Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 3 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com TABLE OF CONTENTS
I. EPA Must Give Due Consideration to the Clean Air Act’s Principles of Source Operations and Performance Data as it Reconsiders the PVC MACT .......................................................................6 A. Emissions Standards Must Encompass the Industry’s Product Variability ........................................................6 B. The Agency Should Either Subcategorize PVDC Production Facility or Exclude its Data from Consideration .7 C. New Source Limits ..........................................................................................................................................11 D. The Data is the Data: Increased Limits on Reconsideration are Permissible and in this Case, Warranted.....16
II. Reconsideration of Process Wastewater Limits .............................................................................17 A. Product Variability Has Significant Impacts on Wastewater HAP Profiles.......................................................19 B. Alternative Compliance Demonstration for VCM and TOHAP in Wastewater .................................................24 1. Proposed Solution: EPA Should Allow Monthly Compliance Averaging .................................................25 2. Also Apply Compliance Averaging to Wastewater Stream Treatment Determinations ...........................26 C. The Wastewater Limits Must Allow for the Production of Copolymers and the Use of Suspending Agents and Other Ingredients that Contain HAPs.............................................................................................................26 1. 110 ppm TOHAP Limit Would Foreclose VAM Copolymers ...................................................................27 2. 110 ppm Limit Would Foreclose the Use of Several Critical Ingredients ................................................29 3. The Reconsidered Rule Should Allow Flexibility for Reducing the Emission of Soluble HAPs Including Methanol.................................................................................................................................................36 D. EPA Should Retain the VCM Limit for Existing Major and Area Source Facilities...........................................38
III. Combined Process Vents ..................................................................................................................39 A. Applicability of PVC-Combined Limits to Non-PVC Facilities Violates the Clean Air Act and Fundamental Notions of Fairness and Due Process............................................................................................................40 B. At a Minimum, EPA Must Clarify that the PVC-Combined Emission Limit Apply at the Outlet of the Emission Control Devices .............................................................................................................................................42 C. Building Block Approach to Combined Limits Overcomes Statutory and Data Deficiencies ...........................46 IV. Bypasses from Closed Vent Systems ..............................................................................................48 A. The Recovery System is Not Part of the Closed Vent System........................................................................49 B. An Exemption for Maintenance-Type Valves Must be Included ......................................................................50 C. Equipment Openings Are Not Bypasses .........................................................................................................51
V. Emission Profiles................................................................................................................................51

VI. Vent Gas Absorbers ...........................................................................................................................55 VII. Pressure Relief Device Requirements..............................................................................................58 VIII.Leak Detection and Repair (“LDAR”) for Pressure Vessels ..........................................................60 IX. Vapor Balancing .................................................................................................................................62 X. Issues Raised by the Other Petitioners............................................................................................64 A. Organic HAP Emission Limits .........................................................................................................................64 B. EPA’s Methodology in Promulgating the PVC NESHAP for Area Sources on April 17, 2012 is Consistent With the CAA .........................................................................................................................................................66 1. EPA’s promulgation of the PVC NESHAP for area sources includes some emission limits that are lower than the major source emission limits.....................................................................................................67 2. EPA should have included what the Agency characterizes as “synthetic minor sources” in the MACT floor for area sources, not major sources. ..............................................................................................68 3. The Working Group does not object to EPA’s inclusion of an HCl limit for process vents in the GACT standard..................................................................................................................................................69 4. Considerations for Major Sources Also Apply to Area Sources ..............................................................69 C. Reasonable Estimates Used to Set the MACT Floors.....................................................................................69
XI. Conclusion ..........................................................................................................................................71Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 4 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com ATTACHMENTS

Attachment No. Description

Attachment I Technical Impacts of PVC MACT Comments on Changes in

Resin Properties Affecting Downstream Users

Attachment II VI Aggregated PVC MACT S114 WW Data

Attachment III Emissions of High-Solubility VOCs from Municipal Sewers,

Report for Tischler-Kocurek and The Pharmaceutical Research and Manufacturers of America (1996)

Attachment IV Wastewater Management Fact Sheet: Denitrifying Filters;

and Methanol, Denitrification and Safety

Attachment V Process Vent Limit Calculations Based on Mass Flow

Attachment VI Compiled Revisions to the Rule for Equipment Leaks and

Storage VesselsReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 5 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com

FIGURES

Figure No. Description Figure 1 OxyVinyls Deer Park 30-Day Acetophenone Figure 2 OxyVinyls Deer Park 30-Day Vinyl Chloride Figure 3 OxyVinyls Pasadena 30-Day Vinyl Chloride Figure 4 Formosa SPVC 30-Day Vinyl Acetate Figure 5 Formosa Delaware 30-Day Vinyl Acetate Figure 6 OxyVinyls Pasadena 30-Day Methanol Figure 7 Methanol Performance of Facilities Using Methanol-Based

Ingredients Figure 8 PVC Producers Demonstrating Variability in Methanol Figure 9 PVC MACT/HON Overlap

TABLES

Table No. Description
Table 1 PVC MACT Standards Applicable to New PVC-Only Suspension

Facilities Table 2 Facility Resin Ranking by Analyte (excluding non-detects) Table 3 Final PVC MACT Wastewater Stripper Outlet Concentration Limits

(in ppmw) Table 4 PVC Industry Wastewater Stripper Configurations Table 5 Facility Wastewater Ranking by Analyte (including non-detects) Table 6 OxyVinyls Deer Park PVC – Wastewater Stripper VCM In and Out Table 7 Methanol Concentration Across Product Types Table 8 TOHAP and Methanol Limits Based on Ingredient Use Table 9 Comparison of Best Performance Rankings Table 10 Product Mix Addressed by 2013 Section 114 Wastewater Sampling Table 1 1 Comparison of 2008 and 2013 Wastewater Data Table 1 2 Potential PVC Combined Limits Table 1 3 Proposed Recalculated PVC-Combined Process Vent Limits Table 1 4 Example Blended Limit Calculation for THC Table 15 Example Blended Limit Calculation for Vinyl Chloride Table 16 Proposed Mass-Based Process Vent Emissions Limits Table 1 7 Comparison of Major and Area Source Process Vent Limits Table 1 8 Comparison of Major and Area Source Resin and Process

Wastewater LimitsReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 6 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com I. EPA Must Give Due Consideration to the Clean Air Act’s Principles of Source Operations and Performance Data as it Reconsiders the PVC MACT
As the docket record can attest, 4 this rulemaking has raised complex issues that reflect the intricate relationship between the products and processes encompassed daily by this source category, on the one hand, and the wide array of customer applications and requirements that rely on them, on the other. We very much appreciate the Agency’s willingness to consider the critical role played by the wide array of PVC resins in the U.S. economy. As you consider our comments and recommendations below, please recognize that we have sought throughout this rulemaking to employ the Agency’s general MACT methodology in light of the statutory text and legal precedents.
A. Emissions Standards Must Encompass the Industry’s Product Variability The production of PVC and copolymer resins is significantly more complex than most of the commodity chemicals and other production processes EPA has regulated under the MACT framework. In many instances, resin recipes have been specifically formulated to meet precise customer material specifications. These specifications relate not only to the properties and performance characteristics of the ultimate product ( compare pipes and fittings, windows, doors, medical applications, wires and cables, and automotive upholstery, etc.), but also to the machinery and processes used to manufacture these products. As we noted in the Working Group comments on the proposed PVC MACT rule, a particular grade of resin may be developed for a particular type of equipment ( e.g. , single screw or twin screw profile extruders, co-extrusion, sheet extrusion, calendared films and sheet, plastisols for dipping and coatings, thin wall or heavy wall injection molding, slush molding, and others). 5

As a result, HAP emissions profiles may vary significantly, not only by resin type, but also by individual recipe. These differences are not driven by control device performance, but rather by the types of ingredients needed to meet a complex combination of process parameters and product characteristics to ensure that the finished resin complies with customer specifications. As the Agency noted: [T]he data clearly show that there are significant differences in the concentrations of vinyl chloride and other HAP that remain in the various types of resins following stripping. The differences in the concentrations of vinyl chloride and other HAP that remain in the various resin types are a direct consequence of several factors related to the overall process to produce each resin type. These factors include: The different raw materials necessary to produce each resin type, the unique process chemistry required to produce each resin type, the process conditions

4 See generally Docket No. EPA-HQ-OAR-2002-0037.

5 See Docket Document No. EPA-HQ-OAR-2002-0037-0146 at p. 9.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 7 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com required to produce each resin type and differences in the morphology of the resin particles following polymerization. 6 As the Working Group noted in its comments to the proposed PVC MACT rule, 7 individual formulations are not developed simply to satisfy the whim of downstreamcustomers. A change in resin recipe or manufacturing process can affect critical endproduct characteristics that are called for by building and other codes, third party standards, and other regulatory specifications. These specification and product parameters do not merely drive selection of the broader resin subcategories ( e.g. , dispersion, suspension, etc.), they also dictate the polymerization reactor ingredients needed to impart several critical resin characteristics, including particle size, porosity, inherent viscosity, thermal stability, bulk density, and color. We discuss these considerations in greater detail in Attachment I

. In this regard, while it is axiomatic that the Act requires facilities to comply 100% of the time with emissions limits that are based on the average level actually achieved by the five best performing facilities, no process is without variability. Because the sampling and testing data used to set MACT compliance levels represents only a snapshot in time, emissions limits developed by EPA must, where applicable, account for the daily statistical variability missing from time-limited data sets, daily variations in the process, and the wide array of resins produced by the industry in its entirety with those few made at individual plants. Indeed some facilities produce a large volume of a few, or in some cases, just a single resin, whereas other facilities produce as many as 20 different resins to meet their customer demands. While vinyl chloride is a common ingredient amongst these resins, other ingredients produce very different HAP emissions profiles, which nevertheless are controlled by the technology used to meet vinyl chloride limits. We address these principles in greater detail below and appreciate the Agency’s diligence and efforts in this regard.
B. The Agency Should Either Subcategorize PVDC Production Facility or Exclude its Data from Consideration At its July 23, 2013 meeting with the Working Group, the Agency expressed concerns about subcategorizing the Dow Midland, Michigan facility, which produces polyvinylidene chloride (“PVDC”) copolymer resins as part of its SARAN TM product line. Specifically, EPA staff expressed concerns about creating a subcategory that contains only one facility. If Dow was producing the same product as PVC polymer producers, this concern might be valid. In this case, however, Dow is the sole U.S. producer of a unique product, with distinct chemical and performance properties and HAP profiles. Indeed as the D.C. Circuit noted: While acknowledging that EPA has authority to devise the means of deriving this estimate, we made clear that the method the Agency selects

6 National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers Production , 77 Fed. Reg. 22,848, 22,870 (April 17, 2012).

7 Docket Document No. EPA-HQ-OAR-2002-0037-0118; Docket Document No. EPA-HQ-OAR-2002- 0037-0146; Docket Document No. EPA-HQ-OAR-2002-0037-0168.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 8 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com must “allow[ ] a reasonable inference as to the performance of the top 12 percent of units.” ...We emphasized that EPA must show not only that it believes its methodology provides an accurate picture of the relevant sources’ actual performance, but also why its methodology yields the required estimate...In evaluating EPA’s standards, we reiterated Sierra Club’s central holding that “to comply with the statute, EPA’s method of setting emission floors must reasonably estimate the performance of the relevant best performing plants.” 8
Recognizing the Agency’s concerns about creating a “subcategory of one,” the Working Group nevertheless submits that Dow’s SARAN process and equipment differ so widely from the rest of the PVC industry that the facility simply is not a relevant plant for purposes of setting emissions limitations for the entire PVC industry.
The Dow Midland facility has three SARAN production lines of about the same size. Two of these lines produce a copolymer that uses vinylidene chloride (“VDC”) as the primary monomer and methyl acrylate as the minor co-monomer. The third line alsouses VDC as the primary monomer, but vinyl chloride as the minor (less than 25%) comonomer. Indeed, only Dow uses vinylidene chloride to produce copolymers in the U.S., and produces the only copolymer where vinyl chloride is not the predominant monomer. In addition, the VDC/vinyl chloride line produces only one general type of product, but may produce other grades of product by adjusting raw material feed rates and operating conditions, whereas most other facilities in the industry produce multiple resin grades via multiple recipes.
The equipment configuration at the Dow Midland facility also differs widely from the facilities of other Working Group members. First, unlike all other U.S. suspension type PVC facilities, which use dedicated resin strippers, SARAN resin is stripped in the batch polymerization reactor, which results in a significantly different HAP profile. (The difference in profile is likely due to the different comonomer used). Resin stripping is also a batch stripping process, which could impact the HAP profile.
Secondly, the Midland facility uses a vapor-liquid separator, more commonly referred to as a “knockout pot,” to manage its wastewater. Steam is used to heat the knock out pot by a steam jacketing system and nitrogen is injected into the knock out pot to remove VOC and HAP from the water prior to the wastewater being discharged. In contrast, all other PVC facilities use wastewater strippers which inject live steam directly into the wastewater. Thus, the SARAN wastewater HAP profile necessarily reflects only a very limited number of HAPs whose presence and concentration will notvary significantly. Although this profile is very representative of the Dow facility’s day-today operations, it is not representative of any other facility in the industry. Similar concerns arise over EPA’s use of the Dow Midland facility to develop PVC-combined process vent limits.

8 Cement Kiln Recycling Coal v. EPA , 255 F.3d 855, 862 (D.C. Cir. 2001).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 9 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Several PVC production facilities share process vent control devices with facilities in other source categories. In the proposed PVC MACT, the Agency did not differentiate between facilities that share process vents and those that do not. In the final rule, however, EPA promulgated separate emissions limits for PVC-only process vents and PVC-combined process vents. It is important to recognize that except for the Dow Midland facility, all other PVC-combined facilities vent to control devices at EDC/VCM facilities that are subject to the Hazardous Organic NESHAP (“HON”). In contrast, Dow’s VDC/VC line at Midland vents to the control device for its VDC/MA lines, which are subject to the Miscellaneous Organic NESHAP (“MON”). The Dow Midland facility also differs from other PVC combined facilities in that its control device (”thermal oxidizer”) handles a vent stream from yet another source category. According to Dow, a small vent from a process that is subject to the Pesticide Active Ingredient MACT, 9 also is routed to the thermal oxidizer at the Dow Midland facility. Thus, the control device receives vents from areas that are regulated by the PVC, MON, and PAI MACTs.

Moreover, the thermal oxidizer at the Midland facility simply is not comparable to the thermal oxidizers used at other facilities with PVC-combined process vent streams. The thermal oxidizers used at the EDC/VCM facilities in the PVC-combined subcategory ranged in throughput capacity from 29.7 million British Thermal Units per hour (“mm BTU/hr”) to 87 mm BTU/hr. 10 In contrast, the dramatically lower throughput capacity of the Midland thermal oxidizer is approximately 3 mm BTU/hr, which places it at the lower end of the throughput range of process vent control devices for PVC-only facilities (2 mm BTU/hr to 12.7 mm BTU/hr). It should be self-evident that the Dow facility cannot be included in the PVC-only category or in a putative category for small process vent control devices because of the multiple streams handled by the facility. Accordingly, the Dow Midland facility should be subject to separate combined process vent limits.
It is worth noting that the Midland facility arguably could be subject to the MON. Of relevance here, the Agency, on July 16, 1992, published its initial list of 174 categories of major and area sources, including Polymerized Vinylidene Chloride Production, which would be subject to MACT emissions standards. 11 The Agency defined the distinct category to cover “any facility which manufactures a homopolymer or copolymer using vinylidene chloride as the principle monomer unit.” 12 As part of the source category background documentation, EPA included PVDC production: Vinylidene chloride monomer is polymerized with a variety of other monomers to produce copolymers with special properties. VDC copolymers can be divided into high VDC polymers, generally containing

9 40 C.F.R. Part 63, Subpart MMM.

10 Some facilities have smaller (20 mm BTU/hr) thermal oxidizers as an emergency back up, but these units were not tested.

11 57 Fed. Reg. 31,576.

12 EPA, Final Report: Documentation for Developing the Initial Source Category List, p. A-62, EPA-450/3- 91-030 (July 1992).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 10 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com 70 to 95 percent VDC, and low VDC polymers, generally containing 10 to 70 percent VDC...High VDC polymers are also used to make Saran films which can be used alone or laminated to other plastic films. The comonomers most commonly used to produce high VDC polymers are vinyl chloride, acrylic acid, acrylic esters and acrylonitrile. 13
The Agency specifically identified the Dow Midland facility as a facility that produces high VDC polymers. 14 EPA retained this distinction when it decided to include PVDC production as a miscellaneous organic chemical process subject to the MON: The following source categories have been subsumed into the Miscellaneous Organic Chemical Manufacturing source category: benzyltrimethylammonium chloride production, carbonyl sulfide production...polymerized vinylidene chloride production...Along with these 22 source categories, the Miscellaneous Organic Chemical Manufacturing source category was also defined to include other organic chemical manufacturing processes which are not being covered by any other maximum achievable control technology standards

. 15
Finally, the Agency also should be consistent in its analytical approach and use of data. Specifically, the Working Group understands that the combined process vent thermal oxidizer at the Midland facility underwent a stack test in response to the Agency Section 114 request on January 19 and 20, 2010. At the time of the 2010 test, however, the process associated with the small vent stream referenced above, was subject to the Pharmaceutical MACT. It is important to note that the vent stream from this vent source contained primarily nitrogen and non-halogenated organic hydrocarbons and thus significantly decreased the concentrate of the HAPs addressed by the PVC MACT. Thus, EPA does not have data to reflect the current process, which is governed by the PAI MACT.
We also understand that the Agency had HCl data from a 2008 stack test at the Dow facility, which it did not use in calculating the HCl limit for PVC-combined process vents. Accordingly, a strong basis and precedent exists for the Agency to determinethat the remaining Dow data is not comparable to that obtained from other PVCcombined facilities.

In short, not only does the Agency have the authority to subcategorize the Dow facility with respect to process vent and wastewater emissions limits, it must do so. In the alternative, the Agency could determine that all three VDC lines at the Midland plant are subject to the MON. Should the Agency agree with this approach, then the Working Group submits that the final rule definition of polyvinyl chloride copolymer should be revised to clearly exclude the VDC process, as follows:

13 EPA, Locating and Estimating Air Emissions From Sources of Vinylidene Chloride, p. 33, EPA-450/4- 84-007k (September 1985).

14 Id. at 51.

15 National Emission Standards for Hazardous Air Pollutants: Revision of Source Category List Under Section 112 of the Clean Air Act, 70 Fed. Reg. 37,819, 37,821 (June 30, 2005).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 11 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Polyvinyl chloride copolymer means a synthetic thermoplastic polymer that is derived from the simultaneous polymerization of vinyl chloride and another monomer such as vinyl acetate. Polyvinyl chloride copolymer is produced by different processes, including, but not limited to, suspension, dispersion/emulsion, suspension blending, and solution processes. Polyvinyl chloride copolymers do not include high-content vinylidene chloride copolymers, which are regulated as a separate source category subject to subpart FFFF of this Part.The Agency also should provide such PVDC facilities with a period of time to reimplement the MON requirements.
Should the Agency nevertheless find that these options are infeasible; the Working Group submits that the preceding discussion provides a sufficient basis to find that the Midland facility data is not relevant to setting a PVC-combined emission limit.

C. New Source Limits The extensive development and increasing abundance of natural gas and crude oil extracted from shale formations has placed the U.S. PVC industry in a very advantageous position relative to its global competitors. This quickly evolving economic opportunity has led many in and outside the industry to inquire about the feasibility of building new Greenfield PVC facilities. The problem, however, is that no new economically viable PVC facility can be built under the current emissions limits EPA has promulgated for new sources. As we discuss briefly below and in Sections II-IV, some of the new source limits are an amalgamation of emission points from different facilities that in many cases were the best performing facilities for that emission point analyte because of a limited product mix. Accordingly, the new source limits do not reflect the performance configuration of any source actually in existence in the PVC industry.
In developing emissions standards for new sources, Section 112(d)(3) directs the Agency to look to the performance of the best source in a source category or subcategory: The maximum degree of reduction in emissions that is deemed achievable for new sources in a category or subcategory shall not be less stringent than the emission control that is achieved in practice by the best controlled similar source... 16
If the Agency seeks to impose more stringent standards than those achieved in practice by the best controlled similar source, Section 112(d)(2) requires the Agency to conduct a “beyond the floor” analysis that takes into consideration the cost of meeting the more stringent limits.
It is worth noting that the term “stationary source,” as it is used in Section 112 of the Act has the same meaning as under Section 111(a), meaning “any building,

16 42 U.S.C. § 7412(d)(3).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 12 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com structure, facility, or installation which emits or may emit any air pollutant.” 17 The statute also makes clear that “existing sources,” as used in the Section 112(d) MACT provisions, “means any stationary source other than a new source.” 18 By contrast, in setting standards for new and existing sources, Section 112(d)(2) authorizes the Agency to impose restrictions and other measures on HAPs “when released from a process, stack, storage or fugitive emissions point.”
As a general matter, when Congress uses two different terms in the same provision, it is generally presumed that Congress acted intentionally and purposefully. 19 Accordingly, the term “source” must have a meaning separate, apart, and more inclusive than the lesser inclusive terms “stack,” “emission point,” or even resin stripper or process vent. And indeed, the final PVC MACT clearly articulates the Agency’s understanding of Congressional intent by defining “affected source” under the rule as: The polyvinyl chloride and copolymers production affected source is the facility wide collection of PVCPU, storage vessels, heat exchange systems, surge control vessels, wastewater and process wastewater treatment systems that are associated with producing polyvinyl chloride and copolymers. In addition, “A statute should be construed so that effect is given to all its provisions, so that no part will be inoperative or superfluous, void or insignificant....” 20 Thus, use of the phrase “achieved in practice” by the best controlled similar source in Section 112(d)(2), particularly as it appears nowhere else in the Section, must be given full effect.
Turning to the final rule’s new source standards, they represent on their face, an amalgam of emission points from different facilities, and do not reflect the performance configuration of any source actually in existence in the PVC industry:

Table 1 : PVC MACT Sta n dards Applicable to New PVC

- Only Suspension Facilities

VCM TOHAP THC HCl Dioxin/furans
Limit (ppm) Facility Limit

(ppm) Facility Limit

(ppm) Facility Limit (ppm) Facility Limit

(ng/dscm) Facility
Stripped Resin 7.3 For-Bat 15 Wes-Gei -- -- -- -- -- -- Process Wastewater* 0.28 Oxy-Pas 0.018 Oxy-Dee -- -- -- -- -- -- Process Vents* 0.56 Shi-Fre 5.5 Shi-Fre 7.0 For-Del* 0.17 Shin-Add 0.038 For-Del* * These limits were not subcategorized by resin type and so apply to facilities that produce suspension, dispersion, and all other types of PVC resins.
As the Agency did not perform a beyond-the-floor analysis in setting the preceding standards, they presumably are intended to reflect emissions controls achieved in

17 42 U.S.C. § 7412(a)(3).

18 42 U.S.C. § 7412(a)(10).

19 NRDC v. EPA , 489 F.3d 1364, 1373 (D.C. Cir. 2007) (“EPA’s interpretation would make the words redundant and one of them ‘mere surplusage,’ which is inconsistent with a court’s duty to give meaning to each word used by Congress”).

20 Hibbs v. Winn , 542 U.S. 88, 101 (2004); Sprietsma v. Mercury Marine , 537 U.S. 51, 63 (2003).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 13 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com practice by the best-controlled similar source. The problem is that no such facility exists.
For example, and as we discussed in greater detail in Section II, a new PVC suspension facility would need to meet a wastewater TOHAP limit for wastewater based on sampling at the OxyVinyls Deer Park facility, which is an area source, and whose sampling represents only 44% of the facility’s product mix and less than 2% of the recipes the industry can make. Similarly, the VCM limit for wastewater is based on sampling at OxyVinyls’ Pasadena facility, which could never meet the current TOHAP limit given its use of methanol-bearing suspending agents. Moreover, it makes no logical sense that existing facilities have a wastewater non-VC TOHAP limit that is higher than the VCM limit, but the reverse somehow applies to new facilities.

A similar concern arises in the case of the new source stripped resin emissions standards for TOHAPs. The standards appear to be based on data sampled from the Westlake Geismar facility, but as Table 2 below indicates, that facility arguably has a low TOHAP concentration because it only produces four recipes annually, and only two of these, a general purpose and a low molecular weight, were produced during the 30- day resin sampling campaign. As such, it is not surprising that the Westlake facility detected only five analytes other than vinyl chloride in its stripped resin. In contrast, the OxyVinyls Deer Park facility, which produces nine different resins annually and sampled four of them, detected and was a top performer at controlling many more HAPs.

