ENGINEERING EVALUATION REPORT

PLANT NAME Roll Technology West

APPLICATION NUMBER 19111

PLANT NUMBER 7546

DATE 11-13-2008

1. BACKGROUND

On October 24, 2007, a major revision to the Airborne Toxic Control Measure (ATCM) for 

Chromium Plating and Chromic Acid Anodizing became law in California. As a result, the permit 

conditions for the District chrome platers (there are no chromic acid anodizers operating in the 

BAAQMD) need to be revised to address these changes. Following is a listing of the sources 

involved and the current and revised condition numbers. The ATCM can be found at the following 

website: http://www.arb.ca.gov/toxics/atcm/chroatcm.pdf

Source Old Cond New Cond Bath Control Abatement-1 Abatement-2

1 8641 8641 Fumetrol 140 A-1 Mapco 

Enforcer III

n/a

District regulations allow the APCO to make changes of permit conditions, based on certain 

criteria, enumerated in Reg 2-1-403:

Permit Conditions: Except as to permit applications reviewed in accordance with

Section 2-1-311, the APCO may impose any permit condition that he deems

reasonably necessary to insure compliance with federal or California law or District

regulations. For any permit application which was reviewed as a ministerial project in

accordance with Section 2-1-311, the APCO shall only impose permit conditions as

set forth in the District's Permit Handbook for the type of source being permitted. The

APCO may require the installation of devices for measurement or analysis of source

emissions or ground-level concentrations of air contaminants.

The proposed condition changes are to ensure compliance with the Chrome Plating ATCM, 

revised 10-24-2007.

2. EMISSION CALCULATIONS

The new permitted emission level will be 0.0015 mg/a-hr. Hence the following shows the 

permitted hex chrome emission rates before and after the permit condition modification.

Basis Throughput, a-hr/yr Factor, mg/a-hr Emissions, lb/yr

Current 35,000,000 0.006 0.4626

Post-ATCM 35,000,000 0.0015 0.1156

Net Difference 0 0.0045 0.347

3. CEQA
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Since the change of conditions will result in a decrease in the permitted emission levels, this 

application is exempt from CEQA review per Reg 2-1-312.1.

4. BEST AVAILABLE CONTROL TECHNOLOGY

Emissions are decreasing, therefore BACT is not applicable.

5. EXEMPTIONS

There are no applicable exemptions.

6. OFFSETS

Offsets are not applicable, since emissions decrease, therefore no offset triggers are exceeded.

7. TOXIC EVALUATION

Permitted emission levels decrease, therefore no toxic evaluation is required. Previous toxic risk 

evaluations have been conducted showing there are no significant risks to any member of the 

public from these operations. It should be noted that the risks were less than 10 in a million at the 

previous emission level, 0.4626 lb/yr. We would therefore expect the risk at the new control level 

to remain below 10 in a million.

8. STATEMENT OF COMPLIANCE

The purpose of revising the permit conditions is to ensure that the facility complies with the newly 

revised air toxic control measure.

9. CONDITIONS

The previous version of Condition 8641 is presented in this application, as is the revised Condition 

8641.

10. RECOMMENDATIONS

Issue a Change of Condition letter for the aforementioned sources, subject to the revised 

Condition 8641.

OLD CONDITION 8641

 COND# 8641 --------------------------------------

 1. Annual Usage 

 The total annual (net) throughput

 from chrome plating tank S1 shall

 not exceed 35 million ampere-hours

 in any consecutive twelve-month
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 period. 

 2. Abatement 

 This source shall not be operated

 unless all chrome plating tank

 emissions are vented through A1

 MAPCO Enforcer III Chrome Scrubber.

 All emissions shall be exhausted at

 a height of at least 43 feet

 (13 meters) above grade. The abatement

 system shall be well maintained and

 kept in good operating condition. 

 3. Emission Limits 

 Emissions of hexavalent chromium

 shall not exceed 0.006 milligram per

 ampere-hour (mg/a-hr) after abatement. 

 4. Source Test 

 Biennial Source Test: To assist in

 demonstrating ongoing compliance with

 permit condition 3 above, Roll

 Technology West shall perform a source

 test (according to a District approved

 protocol) at a frequency of not less

 than once every 24 months after the

 previous source test. 

 Source Testing Protocol: A written

 source test protocol shall be

 submitted for District approval prior

 to conducting any source test for

 compliance. This source test protocol

 shall include testing methods, length

 of sample period, plating facilities

 to be operating during the source test,

 sampling equipment and methods,

 parameters to be monitored, as well

 as the planned date for the source test.

