Attachment VI to PVC MACT Working Group Letter to EPA

Examples of Major Issues of Concern with the Final PVC MACT Emission Limit Compliance Date of April 17, 2015

# Description Summary Compliance Deadline Burden

1. Wastewater Stripper 

Effluent Limitation

No new PVC Unit can meet the effluent 

Total non VCM organic HAP (TOHAP) 

limit of 0.018 ppm

Existing PVC area sources cannot meet 

the effluent Total non VCM organic HAP 

(TOHAP) limit of 0.018 ppm and would 

have to cease operation.

Existing PVC Units that use any vinyl 

acetate monomer, methanol, ethylene

glycol, formaldehyde, aldehydes or other 

soluble/ partially soluble HAPs cannot 

meet the final TOHAP limit of 110 ppm.

Uncertain WW limits; therefore, if current 

limits remain, affected facilities may have to:

 Discontinue products that result in 

WW TOHAP above limit;

 If technically possible, reformulate

resin recipes and attempt to have 

customer requalify the new product, 

, which could also entail redesign,

capital investment, and 

construction/startup along with 

recertification of the product, all of 

which takes time; 

 Discontinue producing VCM/VAM 

copolymer resins;

 Discontinue operations at area 

sources;

 Develop new WW treatment

strategies and implement if 

achievable.

2.a. Process Vents and 

Closed Vent Systems: 

Any vent that could 

divert regulated gases 

from the control device 

(bypass) requires:

a. A flow 

indicator/alarm 

system; or,

b. A car-seal 

mechanism. 

As the rule currently stands:

ANY HAP release, no matter how small, 

from a by-pass valve (e.g., low leg 

drain) would be considered a violation. 

If this emission control requirement remains 

as finalized, then PVC Units will have to 

assess the liability of having hundreds of 

valves that could potentially vent to the 

atmosphere under any circumstance. The 

assessment may require the following steps 

to limit liability:

 Hard-piping low-leg drains and highpoint bleeds through a closed vent 

system that vents to a control 

device. 

 Routine maintenance activities, even

after equipment opening procedures 

have been satisfied, will result in 

violations. It is technically impossible 

to open any piece of equipment that 

operates at other than atmospheric 

pressure without opening a vent 

valve in the system to equalize 

pressure. 


Attachment VI to PVC MACT Working Group Letter to EPA

Examples of Major Issues of Concern with the Final PVC MACT Emission Limit Compliance Date of April 17, 2015

# Description Summary Compliance Deadline Burden

2.b. Process Vent 

Violation: Broken carseal

The rule currently reads:

“A broken seal or closure mechanism 

or a diverted valve constitutes a 

violation from the emission limits in 

Table 1 or 2 to this subpart.”

As a benchmark, a typical polyolefins Unit 

can break between 200-300 car-seals a year 

in order to perform maintenance. A PVC 

Unit’s rate would likely be higher. 

At a penalty of $37,500/violation, the 

potential penalties for this requirement are 

substantial. 

Hence, If this emission control requirement 

remains as finalized, then PVC Units will have 

to assess the liability and compliance burden 

of car-sealing any valve that could potentially 

vent to the atmosphere. The assessment 

may require the same action at Item 2.a. in 

order to limit liability.

3. Pressure Relief 

Devices (PRD):

All PRDs that vent to 

atm are now required 

to be equipped with an 

electronic alarm 

system to indicate 

when PRD is open

As per the final rule preamble: “...you are 

required to install a release indicator 

on each PRD that would be able to 

identify and record the time and 

duration of each pressure release...” 

[77 Fed Reg 22860]. 

Once equipment is proven and becomes 

available, this will cost multiple millions of 

dollars per plant to implement. Since the 

equipment to meet the requirement may not 

be commercially available in the quantities 

needed and/or safe to operate in a chem. 

Plant, industry is uncertain how to meet this 

requirement. If the requirement continues to 

stand, then Industry may have to vent each 

PRD through a closed vent system/control 

device (venting to a control device does not 

require an electronic alarm system). 

 If increasing the flow rate and HAP 

concentration to the control device, 

the system will have to be evaluated 

to determine if an increased flow 

and/or concentration can be handled 

within the existing emission control 

system. If it cannot be handled, then 

a redesigned or new system will be 

necessary.

Note: Certain PRD releases may be unsafe 

to vent to a control device.

4. Storage Vessels Vapor Balancing for rail car loading should 

be allowed, as per other MACT & 

proposed Uniform Standards

If vapor balancing is not allowed, PVC Units 

will have to vent through a closed vent 

system to a control device.

 If increasing the flow rate and HAP 

concentration to the control device, 

the system will have to be evaluated 

to determine if an increased flow 

and/or concentration can be handled 

within the existing emission control 

system. If it cannot be handled, then 

a redesigned or new system will be 

necessary.
Attachment VI to PVC MACT Working Group Letter to EPA

Examples of Major Issues of Concern with the Final PVC MACT Emission Limit Compliance Date of April 17, 2015

# Description Summary Compliance Deadline Burden

5. Stripped Resin Limits 

for Existing Sources

Challenges to subcategorization and UPL 

calculation methods have created 

uncertainty whether the limits in the final 

rule will be re-determined

Significant capital and lead time is needed to 

either reconfigure or replace a resin stripper.

6. Process Vent: Overlap Emission Limit Overlaps for Combined 

Sources: EPA is establishing a precedent 

for overlapping emission limits for control 

devices. If a PVC MACT regulated vent 

stream enters a control device regulated 

by another MACT, the combined source 

must demonstrate compliance with the 

PVC MACT emission limits. (Ex. 1% PVC 

vent gas combined with 99% HON 

regulated vent gas must comply with PVC 

MACT).

This issue also includes a new compliance

demonstration strategy for HON affected

control devices (CPMS/CEMS must meet

PVC MACT’s requirements; along with 

HON’s).

EPA finalized a new subcategory scheme that 

was not in the proposed rule:

 PVC-only process vents; and 

 PVC-combined process vents. 

A VCM Unit, which currently controls

emissions from the related PVC Unit under 

HON, is now affected by the more stringent 

requirements of the PVC MACT, unless the 

PVC Units vent to its own control device.

If the rule stands as currently finalized, then 

PVC-Combined Units may be driven to 

segregate out the PVC emissions from the 

VCM emissions by installing a new Thermal 

oxidizer/Scrubber system (PVC-Only). This 

type of effort requires:

1. State and Federal air permitting 

action for GHG and traditional 

pollutants (Permit application 

development and pre-construction 

approval takes 12-24 months)

2. Design; capital expenditure 

approvals, equipment procurement, 

and construction/Startup time; along 

with,

3. VCM/PVC production demand 

considerations for shutdown/tie-ins