Table 2 also suggests three methods of identifying the top performers in the industry: (1) by the number of times in the top five; (2) by vinyl chloride ranking (lowest average vinyl chloride concentration); or (3) by non-VC TOHAP ranking (lowest average non-VC TOHAP concentration). Data for vinyl chloride is reported in bold. A comparison of these approaches, however, quickly indicates that there is no consistent performance level across these purportedly top performing facilities. For example, the best performing facility for TOHAPs is not in the top five for either vinyl chloride or for the number of individual analyte concentrations ranked in the top five.
It is worth harkening back to the D.C. Circuit opinion in Mossville Environmental Action Now v. EPA , in which the Agency argued that it was impossible to determine the best five sources because of the great variability in RVCM emissions, and the fact that this variability is a result of the type of resin being produced, not the technology or processes applied to control emission. 21 This conundrum applies to both vinyl chloride and TOHAP limits for stripped resin and process wastewater and presents a situation where comparisons between plants are impossible. The data clearly demonstrate that variations in resin and wastewater HAP profiles are not related solely to variations in technological performance, and that product mix and ingredient combinations play a significant role. As the Mossville court noted, EPA is authorized to reasonably estimate the performance of the best five performing sources, provided the Agency “has

21 Mossville Environmental Action Now v. EPA , 370 F.3d 1232, 1242 (D.C. Cir. 2004).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 14 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com supported its decision with record data that shows the connection between its MACT floor and the top performing plants.” 22

**Space left intentionally blank**

22 370 F.3d at 1242.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 15 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Table 2: Facility Resin Ranking by Analyte (excluding non-detects)Reporting Plant2,2,4-TrimethylpentaneAcetaldehydeAcetophenoneBenzeneBis(2-Ethylhexyl)PhthalateChloroformCumeneEthyl ChlorideEthylene DichlorideEthylidene DichlorideFormaldehydeHydroquinoneMethanolMethyl ChloridePentachlorophenolPhenolTolueneVinyl AcetateVinylidene ChlorideXylenes (Mixed Isomers)Vinyl ChlorideTOHAPLowest Rank++Times in Top 5++

Axiall* Aberdeen 10 6 11 13 9 8 6 11 8 6 12 11 6 0
Axiall* Plaquemine 11 3 10 12 13 10 7 12 13 7 7 12 3 1
Formosa Baton Rouge 4 5 2 5 4 8 6 9 3 3 4 1 5 2 8

Formosa Point Comfort 3 4 1 4 3 6 4 2 7 1 8 2 1 4 4 3 1 11
MexiChem** Henry 9 5 6 7 2 7 7 12 9 9 4 2 5 4 3 10 2 6
OxyVinyls Deer Park 3 1 1 3 3 2 3 5 4 1 2 1 3 1 3 3 3 2 2 1 17
OxyVinyls Pasadena 1 2 2 1 1 1 5 3 3 4 5 10 5 3 1 1 1 8 9 1 16
OxyVinyls Pedricktown 2 5 4 2 2 5 7 2 1 5 4 4 1 2 2 2 2 10 4 1 16

Shintech Addis 6 7 8 9 10 6 5 10 4 3 9 8 3 3
Shintech Plaquemine 6 7 8 9 10 2 5 10 4 3 5 7 2 4
Shintech Freeport 6 7 9 10 3 5 10 4 3 6 6 3 4
Westlake Calvert City 12 6 4 8 6 11 8 13 7 5 8 11 13 4 2
Westlake Geismar 1 1 5 2 6 13 1 1 4

++ Excludes vinyl chloride and TOHAP * Formerly Georgia Gulf ** Formerly PolyOneReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 16 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com D. The Data is the Data: Increased Limits on Reconsideration are Permissible and in this Case, Warranted At the July 23 meeting, EPA staff expressed concerns with promulgating a reconsidered final rule with raised emissions limits. The staff’s concerns appear to stem from petitioners’ arguments in ongoing litigation against the Agency that Section 112(d)(7) of the Clean Air Act prohibits EPA from setting revised emissions standards that are less stringent than existing limits: No emission standard or other requirement promulgated under this section shall be interpreted, construed or applied to diminish or replace the requirements of a more stringent emission limitation or other applicable requirement established pursuant to section 7411 of this title, part C or D of this subchapter, or other authority of this chapter or a standard issued under State authority

. It is important to note that the petitioners’ arguments arise in the context of a remand from the court and are inapplicable here. Indeed, we understand that petitioners have sought to carve out an exemption from their interpretation for changes to emissions limits that arise as a result of reconsideration. Notwithstanding such a carve out, and as the Agency argued before the court, 23 petitioners’ interpretation is unnatural and nonsensical because “it would prevent EPA from amending a section 112(d) standard that was technically deficient or incorrect.”
As the Working Group noted in its comments: Federal agencies also “have an obligation to deal with newly acquired evidence in some reasonable fashion,” and to reexamine the assumptions and approaches underlying a rulemaking if there is a change in “a significant factual predicate.” Such an obligation does not move solely in an ever-increasing spiral of stringency and burden. Otherwise, what would be the point of allowing industry to petition for reconsideration of a MACT? The argument is even stronger in the case of the PVC MACT, where both the Agency and industry identified significant errors and data gaps that arguably rendered the final rule limits invalid under the Act.
Given the scarcity of data behind some of the limits in the final PVC MACT rule, it should not be surprising that the emission limits may increase in some instances, and decrease in others, as a result of reconsideration. Nor, as the sections below will make clear, is the Working Group advocating any changes to the final rule limits that are not permissible under the statute or supported by adequate actual emission data. Where a demonstration has been made that an increase to the final rule emission limits is warranted, the Agency will violate the Act by failing to act accordingly.

23 Sierra Club v. E.P.A ., Case No. 10-1378, Resp. Proof Br. 17-24 (D.C. Cir. 2013) (oral arguments not yet scheduled).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 17 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com II. Reconsideration of Process Wastewater Limits
In its notice of proposed rulemaking, 24 EPA proposed a beyond-the-floor standard for total hazardous air pollutants (“HAP”) in wastewater. EPA proposed a 1,000 ppm by weight (“ppmw”) threshold for total organic HAP (including vinyl chloride), above which facilities would have been required to comply with the wastewater provisions of the HON. 25 EPA received no significant adverse comments regarding this beyond-the-floor proposal. Following the close of the comment period, however, EPA rejected this approach for the final rule. The Agency decided that all process wastewater streams “must meet a limit for total non-vinyl chloride organic HAP that is significantly lower than the proposed 1,000 ppmw threshold.” 26 Using the same calculation methodology for both vinyl chloride and non-vinyl chloride total organic HAPs (“non-VC TOHAPs”), the Agency finalized the following limits:

Table 3 : Final PVC MACT Wastewater Stripper Outlet Concentration Limits (in ppmw)

Pollutant Existing Major Sources New Major

Sources Existing Area

Sources New Area

Sources Vinyl Chloride 6.80 0.28 2.1 2.1 Non

-VC TOHAP 110 0.018 0.018 0.018
The Working Group’s petition for reconsideration did not object, in concept, to the new methodology, but noted that the Agency had not provided an opportunity to comment on the new approach. In addition, the Working Group’s analysis of the data used by EPA indicated that it was of insufficient quality and quantity to set wastewater concentration limits that are reflective of the emission limitations actually achieved by the five best performing facilities in the source category, as required by the Act.
On its face, the 0.018 ppmw non-VC TOHAP limit for existing area sources andall new sources is an immediate red flag that a problem exists with the data. The nonVC TOHAP limit for existing sources is one order of magnitude higher than the vinyl chloride limit, yet the non-VC TOHAP limits for new and area sources, which use the same stripping technology, is two orders of magnitude less than the vinyl chloride limit.
Working Group members reviewed the Microsoft Excel TM spreadsheet EPA used to calculate the wastewater limits, and determined that the 0.018 ppmw value used to set the new source wastewater non-VC TOHAP limit was invalid. Upon further review, it was determined that the data point represented a concentration value for acetaldehyde from a groundwater remediation stripper located next to the OxyVinyls Deer Park facility, rather than from the PVC wastewater stripper at the facility.
The other few data points EPA used to calculate the non-VC TOHAP limit also do not reflect the emission levels actually achieved by the industry. The Agency calculated

24 See National Emission Standards for Hazardous Air Pollutants for Polyvinyl Chloride and Copolymers Production ; Proposed Rule , 76 Fed. Reg. 29,528 (May 20, 2011).

25 76 Fed. Reg. 29,586.

26 Docket Document No. EPA-HQ-OAR-2002-0037-0185, at 13-69 to 13-70.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 18 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com MACT floors for non-VC TOHAP in wastewater using data from Sheet K-3-b of its Section 114 Survey. 27 The information requested by EPA, and provided by PVC facilities in most instances, was for 2008 data on hand. In this regard, it is important to remember that compliance with the Part 61 Vinyl Chloride NESHAP applicable to all PVC facilities did not require the collection of non-vinyl chloride data. Any non-vinyl chloride wastewater HAP data collected by PVC facilities would be limited to those few HAPs that may be of interest for a particular purpose, such as product quality control, meeting an existing permit limit, or to support a permit modification or renewal application.
In short, EPA had only six reported values (including the invalid 0.018 ppmw value for OxyVinyls Deer Park) for only three of the 30 HAPs the Agency’s non-VCTOHAP limit is intended to address. (MIBK reported for the Shintech facilities is a sitespecific HAP which is not on the list of 30 HAPs EPA identified in Table 10 of the final rule.) Critically, most of these values did not reflect actual samples of PVC facility wastewaters taken during actual operations. Nor was it clear that the facilities reporting represent the best performing facilities in the industry.
The Working Group is aware of at least one company that submitted wastewater sampling data in September 2010, covering a site-specific list of 20 HAPs for one of its facilities, but EPA did not use this data in calculating the floors. It is not clear whether the Agency overlooked the data, because the data set is not addressed in the background documents to the final rule. As the Working Group indicated in its petition for reconsideration, EPA should have accounted for other HAPs identified in the September 2010 data set, such as acetophenone, chloroethane, chloroform, and formaldehyde, when setting the final non-VC TOHAP limit. Thus, the information used by EPA to set the final process wastewater limits was insufficient and invalid for rulemaking purposes.
Ultimately, the Agency granted the petition for reconsideration on grounds that the public was not afforded a reasonable opportunity to comment on the emission limits in the final rule. To address the process wastewater data deficiency identified by industry, EPA, on November 8, 2012, issued its “Polyvinyl Chloride and Copolymers Process Wastewater Section 114 Sampling and Analysis, and Information Request” (hereinafter, “Wastewater 114 Request”) to eleven entities in the industry. Given the significant time and resources expended on the PVC MACT through 2012, Working Group members did not believe the adequacy of the wastewater sampling data should be left to chance. 28 Accordingly, Working Group members committed to submit sampling data that encompassed sixteen of the eighteen facilities in the PVC and copolymers major and area source categories.

27 Docket Document No. EPA-HQ-OAR-2002-0037-0193, at 38, 41-42.

28 Letter from Richard Krock, The Vinyl Institute, to Andrea Siefers, EPA, RE Polyvinyl Chloride and Copolymers Process Wastewater Section 114 Sampling and Analysis, and Information Request (November 26, 2012).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 19 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Sampling began on or before January 7, 2013, and results were submitted to EPA by the May 1, 2013 deadline set by the Wastewater 114 Request. Upon careful review of the new data, the Working Group believes that the only viable approach—one that reflects the product variability of the PVC industry and the actual emissions control performance of the best performers in the industry—is to set a separate limit for vinyl chloride and TOHAPs. The accompanying database is enclosed as Attachment II and was submitted to the Agency on electronic media via separate cover.
The separate limit for vinyl chloride should be based on the 12-month 2008 sampling data set. The non-VC TOHAP limit should be set at 1,000 ppmw, with provisions for addressing TOHAP concentrations above 1,000 ppmw.
A. Product Variability Has Significant Impacts on Wastewater HAP Profiles The Working Group considered whether further subcategorization by PVC resin type is feasible or warranted. All PVC production facilities (other than Dow Midland) use steam stripping to control residual HAPs before exposing process wastewater streams to atmosphere. Nevertheless, the wastewater profile will vary depending on the type of resin produced. As a practical matter, however, there is a wide divergence in facility configurations, which makes subcategorization by resin type difficult. Some facilities run their wastewater strippers continuously, whereas others run their strippers as a batch operation. Some facilities have only one stripper per PVCPU, whereas others route wastewater from multiple PVCPUs to a single stripper. Still other facilities produce only one type of resin ( e.g. , suspension, dispersion, etc.), whereas others produce multiple resin types, the combined wastewaters of which are comingled and routed to a single stripper. Table 4 illustrates the diversity of facility configurations. The Dow Midland facility is not included because it does not use a wastewater stripper.

Table 4: PVC Industry Wastewater Stripper Configurations

Company & Facility # of Resins Produced Simultaneously # of WW

Strippers Resin Type # of Resin Grades

Axiall* Aberdeen 4 1 Suspension 7 Axiall * Plaquemine 5 1 Suspension 17 Formosa Baton Rouge 3 1 Suspension 15 Formosa Delaware 6 2 Copolymer, Emulsion 14 Formosa Point Comfort 3 1 Suspension 15
Formosa SPVC 6 1 Suspension, Blending, Dispersion, & Copolymer 20 OxyVinyls Deer Park 2 1 Suspension 9 OxyVinyls Pasadena 7 1 Suspension 6 OxyVinyls Pedricktown 2 0*** Suspension 10 MexiChem** Henry 5 1 Suspension, Blending, & Dispersion 12 MexiChem** Pedricktown 2 1 Suspension***/Dispersion 11 Shintech Addis 2 1 Suspension 12 Shintech Freeport 9 3 Suspension 12 Shintech Plaquemine 2 1 Suspension 12 Westlake Calvert City 1 1 Suspension 1 Westlake Geismar 2 1 Suspension 4 Totals 61 18 177 * Formerly Georgia Gulf ** Formerly PolyOne *** OxyVinyls wastewater processed by MexiChem Pedricktown FacilityReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 20 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com As we discuss further below, it is the wide variability in ingredients between different grades within the same resin types that drives the variability in wastewater HAP profiles. The Working Group is unaware of any non-technology factors besides product recipes that affect HAP wastewater concentrations and could have a role in setting concentration limits. Indeed, the data indicates that, industry-wide, control technology performs similarly, and the only discernible difference between the best and worst performers is the set of recipe ingredient requirements necessitated by customer demand. To test this analysis, the Working Group reviewed the 30-day sampling data and developed an average wastewater concentration for each HAP, at each facility. Next, we compared the performance of each facility by HAP to identify the best performing facilities per HAP.

Table 5 below summarizes the result of this comparison. The numbers reported in each grid reflect the individual facility ranking for a particular analyte. Data for vinyl chloride is reported in bold. Numbers highlighted in green reflect the top five performing facilities for that particular analyte. As Table 5 indicates, fourteen of the fifteen facilities were a top-five performer for at least one analyte; twelve of the fifteen facilities were a top-five performer for at least five analytes; and seven of the fifteen facilities were the best performer for at least one analyte.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 21 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Table 5: Facility Wastewater Ranking by Analyte (including non-detects)Facility1,1,2,2-tetrachloroethane1,1,2-Trichloroethane1,3-butadiene2,2,4-trimethylpentane2,4-dinitrophenol4-Methyl 2-pentanone (MIBK)AcetaldehydeAcetophenoneBenzeneBis(2-ethylhexyl) phthalate(DEHP)ChlorobenzeneChloroformChloropreneCumeneEthyl chloride (Chloroethane)EthylbenzeneEthylene dichloride (1,2-Dichloroethane)Ethylene glycolEthylidene dichloride (1,1-Dichloroethane)FormaldehydeHydroquinoneMethanolMethyl chloride(Chloromethane)Methyl chloroform (1,1,1-Trichloroethane)Methylene chloriden-HexanePhenolTolueneVinyl acetateVinyl bromideVinyl chlorideVinylidene chloride (1,1-Dichloroethylene)Xylenes (isomers andmixtures)TOHAPBest RankTimes in Top 5

Axiall* Aberdeen 12 10 12 13 7 12 15 9 12 8 12 13 9 9 10 11 7 13 14 11 14 13 13 13 14 13 9 10 11 12 8 14 7 0 Axiall * Plaquemine 4 2 6 11 6 9 11 3 11 4 6 9 8 12 3 4 2 6 15 15 13 6 7 10 12 9 4 3 12 3 4 11 2 11 Formosa Delaware 15 15 15 15 15 14 3 15 6 15 15 14 15 13 15 15 12 15 12 14 11 12 15 15 15 14 15 14 13 9 15 15 13 3 1 Formosa Baton Rouge 14 14 11 14 13 5 14 14 15 14 14 15 14 5 14 3 5 14 3 13 4 5 14 14 13 15 14 11 12 3 14 14 4 3 9 Formosa SPVC 13 11 10 12 11 15 5 12 10 11 13 11 11 11 12 5 6 12 2 5 1 8 12 12 9 7 12 15 9 13 13 13 12 1 5 Formosa Point Comfort 2 3 1 1 10 7 12 2 9 2 2 2 3 8 2 10 4 2 1 10 12 11 2 5 1 11 2 4 1 8 2 2 10 1 21 OxyVinyls Deer Park 7 7 5 3 3 2 8 6 7 4 7 7 5 5 7 7 7 13 7 8 3 3 7 6 3 4 2 7 7 6 7 6 7 1 1 13 OxyVinyls Pasadena 6 5 3 4 12 1 11 13 5 14 5 3 4 10 3 5 2 13 4 4 12 15 2 3 4 2 10 6 5 2 5 4 6 15 1 21 MexiChem** Henry 11 13 14 9 1 1 4 13 1 13 11 8 13 15 13 14 9 9 7 1 2 14 11 9 10 1 13 13 11 15 11 10 2 1 8 MexiChem** Pedricktown 10 12 13 8 14 13 7 11 3 12 10 6 12 14 11 6 13 8 6 8 5 15 10 8 8 12 11 12 10 14 10 9 6 3 2 Shintech Addis 9 9 9 7 5 5 3 8 10 5 10 9 12 7 6 9 12 10 11 10 2 8 9 9 7 7 4 10 9 8 6 9 12 7 2 6 Shintech Freeport 5 5 3 2 8 3 6 9 5 7 5 3 3 4 2 5 8 8 4 11 4 7 3 3 2 2 5 5 5 2 2 4 5 5 2 26 Shintech Plaquemine 8 8 8 6 9 4 10 10 8 13 9 8 10 6 4 8 9 10 10 5 7 9 4 8 6 5 6 8 8 7 4 7 11 9 4 6 Westlake Calvert City 1 1 2 5 2 2 1 1 2 1 1 1 1 1 1 1 3 1 9 6 6 1 1 1 6 3 1 1 2 1 1 1 3 1 29 Westlake Geismar 3 4 7 10 4 4 2 4 8 3 5 7 2 10 4 13 1 3 13 9 10 10 5 11 11 8 3 2 2 10 8 3 8 1 17 * Formerly Georgia Gulf ** Formerly PolyOneReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 22 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com For example, the best performing facility for TOHAPs is not in the top five for either vinyl chloride or the number of top-five rankings. Indeed, only the Westlake Calvert City and Shintech Freeport facilities were consistently top-five performers under all three approaches, but these facilities produced a relatively limited slate of products during the 30-day sampling period; consequently, their data reflect very little product variability. For example, Westlake Calvert City produces only one resin recipe.
Thus, as the Working Group has consistently maintained, the attempted identification of top performing facilities can be misleading because such an analysis overlooks the variability in HAP profiles, which is the result of the resin type or grade being produced, rather than the control technology or other processes used to control emissions. Such variability is readily apparent when examining individual analytes at a single facility. For example, at the OxyVinyls Deer Park facility, which can produce onlytwo resin products at one time, acetophenone is a decomposition product of a peroxidebased initiator used in one of the recipes. As the chart below indicates, the presence of acetophenone generally corresponds to the facility’s product mix in the early part of the Section 114 sampling campaign, and then drops off precipitously after a recipe change.

Figure 1: OxyVinyls Deer Park 30-Day Acetophenone Please note that as wastewater samples were collected for all facilities at the discharge of the stripper treatment equipment, recipe changes may not be readily apparent in all circumstances because of the commingling of wastewater in stripper feed tanks, or where wastewaters from multiple production lines converge to a single stripper.
The Agency also must consider natural variability in the operation of control equipment. Figure 2 summarizes the vinyl chloride concentrations in wastewater from the steam stripper at OxyVinyls Deer Park facility. Two spikes in the vinyl chloride concentration were reported during the 30-day data collection period held in early 2013. These spikes in vinyl chloride concentration occur throughout the data submitted to the Agency, including the one-year data set for 2008, which the Agency used to calculate the vinyl chloride limits in the final PVC MACT rule.

0 500 1000 1500 2000 2500 3000 3500 4000

1 2 3 4 5 6 7 8 9 101112131415161718192021222324252627282930313233ppb - ug/L

Sample DayReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 23 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Figure 2: OxyVinyls Deer Park 30-Day Vinyl Chloride
It is the opinion of the Working Group that these fluctuations do not reflect any type of upset condition, but rather occur within a range of variability that should be considered normal operation. To test this view, engineers at the OxyVinyls Deer Park facility added a sampling port to the wastewater stripper column feed and collected matched influent and effluent data for vinyl chloride during the period of July 11-13, 2013. The results of this analysis are reported in Table 6 below.

Table 6: OxyVinyls Deer Park PVC

– Wastewater Stripper VCM In and Out Date July 11, 2013 July 12, 2013 July 13, 2013 Units mg/L (ppm) mg/L (ppm) mg/L (ppm) Column Influent 1520 1800 1320 Column Effluent 2.04 0.289 0.356 Sample Type Grab Grab Grab

NOTE: Samples taken with cooling coils in place.

As the grab sample results indicate, vinyl chloride was well removed by the wastewater stripper during all three days. No upset condition or other reason could be found for the spike that occurred on July 11 (in bold), and this is considered normal operation. Vinyl chloride wastewater concentrations from the OxyVinyls Pasadena plant, which is one of the top five performing facilities for vinyl chloride, also reported spikes under normal operating conditions during the 30-day sampling period in early 2013 as shown in Figure 3

.

0 100 200 300 400 500 600 700 800 900 1000

1 2 3 4 5 6 7 8 9 101112131415161718192021222324252627282930313233ppb ug/L

Sample DayReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 24 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Figure 3: OxyVinyls Pasadena 30-Day Vinyl Chloride
Accordingly, the Working Group submits that because continuous compliance is determined by a single grab sample per month pursuant to the PVC MACT final rule, the actual limits should take into account the obvious fluctuations in wastewater stripper effluent that take place on a random, but regular, basis, while still exhibiting very good performance overall, as discussed in the next section.
B. Alternative Compliance Demonstration for VCM and TOHAP in Wastewater The final PVC MACT rule indicates that for VCM and TOHAP in wastewater, the numerical limits that EPA statistically derived from admittedly limited industry data are to be met continuously and that one grab sample per month must be taken for comparison with the derived limits to demonstrate compliance. Essentially, whenever a single instantaneous grab sample is taken, at any time, it can be used to determine compliance or noncompliance. There are several difficulties and inconsistencies in using this approach for wastewater samples.
First and foremost, one of the significant factors that can determine compliance or noncompliance is the inherent variability of HAPs and their concentrations in the PVC manufacturing process, as described elsewhere in this letter. If compliance is required 100% of the time, as in the current MACT rule, then instantaneous peaks in the concentrations of HAPs during normal operations will be a significant factor in the compliance determination. Limited data sets used for development of numerical limits are likely to underestimate the frequency and magnitude of these commonly occurring instantaneous peak values. In addition, undetected errors in sampling and lab analysis also can inappropriately lead to apparent non-compliant event reporting.

Second, the limited data sets that must be used to set numerical MACT limits usually need to be averaged in some way before statistical methods are used to

0 100 200 300 400 500 600 700 800 900 1,000

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35ppb ug/L

Sample DayReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 25 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com calculate limits and predicted variability. This is certainly true for the calculations used to develop both the VCM and TOHAP emission limits of the final PVC MACT rule. For VCM in wastewater, EPA utilized a 2008 industry data set of wastewater stripper effluent results. Since the total number of samples for VCM at each of the industry wastewater strippers varied from once a month (12 grab samples) to several times a day (greater than a thousand grab samples), normalization via calculation of monthly averages for each PVC facility was utilized so that the weighting of all facilities was equalized. This resulted in 12 values for each of the top five facilities, or a data set consisting of 60 monthly averages. Statistical analyses were then performed to determine the upper predictive limit (“UPL”) for the monthly averaged data. The problem is that a significant portion of the grab sample variability was removed in the averaging process before the statistical procedure was used to determine the UPL. All normal operation VCM spikes (grab samples) were essentially removed, leading to even more of a reduction in the variability than that done by averaging alone. As a result, such numerical limits, when applied as instantaneous maximums for compliance purposes, will seriously impact any PVC facility’s ability to demonstrate continuous compliance. Indeed, measuring compliance with a limit that is based on a 30-day average by use of a single grab sample has the effect of imposing a MACT limit that does not reflect what is actually achieved by the five best performing facilities under normal operations.
Third, since every grab sample analyzed is an opportunity for an individual limit violation, there is a disincentive to take any additional samples above the monthly frequency specified in the final rule for both vinyl chloride and TOHAP. For instance, it is likely that vinyl chloride analyses on wastewater stripper effluent would be desirable on a more frequent basis than monthly, as part of the process control program, to ensure normal operation of the stripper. If every such sample is another violation possibility, it is a disincentive to take such measurements for any such purpose. There is not a direct process control reason to sample more than once a month for TOHAP in wastewater as required in the final rule. Additional TOHAP samples, however, could be useful as an aid in process control of any downstream activated sludge treatment systems, or to modify daily product mix characteristics to assure continuous compliance. If such samples were taken under the current PVC MACT rule, they would present another opportunity for a MACT limit violation to occur, and the disincentive would still be present.

