ENGINEERING EVALUATION REPORT

PLANT NAME United States Mint

APPLICATION NUMBER 19110

PLANT NUMBER 5474

DATE 11

- 13

- 2008

1. BACKGROUND

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

Chromium Plating and Chro mic 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 sourc es

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 Contr ol Abatement

- 1 Abatement

- 2

8 16712 16712 Floating Balls A

- 2 Mapco

Enforcer III A

- 3 HEPA

9 “ “ “ “ “

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

criteria, enumerated in Reg 2

- 1

- 403:

**Permit Conditions:** Exce pt 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 wh ich 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 devic es 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 1,4 00,000 0.006 0. 0 185

Post

- ATCM 1,4 00,000 0.0015 0. 0 0463

Net Difference 0 0.0045 0. 0 14

3. CEQAAN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

2 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 T ECHNOLOGY

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 ris ks were less than 10 in a million at the

previous emission level, 0.0185 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 16712 is presented in this application, as is the revised

Condition 16712

.

10. RECOMMENDATIONS

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

Condition 16712

.

OLD CONDITION 16712

COND# 16712

--------------------------------------

1. Annual Usage

The total annual (net) throughput

from chrome plating tanks S

- 8 and S

- 9

shall not exceed 1.4 millionAN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

3 ampere

- hours in any consecutive

twelve

- month period.

(Basis: Voluntary Toxic Risk Reduction)

2. Abatement

This source shall not be operated

unless a layer of floating plastic

balls is maintained in the bath in

accordance with manufacturers

instructions and all chrome plating

tank emissions are vented through

A

- 2 Mapco Enforcer III Mist

Eliminator System and A

- 3 HEPA

Filtration Unit. All emissions

shall be exhausted from P

- 4 emission

point. The abatement system shall be

well maintained and kept in good

operating condition.

(Basis: Toxic Risk)

3. Emission Limits

Emissions of hexavalent chromium

shall not exceed 0.0045 milligram per

ampere

- hour (mg/a

- hr) after abatement.

(Basis: Toxic Risk)

4. Source Test

Compliance Source Test: To demonstrate

compliance with condition 3 above,

the US Mint must perform a

District

- approved source test (according

to a District approved protocol) on

the exhaust stack within 60 days of

permit approval. 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.

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.

[Basis: Reg 8 Rule 16 (d)]

5. Parameter Monitoring

a) To demonstrate compliance with

Condition 1, above, the US Mint

shall instal l, operate and maintain

a continuous recording,

non

- resettable ampere

- hour meterAN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

4 that operates on the electrical

power lines connected to the tank

rectifier. A separate meter

shall be hard

- wired for each rectifier

if applicable.

[Basis: Reg 8 Rule 16 (e)(1)]

b) The US Mint shall continuously

monitor the pressure drop across

A

- 2 Mist Eli minator System. 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 across A

- 2

mist eliminator s ystem shall

be maintained within the range of 2.1

and 4.1 inches of water.

[Basis: Reg 8 Rule 16 (e)(2),

Compliance Source Test dated 3/20/2001]

c) The US Mint shall continuous ly

monitor the pressure drop across

A

- 3 HEPA Filtration Unit. 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 across

the HEPA Filtration System shall be maintained

within the range of 0.6 and 2.6 inches water.

[Basis: Reg 8 Rule 16 (e)(2),

Compliance Source Test dated 3/20/200 1]

6. Inspection/Maintenance

[Basis: Reg 8 Rule 16 (f)(1)]

a) The US Mint shall perform visual

inspections of A

- 2 Mist

Eliminator System and A

- 3 HEPA

Filtration Unit at a frequency

of at least one time per

calendar quarter. This visual

inspection is to ensure that

there is proper drainage, no

unusual chromic acid buildup on

the pads, and no evidence of chemical

attack that would affect the

structural integrity of the devices.

b) US Mint shall visually inspect the

back portion of the mesh pad closest

the stack at a frequency of at least

one time per quarter to ensure

there is no breakthrough of chromic

acid mist.AN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

5 c) US Mint shall visual inspect du ctwork

from tank to the control device at

a frequency of at least one time

per calendar quarter to ensure there

are no leaks.

d) US Mint shall perform washdowns

of the mist eliminator system at

a frequency as recommended by the

manufacturer.

e) The ampere

- hour meter shall be

installed and maintained a s per

manufacturer's recommendations.

7. Operation and Maintenance Plan

[Basis: Reg 8 Rule 16 (g)]

a) US Mint shall prepare an operation

and maintenan ce (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

stand ardized 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: US Mint shall

keep the written operation and

maintenance plan on record after it

is developed to be made available

for District inspection, upon request.

c) Changes to the O & M plan: Any

changes made to the O & M Plan

should document in an addendum

to the plan. In addition,

US Mint 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 year after each revision

to the plan.

d) Revisions to address breakdowns:

The O & M Plan shall be revised as

necessary to minimize breakdowns.AN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

6 To satisfy the inspection and

maintenance procedures, US Mint 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

[Basis: Reg 8 Rule 16 (h)]

The following records shall be kept

and maintained by US Mint for at least

five years total; and at least two

years on site.

a) Inspection rec ords for A

- 2 Mist

Eliminator System and A

- 3 HEPA

Filtration Unit: US Mint 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 co ntrol system (i.e. ductwork,

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

taken to correct deficiencies found

during inspection.

b) US Mint shall maintain records to

demonstrate that the inspection and

maintenance requirements of Condition

6, above, have been satisfied.

c) Performance test records: US Mint

shall maintain test reports docum enting

the conditions and results of all

performance tests.

d) Monitoring data records: US Mint

shall maintain records of monitoring

data as required by Co nditions 1 and

5, as follows:

e) Breakdown records: US Mint shallAN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

7 maintain records of the occurrence,

duration, and cause (if known) and

action taken o n each breakdown.

f) Records of excesses: US Mint shall

maintain records of exceedances of:

a) the emission limitation identified

in Condition 3; b) the monitoring

para meter 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 (i f known), and where possible,

the magnitude of any excess emissions.

