SAN JOAQUIN VALLEY UNIFIED AIR POLLUTION CONTROL DISTRICT 

FINAL STAFF REPORT 

Revised Proposed Amendments to 

Rule 4682 (Polystyrene Foam, Polyethylene & Polypropylene Manufacturing) 

 

Prepared by: George Heinen, Supervising Air Quality Engineer 

 Manuel Salinas, Air Quality Engineer 

Reviewed by: Joven R. Nazareno, Senior Air Quality Engineer 

 Ellyce Baldwin, Supervising Air Quality Inspector 

 Mark Schonhoff, Senior Air Quality Engineer 

September 20, 2007 

I. REASONS FOR RULE DEVELOPMENT AND IMPLEMENTATION 

A. District Attainment Status of National Ambient Air Quality Standards 

In the San Joaquin Valley Air Basin (SJVAB), monitored levels of ozone exceed 

National Ambient Air Quality Standards (NAAQS), which are set at levels that protect 

public health and welfare. Consequently, the U.S. Environmental Protection Agency 

(EPA) has classified the SJVAB’s air quality as serious for its nonattainment designation 

for the federal eight-hour ozone NAAQS. Under the now revoked federal one-hour 

ozone standard, the SJVAB was classified as extreme nonattainment. 

The federal Clean Air Act (CAA) requires air districts in nonattainment areas to prepare 

plans that are designed to achieve and maintain the NAAQS by the earliest practicable 

date, and no later than attainment deadlines given in the CAA. The San Joaquin Valley 

Unified Air Pollution Control District (District) adopted the Extreme Ozone Attainment 

Demonstration Plan (EOADP) on October 8, 2004. The EOADP calls for a reduction in 

volatile organic compound (VOC) emissions by 2010 by amending Rule 4682 

(Polystyrene Foam, Polyethylene & Polypropylene Manufacturing) to further reduce 

VOC emissions by introducing more stringent limits. 

Although EPA has revoked the federal 1-hr ozone NAAQS the VOC emission reduction 

commitment from Rule 4682 Amendment must still be met. EPA’s final Phase 1 rule 

implementing the 8-hr ozone NAAQS (69 FR 23858 and 70 FR 30592) identifies a 

number of federal CAA requirements that applied to an area by virtue of its 1-hr ozone 

nonattainment classification and that continue to apply after revocation of the 1-hr 

ozone NAAQS [40 CFR 51.900(f)]. Because the SJVAB was classified as extreme 

nonattainment, and because an attainment demonstration (as defined by 40 CFR 

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51.905) is one of the requirements, the EOADP becomes one of the requirements that 

still apply to the SJVAB by virtue of its former classification under the now-revoked 1-hr 

ozone NAAQS. The EOADP uses the VOC emissions reductions from the Rule 4682 

Amendment to project attainment. Without the reductions from the Rule 4682 

Amendment, the EOADP does not project attainment and therefore does not meet the 

requirements of 40 CFR 51.905. Thus the District must proceed with Rule 4682 

emission reductions even though the standard was revoked. 

This rulemaking project is part of the District’s ozone attainment strategies. As such, 

this project is subject to the following state and federal requirements: 

• Ozone attainment plans need to implement control measures as expeditiously as 

practicable, and provide for attainment. Clean Air Act (CAA) Section 172(c)(1) 

• Ozone attainment plans should provide for best available retrofit control technology 

(BARCT) for existing permitted sources. California Health & Safety Code (H&SC) 

Section 40919(a)(3) 

• Ozone attainment plans should include “all feasible control measures.” H&SC 

Section 40914(a)(2) 

The California Air Resource Board (ARB) interprets “every feasible control measure to 

mean that, at a minimum, a district consider regulations that have been successfully 

implemented elsewhere. They should also consider going beyond what has already 

been accomplished by evaluation of new technologies and innovative approaches that 

may offer potential emission reductions. Further, districts should consider not only 

technological factors, but also social, environmental, economic (e.g., cost 

effectiveness), and energy factors which prevail in the District, along with the resources 

realistically available to the district to adopt, implement, and enforce the measures.” 

To satisfy the attainment goals of the ozone plan, District staff would amend Rule 4682 

to implement the emission control measure in the District’s ozone attainment plan. The 

draft amendments to Rule 4682 will seek to obtain as much reduction of VOC emissions 

from existing polystyrene foam, polyethylene, and polypropylene product manufacturing 

operations as expeditiously as practicable, technologically feasible, and economically 

reasonable, as determined by the District’s Governing Board. The draft amendments to 

Rule 4682 achieve emissions reduction by requiring either compliance with a VOC 

emission limit or the operation of a VOC capture and control system to reduce the 

emissions from the manufacturing and storage of polystyrene, polyethylene, and 

polypropylene products. This rulemaking project is also intended to satisfy the state 

and federal requirements identified above. 
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B. Description of the Project 

This category was listed in the Ozone Rate of Progress Plan as an all feasible measure 

suggested by the EPA. Amending Rule 4682 is intended to reduce VOC emissions 

from manufacturing polymeric foam and foam products by specifying VOC emission 

limits or emission control devices. The two major categories of processes in this 

category are extruded foam products and molded foam products. Although there are 

key differences between the two processes, each process employs a blowing agent to 

create spaces in the plastic structure to produce a strong, but lightweight material with 

good thermal insolating properties that is inert to water and grease. 

