SOUTH COAST AIR QUALITY MANAGEMENT DISTRICTFinal –Methodology to Cal!late "a#ti!late Matte# $"M% &'( and "M &'( Signi)iane Th#e*hold* Oto+e# &,,- E.e!ti/e O))ie# Barry R. Wallerstein, D. Env. De0!ty E.e!ti/e O))ie# "lanning1 R!le De/elo02ent and A#ea So!#e* Elaine Chang, DrPH A**i*tant De0!ty E.e!ti/e O))ie# "lanning1 R!le De/elo02ent and A#ea So!#e* Laki Tisopulos, Ph.D., P.E. "lanning and R!le* Manage# "lanning1 R!le De/elo02ent and A#ea So!#e* Susan Nakaura A!tho#*3 !ike "rause #ir $uality Spe%ialist Steve Sith, Ph.D. Progra Supervisor Tehnial A**i*tane& 'aes "oi(ui #ir $uality Spe%ialist To Chi%o Progra Supervisor Ro)ert Wu #ir $uality Spe%ialist *in+iu ,hang #ir $uality Spe%ialist 'oe Cassassi Planning !anager 'ulia Lester, Ph.D. SOUTH COAST AIR QUALITY MANAGEMENT DISTRICT GO4ERNING 5OARD CH#-R!#N& W-LL-#! #. B.R"E, E/.D. Speaker o0 the #sse)ly #ppointee 1-CE CH#-R!#N& S. R23 W-LS2N, E/.D. Supervisor, 4ourth Distri%t Riversi/e County Representative !E!BERS& !-CH#EL D. #NT2N21-CH Supervisor, 4i0th Distri%t Los #ngeles County Representative '#NE W. C#RNE3 Senate Rules Coittee #ppointee R2N#LD 2. L21ER-D5E !ayor, City o0 Riversi/e Cities Representative, Riversi/e County 5#R3 21-TT Supervisor, 4ourth Distri%t San Bernar/ino County Representative '#N PERR3 Coun%ile)er, Ninth Distri%t, City o0 Los #ngeles Cities Representative, Los #ngeles County, Western Region !-5.EL #. P.L-D2 !ayor, City o0 Santa #na Cities Representative, 2range County T2N-# RE3ES .R#N5# Coun%ile)er, Seventh Distri%t, City o0 Long Bea%h Cities Representative, Los #ngeles County, Eastern Region '#!ES S-L1# Supervisor, Se%on/ Distri%t 2range County Representative C3NTH-# 1ERD.526PER#LT# 5overnor7s #ppointee DENN-S 3#TES !ayor, City o0 Chino Cities Representative, San Bernar/ino County E*EC.T-1E 244-CER& B#RR3 R. W#LLERSTE-N, D.Env. TA5LE OF CONTENTS CH#PTER 8 6 PR2'ECT DESCR-PT-2N -ntro/u%tion............................................................................................. 8 Ba%kgroun/............................................................................................. 8 !etho/ology to Cal%ulate P!9.:........................................................... 9 Lo%ali(e/ Signi0i%an%e Threshol/ 0or P!9.: Eissions....................... ; Regional Eissions Threshol/ o0 Signi0i%an%e 0or P!9.:................................................................................................ < Con%lusion.............................................................................................. = Ta)les Ta)le 8 4e/eral Stan/ar/s 0or Parti%ulate !atter................................... 8 Ta)le 9 Cali0ornia Stan/ar/s 0or Parti%ulate !atter............................... 