DECORATIVE CHROMIUM AND ANODIZING NESHAP

• Applicability to the Chrome NESHAP
• Compliance Dates
• Emission Limits
• Work Practice Standards
• Performance Testing
• Monitoring
• Recordkeeping
• Reporting
• Air Permits
• Air Quality Fees
• Benefits of Compliance
• Where to go for Additional Help
• Definitions
• Summary of July19, 2004, Amendment
• Frequently Asked Questions

On January 25, 1995, the U.S. Environmental Protection Agency promulgated the National Emission Standard for Hazardous Air Pollutants for Chromium Emissions from Hard and Decorative Chromium Electroplating and Chromium Anodizing Tanks (Chrome NESHAP). Since then, the chrome NESHAP has experienced several amendments. All the amendments have been included in this guide. The chrome NESHAP affects all facilities that use chromium electroplating tanks, regardless of size. Activities your facility must do to comply with the Chrome NESHAP are dependent upon the size of the operation and the type of process (hard, decorative, or anodizing).

NOTE: This fact sheet will only focus on the issues that decorative, trivalent, and anodized chromium electroplaters need to address due to the chrome NESHAP.

The Chrome NESHAP is published in Title 40, Part 63, Subpart N of the Code of Federal Regulations (40 CFR 63). Contact the Michigan Department of Environmental Quality (MDEQ) Clean Air Assistance Program (CAAP) for information on how to obtain a copy of the chrome NESHAP. See “Where to Go for Additional Help” on page 8 of this guide.

In general, the NESHAP contains six requirements:

1. Emission limits
2. Work practice standards
3. Performance testing
4. Monitoring
5. Recordkeeping
6. Reporting

The specific requirements for each decorative chromium electroplating tank depend upon the type of chromium bath (trivalent or hexavalent) and if the facility is a major source or an area source.

If the decorative chromium electroplating tank uses a trivalent chromium bath that incorporates a wetting agent as a bath ingredient, then the electroplater is subject to the recordkeeping and reporting requirements, but is not subject to the work practice requirements discussed on page 3, or the continuous compliance monitoring requirements on page 4. Also, the wetting agent must be an ingredient in the trivalent chromium bath components purchased from the vendor (vs. the wetting agent being added to the bath components after purchase). If the wetting agent is manually added to the bath, then the facility is subject to all the requirements.

APPLICABILITY TO THE NESHAP

All chromium electroplating located at a facility performing decorative chromium electroplating is subject to the chrome NESHAP. However, a tank is exempt from the Chrome NESHAP if it meets one of the following conditions:

• No chromium electroplating is actually taking place in the tank (e.g., rinsing tanks, etching tanks, and cleaning tanks);
• No electrolytic process occurs in the tank (e.g., a chrome conversion coating tank where no electrical current is applied); or
• The tank is being used to conduct research or laboratory operations.

COMPLIANCE DATES

Existing tanks (initial startup on or before 12/16/93)
Existing chromium electroplating tanks had to comply with the Chrome NESHAP by January 25, 1997.

New tanks (initial startup after 12/16/93)
All new chromium electroplating tanks with an initial startup after January 25, 1995, are required to comply with the Chrome NESHAP immediately upon startup.

EMISSION LIMITS

The Chrome NESHAP specifies an emission limit of 0.01 milligrams/dry standard cubic meter that facilities can typically achieve by using a certain control and monitoring technique to reduce emissions. Demonstrating compliance with this emission limit is typically achieved through monitoring of the surface tension of the chromium electroplating tanks bath.

WORK PRACTICE STANDARDS

The Chrome NESHAP specifies that all facilities must prepare an operation and maintenance plan. However, decorative chromium electroplaters that use trivalent chromium with wetting agent in purchased bath do not have to prepare one. When developing this plan:

• Specify the operation and maintenance criteria for the tank, control technique, and monitoring equipment.
• Provide a checklist to document the operation and maintenance of the tank, control technique, and monitoring equipment.
• Incorporate work practice standards.
• Include a step-by-step procedure for identifying and correcting malfunctions.
• Specify procedures to be followed that will prevent malfunctions.

PERFORMANCE TESTING

Facilities subject to the Chrome NESHAP and demonstrating compliance with the 0.01 mg/dscm must conduct an initial performance test to demonstrate compliance with the emission limit standard. Facilities opting to demonstrate compliance using the surface tension limit are not subject to initial performance testing requirements.