9. Reporting

a) On an annual basis, US Mint 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.

[Basis: Reg 8 Rule 16 (i)(3)(2)]

b) B reakdown reports: US Mint shall

report breakdowns as required by the

District breakdown procedures

identified in Regulation 1.

[Basis: Reg 8 Rule 16 (i)(4)]

NEW CONDITION 16712

COND# 16712

- -------------------------------------

The owner/operator shall comply with the following

Conditions for Sources 8 and 9 Chrome Plating Tanks.

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:AN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

8 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 combined throughput at

S

- 8 and S

- 9 shall not exceed 1.4 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

an d 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

- 8 and S

- 9 with plating tank

emissions vented through A

- 2 Mapco Enforcer III

Mist Eliminator Unit, A

- 3 HEPA Filtration Unit,

and exhausted from P

- 4 Emission point.

The ventilation and abatement system shall be properly

maintained and kept in good working condition.

b) Mechanical fume suppressant: The owner/operator uses a

layer of float ing plastic balls to assist in fume

suppression prior to downstream abatement. A

sufficient number of floating plastic balls shall be

maintained on the plating bath liquid surface such that

when the bath is non

- ope rational, the entire exposed

liquid surface area is covered with at least one layer

of balls. The interstitial areas between the adjacent

plastic balls and other areas of the bath surface area

occupied with plating parts or bath equipment shall not

be considered to be part of the liquid surface in need

of being covered with balls.[Basis: 93102.9(f)]

3. Source Test

a) The owner/opera tor 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 comp liance with this part, as long as

the existing source test was conducted in

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

[Basis: 93102.7(a)(1)(A)]

b) The owner/operator shall perform sour ce tests to

demonstrate compliance according to the following

schedule:

i. Unless Part 3.b)ii. is satisfied, subsequentAN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

9 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 th e 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 origina l 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 sh all 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 conducti ng any source

test for compliance. This source testing protocol

shall include testing methods, length of sample

period, plating facilities to be operated during the

source test, sampling equipment and me thods, 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 duri ng the source

testing period:

i. Bath coverage

- floating balls: visually estimate

percent bath coverage prior to start of bath

operation (when bath is quies cent).

ii. A

- 2 Pressure Drop: record pressure drop at

least one time every 15 minutes of operation.

iii. A

- 3 Pressure Drop: record pressure drop at

least one time every 15 minutes of operation

.AN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

10 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]

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) a re

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:

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

s olution 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 e very 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, grin ding or polishing areas shall be

separated from the chrome plating operation by a

physical barrier, which may include, but is notAN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

11 limited to vertical plastic strip curtains.

g) Chromium containing w astes 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 i nstalled 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

- 2 Pressure Drop: The owner/operator shall

continuously monitor the pressure drop across A

- 2

Mapco Enforcer III unit. The pressure drop shall be

maintained within plus or minus 2 inches of water of

th e 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) A

- 3 Pressure Drop: The owner/operator shall

continuously monitor the pressure drop across A

- 3

HEPA filter. The pressure drop shall be maintained

with in minus 1⁄2 times to +2 times the inches of water

of the value established during the most recent

source test to demonstrate compliance. Pressure

drop readings shall be recorded at a frequency of at

least one time per operating week.

[Basis: 93102.9(b), 93102.12(c)(2)]

d) The owner/operator shall visually inspect the

electroplating bath for coverage of floating plastic

balls comparable to th e coverage observed during the

performance test. Visual inspections shall be

conducted and recorded at a frequency of at least

one time per operating day. [Basis: 93102.9(f)]

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 r evisions 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:AN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

12 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 inspectio n, 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 equipm ent 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, a nd any

actions taken to correct deficiencies found during

the inspection.

9. Recordkeeping

The owner/operator shall maintain the follo wing 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.

b) The owner/operator shall:

[Basis: 93102.12]

i. Record the percent coverage of floating

plas tic balls at least one time per

operating day

- prior to bath operation.

ii. Record monthly and cumulative 12

- month

rectifier ampere

- hour totals, and

iii. Record the pressure drop acros s the

abatement device(s) at least once per

operating week,

c) Breakdown Records noting the occurrence,AN 19110/U.S. Mint (Plant A5474)

RE Frazier, P.E.

11/13/2008

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

d) Records of excesses of the emission limitations

set forth in Part 1 or the monitoring parameters

established under Part 6 noting any exceedances of

the ampere

- hour throughput or pressure drop limits.

e) Housekeeping Records demonstrating compliance

with Part 3, above, including date and time of

housekeeping activity.

10. Reporting

a) S ource 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 s ource 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 re quest, 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 re port.

[Basis: 93102.13(c)]