Proposed Rule: Mandatory Reporting of Greenhouse Gas EmissionsDocumentation for October 2009 Site Visit to DuPont Corpus Christi, Texas Regarding Fluorinated GasProductionDate:19 October 2009Staff Contact Information (Name, email, phone #):Deborah Ottinger, EPA, 343-9149,Ottinger.deborah@epa.gov; Karen Schaffner, RTI,ksschaffner@rti.orgName of Organization (Attach list of all attendees namesand emails if possible):Tim McDaniel, Mark Kaufman, Bob Blaschke, Steve Kaaffman,Arky Andrews, Kristie Glenig., Michael Bates, Jim O’Connor, DuPontSummary of Discussion(e.g., applicability, reporting requirements, etc.):The purpose of the site visit was to discuss emission estimation techniques and analytical methods available to measure fluorinated gas emissions.The DuPont representatives noted the following:DuPont produces fluorocarbon products at multiple sites andnoted that they manage highly hazardous processes that useHF, HCl, and Cl2. Thefluorinated and chlorinated compounds are hazardous and employee safety is their number one concern. The Corpus Christi site is an exceptionalfacility and is considered a flagship plant. This siteproduces HFC-134a and HFC-152a. There is an intermediates process area at the site, whichproduces feedstream for the HFC-134a process. It is anticipated that the facility would be subject 40 CFR part 98, subpart L and subpart OO. Thefacility is considered an area source for HAP. The facility has invested in emission controls. The site conducts extensive vent recovery; emissionsare vented to the thermal converter. The site has worked to reduce fugitive emissions, for example from equipment leaks. The site conductsclosed loop sampling and tank car loading and unloading.The requirement in the proposed rule to conduct daily samples is a significant issue for the facility. The facility prefers not to sample processstreams daily but noted they could sample occasionally,for example annually rather than daily. A reduced frequency is much preferred asfrequent sampling increases the risk to employees from hazardous stream constituents. Process streams have beenwell-characterized and are wellunderstood based on process chemistry, and the process flow sheet identifies compounds. These process flow sheets couldbe used as analternative to daily sampling.In tracking production, the facility conducts a number of “cycle checks” or “true ups.” They have two systems thatallow tracking andmeasurement of production. One system is a process monitoring system along with a digital control system (DCS) where process monitoring datais stored; it provides a data historian and archiving.The other system is a financial tool to determine the amount of material produced andavailable to sell. This system is the official depository of production information. Sometimes the two tracking systems don’t align exactly (werenot intended to match up). The facility conducts a weekly“check” or “true up” (requires 2 days to complete the check)and conducts a materialbalance or mass balance on a monthly basis to close theloop on raw material inputs, losses, and product generated.They noted they do notconduct material balances on a daily basis. Staff notedthat daily mass balance will lead to an increase inerrors, for example, negative balances;this is due to multiple tanks, multiple transmitters, and movement of materials through the process and lagtimes.Currently, the facility collects dataon the plant’sphysical inventory, flow transmitters,and theprocessdesign for product and yield. Physicalinventory data includes storage weights and tank levels.Flow transmitters that are used include orifice meters (with lower accuracy than the 0.2percent required in the April 2009 proposed rule); magnetic meters; and Coriolis meters (these have lower maintenance,high accuracy devices,although some difficulties include corrosive material contact and the unit not being compatible with all streams).The accuracy and precision foreach of these types of flow meters vary. The facilitywould use Coriolis meters in most every application if they could; a Coriolis has 2 leak points(i.e., 2 flanges) while an orifice meter would have several leak points (several flanges). A typical 1 inch to3 inch Coriolis meter made ofHastelloy steel would be approximately $7,000 to $10,000.Staff noted that a mass balance that averages the yield for all raw materials is problematic. Invariably, the yield for one raw material input to theprocess will be high, for example on the organic, while theyield for another will be lower. If you must average them,then you get a lower overallyield that is not representative. It may be better toestimate a “weighted mass” average yield that would bemore true.Most processes are continuous. The facility may produceproducts in different equipment for a particular campaign. The facility has a philosophybased on zero emissions that emphasizes waste minimization, pollution prevention and reduction, recycle, and treatment. As mentioned earlier,equipment leak emissions have been reduced by reducing the number of flanges/valves, and increasing use of seal-less pumps, bellows valves, andincreased welded piping. For the most part, point sources are vented to an air pollution control device and are therefore a smaller portion of thetotal facility emissions. Because the point source emission levels are small, equipment leak emissions are actually a larger portion of the totalfacility emissions. This likely is a different emissions profile than may be seen at other facilities.Emissions are reported to the TCEQ each year. Emissions reporting at the facility is based on a number of methods, including air permitassumptions, EPA AP-42 emissions factors and calculation equations, SOCMI factors, etc., monthly and yearly production totals, average andmaximum flow rates, in some instances the valve positions for vents or lines, the destruction efficiency of controldevices such as scrubbers,recovery devices, and the thermal converter, vendor equipment specifications, and process flow sheets (pilot plant data,plus engineeringknowledge). Overall, the facility uses AP-42 emission factorsand calculations in permitting to estimate potential to emit emissions. Fordetermining the flow rates to the thermal converter, some vent lines have flow meters, while for others the valve position is tracked to determinethe flow rate. The facility uses standard