9 Ta)le > Total Stationary Sour%e 4uel Co)ustion -nventory ?Tons@DayA............................................................................. B Ta)le ; Total 4ugitive P! -nventory ?Tons@DayA.................................. B Ta)le : Co)ustion P! -nventory 0ro 2006Roa/ E+uipent ?Tons@DayA........................................................................... < Ta)le B Regional #ir $uality Signi0i%an%e Threshol/s.......................... < #PPEND-* # 6 .PD#TED CE-D#RS T#BLE L-ST W-TH P!9.: 4R#CT-2NS #PPEND-* B C P!9.: L2C#L-,ED S-5N-4-C#NCE THRESH2LD L22"6.P T#BLES i 2%to)er 9DDB 4inal P!9.: Cal%ulation !etho/ology an/ P!9.: Signi0i%an%e Threshol/s Int#od!tion -n the last 0eE years, )oth Cali0ornia an/ the 0e/eral governents have esta)lishe/ a)ient air +uality stan/ar/s 0or 0ine parti%ulate atter ?P!A less than or e+ual to 9.: i%rons in /iaeter ?P!9.:A. #s a result, there is a nee/ to esta)lish a etho/ology 0or %al%ulating P!9.: an/ appropriate P!9.: signi0i%an%e threshol/s 0or the purpose o0 analy(ing lo%al an/ regional P!9.: air +uality ipa%ts in Cali0ornia Environental $uality #%t ?CE$#A an/ National Environental Poli%y #%t ?NEP#A air +uality analyses. This /o%uent provi/es a etho/ology 0or %al%ulating P!9.: an/ re%oen/ations 0or lo%ali(e/ an/ regional P!9.: signi0i%an%e threshol/s. 5a6g#o!nd P! larger than 9.: i%rons an/ less than 8D i%rons, o0ten re0erre/ to as the %oarse P! 0ra%tion ?or P!8DA, is ostly pro/u%e/ )y e%hani%al pro%esses. These in%lu/e autoo)ile tire Eear, in/ustrial pro%esses su%h as %utting an/ grin/ing, an/ re6suspension o0 parti%les 0ro the groun/ or roa/ sur0a%es )y Ein/ an/ huan a%tivities su%h as %onstru%tion or agri%ulture. -n %ontrast, P! less than or e+ual to P!9.: is ostly /erive/ 0ro %o)ustion sour%es, su%h as autoo)iles, tru%ks, an/ other vehi%le eFhaust, as Eell as 0ro stationary %o)ustion sour%es. The parti%les are either /ire%tly eitte/ or are 0ore/ in the atosphere 0ro the %o)ustion o0 gases, su%h as N2F an/ S2F %o)ining Eith aonia. P!9.: %oponents 0ro aterial in the earthGs %rust, su%h as /ust, are also present, Eith the aount varying in /i00erent lo%ations. Sta00Gs re%oen/ation 0or %al%ulating P!9.: 0o%uses only on /ire%tly eitte/ P!9.:. -n 8HH<, ..S. EP# esta)lishe/ an annual an/ a 9;6hour stan/ar/ 0or the 0inest 0ra%tion o0 parti%ulates, P!9.:, to %opleent the eFisting P!8D stan/ar/s. HoEever, ..S. EP# re%ently o/i0ie/ the 9;6hr P!9.: stan/ar/ an/ revoke/ the annual P!8D stan/ar/. ?Ta)le 8A. The annual %oponent o0 the stan/ar/ Eas esta)lishe/ to provi/e prote%tion against typi%al /ay6to6/ay eFposures as Eell as longer6ter eFposures, Ehile the /aily %oponent prote%ts against ore eFtree short6ter events. TA5LE 7 4e/eral Stan/ar/s 0or Parti%ulate !atter Fede#al Standa#d* "M 7, "M &'( #nnual Revoke/ 8 8: Ig@ > 9;6Hour 8:D Ig@ > >: Ig@ > 9 -n 'une 9DD9, the Cali0ornia #ir Resour%es Boar/ ?C#RBA a/opte/ neE, stri%ter stan/ar/s 0or parti%ulate atter that Eoul/ a00e%t )oth the %oarse as Eell as 0ine parti%ulate 0ra%tion ?Ta)le 9A. C#RB /elaye/ a%tion on the propose/ 9;6hour P!9.: stan/ar/ in light o0 the 8 ..S. EP# 0inal ruleaking 0or C4R ;D Part :D.< National Priary an/ Se%on/ary #)ient #ir $uality Stan/ar/s at http&@@epa.gov@p@p/
[email protected]/0 9 ..S. EP# 0inal ruleaking 0or C4R ;D Part :D.8> National Priary an/ Se%on/ary #)ient #ir $uality Stan/ar/s at http&@@epa.gov@p@p/