The most common blowing agent used is in the Valley is pentane, but 

chlorofluorocarbons (CFC) and carbon dioxide, (CO2) have also been used in other 

locations. Pentane is a VOC that is a precursor to ozone and therefore a pollutant of 

interest to the District. CFC are ozone-depleting chemicals, which can rise to the upper 

atmosphere and impact the stratospheric-ozone layer, so they are not typically found in 

modern facilities. Non-VOC blowing agents, such as carbon dioxide, CO2, may be 

used in some cases, but CO2 systems require specifically constructed equipment and 

are not suitable making for all products, due to the affect on the foam characteristics 

compared to pentane. One Valley facility uses 10% CO2 in conjunction with a VOC 

blowing agent. 

Extruded Foam Product Manufacturing Overview 

 

Extruded foam products begin with plastic beads that typically contain little or no VOC 

content. The beads are delivered in bulk and pneumatically transferred to storage silos 

until needed. Basic steps in the manufacturing process include: the mixing and 

extrusion of the foam sheet; storing or aging of the sheets, thermoforming the sheets 

into the desired shapes using heat and vacuum; and packaging and storage of the 

finished products. Excess material that is trimmed off during manufacturing is 

recovered and recycled either on-site or off-site at the bead manufacturing facility. 

The extrusion process consists of moving the beads from the storage silos and heating 

the beads with a VOC-containing blowing agent, under pressure in an auger. As the 

materials mix, the blowing agent expands and forms bubbles in the plastic which is then 

extruded through a forming die to form a continuous foam sheet of a desired thickness. 

The sheet of foam is cooled, cut to the needed width, and moved to a storage area for 

aging. At this point, the concentration of the entrained blowing agent in the foam is too 

high for manufacturing purposes and a period of off-gassing or aging is required. 

After aging, which can take several days, the foam sheets are moved to the 

thermoforming machines. These machines use a combination of heat and pressure to 

which produce a variety of products including food-grade trays and packaging for sales 

and service. The completed products are then packaged and sent to storage areas to 
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continue the off-gassing of blowing agents and to await shipping. After manufacturing, 

the completed product can still retain 50% or more of the original blowing agent 

introduced during the extrusion process. 

The recovery and recycling of excess or trimmed material includes shredding or 

grinding the material until it is small enough to be reintroduced to the extruder. The 

recycled material still contains some percent of blowing agent from the original foam 

manufacturing process, but more blowing agent can be added during extrusion, to make 

up for the amount lost during manufacturing. 

The primary points of VOC emissions are the extrusion and sheet forming process; 

aging of the rolls; thermoforming; and finished goods storage, but the products continue 

to release VOC from the residual blowing agent contained in the air pockets. As will be 

discussed later, the existing operations may have VOC capture and control equipment 

to reduce some or all of the manufacturing emissions. 

Most extruders produce long sheets of foam for thermal molding or other purposes, but 

some extruders can also produce smaller products such as loose fill material which is 

used as packing material to cushion items during shipping. There are currently no loose 

fill manufacturers in the Valley. 

Molded Foam Product Manufacturing Overview

Molded foam products use pre-expanded beads and direct-injected molds, rather than 

extruded foam sheets and thermoforming machines. The raw material for molded foam 

typically contains the needed blowing agent when it is received at the facility. The 

material handling and storage containers must therefore have VOC emission controls to 

reduce emissions from the raw materials. 

Prior to molding, the beads are pre-expanded using heat to slightly expand the blowing 

agent and puff the beads. The beads are then cooled and stored in emission-controlled 

containers for intermediate aging and stabilization. Molding involves filling the mold 

with puffed beads; heating the beads to complete their expansion; and releasing the 

molded product. Depending on the product, a negative pressure or vacuum may be 

used to better fill the mold and produce a uniform contact with the mold surface. 

Finished products may require trimming to reduce flashing or seam material that 

escapes at mold joints or pour points. Any waste materials are collected for recycling. 

Finished materials, which can retain significant portions of the blowing agents, are 

packaged and moved to storage until shipping. 

The primary points of VOC emissions are the raw material and storage systems, preexpansion and puff bead storage, molding; and finished goods storage, but the products 

continue to release VOC from the residual blowing agent contained in the air pockets. 
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As will be discussed later, the existing operations may have VOC capture and control 

equipment to reduce some or all of the manufacturing emissions. 

