TSD-1c



## Emissions Processing for 2002 OTC Regional and Urba n

12km Base Year Simulation

Bureau of Air Quality Analysis and Research

Division of Air Resources New York State Department of Environmental Conserva tion

Albany, NY 12233

March 19, 20072 Overview All emissions processing for the revised 2002 OTC r egional and urban 12 km base case simulations was performed with SMOKE2.1 c ompiled on a Red Hat 9.0 Linux operating system with the Portland group fortran co mpiler version 5.1. The emissions processing was performed on a month-by-month and RP O-by-RPO basis, i.e. SMOKE processing was performed for each month for each of the RPOs (MANE-VU, VISTAS, CENRAP, MRPO) individually as well as for Canada. F or each month/RPO combination, a separate SMOKE ASSIGNS file was created, and the length of the episode in each of these ASSIGNS files was set to the entire month. Al so, as discussed in Section 3, there was no difference between “episode-average” tempera tures and “monthly-average” temperatures for the Mobile6 simulations that used the option of temperature averaging. This document is structured as follows: A listing o f all emission inventories is given in Section 2, organized by RPO and source cat egory. Section 3 discusses the Mobile6 processing approach employed for the differ ent RPOs, while Section 4 describes the processing of biogenic emissions with BEIS3.12. Finally, Sections 5 through7 describe the temporal allocation, speciation, and s patial allocation of the emissions inventories, respectively. 1. Emission Inventories

1.1 MANE-VU Version 3 of the MANE_VU inventory was utilized to generate CMAQ-ready emissions. This emissions inventory data were obtai ned from the MANEVU archive in April 2006. 1.1.1 Area Sources

• Files: MANEVU_AREA_SMOKE_INPUT_ANNUAL_SUMMERDAY_040606.txt and MANEVU_AREA_SMOKE_INPUT_ANNUAL_WINTERDAY_040606 .txt prepared by PECHAN, downloaded from ftp.marama.org (username mane-vu, password exchange) • Fugitive dust correction: This was applied as count y-specific correction factors for SCC’s listed at http://www.epa.gov/ttn/chief/emch/invent/index.html #dust ; the correction factor file gcntl.xportfrac.txt was obta ined from EPA’s CAIR NODA ftp site http://www.airmodelingftp.com (password protected).; this adjustment was performed using the SMOKE programs cntlmat and grwinven to generate an adjusted IDA inventory file used for subsequent SMO KE processing 1.1.2 Nonroad Sources

• File: MANEVU_NRD2002_SMOKE_030306 prepared by PECHA N; downloaded from ftp.marama.org (username mane-vu, password exchange)3

1.1.3 Mobile Sources

• VMT/Speed: MANEVU_2002_mbinv_02022006_addCT.txt pre pared by PECHAN and NESCAUM; downloaded fromhttp://bronze.nescaum.org/Private/junghun/MANEVU/onroad_ver3_update/MANEVU_V3_update.tar 1.1.4 Point Sources

• Files: MANEVU_Point_SMOKE_INPUT_ANNUAL_SUMMERDAY_041006.tx t and MANEVU_Point_SMOKE_INPUT_ANNUAL_WINTERDAY_041006.tx t prepared by PECHAN were downloaded from ftp.marama.org (username manevu, password exchange) • Fugitive dust correction: This was applied as count y-specific correction factors for SCC’s listed at http://www.epa.gov/ttn/chief/emch/invent/index.html #dust ; the correction factor file gcntl.xportfrac.txt was obta ined from EPA’s CAIR NODA ftp site http://www.airmodelingftp.com (password protected).; this adjustment was performed using the SMOKE programs cntlmat and grwinven to generate an adjusted IDA inventory file used for subsequent SMO KE processing • Corrected the omission of 2,100 tons/year VOC emiss ions from several point sources in NJ. NJDEP provided updated IDA files on June 30 that were used for modeling. 1.2 CENRAP The inventory data were obtained from the CENRAP ft p site in March 2006 and reflect version BaseB of the CENRAP inventory. 1.2.1 Area Sources