 For the purpose of establishing an ongoing

 compliance parameter, the scrubber

 pressure drop shall be monitored and

 recorded at a frequency of at least

 once every 15 minutes during the source

 testing period. 

 All source tests used to demonstrate

 compliance shall determine the mass

 emissions of both total and hexavalent

 chromium in g/hr, mg/a-hr, and mg/dscm

 as emitted after abatement. Source

 tests shall be conducted while both
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 the chrome plating tank and chrome

 evaporation unit are operating

 simultaneously. A complete report

 shall be submitted to the District's

 Source Test Manager within 60 days of

 the source test and shall demonstrate

 compliance with Condition 3, above. 

 5. Parameter Monitoring 

 a) To demonstrate compliance with

 Condition 1, above, RTW shall

 install, operate and maintain a

 continuous recording, non-resettable

 ampere-hour meter that operates

 on the electrical power lines

 connected to the tank rectifier.

 A separate meter shall be

 hard-wired for each rectifier if

 applicable. 

 b) RTW shall continuously monitor

 the pressure drop across A1 MAPCO

 Enforcer III Scrubber. The gauge

 shall be located so that it can be

 easily visible and in clear sight

 of the operation or maintenance

 personnel. The pressure drop shall

 be maintained within plus or minus

 2 inches of water of the value

 established during the performance

 test to demonstrate compliance with

 the emission limitation.

 Pressure drop readings shall be

 recorded at a frequency of at

 least one time per operating day. 

 If the pressure drop is found to lie

 outside the range of acceptability

 RTW shall cease chrome plating as

 soon as practicable and take all

 appropriate measures to either

 bring the scrubber operation back

 into the range of acceptability or

 to otherwise demonstrate compliance

 with the emission limitation. 

 6. Inspection/Maintenance 

 a) RTW shall perform visual

 inspections of the A1 MAPCO

 Enforcer III Scrubber at a

 frequency of at least one time

 per calendar quarter.

 This visual inspection is to
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 ensure that there is proper

 drainage, no unusual chromic

 acid buildup, and no evidence of

 chemical attack that would affect

 the structural integrity of the

 devices. 

 b) RTW shall visually inspect the

 back portion of the scrubber

 closest the stack at a

 frequency of at least one time

 per quarter to ensure there is no

 breakthrough of chromic acid mist. 

 c) RTW shall visually inspect the

 ductwork from tank to the control

 device at a frequency of at least

 one time per calendar quarter to

 ensure there are no leaks. In the

 event a leak is discovered, it shall

 be repaired as soon as practicable. 

 d) RTW shall perform washdowns of

 the Enforcer III Unit at a

 frequency as recommended by the

 manufacturer. 

 e) The ampere-hour meter shall be

 installed and maintained as per

 manufacturer's recommendations. 

 7. Operation and Maintenance Plan 

 a) RTW shall prepare an Operation

 and Maintenance (O & M) plan.

 The plan shall incorporate the

 inspection and maintenance

 requirements as noted in

 Condition 6, above, and shall

 include the following elements:

 a) a standardized checklist to

 document the operation and

 maintenance of the source, the

 add-on air pollution control

 devices, and the process and

 control system monitoring equipment,

 and b) procedures to be followed

 to ensure that equipment is

 properly maintained. 

 b) O & M plan retention: RTW shall

 keep the written operation and

 maintenance plan on record after

 it is developed to be made

 available for District inspection,
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 upon request. 

 c) Changes to the O & M plan: Any

 changes made to the O & M Plan

 should be documented in an addendum

 to the plan. In addition, RTW

 shall keep previous versions of

 the O & M Plan on record to be

 made available for District

 inspection upon request, for a

 period of 5 years after each

 revision to the plan. 

 d) Revisions to address breakdowns:

 The O & M Plan shall be revised

 as necessary to minimize breakdowns. 

 To satisfy the inspection and

 maintenance procedures, RTW may use

 applicable standard operating

 procedure (SOP) manuals,

 Occupational Safety and Health

 Administration (OSHA) plans, or

 other existing plans, provided

 the alternative plans meet the

 requirements of this subsection. 