There are three major types of molding: blocks, cups, and shapes. Block molders 

produce large blocks of foam which are cut into sheets such as building insulation, or 

other desired shapes after molding. Cup molders make cups, bowls and other similar 

containers. Shape molders make custom foam shapes such as grape shipping boxes 

or to packing inserts to protect electronic equipment during shipment. 

Valley Foam Product Operations 

District staff identified twelve manufacturers of various located within the District. The 

majority of manufacturers in the District are manufacturing polystyrene foam products. 

Three manufacturers produce products from extruded polystyrene (XPS) while the 

majority of the operators use expanded polystyrene (EPS) to mold foam products. 

Molders include one foam cup manufacturer, several grape box manufacturers and a 

few specialty products manufacturers. Currently, there are no block molding 

manufacturers operating in the District so rule amendments will not address this 

industry. Any new facility would undergo the New Source Review, which include a Best 

Available Control Technology (BACT) determination process, so Rule 4682 will not 

attempt to set BACT for new operations. 

C. Rule Development Process 

As part of the rule development process, District staff conducted a public scoping meeting 

in July 2006, the first workshop in April 2007, a technical working group meeting in June 

2007, and a final workshop in July 2007. At the scoping meeting and workshop District 

staff solicited comments from interested parties, affected industry operators, and 

stakeholders. Affected source operators, consultants, vendors and manufacturers of 

control technologies, and trade associations were also requested to provide technical 

feasibility and compliance cost information which would be useful in developing the 

amended rule. The information obtained from the public meetings may be used to develop 

the proposed amendments to the rule and staff report. 

Pursuant to state law, District staff are required to perform a socioeconomic impact 

analysis prior to the adoption, amendment, or repeal of a rule that has significant air quality 

benefits or that will strengthen emission limitations. As part of the District socioeconomic 

analysis process, District staff sought a limited number of representatives from interested 

groups to participate as members of a Focus Group. The Focus Group was to assist 

District staff in determining the appropriate method of gathering information on regulatory 

compliance costs and business impacts resulting from compliance with the rule. The 

results of the socioeconomic analysis were published in a report along with the refined 

version of the proposed rule to the public and interested parties. 
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D. Summary of Revised Proposed Amendments to Rule 4682 

Following are the major changes proposed for Rule 4682. In establishing proposed 

VOC emission limits, District staff considered the limits that have been achieved in 

practice, as well as limits achievable by feasible control technologies. District staff 

evaluated BACT determinations established by the District, other California air districts, 

other states, including those that are recommended by control technology 

manufacturers and stakeholders. These changes are based on similar rules from other 

California air districts and BACT determinations with the District. 

Affected operators would have to comply with one of four emission control options: 

1. Demonstrate that they emit no more than 2.4 lb of VOC for each 100 pounds 

of total material processed, or 

2. Use a non-VOC blowing agent, or 

3. Control all manufacturing emissions with an approved emission control 

system and store the finished product in a controlled warehouse for 24 or 48 

hours, or 

4. Demonstrate that they release no more emissions than would have occurred 

if complying with option 3. 

Operators had commented that the demonstration option (number 4 above) needed 

clarification. Rule language was added to outline an option that would be considered 

equivalent to the demonstration. Definitions and rule language was added or modified 

to clarify and strengthen rule compliance. Recordkeeping, testing and compliance 

dates for the new requirements were updated or added. 

II. CURRENT AND PROPOSED REGULATIONS 

Rule 4682 currently limits emissions from polystyrene foam, polyethylene, and 

polypropylene manufacturing, but only for selected operations and equipment within the 

process. Those selected operations are currently defined as controllable VOC emission 

sources. This rule would be expanded to include VOC emission reduction or control 

from all manufacturing processes including product curing areas and general product 

storage areas, similar to those employed by several of the existing sources. 

A. Existing Rule 4682 

Rule 4682 was adopted on May 21, 1992, and subsequently amended on December 

17, 1992, and June 16, 1994. The purpose of Rule 4682 is to limit VOC and 

chlorofluorocarbon (CFC) emissions from manufacturing and processing of polystyrene 

foam, polyethylene, and polypropylene and from the storage of VOC blowing agents. 
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The rule applies to any polystyrene foam, polyethylene, and polypropylene 

manufacturing and processing operations. 

Certain provisions of the current rule do not apply to manufacturing and processing 

operations using polymeric materials containing less than 1 percent volatile organic 

compounds by weight, and not using a blowing agent in their process. 

The rule requirements contain options for compliance. The options include using non 

VOC or CFC blowing agents, operating with a collection system and control which 

abates the captured emissions, or controlling VOC emissions with an alternative method 

that achieves emission reductions equivalent to the collection system and thermal 

oxidizer. The rule also requires emission control systems for VOC blowing agent 

storage and contains provisions for recordkeeping. 

