WENATCHEE WORKS

REVISED SEPTEMBER 8, 2008

National Emission Standards for Hazardous Air 

Pollutants for Primary Aluminum Reduction Plants

Alcoa

Wenatchee Works

POTLINE PRIMARY EMISSION CONTROL SYSTEM

Start up, Shut Down, and Malfunction Plan

Prepared by:

Alcoa

6200 Malaga Hwy.

Malaga, WA 98828

Revision 3

September 8, 2008
 WENATCHEE WORKS

REVISED SEPTEMBER 8, 2008

TABLE OF CONTENTS

PAGE

TABLE OF CONTENTS i

1.0 INTRODUCTION 1

2.0 START UP PLAN 2

3.0 SHUT DOWN PLAN 3

4.0 MALFUNCTION PLAN 4

LOW AIR FLOW

LOW ALUMINA FLOW

MAINTENANCE OF CONTINUOUS MONTORING SYSTEM

LOSS OF POTLINE POWER FOR AN EXTENDED PERIOD

CATASTROPHIC FAILURE OF FUME CONTROL EQUIPMENT 

VISIBLE EMISSION PLAN
 WENATCHEE WORKS PAGE 1 REVISED JANUARY 26, 2005

NOTE: All revisions to this plan are to be retained for five (5) years from their date of issue.

1.0 INTRODUCTION

This Startup, Shutdown, Malfunction Plan meets the requirements of the Primary Aluminum 

NESHAP. This plan contains procedures to be used during periods of startup, shutdown, and 

malfunction as well as procedures for corrective action for the primary control devices of potlines 

1 – 3 and potline 5 at Wenatchee Works. This plan will be made available to the permitting 

authority upon request. The startup, shutdown, and malfunction plan does not need to address 

any scenario that would not cause the source to exceed and applicable emission limitation in the 

relevant standard (40 CFR Part 63.6(e)(3)).

If this plan is followed, the semi-annual report will note that it was followed. Any action taken by 

the owner or operator during a startup or shutdown that caused the source to exceed any 

applicable emission limitation in the relevant emission standards, or malfunction (including actions 

taken to correct a malfunction) is not consistent with the procedures specified in the affected 

source’s startup, shutdown, and malfunction plan, the owner or operator shall report the actions 

taken for that event within 2 working days after commencing actions inconsistent with the plan, 

followed by a letter within 7 working days after the event (40 CFR 63.10(d)(5)(2). 

The semi-annual report must note when the SSM Plan has been revised. Revisions to the plan 

are to identify revised procedures for operating and maintaining the source during SSM events 

and a program of corrective action for similar events in the future. Revisions to this plan must be 

retained for 5 years. 

Corrective actions for any SSM event must be initiated within 1 hour per 63.848(h). 

Failure of a parameter to meet the parametric limit is an exceedance. The 7th exceedance on a 

fume control device parametric in the semi-annual reporting period will result in a violation. Both 

exceedances and violations must be reported on the semi-annual report
 WENATCHEE WORKS PAGE 2 REVISED JANUARY 26, 2005

NOTE: All revisions to this plan are to be retained for five (5) years from their date of issue.

2.0 START UP PLAN

A start-up or re-start is defined as the process of re-energizing an idled section(s) of aluminum 

reduction cells that is serviced by a common Fume Control System(s) (device). The start-up 

begins when the first idled reduction cell is energized. The start-up concludes 180 days following 

start-up or after all pots have become stabilized, which ever occurs first. Stabilization parameters 

are defined in the potroom operating control practice.

2.1 Potlines 1-3 with A-398 Control Systems and potline 5 with GTC Injector System

1. The Operator is to assure that prior to adding liquid bath to the first pot, a fluidized bed of 

alumina has been established in an A-398/GTC compartment. The Operator is 

responsible for starting alumina flow and airflow to the appropriate number of A-398/GTC 

compartments to ensure that the ratio of operating pots to operating A-398/GTC 

compartments does not exceed 18:1. 

2. In the event of a complete cold start up (i.e. no other pots operating at the site, the 

operator may operate up to 6 pots without operating an A-398 / GTC compartment for no 

longer than 60 hours to entrain heat and facilitate the melting of bath in the first operational 

pots.

3. During start-ups of potline portions, the operator is to assure that the ratio of pots 

operating to A-398/GTC compartments on line does not exceed 18:1. The operator is to 

also assure that operating parameters during the start-ups of potline portions do not fall 

below the lower limits computed from the ratio of operating pots to the total pot count in 

the potline. The limits will be determined and compared using the calculations below on a 

daily basis:

Minimum Number of GTC Compartments =

18

Number ⋅ of ⋅Operating ⋅Cells

When the computed values are ≤ 1.0, the number of scrubbers to be operated is 1. Values greater than whole numbers 

shall be rounded to the next larger whole number (e.g. 1.1 = 2 A-398/GTC Compartments).