[email protected]/0 8 2%to)er 9DDB 4inal P!9.: Cal%ulation !etho/ology an/ P!9.: Signi0i%an%e Threshol/s 0in/ings relate/ to statisti%al issues in several key short6ter eFposure health e00e%ts stu/ies. TA5LE & Cali0ornia Stan/ar/s 0or Parti%ulate !atter Cali)o#nia Standa#d* "M 7, "M &'( #nnual 9D Ig@ > 89 Ig@ > 9;6Hour :D Ig@ > n@a Methodology to Cal!late "M &'( Be%ause there are %urrently 0eE or no P!9.: eission 0a%tors 0or e%hani%al or %o)ustion pro%esses, sta00 is re%oen/ing an in/ire%t approa%h to %al%ulating P!9.: eissions until su%h tie as P!9.: 0a%tors are /evelope/. Sin%e P!9.: is a su)set o0 P!8D, the %urrent etho/ology 0or %al%ulating P!8D 0ro 0ugitive /ust sour%es ?gra/ing, /eolition, unpave/ roa/s, open storage piles, et%.A an/ %o)ustion sour%es ?stationary %o)ustion sour%es, vehi%le eFhaustA Eill %ontinue to )e use/ to %al%ulate P!8D an/ %an also )e use/ to %al%ulate P!9.:. Total suspen/e/ P! ?TSPA eissions typi%ally %ontain spe%i0i% 0ra%tions o0 P!8D an/ P!9.: that %an )e easure/. -n general, P! 0ro 0ugitive /ust generating sour%es is priarily %opose/ o0 P!8D Eith a relatively sall 0ra%tion o0 the 0ugitive P! %onsisting o0 P!9.:. #lternatively, P! 0ro %o)ustion sour%es is priarily %opose/ o0 P!9.: Eith a sall 0ra%tion %onsisting o0 P!8D. To %al%ulate )oth P!8D an/ P!9.:, eFisting P!8D %al%ulation etho/ologies 0or )oth 0ugitive /ust P!8D an/ %o)ustion P!8D %an )e use/. To /eterine the P!9.: 0ra%tions o0 the P!8D eission results, sta00 is re%oen/ing that the P!8D eissions )e %al%ulate/ using stan/ar/ P!8D %al%ulation etho/ologies. The P!8D eission results 0or ea%h eission sour%e or operation Eoul/ then )e ultiplie/ )y the appli%a)le P!9.: 0ra%tion, /erive/ )y eissions sour%e, using P! pro0iles in the Cali0ornia Eission -nventory Data an/ Reporting Syste ?CE-D#RSA /evelope/ )y the Cali0ornia #ir Resour%es Boar/ ?C#RBA. The CE-D#RS P! pro0iles are use/ to /evelop eission inventories 0or a variety o0 sour%es an/ operations in the #ir $uality !anageent Plan ?#$!PA. The CE-D#RS P! pro0iles have )een strealine/ to )e use/ 0or ost types o0 pro%esses that Eoul/ )e en%ountere/ in a CE$# or NEP# /o%uent -n a//ition, #$!D sta00 has i/enti0ie/ the P!9.: 0ra%tion o0 P!8D. The strealine/ CE-D#RS P! pro0iles %an )e 0oun/ in #ppen/iF #. The CE-D#RS P! pro0iles ay )e up/ate/ as ne%essary to re0le%t up/ates prepare/ )y C#RB. -0 the proKe%t )eing evaluate/ is not liste/ aong the %ategories in #ppen/iF #, then the %losest relate/ type o0 operation@pro%ess shoul/ )e use/. 4or eFaple in analy(ing %onstru%tion a%tivities, e.g., gra/ing, earth oving, et%., i0 the spe%i0i% a%tivity is not lo%ate/ in the ta)les the CE$# pra%titioner %an use the 0olloEing /e0ault 0a%tors /erive/ 0ro the 9DD> #$!P annual inventories ?see Ta)les > an/ ; )eloE un/er the LLo%ali(e/ Signi0i%an%e Threshol/s 0or P!9.: EissionsM /is%ussionA. 4or e%hani%al /ust generating sour%es, e.g., %onstru%tion, the P!9.: 0ra%tion o0 P!8D is 98 per%ent an/ 0or %o)ustion sour%es the P!9.: 0ra%tion o0 P!8D is HH per%ent. 4or o006roa/ %o)ustions 9 2%to)er 9DDB 4inal P!9.: Cal%ulation !etho/ology an/ P!9.: Signi0i%an%e Threshol/s sour%es, the P!9.: 0ra%tion /e0ault Eoul/ )e =H per%ent ?Ta)le :A. 2ther pu)li%ly availa)le an/ peer revieEe/ sour%es o0 P!8D an/ P!9.: eission 0a%tors %an also )e use/ i0 they ore %losely at%h the type o0 eission sour%e than the sour%es i/enti0ie/ in #ppen/iF #. -n a//ition, site6spe%i0i% or proKe%t6spe%i0i% in0oration %an )e use/. 