1. Proposed Solution: EPA Should Allow Monthly Compliance Averaging EPA’s Clean Water Act NPDES wastewater permitting program has addressed the difficulties of demonstrating continuous compliance with numerical wastewater limitations. NPDES permits only rarely specify grab samples for numerical effluent limitation compliance. Rather, most NPDES permits require demonstration of compliance with monthly average limitations via limited sampling frequency, e.g., once a month, or once/twice a week. The permits also include in their standard conditions, however, the following reporting clause:Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 26 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com If the permittee monitors any pollutant more frequently than required by the permit using test procedures approved under 40 CFR 136, or another method required by an industry-specific waste stream under 40 CFR subchapters N or O, the results of such monitoring shall be included in the calculation and reporting of the data submitted in the DMR or sludge reporting form specified by the Director. 29

This standard condition, found in all NPDES permits, requires that additional sample results be used in reporting, and for a monthly average permit limitation, the data must be used in computing the monthly average. Thus, a permittee can take additional samples in any given calendar month. If an initial compliance sample result reports a wastewater concentration above the numerical permit limitation for a parameter, additional samples may be taken to determine if the initial exceedance was truly representative of performance, or if it was an anomalous result that, nevertheless, must be included in the monthly compliance average. If the permit exceedance was indeed anomalous, then the use of the additional sample in the monthly average calculation could result in demonstrated compliance for that month. If there is a performance problem, then more sampling will not bring down the average for the month and a monthly average violation will occur.
The Working Group requests that EPA consider adopting a monthly compliance averaging approach that is similar, if not identical, to the approach used under the NPDES program for all wastewater limits under the PVC MACT. This would involve adding a provision that requires that any additional samples taken during the month be used in the calculation of a monthly average concentration for compliance purposes. The minimum sampling frequency would remain as one monthly grab sample.

2. Also Apply Compliance Averaging to Wastewater Stream Treatment Determinations The Agency also should allow PVC facilities to average samples when making initial, and subsequent annual determinations regarding whether untreated process wastewater streams need to be treated. These determinations are required by Sections 63.11970 and 63.11975, respectively, but these sections do not explicitly state how many samples can or must be analyzed. As discussed in Section II.B.1, EPA should allow facilities to collect and average one or more samples over a one-month or longer period in order to ensure that the initial and annual determinations are based on sampling that is representative of a facility’s product mix.
C. The Wastewater Limits Must Allow for the Production of Copolymers and the Use of Suspending Agents and Other Ingredients that Contain HAPs
Table 5 also validates the Agency’s decision, in both the proposed and final PVC MACT, to set separate limits for vinyl chloride and for non-VC TOHAP. According to EPA:

29 40 C.F.R. § 122.41(l)(4)(ii).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 27 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com A total HAP limit is appropriate because emissions from PVC facilities are comprised of mixtures of these HAP, and the control technologies used to control total HAP such as condensers and thermal oxidizers, achieve control of the individual HAP. 30 The Working Group supports this approach. As we have consistently noted, it is important to understand the impact of the various recipes on process and waste streams. As we noted in Section II.A, some facilities that produce different types of resin ( e.g. , suspension, dispersion, etc.) and even both copolymers and homopolymers, combine and commingle their wastewater en route to a single stripper. Vinyl chloride is always present, although in varying quantities, but the other ingredients will vary depending on the recipe and resin characteristics sought.
In light of these facts, a TOHAP limit is the only workable solution. Nevertheless, the Agency’s methodology for setting a TOHAP limit was fundamentally flawed, as it foreclosed a significant segment of industry products. As Congress noted in Section 112(d)(2) of the Act: None of the [pollution control] measures described in subparagraphs (A) through (D) shall, consistent with the provisions of section 7414(c) of this title, in any way compromise any United States patent or United States trademark right, or any confidential business information, or any trade secret or any other intellectual property right. The preceding language demonstrates Congress’ intent to ensure that MACT standards do not harm the intellectual property of regulated entities. Trade secret and intellectual property considerations are at the heart of recipe considerations in the industry.

1. 110 ppm TOHAP Limit Would Foreclose VAM Copolymers The Formosa facility in Delaware and the Formosa Specialty Polyvinyl Chloride (“SPVC”) plant in Point Comfort, Texas both produce PVC copolymer resins using vinyl acetate as a co-monomer. The Delaware facility is capable of producing a total of fourteen resin recipes at a rate of one to three recipes a day, across two distinct process lines, each with its own wastewater stripper system. The Formosa SPVC plant can make fifteen different resin recipes at a rate of one to three recipes per day across two distinct process lines. Wastewater from both lines are routed to a single stripper.

30 76 Fed. Reg. 29,540.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 28 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Figure 4: Formosa SPVC 30-Day Vinyl Acetate

As Figure 4 illustrates, the Formosa SPVC facility produced multiple resins during its 30-day sampling period. Non-VC TOHAP generally was well below the 110 ppm limit on most days. On some days, however, the SPVC facility used vinyl acetate as the secondary co-monomer to produce its PVC copolymer. Although the Formosa Delaware facility produced copolymer recipes on fewer days, the use of vinyl acetate is quite obvious from the data summarized in Figure 5

.
As Figures 4 and 5 illustrate, the high vinyl acetate levels mean that the Formosa facilities could not comply with the 110 ppm non-VC TOHAP limit on the days they produced their copolymer resins. It is important to note that even with a 1,000 ppm limit, the facility would be in non-compliance at least three times during the sampling period. Similar concerns arise in the use of certain ingredients critical to the production of homopolymers.

0.0 500.0 1,000.0 1,500.0 2,000.0 2,500.0 3,000.0 3,500.0 4,000.0 4,500.0 5,000.01/21/41/61/81/101/121/141/161/181/201/221/241/261/281/302/12/32/5Vinyl Acetate, ppm

2013 Sample Date 110 ppm TOHAP HON 1,000 ppm TOHAP LimitReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 29 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Figure 5: Formosa Delware 30-Day Vinyl Acetate
2. 110 ppm Limit Would Foreclose the Use of Several Critical Ingredients As the Working Group has previously advised, vinyl chloride has low water solubility (2.7 g/L), yet a relatively high Henry’s Law coefficient (2.65 X 10 -2 atmm 3/mol), 31 which reflects a high level of volatility. Thus, steam in proper proportions and in a properly designed and operated wastewater stripper is the most practical and efficient design for removing vinyl chloride and other relatively insoluble organics in wastewater. There are several soluble HAPs, such as acetaldehyde, ethylene glycol, methanol, and vinyl acetate, which may not be fully removed by a wastewater stripper, but have a low HAP emission rate from the wastewater stream in any case.

As impurities, these substances generally are present in small concentrations that are relatively well managed by the wastewater stripper, as the 30-day data set indicates. The water-soluble HAPs present as critical ingredients or ingredient components typically are present at higher concentrations that are not fully treated by wastewater strippers. Methanol provides an excellent example of why a higher TOHAP limit is needed to allow the continued use of these critical ingredients.
Primary suspending agents (“SAs”) are used to control monomer droplet formation, which in turn affects the particle size and shape, porosity, bulk density, finished product rheology, and ultimately, residual vinyl chloride monomer (“RVCM”) in stripped resin. Primary SAs (normally solid granular products) are used in all grades of PVC resin recipes and typically contain < 0.5% methanol, which is a residual solvent from the manufacture of SAs. According to one manufacturer of suspending agents,

31 EPA, Air Emissions Models for Waste and Wastewater, Appendix C, EPA-453/R-94-080A.

0.0 2,000.0 4,000.0 6,000.0 8,000.0 10,000.0 12,000.01/71/101/131/161/191/221/251/281/312/32/62/92/122/152/192/222/263/13/53/83/113/163/194/1Vinyl Acetate, ppm

2013 Sample Date 110 ppm TOHAP Limit HON 1,000 ppm TOHAP LimitReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 30 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com complete removal of the residual methanol is impractical, as it causes degradation of the suspending agent.
Secondary SAs control the agglomeration of polymerized particles in order to meet specifications relating to particle size distribution, porosity, residual vinyl chloride, bulk density, slurry stability, and reactor build-up. Many secondary SAs (normally liquid products) typically contain 4 – 5% methanol, which acts as a solvent for the SA in its liquid vehicle. Although SAs are available with or without methanol, the selection of such agents depends on several intellectual property considerations, including critical factors unique to each producer, its facilities, and its customer base.
For example, Formosa’s Point Comfort and Baton Rouge facilities both produced a pipe grade resin (among others) during the 30-day wastewater sampling campaign. Both facilities have an “Authorized Registered Formulation” with NSF International for use with certain products. NSF is a widely respected and recognized global third party product specification certification provider. A certification from NSF specifies the specific materials/ingredients and quantities authorized for use in a NSF certified product. The Point Comfort facility, however, uses several raw materials and has certain site-specific operational procedures that are different than the Baton Rouge facility, for a variety of reasons, including:

 Differences in equipment, including reactor geometry and agitation. Even within a single facility, the configuration of PVC reactors can vary widely depending on the manufacturer’s intellectual property matrix involving particular resin recipes, equipment configurations, licensing agreements, etc.

 Customer requirements. These requirements often are identified in a “Customer Quality Requirement Form,” which typically specifies the use of different ingredients and/or different chemical suppliers.

In addition to Formosa Point Comfort, four other facilities used methanol-based secondary SAs during the 30-day sampling period: Axiall Aberdeen, Axiall Plaquemine, OxyVinyls Pasadena, and Westlake Geismar. Depending on the facility product mix, methanol was usually the main constituent of the TOHAP value. As we noted earlier, it is practical to use steam in proper proportions and in a properly designed and operated stripper to remove vinyl chloride and other relatively insoluble organics. In contrast, methanol has high water solubility (fully miscible with water in all proportions) and a relatively low Henry’s Law coefficient (5.2 X 10 -6 atm-m 3/mol), 32 and as such, steamstripping is not an optimal mode of controlling for methanol. In light of these wellrecognized scientific principles, the Working Group submits that any remaining concentration of methanol in wastewater is not an indication of stripping performance relative to other facilities, but rather is produced as an artifact of the recipe.
OxyVinyls Pasadena is an interesting case in point. As Table 5 indicates, OxyVinyls Pasadena is one of the top five performers for VC and is a top performer in

32 Id.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 31 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com controlling the largest number of individual analytes. Yet it has the highest methanol average of any facility, which in turn drives its low ranking for TOHAP. A closer review of the data, as Figure 6 ilustrates, reveals that the facility used methanol-based suspending agents throughout the 30-day wastewater sampling period, and residual methanol from these ingredients was responsible for 97% of the average TOHAP concentration at the facility. Given the facility’s control of other wastewater HAPs, the high methanol values are clearly an artifact of the recipes, rather than poor wastewater stripper control.

Figure 6: OxyVinyls Pasadena 30-Day Methanol
The Working Group submits that these HAP profiles, including spikes and troughs, are clear indications of recipe variability, although there may be some delay in correlating readings to particular resin production days at those facilities where wastewater either is batched or routed from multiple production lines to a single wastewater stripper.
The Working Group initially assumed that recipes using suspending agents that contain methanol were limited to certain resin types, and that product variability could be addressed through some form of subcategorization. As Table 7 indicates, the use of suspending agents containing methanol does seem to be limited to suspension resins, at this time. The broad array of end-use products that are affected suggests, however, that a wide variety of resin recipes cannot be produced under the current TOHAP limit.

Table 7: Methanol Concentration Across Product Types
Facility Resin

Type Conc. Range

(ppmw) Low Conc. Resin Product High Conc. Resin Product

Axiall** Aberdeen Suspension 0.2* – 2300 Pipe, Siding, Fence, Profiles, Molding Pipe, Siding, Fence, Profiles, Molding, Bottles, Sheet, Flexible

Axiall** Plaquemine Suspension 0.2* – 780 Pipe, Siding, Fence, Profiles, High Flow Molding, Medical, Wire and Cable Pipe, Siding, Fence, Profiles, Bottles, Film, Sheet, Flexible

Formosa Point Comfort Suspension 105 – 204 Pipe, Conduit Bottles, Sheet OxyVinyls Pasadena Suspension 519 – 1060 Pipe, Film, Extrusion, C alendaring, Pipe, Film, Sheet, Calendar,

0.0 200.0 400.0 600.0 800.0 1,000.0 1,200.0Methanol, ppm

110 ppm TOHAP Limit HON 1,000 ppm TOHAP LimitReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 32 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Table 7: Methanol Concentration Across Product Types
Facility Resin

Type Conc. Range

(ppmw) Low Conc. Resin Product High Conc. Resin Product

Sheet, Extrusion Injection Mold Westlake Geismar Suspension 0.2* – 247 Pipe, Rigid Molding Pipe, Fittings * Denotes non-detect reported as detection limit ** Formerly Georgia Gulf
Thus, two options present themselves. EPA can either provide a separate limit for intentional uses of secondary suspending agents containing high methanol amounts (as opposed to methanol that is present as an impurity in primary suspending agents used in other recipes), or adopt a 1,000 ppmw TOHAP limit similar to the original proposed rule.
The Working Group first considered an intentional use scenario, whereby EPAwould in addition to a vinyl chloride limit, set a methanol limit and a non-VC, nonmethanol TOHAP limit for facilities that use methanol-based ingredients. Facilities that do not use such ingredients would be subject to the vinyl chloride limit and a non-VC TOHAP limit that is calculated by excluding the “methanol users” from the non-VC TOHAP data set. The resultant non-VC TOHAP limit would include methanol present as an impurity. This approach could be justified because methanol concentrations in facilities where the substance is present solely as an impurity are so low, that a methanol limit applicable to all facilities would not provide any relief from the product ban dilemma.
The methanol limit would be developed using the 30-day sampling data from those five facilities that use methanol-based ingredients in their PVC resin recipes. Methanol users also would be subject to a non-VC, non-methanol TOHAP limit as follows:

Table 8: TOHAP and Methanol Limits Based on Ingredient Use

HAP Limit for Facilities Using MethanolBased Ingredients (ppmw) Limit for Facilities Not Using Methanol-Based Ingredients (ppmw)

Non-VC TOHAP

-- 140 Non-VC, Non-Methanol TOHAP 96

-- Methanol 500

-- Unlike a broad 1,000 ppm limit, this approach narrowly targets only those facilities that need to use methanol-containing ingredients. There are significant problems with this approach, however. First, the methanol performance achieved by some of these five facilities varied significantly. For example, Axiall Aberdeen recorded both the highest methanol concentration (2300 ppm) and the lowest methanol concentration (0.2 ppm). (The lower methanol concentrations are related to the production of flexible products and certain low RVCM pipe grades.) As a result, the calculated methanol limit after factoring a 99% UPL and monthly compliance sampling (m=1) was 15,000 ppm. Such a high limit suggested that the UPL was not an appropriate statistical approximation of the average performance of these facilities.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 33 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com The Working Group also considered setting the methanol limit at the arithmetic mean of 340 ppm. This value, however, also poses some difficulties as only one facility used methanol-based ingredients during the entire 30-day sampling period. Thus, the average performance for methanol use is inherently depressed and does not reflect the performance these facilities actually achieved. Indeed, Figure 7 indicates that three of these best performers for intentional use would be out of compliance with a 340 ppm limit on a significant number of days.
It is also worth noting that the two facilities operating regularly below 340 ppm during the 30-day sample period, Formosa Point Comfort and Westlake Geismar, each produced four recipes during the sampling period, which together is less than five percent of the total recipes produced by the PVC industry in a calendar year. In addition, the data indicates that on certain days, two of the other facilities were among the best performers, depending on the recipe being produced that day. Thus, the Working Group concluded that significant product variability may have been overlooked. Given this consideration, we believe that a methanol limit of between 500 ppm and 800 ppm would be reasonable and is supported by the data.

Figure 7: Methanol Performance of Facilities Using Methanol-Based Ingredients
There are significant, practical concerns with a methanol limit based on intentional use, however. First, such approach would require facilities to declare their intent to use methanol, and it is not clear that such communications with the Agency or state permitting officials can occur in sufficient time to meet typical business

0 500 1000 1500 2000 2500

0 5 10 15 20 25 30Methanol (ppm) 

## Methanol Using Facilities vs Calculated

Methanol Limit

Axiall ABD MS
Axiall PLQ LA

Formosa TX Oxy Pasadena, TX

Westlake LA

800 PPM

500 PPM
Average 99% UPL is 15,000Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 34 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com exigencies. 33 Second, these notifications would need to be confidential so as to protect critical company interests in market position, product mix, etc. It is not clear that such information could be protected, as it arguably helps to determine the compliance status of facility emissions. Ultimately, this is a much more difficult standard to administer because it involves additional limits and subcategories, and requires additional documentation by both the affected source and the Agency.
More importantly, the creation of a separate methanol limit fails to address the de facto ban on copolymer resins discussed in Section II.C.1. Accordingly, the Working Group submits that the Agency should instead consider an approach similar to the Agency’s original proposal and adopt a 1,000 ppmw non-VC TOHAP limit for both existing and new sources . As we discussed in Section II.B, such a limit would include a monthly compliance averaging approach similar to the approach used by the NPDES program.
The EPA staff expressed some reservations about this approach during our July 23 meeting. In response, we would direct the staff to the D.C. Circuit opinion in Mossville Environmental Action Now v. EPA , in which the Agency argued that it was impossible to determine the best five sources because of the great variability in RVCM emissions, and the fact that this variability is a result of the type of resin being produced, not the technology or processes applied to control emission. 34 The Working Group submits that the wastewater limits present a similar situation where comparisons between plants are impossible, and the data clearly demonstrate that variations in wastewater HAP profiles are not related to variations in technological performance, but rather to product recipes and ingredient combinations.

As the Mossville court noted, EPA is authorized to reasonably estimate the performance of the best five performing sources, provided the Agency “has supported its decision with record data that shows the connection between its MACT floor and the top performing plants.” 35 Arguably, setting a 1,000 ppmw limit would present some difficulty as the best performing facilities for TOHAPs never produced resins with methanol-bearing ingredients. It is important to note, however, that the facilities with the lowest reported methanol concentrations of any facility on a particular day, Axiall Aberdeen, Axiall Plaquemine, and Formosa Delaware, also produced resins on other days using methanol-bearing ingredients, and arguably are the top-performing plants with respect to methanol on those days.

The question of which plants are the top performers is further confused, because the wastewater sampling campaign covered only about 60% of the product mix produced annually by the industry. As Table 9 below indicates, the top performers

33 Arguably, the Agency requires the facility to record such use, and report it to EPA or the states as part of the facility’s quarterly reports. The facility would be responsible for demonstrating to the agencies, upon request, that it is using methanol-containing ingredients to qualify for use of the higher limit.

34 Mossville Environmental Action Now v. EPA , 370 F.3d 1232 (D.C. Cir. 2004).

35 370 F.3d at 1242.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 35 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com during the 30-day sampling campaign, under any of the three best performance scenarios discussed above, i.e., TOHAPs, VC, or number of top five individual analytes, account for less than 30% of the industry’s product variety in a calendar year. Indeed, taken together, during the 30-day sampling period, these nine facilities tested only 29.9% of the resins produced by the U.S. PVC industry in a given year.

Table 9 : Comparison of Best Performance Rankings

Company & Facility # of Top 5 Individual Analytes VC Rank TOHAPs Rank % Industry

Product Mix Sampled Formosa Baton Rouge 8 3 4 4.5% Formosa Point Comfort 3 8 10 2.8% OxyVinyls Deer Park 6 7 1 2.3% OxyVinyls Pasadena 4 5 15 2.8% MexiChem* Henry 9 15 2 6.8% Shintech Freeport 2 2 5 6.8% Shintech Plaquemine 10 4 9 1.1% Westlake Calvert City 1 1 3 0.6% Westlake Geismar 5 10 8 2.3% Total 29.9% * Formerly PolyOne
Based on the foregoing, it can hardly be said that any single source, or any five sources, are truly the best performers or reflect the average emissions control limitations achieved by these sources for purposes of setting the wastewater HAP limit. Moreover, as Figure 8 indicates, the data in the record illustrate the connections between a 1,000 ppm TOHAP MACT floor and the best performing plants.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 36 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Figure 8: PVC Producers Demonstrating Variability in Methanol
3. The Reconsidered Rule Should Allow Flexibility for Reducing the Emission of Soluble HAPs Including Methanol As discussed above, the Agency should revert to the 1,000 ppm TOHAP limit for wastewater initially proposed by the Agency. The proposed rule also incorporated by reference sections of the HON that provide the control measures required for wastewater that would have to be treated to reduce the concentration of TOHAP to less than 1,000 ppm, specifically 40 C.F.R. §§ 63.132 to 63.138, 40 C.F.R. § 63.143, and 40 C.F.R. §§ 146 to 147. 36 The Working Group submits that these requirements are unnecessarily burdensome and onerous, as they will require facilities that can meet a 1,000 ppm TOHAP limit most of the time to take expensive measures to address the rare occasions when TOHAP concentrations may approach (or have the potential to exceed) 1,000 ppm due to process variability or product mix.

Fundamentally, the wastewater concentration limits serve to control emissions to the atmosphere downstream of the wastewater stripper. 37 The sections of the HON cited above do not impose additional control technology for TOHAPs in wastewater, but rather require implementation of measures to reduce the release of volatile HAPs en

36 76 Fed. Reg. at 29,586.

37 The Agency makes this point clear for the stripped resin limits ( see 77 Fed. Reg. at 22,867), but the same logic applies to wastewater.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 37 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com route to downstream activated sludge biotreatment. As discussed during previous meetings with the Agency, however, soluble HAPs volatilize and are emitted to the atmosphere at significantly lower rates than insoluble HAPs. Because affected sources will use wastewater strippers to meet the 1,000 ppm limit under the PVC MACT, readily strippable insoluble TOHAP components will already be removed in significantquantities prior to exposure to the atmosphere. Therefore, it is not sensible or costeffective to automatically require implementation of the provisions in the HON to cover and seal wastewater tanks, surface impoundments, containers, drain systems or oil water separators if the 1,000 ppm limit is not met.
The Working Group proposes that, if the 1,000 ppm limit cannot be met on a consistent basis over a twelve-month period, then emission estimation could bepermitted so that technically feasible suppression measures can be evaluated and costeffective options identified for reduction of HAP emissions on a site-specific basis in the downstream wastewater treatment system as a compliance alternative if fugitive HAP emissions from the PVC wastewater exceed a specified load threshold. For example, the reconsidered rule should allow modeling of the emissions from components of the wastewater treatment system downstream of the point(s) where they are first open tothe atmosphere in the PVCPU via EPA’s Water 9 modeling program, followed by a onetime field verification and development of site-specific emission factors, if the fugitive HAP emission threshold is exceeded. The Working Group suggests that the rule could require that no more than 10 – 20% of the mass of TOHAP be emitted as fugitive emissions from wastewater treatment system components upstream of the activated sludge biotreatment system as an aggressive but appropriate target, based on previous studies of methanol emissions from wastewater. 38

In conjunction with the fugitive emission restriction above, this alternative compliance approach would include a percent removal requirement during final biotreatment for the soluble HAPs. Methanol is often used as a supplemental source of biological oxygen demand (“BOD”) in biotreatment systems, 39 and is consumed very quickly in an activated sludge treatment system. Consequently, a 90% biodegradation Water 9 modeling demonstration from the concentration at the inlet to the biotreatment plant may be an appropriate percent removal requirement. This percent removal requirement may also be appropriate for the sum of biodegradable HAP ( e.g., alcohols, acetates, and aldehydes) entering the activated sludge treatment system, if these other readily biodegradable water-soluble HAPs are present on a site-specific basis. The Working Group notes that biodegradation default rates in Water 9 are conservative (usually underestimating biodegradation), such that site-specific rate constants would

38 Emissions of High-Solubility VOCs from Municipal Sewers , Report for Tischler-Kocurek and The Pharmaceutical Research and Manufacturers of America (1996), included as Attachment III

. 39 See EPA, Wastewater Management Fact Sheet: Denitrifying Filters, EPA 832-F-07-014, available at: http://water.epa.gov/scitech/wastetech/upload/2008_01_23_mtb_etfs_denitrifying.pdf ; and Clifton T. Jackson, Methanol, Denitrification and Safety, Water Env. & Tech, pp. 53-54 (July 2013), included as Attachment IV

.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 38 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com likely be necessary to demonstrate 90% biodegradation of the TOHAP entering the biotreatment process under this approach.
D. EPA Should Retain the VCM Limit for Existing Major and Area Source Facilities As noted earlier, it is appropriate for EPA to set a separate vinyl chloride wastewater limit because vinyl chloride is the predominant ingredient in all but the Dow Midland resin recipe, and wastewater strippers are specifically designed and optimized to remove vinyl chloride. In the final PVC MACT, the Agency set the vinyl chloride limit in wastewater for existing facilities at 6.8 ppmw. The Working Group submits that this limit best reflects the emissions control and product variability of the best performing facilities in the industry, and should be retained.
As part of the Section 114 request 30-day wastewater sampling campaign, EPA required the industry to separately sample the vinyl chloride concentration in wastewater. The Working Group submits, however, that vinyl chloride data from the 30- day sampling campaign is not the appropriate data set to use for setting the MACT floor, as it fails to capture the wide variability in products produced by the PVC and copolymer industry. Table 10 presents the number of products that could be produced annually at each facility and indicates the percentage of those products that actually were sampled at each facility during the 30-day wastewater sampling period.