( ) ( )

(Number of Total Pots in Line)

Potline Parametric Limit Number of Operating Pots in Line Parametric value s ⋅ ⋅ ⋅ ⋅ ⋅

⋅ ⋅ × ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ( ) =

4. The Start-Up is to be logged in the SSM Log. 

5. Records of the start-up are to be retained for five (5) years. 
 WENATCHEE WORKS PAGE 3 REVISED JANUARY 26, 2005

NOTE: All revisions to this plan are to be retained for five (5) years from their date of issue.

3.0 SHUTDOWN PLAN

A shutdown is defined as the process of having the liquid contents of bath and aluminum solidify 

for all of the aluminum reduction cells that are serviced by a common Primary Control Device. 

The shutdown begins when electrical power has been intentionally discontinued for the purpose of 

a shutdown, or 24 hours after a sustained unintentional loss of electric power. The shutdown 

concludes 48 hours after service of electrical power has been discontinued.

Appropriate limits for parametrics during a shutdown will be determined from the ratio of pots 

operating to total pot count in the potline. The operator is to assure that operating parameters 

during the shutdowns of a potline or portions of a potline do not fall below the lower limits 

computed from the number of operating pots in the potline. The limits will be determined and 

compared using the calculations below on a daily basis:

Number of Operating Fume Control Devices =

18

Number ⋅ of ⋅Operating ⋅Cells

When the computed values are ≤ 1.0, the number of scrubbers to be operated is 1. Values greater than whole 

numbers shall be rounded to the next larger whole number (e.g. 1.1 = 2 A-398 Compartments).

( ) ( )

(Number of Total Pots in Line)

Potline Parametric Limit Number of Operating Pots in Line Parametric value s ⋅ ⋅ ⋅ ⋅ ⋅

⋅ ⋅ × ⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ( ) =

If only a portion of the potline served by a single control device is shut down, the operator will 

again target the ratio of pots operating to fume control compartments to be 18:1 or less for all 

potlines.

3.1 Shutdown Actions

1. The Operator is to assure that throughout the shutdown, sufficient emission controls are 

kept operating such that a minimum ratio of 18:1 or less operating cells to control devices 

is maintained for all potlines. 

2. The Operator may shut down A-398/5W-GTC compartments any time after the 48-hour 

period, because the liquid contents of the reduction cells will be frozen and gaseous 

emissions will cease after 48 hours without electrical power.

3. The Operator is responsible for completing the SSM log. 

4. Records of the shutdown are to be retained for five (5) years
 WENATCHEE WORKS PAGE 4 REVISED JANUARY 26, 2005

NOTE: All revisions to this plan are to be retained for five (5) years from their date of issue.

4.0 MALFUNCTION PLAN

4.1 Low Air Flow

Low airflow is defined as airflow conditions that generate a pot cycle (48hours) average CFM 

lower than the parametric limit. It is determined by comparison of the average CFM for each fume 

control device over the potroom cycle to the established parametric . The parametric limit for a 

fraction of a potline running will be the normal parametric limit divided by the fraction of the potline 

running. .

Examples of low air flow conditions may include, but are not limited to, loss of electrical power, 

major bearing failure or unplanned compartment outages that result in simultaneous multiple 

compartment downtime within the control device.

 

4.1.1 Corrective Actions:

1. The Operator is to log the time that he/she first became aware of the exceedance and the 

time at which he/she initiated the corrective action. 

2. The Operator is to confirm the system status, noting which component(s) are either off line or 

otherwise impaired. 

3. The Operator is to notify appropriate maintenance personnel or restart the component(s). 

4. Personnel responding are to make repair(s), equipment replacement(s), or process change(s) 

to remedy the situation in a safe, efficient, and timely manner.

5. The Operator is responsible for completing the SSM log. 

6. Records are to be retained for five (5) years. 

4.2 Low Alumina Flow

Low alumina flow is defined as alumina flow conditions that generate a pot cycle (48hours) total 

alumina feed or rotary vane feeder run time lower than the parametric limit. It is determined by 

comparing the fume control device rotary vane feeder total tons of alumina or run time in minutes 

during the potroom cycle to the limit. The parametric limit for a fraction of a potline running will be 

the normal parametric limit divided by the fraction of the potline running. 

Examples of activities or conditions contributing to low alumina flow conditions may include, but 

are not limited to; motor failure; motor control failure; drive assembly failure; secondary ore feed 

components; unexpected failure of the primary air gravity conveyor (a.k.a.- feed air slide) or one of 

its components such as the canvas membrane or the primary blower and reductions in alumina 

flow due to unplanned outages.

4.2.1 Corrective Actions:

1. The Operator is to log the time that he/she first became aware of the exceedance and the 

time at which he/she initiated the Corrective Action . 