2n%e the P!8D 0ra%tions 0ro all eissions sour%es are %al%ulate/, these are sue/ an/ %opare/ to the appropriate P!8D signi0i%an%e threshol/s to /eterine Ehether or not a proKe%t is signi0i%ant. Siilarly, on%e the P!9.: 0ra%tions 0ro all eissions sour%es have )een %al%ulate/, these are also sue/ ?separate 0ro the P!8D 0ra%tionsA an/ %opare/ to the appropriate P!9.: signi0i%an%e threshol/ ?see 0olloEing /is%ussionA to /eterine proKe%t signi0i%an%e. The P!9.: 0ra%tion o0 P!8D %an )e easily %al%ulate/ as 0olloEs. Step 8& Cal%ulate P!8D eissions 0or ea%h eissions sour%e %ategory. Step 9& Look up the P!9.: 0ra%tion o0 P!8D 0or the appli%a)le sour%e %ategory )y year that %onstru%tion Eill o%%ur or operation o0 the proKe%t Eill )egin ?#ppen/iF #, %olun B o0 the appropriate ta)leA. Step >& !ultiply the P!9.: 0ra%tion )y the P!8D eissions 0or ea%h sour%e %ategory ?P!9.: eissions N P!8D eissions F OP!9.: 0ra%tionPA Step ;& Su the P!9.: eissions 0ro ea%h eissions sour%e. Step :& Copare P!9.: eissions to the appropriate signi0i%an%e threshol/. EFaple& # proKe%t is estiate/ to generate = poun/s per /ay o0 P!8D 0ro one pie%e o0 %onstru%tion e+uipent. The P!9.: eissions are as 0olloEs& P!9.: eissions N = poun/s o0 P!8D per /ay F D.=H N <.89 poun/s o0 P!9.: per /ay. -n %onKun%tion Eith esta)lishing a etho/ology 0or %al%ulating P!9.:, sta00 has /evelope/ the 0olloEing re%oen/e/ P!9.: signi0i%an%e threshol/s 0or )oth lo%ali(e/ an/ regional signi0i%an%e 0or )oth %onstru%tion an/ operation. Loali8ed Signi)iane Th#e*hold* )o# "M &'( E2i**ion* Lo%ali(e/ signi0i%an%e threshol/s ?LSTsA Eere /evelope/ in response to the SC#$!D 5overning Boar/Gs environental Kusti%e ?E'A initiatives ?E' initiative -6;A in re%ognition o0 the 0a%t that %riteria pollutants, %ar)on onoFi/e ?C2A, oFi/es o0 nitrogen ?N2FA, an/ P!8D in parti%ular, %an have lo%al ipa%ts as Eell as regional ipa%ts. The LST proposal Eent through eFtensive pu)li% outrea%h an/ Eas a/opte/ )y the 5overning Boar/ in 2%to)er 9DD>. #t the tie the LST Eas a/opte/ )y the 5overning Boar/, sta00 ha/ not yet /evelope/ propose/ LSTs 0or P!9.:. > 2%to)er 9DDB 4inal P!9.: Cal%ulation !etho/ology an/ P!9.: Signi0i%an%e Threshol/s Deterining lo%ali(e/ air +uality ipa%ts re+uires /ispersion o/eling. Be%ause lo%al lea/ agen%ies ay not have the eFpertise or resour%es to per0or /ispersion o/eling, SC#$!D %reate/ a series o0 look6up ta)les 0or C2, N2F, an/ P!8D in Ehi%h sta00 )a%k6 %al%ulate/ the ass eissions ne%essary to e+ual or eF%ee/ the %onstru%tion or operation LST. The look6up ta)les Eere %reate/ 0or proKe%ts one to 0ive a%res in si(e an/ take into %onsi/eration lo%ation ?sour%e re%eptor areaA an/ /istan%e to the sensitive re%eptor. To use the look6up ta)les, the lea/ agen%y %al%ulates /aily eission as it norally Eoul/ an/ then %opares the results to the eissions in the appli%a)le look6up ta)le. -n general, the LSTs Eill apply priarily to %onstru%tion )e%ause eissions 0ro %onstru%tion e+uipent o%%ur at a 0iFe/ lo%ation %opare/ to operation, Ehi%h, 0or ost lan/ use proKe%ts, %onsists o0 eissions 0ro vehi%les traveling over the roa/Eays, Ehi%h, there0ore, /o not %reate ipa%ts to a single lo%ation. To 0urther assist lea/ agen%ies Eith %al%ulating %onstru%tion eissions, the SC#$!D %on/u%te/ %onstru%tion site surveys 0or ea%h phase o0 %onstru%tion to /evelop stan/ar/ %onstru%tion s%enarios relative to %onstru%tion e+uipent an/ hours o0 operation. Sprea/sheets Eere /evelope/ to %al%ulate eissions 0or the %onstru%tion s%enarios in an e00ort to %reate s%enarios that Eoul/ not eF%ee/ any appli%a)le LSTs. When preparing a CE$# analysis, lea/ agen%ies %oul/ use the saple %onstru%tion proKe%ts 0or their %onstru%tion analyses, use the sprea/sheets to tailor the analysis to their in/ivi/ual proKe%ts, or use a %o)ination o0 the tEo. The 0olloEing su)se%tions /es%ri)e the propose/ P!9.: LSTs 0or )oth operation an/ %onstru%tion. E*ta+li*hing LST* To /eterine the e00e%ts o0 P!9.: on lo%al ?near)yA re%eptors, su%h as resi/ents, hospitals, s%hools, et%., a P!9.: lo%ali(e/ signi0i%an%e threshol/ ?LSTA nee/s to )e esta)lishe/. Sin%e the Basin eF%ee/s one or ore o0 the state or 0e/eral a)ient air +uality stan/ar/s 0or P!9.:, the pro%ess use/ to /eterine signi0i%an%e 0or attainent pollutants, i.e., N29 an/ C2, /evelope/ 0or the LST progra %annot )e use/ > . .n/er the LST progra, sin%e P!8D is a nonattainent pollutant, the LST etho/ology uses a /i00erent pro%ess 0or /eterining Ehether lo%ali(e/ P!8D air +uality ipa%ts are signi0i%ant. To /eterine lo%ali(e/ P!8D air +uality ipa%ts /uring operation, the LST etho/ology uses as a signi0i%an%e threshol/ the alloEa)le %hange in %on%entration threshol/ 0or P!8D liste/ in Rule 8>D>, Ta)le #69, Ehi%h is 9.: i%rogras per %u)i% eter ?Ig@ > A. The alloEa)le %hange in %on%entration threshol/ is a o/ele/ %on%entration that %annot )e eF%ee/e/ at the sensitive re%eptor, an/ /eterines Ehether or not a perit appli%ant Eill re%eive a perit 0ro the SC#$!D. 4or the LST progra sta00 use/ a /ispersion o/el ?-SCST>A to %onvert the 9.: Ig@ > %on%entration into ass /aily P!8D eissions nu)ers )ase/ on the si(e o0 the proKe%t, lo%ation o0 the proKe%t, an/ /istan%e to the sensitive re%eptor. The > .n/er the LST progra, to /eterine signi0i%an%e 0or attainent pollutants, the eissions %ontri)ution 0ro the proKe%t eFpresse/ as a %on%entration is a//e/ to the highest lo%al a)ient %on%entration 0ro the last three years Ehere /ata are availa)le. -0 the su is e+ual to or greater than any appli%a)le state or 0e/eral a)ient air +uality stan/ar/, the proKe%t is %onsi/ere/ to have signi0i%ant lo%ali(e/ air +uality ipa%ts 0or that pollutant. !ore in0oration on the LST progra %an )e 0oun/ at the 0olloEing .RL& http&@@EEE.a+/.gov@%e+a@han/)ook@