B. Requirements in Other California Air Districts 

District staff considered the standards/requirements in the rules of other California air 

districts for similar manufacturing operations. In particular, District staff evaluated the 

Bay Area Air Quality Management District (BAAQMD) Rule 52 (Polystyrene, 

Polypropylene, and Polyethylene Foam Product Manufacturing Operations) and the 

South Coast Air Quality Management District (SCAQMD) Rule 1175 (Control of 

Emissions from the Manufacture of Polymeric Cellular Foam Products). 

BAAQMD Rule 52: 

BAAQMD Rule 52 requires control of emissions from foam product manufacturing 

operations by complying with specific VOC emissions limits depending on the product 

type or by installing and operating an approved VOC emission control system. 

• “Manufacturing operations” are defined as: a production line or lines consisting 

of all steps in the processing of a polymer or resin, from the receipt of raw 

polymeric material by the manufacturing facility through the final step prior to 

shipment of the finished foam product that results in a change in the form, 

chemical composition, or any chemical or physical property of the material, and 

that results in VOC emissions to the atmosphere. Individual steps include, but 

are not limited to, expandable bead storage, finished product storage/aging, 

extrusion, expansion, softening or annealing, intermediate (pre-puff) 

storage/aging, decomposition, molding, grinding, and forming. This definition 

covers a broader range of processes than the definition on District 4682. 

• Polyethylene and polypropylene foam product manufacturing operations must 

have collection systems (85% efficiency) and a control system (98%). 
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• Polystyrene Foam manufacturers must meet emission limits, depending on the 

product line. These limits are 

o 2.4 lb VOC/100 lb of raw material for block molders and loose fill; 

o 2.7 lb VOC/100 lb of raw material for shape molders; and 

o 2.89 lb VOC/100 lb of raw material for cup molders. 

SCAQMD Rule 1175: 

SCAQMD Rule 1175 basically prohibits a VOC blowing agent for any operation except 

expandable polystyrene (EPS) molding operations. 

• For EPS molding operations, Rule 1175 requires that manufacturing emissions 

and residual blowing agent total to less than 2.4 pounds per 100 pounds of raw 

material processed. 

• Operators who could not achieve the above standards are required to install 

and operate an approved VOC emission control system. SCAQMD also final 

manufactured products to be stored in a controlled warehouse for 48 hours for 

EPS operations processing more than 400 tons per year and 24 hours for all 

other operations. 

• Rule 1175 defines manufacturing operations as: every step of the processing of 

a polymeric material from delivery of the raw material, include the first 48 hours 

of storage of the final product. 

SCAQMD Rule 1175 is currently open for amendment. Based on the draft language, 

the amended rule would allow block molding manufacturers to employ a cost-effective 

compliance alternative that still produces equivalent emission reductions. According to 

the June 2007 Preliminary Draft Staff Report, SCAQMD staff will propose allowing a 

block manufacturer to over-control manufacturing emissions and use beads with less 

blowing agent instead of controlling warehouse emissions. The proposed overall 

control efficiency of the manufacturing emissions is 93 percent. Preliminary analysis 

indicates that South Coast’s proposal is equivalent to the District’s proposed 

Compliance Option 3 as it applied to block manufacturers. Although the District has no 

block manufacturers, this option can apply to other types of foam manufacturing. The 

proposed rule language includes adequate language to require additional controls, if 

necessary, to demonstrate equivalence. The VOC emission standard of 2.4 lb per 100 

lb of raw material has not been proposed to be amended and is considered achieved in 

practice. The SCAQMD proposed rule and SCAQMD June 2007 preliminary draft staff 

report are included in this report as Appendix F. 

 

C. Affected Sources and Control Technology 

Rule 4682 was implemented to reduce emissions of VOC from this source category. 

Manufacturers within the District are still utilizing VOC, primarily pentane and butane, as 

a blowing agent. Possible controls include switching to an alternative, non-VOC 
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blowing agent, employing capture and control systems for the VOC emissions, 

modifying the manufacturing process, and using materials with lower VOC contents. 

Currently in the District there are sources that have changed to lower VOC-containing 

blowing agents and utilize regenerative thermal oxidizers or boilers for control of VOC 

emissions. The requirements in the rule provide options for compliance for those 

sources that cannot change blowing agents. There are operators in the District 

achieving control of manufacturing emissions including warehouse areas and/or 

meeting the VOC emissions standards added into the current draft of the rule. There is 

also a facility, subject to the rule, that chose to collect and control the emissions by 

operating with a permanent total enclosure on their manufacturing operation.

General information on available control technologies follows: 

Adsorption Vapor Recovery: 

Adsorption vapor recovery is accomplished by passing the VOC-laden gas through 

beds containing adsorbents that have a high surface area to weight ratio. Typical 

adsorbents are activated carbon, zeolite, or organic polymers. As the gas stream 

passes through the bed, organic compounds adsorb weakly onto the adsorbent’s 

surface. Adsorption of the hydrocarbon molecules proceeds until the available surface 

area is filled or saturated with VOC molecules. The VOC molecules are retained until 

the regeneration step, or disposal of the spent adsorbent. 