Table 10 : Product Mix Addressed by 2013 Section 114 W astewater S ampling
Facility Available Grades Sampled Grades not Sampled No. Percent No. Percent
Axiall* Aberdeen 7 5 71% 2 29% Axiall* Plaquemine 17 9 53% 8 47% Formosa Point Comfort 15 4 33% 10 67% Formosa Baton Rouge 15 8 53% 7 47% Formosa SPVC 20 9 45% 11 55% Formosa Delaware 14 12 86% 2 14% MexiChem** Henry 12 12 100% 0 0% MexiChem** Pedricktown 11 11 100% 0 0% OxyVinyls Deer Park 9 4 44% 5 56% OxyVinyls Pasadena 6 5 83% 1 17% OxyVinyls Pedricktown 10 5 50% 5 50% Shintech Addis 12 4 33% 8 67% Shintech Plaquemine 12 2 17% 10 83% Shintech Freeport 12 12 100% 0 0% Westlake Calvert City 1 1 100% 0 0% Westlake Geismar 4 4 100% 0 0% Totals for PVC MACT WG 177 10 8 61 % 69 39 % * Formerly Georgia Gulf ** Formerly PolyOne
The chart above demonstrates that the 30-day sampling period covered only about 60% of the products and their various recipes produced by the industry in a calendar year. In contrast, during the PVC MACT rulemaking, the Working Group surveyed PVC facilities and requested complete sets of wastewater stripper data for vinyl chloride for all of calendar year 2008. This 2008 data set is as relevant now as itReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 39 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com was during the rulemaking, because the data was obtained across a longer period during which a greater number of products were produced, thereby providing greater variability than during the 2013 sampling. We recognize that as there is no continuous wastewater monitoring compliance requirement under the VCM NESHAP, the available data does vary widely from facility to facility. Some facilities collected monthly samples, whereas others collected daily or even three samples per day. In addition, the 2008 data was collected from only nine facilities in the industry. Nevertheless, the 2008 data set contains many more data points (4,297 vs. 511), and most importantly, encapsulates a full year of production and product variability.

Table 1 1 : Comparison of 2008 and 2013 Wastewater Data

Facility 2008 Data

Average (ppm) 2013 Data

Average (ppm) # Data

Points 2008 # Data Points 2013 % of Facility Product Mix Sampled 2013 % Total I ndustry

Product Mix Sampled in 2013
Axiall* Aberdeen 0.920 1.747 1,198 30 71% 2.8% Axiall* Plaquemine

-- 2.657 -- 30 53% 5.1% Formosa Point Comfort 1.581 0.200 1,095 30 33% 2.8% Formosa Baton Rouge

-- 0.042 -- 30 53% 4.5% Formosa SPVC

-- 3.041 -- 30 45% 5.1% Formosa Delaware

-- 1.205 -- 30 86% 6.8% MexiChem** Henry 1.199 7.365 50 30 100% 6.8% MexiChem** Pedricktown 1.902 4.085 12 30 100% 6.2% OxyVinyls Deer Park 0.383 0.114 51 31 44% 2.3% OxyVinyls Pasadena 0.024 0.075 47 30 83% 2.8% Shintech Addis

-- 0.084 -- 30 33% 2.3% Shintech Plaquemine

-- 0.048 -- 30 17% 1.1% Shintech Freeport 0.490 0.019 1,098 90 100% 6.8% Westlake Calvert City 0.563 0.010 423 30 100% 0.6% Westlake Geismar 1.187 1.309 323 30 100% 2.3% Totals 4 , 297 511 61 .0% N OTE : Top performers are highlighted. * Formerly Georgia Gulf ** Formerly PolyOne
With the exception of Westlake Calvert City, which upgraded its wastewater stripper after 2008, a side-by-side comparison of the facilities that submitted sampling data from both 2008 and 2013 (Table 11 ) suggests some correlation between product mix and sample quantity to the measurement of stripper performance. In some instances, the average concentration for the facility increased, while others decreased, but the ranges of performance are considered to be within the normal variation of practical performance. Critically, the 2013 data replaces two of the top five performers with two facilities that, combined, sampled just more than five percent of the industry’s product mix. Moreover, the Shintech Plaquemine data reflects sampling of only two of the 12 resins the facility produces in a year. Thus, the Working Group submits that the 2013 data provides insufficient information about actual industry performance to warrant a change from the 6.8 ppm vinyl chloride limit developed for the final rule.

III. Combined Process Vents
As we noted in Section I.B, several PVC production facilities are co-located with, or located near, other chemical manufacturing processes in other source categories, i.e. , EDC/VCM manufacturing, and share process vent control devices with theseReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 40 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com facilities. In a departure from the proposed rule, the final PVC MACT included a new subcategory to address these “PVC-combined” process vents. A process vent falls within this new subcategory if it “originates from a PVCPU and is combined with one or more process vents originating from another source category prior to being controlled or emitted to the atmosphere.” 40

The preamble to the final PVC MACT indicates that facilities in a different source category controlling vent streams from PVC and other facilities must comply with all rules applicable to their common control device, whether it is the HON, the PVC MACT, or another rule. According to the Agency: If an emission point is subject to both the PVC NESHAP and other NESHAP because emissions from two source categories are vented to the same control device, both standards apply. Multiple standards applicable to one emission point for the same pollutant are not necessarily “conflicting” or “inconsistent.” In some standards, the EPA has allowed compliance with another overlapping standard where that other overlapping standard was determined to be at least as stringent...Many NESHAP regulations provide a wide variety of compliance options, and, as such, it would be a difficult task to identify in advance which is the most stringent requirement in each case. 41 In contrast, Section 63.11865 of the rule expressly states that the PVC MACT does not apply to chemical manufacturing process units that produce VCM or other raw materials used to produce PVC. As we discuss further below, these cross-category requirements create a disturbing precedent and are offensive to fundamental notions of notice, due process, and fairness. Even if the Agency can overcome these fundamental deficiencies, as currently drafted, the combined process vent provisions have raised significant compliance questions and concerns, which are addressed below.
A. Applicability of PVC-Combined Limits to Non-PVC Facilities Violates the Clean Air Act and Fundamental Notions of Fairness and Due Process In an attempt to reconcile the apparent inconsistency between Section 63.11865 and the PVC MACT preamble language above, Agency staff distilled their view of the overlapping requirement to “the most stringent limit applies.” The limits potentially at issue are as follows:

Table 1 2 : Potential PVC

- Combined Limits Regulated HAP PVC MACT HON MACT MON MACT PVC Only PVC

- Combined

VCM 6.0 ppmv 1.1 ppmv 10 ppm (VCM NESHAP) None THC, or 9.7 ppmv 4.2 ppmv 20 ppm or 98% 20 ppm or 98% Total Organic HAP 56 ppmv 9.8 ppmv 20 ppm or 98% 20 ppm or 98%
HCl 78 ppmv 380 ppmv 0.45 kg/hr or 99% 20 ppm, 0.45 kg/hr, or 99% Dioxins/Furans 0.038 ng/dscm 0.051 ng/dscm None None

40 40 C.F.R. § 63.12005.

41 77 Fed. Reg. 22,869 (emphasis added).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 41 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com It is not clear what the Agency intends with this language, but taking the Agency’s guidance at face value, it could be interpreted to mean that a PVC-combined unit is subject to a 20 ppm HCl limit and a 0.038 ng/dscm dioxin/furan limit. The Working Group submits, that such an interpretation violates the Clean Air Act, however, as it would completely negate the establishment of the PVC-combined subcategory and the emission limits calculated therein. The converse is also true, however, and the Agency is prohibited from imposing the PVC-combined limits on sources that are already subject to the HON, MON, or other source category.
The PVC facilities at issue have long been in existence, venting to these combined streams well before the HON or MON standards were promulgated. Recognizing that the VCM NESHAP regulates both PVC and EDC/VCM facilities, EPA took great pains in promulgating the HON to integrate the EDC/VCM facilities subject to the NESHAP into the HON. 42 Thus, the PVC-combined process vents already aresubject to a MACT standard, and the Agency is prohibited from imposing the PVCcombined limits on existing and future combined HON and MON units.
The D.C. Circuit has repeatedly held that the Agency is required to set MACT standards based on emissions reductions achieved by similar sources within the same source category. 43 Thus, as the Working Group noted in Section I.B, it was impermissible for the Agency to set emission limits for the PVC-combined subcategory, which is dominated by EDC/VCM sources subject to the HON, using data from the Dow facility, which is subject to the MON. Even if the MON data is excluded, as the Working Group proposes, the Agency’s imposition of the PVC-combined limits on HON facilities is impermissible.
As an initial matter, the Agency’s imposition of the PVC-combined limits on HON units effectively creates a new HON subcategory. This is a critical issue, as HON units currently are not subject to some of the more stringent emission limits in the PVC MACT and HON/MON unit operators were not afforded the opportunity to comment on whether their control devices could meet the process vent and related operating requirements finalized in the PVC MACT for combined flow. The Agency’s error is further aggravated, however, because it broadly defines PVC-combined facilities that are potentially subject to the PVC MACT. Thus, any other source category is potentially implicated, should it choose to manage the vent stream from a PVC unit, even though the Agency limits did not consider or account for its HAP profile, assuming EPA could consider these facilities in a single category. As the D.C. Circuit recently held: ...it would certainly be arbitrary, as well as a violation of the CAA itself, for EPA to set one standard based on data already placed in another source category in light of the mutual exclusivity of the standards themselves

. 44

42 See e.g., 40 C.F.R. § 63.110(f).

43 Portland Cement Ass’n. v. EPA, 665 F.3d 177, 188 (D.C. Cir. 2011).

44 665 F.3d at 186.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 42 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Although the Court was addressing the relationship between commercial and industrial solid waste incinerator requirements, on the one hand, and MACT requirements on the other, the principle is still relevant here. Otherwise, if the Agency could simply create new categories and related limits for existing MACT in a new MACT standard, there would be no meaning to the MACT source categories or the development and procedural requirements imposed by the Act.
The Working Group recognizes that the Agency has an obligation to “deal with newly acquired evidence in some reasonable fashion,” 45 and to reexamine its approach if significant factual predicates change. That is not the case here, however. There has been no significant change in industry operations. Indeed, PVC-combined facility configurations have not changed since the HON was promulgated. In this regard, it is important to remember that PVC units recover over 90% of the vinyl chloride used as a raw material. Thus, venting vinyl chloride waste gas from a PVC unit to a common control device, which is a very small amount compared to the waste gas from EDC/VCM production, is the most economical, energy-efficient, and environmentally correct option, where feasible. For example, the use of a common combustion control device at an EDC/VCM/PVC facility yields less emissions of nitrogen oxide and greenhouse gases than if that facility had to construct a new PVC-only control device. The PVC-only device would emit additional NOx and GHG emissions due to the combustion of additional natural gas.
Even if there were significant changes to PVC-combined facility configurations, however, the Agency would have an obligation to conduct a more thorough, expansive, and public assessment. As the D.C. Circuit noted, “[i]t is not absurd to require that an agency’s right hand take account of what its left hand is doing.”
B. At a Minimum, EPA Must Clarify that the PVC-Combined Emission Limit Apply at the Outlet of the Emission Control DevicesAssuming, for the sake of argument, that EPA can promulgate the PVCcombined process vent limits, the Working Group is not simply concerned with the imposition of numerical emission limits on HON facilities, but more importantly, with parametric and other requirements that are either not relevant to, or conflict with, the HON operations. For example, the Working Group noted in its petition for reconsideration that 40 C.F.R. § 63.11940(c)(2) of the final PVC MACT requires the installation of the following equipment on HCl scrubbers: pressure gauges; a temperature monitoring device at the scrubber gas stream exit; or a specific gravity device. In contrast, the HON does not require any other monitoring devices beyond that specified in 40 C.F.R. § 63.114(a)(4), nor is it certain that this equipment would be appropriate for control devices generally regulated under the HON.
Similarly, Section 63.11925(d)(5)(ii) of the final PVC MACT rule requires the use of CPMS averaging times that are specified in Table 5 of the PVC MACT. Table 5 calls for three-hour averaging for thermal oxidizers and scrubbers, whereas the HON

45 Id. at 187 (citing Catawba Cnty. v. EPA , 571 F.3d 20, 45 (D.C. Cir. 2009).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 43 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com requires the daily averaging of parametric limits. 46 Based on discussions with Agency staff during the July 23 rd meeting and the discussion in the preamble to the final rule, it appears that the Agency intended the PVC-combined emission limits in Table 1 and Table 2 to apply at the outlet of the control device, but that no other PVC MACT requirements would apply to a non-PVC production unit: If a PVCPU uses a control device already subject to another Part 63 MACT rule such as the HON, then the facility may meet both sets of standards as applicable to the emission point or may choose to separate the two emission streams and route them to separate control devices, each complying with applicable requirements in the respective MACT standard

. 47
Such an interpretation is consistent with the circumstances under which the data underlying the PVC-combined limits was collected: it was obtained from HON units, running at their representative maximum operating conditions, and pursuant to CPMS and permit requirements established under the HON.

46 40 C.F.R. § 63.188(a)(2).

47 77 Fed. Reg. 22,869.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 44 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Figure 9 : PVC MACT/HON OverlapReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 45 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Although the numerical emission limits would apply at the outlet of the control device, those limits are based on HON units operating pursuant to the HON requirements as illustrated in Figure 9 . The Working Group submits that Figure 9 reflects the Agency’s intent: a process vent control device that is subject to the HON (in green) and which is receiving vent streams from an EDC/VCM unit subject to the HON (in green) and from a PVCPU subject to the PVC MACT (in red).
The Agency can easily revise the regulatory language of the final rule to make this intent clear by adding the underlined text below to 40 C.F.R. §§ 63.11140(c), 63.11865, and 63.11870: § 63.11865 Am I subject to the requirements in this subpart? You are subject to the requirements in this subpart if you own or operate one or more polyvinyl chloride and copolymers production process units (PVCPU) as defined in § 63.12005 that are located at, or are part of, a major source of hazardous air pollutants (HAP) emissions as defined in § 63.2. The requirements of this subpart do not apply to research and development facilities, as defined in section 112(c)(7) of the Clean Air Act, or to chemical manufacturing process units, as defined in § 63.101, that produce vinyl chloride monomer or other raw materials used in theproduction of polyvinyl chloride and copolymers.; except that the PVCcombined process vent emission limits in Tables 1 and 2 shall apply to the control devices at chemical manufacturing process units when such control devices are used to control process vents from a PVCPU and all such control devices shall at all times be subject to the following sections of this subpart: [Working Group recommends that Agency insert the list of sections that should apply]

. In addition, the Agency should clarify for offsite control devices that the PVC MACT applies to the PVCPU closed vent system piping from the point it leaves the PVC affected source facility until it reaches the control device at the offsite EDC/VCM unit or is combined with the EDC/VCM vent stream en route to the control device. § 63.11140 Am I subject to this subpart? (b) On or before April 17, 2012, this subpart applies to each new or existing affected source. The affected source is the collection of all equipment and activities in vinyl chloride service necessary to produce PVC and copolymers. For purposes of complying with the PVC-combined process vent emission limits in Tables 1 and 2, the affected source includes the PVCPU closed vent system piping up to the point where it commingles with vents from another source category, or enters into the control device. An affected source does not...

§ 63.11870 What is the affected source of this subpart? ...(b) The polyvinyl chloride and copolymers production affected source is the facility wide collection of PVCPU, storage vessels, heat exchange systems, surge control vessels, wastewater and process wastewaterReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 46 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com treatment systems that are associated with producing polyvinyl chloride and copolymers. For purposes of complying with the PVC-combined process vent emission limits in Tables 1 and 2, the affected source includes the PVCPU closed vent system piping up to the point where it commingles with vents from another source category, or enters into the control device.

The Agency also should revise the headings to Tables 5 and 7 to make clear that the parametric monitoring requirements apply only to PVC-only units as follows (new language is underlined):
TABLE 5 TO SUBPART HHHHHHH OF PART 63—OPERATING PARAMETERS, OPERATING LIMITS AND DATA MONITORING, RECORDING AND COMPLIANCE FREQUENCIES FOR PVC-ONLY PROCESS VENTS
TABLE 7 TO SUBPART HHHHHHH OF PART 63—CALIBRATION AND ACCURACY REQUIREMENTS FOR PVC-ONLY CONTINUOUS PARAMETER MONITORING SYSTEMS
C. Building Block Approach to Combined Limits Overcomes Statutory and Data Deficiencies Beyond the statutory deficiencies and needed clarifications discussed above, the Agency acknowledged that it had a very limited data set with which to calculate the PVC-combined limits. 48 Consequently, the PVC-combined limits may not accurately reflect the actual performance achieved by the best performing sources. As an initial matter, the Working Group noted in Section I.B, that the Dow Midland facility simply is not relevant to setting PVC-combined limits that will predominantly affect process vent control devices at EDC/VCM facilities. For example, the Midland emissions data was used to set the PVC-combined dioxin/furan limit, but the facility does not combust chlorinated waste gas streams to the same degree that an EDC/VCM unit does. As we noted, the Midland facility manufactures a PVDC resin copolymer that uses significantly less vinyl chloride than PVC resins and so will use and vent significantly less vinyl chloride than a unit that manufactures vinyl chloride as its primary product. Accordingly, the PVC-combined limits should be recalculated without the DOW data, as set out in Table 13 :

Table 1 3 : Proposed Recalculated PVC

- Combined Process Vent Limits

Pollutant Floor Component Existing Source New Source Vinyl Chloride 99% UPL 0.45 0.00569 ppmvd @ 3% O2 3xDL 0.55 0.55 MACT Floor 1 0.56 0.56

48 Revised Maximum Achievable Control Technology (MACT) Floor Analysis for the Polyvinyl Chloride and Copolymers (PVC) Production Source Category , Docket Document No. EPA-HQ-OAR-2002-0037- 0193 at 7.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 47 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Table 1 3 : Proposed Recalculated PVC

- Combined Process Vent Limits Pollutant Floor Component Existing Source New Source
HCl 99% UPL 370.8 1.312 ppmvd @ 3% O2 3xDL 0.0 0.0 MACT Floor 1 380.0 1.40

CDD/CDF TEQ 99% UPL 0.2839 0.07548 ng/dscm @ 3% O2 3xDL 0.0335 3.35E-02 MACT Floor 1 0.2900 0.0760

THC 99% UPL 7.64 2.083 ppmvd as propane @ 3% O2 3xDL 2.27 2.27 MACT Floor 1 7.7 2.27

TOHAP 99% UPL 13.46 5.844 ppmvd @ 3% O2 3xDL 5.42 5.42202 MACT Floor 1 14.00 5.90 1 - MACT Floors rounded UP - two significant figures
In addition, the Agency can readily address the deficiencies discussed in Sections III.A and III.B, by allowing the optional use of a “building block” approach to combine the PVC and EDC/VCM ( i.e. , HON) process vent limits, as an alternative to complying with the Table 1 and Table 2 PVC-combined limits.
Under this approach, the PVC-only and HON process vent limits would be blended based on a weighted average of the mass flow from the two units, calculated based on emission profiles of the process vent streams prior to the thermal oxidizer or where the two vent streams are mixed. For example, both the PVC MACT and the HON include process vent emission limits for total hydrocarbons (“THC”). If, as Figure 9 illustrates, the PVC production unit accounts for 5% of the THC mass flow to the thermal oxidizer and the EDC/VCM production unit accounts for 95% of the THC mass flow to the thermal oxidizer, then the blended limit would be calculated as set out in Table 14

. Table 1 4 : Example Blen ded Limit Calculation for THC PVC MACT (PVC-Only) HON

THC Limit 9.7 ppmv 20 ppmv Inlet THC Mass 5% 95% Blended Limit 0.05 x 9.7 + 0.95 x 20 = 19.5 ppmv Similarly, for vinyl chloride, the PVC-only vinyl chloride limit would be blended with the HON vinyl chloride limit (which actually incorporates the VCM NESHAP vinyl chloride limit) based on a weighted average of the mass flow of vinyl chloride. If the PVC production unit accounts for 20% of the VC mass flow to the thermal oxidizer and the EDC/VCM production unit accounts for 80% of the VC mass flow to the thermal oxidizer, then the blended limit would be calculated as set out in Table 15

.

Table 1 5 : Example Blended Limit Calculation for Vinyl Chloride PVC MACT (PVC-Only) HON
Vinyl Chloride Limit 6.0 ppmv 10 ppmv Inlet Vinyl Chloride Mass 20% 80% Blended Limit 0.20 x 6.0 + 0.80 x 10 = 9.2 ppmvReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 48 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com The same approach would be an alternative compliance approach for all HAPs for which both MACT standards include a process vent emission limit, except for dioxin/furan emissions. The HON does not include a dioxin/furan limit. The Working Group is aware, however, that the Agency intends to promulgate an EDC/VCM MACT in the near future, which presumably will include a process vent dioxin/furan limit and would make a blended limit possible. In the interim, the Working Group recommends that a facility using a blended limit for other HAPs should be required to comply with the recalculated PVC-combined limit for dioxin. The data used by the Agency to set the limits clearly indicates that the vent streams from an EDC/VCM facility can result in higher levels of dioxin to be formed in the thermal oxidizer. Thus, it would be infeasible for a combined vent stream to comply with the PVC-only limit.
The reconsidered PVC MACT should make clear that a facility may use the building block approach when both source categories include a limit for the particular HAP, but must comply with the recalculated PVC-combined limit when one of the source categories does not include a limit for that HAP. This optional approach will ensure that the emissions from the PVC production unit meet the PVC MACT limits and achieve the required HAP reductions. It would also ensure that EDC/VCM production units continue to meet their current requirements under the HON. In light of the limited data set used to set the PVC-combined process vent emission limits, as well as the statutory deficiencies identified with the Agency’s approach, the building block approach provides industry with necessary flexibility, in a manner that fully complies with the Act by allowing a demonstration that two or more MACT or GACT limits are met, and that is based on the actual performance of control devices used for mixed source category vent streams.
IV. Bypasses from Closed Vent Systems
As the Working Group noted in our April 5, 2013 letter recommending clarifications to the final rule, there is a fundamental problem with the “closed vent system” (“CVS”) definition. This problem is most evident when reviewing the requirements in the final rule related to bypasses. In order to ensure that PVC operators detect and identify bypasses, the final PVC MACT requires the installation of a bypass flow indicator on valves and other components that are capable of diverting a regulated vent stream away from the control device directly to the atmosphere. In the alternative, facilities can use a car-seal or lock-and-key to secure valves and other components in a non-diverting position, subject to monthly inspections and recordkeeping.

These requirements would cover thousands of valves and other pieces of equipment at each PVC facility and would prohibit any maintenance activity involving the opening of these valves or other pieces of equipment. The Working Group submits that three logical revisions to the rule would resolve the current issues with the bypass provisions: (1) revise the definition of the CVS to begin at the exit from the recovery system; (2) exempt maintenance-type valves from the bypass requirements; and (3) clarify that opening equipment ( e.g. , for maintenance) is not a bypass, provided the equipment opening requirements are met.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 49 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com A. The Recovery System is Not Part of the Closed Vent System As the Working Group has previously indicated, PVC and copolymer facilities use an extensive recovery system to recover monomers in gases from the manufacturing process. Through the recovery system, the vast majority of vinyl chloride monomer and other materials are condensed and recycled back to the process as valuable raw materials. In a practical sense, the monomers and other materials do not become “contaminants” in a “vent” until they pass the last recovery equipment and are in the vent stream headed to the control device ( i.e. , the thermal oxidizer or vent gas absorber) and subsequently are discharged. As a result, it is vital that the Agency revise the definition of a closed vent system to reflect the use of the recovery system.
Two recent CAA rulemakings, the Oil and Natural Gas Production Facilities MACT and the Oil and Natural Gas Sector NSPS reconsideration, provide a template for addressing the issues in the bypass provisions by better defining the scope of the CVS. Specifically, the Oil and Natural Gas Production Facilities MACT does not classify recycled vapors as part of the CVS, which allows process gas to vent back to the process. 49 Similarly, the Oil and Natural Gas Sector NSPS does not classify vapors that are routed to a “flow line” ( i.e. , back to the process for a useful purpose) as part of a CVS. 50

The Working Group recommends that EPA amend the definitions at Section 63.12005 to revise the scope of the CVS, and to add a new definition for the recovery system (new language is underlined; deletions are in strikethrough): Closed-vent system means a system that is not open to the atmosphere and is composed of piping, ductwork, connections, and, if necessary, flow inducing devices that collect or transport gas or vapor from an emission point to a control device. If gas or vapor from regulated equipment is routed to a process (e.g., returned back to the process), the conveyance system is part of the recovery system and shall not be considered a closed-vent system. The continuous process vent from the recovery system to the control device is the closed vent system.... Control device means, with the exceptions noted in this definition, a combustion device, recovery device that vents to the atmosphere, recapture device or any combination of these devices used to comply with this subpart. Process condensers are not control devices. For the purposes of this subpart, if gas or vapor from regulated equipment is used, reused, or returned back to the process, then the recovery system, including piping, connections, and flow inducing devices, is not considered to be a control device or closed-vent system.... Recovery system means the collection of process equipment including recovery devices that is capable of and normally used for the purpose of

49 40 C.F.R. § 63.761.