 8. Recordkeeping 

 The following records shall be

 kept and maintained by RTW for

 at least five years total; and

 at least two years on site. 

 a) Inspection records for A1 MAPCO

 Enforcer III Scrubber: RTW shall

 maintain inspection records to

 document that the Inspection/

 Maintenance requirements and the

 O & M Plan as required by

 Conditions 6 and 7, above,

 respectively have been met. The

 record can take the form of a

 checklist and should identify

 1) the device inspected, 2)

 the date and time of the inspection,

 3) a brief description of the

 working condition of the device

 during inspection, 4) maintenance

 activities performed on the

 components of the air pollution

 control system (i.e. ductwork,

 filter pad, fan, etc), and 5) any

 action taken to correct deficiencies

 found during inspection. 
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 b) RTW shall maintain records to

 demonstrate that the inspection

 and maintenance requirements of

 Condition 6, above, have been

 satisfied. 

 c) Performance test records:

 RTW shall maintain test reports

 documenting the conditions and

 results of all performance tests. 

 d) Monitoring data records: RTW

 shall maintain records of

 monitoring data as required

 by Conditions 1 and 5, as

 follows: 1) monthly and annual

 records of ampere-hour throughput,

 and 2) records of A1 MAPCO

 Enforcer III Scrubber pressure

 drop monitoring results. 

 e) Breakdown records: RTW shall

 maintain records of the occurrence,

 duration, and cause (if known) and

 action taken on each breakdown. 

 f) Records of excesses: RTW shall

 maintain records of exceedances

 of: a) the emission limitation

 identified in Condition 3; b)

 the monitoring parameter values

 of Condition 5; c) any site-specific

 operating parameters established

 for alternative equipment. The

 records shall include the date of

 the occurrence, the duration, cause

 (if known), and where possible,

 the magnitude of any excess

 emissions. 

 9. Reporting 

 a) On an annual basis, RTW shall

 prepare a summary report to the

 District to document the ongoing

 compliance status. This report

 shall be made available to the

 District upon request. 

 b) Breakdown reports: RTW shall

 report breakdowns as required by

 the District breakdown procedures

 identified in Regulation 1.
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NEW CONDITION 8641

COND# 8641 --------------------------------------

 The owner/operator shall comply with the following

 Conditions for Source 1 Chrome Plating Tank.

 Basis refers to either BAAQMD Regulations/Rules

 or California Code of Regulations, Title 17, Section

 93102 - 93102.16 and associated appendices, unless

 otherwise noted. 

 1. Performance Standards 

 a) Emission Limits effective through 10-23-2009: 

 Emissions of hexavalent chromium shall not exceed

 0.006 mg per ampere-hour (mg/amp-hr) after abatement.

 [Basis: 93102.4(a)(1)] 

 b) Emission Limits effective 10-24-2009: 

 Emissions of hexavalent chromium shall not exceed

 0.0015 mg per ampere-hour (mg/amp-hr) after abatement.

 [Basis: 93102.4(b)(1) 

 c) Throughput: The total annual throughput shall not

 exceed 35 million ampere-hours in any consecutive

 12-month period. [Basis: 93102.4(b)(1)] 

 d) The requirements of Parts 1a and 1b of this condition

 and the O&M Plan provisions do not apply during periods

 of equipment breakdown, provided the provisions of the

 District's breakdown rules are met. [Basis: 93102.2(b)]

 2. Abatement 

 a) The owner/operator shall abate at all times during

 operation of S-1 with plating tank emissions vented

 through A-1 Mapco Enforcer III Scrubber. All emissions

 shell be exhausted at a height of at least 43 feet

 (13 meters) above grade. [Basis: 93102.4(b)] 

 The ventilation and abatement system shall be properly

 maintained and kept in good working condition. 

 b) The owner/operator uses Fumetrol 140 chemical fume

 suppressant bath additive to assist in housekeeping

 efforts around the plating tank. The plating bath

 surface tension shall not exceed 45 dynes/centimeter

 if measured with a stalagmometer, or 35 dynes/centimeter

 if measured with a tensiometer.

 [Basis: 93102.9(d)(2)] 

 3. Source Test 
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 a) The owner/operator shall perform a source test by

 October 24, 2009 to demonstrate compliance with the

 emission performance standard specified in part 1b. 

 An existing District-approved source test may be used

 to demonstrate compliance with this part, as long as

 the existing source test was conducted in

 accordance with ATCM Section 93102.7(b) & (c).