Desorbing or removing captured VOCs regenerates the adsorbent. There are three 

basic types of adsorption systems available to recover or remove hydrocarbon vapors 

from an air stream. Two of these systems regenerate the adsorbent in-situ for reuse. 

The third system requires removal of the adsorbent to another site for regeneration. 

The two systems that provide in-situ regeneration are: Pressure Swing Regenerated 

Systems and Thermally Regenerated Systems. In the first system, decreasing the 

pressure or providing a backpressure creates a relative vacuum that pulls the capture 

VOC off the adsorbent. The second method involves increasing the temperature of the 

bed to evaporate off the captured VOC. In both systems, the released VOC would be 

vented it to a destruction system or chiller/condenser, depending on the value of the 

recovered VOC. These regenerative adsorption systems have the advantage of 

concentrating the collected VOC for either reuse or efficient oxidation, compared to a 

thermal oxidize. 

A third type of system, which requires removal of the absorbent to another site for 

regeneration or disposal, is a once through single use or canister system. Canister 

systems can usually be purchased directly from the manufacturer, but given the high 
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volume of the exhaust stream and the amount of emissions to be controlled, nonregenerative systems would be less practical than on-site regeneration system. 

Thermal Oxidation (Incineration): 

A thermal oxidizer (TO) destroys VOCs by the process of combustion. A basic TO 

system consists of a combustion chamber, burner, stack, and combustion controls. All 

hydrocarbons are oxidized to carbon dioxide and water vapor by the proper mix of 

temperature, residence time and turbulence within the reactor chamber. Combustion of 

the contaminated gas stream occurs at high temperatures, normally 650o

C to 870oC 

(1,200oF to 1,600oF) when treating low concentration streams. The relatively lowpressure, low-temperature of the TO does not favor NOx production so the amount of 

NOx produced by the combustion is typically much less than the VOC destroyed. 

 

TO systems can be divided into recuperative or regenerative systems; based on 

methods used to increase operating efficiencies by capturing heat from the combustion 

process. Recuperative TO systems increase fuel efficiency by use of a gas pre-heating 

section and a heat recovery section to capture waste heat to preheat incoming air. Heat 

recovery can be as high as 70%, significantly reducing the amount off fuel needed to 

maintain the TO at its operating temperature. 

Regenerative TO systems use a ceramic heat-exchange bed to preheat process air to 

within 5% of the oxidation temperature. A regenerative TO system provides extremely 

high thermal-energy recovery; up to 95% of heat energy can be recovered. PM10 and 

VOC conversion efficiencies range from 97% to 99.9% for recuperative and 95% to 99% 

for regenerative TO systems. 

Boilers: 

Boilers can be an appropriate VOC control technology at EPS foam product 

manufacturing facilities because they provide necessary process steam for the 

operation and control VOC emissions. Boilers can be modified or designed to burn the 

collected vapors via direct combustion and decrease the boiler’s fuel consumption. 

Boilers at these types of facilities have demonstrated VOC destruction efficiencies of at 

least 98% by weight. 

Lower-VOC Beads and CO2: 

For some molding operations, it may be possible to reduce VOC emissions by starting 

with beads that contain 2.4 to 4.0 percent blowing agent rather than beads with 4.0 to 

6.5 percent blowing agent. The lower the initial amount of blowing agent, the fewer 

emissions will be released during manufacturing and the lower the residual quantity. As 

noted earlier, the SCAQMD is proposing to amend their rule to allow the use of 60% 
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low-pentane beads (less than 4% blowing agent) and 40% mid-pentane beads (less 

than 5.2 %blowing agent) as a control option for block manufacturers, in conjunction 

with over controlling other operations. Such beads, however, may not be suitable for all 

processes and products since the blowing agent determines the characteristic of the 

final product. 

As stated earlier, CO2 is sometimes used as a blowing agent, typically mixed with a 

traditional blowing agent, but it does not always produce acceptable results. The 

exfiltration rate of the blowing agent affects the size of the small voids in the foam, 

which impact product qualities. The exfiltration rate also determines material strength 

during cooling process because if there is insufficient blowing agent, the holes will sag, 

changing the physical properties of the foam. 

Manufacturing Process Modifications: 

For some operators, modifications to their manufacturing process can be made that will 

enhance their VOC capture and control system. Many foam molders, for instance, use 

VOC controls on their mold vacuum lines. This efficiently controls VOC during molding 

while minimizing the amount of air that would otherwise have to be controlled from a 

traditional collection hood over the molding machinery. 

According to the SCAQMD staff, a cup molder was able to modify their pre-expansion 

process to drive off more unneeded blowing agent into an existing control device and 

meet the 2.4 lb VOC limit. It is not possible to completely eliminate the blowing agent 

which is need in the molding stage, but the process modification eliminated, in a 

controlled manner, VOC emissions which would otherwise have been released during 

molding or as post-processing residual. Not every manufacturer will, however, be able 

to make identical reductions due to operational, physical layout, and product quality 

considerations. 