This is a one-time test. Performance tests for new tanks with a startup date after January 25, 1995, must be conducted within 180 days after startup. Facilities must notify the Air Quality Division (AQD) of the MDEQ of the testing date at least 60 days before the test and must submit a testing protocol.
Facilities must conduct the initial performance test using certain test methods and procedures listed in the chrome NESHAP. Most facilities hire a testing service to conduct the test; however, the Chrome NESHAP allows facilities to perform their own testing. For additional information, contact the CAAP. See “Where to Go for Additional Help” on page 8 of this guide.

Following the initial performance test, a performance test report must be submitted to AQD that contains the following information:

• A description of the process
• Descriptions of the sampling locations
• Sampling and analysis procedures and any modifications to standard procedures
• Test results
• Quality assurance procedures and results
• Records of
  • Operating conditions during testing
  • Preparation of standards used during test
  • Calibration procedures
• • Raw data sheets for
  • Field sampling
  • Field and laboratory analysis
• Documentation of calculations
• Any additional information required by the test method

This report must be submitted to AQD within 90 days after your initial performance test.

MONITORING

Facilities must demonstrate continuous compliance by monitoring an operating parameter value for each control technique. This value links the control technique with the operating limit and is established during the initial performance test. Facilities must begin monitoring on the date of their initial performance test. Table 1 is a summary of the monitoring requirements.

Table 1. Summary of Monitoring Requirements

CONTROL TECHNIQUE	OPERATING PARAMETER	MONITORING FREQUENCY	OPERATING LIMIT
Composite mesh-pad (CMP) system	Pressure drop across the system	Daily	± 2" H2O
Packed-bed scrubber (PBS)	Inlet velocity pressure and Pressure drop across the system	Continuous and Daily	± 10% and ± 1" H2O
PBS/CMP system	Pressure drop across the system	Daily	± 2" H2O
Fiber-bed mist eliminator	Pressure drop across the fiber-bed mist eliminator and Pressure across the upstream control used to prevent plugging	Daily	± 1" H2O
Wetting agent-type fume suppressant	Surface tension	Every 40 hours of operation	35 dynes/cm with tensiometer 45 dynes/cm with stalagmometer
Foam blanket-type fume suppressant	Foam thickness	Hourly	1"
Other control device	To be proposed by facility	To be proposed by facility

* dynes/cm = dynes per centimeter; and
lbf/ft = pound-force per foot.

Surface Tension Monitoring

The surface tension shall be measured once every 4 hours during operation of the tank with a stalagmometer or a tensiometer as specified in Method 306B.

The time between monitoring can be increased if there have been no exceedances. The surface tension shall be measured once every 4 hours of tank operation for tfirst 40 hours of tank operation after the compliance date. Once there are no exceedances during 40 hours of tank operation, surface tension measurement may be conducted once every 8 hours of tank operation. Once there are no eduring 40 hours of tank operation, surface tension measurement may be conducted once every 40hours of tank operation on an ongoing basis, until an exceedance occurs. The minimum frequof monitoring allowed by this subpart is once every 40 hours of tank operation.

Once an exceedance occurs as indicated through surface tension monitoring, the original monitoring schedule of once every 4 hours must be resumed. A subsequent decrease in frequency shall follow the schedule laid out in the previous paragraph. For example, if an owner or operator had been monitoring an affected source once every 40 hours and an exceedance occurs, subsequent monitoring would take place once every 4 hours of tank operation. Once an exceedance does not occur for 40 hours of tank operation, monitoring can occur once every 8 hours of tank operation. Once an exceedance does not occur for 40 hours of tank operation on this schedule, monitoring can occur once every 40 hours of tank operation.

Once a bath solution is drained from the affected tank and a new solution added, the original monitoring schedule of once every 4 hours must be resumed, with a decrease in monitoring frequency allowed following the procedures addressed in the previous paragraph.

RECORDKEEPING

All facilities subject to the Chrome NESHAP must keep records to document compliance. The following records are required:

• Inspection records;
• Maintenance records;
• Malfunction records;
• Performance test results;
• Monitoring data;
• Excess emission records; and
• Process records, including the following:
  • Operating time for each chromium electroplating tank.
  • For tanks using fume suppressants, the date and time that fume suppressants are added.
  • For decorative chromium electroplating tanks using a trivalent bath, records of the bath components with the wetting agent clearly identified as a bath constituent contained in one of the bath components.