50 78 Fed. Reg. 22,125, 22,141 (April 12, 2013) (to be codified at 40 C.F.R. § 60.5411(c)(1)).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 50 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com recovering vinyl chloride monomer or other materials for use or reuse within the PVCPU.
The Working Group also recommends that the Agency make related changes to the initial and continuous compliance requirements for process vents at Section 63.11925(b) to address the change in the scope of the CVS (new language is underlined) as follows: Closed vent systems and control devices. Each batch process vent, continuous process vent and miscellaneous vent that is in HAP service must be routed through a closed vent system to a control device if the gas or vapor from regulated equipment is not routed to a process or the recovery system. All gas streams routed to the closed vent system and control device must be for a process purpose and not for the purpose of diluting the process vent to meet the emission limits in Table 1 or 2 to this subpart...
The Working Group acknowledges that global changes may be required in the various “vent” definitions and related provisions of the rule to address the distinction between the CVS and the recovery system. To avoid further complicating this discussion, however, the Working Group has limited its recommendations in this section to the provisions with the greatest substantive impact.
B. An Exemption for Maintenance-Type Valves Must be Included As currently worded, the final PVC MACT does not distinguish between maintenance type valves, which are not truly capable of diverting the vent stream from a control device to the atmosphere, and true bypasses which do vent directly to the atmosphere. In addition, the PVC MACT regulates as a bypass low leg drains, high point bleeds, analyzer vents, and open-ended valves or lines, which are needed to safely maintain process equipment and cannot be opened without first complying with the equipment opening provisions.

The Oil and Natural Gas Production Facilities MACT and the Oil and Natural Gas Sector NSPS reconsideration provide a template for addressing maintenance-type valves. Both rules provide an exemption from bypass monitoring requirements for low leg drains, high point bleeds, analyzer vents, open-ended valves or lines, and safety devices. 51 Compliance with equipment opening requirements (which have to be met before opening such equipment) has been ingrained in the PVC industry for over 30 years, significantly longer than any other source category in the chemical industry. Accordingly, the Working Group sees no reason that maintenance-type valves should not be removed from the CVS bypass monitoring requirements. Such a change can easily be accomplished by amending Section 63.11930(c) to add a new subparagraph (c)(3) as follows:

51 40 C.F.R. § 63.771(c)(3)(ii); 78 Fed. Reg. at 22,141 (to be codified at 40 C.F.R. § 60.5411(c)(3)(ii)).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 51 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Low leg drains, high point bleeds, analyzer vents, open-ended valves or lines, and safety devices are not subject to the requirements of paragraph (c)(1) or (2) of this section.

Maintenance-type values remain subject to the general prohibition on uncontrolled discharges to the atmosphere and the equipment opening requirements. Therefore, the proposed language above does not provide an exemption for uncontrolled emissions from affected sources.
C. Equipment Openings Are Not Bypasses As the Working Group stated in its petition for reconsideration, the opening of valves and other equipment during routine maintenance activities and other operations, even after the rule’s equipment clearing/opening procedures have been performed and associated emission limits are met, constitutes a violation under the final rule as currently written. It appears that a bypass would include the opening of valves and other equipment during routine maintenance and other operations, and each such bypass release is declared a “violation,” regardless of the circumstances, even after the rule’s equipment clearing/opening procedures have been performed such that the equipment or valve is no longer “in HAP service.”
We understand from our discussions with Agency staff that this result was not intended, but without a change to the regulatory language, no other possible interpretation is viable. Accordingly, the Working Group submits that the Agency must revise the bypass requirements in Section 63.11930(c) to make clear that a “bypass” is not a violation when the equipment opening provisions are met, as follows (new language is underlined): Bypass. For each closed vent system that contains a bypass as defined in § 63.12005 (e.g., diverting a vent stream away from the control device), you must not discharge to the atmosphere through the bypass. Any such release constitutes a violation of this rule unless the equipment opening provisions in section 63.11955 are met. The use of any bypass diverted to the atmosphere during a performance test invalidates the performance test. You must comply with the provisions of either paragraph (c)(1) or (2) of this section for each closed vent system that contains a bypass that could divert a vent stream to the atmosphere.
This change would resolve the textual conflict between the bypass provisions and the equipment opening requirements of the final rule.

V. Emission Profiles
The final rule added a new requirement in Section 63.11925(g) for PVC facilities to “characterize each process vent by developing an emissions profile for each contributing continuous process vent, miscellaneous vent and batch process vent,” as part of their initial and continuous compliance demonstrations. As the Working Group stated in the petition for reconsideration, this new requirement is unnecessary andReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 52 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com overly burdensome to the PVC industry: it will require the development of hundreds of new emission profiles from a PVCPU. In the final rule, the Agency mistakenly states that PVC and copolymer facilities currently develop emission profiles: We expect facilities to already have inventories and previous test results available to develop their emissions profile. All of the facilities that provided information in response to the August 21, 2009, PVC CAA section 114 survey, developed emission profiles. Additionally, we are allowing the emissions profile to be based on engineering assessment or measurement. Because of these reasons, we do not anticipate additional burden from this requirement. 52

In truth, the final rule requires much more than PVC facilities have previously developed. The plain language of the final rule requires emission profiles for each batch and continuous process vent and each potential emission episode, an exercise that is not only unprecedented and incredibly burdensome, but also of negligible value.
We understand that EPA generally is concerned about facilities diluting their vent streams en route to the control device in order to meet process vent emission limits. The Agency would use the emission profiles to develop mass-balance calculations that allow it to detect whether dilution is occurring. As we pointed out during our May 22 nd meeting, however, process vent dilution simply is not an issue in the PVC industry. A PVC facility is designed to prevent inerts and non-condensable materials from entering the process stream. Inerts require increased pressure in the process, increasing the risk of pressure relief device (“PRD”) releases or other malfunctions, and interfere with the recovery of VCM in the recovery system. More importantly, PVCPUs are designed to maximize raw material value by recovering unreacted VCM and reusing it in the process. A PVC facility would not choose to introduce air into the recovery system, because to do so would make recovery much more difficult and dangerous, and would result in increased raw material costs.

Moreover, the emission profiles would not provide the information needed to perform a mass-balance calculation, because PVCPUs use a recovery system. Vent streams collected from process equipment (both continuously and batch-wise) are recovered overhead and reused. The process is engineered to maximize the percent of the stream that is recovered and minimize the amount that is ultimately vented from the recovery system to a control device. As a result, the mass in the vent streams that would be measured upon existing process equipment would not equal the mass in the streams when measured at the control device. In fact, there is no correlation between the two; the flow rate to the control device is a function of the amount of contamination in the process from non-condensables.
PVC manufacturing is simply not amenable to mass balancing as EPA envisions. The mass balance formulas EPA would use to calculate the emission profiles were developed by Merck & Co., Inc. (“Merck”), a major U.S. pharmaceutical company, for

52 77 Fed. Reg. at 22,855.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 53 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com that industry. In the late 1970s, Merck developed the calculations for air permitting purposes, to assist in calculating emissions to the atmosphere from uncontrolled batch processes at its New Jersey production facility. The formula was intended to capture Merck’s operation, which was conducted in small batches on equipment that vented directly to the atmosphere in order to demonstrate compliance with the state’s PSD Program (and justify that emission control technology was not required).

The resulting calculation methodology, which was later incorporated into the Pharmaceutical (“Pharma”) MACT for calculating uncontrolled HAP emissions, 53 envisions sources like the Merck facility that are significantly different from continuously operated PVC facilities, which have been and continue to be required to control all (VCM) emissions. Specifically, the Merck approach was manageable for Pharma facilities, because:

 Pharma production uses a campaign-style process. Some of the process equipment was operated only two to three months per year, unlike PVC process equipment, which is operated virtually around the clock.

 The Pharma production process consists of defined operating steps that yield a highly specified product at the facility within small pieces of equipment ( e.g., 500 gallon vessels). In contrast, PVC production involves more widely diverging operating conditions that yield more varied final product configurations produced in large containers, e.g. , 18,000 gallons, or larger, reactors.

 At the time, each Merck recipe had 15-30 emission episodes over 10-15 pieces of equipment per batch. A typical PVC facility, on the other hand, has hundreds of episodes over 20-30 pieces of equipment per batch.
The most important difference between the PVC and Pharma industry is that unlike the original small Pharma operations for which the formulas were developed, PVC process equipment does not vent directly to a control device or the atmosphere. Rather, all process equipment is hard piped to the recovery system. As noted above, a notable portion of the VCM and other HAP-containing materials are recovered and returned back to the process, and the non-condensables are hard piped to the control device. Consequently, no upstream emission profile can correctly correlate emissions from process equipment with the vent stream that actually flows into the control device. Therefore, the proposed emission profile formula is inapplicable to the PVC industry and should be deleted from the PVC MACT rule.
At the July 23 meeting, Agency staff agreed that emission profiles of vent streams routed to the recovery system would not be useful. As the Working Group understands, it is EPA’s intent to require emission profiles for the CVS after the recovery system. Accordingly, the Working Group recommends that the Agency amend the PVC MACT as suggested in Section IV concerning bypasses, which would exclude the recovery system from the CVS. Concurrently, the emission profile provisions should be revised to make clear that emission profiles must be developed for the CVS and the

53 40 C.F.R. Part 63, Subpart GGG.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 54 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com vent streams that feed directly into the CVS only. Suggested language for Section 63.11925(g) is provided below (new language is underlined; deletions are in strikethrough): (g) Emission profile. You must characterize the closed vent system and each vent stream that is routed into the closed vent system each process vent by developing an emissions profile for each contributing continuous process vent, miscellaneous vent and batch process vent according to paragraphs (g)(1) through (3) of this section. This requirement does not apply to the recovery system or process vents that are routed to the recovery system.
The Working Group also suggests that paragraph (g) should be moved from Section 63.11925, which applies to process vents, to the more apt Section 63.11930, which applies to the CVS. These changes would eliminate the confusion created by the current wording of paragraph (g), which indicates that emission profiles must be developed for each process vent.

During the July 23 meeting, the Agency also indicated that it would be acceptable to use engineering judgment and stack tests to develop emission profiles as an alternative to the formulas in Section 63.11950. Indeed, Section 63.11925(g)(2)(iv) currently permits the use of engineering judgment when developing emission profiles for continuous process vents. For batch process vents, however, which are covered by Section 63.11950, the use of engineering judgment requires preapproval by the Administrator. Accordingly, the Working Group recommends the following revisions to Section 63.11950 to reflect the Agency’s intended approach and harmonize this provision with Section 63.11925(g)(2)(iv) on continuous process vents (new language is underlined; deletions are in strikethrough): When developing your emission profiles for batch process vents as required in § 63.11925(g), except as specified in paragraph (i) of this section, you must calculate emissions from episodes caused by vapor displacement, purging a partially filled vessel, heating, depressurization, vacuum operations, gas evolution, air drying, or empty vessel purging, using the applicable procedures in paragraphs (a) through (h) of this section.

... (i) Engineering assessments. You must may conduct an engineering assessment to calculate HAP emissions or emission episodes from each process vent as an alternative to the procedures in paragraphs (a) through (h) of this section. that are not due to vapor displacement, partially filled vessel purging, heating, depressurization, vacuum operations, gas evolution, air drying or empty vessel purging. An engineering assessment may also be used to support a finding that the emissions estimation equations in this section are inappropriate. All data, assumptions and procedures used in the engineering assessment must be documented, areReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 55 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com subject to preapproval by the Administrator, and must be reported in the batch precompliance report. An engineering assessment should include, but is not limited to, the items listed in paragraphs (i)(1) through (4) of this section. (1) Previous test results provided the tests are representative of current operating practices at the process unit. (2) Bench-scale or pilot-scale test data representative of the process under representative operating conditions. (3) Maximum flow rate, HAP emission rate, concentration, or other relevant parameter specified or implied within a permit limit applicable to the process vent. (4) Design analysis based on accepted chemical engineering principles, measurable process parameters, or physical or chemical laws or properties. Examples of analytical methods include, but are not limited to the following: (i) Use of material balances based on process stoichiometry to estimate maximum organic HAP concentrations. (ii) Estimation of maximum flow rate based on physical equipment design such as pump or blower capacities. (iii) Estimation of HAP TOC or organic HAP concentrations based on saturation conditions. (iv) Estimation of maximum expected net heating value based on the vent stream concentration of each organic compound or, alternatively, as if all TOC in the vent stream were the compound with the highest heating value.

VI. Vent Gas Absorbers
As we discussed extensively in Section III, the final PVC MACT limits for process vents are based on the use of thermal oxidizers as the control device. Three PVC facilities, however, use vent gas absorption (“VGA”) as vinyl chloride monomer (“VCM”) recovery systems, 54 which represent a radically different technology for controlling emissions from these streams.
Unlike a thermal oxidizer, VGAs are not combustion devices and, accordingly, have significantly different emissions to the atmosphere. Dioxins, HCl, and greenhouse gases are not produced by this technology; isooctane is the measureable component in the THC measurement. Critically, the outflow from the VGA is intermittent and occurs at a very low rate. In contrast, the outlet volume flow from a thermal oxidizer is more than 100 times that from a VGA or 13.4+ dry standard cubic meters per minute (“dscmm”)

54 VGAs are located at the PolyOne facilities at Pedricktown, NJ and Henry, IL. The OxyVinyls facility at Pedricktown, NJ shares the VGA at PolyOne’s Pedricktown, NJ facility.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 56 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com versus 0.0781 dscmm, respectively. 55 As a result, the concentration value or ppm volumetric dry (“ppmvd”) for all HAPs or THC measured from intermittent VGA emissions is very high, but the actual mass emission rate is extremely low.
Thus, in its comments on the proposed rule, the Working Group argued that the Agency should recognize that VGAs are a “recovery” control technology, and requested that VGAs be regulated as a separate subcategory with equivalent MACT floor performance limits based on mass emission rates. 56 Based on discussions with the Agency during the July 23 meeting, however, it appears that the Agency is unwilling to create a subcategory for VGAs. In the absence of a separate subcategory for sources that employ VGAs, the Working Group believes that an alternative emission limit is necessary. Indeed, EPA acknowledged as much when it noted that it did consider: ...setting alternative formats for the process vent emission limits. However, we did not have sufficient information provided from industry on process vent stream flow rates and concentrations to develop or evaluate other formats, such as mass emission rates. 57

The Working Group submits that there is sufficient information in the docket to calculate an alternate limit. As we understand from past discussions with the Agency, EPA would support the use of an alternate emission limit by VGAs, provided that such limit is “equivalent” to the current concentration limit. Thus, the Working Group proposes that the Agency calculate mass emission limits using the same top five PVC-only facilities used to set the concentration limits.

Data on stream flow rates and concentrations for all process vents were provided to EPA as part of the response to the Agency’s Section 114 request. Flow rate and concentration for each device, including data for VGAs, can be found in the various EPA spreadsheets submitted as part of each PVC facility’s stack sampling submission and posted to the rulemaking docket. 58 An extensive report of the stack sampling performed at each PVC facility also was prepared by industry, describing in detail the sampling locations, quality assurance and quality control steps, and sample collection and analytical procedures. These reports, which were submitted as part of each Working Group member’s Section 114 response, also provided flow rate and concentration information, including THC.
Using this data, the PVC-only limits, and the revised PVC-combined limits from Section III above, the Working Group calculated mass-based emission limits that are

55 Based on the concentration database used for the MACT limit calculations.

56 Docket Document No. EPA-HQ-OAR-2002-0037-0146, at 52.

57 77 Fed. Reg. 22,869.

58 See Docket Document No. EPA-HQ-OAR-2002-0037-0107.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 57 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com equivalent to the concentration-based limits. 59 The Working Group proposes the calculation of mass-based limits by adjusting the concentration limits using the flow rate data currently in the record for the top five PVC-only and PVC-combined facilities, respectively. The average flow rate of the top five performers in each process vent subcategory was used as the common factor to convert the concentration limits to a mass-based limit, as follows:

Table 16: Proposed Mass-Based Process Vent Emissions Limits

MACT Floors for PVC Only Facilities Calculated Concentration Limit Converted Mass Limit

Pollutant Floor

Component Existing Source New Source Existing

Source New Source
Vinyl Chloride 99% UPL 6.00 0.00500 0.0279 0.0000 ppmvd @ 3% O2 3xDL 0.55 0.5523 0.0026 0.0026 MACT Floor 1 6.00 0.56 0.028 0.0026

HCl 99% UPL 77.1 0.162 0.2093 0.0004 ppmvd @ 3% O2 3xDL 0.050 5.01E-02 0.0001 0.0001 MACT Floor 1 78.0 0.17 0.21 0.00045

CDD/CDF TEQ 99% UPL 0.0184 0.00428 0.0053 0.0012 ng/dscm @ 3% O2 3xDL 0.0374 3.74E-02 0.0107 0.0107 MACT Floor 1 0.0380 0.0380 0.011 0.011

TOHAP 99% UPL 55.8 0.217 0.6018 0.0023 ppmvd @ 3% O2 3xDL 5.4 5.42E+00 0.0585 0.0585 MACT Floor 1 56 5.50 0.61 0.059

MACT Floors for PVC Combined Facilities Calculated Concentration Limit Converted Mass Limit

Pollutant Floor

Component Existing Source New Source Existing

Source New Source
Vinyl Chloride 99% UPL 0.42 0.00569 0.0020 0.0000 ppmvd @ 3% O2 3xDL 0.55 0.55 0.0026 0.0026 MACT Floor 1 0.56 0.56 0.0026 0.0026

HCl 99% UPL 370.8 1.312 1.0068 0.0036 ppmvd @ 3% O2 3xDL 0.0 0.0 0.0001 0.0001 MACT Floor 1 380.0 1.40 1.1 0.0036

CDD/CDF TEQ 99% UPL 0.2839 0.07548 0.0811 0.0216 ng/dscm @ 3% O2 3xDL 0.0335 3.35E-02 0.0096 0.0096 MACT Floor 1 0.2900 0.0760 0.082 0.022

TOHAP 99% UPL 13.46 5.844 0.1452 0.0630 ppmvd @ 3% O2 3xDL 5.42 5.42202 0.0585 0.0585 MACT Floor 1 14.00 5.90 0.15 0.064 1 - MACT Floors rounded UP - two significant figures
The accompanying database is enclosed as Attachment V and was submitted to the Agency on electronic media via separate cover.

59 Although VGAs are only currently used by PVC-only facilities, the Working Group recognizes that an alternative emission limit should be available to any facility, and has accordingly calculated these limits for both the PVC-only and the PVC-combined subcategories.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 58 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com The Working Group’s approach does not differ significantly from that used by EPA, as we recognize that process vent streams at different facilities have different flow rates based on differences in the thermal oxidizers. To address this issue, the Agency set the process vent emission limits normalized to 3% O 2 . As the Agency’s MACT floor analysis memorandum states: Correction of pollutant concentrations to specified percent oxygen normalizes emissions data and allows for comparison of concentrations from sources with varying oxygen concentrations in the emission stream. Although typically applicable to combustion sources, such as thermal oxidizers, concentration correction for oxygen also applies to the use of VGA systems, such as those located of the PolyOne facilities as oxygen concentrations varied from 12.5 percent to 19.5 percent between the PolyOne facilities. 60

The important point to remember is the VGA technology deals with only the process vent stream without the additional air for combustion. That is why the VGA technology demonstrates flow rates that are 200 times lower than typical thermal oxidizers. These operating conditions, however, mean that in order to compare concentration data between a VGA and a thermal oxidizer, a standardized flow rate must be used in addition to the 3% O 2 adjustment. Establishing a standard flow rate based on the top five PVC only facilities and adjusting performance data with this standard allows a fair comparison of concentration data to be made.
A mass-based approach is optimal for such comparisons, since it excludes any need for corrections while still allowing an equivalent assessment of the VGA’s emission control performance. A concentration-based limit is workable if the data are standardized for oxygen level as well as flow as previously described.

VII. Pressure Relief Device Requirements
As the Working Group stated in the petition for reconsideration, the final rule requirements for some form of lift indication or flow detection, and alarms on all PRDs that discharge directly to the atmosphere to notify facility operators and determine the duration of a PRD release after it has occurred are unnecessary. Moreover, Working Group members have been unable to identify any single device that can be installed on a PRD and perform all the functions sought by EPA: provide lift indication or flow detection, notify facility operators, and determine the duration of a PRD release. Additionally, changes to valve stems to accommodate lift indicators on PRDs could put the device out of compliance with American Petroleum Institute (“API”) and/or American Society of Mechanical Engineers (”ASME standards”). 61 Consequently, this

60 Revised Maximum Achievable Control Technology (MACT) Floor Analysis for the Polyvinyl Chloride and Copolymers (PVC) Production Source Category , Docket Document No. EPA-HQ-OAR-2002-0037- 0193 at 37.

61 Insurance providers require complaince with API and/or ASME standards for the proper design of all pressurized and vacuum equipment.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 59 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com requirement is not “achievable” because the required technology is not available to PVC-affected sources.
The Working Group submits that the combination of systems and procedures currently in place at PVC facilities ( e.g. , ambient air area monitoring, process monitoring, alarms, and other systems) adequately detect PRD releases and make it entirely unnecessary to install lift indication or flow detection and alarms on all PRDs that discharge directly to the atmosphere. Indeed, in the decades that these complementary ambient air monitors, flow detection, and alarms have been operational and the industry has complied with the requirement to report the quantity of any release, we are not aware of any data suggesting that these systems are not sufficient. Consequently, the Working Group recommends the following changes to the PRD requirements in Section 63.11915(c)(1) and a new Section 63.11915(c)(2)to permit the use of these existing systems as an alternative to equipment installed directly on PRDs (new language is underlined; deletions are in strikethrough): (1) For pressure relief devices in HAP service that discharge directly to the atmosphere without first meeting the process vent emission limits in Table 1 or 2 to this subpart by routing the discharge to a closed vent system and control device designed and operated in accordance with the requirements in §§ 63.11925 through 63.11950, you must install, maintain, and operate release indicators as specified in paragraphs (c)(1)(i) and (ii) of this section or a system or combination of systems as specified in paragraph (c)(1)(iii). Any release to the atmosphere without meeting the process vent emission limits in Table 1 or 2 to this subpart, constitutes a violation of this rule. You must submit the report specified in § 63.11985(c)(7), as described in paragraph (c)(1)(iii)(iv) of this section.

... (iii) A system or combination of systems must be used to permit operators to readily detect pressure relief device discharges. This may include vinyl chloride ambient area monitoring (as required in § 63.11956), monitoring of process parameters, or similar systems. (iii)(iv) For any instance that the release indicator or the system described in paragraph (c)(1)(iii), as appropriate, indicates that a pressure relief device is open, you must notify operators that a pressure release has occurred, and, within 10 days of the release, you must submit to the Administrator the report specified in § 63.11985(c)(7). This report is required even if you elect to follow the procedures specified in § 63.11895 to establish an affirmative defense. (2) For pressure relief devices in HAP service that discharge directly to a closed vent system and control device designed and operated in accordance with the requirements in §§ 63.11925 through 63.11950 and are required to meet process vent emission limits in Table 1 or 2 to this subpart. Any release to the atmosphere without meeting the process vent emission limits in Table 1 or 2 to this subpart, constitutes a violation of thisReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 60 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com rule. You must notify operators that a pressure release has occurred, and, within 10 days of the release, you must submit to the Administrator the report specified in § 63.11985(c)(7). This report is required even if you elect to follow the procedures specified in § 63.11895(b) to establish an affirmative defense. (2) Paragraph (c)(1) does not apply to pressure relief devices in HAP service that discharge directly to a closed vent system and control device or that discharge directly to the recovery system. Any release to the atmosphere without meeting the process vent emission limits in Table 1 or 2 to this subpart constitutes a violation of this rule.
The Working Group previously recommended clarifying changes to the language in Section 63.11915 in our April 5, 2013 letter to resolve textual uncertainties on the application of the Subpart UU LDAR requirements to pumps, compressors, agitators, and other equipment. Because Section 63.11915 also includes the requirements for equipment leaks, another issue in the petition for reconsideration, the Working Group’s suggested changes for all of these issues are also submitted in a single proposal for revisions to Section 63.11915, Attachment VI to this letter. The revisions also include changes to Section 63.11915(c)(2) to address the changes to the definition of the CVS (to address bypasses and emission profiles), as suggested in Section IV of this letter, and clarify the applicability of paragraph (c)(1).
VIII. Leak Detection and Repair (“LDAR”) for Pressure Vessels
The final rule classifies any discharge from a pressure vessel closure device to the atmosphere as a violation of the PVC MACT, without first providing an opportunity to fix the leak on a timely basis. 62 As the Working Group stated in the petition for reconsideration, leak detection, coupled with prompt repair, is both the MACT floor and reflective of best practices for minimizing emissions from pressure vessels.