D. Revised Proposed Amendments 

In developing the draft amendments to Rule 4682, District staff evaluated the 

requirements of BAAQMD Rule 52 and SCAQMD Rule 1175 which staff believe as 

meeting the standards for BARCT and all Feasible Control Measures. Based on staff’s 

evaluation, the following are the draft major amendments to Rule 4682: 

1. Sections, 1.0 Purpose and 2.0 Applicability – Modified the language of these 

sections to make them clearer. 

2. Section 3.0 Definitions – Added nine new definitions for terms used in the 

proposed amendments: APCO, ARB, Approved Emission Control System, 

Certificate of Analysis, EPA, Low-pentane Bead, Manufacturing Emissions, 

Manufacturing Operation, Mid-pentane Bead and Raw Material. These 
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definitions were developed to reflect the most stringent rule in place. In 

particular, the definition for manufacturing emissions now includes all processes, 

compared to the current rule which only included a short list of process points. 

3. Section 4.1 (Exemption) – The existing language pertaining exempts facilities not 

using a blowing agent, either in the raw material or added during the 

manufacturing process. It was suggested that the language be changed to 

exempt operators not using a blowing agent which contains VOC or CFC, but 

that change would be a relaxation of the current rule. Section 5.3.2, however 

does recognize the exclusive use of such blowing agents to be an acceptable 

compliance option. 

4. Section 5.0 Requirements – Section 5.3, which is effective 36 months after rule 

adoption, provides four methods with which an operator can comply with the rule. 

These options are based on the current SCAQMD rule. The options include 

 1. Demonstrate that they emit no more than 2.4 lb of VOC for each 100 pounds 

of total material processed, or 

2. Use a non-VOC blowing agent, or 

3. Control all manufacturing emissions with an approved system and store the 

finished product in a controlled warehouse for 24 or 48 hours, or 

4. Demonstrate that they release no more emissions than would have occurred 

if complying with option 3. Based on stakeholder comments, operators using 

VOC-limited beads and controlling 93% of the processing emissions are 

assumed to be in compliance with option 4, unless the APCO determines 

additional controls are required. 

Compliance Option 1: 2.4 lb VOC per 100 pounds raw material limit 

The proposed 2.4 lb VOC limit includes all uncontrolled emissions released 

during manufacturing and the residual amount of blowing agent contained in the 

finished product. This standard is equivalent to the SCAQMD and is already 

being achieved by a SCAQMD cup molder and, on at least two new lines, of a 

Valley foam extruder. Staff's initial review of the existing operating permits and 

residual VOC content information provided by the operators indicates that the 

limit may be already achieved by some Valley shape molding operations. 

The difficulty with complying with this option is the natural variability in the 

material received for molding operations. Extruders can closely control their 

VOC content during the extrusion process by metering in the desired amount for 

the raw material. Molders have to rely on the supplier, transportation conditions 

and time, as well as the prevailing temperature and humidity conditions in the 

manufacturing plant. Since there is no continuous, real-time method of verifying 

the VOC content of both the raw material and the finished product, staff propose 
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to use a 30-day average to calculate compliance. That will help smooth out the 

naturally occurring variations on material VOC content. In keeping with EPA 

policy, the rule also states that any violation of the 2.4 lb VOC standard 

represents a separate violation on each of the 30 days during that period. 

The SCAQMD does not require a calculation based on a 30-day average, just 

that it be demonstrated that the limit is met. Therefore, the District rule is more 

stringent, even allowing for the equivalent limits. Further, the District requires the 

operator make a calculation every 30-days which demonstrates continued 

compliance with the standard based on operational data. Each demonstration 

must be pre-approved by the APCO and EPA. Permit conditions will be required 

to ensure enforceability of the demonstration. 

The BAAQMD requires the limit be met "at all time", but it is not clear how that 

would be demonstrated on a continuous base. Also, some of their limits are 

higher that those proposed by the District so on the whole, the District's rule is 

considered to be at least as stringent. All three rules require monitoring and 

recordkeeping of control equipment operating parameters to ensure continued 

compliance with the assumption on which the VOC limit determination would be 

based. 

During the workshops, operators had originally requested a VOC emission 

standard, based on raw material throughput, for each process, similar to those of 

the BAAQMD rule. To be assured of rule stringency, we are required to adopt 

the single South Coast standard, which is the more stringent of the rules. Based 

on existing operations, the 2.4 lb VOC limit appears to have been achieved in 

practice. 

Compliance Option 2: Use of a non-VOC blowing agent 

The use of a non-VOC, non-CFC blowing agent is in the existing rule and 

recognizes that alternative blowing agents have been developed that can prevent 

VOC emissions without harming the stratospheric-ozone layer. As previously 

mentioned, such alternatives are not necessarily feasible for all products. Also, 

modifications to an existing facility to handle the alternative blowing agent could 

amount to a complete rebuild of the material handling systems, controls and 

safety systems. This option, is provided for those manufacturers, who may be 

able to avail themselves of such materials. 

