i eve “reaso nable further progress” toward th e national visibility goal.

NDEP Response:
Nevada deem s our progress toward the national visi bility goal reasonable, both for the Jarbidge

W ilderness Area and for Class I areas in adjacent states. BART is one of the com ponents of Nevada’s long-term strategy to m eet the nationa l visibility goals. Section 7.9.3.2, “Contributions

to Im pairm e nt at Class I Areas Outside of Neva da,” of Nevada’s RH SIP describes Nevada’s
evaluation o f whether th e SIP includ es m easur es necessary to obtain Nevada’s share of

em issions reductions n e eded to m eet the progress goa ls in adjacent s t ates. None of the adjacen t states have contacted Nevada through the c onsultation process with requests for further

em issions reductions fro m Nevada sources as p a rt of m easures necess a ry to m eet their reasonable progress goals. Since the 2018 reason able progress goal for Jarbidge W ilderness
Area exceed s the 2018 u n iform rate of progress and other states have no t requested Nevada’s
assis t ance in m eeting their reasonab l e progres s g o als, it is not reasonable to require Nevada
sources to consider em issions reductions beyond BART.

As noted earlier in our response to N GO Comme nt 2, 1 st bullet, Southern California E d ison has
announced that the Moh a ve Generating Stati on w ill b e decomm issioned and the generating facility will be rem oved from th e site. Therefore, Mohave will no longer impact visib i lity at any
Class I area.

Finally, it is clea r f r om this comm ent and the sup porting text in section 4. 3 of the Tech Review, that Mr. Gebhart has confused the regional visibility m odeling conducted by the WRAP’s Regional Modeling Center with the post-BART di spersion modeling for estim a ting the degree of visibility im provem e nt from BA RT contro l ins t a lla tion cond ucted by th e f acilities. E P A guidance and regulation do not requ ire subje c t-to -BART f acilities to insta l l em ission-r e ducing

contro l tech nologies tha t m eet specif i c vis i bility criter ia.

The CAA requires s t a t es to consid er the f o llowin g f i ve item s in iden tif yin g BART controls : 1) costs of compliance, 2) energy and non-air qual ity environm ental im pacts of com p liance, 3) existing pollution control technology in use at th e source, 4) the rem a ining useful life of the source, and 5) the degree of visibility im prove me nt which may reasonably be anticipated from
the use of BART. There is no “cause or contri bute” threshold for the pos t-BART modeling. In addition, see NDEP’s response to the NGO co mment above regarding the de gree of visibility
im prove m e nt resulting from the insta llation of BART at Reid Gardner.

No changes were m a de to the SIP in response to this comm ent.

NGO Comment 4: 4. The RH SIP does not adequately address and miti gate Nevada’s contr i bution to vis i bility impairment at Class I areas outsi de of Nevada, in particular Nati onal Parks in the southwestern United States that are presently known to be adversely impacted by N evada emissions (i.e., Zion, Bryce Canyon, and Grand Canyon National Pa rks)

.

D-144NDEP Response: Please see the response to the pr eceding NGO co mment, which identi fies the text in Nevada’s
RH SIP that describes NDEP’s assessm e nt of the contribution of Nevada em issions to visibility
im pair m e nt at Class I areas in ad jacent 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 ni tr ate extin ction contr i bution s to Class I a r eas outside the s t ate. Fo r the worst vis i bility d a ys, Nevada’s con t ribution to su lfate extinction is 2.8 percent at the Grand Canyon, 4.8 percent at Bryc e Canyon and 5.6 percent at Zion. F o r nitrate extinction, Nevada’s contribu tion is 2.8 percent at the Gr and Canyon, 8.8 percent at B r yce Canyon and 7.9 percent at Zion.

These contribution results are based on the projec ted base18b em ission inventory, as described in
section 1.3.2.2 of Nevada’s RH SIP. The base 18b inventory does not include any em issions reductions resulting from the installation of BART at f acilities in Nevad a or the rest of the WRAP region. However, the base18b inventory does include em issions from a projected 2018 Future Coal EGU (A), which rep r ese n ts the W h ite Pine Energy Project in this inventory, and Mohave Generating Station, as di scussed above under Comment 2, 1 st bullet. Em issio n s reductions due to the installation of BART at Re id Gardner (reduction of nearly 5,500 tpy NOx

to 2018 em issions inv e n t ory), the dis m antling of the Mohave Generating Station (elim ination of nearly 19,500 tpy NOx and 8,700 tpy SO 2 from 2018 inventory), and indef i nite postponem ent of

perm itting/construction of the W h ite Pine Ener g y Project (elim i nation of 1,675 tpy NOx and 1,675 tpy SO2 from 2018 inventory), all located along the eastern boundary of Nevada, suggest
that v i sib ility im pacts due to em issio n s f r om Nevada will b e r e duced at Class I a r eas 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 sulf ate (top im age) and nitr ate (bottom i m age) 2002 baseline (plan02c em issions inventory) and 2018 projected (base18b em issions inventory) source apportionm e n t m odeling results for Grand Canyon, Zion, and Bryce Canyon, respectively.

Figure 1. S ource Apportionm ent Results for Grand Canyon.

D-145Figure 2. S ource Apportionm ent Results for Zion.