All records should be kept at the facility for at least five years. For sample recordkeeping forms, contact the CAAP. See “Where to Go for Additional Help” on page 8 of this guide.

REPORTING

Every facility subject to the Chrome NESHAP must fulfill several reporting requirements. Table 2 summarizes what reports are required for each facility and the reporting deadline. Send all reports to the AQD district office where the facility is located. For reporting forms, contact the CAAP. See “Where to Go for Additional Help” on page 8 of this guide.

Table 2. Summary of Reporting Requirements

TYPE OF REPORT	FACILITIES THAT MUST REPORT	REPORTING DEADLINE
Initial notification report	Existing tanks	July 24, 1995
	New and reconstructed tanks	No later than 30 days after construction or reconstruction began
Performance test notification	All facilities conducting initial performance tests	At least 60 days before the test
Performance test results	All facilities conducting initial performance tests	No later than 90 days after the test
Notification of initial compliance status	Facilities conducting initial performance tests	No later than 90 days after the initial performance test
	Facilities not required to conduct initial performance test	No later than 30 days after the compliance date
Ongoing compliance status report	Major sources	Complete twice a year, or four times a year if exceedances occur or if requested.
	Area sources	Complete once a year, or two times a year if exceedances occur or if requested.
Notification of construction or reconstruction	All facilities	As soon as practical before construction or reconstruction is planned to begin.
Notification of when construction or reconstruction is commenced	All facilities	Within 30 days of beginning construction
Notification of actual startup	All facilities	Within 30 days of startup
Notification of process change	All facilities	No later than 30 days after the process change

AIR PERMITS

Electroplating facilities should be aware of two different air permit programs: the New Source Review program and the Renewable Operating Permit (ROP) program. The AQD administers both programs.

Permit to Install Program

Rule 201 of the Michigan Administrative Rules for Air Pollution Control requires a person to obtain an air permit before installing, relocating, or modifying a process that may emit air contaminants. For permitting questions, contact the CAAP. See “Where to Go for Additional Help” on page 8 of this guide

Renewable Operating Permit (ROP) Program

A ROP consolidates all of a facility’s air quality requirements into one document. All major sources must apply for an ROP. A major source is a facility that emits or has the potential to emit 10 tons per year or more of any hazardous air pollutant (HAP) or 25 tons per year or more of any combination of HAPs.

All operations subject to the Chrome NESHAP will be subject to the ROP program. If the chromium electroplating operation by itself is a major source or if it is located at a major source, apply for an ROP according to the schedule in Michigan Rule 210. If the chromium electroplating operation is not located at a major source and is not a major source by itself, apply for an ROP by December 9, 2005. For assistance in determining applicability to the ROP program, contact the CAAP. See “Where to Go for Additional Help” on page 8 of this guide.

AIR QUALITY FEES

The AQD has the authority to collect an annual air quality fee. Facilities subject to the fee include major sources (subject to the ROP program) and facilities subject to a NESHAP.

Under the fee program, facilities that are subject to a NESHAP but are not major sources are required to pay an annual air quality fee. Facilities that are major sources for HAPs are required to pay a facility charge plus an emission charge per ton of air contaminants emitted.

BENEFITS OF COMPLIANCE

Compliance with the Chrome NESHAP will reduce the public’s exposure to hazardous air pollutants and keep chromium electroplating facilities operating within the law. Other incentives include:

• • Improving air quality
• • Reducing waste
• • Maintaining good public relations
• • Increasing worker safety

The Clean Air Act has strong enforcement provisions with both civil and criminal sanctions for violating the law.

WHERE TO GO FOR ADDITIONAL HELP

The Clean Air Assistance Program can provide copies of the chrome NESHAP, recordkeeping forms, and reporting forms. For questions regarding the Chrome NESHAP contact:

Clean Air Assistance Program
Environmental Science and Services Division
Department of Environmental Quality
P.O. Box 30457
Lansing, Michigan 49809-7957
800-662-9278
www.michigan.gov/deqair - Click on “Clean Air Assistance”

DEFINITIONS

Add-on air pollution control device: Equipment installed in the ventilation system of a chromium electroplating or anodizing tank for the purpose of collecting and containing chromium emissions from the tank.

Air pollution control technique: Any method, such as an add-on air pollution control device or a chemical fume suppressant, that is used to reduce chromium emissions from chromium electroplating and anodizing tanks.

Area source: Any facility that emits less than 10 tons per year of any individual hazardous air pollutant (HAP) and less than 25 tons per year of any combination of HAPs.