• Files: o CENRAP_AREA_SMOKE_INPUT_ANN_STATES_081705.txt o CENRAP_AREA_MISC_SMOKE_INPUT_ANN_STATE_071905.txt o CENRAP_AREA_BURNING_SMOKE_INPUT_ANN_TX_ NELI_071905.txt o CENRAP_AREA_MISC_SMOKE_INPUT_NH3_MONTH_{MMM} _072805.txt where {MMM} is JAN, FEB, ... DEC o CENRAP_AREA_SMOKE_INPUT_NH3_MONTH_{MMM} _071905.txt where {MMM} is JAN, FEB, ... DEC • Fugitive dust correction: This was applied as count y-specific correction factors for SCC’s listed at http://www.epa.gov/ttn/chief/emch/invent/index.html #dust ; the correction factor file gcntl.xportfrac.txt was obta ined from EPA’s CAIR NODA ftp site http://www.airmodelingftp.com (password protected).; this adjustment was performed using the SMOKE programs cntlmat and grwinven to generate an adjusted IDA inventory file used for subsequent SMO KE processing • Note about area and nonroad source SMOKE processing for the CENRAP region: All area source inventories (both annual and month- specific) were processed in4 one step through SMOKE. SMK_AVEDAY_YN was set to N, so seasonal profiles were used to apportion the annual inventor ies numbers by month. This setting was also used for the nonroad processing pe rformed in a separate step. This was necessary since the month-specific files h ad zero in their ‘average-day’ column and the annual total column reflects the “mo nthly emissions as annual totals” as per header line. Therefore, seasonal pro files are used to apportion both the annual and month-specific files. As described b elow, we utilized the temporal profiles and cross-reference files generated by CEN RAP. However, we did not verify that this approach indeed leads to the inten ded monthly allocation of ammonia and nonroad emissions.

1.2.2 Nonroad Sources

• Files: o CENRAP_NONROAD_SMOKE_INPUT_ANN_071305.txt o CENRAP_NONROAD_SMOKE_INPUT_MONTH_{MMM}_071305.txt where {MMM} is JAN, FEB, ... DEC 1.2.3 Mobile Sources

• VMT/Speed files: o mbinv02_vmt_cenrap_ce.ida o mbinv02_vmt_cenrap_no.ida o mbinv02_vmt_cenrap_so.ida o mbinv02_vmt_cenrap_we.ida 1.2.4 Point Sources

• File: CENRAP_POINT_SMOKE_INPUT_ANNUAL_DAILY_072505. txt • Fugitive dust correction: This was applied as count y-specific correction factors for SCC’s listed at http://www.epa.gov/ttn/chief/emch/invent/index.html #dust ; the correction factor file gcntl.xportfrac.txt was obta ined from EPA’s CAIR NODA ftp site http://www.airmodelingftp.com (password protected).; this adjustment was performed using the SMOKE programs cntlmat and grwinven to generate an adjusted IDA inventory file used for subsequent SMO KE processing. 1.3 VISTAS

All VISTAS emission files were obtained from the Al pine Geophysics ftp site. They reflect version BaseG of the VISTAS inventory with the exception of fire emissions which reflect BaseF and BaseD. These files were dow nloaded between February and August, 2006. 1.3.1 Area Sources

• Files:5 o arinv_vistas_2002g_2453922_w_pmfac.txt o ida_ar_fire_2002_vistaonly_basef.ida • Note: the header lines of these files indicate that the fugitive dust correction was already applied, so no further correction was perfo rmed. 1.3.2 Nonroad Sources

• Files: o nrinv_vistas_2002g_2453908.txt o marinv_vistas_2002g_2453972.txt 1.3.3 Mobile Sources

• VMT/Speed file: mbinv_vistas_02g_vmt_12jun06.txt 1.3.4 Point Sources

• Files: o Annual:  egu_ptinv_vistas_2002typ_baseg_2453909.txt  negu_ptinv_vistas_2002typ_baseg_2453909.txt  ptinv_fires_{MM}_typ.vistas.ida where {MM} is 01, 0 2, 03, etc. depending on the month; these annual point fire fil es were generated as part of the VISTAS BaseD inventory and were obtained in January 2005 o Hour-specific:  pthour_2002typ_baseg_{MMM}_28jun2006.ems where {MMM } is jan, feb, mar, etc.  pthour_fires_{MM}_typ.vistas.ida where {MM} is 01, 02, 03, etc. depending on the month; these hourly point fire fil es were generated as part of the VISTAS BaseD inventory and were obtained in January 2005 • Note: No fugitive dust correction was performed for these files. 1.4 MRPO MRPO emissions for SMOKE modeling were generated by Alpine Geophysics through a contract from MARAMA to convert the MRPO BaseK inve ntory from NIF to IDA format. The files were downloaded from the MARAMA f tp site ftp.marama.org (username mane-vu, password exchange) between April and June 2006. 1.4.1 Area Sources

