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1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 

www.vinylinfo.org www.vinylindesign.com

September 22, 2011

Ms. Jodi Howard

U.S. EPA - Office of Air Quality Planning and Standards 

Sector Policies and Program Divisions 

Coatings and Chemicals Group 

Mail Code: E143-01 

Research Triangle Park, NC 27711

RE: Vinyl Institute Response to EPA Request for Additional Information on Work 

Practices for Gasholders at PVC Resin Manufacturing Facilities – EPA-HQ-OAR2002-0037 

Dear Ms. Howard,

This letter responds to your e-mail of September 15, 2011, requesting any cost and 

emissions data to support The Vinyl Institute’s recommendation that work practices,

such as floating objects on water seals, be used as a means of reducing HAP emissions

from gasholders.

1

 We have consulted with all members of our PVC MACT Working 

Group, and on their behalf submit the following information:

1. Approximately five years ago, Westlake Chemical’s Geismar, LA facility installed

mats on supports over an 18” wide water seal in an effort to reduce fugitive

emissions from a 45 foot diameter gasholder. According to information provided 

by Westlake, the mats alone cost approximately $3,000. Most of the costs for 

this option, however, involve the installation of the mats, which includes the 

installation and use of rigging equipment to lift the mats and other materials into 

place over tank sidewalls, in likely congested areas. The Working Group was 

unable to obtain this information on short notice, but understands that EPA has 

access to cost statistics for such operations.

2. Golden Specialty, Westlake’s testing contractor, conducted tests of the ambient 

air around the Geismar, LA gasholder during the onsite emissions tests for the 

 

1

See Comments of The Vinyl Institute, Inc. PVC MACT Working Group, Document No. EPA-HQ-OAR-2002-0037-0146, at 94-95.
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1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 

www.vinylinfo.org www.vinylindesign.com

PVC MACT Section 114 request in 2009. Using EPA Method TO-16, Long-Path 

Open-Path FTIR Monitoring of Atmospheric Gases, the measurements were nondetect for HAPs, including vinyl chloride. Two possibilities explain this result. 

Either emissions from gasholders have been over-estimated, or the test method 

is not appropriate to measure such low level ambient emissions. 

3. Shintech has recently (since the PVC MACT comment period closed) developed 

an installed cost at their facilities of $5,000 per gasholder for floating objects on 

the water seal.

4. Because measurement of open air evaporation across the gasholder are nearly

impossible, resin producers must estimate release amounts from this type of 

fugitive emission source. Working Group estimates that floating objects would 

achieve a 70% in fugitive emissions from gasholders are based on independent 

laboratory studies that were reported in Verville J, et. al., Estimation of Vinyl 

Chloride Emissions from Gasholders and Validation of In Situ Emission 

Reduction Methods, J Air Waste Manag Assoc. 54(2):172-80, Feb. 2004 and is 

enclosed for your convenience.2

5. The enclosed article reviews several different options for reducing water seal 

emissions. The PVC MACT working Group has examined each type of 

installation and concluded that each has its own drawbacks, as explained in our 

submitted comments. Some floating objects could become dislodged by high 

winds or clog water transfer systems. Stationary windshields could be damaged 

by a bell not travelling completely perpendicular during extension or contraction. 

Oil layers may present engineering and operational challenges to those facilities 

not capable of handling oil contamination in their wastewater systems. 

Upon reviewing the available information and based on its own plant experience, the 

PVC MACT Working Group concluded in its comments that a work practice involving 

floating objects on the water seal would be the most effective means for reducing vinyl 

 

2

Journal of the Air & Waste Management Association by AIR & WASTE MANAGEMENT ASSOCIATION. Reproduced with 

permission of AIR AND WASTE MANAGEMENT ASSOCIATION in the format email via Copyright Clearance Center. Any 

publication of this article beyond this e-mail transmission must have permission.
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1737 King Street, Suite 390, Alexandria, VA 22314 (571) 970-3392 Fax (571) 970-3271 

www.vinylinfo.org www.vinylindesign.com

chloride emissions from the gasholder water seal by an estimated 70% and would be 

MACT. The Vinyl Institute hopes this information meets your needs on this important 

issue. Please do not hesitate to contact me if you have any questions on this 

information, or require additional information. 

Sincerely, 

Richard P. Krock

Technical Director

e-mail: rkrock@vinylinfo.org

phone: 571-970-3392

cell: 571-216-4474