 [Basis: H&S Code 93102.7(a)(1)(A)] 

 b) The owner/operator shall perform source tests to

 demonstrate compliance according to the following

 schedule: 

 i. Unless Part 3.b)ii. is satisfied, subsequent

 source testing shall be performed no later

than 36 months after the date of the previous

 District-approved source test demonstrating

 compliance.

 ii. If the previous two consecutive source tests

 demonstrate compliance, the subsequent tests

shall be performed no later than 48 months

after the previous source test.

 iii. If a source test demonstrates non-compliance,

 then the owner/operator must perform another

source test to demonstrate compliance.

Subsequent source tests to demonstrate

compliance shall be performed no later than

24 months after the previous source test. If

after two consecutive source tests at the 24

month frequency, both of which demonstrate

compliance, the source test frequency reverts

to the original schedule in Part 3.b)i. 

 c) Non-compliant source test: After conducting a

 source test which demonstrates non-compliance the

 owner/operator shall review and adjust or repair the

 plating operation and associated emission control

 system. A source test to demonstrate compliance

 shall be performed no later than 30 days after the

 chrome plating system adjustments/repairs are

 completed. 

 d) Any chrome plating bath that is non-operational at

 the time a source test is due does not have to be

 tested at that time. Upon subsequent start-up of

 any such bath, a source test shall be conducted

 within 30 days. 

 e) Source Testing Protocol: A written source test

 protocol based on 93102.7(c) shall be provided for

 District approval prior to conducting any source

 test for compliance. This source testing protocol

 shall include testing methods, length of sample
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 period, plating facilities to be operated during the

 source test, sampling equipment and methods, as well

 as the planned date for the source test. 

 For the purpose of maintaining ongoing compliance,

 the following parameters shall be monitored and

 recorded at the listed frequency during the source

 testing period: 

 i. Bath surface tension: one time, before tank

 operation commences.

 ii. A-1 Pressure Drop: record pressure drop at

 least one time every 15 minutes of operation. 

 f) The owner/operator shall contact the District Source

 Test Section at least 14 days in advance of the

 source test or as directed by the ATCM to obtain

 approval of the test protocol. The owner/operator

 shall notify the District Source Test Section at

 least 7 days in advance of each scheduled source

 test. [Basis: 93102.7] 

 g) If the owner/operator chooses to switch to a

 different bath additive, the plating tank must

 be re-source tested within 30 days to demonstrate

 compliance with the applicable Part 1 limit(s). 

 4. Training 

 No later than October 24, 2009, and within every two

 calendar years thereafter, the owner or operator shall

 ensure that hexavalent chrome based plating operations

 (including environmental compliance/recordkeeping) are

 under the direction of the owner or operator or current

 employee who is onsite and has completed the ARB

 Compliance Assistance Training Course for chrome

 plating and anodizing. [Basis: 93102.5(b)] 

 5. Housekeeping 

 The following housekeeping requirements shall be

 implemented to reduce potential hexavalent chrome

 fugitive emissions: [Basis: 93102.5(c)] 

 a) Chromic acid materials shall be stored in a closed

 container in an enclosed storage area. 

 b) Chromic acid materials shall be transported from

 storage to the bath in a closed container. 

 c) Any liquid or sold hexavalent chrome containing

 material that is spilled shall be contained or

 cleaned up within one hour after being spilled. 

 d) Dragout shall be minimized by: 
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 i. handling the plated parts so that chromic acid

 is not dripped outside the tank, and

 ii. installing splash guards at the tank to

 minimize overspray and to ensure that chrome

solution is returned to the tank. 

 e) Surfaces within the chrome storage area and the

 walkways and other areas potentially contaminated

 with hexavalent chrome, shall be cleaned at least

 one time every seven days by either HEPA vacuuming,

 damp cloth hand wiping, wet mopping, use of non-

 toxic dust suppressants or any other District-

 approved method. 

 f) Buffing, grinding or polishing areas shall be

 separated from the chrome plating operation by a

 physical barrier, which may include, but is not

 limited to vertical plastic strip curtains. 

 g) Chromium containing wastes generated as a result of

 any of the above housekeeping activities shall be

 stored, disposed of, recovered, or recycled using

 practices that minimize fugitive dust. 

 6. Monitoring 

 a) Each rectifier shall be hard-wired to a single non-

 resettable meter which records ampere-hours

 continuously during rectifier operation. Each

 ampere-hour meter shall be installed and maintained

 per manufacturer's specifications. The

 owner/operator shall record the total ampere-hours

 used during each month.