• Files: o Annual:  arinv_mar_mrpok_2002_27apr2006.txt  arinv_other_mrpok_2002_20jun2006.txt o Month-specific:6  arinv_nh3_2002_mrpok_{mmm}_3may2006.txt where {mmm} is jan, feb, etc.  dustinv_2002_mrpok_{mmm}_23may2006.txt where {mmm} is jan, feb, etc. • Fugitive dust correction: This correction was perfo rmed only to the arinv_other_mrpok_2002_20jun2006.txt file using cou nty-specific correction factors for SCC’s listed at http://www.epa.gov/ttn/chief/emch/invent/index.html #dust ; the correction factor file gcntl.xportfrac.txt was obtained from EPA’s CA IR NODA ftp site http://www.airmodelingftp.com (password protected).; this adjustment was performed using the SMOKE programs cntlmat and grwi nven to generate an adjusted IDA inventory file used for subsequent SMO KE processing. • Note about area source SMOKE processing: SMOKE proc essing was performed separately for the annual and month-specific files. For the annual inventory processing, SMK_AVEDAY_YN was set to N, so seasonal profiles were used to apportion the annual inventories numbers by month. For the month-specific inventory processing, this variable was set to Y so that no seasonal profiles would be applied and the inventory numbers in the ‘averag e day’ column would be used. To save a SMOKE processing step, the annual “marine ” inventory “arinv_mar_mrpok_2002_27apr2006.txt” was processed together with the annual “other area source” inventory “arinv_other_mrpok_20 02_20jun2006.txt” even though it technically is part of the nonroad invent ory. 1.4.2 Nonroad Sources

• Files: nrinv_2002_mrpok_{mmm}_3may2006.txt where {m mm} is jan, feb, etc. 1.4.3 Mobile Sources

• VMT/Speed file: mbinv_mrpo_02f_vmt_02may06.txt 1.4.4 Point Sources

• Files: ptinv_egu_negu_2002_mrpok_1may2006.txt • Fugitive dust correction: This correction was perfo rmed only to the arinv_other_mrpok_2002_20jun2006.txt file using cou nty-specific correction factors for SCC’s listed at http://www.epa.gov/ttn/chief/emch/invent/index.html #dust ; the correction factor file gcntl.xportfrac.txt was obtained from EPA’s CA IR NODA ftp site http://www.airmodelingftp.com (password protected).; this adjustment was performed using the SMOKE programs cntlmat and grwi nven to generate an adjusted IDA inventory file used for subsequent SMO KE processing.7

1.5 Canada

1.5.1 Area Sources

• File: AS2000_SMOKEready.txt obtained from ftp://ftp.epa.gov/EmisInventory/canada_2000inventor y • Fugitive dust correction: We applied “divide-by-fou r” correction for SCC’s listed at http://www.epa.gov/ttn/chief/emch/invent/index.html #dust ; this adjustment was performed outside SMOKE with in-house Fortran progr ams. No county/provincespecific correction factors were available for Cana da 1.5.2 Nonroad Sources

• File: NONROAD2000_SMOKEready.txt obtained from ftp://ftp.epa.gov/EmisInventory/canada_2000inventor y 1.5.3 Mobile Sources

• File: MOBILE2000_SMOKEready.txt obtained from ftp://ftp.epa.gov/EmisInventory/canada_2000inventor y • Fugitive dust correction: applied “divide-by-four” correction for SCC’s listed at http://www.epa.gov/ttn/chief/emch/invent/index.html #dust ; this adjustment was performed outside of SMOKE with in-house Fortran pr ograms. No county/province-specific correction factors were av ailable for Canada.