During the May 22 nd meeting, the Agency acknowledged that the equipment leak provisions may be unclear and need clarification. The Working Group submits that the information provided in our comments and petition for reconsideration provide sufficient support that the best performing PVC facilities currently use LDAR to manage leaks from pressure vessels. Any requirement in the PVC MACT that does not allow for LDAR to be used on pressure vessels constitutes a beyond-the-floor emission control and requires the Agency to “[take] into consideration the cost of achieving such emission reduction.” 63 Agency staff agreed during the May 22 nd meeting that the intent of Section 63.11910(c)(4) was to prohibit discharges from pressure vessel closure devices during filling, emptying, or purging, and the intent was not to prohibit the use of LDAR during normal operations. Accordingly, the Working Group recommends that the Agency revise Section 63.11910(c) for clarification (new language is underlined; deletions are in strikethrough):

62 40 C.F.R. § 63.11910(c)(4).

63 42 U.S.C. § 7412(d)(2).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 61 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com (c) For each pressure vessel used to comply with the requirements specified in Table 3 to this subpart, you must meet the requirements in paragraphs (c)(1) through (3)(4) of this section. (1) Whenever the pressure vessel is in hazardous air pollutants (HAP) service, you must operate the pressure vessel as a closed system that does not vent to the atmosphere, e.g., during filling, emptying and purging. The vent stream during filling, emptying and purging must meet the requirements of § 63.11925(a) and (b). Any venting directly to the atmosphere during filling, emptying, or purging constitutes a violation of this rule. You must submit to the Administrator as part of your compliance report the information specified in § 63.11985(b)(10). This report is required even if you elect to follow the procedures specified in § 63.11895 to establish an affirmative defense. (2) Each opening in the pressure vessel must be equipped with a closure device designed to operate such that when the closure device is secured in the closed position there are no visible cracks, holes, gaps or other open spaces in the closure device or between the perimeter of the opening and the closure device. (3) All potential leak interfaces (e.g., sight glasses; meters; gauges; sampling connections; bolted manways; and hatches) including those for closure devices must be monitored annually for leaks to confirm the conditions of no detectable emissions, as indicated by an instrument reading of less than 500 ppm above background, by the methods specified in §§ 63.11910(c)(3)(i)-(ii)using the procedures specified in § 63.11915 and you may adjust for background concentration. You must comply with the recordkeeping provisions specified in § 63.11990(b)(4) and the reporting provisions specified in § 63.11985(a)(1), (b)(1), and (b)(10). (i) Method 21 shall be used to determine the background level. The instrument shall be calibrated before use each day of its use by the procedures specified in Method 21. The following calibration gases shall be used: (A) Zero air (less than 10 ppm of hydrocarbon in air); and (B) A mixture of methane and air at a concentration of about, but less than, 500 ppm methane. (ii) Method 21 shall be used to determine the presence of leaking. All potential leak interfaces shall be traversed as close to the interface as possible. The arithmetic difference between the maximum concentration indicated by the instrument and the background level is compared with 500 ppm for determining compliance. (4) Pressure vessel closure devices must not discharge to the atmosphere. Any such release (e.g., leak) constitutes a violation of thisReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 62 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com rule. You must submit to the Administrator as part of your compliance report the information specified in § 63.11985(b)(10). This report is required even if you elect to follow the procedures specified in § 63.11895 to establish an affirmative defense.
Additionally, the Working Group believes that the Agency should revise the equipment leak provisions in the final rule to make clear that LDAR is required for pressure vessel closure devices at a leak detection level of 500 ppm, in line with current practices in the PVC industry ( i.e. , the MACT floor), by adding a new paragraph (d) as follows: (d) Requirements for pressure vessels. Pressure vessel closure devices (e.g., access hatches and manways, sampling ports, gauge wells, caps, hatches, lids, plugs, seals, valves, or other types of fittings that prevent or reduce air pollutant emissions to the atmosphere by blocking an opening in a cover when the device is secured in the closed position) shall be designed and operated with no detectable leaks as indicated by an instrument reading of less than 500 parts per million above background. You shall demonstrate no detectable leaks for these components measured initially and annually by the following procedures: (1) Method 21, of part 60, appendix A-7; and (2) The instrument specified in Method 21 shall be calibrated before use according to the procedures specified in Method 21 on each day that leak checks are performed. The following calibration gases shall be used: (i) Zero air (less than 10 parts per million by volume of hydrocarbon in air); and (ii) A mixture of methane and air at a concentration of approximately, but less than, 500 parts per million by volume methane.
The Working Group previously recommended clarifying changes to the language in Section 63.11915 in our April 5, 2013 letter to resolve textual uncertainties on the application of the Subpart UU LDAR requirements to pumps, compressors, agitators, and other equipment. As noted above, because Section 63.11915 also includes the requirements for PRDs, another issue in the petition for reconsideration, the Working Group’s suggested changes for all of these issues are also submitted in a single proposal for revisions to Section 63.11915, Attachment VI to this letter. The revisions also include changes to Section 63.11915(c)(2) to address the changes to the definition of the CVS to address bypasses and emission profiles, as suggested in Section IV of this letter. The provision for pressure vessel closure devices would form a new paragraph (d) in Section 63.11915.

IX. Vapor Balancing
Vapor balancing is a widely used and proven control technology that is fundamental to avoiding emissions during normal operations, such as railcar loading.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 63 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Vapor balancing is not addressed in the final PVC MACT rule; nor is it prohibited by the final rule, because no emissions are released from the practice. Nevertheless, both industry and the Agency would benefit from a common and consistent understanding of the practice through explicit regulatory recognition. In addition, its widespread use throughout the industry would make compliance and enforcement of vapor balancing as a Section 63.6(g) alternative means of emission limitation impracticable. Consequently, the Working Group’s petition for reconsideration requested that the Agency grant reconsideration on this issue and include an explicit allowance for vapor balancing in the PVC MACT.
Vapor balancing is used throughout the PVC industry to load storage vessels and unload transportation vehicles ( e.g. , railcars). As the Working Group indicated in our petition for reconsideration, eleven out of seventeen PVC facilities surveyed reported the use of vapor balancing in normal operations. 64 Indeed, it is virtually impossible to unload a vinyl chloride railcar without any HAP emissions unless vapor balancing is used. When unloading a vinyl chloride railcar, there are two options for loading a storage vessel: (1) use vinyl chloride pressure to push vinyl chloride into the storage sphere and vapor balance the sphere back to the railcar; or (2) use nitrogen pressure to push vinyl chloride to the storage sphere and send the vapors to the control device. The second option results in low-level HAP emissions through the control device. In contrast, when using vapor balancing, vapors from the railcar, the sphere, and the lines are recovered, thus ensuring there are no HAP emissions from the process. Thus, vapor balancing is a proven control technology that reduces overall HAP emissions.
In addition, the Agency has allowed vapor balancing as a control option for storage tanks in many other MACT rules, including the Gasoline Distribution MACT, the HON, and the Uniform Standards for Storage Vessels. 65 Based on discussions with Agency staff, it appears that a provision allowing for vapor balancing by PVC facilities was unintentionally omitted from the PVC MACT final rule. Agency staff also indicated that the Agency intended to correct this omission in the reconsidered rule. The Working Group recommends that the following language, which is similar to that previously proposed in the Working Group’s comments and is based on 40 C.F.R. § 63.2346(a)(4), is added to a new paragraph (d) in Section 63.11910 to make it clear that vapor balancing is permitted: (d) Storage vessels may use a vapor balancing system that complies with the requirements specified in paragraphs (d)(1) through (5) of this section and with the recordkeeping requirements specified in § 63.11990. (1) The vapor balancing system must be designed and operated to route organic HAP vapors displaced from loading of the storage vessel to the transport vehicle from which the storage vessel is filled.

64 Petition for Reconsideration at 39.

65 40 C.F.R. Part 63, Subparts R, BBBBBB, and CCCCCC; 40 C.F.R. Part 63, Subparts F, G, H, and I; 77 Fed. Reg. 36,248 (June 18, 2012).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 64 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com (2) Transport vehicles must have a current certification in accordance with the United States Department of Transportation (U.S. DOT) pressure test requirements of 49 CFR part 180 for cargo tanks and 49 CFR 173.31 for tank cars. (3) Organic liquids must only be unloaded from cargo tanks or tank cars when vapor collection systems are connected to the storage vessel’s vapor collection system. (4) No pressure relief device on the storage vessel, or on the cargo tank or tank car, shall open during loading or as a result of diurnal temperature changes (breathing losses). (5) Pressure relief devices installed on fixed roof, internal floating roof, or external floating roof storage vessels must be set to no less than 2.5 pounds per square inch gauge (psig) at all times to prevent breathing losses. Pressure relief devices may be set at values less than 2.5 psig if the owner or operator provides rationale in the notification of compliance status report explaining why the alternative value is sufficient to prevent breathing losses at all times. The owner or operator shall comply with paragraphs (d)(5)(i) through (iii) of this section for each pressure relief valve installed on fixed roof, internal floating roof, or external floating roof storage vessels. (i) The pressure relief valve shall be monitored quarterly using the method described in § 63.1023(b). (ii) An instrument reading of 500 parts per million by volume (ppmv) or greater defines a leak. (iii) When a leak is detected, it shall be repaired as soon as practicable, but no later than 5 days after it is detected, and the owner or operator shall comply with the recordkeeping requirements of § 63.11990(c).

X. Issues Raised by the Other Petitioners
The Working Group also wishes to express its support for certain Agency approaches that may have been challenged in a petition for review or reconsideration filed by other stakeholders.
A. Organic HAP Emission Limits The final PVC MACT sets several emission limits using surrogate pollutants for listed HAPs. The D.C. Circuit has held that the Agency may use surrogates when it is “reasonable” to do so, which is determined by the three-part test first stated in National Lime Association v. EPA

, 66 and more clearly articulated in Sierra Club v. EPA

. 67 Specifically, (1) the target HAP at issue is “invariably” present in the surrogate; (2) the

66 National Lime Association v. EPA , 233 F.3d 625, 639 (D.C. Cir. 2000).

67 Sierra Club v. EPA , 353 F.3d 976, 984 (D.C. Cir. 2004).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 65 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com methods to control the surrogate indiscriminately control the target HAP; and (3) the methods used to control the surrogate are the only means to achieve reductions of the target HAP. 68 This approach was also accepted in the previous PVC MACT case, Mossville v. EPA

. 69

The Agency used three surrogates in the PVC MACT: THC for organic HAPs in process vent emissions, HCl for chlorine in process vent emissions, and total non-vinyl chloride organic HAP for organic HAPs in stripped resin and wastewater. Environmental petitioners have objected to the Agency’s use of total HAP as a surrogate for individual organic HAPs. 70 Although the objecting comments are not entirely clear, this point could reasonably encompass both the use of total non-vinyl chloride organic HAP for stripped resin and wastewater, and the THC/TOHAP compliance alternative provided for process vents.
For process vents, EPA set a “limit on THC as a surrogate for organic HAP emissions from process vents.” 71 The Working Group believes that the use of THC as a surrogate for organic HAPs in process vents meets the three-part test from Sierra Club

, as the Agency explained in the final rule. 72 Specifically, (1) individual organic HAP from PVC process vents are “invariably” present in THC, because the organic HAP emitted from process vents are comprised of hydrocarbons, which are measured as THC; (2) the thermal oxidizers used to control THC indiscriminately control individual organic HAP; and (3) these methods for controlling THC ( i.e. , the recovery system and thermal oxidizers) are the only means to achieve reductions of individual organic HAP from process vents. Furthermore, the D.C. Circuit has implicitly accepted that THC is a surrogate for organic HAP, remanding the Portland Cement MACT in National Lime II to EPA to set an emission limit for THC. 73

For stripped resin and wastewater, EPA set a limit for total non-vinyl chloride organic HAP. Total non-vinyl chloride organic HAP is a reasonable surrogate for the individual organic HAP because: (1) individual organic HAP are by definition invariably present in total non-vinyl organic HAP; (2) the resin strippers and wastewater strippers used to control total non-VC organic HAP indiscriminately control individual insoluble organic HAP and to some extent soluble organic HAP; and (3) resin strippers and wastewater strippers are the only means that PVC-affected sources use to control organic HAP.

68 Sierra Club, 353 F.3d at 984.

69 Mossville, 370 F.3d at 1242-43.

70 The environmental petitioners did not specifically raise the use of HCl as a surrogate for chlorine with reasonable specificity during the period for public comment on the proposed PVC MACT, and have not demonstrated that it was impracticable to raise the issue at that time or that the issue arose after the comment period. This issue is therefore waived. 42 U.S.C. § 7607(d)(7)(B).

71 77 Fed. Reg. at 22,866.

72 Id

. 73 National Lime , 233 F.3d at 634.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 66 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com The use of these surrogates is particularly appropriate in light of the significant product variability in the PVC industry. The variety of resin recipes and products manufactured by PVC MACT affected sources, which require significant variations in ingredients, as well as process parameters, make the use of TOHAP and similar surrogates the only workable solution. 74 The D.C. Circuit has already addressed and accepted a similar situation in the Primary Copper Smelter MACT, where EPA used particulate matter (“PM”) as a surrogate for metal HAPs. There, the D.C. Circuit found that “EPA reasonably articulated its decision to use PM as a surrogate,” based on the Agency’s explanation of the inherent variability in the raw material used in copper smelters: EPA explained that a surrogate was needed in light of the impracticality of setting individual standards for each metal, due to the variability of HAPs in copper ore stocks: Th[e] inherent variability and unpredictability of the metal HAP compositions and amounts in copper ore concentrates affect the composition and amount of HAP metals in the process off-gas emissions. As a result, prescribing individual numerical emission limits for each HAP species (e.g., a specific emission limit for arsenic, a specific emission limit for lead, etc.) is impracticable, if not impossible, to do. Given that prescribing individual numerical emission limits for HAP metal is not a practicable approach in this case, an alternative approach is to use particulate matter as a surrogate pollutant for the metal HAP emitted from primary copper smelters. 75

As in the Primary Copper Smelter MACT, the inherent variability of HAPs used to manufacture the variety of resins in the industry makes it “impracticable, if not impossible” to set individual organic HAP limits. Thus, no alternatives to the TOHAP surrogate approach ( i.e. , other surrogates or individual limits) are available to the Agency. Moreover, because the different resin recipes require different material inputs and different process conditions, the control technologies identified for control of the surrogates are the only means to achieve reductions of the individual organic HAP. For these reasons, the Agency set reasonable surrogates for PVC and copolymer HAPs.
B. EPA’s Methodology in Promulgating the PVC NESHAP for Area Sources on April 17, 2012 is Consistent With the CAA EPA listed PVC and copolymers production area sources pursuant to CAA § 112(c)(3) on June 26, 1992, as a source category separate from the PVC and

74 As the Working Group has stated often, different resin recipes use widely varying ingredients, with corresponding changes in the HAP profile. Moreover, individual resin recipes normally include different reactor temperature profiles, reactor pressure, and other process changes, which impact the HAP emissions produced. The slurry stripper operating parameters are also usually different for different products, including residence time/slurry feed rate, steam feed rate, temperature at various column locations, pressure/vacuum, etc.

75 S ierra Club, 353 F.3d at 986 (internal citations omitted).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 67 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com copolymers major source category, which was listed on June 1, 1992. 76 EPA continued to separate the two categories in subsequent rulemakings. In 2007, EPA promulgated a NESHAP for PVC area sources, separate from the NESHAP for major sources originally promulgated in 2002. 77 When EPA revised the major source standard in 2011, pursuant to CAA § 112(d)(6), the Agency continued to separate major sources from area sources. 76 Fed. Reg. 29,528. In response to comments on the proposal, EPA noted that it is authorized to “promulgate standards or requirements for area sources ‘which provide for the use of generally available control technologies or management practices [GACT] by such sources to reduce emissions of hazardous air pollutants.’” 78

Also, as EPA noted, the Agency’s approach is supported by the legislative history of the CAA Amendments. Congress contemplated that EPA would consider the cost impact of MACT versus GACT standards on area sources, which are by their nature smaller facilities with fewer resources and lower total emissions, when determining how to best regulate emissions. 79

Against that statutory background, EPA appropriately exercised its discretion to set various PVC and copolymers GACT emission limits that are different from the MACT limits for major sources. Specifically, EPA appropriately looked at the differences in technology between area and major sources, and calculated the costs of additional controls per ton of expected pollutant reduction. 80 Further, EPA’s decision to set GACT emission limits using the same subcategories as used in the MACT standards was consistent with CAA § 112(d)(1), which authorizes EPA to “distinguish among classes, types, and sizes of sources within a category or subcategory in establishing such standards.” 81 Therefore, the Working Group encourages EPA to defend its regulatory distinction between PVC and copolymers major sources and area sources, and to retain the GACT standards for area sources.

1. EPA’s promulgation of the PVC NESHAP for area sources includes some emission limits that are lower than the major source emission limits. EPA’s promulgation of GACT standards for area sources here is environmentally protective; indeed, some GACT limits are lower than the corresponding MACT limits, as shown in green in Tables 17 and 18 , below.

76 See 57 Fed. Reg. 31,576.

77 See 72 Fed. Reg. 2,930 (codified at 40 C.F.R. Part 63, Subpart DDDDDD).

78 77 Fed. Reg. at 22,850.

79 See 77 Fed. Reg. at 22,849-50 (citing S. Rep. No. 101-228, at 171-72).

80 77 Fed. Reg. at 22,888-90.

81 42 U.S.C. § 7412(d)(1).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 68 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Table 17: Comparison of Major and Area Source Process Vent Limits
Parameter GACT Combined* MACT Combined GACT PVC Only** MACT PVC Only

VC 0.56 1.1 5.3 6.0 TOHAPS 29 9.8 140 56 THC 2.3 4.2 46 9.7 DIOXINS 0.076 0.051 0.13 0.038 HCl None 380 None 78

Table 18: Comparison of Major and Area Source Resin and Process Wastewater Limits Source Parameter GACT MACT

Suspension Resin* VCM 36 37 TOHAPS 36 670

Bulk Resin** VCM 7.1 7.1 TOHAPS 170 170

Wastewater VCM 2.1 6.8 TOHAPS 0.018*** 110 * Deer Park ** CertainTeed *** This value was determined to have been from a groundwater remediation stripper that was submitted in error.

2. EPA should have included what the Agency characterizes as “synthetic minor sources” in the MACT floor for area sources, not major sources. EPA included what it called “synthetic minor” sources (sources that would be major sources, but for the use of pollution controls under enforceable permits limiting emissions to levels below major source thresholds) in the major source floor, not the area source floor. That is unlawful.
Section 112(a)(1) of the CAA defines a major source for HAP as “any stationary source or group of stationary sources located within a contiguous area and under common control that emits or has the potential to emit considering controls, in the aggregate, 10 tons per year or more of any hazardous air pollutant or 25 tons per year or more of any combination of hazardous air pollutants.” 42 U.S.C. § 7412(a)(1). The Act further defines an area source as any source that is not a major source. 42 U.S.C. § 7412(a)(2). Accordingly, a source that emits or has the potential to emit less than 10/25 tons—whether it does so “naturally” or “synthetically”—is an area source, plain and simple. The CAA does not define a third category of sources called “synthetic minor” sources and therefore EPA cannot do so. 82

EPA’s inclusion of synthetic minor sources among major sources is also not supported by the legislative history of the CAA. According to Congress, “[t]he determination as to whether a source is a major source as defined in section 112(a)(1) is based on the emissions of hazardous air pollutants from the source after application of installed controls and reflecting the actual operating conditions of the particular

82 Oxy argued in comments on the proposed rule that the treatment of a synthetic minor source as a major source is not supported by the CAA definitions. Occidental Chemical Corporation Comments on Proposed Rule, 76 Fed. Reg. 29,528 at 8-12 (Aug. 2, 2011).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 69 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com source.” S. Rep. No. 101-228, at 151 (emphasis added). This clearly contradicts EPA’s rationale.

EPA, then, cannot consider a source that emits or has the potential to emit less than the statutory threshold of any HAP as a major source, and it was unlawful for EPA to include such a source in its MACT floor calculations for major sources. EPA should instead include synthetic minor sources as area sources.

3. The Working Group does not object to EPA’s inclusion of an HCl limit for process vents in the GACT standard. HCl is not an urban HAP. However, the Working Group recognizes that HCl is a product of the combustion in PVC manufacturing, with its accompanying urban HAPs. We do not contest EPA’s discretion under CAA § 112 to regulate HAPs in addition to urban HAPs from area sources when appropriate. See 76 Fed. Reg. at 29,541; Asphalt Processing and Asphalt Roofing Manufacturing NESHAP, 74 Fed. Reg. 63,236, 63,243. EPA has previously found it appropriate to include non-urban HAP limits in area source rules when those HAPs are controlled by the urban HAP limits. See 74 Fed. Reg. at 63,243 (referring to the chemical manufacturing area source rule and the paint and allied products area source rule). Since HCl is already controlled by scrubbers at PVC area sources, the Working Group does not oppose EPA’s regulation of HCl in these particular circumstances. 83

4. Considerations for Major Sources Also Apply to Area Sources The Working Group wishes to emphasize that the concerns discussed in Section III for PVC-combined process vents apply equally to area sources. The Agency should clarify, as discussed in Section II.B, the application of the HON and the PVC MACT to combined process vents. The Agency should adopt the building block approach, as discussed in Section II.C, for area sources as well.

In addition, as noted in the discussion of the major source wastewaterconcentration limits above, the data EPA used to calculate the 0.018 ppmw limit for nonVC TOHAP were faulty and therefore EPA’s conclusion was faulty. The non-VC TOHAP wastewater concentration limit that represents the generally available, as well as the maximum achievable, control technology is 1,000 ppm, as discussed in Section II.

C. Reasonable Estimates Used to Set the MACT Floors The Agency set the MACT floors in the final rule using two primary methodologies. First, the Agency set some MACT floors using the UPL. The UPL accounts for operational variability ( i.e. , the performance a source actually achieved),

83 For purposes of the reconsidered rule, we note that EPA previously received HCl emissions data on November 9, 2009, generated from OxyVinyls’ process vent stack test conducted at its Deer Park/LaPorte facility, which is a PVC-combined control device. EPA issued an approval letter for this submission on November 24, 2009.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 70 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com which would not otherwise be addressed by the limited data set used to determine the MACT floor. In tandem, the UPL approach includes an assessment of the representative detection limit (“RDL”) when non-detect values are included in the data set. This approach has been used in the Portland Cement MACT and the Boiler MACT. Second, the Agency set the MACT floors for vinyl chloride in stripped resin using a 99 th percentile approach for the top five sources. The percentile approach was used because the data set was sufficiently large (four years), such that it was not necessary to estimate variability using the UPL equation. The percentile approach accounts for operational variability directly from the vinyl chloride data set comprised of the top five

sources.
As we stated above, the requirement of 42 U.S.C. § 7412(d)(3)(B) that EPA must set the MACT floor based on the “average emission limitation achieved by the best performing 5 sources” is generally based on data representing a snapshot in time, but must account for the performance and product variability of PVC facilities over their entire operating life. The Agency’s variability calculations include both operational variability (the UPL) and measurement variability (the RDL). The Working Group questions whether these calculations are always sufficient to fully address the variations in product recipes, discussed throughout this letter, that exist within individual facilities and throughout the industry.
It is worth noting, however, that the D.C. Circuit recognized a non-statistical approach to account for product variability. In Mossville , the court held that variability estimates were appropriate when EPA has “pointed to factual data” that the promulgated standard “reasonably estimates the performance of the top performers, because even the best performing sources occasionally have spikes, and under the standard, each facility must meet the 400 ppm standard every day and under all operating conditions.” 84

The Agency’s authority to use reasonable estimates to set the MACT floor has been acknowledged by the D.C. Circuit on enough occasions that the Working Group believes the use of such estimates is well-settled law. 85 Although the UPL and percentile approaches have not been specifically addressed before the D.C. Circuit, the Agency’s use of these statistical models of emission variability is of the type of technical evaluations of scientific data to which the D.C. Circuit defers. 86 Consequently, the Agency should not abandon its use of these approaches on reconsideration.

84 Mossville, 370 F.3d at 1242.

85 See, e.g.

, National Lime , 233 F.3d at 633; Cement Kiln , 255 F.3d at 861; Mossville , 370 F.3d at 1242.

86 Coalition for Responsible Regulation v. EPA , 684 F.3d 102, 120 (D.C. Cir. 2012) (“[W]e give an extreme degree of deference to the agency when it is evaluating scientific data within its technical expertise.” (quoting Am. Farm Bureau Fed’n v. EPA , 559 F.3d 512, 519 (D.C. Cir. 2009))).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 71 of 71 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com XI. Conclusion
We appreciate the Agency’s consideration of this information. For purposes of logical presentation and thoroughness, we have discussed the various provisions of the rule and the related equipment separately. As we noted in Section I.C, however, each manufacturing facility in the PVC and copolymers source category is an integrated and interdependent sum of these various parts. A holistic view must be maintained in establishing regulatory limits and compliance parameters in order to avoid compromising the integrity of the entire facility.