Bath component: The trade or brand name of each component in trivalent chromium plating baths. For trivalent chromium baths, the bath composition is proprietary in most cases. Therefore, the trade or brand name for each component can be used; however, the chemical name of the wetting agent contained in that component must be identified.

Chemical fume suppressant (or mist suppressant): Any chemical agent that reduces or suppresses fumes or mists at the surface of an electroplating or anodizing bath.

Chromium anodizing: The electrolytic process by which an oxide layer is produced on the surface of a base metal for functional purposes (e.g., corrosion resistance or electrical insulation) using a chromic acid solution.

Chromium anodizing tank: The receptacle or container along with the following accompanying internal and external components needed voltage adjustments, heat exchanger equipment, circulation pumps, and air agitation systems.

Chromium electroplating tank: The receptacle or container along with the following internal and external components needed for chromium electroplating: Rectifiers, anodes, heat exchanger equipment, circulation pumps, and air agitation systems.

Composite mesh-pad system: An add-on air pollution control device typically consisting of several mesh-pad stages. The purpose of the first stage is to remove large particles. Smaller particles are removed in the second stage, which consists of the composite mesh pad. A final stage may remove any re-entrained particles not collected by the composite mesh pad.

Decorative chromium electroplating: The process by which a thin layer of chromium (typically 0.003 to 2.5 microns) is electro-deposited on a base metal, plastic, or undercoating to provide a bright surface with wear and tarnish resistance. The chromium process can be hexavalent or trivalent.

Electroplating or anodizing bath: The electrolytic solution used as the conducting medium in which the flow of current is accompanied by movement of metal ions for the purpose of electroplating metal out of the solution onto a work-piece or for oxidizing the base material.

Emission limitation: The concentration of total chromium allowed to be emitted expressed in milligrams per dry standard cubic meter (mg/dscm) or the allowable surface tension expressed in dynes per centimeter (dynes/cm).

Enclosed hard chromium electroplating tank: A chromium electroplating tank that is equipped with an enclosing hood and ventilated at half the rate or less that of an open surface tank of the same surface area.

Existing tank: Any tank that has an initial startup date on or before December 16, 1993.

Fiber-bed mist eliminator: An add-on air pollution control device that removes contaminants from a gas stream through the mechanism of inertial impaction and Brownian diffusion.

Foam blanket: The type of chemical fume suppressant that generates a layer of foam across the surface of a solution when current is applied to that solution. Foam blanket additives do not normally reduce the surface tension of the solution.

Hard chromium electroplating or industrial chromium electroplating: A process by which a thick layer of chromium (typically 1.3 to 760 microns) is electro-deposited on a base material to provide a surface with functional properties such as wear resistance, a low coefficient of friction, hardness, and corrosion resistance.

Hexavalent chromium: The form of chromium in a valence state of +6.

Large hard chromium electroplating facility: A facility that performs hard chromium electroplating and has a maximum cumulative potential rectifier capacity equal to or greater than 60 million ampere-hours per year (amp-hr/yr).

Major source: A facility that emits or has the potential to emit 10 tons per year or more of any hazardous air pollutant or 25 tons per year or more of any combination of HAPs.

Maximum cumulative potential rectifier capacity: The summation of the total installed rectifier capacity at a hard chromium electroplating facility (expressed in amperes) multiplied by the maximum potential operation schedule of 8,400 hours per year multiplied by 0.7 (this assumes that electrodes are energized 70% of the total operating time).

New tank: Any tank with an initial startup date after December 16, 1993.
Open surface hard chromium electroplating tank: A chromium electroplating tank that is ventilated at a rate consistent with good ventilation practices for open tanks.

Operating parameter value: A minimum or maximum value established for a control device or process parameter that, if achieved by itself or in combination with one or more other operating parameter values, determines that an owner or operator is in continual compliance with the applicable emission limitation or standard.

Packed-bed scrubber: An add-on air pollution control device consisting of a single or double packed bed that contains packing media on which the chromic acid droplets impinge. The packed-bed section of the scrubber is followed by a mist elimination to remove any water entrained from the packed-bed section.

Rectifier: A device that converts alternating current into direct current by permitting a considerable flow of current in one direction.

Research or laboratory facility: Any facility whose primary purpose it to conduct research and development into new processes and products. Operated under the close supervision of technically trained personnel, this facility does not manufacture products for commercial sale.