1.5.4 Point Sources There has long been difficulty in obtaining an up-t o-date Canadian criteria emissions inventory for point sources. This is due largely to confidentiality rights afforded to Canadian facilities. Thus far, the most recent inventory of Canadian point sources is rooted in the 1985 NAPAP data and is clo se to two decades old. Because there are a number of high emitting industrial facilities in southern Canada it is of particular importance to have a reasonably accurate inventory of these sources especially when modeling air quality over the Northeast and Midwest United States. Toward this end, an effort was made to obtain more recent Canadian poin t source data and incorporate it into an inventory database, which could then be used for the 2002 OTC air quality modeling. Perhaps the most accurate and publicly accessible s ource of Canadian pollutant data is now available from the National Pollutant R elease Inventory (NPRI) database. This database contains 268 substances. Facilities that manufacture, process or otherwise use one of these substances and that meet reporting thresholds are required to report these emissions to Environment Canada on an annual basis. The NPRI data are available at Environment Canada’s website and can be found at th e link http://www.ec.gc.ca/pdb/npri/npri_home_e.cfm . The page hosts an on-line search engine where one can locate emissions by pollutant or loca tion. In addition, the entire database is available for download as an MS Access or Excel fil e. The NPRI database contains8

numerous pages with a rather comprehensive list of information. Detailed information is available about each facility, including location, activity and annual emissions. In addition, facilities having stacks with a height of 50 meters or more are required to report stack parameters. Unfortunately, one of the limitations of the NPRI d atabase for modeling purposes is that the data are only available at the facility level. Emissions models require process level information, so in order to use this data, a few generalizations had to be made. Each facility has a Standard Industrial Classification ( SIC) code associated with it; however, emissions models require Source Classification Code s (SCC’s). SCC’s are of critical importance as the emissions models use these codes for assignment of temporal and speciation profiles. SIC codes describe the general activity of a facility while SCC codes describe specific processes taking place at each fa cility. While no direct relationship exists between these two codes, a general albeit su bjective association can be made. For the purposes of creating a model-ready inventor y file it was necessary to obtain the whole NPRI database. After merging all the necessa ry components from the NPRI database required in the SMOKE inventory file, the SIC code from each facility was examined and assigned an SCC code. In most cases, o nly a SCC3 level code was assigned with confidence. While this is admittedly a less than desirable process, it does allow for the use of the most recent emissions from the NPRI database to be used in modeling. Furthermore, having some level of SCC ass ociated with these emissions will ensure that they will be assigned a temporal and sp eciation profile by the model, other than the default. Once the model-ready inventory fi le was developed, it was processed through SMOKE. 2. Mobile6 Processing

2.1 MANE-VU 2.1.1 Mobile6 input files

• Month-specific input files were prepared by PECHAN and NESCAUM and were downloaded from http://bronze.nescaum.org/Private/j unghun/MANEVU/onroad_ver3_update/MANEVU_V3_update.tar • Added the line “REBUILD EFFECTS :0.10” to each f ile before the SCENARIO record to override the Mobile6 default set ting of 0.9 (90%) for the “chip reflash” effectiveness 2.1.2 SMOKE/Mobile6 auxiliary files

• SMOKE/Mobile6 auxiliary files were prepared by PECH AN and NESCAUM and were downloaded from http://bronze.nescaum.org/Priv ate/junghun/MANEVU/onroad_ver3_update/MANEVU_V3_update.tar9

2.1.3 Temperature averaging

• Following the setting in the MANEVU_2002_mvref.txt files, the following procedures were used by SMOKE for temporal and spat ial temperature averaging in the calculation of emission factors: o Spatial averaging: temperatures were averaged over all counties that share a common reference county (i.e. Mobile6 input file) o Temporal averaging for May – September emissions pr ocessing: no temporal averaging was used, i.e. day-specific temp eratures were used to calculate emission factors for each day. o Temporal averaging for non-summer-months emissions processing: Temporal averaging over the duration of the episode (i.e. the entire month, see introduction) was used, i.e. monthly average te mperatures were used to calculate the emission factors. 2.2 CENRAP 2.2.1 Mobile6 input files

• Mobile6 input files for the CENRAP region for Janua ry and July were contained in the files central_M6_{MMM}.zip, north_M6_{MMM}.z ip, south_M6_{MMM}.zip, west_M6_{MMM}.zip where {MMM} i s either jan or jul. July input files were used for April – Septemb er processing, while January input files were used for the remaining months • All files were downloaded from the CENRAP ftp site in March 2006. 2.2.2 SMOKE/Mobile6 auxiliary files