[email protected]. ; 2%to)er 9DDB 4inal P!9.: Cal%ulation !etho/ology an/ P!9.: Signi0i%an%e Threshol/s results Eere then in%orporate/ into an LST look6up ta)le. -0 the ass eissions 0ro a proKe%t eF%ee/ the appli%a)le LST look6up ta)lesG ass eission nu)ers ?Ehi%h are )ase/ on the 9.: Ig@ > %on%entrationA, then lo%ali(e/ P!8D air +uality ipa%ts are %onsi/ere/ to )e signi0i%ant. Operational Localized Significance Thresholds To esta)lish operational P!9.: lo%ali(e/ signi0i%an%e threshol/s, sta00 0irst revieEe/ the P! inventories in #ppen/iF --- o0 the 9DD> #$!P. -n parti%ular, sta00 evaluate/ the %oposition o0 P!8D an/ P!9.: 0ro %o)ustion pro%esses in the 9DD> #$!P to esta)lish a general ratio o0 P!9.: to P!8D. Co)ustion pro%esses Eere evaluate/ )e%ause, 0or ost lan/ use proKe%ts, o)ile sour%e %o)ustion eissions %oprise the aKority o0 eissions. Ta)le > shoEs the total P!8D an/ P!9.: inventories 0or total 0uel %o)ustion pro%ess 0or the years 9DD: through 9D8D. #s %an )e seen in Ta)le >, over the 0ive6year tie0rae %onsi/ere/, the 0ra%tion o0 %o)ustion P!8D that %onsists o0 P!9.: is %onsistently HH per%ent. Sin%e %o)ustion P!8D an/ P!9.: 0ra%tions are essentially e+uivalent, sta00 is re%oen/ing that the operational lo%ali(e/ signi0i%an%e threshol/ 0or P!9.: )e the sae as the %urrent operational lo%ali(e/ signi0i%an%e threshol/ 0or P!8D, i.e., 9.: Ig@ > . TA5LE 9 Total Stationary Sour%e 4uel Co)ustion -nventory ?Tons@DayA Yea# "M 7, "M &'( "e#ent o) "M 7, :hih i* "M &'( 9DD: =.8> =.D8 HH 9DDB =.98 =.8D HH 9DD< =.>D =.8= HH 9DD= =.>= =.9B HH 9D8D =.:; =.;9 HH Sour%e& #ppen/iF ---, 9DD> #$!P, #nnual #verage Eission -nventory Construction Localized Significance Thresholds Siilarly, to /evelop a P!9.: %onstru%tion signi0i%an%e threshol/ 0or lo%ali(e/ ipa%ts, sta00 %onsi/ere/ the P!9.: %ontri)ution 0ro 0ugitive sour%es an/ the P!9.: %ontri)ution 0ro %o)ustion sour%es ?%onstru%tion e+uipentA. #s /is%usse/ in ore /etail in the 0olloEing paragraphs, %o)ustion eissions 0ro the %onstru%tion e+uipent %ontri)ute a larger portion o0 the total P!9.: eissions 0ro %onstru%tion operations than 0ugitive sour%es. Sta00 then revieEe/ the 9DD> #$!P, #ppen/iF --- 0ugitive P! inventory 0or %onstru%tion an/ /eolition to o)tain the P!8D an/ P!9.: %opositions. Ta)le ; shoEs the total P!8D an/ P!9.: inventories 0or %onstru%tion a%tivities 0or the years 9DD: through 9D8D. #s %an )e seen in Ta)le ;, over the 0ive6year tie0rae, the 0ra%tion o0 P!8D that %onsists o0 P!9.: is %onsistently 98 per%ent. !ultiplying the 0ugitive P!9.: per%ent 0ra%tion o0 : 2%to)er 9DDB 4inal P!9.: Cal%ulation !etho/ology an/ P!9.: Signi0i%an%e Threshol/s P!8D )y the eFisting %onstru%tion P!8D LST, 8D.; Ig@ > , pro/u%es a result o0 approFiately 9.9 Ig@ > . TA5LE ; Total 4ugitive P! -nventory ?Tons@DayA Yea# "M 7, "M &'( "e#ent o) "M 7, :hih i* "M &'( 9DD: ;9.< =.H8 98 9DDB ;>.BB H.88 98 9DD< ;;.B H.