 [Basis: 93102.10(a), 93102.12(c)(1)] 

 b) A-1 Pressure Drop: The owner/operator shall

 continuously monitor the pressure drop across A-1

 Mapco Enforcer III Scrubber. The pressure drop

 shall be maintained within plus or minus 2 inches of

 water of the value established during the most

 recent source test to demonstrate compliance with

 the emission limitations of Part 1. Pressure drop

 readings shall be recorded at a frequency of at

 least one time per operating week.

 [Basis: 93102.9(b), 9102.12(c)(2)] 

 c) Surface Tension Monitoring: In order to demonstrate

 compliance with Part 2.b), above, the surface

 tension shall be initially measured and recorded

 daily for 20 operating days. If there is no

 exceedance of the surface tension limit during the

 initial 20 operating day tests, the measurement

 frequency may be automatically extended to one time

 per calendar week of operation. If an exceedance
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 occurs, the measurement frequency shall return to

 daily for 20 operating days, and weekly thereafter.

 [Basis: 93102.12(c)(4)(B)] 

 7. Operation & Maintenance (O&M) Plan 

 The owner/operator shall prepare an operation and

 maintenance plan for the chrome plating operation,

 which shall be retained onsite and made available for

 inspection upon request. Any revisions to the O & M

 Plan shall be documented in an addendum and all

 versions shall be maintained for a period of 5 years

 after each revision to the plan. The O&M Plan shall at

 a minimum include: 

 a) The inspection and maintenance requirements for the

 air pollution control equipment and amp-hr

 meters/totalizers. [Basis: 93102.11] 

 b) A checklist to document the inspection, operation

 and maintenance for the chrome plating operation,

 including steps to be taken to correct operating

 deficiencies. [Basis: 93102.11] 

 8. Inspection & Maintenance Frequency 

 a) The owner/operator shall perform visual inspections

 of the abatement systems and associated ductwork

 pursuant to ATCM Section 93102.10(a) at least once

 per calendar quarter and conduct wash downs of the

 Mapco Enforcer III unit per manufacturer

 recommendations. [Basis: 93102.10(a) and Reg 2-5] 

 b) In order to demonstrate compliance with Part 8a,

 the owner/operator shall record the equipment being

 inspected, date, brief description of the working

 condition of the device during the inspections, any

 maintenance activities performed on the components

 of the air pollution control systems, and any

 actions taken to correct deficiencies found during

 the inspection. 

 9. Recordkeeping 

 The owner/operator shall maintain the following records

 for at least five years, with the most recent two years

 maintained onsite. 

 a) Inspection Records to demonstrate that such

 inspections were done in accordance with the

 provisions of Section 93102.10 and the O&M Plan.

 Such records can take the form of a checklist and

 shall identify the devices inspected, the date and

 time of the inspection, a brief description of the

 working condition and any corrective actions. 
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 b) The owner/operator shall:

 [Basis: 93102.12] 

 i. Record the plating bath surface tension

 according to the testing frequencies noted

in Part 6.c), and

 ii. Record monthly and cumulative 12-month

 rectifier ampere-hour totals.

 iii. Record A-1 Mapco Scrubber pressure drop

 at least once per operating week. 

 c) Breakdown Records noting the occurrence,

 duration, cause (if known), and action taken. 

 d) Records of excesses of the emission or ampere-hour

 limits of Part 1, the surface tension

 limits of Part 2, or the pressure drop limits

 established under Part 6.b). 

 e) Housekeeping Records demonstrating compliance

 with Part 5, above, including date and time of

 housekeeping activity. 

 10. Reporting 

 a) Source Test Reports: The owner/operator shall

 report source test results used to demonstrate

 compliance to the District Source Test Section no

 later than 60 days after the test date. The content

 of the source test reports shall contain the

 information identified in Appendix 1 of the

 applicable ATCM. Source test records shall be

 maintained onsite at the facility and made available

 to the District upon request, for a period of 5

 years from the date of the source test.

 [Basis: 93102.13(a)] 

 b) Annual Compliance Status Report: The owner/operator

 shall submit an annual compliance status report to

 the District on or before February 1, and shall

 include the following information for the preceding

 calendar year. 

 The content of the ongoing status shall include the

 information identified in Appendix 3 of the

 applicable ACTM. The report shall contain the name,

 title and signature of the responsible official who

 is certifying the accuracy of the report.

 [Basis: 93102.13(c)]