Figure 3. S ource Apportionm ent Results for Bryce Canyon.

D-146Figures 1, 2 and 3 show the relative contributions to visibility impai rm ent as paired b a rs for each state or source area, the f i rst for the baseline and the second for 2018. These figures also show
the relative reduction in contribution by each sou r ce area fro m the baseline to 2018.

Although the Grand Canyon, Zion and Bryce Canyon are not m e eting the uniform rate of progress for 2018, it is in for m ative to exam ine each sp ecies contribu tion to visibility impairm ent. Figures 4, 5 and 6 show the contr i butions to vis i bility im pairment by the in dividua l m o deled species to th ese Class I areas. Of particu l ar interest are amm o nia nitr ate and ammonia sulfate extinction, since these species are predom inantly due to em issions fr om anthropogenic sources.

These figures show that modeling results for thes e three Class I areas fail to m e et the u n iform rate of progress glide slope fo r nitrate and sulfate, except n itrate at Grand Canyon. 2018 sulfate consistently falls approxim ately 0.5 Mm -1 (0.44 to 0.48 Mm -1 ) short of the URP glide slope for
all three areas. Nitrate f a lls short 0.20 and 0.79 Mm -1 at Bryce Canyon and Zion, respectively. However, 2018 nitrate p r ogress at G r and Canyon exceeds th e URP glide slope.

Figure 4. S p eciated Contributions to Visibility Impairm e nt at Grand Canyon.

D-147Figure 5. S p eciated Contributions to Visibility Impairm e nt at Zion.

Figure 6. S p eciated Contribu tions to Visibility Impair m e nt at Bryce Canyon.

As per 40 CFR 51.308(d)(1), each state is respon sible for establishing goals that provide for reasonable progress toward achieving natural vi sibility conditions for the m a ndatory Class I
areas within the state. N one of the adjacen t states have contacted Nevada with reques t s for
further em issions reductions from Ne vada sources as part of m easures necessary to meet th eir reasonable progress goals. NDEP de em s Nevada’s progress toward the national visibility goal reasonable, both for the Jarbidge W ildernes s Area and for Class I areas in adjacen t states.

No changes were m a de to the RH SIP as a result of this comm ent.

NGO Comment 4, continued: Regional modeling using the 2018 WRAP inventory pr ojections show that visibility at Grand Canyon, Zion, and Bryce Canyon National Parks will not a c hieve the Uniform Rate of Progress (URP) goals and that the “glide path” for visibili ty improvem ent to natural conditions by 2064
will not b e a c hieved with out addition al emissi on reductions. This find i ng occurs even without considering that future grow th from Nevada coal-fired E GUs appears to be significantly underrepresented in the 2018 inventory. As source emissions from within Nevada are shown to
“cause and contribute” to visibilit y impairment at Class I areas outside of the state, N evada needs to revisit its draft regional haze SIP and craft an emissions reduction plan that helps

D-148achieve the URP goals at Class I areas outside o f

Nevada. Achievi ng the national visibility goal and meeting the 2018 URP mileston es will r e quire aggress i ve action s fro m all states in the region, including Nevada. Nevada has established BART emission limits in th e draft SIP that fail to provide meaningful im provement in visibility conditions and that con tinue to show Nevada’s
emissions sources will “ c ause and contribute” to visibility impairment. These findings
demonstrate that Nevada ’s draft regional haze SIP as written fails to meet its pr imary objective of provid ing the in itia l step toward meeting the n a tional vis i b ility goal.

NDEP Response:
This comm e n t incorporates several of the previous NGO co mm ents. NDEP has addressed comments regarding the under-representation of Nevada’s em ission inventory, Nevada’s visibility im pacts at Clas s I areas in adjacen t st ates, and Nevada’s BART determ inatio ns in our responses above. Again it appear s that the NGOs are not well ve rsed on the differences between the BART guidance and the RHR. Cause and co ntri bu te is o n ly a cr ite ria to dete rm ine whether a BART-eligible source will b e subject to a full BART determ ination. Fin a lly, Nevada deem s our progress reasonable for all Class I areas, both those in adjacent st ates, as well as the J a rbidge

W ilderness Area, as stated previously. Neva da projected 2018 reductions of anthropogenic

em issions are proportional to our contri butions to visibility im pairm e nt.

No changes were m a de to the RH SIP as a result of this comm ent.

NGO Comment 5: 5. There is an inadequate explanation in th e RH SIP regarding why the mining and mine processing sites were not included in the RH SIP inventory. P l ease either include th ese 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 indust r ial em issions inside and o u t side of Nevada were also considered when evaluating vis i bility conditions at Jarbidge. Within Nevada, major emission sources that could affect Jarbidge inclu d e the Valm y Station, a co al-fired EGU, along with m a jor gold
mines and other m i neral operations in t h e state. All of these e m is sions appear to be
included in the WRAP e m issions inv e ntory relied upon by ND EP for the re gional haz e SIP .” Em phasis added b y NDEP.

Since the referenced em i ssion sources are in clude d in the RH SIP inventory as stated in Mr.
Gebhart’s T ech Review, this comm ent is spu r iou s and no changes were made to the SIP based on
this comm ent.

D-149