Compliance Option 3: Control of the manufacturing emissions and warehouses 

This option is included to fulfill the state requirement for All Feasible Control 

Measures. Like Compliance Option 1, it has been part of the SCAQMD rule for 

over a decade and is achieved by a Valley foam extruder. Stakeholders cite 

concerns with the mandatory 24/48 hour warehouse provision because it of the 
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cost of controls and construction, space requirements, delays in shipping, and 

safety concerns. These concerns are raised despite two Valley operators, which 

currently operate controlled warehouses. Based on the stakeholder comments, 

however, it is unlikely that other operators will choose this compliance option. 

Rule language has been added to show how the emissions equivalent to this 

option would be calculated. This information would be necessary for operators 

who choose to comply with Compliance Option 4. 

Compliance Option 4: Demonstrate an equivalent emission reduction as would 

be obtained under Compliance Option 3: 

This provision is similar to the current rule Section 5.1.3, but updated to meet the 

more stringent requirement of Option 3. This provides the operator the flexibility 

to use a variety of materials, as long as the emission reductions are equivalent to 

those that would be achieved by the fully controlling manufacturing and 

warehousing. Instead of controlling a storage warehouse, operators could either 

reduce those emissions earlier in the process with low-VOC materials or further 

reduce emissions during manufacturing. Since this requires equivalent emission 

reductions as the Option 3, staff believes that the District's rule is just as stringent 

as the SCAQMD rule. Rule language has been added for enforceability of this 

demonstration, similar to that described for Compliance Option 1. 

The SCAQMD rule is currently open for amendment to allow block molders to 

show rule compliance by controlling 93% of process emissions. Based on 

stakeholder comments, staff propose to add similar language to Rule 4682. The 

APCO would still have the right to require additional controls, should emissions 

be greater than those generated under Compliance Option 4. Because this 

option is not a mandatory compliance requirement and no additional emissions 

would result, staff do not consider this to be a significant change. 

1. Section 6.0 Recordkeeping – Section 6.1.3, which will be effective on and after (36 

months from rule adoption date), requires that records be retained 5 years instead of 

2 as currently required. Records are to be kept at the facility and be made available 

or submitted to the APCO, ARB, and EPA upon request. The change from the 

current two years to five years is based on a long-standing EPA policy and is being 

added to District rules as they are amended. 

2. Section 6.2 Test Methods – Provides for equivalent test methods to be used as 

approved by the APCO and EPA. Added Section 6.3 which lists the test method for 

collection device efficiency and Section 6.4 which list the test method for VOC 

content. 

3. Section 7.0 Compliance Schedule – New Section 7.3 stipulates the date where all 

operators are to be in compliance with all provisions of the rule. The final 
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compliance date will be 36 months from rule adoption date. This has proven to be a 

sufficient time in the past for operators to implement major changes that are need to 

comply with rule requirements. 

Significant issue raised at the September 20, 2007 Governing Board Hearing. 

During the public hearing for Rule 4682 an operator requested of the board a change in 

the rule language concerning the calculated averaging period. The operator specifically 

requested that the daily average VOC emissions be performed "monthly" or on a 

"calendar month" instead of a 30-day period. A monthly average would be in line with 

corporate practice and such a policy is consistent with Section 6.1.1 of the rule, is 

consistent with facility permit conditions, and would avoid the need to perform midmonth inventories. The Governing Board agreed that the request was reasonable and 

directed staff to make this change. 

EPA has commented that an averaging period greater than 24 hours would create an 

approvability issue unless certain conditions are met. EPA discusses these conditions 

in “Averaging Times for Compliance with VOC Emission Limits – SIP Revision Policy”, 

John O’Connor, US EPA – OAQPS Memorandum dated January 20, 1984. 

District staff identified, in the O’Connor memo, a set of criteria that must be fulfilled in 

order to maintain the monthly average. The five conditions and the District’s 

demonstrations are as follows. 

1. The VOC limits specified in an enforceable form with appropriate compliance 

dates. Rule 4682 Section 5.0 Requirements, Section 5.3.1, contains a VOC limit 

of 2.4 lbs per 100 lbs of total material processed. A compliance deadline of 

September 20, 2010 is specified in Section 7.0 Compliance Schedule. 

2. A description of the affected processes and associated historical production and 

operating rates. The Final Staff Report for Rule 4682 addresses affected 

processes and a current emissions inventory with reductions can be found in 

Appendix B. 

3. A description of the control techniques to be applied to the affected processes 

such as low solvent and waterborne coating; technology and/or add-on controls. 

The Final Staff Report for Rule 4682 in Section II C addresses control 

techniques. 