> 98 9DD= ;:.:; H.: 98 9D8D ;<.;; H.H 98 Sour%e& #ppen/iF ---, 9DD> #$!P, #nnual #verage Eission -nventory 2006roa/ %onstru%tion e+uipent, hoEever, also %ontri)utes %o)ustion P! as Eell as 0ugitive P!. To /eterine the %ontri)ution o0 P!9.: 0ro %onstru%tion e+uipent %o)ustion eissions, sta00 per0ore/ /ispersion o/eling using the -SCST> /ispersion o/el 0or one6, tEo6, an/ 0ive6a%re %onstru%tion s%enarios. The %onstru%tion s%enarios Eere /evelope/ 0ro %onstru%tion site surveys %on/u%te/ in %onne%tion Eith sta00Gs original LST proposal. Co)ustion sour%es Eere o/ele/ as a/Ka%ent 0ive6eter volue sour%es an/ 0ugitive sour%es Eere o/ele/ as a/Ka%ent one6eter area sour%es. Worst6%ase eteorologi%al /ata 0ro the West Los #ngeles sour%e re%eptor area Eere use/ an/ re%eptors Eere pla%e/ at 9:, :D, 8DD, 9DD, an/ :DD eter /istan%es 0ro the %onstru%tion site. .sing C#RB spe%iation /ata, it Eas assue/ that 98 per%ent o0 0ugitive /ust P!8D is %oprise/ o0 P!9.: an/ =H per%ent o0 o006roa/ e+uipent %o)ustion P!8D eissions are %oprise/ o0 P!9.: ?)ase/ 9DD> #$!P inventories, see Ta)le :A. TA5LE ( Co)ustion P! -nventory 0ro 2006Roa/ E+uipent ?Tons@DayA Yea# "M 7, "M &'( "e#ent o) "M 7, :hih i* "M &'( 9DD: 88.H: 8D.B; =H 9DDB 88.B8 8D.>> =H 9DD< 88.9 H.H< =H 9DD= 8D.H> H.<8 =H 9D8D 8D.9B H.DH =H Sour%e& #ppen/iF ---, 9DD> #$!P, #nnual #verage Eission -nventory The o/eling results shoEe/ that %o)ustion P!9.: 0ro o006roa/ e+uipent %oprise approFiately <: to 8DD per%ent o0 the total P!9.: eissions 0ro %onstru%tion a%tivities. 4urther, the P!9.: %ontri)ution 0ro 0ugitive sour%es is /epen/ant on the %onstru%tion phase. 4or eFaple, the o/eling shoEe/ that the /eolition an/ site preparation phases have the highest 0ugitive P!9.: %ontri)ution to the overall results, Ehereas, the )uil/ing an/ asphalt paving phases %ontri)ute the ost %o)ustion P!9.: to the overall results. B 2%to)er 9DDB 4inal P!9.: Cal%ulation !etho/ology an/ P!9.: Signi0i%an%e Threshol/s The o/eling results in/i%ate that the %ontri)ution o0 o006roa/ %o)ustion P!9.: eissions %an )e three to 0our ties higher than the %ontri)ution o0 P!9.: 0ro 0ugitive sour%es. Base/ on this result, sta00 re%oen/s that the P!9.: 0ugitive /ust %oponent )e a/Kuste/ upEar/ )y approFiately 0our ties to a%%ount 0or the P!9.: eissions 0ro the %onstru%tion e+uipent. #s a result, sta00 is re%oen/ing a P!9.: %onstru%tion LST o0 8D.; Ig@ > , the sae as the %onstru%tion LST 0or P!8D. 4inally, an eF%ee/an%e o0 either the P!8D %onstru%tion LST or the P!9.: %onstru%tion LST is a signi0i%ant a/verse lo%ali(e/ air +uality ipa%t. Regional E2i**ion Th#e*hold o) Signi)iane )o# "M &'( Eissions that eF%ee/ the regional signi0i%an%e threshol/s are ass /aily eissions that ay have signi0i%ant a/verse regional e00e%ts an/ are the air +uality signi0i%an%e threshol/s Eith Ehi%h ost CE$# pra%titioners are 0ailiar. Ta+le - Regional #ir $uality Signi0i%an%e Threshol/s Mass Daily Thresholds a "oll!tant Con*t#!tion + 2peration % N2F 8DD l)s@/ay :: l)s@/ay 12C <: l)s@/ay :: l)s@/ay P!8D 8:D l)s@/ay 8:D l)s@/ay S2F 8:D l)s@/ay 8:D l)s@/ay C2 ::D l)s@/ay ::D l)s@/ay Lea/ > l)s@/ay > l)s@/ay The 0olloEing su)se%tion /es%ri)es the propose/ P!9.: regional signi0i%an%e threshol/s 0or )oth operation an/ %onstru%tion. E*ta+li*hing Regional Signi)iane Th#e*hold* P! eissions also a00e%t air +uality on a regional )asis. When 0ugitive /ust enters the atosphere, the larger