We recognize that the approaches we have presented will require the Agency’s careful validation and implementation. Given the complexity and scope of the preceding discussion, the Working Group is readily available to provide any needed clarification or assistance in understanding our approach and calculations. The Working Group is confident, however, that the Agency will find our proposed approach to be fully consistent with, and hewing closely to the framework set out in the Clean Air Act.

# ATTACHMENT I

Technical Impacts of PVC MACT Comments on Change in Resin Properties Affecting

Downstream UsersMemorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com 

### I. Types and Grades of PVC Resins Made by U.S. Producers

a. The Vinyl Institute estimates that there are over 100 different types and grades of PVC resins made by U.S. producers affected by the proposed PVC MACT. The chart below developed by the Vinyl Institute depicts the estimated percents of these many and various types, and grades of resins.



### II. ASTM PVC Resin Cell Classifications under D1755

a. All PVC resins made today are graded under ASTM’s cell classification which ranks the properties of the resin by categories of IV, particle size distribution, bulk density, plasticizer absorption, dry flow, and conductivity. (Reference OxyVinyl’s data sheet for Oxy 185 PVC resin attached).

b. Changes in PVC resin polymerization chemistry to achieve lower emissions may affect that resin’s physical properties and could change its cell classification. Certain PVC pipe recipes only allow PVC resin with a specific ASTM D1755 cell classification. If the resin Medium and high molecular weight suspension General Purpose flexible extrusion

grade 9% Low Fusion low molecualar

weight molding suspension

resins 8% Dispersion resins

4% All others, including

speciality blending suspension 5%

Copolymer resins 1% General Purpose Suspension Resin rigid extrusion grade 73% 

### PVC Resin by Resin Type and Resin GradeMemorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com does not have that cell classification, the pipe compound manufacturer cannot use the
resin.


### III. PVC Pipe Industry

a. General purpose extrusion pipe grade PVC suspension resins have unique properties. The resin must have certain impact, dimensional stability, chemical resistance, chemical extraction, tensile strength and modulus across a specified temperature range. Changes in PVC resin polymerization chemistry to achieve lower emissions may affect that resin’s physical properties and could change its cell classification. Certain PVC pipe recipes only allow PVC resin with a specific ASTM D1755 cell classification. If the resin does not have that cell classification, the pipe compound manufacturer cannot use the resin.

b. Changing suspension pipe grade resin physical properties to meet more restrictive emissions standards may require additional investment by the PVC pipe industry. Lower thermal stability resin as a result of stripping that damages the resin will require more heat stabilizer in the downstream pipe compound formulation. Higher porosity resin has a lower bulk density, which means fewer pounds can be processed on the same extrusion line. Lower bulk density resins may require capital investment in additional lines in order to keep pipe output constant at a facility. Lower bulk density resins will also require more resin deliveries as the rail cars will hold fewer pounds per delivery, which further increase the greenhouse gas emissions from transporting the added volume of resin. The Vinyl Institute estimates that the proposed rule will affect approximately 46% of total PVC resin manufactured which is the amount used in pipe applications (reference Vinyl Institute Chart under subheading I above), since there are no producers today that consistently meet EPA’s proposed limit for vinyl chloride on a daily basis for general purpose resins used in pipe applications.

c. The current PVC pipe compound formulations have been refined over many years. Current compound formulations meet many ASTM and NSF standards. NSF National Sanitation Foundation Listings will be affected by any resin changes as a result of new PVC MACT requirements. Under NSF/ANSI Standards 14, 24, 50, 61, and the Mechanical Plumbing Program, NSF provides the plumbing industry testing and product certification services for items such as pipes, fittings, valves, pumps, chemical feeding equipment, water heaters, sinks, showers, toilets, faucets, controllers, filters, materials, and ingredients. NSF conducts testing, listing, certification, as well as enforcement of its trademark. An NSF Listing is evidence that a product meets all requirements of aMemorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com standard or criteria. NSF Certification describes conformity assessment. NSF Certification is the process by which a product or system is confirmed meet the requirements of a standard. NSF evaluates products based on end use and based on standards. Evaluations routinely include health and safety assessment and performance validation of products and materials. Beyond testing, NSF staff members conduct assessments of the quality control and quality assurance systems employed by the production facility. NSF registers a list of materials and suppliers to manufacturers to maintain consistency and ensure quality. NSF also conducts unannounced surveillance inspections at the production site to review materials of use, production process, product quality, and to obtain monitoring (re-testing) samples. Any changes to the PVC resin that might be needed to meet new lower stripped resin emissions may correspondingly cause the users of that resin to reformulate their products. Reformulating products may take months, and then may take one or more years to be relisted at NSF due to their extensive testing on plastic materials for health, safety and performance attributes. NSF periodically and randomly checks materials for their listed “fingerprint” FTIR composition. If a pipe compound recipe is changed to add more heat stabilizer to compensate for reduced thermal stability of the PVC resin as a result of the resin producer needing to strip the resin for longer periods of time, then the recipe must go through the laborious relisting process at NSF laboratories.

d. Performance would not be an issue after reformulation and re-refining of the new formulations, but this will take time and money at a time when the industry has still not fully recovered from the 2008 downturn. PVC resin for pressure pipe takes years to qualify.

e. The following is a partial listing of the number of standards for PVC pipe that will be affected by any resin modifications that are substantial enough to cause compound recipe modifications (reference Uni-Bell Handbook of PVC Pipe, Fourth Addition, November, 2005, pg 87 – 118):

American Association of State Highway and Transportation Officials – 3 standards American National Standards Institute – 9 standards American Society of Agriculture Engineers – 3 standards American Society of Testing and Materials – 62 standards American Water Works Association – 8 standards Bureau de Normalisation du Quebec – 5 standards Canadian Standard Association – 10 standards International Standards Association – 41 standards NSF/ANSI Standards 14, 61Memorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com 

### IV. PVC Pipe Fittings Industry

a. Low molecular weight injection molding grade PVC suspension resins for pipe fittings have unique properties. The resin must have certain impact, dimensional stability, chemical resistance, chemical extraction, tensile strength and modulus across a specified temperature range. Fittings products demand the durability of their original physical properties over the life of their use, typically 50 years or more. Changes in PVC resin polymerization chemistry to achieve lower emissions may affect that resin’s physical properties.

b. Changing suspension fittings grade resin physical properties to meet more restrictive emissions standards may require additional costs and investment by the PVC fittings industry. Higher porosity resin, or conversely resin that has lower thermal stability as a result of stripping that damages the resin, will require reformulation to meet fittings standards now in place.

c. The Vinyl Institute estimates that the proposed rule will affect approximately 7% of total PVC resin manufactured which is the amount used in fittings applications (reference Vinyl Institute Chart under subheading I above) since there are no producers today that consistently meet EPA’s proposed limit for vinyl chloride on a daily basis for low molecular weight molding resins.

d. The current PVC pipe fitting formulations have been refined over many years. Current formulations meet many ASTM and NSF standards. NSF National Sanitation Foundation Listings will be affected by any resin changes as a result of new PVC MACT requirements. Under NSF/ANSI Standards 14, 24, 50, 61, and the Mechanical Plumbing Program, NSF provides the plumbing industry testing and product certification services for items such as pipes, fittings, valves, pumps, chemical feeding equipment, water heaters, sinks, showers, toilets, faucets, controllers, filters, materials, and ingredients. NSF conducts testing, listing, certification, as well as enforcement of its trademark. An NSF Listing is evidence that a product meets all requirements of a standard or criteria. NSF Certification describes conformity assessment. NSF Certification is the process by which a product or system is confirmed meet the requirements of a standard. NSF evaluates products based on end use and based on standards. Evaluations routinely include health and safety assessment and performance validation of products and materials. Beyond testing, NSF staff members conduct assessments of the quality control and quality assurance systems employed by the production facility. NSF registersMemorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com a list of materials and suppliers to manufacturers to maintain consistency and ensure quality. NSF also conducts unannounced surveillance inspections at the production site to review materials of use, production process, product quality, and to obtain monitoring (re-testing) samples. Any changes to the PVC resin that might be needed to meet new lower stripped resin emissions may correspondingly cause the users of that resin to reformulate their products. Reformulating products may take months, and then may take one or more years to be relisted at NSF due to their extensive testing on plastic materials for health, safety and performance attributes. NSF periodically and randomly checks materials for their listed “fingerprint” FTIR composition. If a recipe is changed to add more heat stabilizer to compensate for reduced thermal stability as a result of the resin producer needing to strip the resin for longer periods of time, then the recipe must go through the laborious relisting process at NSF laboratories.

e. Performance would not be an issue after reformulation and re-refining of the new formulations, but this will take time and money at a time when the industry has still not fully recovered from the 2008 downturn. PVC resin for fittings takes years to qualify.

f. The following is a partial listing of the number of standards that will be affected by any resin modifications that are substantial enough to cause compound recipe modifications (reference Uni-Bell Handbook of PVC Pipe, Fourth Addition, November, 2005, pg 121 – 172 and Plastic Pipe and Fittings Association Technical Specifications list, p. 7):

American National Standards Institute and American Water Works Association – Standards ANSI/AWWA C900 and C905 American Society of Testing and Materials (ASTM)– 20 standards Canadian Standard Association – 2 standards NSF/ANSI Standards 14, 24, 61



### V. Electrical Devices and Electronic Products

a. Low molecular weight suspension grade resins are used in injection molding compounds for electrical wiring devices, outlet and ceiling boxes, electrical conduit fittings and connectors, and electronic enclosure products. These resins are of a high flow nature to be able to fill injection molding tools easily and quickly without thermally degrading. The resins are designed to meet tight dimensional tolerances, long term retention of impact, and in some applications tight color specifications.Memorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com b. Underwriter Laboratory yellow card listings study electrical and mechanical properties of plastic materials under UL Standard 746. Any recipe change in the compound must be relisted at UL, which in some cases takes years to obtain. UL performs a relative thermal index on plastic compounds, which is an estimation of the retention of original notched izod impact of a plastic material after 10 years of service. To obtain the estimate, UL subjects samples of the test materials in their laboratories to elevated temperatures for 10,000 hours, which is 417 days. The amount of retained impact determines that material’s relative thermal impact (RTI). Once listed, an FTIR “fingerprint” of the material is recorded. Period inspections on users of that material must have the identical FTIR fingerprint.

c. Changes in resin in order to meet new PVC MACT emissions requirements may require recertification of injection molding compounds for electrical wiring devices, outlet and ceiling boxes, and electronic enclosure products. In some instances, reformulating compounds may not be technically feasible to compensate for substantial changes in the resin due to excessive steam stripping. If more stabilizer is added to the compound to make up for a thermally degraded resin, then other properties of the compound could suffer, such as its hardness at elevated temperature, tensile strength and
modulus.

d. The Vinyl Institute estimates that the proposed rule will affect approximately 1% to 2% of total PVC resin manufactured which is the amount used in electrical device and enclosure applications (reference Vinyl Institute Chart under subheading I above) since there are no producers today that consistently meet EPA’s proposed limit for vinyl chloride on a daily basis for low molecular weight molding resins.

e. Performance would not be an issue after reformulation and re-refining of the new formulations, but this will take time and money at a time when the industry has still not fully recovered from the 2008 downturn. PVC resin for electrical applications takes years to qualify.

f. The following is a partial listing of the number of standards for electrical fittings and enclosures that will be affected by any resin modifications that are substantial enough to cause compound recipe modifications (reference Uni-Bell Handbook of PVC Pipe, Fourth Addition, November, 2005, pg 87 – 118):Memorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com Underwriters Laboratories – 7 standards: UL 746C, -514B,C,D, -1285, -5A, -209, -486C, - 489, -498A, -20, and -98. Canadian Standards Association – C22.2 No. 85 National Electrical Manufacturers Association – 3 standards: TC 3, - 9, and -10.



### VI. Electrical Conduit

a. Suspension grade general purpose PVC resins are used in electrical and telecommunications conduit and nonmetallic tubing. Extruded conduits demand resins with high impact, dimensional stability, and high tensile strength and modulus, all at a low cost. Underwriter Laboratory yellow card listings study electrical and mechanical properties of plastic materials under UL Standard 746. Any recipe change in the compound must be relisted at UL, which adds costs to the manufacturer of these products.

b. Changes in resin in order to meet new PVC MACT emissions requirements may require reformulation of extrusion compounds for electrical conduit and nonmetallic tubing used in commercial, industrial and residential wiring installations. If more stabilizer is added to the compound to make up for a thermally degraded resin, then other properties of the compound will suffer, such as its hardness at elevated temperature, tensile strength and modulus.

c. The Vinyl Institute estimates that the proposed rule will affect approximately 3% to 4% of total suspension general purpose PVC resin manufactured which is the amount used in extruded conduit applications (reference Vinyl Institute Chart under subheading I above) since there are no producers today that consistently meet EPA’s proposed limit for vinyl chloride on a daily basis for general purpose extrusion resins used in conduit applications.

d. Performance would not be an issue after reformulation and re-refining of the new formulations, but this will take time and money at a time when the industry has still not fully recovered from the 2008 downturn.

e. The following is a partial listing of the number of standards for electrical and telecommunications conduit that will be affected by any resin modifications that areMemorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com substantial enough to cause compound recipe modifications (reference Uni-Bell Handbook of PVC Pipe, Fourth Addition, November, 2005, pg 87 – 118):

Underwriters Laboratories – 7 standards: UL 746C, -651,-651A,-1285, -1653, and -1660 Canadian Standards Association – 5 standards B196.3, C22.2 No. 211.0, -211.1, -211.2, and -227.1 National Electrical Manufacturers Association – 8 standards: TC 2, 6, 8, 10, 12, 13, 15, and 18. ASTM American Society of Testing and Materials (ASTM)– 1 standard - F512

VII. 

### Vinyl Siding

a. Special siding grade resins categorized under general purpose suspension resins are produced for vinyl siding manufacturers to have the right impact, flow, color, and tensile strength and modulus. Siding is made on high speed lines that require a high flow compound to fill the die, yet higher resin IV for impact. Tight color control for siding resins is an imperative quality, not just for uniform color matching across the side of a residence, but for long term weatherability and color retention. Siding is warranted by most manufacturers for 50 years or longer and must retain certain physical properties for the length of the warranty.

b. Building codes established in 2006 by the International Code Council (ICC) require all vinyl siding to be certified and labeled by an approved quality control agency to show it conforms to ASTM D3679. Federal, state and local building code entities throughout the United States are adopting the 2006 ICC model codes.

c. Since 1998, vinyl siding products certified through the VSI Vinyl Siding Product Certification Program are verified by an accredited inspection agency, Architectural Testing, Inc. (ATI) of York, Pennsylvania. ATI conducts two unannounced inspections at each plant every year, reviews quality test data, pulls siding right off the production line and conducts performance tests in its accredited laboratory to ensure that vinyl siding meets or exceeds ASTM D3679, the standard for quality. The credibility of the ASTM standard, combined with this third-party verification, gives added confidence to vinyl siding purchasers and sets vinyl siding apart from other exterior cladding products. ASTM D3679 includes tests for weatherability, windload, impact resistance and heat shrinkage, among others.Memorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com d. Changes to the PVC resin suspension manufacturing process may cause the physical properties of the resin to change. A small change in thermal stability, porosity, particle size, or particle size distribution could have a significant effect on the ability to process the resin on a siding extrusion line, the rates of processing, and could affect properties controlled by ASTM D3679 such as impact, shrinkage, weatherability, and tensile strength and modulus. The Vinyl Institute estimates that the proposed rule will affect approximately 15% of total PVC resin manufactured which is the amount used in siding applications (reference Vinyl Institute Chart under subheading I above), since there are no producers today that consistently meet EPA’s proposed limit for vinyl chloride on a daily basis for general purpose resins used in siding applications.

e. Performance would not be an issue after reformulation and re-refining of the new formulations, but this will take time and money at a time when the industry has still not fully recovered from the 2008 downturn.

VIII. 

### Vinyl Windows

a. Certain general purpose suspension grade extrusion resin products are specifically tailored for use in window profiles. Window profile compounds must meet stringent impact and color retention requirements, tight profile dimensional tolerances, and thermal dimensional stability. The properties must be durable for the life of the product, which is typically 20 years or longer.

b. To be deemed as conforming to AAMA/WDMA/CSA 101/I.S.2/A440 and therefore certifiable under the AAMA Certification Program, windows made of polymeric (vinyl, fiberglass, ABS, composite) sash and frame materials must be made from profiles that comply with applicable AAMA specifications for those materials, namely AAMA 303-08 Voluntary Specification for Rigid Poly (Vinyl Chloride) (PVC) Exterior Profiles and AAMA 308-05 Voluntary Specification for Cellular Poly Vinyl Chloride (PVC) Exterior Profiles.

c. Profiles must be certified for compliance through the AAMA Profile Certification Program in which randomly-selected production line samples of extrusions are tested by an accredited third-party laboratory for conformance with the appropriate AAMA profile specification using ASTM test method D4726-02, D4803, and AAMA 303 Sec. 4.4.2. The requirements include impact resistance, dimensional stability, heatMemorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com resistance, weight tolerance, and color retention as determined from years of actual outdoor weathering tests.

d. The profile producer must also prepare a Quality Control Manual setting forth the procedures used to assure ongoing conformance of the product with the AAMA specifications. At least two unannounced in-plant inspections are conducted annually by third-party inspectors to determine continued compliance with the program.

e. Changes to the PVC resin suspension manufacturing process may cause the physical properties of the resin to change. A small change in resin thermal stability, porosity, particle size, or particle size distribution could have a significant effect on the ability to use the resin in the same compound formulation or process the resulting material on a window profile extrusion line. Window profile properties controlled by AAMA/WDMA/CSA 101/I.S.2/A440 such as impact, dimensional stability, weatherability, and heat resistance for each compound will have to reassessed, and those that are deficient will have to be reformulated to be acceptable. In some cases extrusion tooling may need to be retuned or re-cut to produce the correct dimensions for any new formulation, each at considerable cost to the processor. The Vinyl Institute estimates that the proposed rule will affect approximately 5% of total PVC resin manufactured which is the amount used in window profile applications (reference Vinyl Institute Chart under subheading I above), since there are no producers today that consistently meet EPA’s proposed limit for vinyl chloride on a daily basis for general purpose resins used in window profile applications.



### IX. Resilient Floor Coverings

a. Dispersion, specialty blending, and copolymer resin products are specifically tailored for use in resilient floor coverings. Floor covering, carpet backing, and adhesives formulations must meet stringent plastisol viscosity, fusion, volatiles, hardness and wear, clarity, stain resistance, thermal stability, and dimensional stability requirements. The properties must be durable for the life of the product, which is typically 20 years or longer.

b. Changes to the PVC resin dispersion, suspension blending, and copolymer manufacturing process may cause the physical properties of the resin to change. AMemorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com small change in thermal stability, plastisol viscosity, particle size, particle size distribution could have a significant effect on the ability to process the resin on a resilient floor covering extrusion line or the ability to laminate onto carpet backing, the rates of processing in addition to meeting the 15 ISO and 42 ASTM standards that floor coverings are manufactured to comply with. The Vinyl Institute estimates that the proposed rule will affect all dispersion, suspension blending, and copolymer resins, which comprise approximately 10% of total PVC resin manufactured overall (reference Vinyl Institute Chart under subheading I above), whose primary use in floor covering applications will be jeopardized since there are no producers today that meet EPA’s proposed limit for vinyl chloride on a daily basis for these types of resins.

c. Members of the Resilient Floor Covering Institute (RFCI) participate in the development of ISO Standards for resilient floor covering since 2001. The purpose of these ISO resilient flooring standards is to establish standards which are accepted worldwide. There are several types of standards. The standards which ISO Technical Committee #219 (Carpet, Resilient & Laminate flooring) has been developing are primarily test method standards and product specification standards. Technical Committee #219, Working Group 2 (Resilient Flooring) has developed the partial list of standards shown below. Additional standards are in the process of being developed. ISO 4918:2009 -Resilient, textile and laminate floor coverings -- Castor chair test ISO 10874:2009 - Resilient, textile and laminate floor coverings -- Classification ISO 10874:2009 - Resilient floor coverings -- Determination of density ISO 23997:2007Resilient floor coverings -- Determination of mass per unit area ISO 23999:2008 - Resilient floor coverings -- Determination of dimensional stability and curling after exposure to heat ISO 24340:2006 - Resilient floor coverings -- Determination of thickness of layers ISO 24341:2006 - Resilient and textile floor coverings -- Determination of length, width and straightness of sheet ISO 4342:2007 - Resilient and textile floor-coverings -- Determination of side length, edge straightness and squareness of tiles ISO 24343-1:2007 - Resilient and laminate floor coverings -- Determination of indentation and residual indentation -- Part 1: Residual indentation heat ISO 24344:2008 - Resilient floor coverings -- Determination of flexibility and deflection ISO 24345:2006 - Resilient floor coverings -- Determination of peel resistance ISO 24346:2006 - Resilient floor coverings -- Determination of overall thicknessMemorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com ISO 26987:2008 - Resilient floor coverings -- Determination of staining and resistance to chemicals d. ASTM Committee F06 on Resilient Floor Coverings has jurisdiction of over 42 standards, published in the Annual Book of ASTM Standards, Volume 15.04. F06 has 6 technical subcommittees that maintain jurisdiction over these standards. Information on this subcommittee structure and F06's portfolio of approved standards and Work Items under construction are available from the Lists of Subcommittees, Standards and Work Items at ASTM. These standards have and continue to play a preeminent role in all aspects important to the industry of resilient floor coverings and related products.



### X. Wallcoverings

a. Certain dispersion resin products are specifically tailored for use in wallcoverings. Wallcovering formulations must meet stringent plastisol viscosity, fusion, volatiles, tear resistance, stain resistance, scrubbability, color retention, and shrinkage requirements. The properties must be durable for the life of the product, which is typically 20 years or longer.

b. Changes to the PVC resin dispersion manufacturing process may cause the physical properties of the resin to change. For example, a small change in thermal stability, plastisol viscosity, particle size, or particle size distribution could have a significant effect on the ability to process the resin on a wallcovering extrusion or coating line or the ability to laminate various constructions, and the rates of processing in addition to meeting W-101 standard that wallcoverings are manufactured to comply with. The Vinyl Institute estimates that the proposed rule will affect all dispersion resin, which comprise approximately 1% of total PVC resin manufactured overall (reference Vinyl Institute Chart under subheading I above), whose primary use in wallcovering applications will be jeopardized since there are no producers today that meet EPA’s proposed limit for vinyl chloride on a daily basis for this type of resin.

c. The Wallcoverings Association (WA) recently announced the release of W-101, WA Quality Standard for Polymer Coated Fabric Wallcovering. This standard is designed to ensure a consistent performance and quality for all polymer coated fabric wallcoverings in a wide variety of settings. The new WA standard covers such attributes as weight,Memorandum to EPA Docket ID No. EPA-HQ-OAR-2002-0037

76 Fed. Reg. 29,528 (May 20, 2011)

1737 King Street, Suite 390 ● Alexandria, VA 22314 ●(571) 970-3359 ● Fax (571) 970-3271

www.vinylinfo.org ● www.vinylindesign.com physical strength, tear properties, flammability, UV fade resistance, stain resistance, and scrubbability.

Sincerely,

Richard P. Krock Technical Director e-mail: rkrock@vinylinfo.org phone: 571-970-3392 cell: 571-216-4474

# ATTACHMENT II

VI Aggregated PVC MACT S114 WW Data (see separate Excel file included)

# ATTACHMENT III

Emissions of High-Solubility VOCs fromMunicipal Sewers, Report for TischlerKocurek and The Pharmaceutical Research and Manufacturers of America (1996)

# ATTACHMENT IV

EPA Guidance on Denitrification

and Clifton T. Jackson, Methanol, Denitrification and Safety, Water Env. & Tech pp. 53-54

(July 2013)

# Wastewater Management Fact Sheet

1 

## Denitrifying Filters

INTRODUCTION Discharge permits for treated wastewater from publicly owned treatment works (POTWs) often include effluent limitations for nutrients. Total maximum daily loads (TMDLs) for nutrients are being developed for many waterbodies throughout the United States. TMDLs and other water quality-drivers have resulted in POTWs having to comply with more stringent effluent limitations for parameters such as total nitrogen (TN).

Untreated domestic wastewater contains ammonia. Nitrification is a biological process that converts ammonia to nitrite and nitrite to nitrate. If standards require that the resulting nitrate be removed, one treatment alternative is the process of denitrification, in which nitrate is reduced to nitrogen gas. One treatment system used for denitrifying wastewater effluent is the denitrifying filter. In addition to the reduction of total nitrogen, this treatment process removes suspended solids from the effluent.