2. The Operator is to confirm the system status, noting which component(s) are either off line or 

otherwise impaired.

3. The Operator is to notify appropriate maintenance personnel or restart the component(s). 

4. Personnel responding are to make repair(s), equipment replacement(s), or process change(s) 

to remedy the situation in a safe, efficient, and timely manner.

5. The Operator is responsible for completing the SSM log. 

6. Records are to be retained for five (5) years. 
 WENATCHEE WORKS PAGE 5 REVISED JANUARY 26, 2005

NOTE: All revisions to this plan are to be retained for five (5) years from their date of issue.

4.3 Malfunction of Continuous Monitoring System 

Malfunctions could include power interruptions, PLC/PC malfunctions, and PLC- PC 

communication problems. 

4.3.1 Corrective Actions:

1. The Operator is to log the time that he/she first became aware of the exceedance and the 

time at which he/she initiated the Corrective Action.

2. The Operator is to confirm the system status, noting which component(s) are either off line or 

otherwise impaired.

3. The Operator is to notify appropriate maintenance personnel or restart the component(s). 

4. Personnel responding are to make repair(s), equipment replacement(s), or process change(s) 

to remedy the situation in a safe, efficient, and timely manner. 

5. The Operator is responsible for completing the SSM log. 

6. Records of the repair of the continuous monitoring system are to be retained for five (5) 

years.

4.4 Loss of Potline Power for an extended period

A malfunction may cause the entire potline to be de-energized for an extended period of time. In 

this situation, the fume control device may be shut down to conserve heat in the smelting cells. 

Under this situation, DC power to the pots is lost but AC power to the reactors is available. ,It may 

be decided very early on after DC power is lost (i.e. within an hour) to shutdown the control device 

to conserve heat. This is justified under the general duty clause since keeping the potline running 

even under this scenario would cause less emissions than allowing the potline to run cold, then 

going through a long cold restart process. The latter may take up to 180 days before the potline 

returns to stable operations. 

4.4.1 Corrective Actions:

1. Following the request to idle the fume control device, the Operator will stop the fans and 

alumina flow for the reactor compartments. 

2. The Operator is responsible to begin startup of reactor compartments in a safe, efficient, and 

timely manner following the re-energization of the potline. 

3. Normal operation is to be attained as soon as possible following the SOPs for startup of the 

compartments.

4. The Operator is responsible for completing the SSM log. 

5. Records of the malfunction are to be retained for five (5) years.

4.5 Catastrophic Failure of Fume Control Equipment

A catastrophic failure of the fume control equipment is considered a malfunction. Examples of 

catastrophic failure may include, but are not limited to; collapse of a unit inlet duct, a direct 

lightning strike, a loss of electrical power, an earthquake, a tornado, or a system fire that results in 

uncontrolled emissions. 

4.5.1 Corrective Actions:
 WENATCHEE WORKS PAGE 6 REVISED JANUARY 26, 2005

NOTE: All revisions to this plan are to be retained for five (5) years from their date of issue.

1. The operator is to log the time that the condition was first noticed or reported and log the time 

at which he/she first began to respond.

2. As soon as the situation has become stable and hazards have been cleared, the Operator is 

to confirm the system status, noting which fume treatment system components are either off 

line or otherwise impaired. 

3. The Operator is to notify appropriate maintenance, engineering and support personnel.

4. Personnel responding are to make repair(s), equipment replacement(s), or process change(s) 

to remedy the situation in a safe, efficient, and timely manner.

5. The Operator is responsible for completing the SSM log. 

6. Records of the malfunction are to be retained for five (5) years.

4.6 Visible Emissions

Typical visible emissions are defined as the presence of visible emissions indicative of abnormal 

fume control device operation during the required daily visible emissions check. 

4.6.1 Corrective Actions:

1. The Operator is to report the dusting stack(s) from MACT sources during the daily visual 

checks made by the Operator.

2. The Operator is to log the time that he/she first noticed or was notified of the condition and 

also log the time which he/she initiated this plan. 

3. The Operator is to shut down the appropriate compartment to make repairs.

4. Personnel responding are to make repair(s), to remedy the situation in a safe, efficient, and 

timely manner.

5. The Operator is responsible for completing the SSM log. This will include logging the time, 

date, duration, any actions taken beyond the scope of this plan, and initials or signature.

6. Records of the visible emissions are to be retained for five (5) years.

Revisions:

Revision Date Description Initials

Rev. 0 09-09-99 Original HMV

Rev. 1 07-05-00 Revised to include Potline 3 HMV

Rev. 2 01-26-05 Revised to include better description of startup, 

shutdown procedures

RJL

Rev. 3 09-08-08 Revised to incorporate changes in SSM requirements KAK