4. The nature of the emission control program whether a bubble, a regulation 

change, a compliance schedule, or some other form of alternative control 

program. Rule 4682 amendments include a VOC limit, and provisions for 

equivalency and can be found in the rule and the Final Staff Report. 
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5. The method of record keeping and reporting to be employed to demonstrate 

compliance with the new emission limit requirement and to support the showing 

that the emission limit is consistent with RFP and the demonstration of 

attainment. The recordkeeping requirement in Section 6.1 of Rule 4682 is 

consistent with EPA’s policy to keep and maintain records for at least five years. 

The rule also contains provisions for the maintenance of daily records of key 

operational characteristics to ensure compliance with the VOC emission 

requirements such as temperature, pressure, and flowrates. 

It is also important to note that violation of limits will be calculated consistent with the 

compliance period in accordance with Section 5.4. Due to operator concerns and 

variations in VOC content of the raw material based on supplier, temperature, and 

products manufactured, a monthly basis is justified. 

III. CURRENT EMISSIONS AND EMISSIONS REDUCTION 

As stated in the EOADP total VOC emissions from sources subject to Rule 4682 were 

estimated to be 0.3 tons per day in 2008. The plan also states that upon full 

implementation of this rule, less than 0.1 tons per day of VOC reductions are 

anticipated. The draft amendments to Rule 4682 seek to obtain as much reduction of 

VOC emissions from existing polystyrene foam, polyethylene, and polypropylene 

product manufacturing operations as expeditiously as practicable, technologically 

feasible, and economically reasonable, as determined by the District’s Governing 

Board. Based on the refined calculations shown in Appendix B, the final calculated 

emission reductions are 0.4 tons/day from a baseline of 1.4 tons per day. This 28% 

reduction meets the EOADP commitment of 26%. The refined calculated baseline was 

based on permitted emissions and throughputs and will be used to update the 

emissions inventory, as appropriate. 

IV. COST EFFECTIVENESS ANALYSIS 

District staff conducted a cost effectiveness analysis of the proposed rule in Appendix C. 

The cost information varies and may not represent actual costs, which will vary by facility 

depending on their existing control systems and chosen compliance method. Some 

facilities may be able to demonstrate compliance based on their current operations. Some 

facilities may be able to switch to low-VOC material at little or no additional cost. Some 

facilities that have existing covered warehouse areas might need to install a VOC control 

system and the costs may be higher depending on the size of the warehouse and the 

amount of stored finished products. Others that do not have an existing covered 

warehouse area, could incur a higher costs associated with building a warehouse and 

installing a VOC control system. Based on the high cost of building and controlling 

warehouses, it is unlikely that the rule would drive operators to that option unless some 
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other benefit would be derived from that option. The most likely option is believed to be 

the use of low-VOC materials and/or adding addition VOC controls to selected 

manufacturing areas. 

V. SOCIOECONOMIC ANALYSIS 

Pursuant to state law, District staff is required to analyze the socioeconomic impacts of 

any proposed rule or rule amendment that significantly affects air quality or strengthens an 

emission limitation. During the workshop meeting, District staff solicited volunteers from 

stakeholders and manufacturers and vendors of control devices to participate as members 

of the socioeconomic focus group for this rule. District staff worked closely with the focus 

group to determine direct compliance costs of the proposed rule. The socioeconomic 

focus group met in conjunction with the second workshop held in July 2007. The 

District’s independent consultant participated with the focus group to identify and analyze 

the socioeconomic impacts of the proposed rule. District staff used the socioeconomic 

analysis to further refine the rule. The socioeconomic report was published as an 

appendix to this staff report and may also be presented to the District Governing Board at 

the public hearing for adopting the proposed rule amendments in order to disclose any 

expected economic impacts. 

VI. ENVIRONMENTAL IMPACTS 

Pursuant to the California Environmental Quality Act (CEQA), District staff investigated 

the possible environmental impacts of the proposed amendments to Rule 4682. District 

staff has concluded that the proposed rule will not have any significant adverse effect on 

the environment. District staff recommends filing a Notice of Exemption under the 

provisions of Public Resource Code 15061 (b)(3). 

VII. RULE CONSISTENCY ANALYSIS 

Pursuant to the state Health and Safety Code, Section 40272.2, District staff has 

determined that Draft Rule 4682 is in harmony with, and not in conflict with or 

contradictory to, existing statutes, court decisions, or state or federal regulations that 

apply to the same type of equipment or source category. 

VIII. REFERENCES 

1. ARB BACT Clearinghouse Database. 

2. SJVUAPCD BACT Clearing House Database. 
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3. SJVUAPCD 1-hour Extreme Ozone Attainment Demonstration Plan, Amended 

October 2005. 

4. BAAQMD Regulation 8, Rule 52 (Polystyrene, Polypropylene, and Polyethylene 

Foam Product Manufacturing Operations. 

5. SCAQMD Rule 1175 (Control of Emissions from the Manufacture of Polymeric 

Cellular Foam Products)