chemical engineering calculations in addition to AP-42 equations. The facility uses actual site-specificflows, compositions, temperatures, molecular weights, etc.to estimate emissions. To develop emissions factors, the facility uses the theoreticalprocess chemistry and models (ASPEN) to determine and characterize compounds and concentrations for estimating emissions.For equipment leak monitoring, the facility conducts monitoring under different regulatory programs. The equipment leaks for the HFC-134aprocess are subject to a state regulation, the TCEQ 28M program (covers lines that are 2 inches in diameter and greater), and the equipment leaksfor HFC-152a are subject to Federal regulation in 40 CFR part 60, subpart VV; the rule allows “skip” monitoring provisions when there are lessthan 2 percent leakers, where monitoring that is requiredeach quarter would be required less frequently, forexample, semi-annually, when theprocess meets the criteria for less frequent monitoring. The facility noted that they use default emissions factors to determine potential-to-emitemissions for equipment leaks and they use the correlationequations for reporting actual emissions to TCEQ. The facility uses an LDARcontractor who conducts monitoring and estimates the annual emissions. Methane is used as the calibration gas.For tanker car loading, the facility uses AP-42 loading equations to estimate emissions.The thermal converter was installed in 1991 to 1992 and an initial performance test was conducted in 1994. The device destroys fluorinatedcompounds. Parametric monitoring is conducted to ensure theconverter is operating at compliance levels. Staff notedthat it is difficult tomeasure and speciate fluorinated compounds in the inletvent stream to the Thermal Convertor due to acid compoundsin the streams and theseinlet compounds are not currently speciated. The fluorinated gas concentration in the inlet stream to the thermal convertor will vary or fluctuate.Annual or quarterly sampling and recordkeeping will provide more useful data than daily sampling and recordkeeping. Daily measurements, i.e.,sampling and analysis, for streams that contain hazardouscompounds significantly increase operator exposure to highly toxic materials.The facility provided input on subpart OO. The existing measurement instruments meet ±1 percent. Unfortunately, the facility would still berequired to speciate the onsite thermal convertor outlet streams; this problematic because the stream contains acids (HF) and would need to bescrubbed prior to measurement. This requires installing a sampling port along with an automated sampling and GC system or along with conductof manual sampling. The capital costs for a GC instrument are high. Use of manual sampling, or process stream grab sampling, requiresadditional manpower hours (and $) to suit up in personal protective equipment (PPE). Some processes with HF or otherhazardous componentswould require that operators wear their PPE, including an acid suit and a breathing apparatus. These suits arecumbersome to work in, and requireadditional time and sometimes multiple operators to complete a task. The facility does not currently conduct periodic process sampling. The PPEsuits are used for process breakdown, shutdowns, or maintenance events.The facility provided input on the subpart L compliance schedule. The subpart L compliance schedule is challenging for them.Because they havemultiple processes that include HF, HCl, Cl2, and flammable compounds, they follow a “management of change” process, those expected inOSHA Process Safety Management (PSM) and EPA Risk Management Program (RMP). A Change of Design (COD) implementation effort takestime, somewhere between 6 to 12 months cycle time. Thisrule requires a 12 month cycle time, which may be difficult to implement within theother programs’ management of change processes. EPA shouldconsider the business and practical implementation of incremental improvementthat is consistent with other programs.The facility also noted that multiple facilities will be attempting to procure measurement equipment at thesame time, which will be burdensomefor the industry and certain vendors/equipment manufacturers. Staff also noted that there is no viable technology available to measure HFC’s inacid streams (HF). For GC/MS, there are interference issues when measuring multiple fluorinated gases. Staff suggested it may be better tocharacterize the waste stream.Staff noted that there are no HFC emissions from intermediate processes at the site; these intermediate processes generate CFC as byproducts.There are no fluorinated GHG emissions from production ofCFCs or HCFCs.The DuPont facility in Fayetteville, North Carolina also has hazardous compounds (odorless, colorless, toxic) andconducts a high level of PSM.The Fayetteville sitemanufacturespolymers or HFEs (Teflon processes)andemits HFE’s, and the site will havesomefluorinated gases that donot have GWPs assigned. The DuPont facility in Parkersburg, West Virginia manufactures polymers or HFEs (Teflon processes).Staff reviewed several points from the discussion: the monitoring device or measurement device accuracy is not the same asthe system accuracy;when there are multiple measurement devices, the precision is additive; the material balance for a continuous processcan be negative if done on adaily basis; suggested theoretical instrument accuracy andprecision of ±1 percent; and monthly resolution of mass ormaterial balances isappropriate.[Additional information is contained in the Confidential Addendum to the site visit containing additional notes.]Written Comments Provided?Did they also submit to Docket?NoDate sent to EPA-CCDNone

# EPA Docket No. EPA-HQ-OAR-2009-0927

The following information is located in the confidential ity files of the Director, Climate

Change Division, U. S. Environmental Protection Agency, Wa shington DC. This information is

confidential pending final determination by the Administrator and is not available for public

inspection.

Site Visit Notes from DuPont Corpus Christi, TX, D. Ot tinger, U.S. EPA and K.

Schaffner, RTI International. Dated October 19, 2009.

The notes contain additional information about the D uPont fluorinated gas production

processes and the facility’s experience with emission estimation for fluorinated GHG. The

confidential material is comprised of 13 pages of notes.