parti%les o0 /ust typi%ally 0all +ui%kly to the groun/, )ut saller parti%les less than 8D i%rons in /iaeter ay reain suspen/e/ 0or longer perio/s, giving the parti%les tie to travel a%ross a regional area an/ a00e%ting re%eptors at soe /istan%e 0ro the original eissions sour%e. 4ine P!9.: parti%les have even longer atospheri% resi/en%y ties. Sta00 is re%oen/ing a P!9.: regional signi0i%an%e threshol/ )ase/ on a re%ent EP# proposal, as eFplaine/ in the 0olloEing paragraphs. 2n Septe)er =, 9DD:, EP# pu)lishe/ in the 4e/eral Register LPropose/ Rule to -pleent the 4ine Parti%le National #)ient #ir $uality Stan/ar/s,M Ehi%h propose/ a signi0i%ant eission rate 0or P!9.: o0 8D tons per year. Sta00 is proposing to use EP#Gs < 2%to)er 9DDB 4inal P!9.: Cal%ulation !etho/ology an/ P!9.: Signi0i%an%e Threshol/s signi0i%ant eission rate 0or P!9.: to /evelop the /aily ass eission regional signi0i%an%e threshol/ 0or P!9.:. Converting the annual rate, 8D tons, into a /aily rate pro/u%es a /aily rate o0 approFiately :: poun/s per /ay. # siilar approa%h Eas use/ to /erive the operational regional signi0i%an%e threshol/s 0or N29 an/ 12C. N29 an/ 12C operational regional signi0i%an%e threshol/s Eere /erive/ )y using the N2F@12C eission rate that /e0ine/ a aKor sour%e in the South Coast #ir Basin, 8D tons per year. Converting the annual eissions rate into a /aily rate resulte/ in a regional operational signi0i%an%e threshol/ o0 :: poun/s per /ay 0or ea%h pollutant. Siilar to the regional signi0i%an%e threshol/ 0or P!8D o0 8:D poun/s per /ay, the propose/ P!9.: regional signi0i%an%e threshol/ o0 :: poun/s per /ay Eoul/ apply to )oth %onstru%tion an/ operation. Conl!*ion -n this /o%uent sta00 i/enti0ie/ a etho/ology to in/ire%tly %al%ulate P!9.: eissions 0or a CE$# or NEP# air +uality analysis, to )e use/ until su%h tie as P!9.: eission 0a%tors are availa)le, Ehi%h Eill alloE the CE$# pra%titioner to %al%ulate P!9.: eissions /ire%tly. -n a//ition, P!9.: %onstru%tion an/ operation LSTs have )een i/enti0ie/ to a//ress lo%ali(e/ ipa%ts. The P!9.: LSTs Eill )e use/ to /evelop look6up ta)les 0or proKe%ts 0ive a%res in si(e or saller, siilar to those prepare/ 0or P!8D, nitrogen /ioFi/e ?N29A, an/ %ar)on onoFi/e ?C2A. #s Eith the other pollutants, the P!9.: look6up ta)les %an )e use/ as a s%reening pro%e/ure to /eterine Ehether or not sall proKe%ts ?less than or e+ual to 0ive a%resA Eill generate signi0i%ant a/verse lo%ali(e/ air +uality ipa%ts. S%reening pro%e/ures are )y /esign %onservative, that is, the pre/i%te/ ipa%ts ten/ to overestiate the a%tual ipa%ts. -0 the pre/i%te/ ipa%ts are a%%epta)le using the LST look6up ta)les, then a ore /etaile/ evaluation is not ne%essary. HoEever, i0 the pre/i%te/ ipa%ts are signi0i%ant, then the proKe%t proponent ay Eish to per0or a ore /etaile/ eission an/@or o/eling analysis )e0ore %on%lu/ing that the ipa%ts are signi0i%ant. ProKe%t proponents are not re+uire/ to use this LST pro%e/ureQ an/ ay %oplete site spe%i0i% o/eling instea/. Site6spe%i0i% o/eling is re+uire/ 0or proKe%ts larger than 0ive a%res. = 2%to)er 9DDB