• SMOKE/Mobile6 auxiliary files were contained in the files central_M6_RD.zip, north_M6_RD.zip, south_M6_RD.zip, and west_M6_RD.zi p. The SMOKE MCREF, MVREF, and MCODES files were contained in th e file MOBILESMOKE_Inputs.zip. The MCREF and MVREF files w ere combined for the different regions (“central”, “east”, “west”, “ north”) • All files were downloaded from the CENRAP ftp site in March 2006. 2.2.3 Temperature averaging

• The following procedures were used by SMOKE for tem poral and spatial temperature averaging in the calculation of emissio n factors according to the setting in the mvref files: o Spatial averaging: no spatial averaging of temperat ures, i.e. the temperatures for the reference county is used to ca lculate emission factors for all counties that share this reference county ( i.e. Mobile6 input file) o Temporal averaging: Temporal averaging over the dur ation of the episode (i.e. the entire month, see introduction) was used, i.e. monthly average temperatures were used to calculate the emission fa ctors.10

2.3 VISTAS 2.3.1 Mobile6 input files

• Month-specific Mobile6 input files were obtained fr om the Alpine Geophysics ftp site in July 2006. They reflect version BaseG of th e VISTAS inventory. 2.3.2 SMOKE/Mobile6 auxiliary files

• SMOKE/Mobile6 auxiliary files utilized were obtaine d from the Alpine Geophysics ftp site in July 2006. They reflect vers ion BaseG of the VISTAS inventory. 2.3.3 Temperature averaging

• The following procedures were used by SMOKE for the temporal and spatial temperature averaging in the calculation of emissio n factors according to the setting in the mvref_baseg.36k.ag.txt file: o Spatial averaging: temperatures averaged over all c ounties that share a common reference county (i.e. Mobile6 input file) o Temporal averaging: Temporal averaging over the dur ation of the episode (i.e. the entire month, see introduction) was used, i.e. monthly average temperatures were used to calculate the emission fa ctors. 2.4 MRPO 2.4.1 Mobile6 input files

• Month-specific Mobile6 input files for SMOKE modeli ng were generated by Alpine Geophysics through a contract from MARAMA. T hey are based on version BaseK of the MRPO inventory. The files were downloaded from the MARAMA ftp site ftp.marama.org (username mane-vu, password exchange) in May 2006. 2.4.2 SMOKE/Mobile6 auxiliary files

• SMOKE/Mobile6 auxiliary files for SMOKE modeling we re generated by Alpine Geophysics through a contract from MARAMA. They are based on version BaseK of the MRPO inventory. The files were downloa ded from the MARAMA ftp site ftp.marama.org (username mane-vu, password exchange) in May 2006. 2.4.3 Temperature averaging

• The following procedures were used by SMOKE for the temporal and spatial temperature averaging in the calculation of emissio n factors according to the setting in the mvreg_mrpo_basek.txt file: o Spatial averaging: temperatures averaged over all c ounties that share a common reference county (i.e. Mobile6 input file)11 o Temporal averaging: Temporal averaging over the dur ation of the episode (i.e. the entire month, see introduction) was used, i.e. monthly average temperatures were used to calculate the emission fa ctors. 3. Biogenic Emission Processing Hourly gridded biogenic emissions for the 12 km and 36 km modeling domains were calculated by BEIS3.12 through SMOKE, using MC IP-processed MM5 fields for temperature (“TA”, layer-1 temperature), solar radi ation (“RGRND”), surface pressure (“PRES”), and precipitation (“RN” and “RC”). A ‘sea sonal switch’ file was generated by the SMOKE utility metscan to determine whether wint er or summer emission factors should be used for any given grid cell on any given day. Winter emission factors are used from January 1 st through the date of the last frost and again from the data of the first frost in fall through December 31 st . Summer emission factors are used for the time per iod in between. This calculation is performed separately f or each grid cell. 4. Temporal Allocation

4.1 MANE-VU

4.1.1 Area and nonroad sources

• Generated as part of the MANE-VU version 1 inventor y • amptpro.m3.us+can.manevu.030205.txt • amptref.m3.manevu.012405.txt • downloaded from ftp.marama.org (username mane-vu, password exchange) in January 2005 4.1.2 Mobile sources