### NITRIFICATION

### /D ENITRIFICATION Nitrificationis a microbial process by which ammonia is sequentially oxidized to nitrite and then to nitrate. The nitrification process is accomplished primarily by two groups of autotrophic nitrifying bacteria that can build organic molecules by us ing energy obtained from inorganic sources––in this case, ammonia or nitrite.
In the first step of nitrification, ammoniaoxidizing bacteria oxidize ammonia to nitrite according to equation (1):

NH 3+ O 2 Æ NO 2–+ 3H ++ 2e

–(1)

Nitrosomonas is the most frequently identified genus associated with this step, although other genera, including Nitrosococcus and Nitrosospira , may be involved. The subgenera Nitrosolobus and Nitrosovibrio can also autotrophically oxidize ammonia.
In the second step of the process, nitriteoxidizing bacteria oxidize nitrite to nitrate according to equation (2):

NO 2–+ H2O → NO3

–+ 2H ++2e

– (2)

Nitrobacter is the genus most frequently associated with this second step, although other genera, such as Nitrospina
, Nitrococcus , and Nitrospira , can also autotrophically oxidize nitrite (U.S. EPA, Nitrification, August 2002).
Denitrification is the process by which nitrates are reduced to gaseous nitrogen by facultative anaerobes. Facultative an aerobes, such as fungi, can flourish in anoxic conditions because they break down oxygen containing compounds (e.g., NO 3 - ) to obtain oxygen. Once introduced into the aquatic environment, nitrogen can exist in several forms—dissolved nitrogen gas (N2), ammonia (NH4 +and NH 3 ), nitrite (NO 2 - ), nitrate (NO 3 - ), and organic nitrogen as proteinaceous matter or in dissolved or particulate phases. The energy reactions are (Metcalf and Eddy, 1979):

6 NO 3 -+ 2 CH 3 OH Æ 6 NO 2 -+ 2 CO 2+ 4 H 2O (Step 1)

6 NO2-+ 3 CH3OH Æ 3 N2 + 3 CO2 + 3 H2O +6 OH- (Step 2)
Overall,

6 NO 3 -+ 5 CH 3 OH Æ 5 CO 2+ 3 N2+ 7 H 2O + 6 OH The organisms carrying out this process are called denitrifiers . In general, they are heterotrophic bacteria that metabolize readily biodegradable substrate under anoxic conditions using nitrate as the el ectron acceptor. If oxygen is available, these bacteria use it for metabolism before they use the nitrate. Therefore, dissolved oxygen concentrations must be minimized for the denitrification process to function2 efficiently. Oxygen is typically m avoiding aeration of the

demand (BOD) so that the m all the oxygen.
A readily biodegradable carbon source) mu denitrifiers to use. denitrifying filter instal aerobic treatment, in which m

e

ce is readily

URES

nable them to reuse treated wastewater to augment

e aquifers (Figures 1 and o remove

ntinuous-backwash filters differ in

bed. Filtered water rises through a separator that removes the light dirt particles by washing them away and returns the large, heavy sand grains to inimized by wastewater and having a high concentration of biochemical oxygen icroorganisms use

organic compound (a st be available for the Because the typical

lation is downstream of ost of the organic
st material is oxidized, some organic material mu be added to the filter influent to sustain th growth of the denitrifiers. The carbon sour most often selected is methanol, which degraded under anoxicand aerobic conditions. Other carbon sources, such as acetic acid, also can be used in denitrifying filter systems.



### D ESIGN 

### F EAT Filter Configurations Denitrifying filters have been utilized for wastewater treatment for a number of years. The combination of denitrification and solids removal was first patented in the 1970s. Since that time, several companies have developed their own denitrifying filters. In addition to meeting TMDL requirement s, facilities such as the East Central Regional Water Reclamation Facility in West Palm Beach, Florida, are utilizing denitrification filters as part of an advanced wastewater treatment system to e

wetlands and to recharg 2).
There are two main process configurations for denitrification filters commercially available, downflow and upflow continuous backwash filters.
Downflow denitrification filters operate in a conventional filtration mode and consist of media and support gravel supported by an underdrain. Manufacturers include Severn Trent Services (Fort Washington, Pa.), maker of the TETRA Denite system; F.B. Leopold Co. Inc. (Zelienople, Pa.), maker of the elimi-NITE system; and Siemens Water Technology Davco Products (Thomasville, Ga.), maker of the Davco denitrification filter.

Wastewater enters a downflow filter over weirs along the length of the f ilter bed on both sides. Filter effluent is conveyed from the bottom of the filter over a control weir into a clear well. Backwashing is required at regular intervals. Backwashing typically involves air scouring and backwashing with air and water. During the process, nitrate is metabolized to nitrogen gas, which becomes embedded in the filter media. Nitrogen-release cycles are needed t these nitrogen gas bubbles that accumulate. The piping for the filter influent and backwash is similar to that of conventional filters.
Upflow co that influent wastewater flows upward through the filter, countercurrent to the movement of the sand bed.

Wastewater enters the filter through the influent pipe (where methanol can be added), and then is transported downward through a supply pipe and distributors (Figure 3). The water moves up through the filter media and filtrate is discharged from the upper portion of the filter. The filter media travels slowly downward and is drawn into an airlift pipe in the center of the filter. Compressed air is introduced to the airlift, drawing sand upward and scouring it. At the top of the airlift, the media isreturned to the filter Figures 1 and 2. Denitrifying filters at the East Central Regional Water Reclamation Facility, West Palm Beach, Florida3 Figure 3. Astrasa nd upflow continuousbackwash filter.

g

pply this filter in the United States and Canada.

h and filter control, and methanol feed control. entrainment over the influent weir is less an issue for those tilizing this configuration.

naSand and Astrasand filters that utilize the upflow ckwash filter design. the top of the filter bed. The reject, or backwash, water continuously exits near the top of the filter. The reject-water weir is set at a lower elevation than the effluent weir to allow clean water to enter the washer and separator continuously by differential head, eliminatin the need for typical backwash-supply pumps.
Manufacturers include Parkson Corp. (Fort Lauderdale, Fla.), maker of the DynaSand filter, and Paques bv (Balk, Netherlands), maker of the Astrasand filter. Siemens Water Technologies has a license agreement with Paques to su

Filter Design Characteristics When designing a denitrif ication filter, there are many considerations that should be taken into account by wastewater professionals. Table 1 presents a brief overview of the systems offered by different manufacturer s (deBarbadillo et al. 2005). Major design considerations include 1) a manufacturer’s experience and 2) the system’s performance, which includes influent weir configuration, types of f ilter media, underdrain, process controls such as backwas

Filter Influent Weirs Many downflow denitrification filters are capable of being operated at variable levels and may have a significant drop over the influent weir. This drop can result in the entrainment of dissolved oxygen (DO). The increase in DO reduces the efficiency with which the filter removes nitrate and increases methanol consumption. In order to address this issue, manufacturers have developed different designs to mitigate the problem. The TETRA Denite system has a patented curvilinear weir block to encourage laminar flow down the wall to minimize DO entrainment. The elimi-NITE system can also be installed with a curved stainless steel weir to solve this problem. Additionally, the F.B. Leopold Company has suggested that operating the system in a constant-level mode would reduce the elevation drop from the influent weir, thereby decreasing the level of DO entrainment. Since influent in upflow continuous-backwash filters is conveyed to the feed radials withinthe filter bed through submerged manifold piping, DO

filters u

Media The preferred media for each filter manufacturer is also presented in Table 1. The filter media in the TETRA Denite system consists of a monomedia granular sand with a two to three millimeter effective size. Uniform and relatively spherical media reportedly allow for more rolling and contact with other media grains, resulting in more effective backwash and nitrogen-release cycles and, ultimately, lower backwash water volume requirements. Davco filters can be supplied with the same media. Finer media are used with the Dy

continuous-ba

Underdrain Early experience with downflow denitrification filters suggested that nozzle underdrains were prone to fouling and failure. To avoid these problems, manufacturers have developed unique block underdrains (Figure 4) (deBarbadillo et al. 2005). Severn Trent Services offers the TETRA T-block underdrain, which is specifically designed for bioreactor service and consists of concrete-filled blocks enclosed in high-density4 Figure 4. Block Underdrain Systems.

new installations will be supplied with the Multiblock HDPE underdrain. Upflow ers do not require an

operate in the same direction that the nitrogen gas travel s, and the gas also is assing cycle sh cycle.

ou s-backwash stream. A

biomass for denitrification.

ging the bed turnover rate in might be necessary to polyethylene (HDPE). F.B. Leopold developed its Universal Type S underdrain, which consists of HDPE blocks. Although existing Davco filters were constructed with pipe lateral underdrains,

continuous-backwash filt underdrain.

Nitrogen Release Cycle During the denitrification reaction, nitrogen gas accumulates in the media bed. Wastewater is forced to flow around the gas and increases head loss in the filter. The nitrogen release cycle emits the nitrogen gas into the atmosphere. The TETRA Denite system offers a control package, known as SpeedBump, which pumps backwash water up through the filter for 30 seconds to 2 minutes. The influent valve to the filter remainsopen to minimize filter downtime. The elimiNITE and Davco systems offer nitrogen-release cycles that fully close the influent valve, and the additional time required for the nitrogen-release cycle should be accounted for in the filter design. Since the DynaSand and Astrasand upflow systems

drawn into the airlift, a separate deg is unnecessary.

Backwashing and Filter Controls During operation of the denitrification filter, solids removed from the wastewater accumulate in the media. Additional solids from the growth of denitrifying bacteria also build up in the filter media. This increases the head loss in the filters. To clean the media, backwashing cycles for the downflow filters are initi ated on the basis of increased head loss through the filter or on a timed basis. All three manufacturers of downflow filters offer air scouring and air-water backwash as part of the backwa Integrated process control systems are offered for the TETRA Denite, elimi-NITE, and Davco filtration systems which control the backwashing, air-scour, and nitrogen-release cycles.
The DynaSand and Astrasand systems operate with a small continu process monitoring tool for the Astrasand filter, the Astrameter system, is used to measure the sand circulation rates at several locations throughout the filter.
Questions remain regarding the bed turnover rate (backwash frequency) and how it relates to maintaining good solids removal while supporting sufficient Available for use with the Astrasand filter, the Astracontrol system was developed to maintain biological activity within the filter under varying conditions.
The control system continuously adjusts the media movement and washing rate to maintain a fixed volume of active biomass in the filter. Studies performed by Siemens Water Systems suggest that optimizing the backwash rate based on hydraulic loads through automation of the airlift provides excellent control of the process (Freed and Pauwels). Parkson Corporation has indicated that chan the DynaSand system5 djust it during

Table 1 Courtesy of Christine deBarbadillo meet a specific requirement. However, the company has not seen a need to a routine operation Methanol Feed Control System Methanol is usually dosed to the filter influent before it is divided among the filter cells. In the Denite system, methanol is dispensed on thebasis of the filter influent flow rate and the concentrations of nitrate in the influent and
effluent, as measured by an online nutrient analyzer. The manufacturer guarantees no net increase in total organic carbon across the filter when this control system is used.
The other manufacturers suggest using the filter influent flow rate and nitrate concentration todetermine the methanol dosage through a flowpaced or feed-forward automatic control system. Although a feed-forward control scheme can reasonably matc

6 h methanol dosing to actual requirements, periods of slight overdosing and sulting increase in concentrations of

e desirable at

f the forward flow for backwashing ed on the same factors as new plants, in addition tothe layout and design ocesses. A case study

st of approximately $1.46 per gallon of rtment of the

EPA acknowledges external peer reviewers J.B.

Siemens. Product literature.
duct_Line /Pages/da vco_denitrification_filter_product_page.aspx
http://www.water.siemens.com/en/Product_ ts/Pages

x

literature

htt n.htm

htt essID=73

RE the re biochemical oxygen demand (BOD) in the filter effluent might be difficult to avoid. In cases in which effluent BOD and nitrate-nitrogen limits are less stringent, the need for a high level of methanol control is related to optimizing chemical usage.

Costs
There are several factors that are related to a denitrification filter system’s capital costs. Depending on the application and overall effluent requirements, itmight b times to use a more conservative design for filters in meeting the required limit. Alternately, pilot testing can be conducted to verify the design loadings. Another f actor that may affect the overall cost of the project includes whether the influent and backwash piping and the valves associated with downflow filters are installed outdoors or housed in a building.
In addition to capital cost, operational costs are also important. The energy costs associated with backwashing, air-scour, and nitrogen-release cycles must be considered, along with a proper accounting of the frequency of these operations. The cost of “retreatment” of spent backwash water must also be included: Filters using only 2 percent o have a lower cost for treatment than those that consume greater amounts of backwash water. Finally, the ability to optimize methanol dosages can affect the operating cost significantly. Some facilities have reduced their chemical consumption as much as 30 percent after implementing more efficient control systems.

Costs will differ for new plants and retrofits. Retrofit costs are more site-specific and vary considerably for any given size category. Retrofit costs are bas

of the existing treatment pr performed for the Maryland Department of the Environment suggests costs in dollars per pound of total nitrogen removed can range from $0.55 to $7.69. For these examples, this equates to a

co wastewater treated (Maryland Depa Environment, 2005).



### A CKNOWLEDGMENTS

Alan Cooper, Christine deBarbadillo, and Neethling for their assistance.



### PRODUCT LITERATURE USED

http://www.water.siemens.com/en/Pro s/Davco_Products/Davco_Products

Lines/Davco_Products/Davco_Produc /davco_astrasand_product_page.asp

Severn Trent Services
http://www.severntrentservices.com/ LiteratureDownloads/Documents/ 650-0001.pdf
F.B. Leopold Company literature
p://www.fbleopold.com/wastewater/ denitrification/denitrificatio
Parkson Corporation
p://www.parkson.com/Content.aspx?ntopicid =139&parent=process&proc

FERENCEStcalf & Eddy. 1979. Wastewater Engineering, Treatment, Disposal, Reuse New York: McGraw-Hill.
tcalf & Eddy. 2003. Wastewater

ngineering, Treatment and Reuse , 4 thed.

7 Me

.

Me E New York: McGraw-Hill.

ust,

bert., D. Parker, J. Wells, and R. Willet. June 2005. Evaluating Denitrification Filters. Water Environment & Technology

. <http://www.environmentalexpert.com/resultEachArticlePDF.aspx?cid= 8563&idmainpage=0&level=2&codi=6694 >

Denitrifying Filters Case Studies: Maryland Department of the Environment, http://www.mde.state.md.us/assets/document/BRF%20Gannett%20FlemingGMB%20presentation.pdf U.S. Environmental Protection Agency, Aug 2002, Nitrification. http://www.epa.gov/safewater/disinfection/tcr/ pdfs/whitepaper_tcr_nitrification.pdf

deBarbadillo, C., R. Rectanus, S. Lam

EPA 832-F-07-014 Office of Water September 2007

# Copyrighted page(s) removed. Copyrighted material is not available in Regulations.gov since it may not be reproduced without consent of the copyright holder.

Removed pages can be viewed at the USEPA Docket Center, Public Reading Room.

Address: 1301 Constitution Ave, NW Room 3334 Washington, DC 20004

Telephone: 202-566-1744

Email: docket-customerservice@epa.gov

# ATTACHMENT V

Process Vent Limit Calculations Based on Mass Flow (see separate Excel file included)

# ATTACHMENT VI

Compiled Revisions to the Rule for Equipment Leaks and Storage VesselsReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 1 of 6 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Attachment VI – Compiled Revisions to the Rule for Equipment Leaks and Storage Vessels

Revisions to 40 C.F.R. § 63.11915
For ease of reference, the Working Group’s recommended changes for Section 63.11915 concerning PRDs and equipment leaks from pressure vessels, as well as previously submitted clarifying changes from the Working Group’s April 5 th letter to the Agency, are included in this Attachment. In the text below, new language is underlined and deletions are in strikethrough:
§ 63.11915 What are my compliance requirements for equipment leaks? For equipment in HAP service (as defined in § 63.12005), you must comply with the requirements in paragraphs (a), (c), and (d) of this section. Paragraph (b) may be used as an alternative means of compliance for certain equipment in HAP service. (a) Requirement for certain equipment in subpart UU of this part. You must comply with §§ 63.1020 through 63.1025, 63.1027, 63.1029 through 63.1032, and 63.1034 through 63.1039 of subpart UU of this part. (b) Alternative requirements for pumps, compressors, and agitators. You must meet the requirements of paragraphs (b)(1) and (2) of this section. For each type of equipment specified in paragraphs (b)(1) and (2) of this section, you must also meet the requirements of paragraph (a) of this section. (1) Rotating pumps. HAP emissions from seals on all rotating pumps, compressors, and agitators in HAP service are to may be minimized by either installing sealless pumps, pumps with double mechanical seals or equivalent equipment, or by complying with the requirements of 40 CFR part 63, subpart UU for rotating pumps. If double mechanical seals are used, emissions from the seals are to be minimized by maintaining the pressure between the two seals so that any leak that occurs is into the pump; by complying with § 63.11925(a) and (b); or equivalent equipment or procedures approved by the Administrator. You must also meet the reporting, recordkeeping, and inspection provisions applicable to each piece of equipment under subpart UU of this part. (2) Reciprocating pumps, rotating compressors, reciprocating compressors and agitators. HAP emissions from seals on all reciprocating pumps, rotating compressors, reciprocating compressors and agitators in HAP service are to be minimized by either installing double mechanical seals or equivalent equipment, or by complying with the requirements of 40 CFR part 63, subpart UU for reciprocating pumps, rotating compressors, reciprocating compressors and/or agitators. If double mechanical seals are used, HAP emissions from the seals are to beReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 2 of 6 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com minimized by maintaining the pressure between the two seals so that any leak that occurs is into the pump; by complying with § 63.11925(a) and (b); or equivalent equipment or procedures approved by the Administrator. (c) Requirements for pressure relief devices. For pressure relief devices in HAP service, as defined in § 63.12005, you must meet the requirements of this paragraph (c) and paragraph (a) of this section, you must comply with the recordkeeping provisions in § 63.11990(c), and you must comply with the reporting provisions in §§ 63.11985(a)(2), (b)(2) and (c)(7). (1) For pressure relief devices in HAP service that discharge directly to the atmosphere without first meeting the process vent emission limits in Table 1 or 2 to this subpart by routing the discharge to a closed vent system and control device designed and operated in accordance with the requirements in §§ 63.11925 through 63.11950, you must install, maintain, and operate release indicators as specified in paragraphs (c)(1)(i) and (ii) of this section or a system or combination of systems as specified in paragraph (c)(1)(iii). Any release to the atmosphere without meeting the process vent emission limits in Table 1 or 2 to this subpart, constitutes a violation of this rule. You must submit the report specified in § 63.11985(c)(7), as described in paragraph (c)(1)(iii)(iv) of this section. (i) A release indicator must be properly installed on each pressure relief device in such a way that it will indicate when an emission release has occurred. (ii) Each indicator must be equipped with an alert system that will notify an operator immediately and automatically when the pressure relief device is open. The alert must be located such that the signal is detected and recognized easily by an operator. (iii) A system or combination of systems must be used to permit operators to readily detect pressure relief device discharges. This may include vinyl chloride ambient area monitoring (as required in § 63.11956), monitoring of process parameters, or similar systems. (iii)(iv) For any instance that the release indicator or the system described in paragraph (c)(1)(iii), as appropriate, indicates that a pressure relief device is open, you must notify operators that a pressure release has occurred, and, within 10 days of the release, you must submit to the Administrator the report specified in § 63.11985(c)(7). This report is required even if you elect to follow the procedures specified in § 63.11895 to establish an affirmative defense. (2) For pressure relief devices in HAP service that discharge directly to a closed vent system and control device designed and operated in accordance with the requirements in §§ 63.11925 through 63.11950 and are required to meet process vent emission limits in Table 1 or 2 to this subpart. Any release to the atmosphere without meeting the process vent emission limits in Table 1 or 2 to this subpart, constitutes a violation of thisReconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 3 of 6 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com rule. You must notify operators that a pressure release has occurred, and, within 10 days of the release, you must submit to the Administrator the report specified in § 63.11985(c)(7). This report is required even if you elect to follow the procedures specified in § 63.11895(b) to establish an affirmative defense. (2) Paragraph (c)(1) does not apply to pressure relief devices in HAP service that discharge directly to a closed vent system and control device or that discharge directly to the recovery system. Any release to the atmosphere without meeting the process vent emission limits in Table 1 or 2 to this subpart constitutes a violation of this rule. (d) Requirements for pressure vessels. Pressure vessel closure devices (e.g., access hatches and manways, sampling ports, gauge wells, caps, hatches, lids, plugs, seals, valves, or other types of fittings that prevent or reduce air pollutant emissions to the atmosphere by blocking an opening in a cover when the device is secured in the closed position) shall be designed and operated with no detectable leaks as indicated by an instrument reading of less than 500 above background. You shall demonstrate no detectable leaks for these components measured initially and annually by the following procedures: (1) Method 21, of part 60, appendix A-7; and (2) The instrument specified in Method 21 shall be calibrated before use according to the procedures specified in Method 21 on each day that leak checks are performed. The following calibration gases shall be used: (i) Zero air (less than 10 parts per million by volume of hydrocarbon in air); and (ii) A mixture of methane and air at a concentration of approximately, but less than, 500 parts per million by volume methane.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 4 of 6 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com Revisions to 40 C.F.R. § 63.11910:
For ease of reference, the Working Group’s recommended changes for Section 63.11910 concerning pressure vessels and the allowance for vapor balancing are included in this Attachment. In the text below, new text language is underlined and deletions are in strikethrough:

(c) For each pressure vessel used to comply with the requirements specified in Table 3 to this subpart, you must meet the requirements in paragraphs (c)(1) through (3)(4) of this section. (1) Whenever the pressure vessel is in hazardous air pollutants (HAP) service, you must operate the pressure vessel as a closed system that does not vent to the atmosphere, e.g., during filling, emptying and purging. The vent stream during filling, emptying and purging must meet the requirements of § 63.11925(a) and (b). Any venting directly to the atmosphere during filling, emptying, or purging constitutes a violation of this rule. You must submit to the Administrator as part of your compliance report the information specified in § 63.11985(b)(10). This report is required even if you elect to follow the procedures specified in § 63.11895 to establish an affirmative defense. (2) Each opening in the pressure vessel must be equipped with a closure device designed to operate such that when the closure device is secured in the closed position there are no visible cracks, holes, gaps or other open spaces in the closure device or between the perimeter of the opening and the closure device.

(3) All potential leak interfaces (e.g., sight glasses; meters; gauges; sampling connections; bolted manways; and hatches) including those for closure devices must be monitored annually for leaks to confirm the conditions of no detectable emissions, as indicated by an instrument reading of less than 500 ppm above background, by the methods specified in §§ 63.11910(c)(3)(i)-(ii)using the procedures specified in § 63.11915 and you may adjust for background concentration. You must comply with the recordkeeping provisions specified in § 63.11990(b)(4) and the reporting provisions specified in § 63.11985(a)(1), (b)(1), and (b)(10). (i) Method 21 shall be used to determine the background level. The instrument shall be calibrated before use each day of its use by the procedures specified in Method 21. The following calibration gases shall be used: (A) Zero air (less than 10 ppm of hydrocarbon in air); and (B) A mixture of methane and air at a concentration of about, but less than, 500 ppm methane.Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 5 of 6 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com (ii) Method 21 shall be used to determine the presence of leaking. All potential leak interfaces shall be traversed as close to the interface as possible. The arithmetic difference between the maximum concentration indicated by the instrument and the background level is compared with 500 ppm for determining compliance.

(4) Pressure vessel closure devices must not discharge to the atmosphere. Any such release (e.g., leak) constitutes a violation of this rule. You must submit to the Administrator as part of your compliance report the information specified in § 63.11985(b)(10). This report is required even if you elect to follow the procedures specified in § 63.11895 to establish an affirmative defense.

(d) Storage vessels may use a vapor balancing system that complies with the requirements specified in paragraphs (d)(1) through (5) of this section and with the recordkeeping requirements specified in § 63.11990. (1) The vapor balancing system must be designed and operated to route organic HAP vapors displaced from loading of the storage vessel to the transport vehicle from which the storage vessel is filled. (2) Transport vehicles must have a current certification in accordance with the United States Department of Transportation (U.S. DOT) pressure test requirements of 49 CFR part 180 for cargo tanks and 49 CFR 173.31 for tank cars. (3) Organic liquids must only be unloaded from cargo tanks or tank cars when vapor collection systems are connected to the storage vessel's vapor collection system. (4) No pressure relief device on the storage vessel, or on the cargo tank or tank car, shall open during loading or as a result of diurnal temperature changes (breathing losses). (5) Pressure relief devices installed on fixed roof, internal floating roof, or external floating roof storage vessels must be set to no less than 2.5 pounds per square inch gauge (psig) at all times to prevent breathing losses. Pressure relief devices may be set at values less than 2.5 psig if the owner or operator provides rationale in the notification of compliance status report explaining why the alternative value is sufficient to prevent breathing losses at all times. The owner or operator shall comply with paragraphs (d)(5)(i) through (iii) of this section for each pressure relief valve installed on fixed roof, internal floating roof, or external floating roof storage vessels. (i) The pressure relief valve shall be monitored quarterly using the method described in § 63.1023(b).Reconsideration: PVC MACT Working Group Follow-up to July 23 Meeting August 16, 2013

Page 6 of 6 The Vinyl Institute, 1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 www.vinylinfo.org www.vinylindesign.com (ii) An instrument reading of 500 parts per million by volume (ppmv) or greater defines a leak. (iii) When a leak is detected, it shall be repaired as soon as practicable, but no later than 5 days after it is detected, and the owner or operator shall comply with the recordkeeping requirements of § 63.11990(c).