• MANEVU_2002_mtpro_02022006_addCT.txt • MANEVU_2002_mtref_02022006_addCT.txt • prepared by PECHAN and NESCAUM and downloaded fromhttp://bronze.nescaum.org/Private/junghun/MANEVU/onroad_ver3_update/MANEVU_V3_update.tar 4.1.3 Point Sources

• Based on the same files as for the MANE-VU area and nonroad temporal files listed above, but added the CEM-based 2002 state-sp ecific temporal profiles and cross-references for EGU sources for the MANE-VU st ates that were generated by VISTAS for their BaseD modeling and obtained in February 2005. • No CEM-based hour-specific EGU emissions were utili zed 4.2 CENRAP The following temporal profiles and cross-reference files were used:12

• Area and nonroad sources: o amptpro.m3.us+can.cenrap.010605_incl_nrd.txt o amptref.m3.cenrap.010605_add_nh3_and_nrd.txt • Mobile sources: o mtpro.cenrap.v3.txt o mtref.cenrap.v3.txt • Point sources: o ptpro.{QQ}.cenrap_egus_cem.00-03avg.121205.txt wher e {QQ} is Q1 for January/February/March, Q2 for April/May/June, etc. o ptref.{QQ}.cenrap_egus_cem.00-03avg.121205.txt wher e {QQ} is Q1 for January/February/March, Q2 for April/May/June, etc. • All files were downloaded from the CENRAP ftp site in March 2006. 4.3 VISTAS The following month-specific temporal profiles and cross-reference files were used: • Area and nonroad sources: o atpro_vistas_basef_15jul05.txt o atref_vistas_basef_15jul05.txt • Mobile sources: o mtpro_vistas_basef_04jul05.txt o mtref_us_can_vistas_basef_04jul05.txt • Point sources: o ptpro_typ_{MMM}_vistasg_28jun2006.txt where {MMM} i s jan, feb, mar, etc. o ptref_typ_vistas_baseg_28jun2006.txt • These files were obtained from the Alpine Geophysic s ftp site. They reflect version BaseG of the VISTAS inventory for the point source allocation files and version BaseF for the area, nonroad, and mobile sou rce allocation files. These files were downloaded between February and July, 20 06. 4.4 MRPO The following month-specific temporal profiles and cross-reference files were used for all source categories: • amptpro_typ_us_can_{MMM}_vistas_27nov04.txt where { MMM} is jan, feb, mar, etc. • amptref_2002_us_can_vistas_17dec04.txt • These files were obtained from VISTAS in January 20 05 and reflect their BaseD modeling. No updated temporal profiles or cross-ref erence files were developed for use with the MRPO BaseK inventory. 4.5 Canada For Canada, the SMOKE2.1 default temporal profiles and cross-reference files (amptpro.m3.us+can.txt and amptref.m3.us+can.txt) w ere utilized.13

5. Speciation The same speciation profiles (gspro.cmaq.cb4p25.txt ) and cross-references (gsref.cmaq.cb4p25.txt) were utilized for all regio ns and all source categories. Different versions of these files were obtained (SMOKE2.1 def ault, EPA-CAIR modeling, VISTAS, CENRAP and MANE-VU) and compared. After com paring the creation dates and header lines of these files, it was determined that the EPA-CAIR and MANE-VU files had the most recent updates, and consequently the final speciation profile and crossreference files used for all regions and source cat egories was based on the EPA-CAIR files with the addition of MANE-VU specific updates

. 6. Spatial Allocation

6.1 U.S. The spatial surrogates for the 12km domain were ext racted from the national grid 12km U.S. gridding surrogates posted at EPA’s website at http://www.epa.gov/ttn/chief/emch/spatial/newsurrog ate.html The gridding cross-references were also obtained fr om this website, but for the processing of MANE-VU area source emissions, MANE-V U specific cross-reference entries posted on the MARAMA ftp site were added.

6.2 Canada The spatial surrogates for Canadian emissions for t he 12km domain were extracted from the national grid 12km Canadian gridding surrogates posted at EPA’s website at http://www.epa.gov/ttn/chief/emch/spatial/newsurrog ate.html The gridding cross-references were also obtained fr om this website.

Reference: Pechan: (2006) Technical Support document for 2002 MANE-VU SIP Modeling inventories, version 3. Prepared by E. H. Pechan & Associates, Inc. 3622 Lyckan Parkway, Suite 2005, Durham, NC 27707.