Small hard chromium electroplating facility: A facility that performs hard chromium electroplating and has a maximum cumulative potential rectifier capacity of less than 60 million amp-hr/yr.

Surface tension: The property, due to molecular forces, that exists in the surface film of all liquids and tends to prevent liquid from spreading.

Trivalent chromium: The form of chromium in a valence state of +3.

Trivalent chromium process: The process used for electro-deposition of a thin layer of chromium onto a base material using a trivalent chromium solution instead of a chromic acid solution.

Wetting agent: The type of chemical fume suppressant that reduces the surface tension of a liquid.

SUMMARY OF JULY 19, 2004 AMENDMENT

On July 19, 2004, the National Emission Standards for Chromium Emissions from Hard and Decorative Chromium Electroplating and Chromium Anodizing Tanks (chrome NESHAP) was amended. These amendments are final, enforceable, and effective as of July 19, 2004. Five technical areas of the Chrome NESHAP were amended. They are:

1. The use of fume suppressants for controlling chromium emissions from hard chromium electroplating tanks.

2. A revised surface tension limit for decorative chromium electroplating tanks when measuring surface tension with a tensiometer.

3. An alternate emission limit for hard chromium electroplating tanks equipped with enclosing hoods.

4. Added definitions for chromium electroplating and chromium anodizing tanks.

• Chromium anodizing tank means the receptacle or container along with the following accompanying internal and external components needed voltage adjustments, heat exchanger equipment, circulation pumps, and air agitation systems.
• Chromium electroplating tank means the receptacle or container along with the following internal and external components needed for chromium electroplating: Rectifiers, anodes, heat exchanger equipment, circulation pumps, and air agitation systems.
• Enclosed hard chromium electroplating tank means a chromium electroplating tank that is equipped with an enclosing hood and ventilated at half the rate or less that of an open surface tank of the same surface area.
• Open surface hard chromium electroplating tank means a chromium electroplating tank that is ventilated at a rate consistent with good ventilation practices for open tanks.

5. Revised definitions for chromium electroplating and chromium anodizing processes.

• Stalagmometer means an instrument used to measure the surface tension of a solution by determining the mass of a drop of liquid by weighing a known number of drops or by counting the number of drops obtained from a given volume of liquid.
• Tensiometer means an instrument used to measure the surface tension of a solution by determining the amount of force needed to pull a ring from the liquid surface. The amount of force is proportional to the surface tension.

6. The pressure drop monitoring requirement for composite mesh pad (CMP) control systems.

NOTE: Within this publication we will address questions and answers associated with decorative chromium electroplating and chromium anodized tanks.

If you have any questions regarding the amended chrome NESHAP, contact the Clean Air Assistance Program (CAAP) at 1-800-662-9278.

FREQUENTLY ASKED QUESTIONS

I. AMENDMENTS (July 19, 2004)

What is the revised surface tension limit for decorative chromium electroplating tanks when measuring surface tension with a tensiometer?

The amended Chrome NESHAP has added a separate surface tension limit of 35 dynes/cm when using a tensiometer. The surface tension limit of 45 dynes/cm still applies when using a stalagmometer. If a facility chooses to continue to use a tensiometer, they may need to modify their Renewable Operating Permit (ROP)/Permit to Install (PTI) if it contains a reference to the 45 dynes/cm tension limit. Also, if a facility chooses to continue to use a tensiometer, they will be required to demonstrate compliance with the surface tension limit through the continuous compliance monitoring required by paragraph 63.343(c)(5)(ii). The facility will be required to establish compliance by measuring the surface tension once every 4 hours during operation of the tank for the first 40 hours of tank operation. If there have been no exceedances, the time between monitoring can be increased to once every 8 hours for 40 hours of tank operation. Again, if there are no exceedances, the time between monitoring can be increased to once every 40 hours of tank operation on an ongoing basis.

What are the revised definitions for chromium anodizing and chromium electroplating tanks?

The definition of affected source has been amended to include the peripheral equipment, such as rectifiers and anodes that is essential for the chromium electroplating process.

The tank replacement of existing affected sources is considered routine maintenance and was not intended to be treated as reconstruction and potentially subject to emission limits for new sources. The definitions are as follows:

Chromium anodizing tank means the receptacle or container along with the following accompanying internal and external components needed for chromium anodizing: rectifiers fitted with controls to allow for voltage adjustments, heat exchanger equipment, circulation pumps, and air agitation systems.

Chromium electroplating tank means the receptacle or container along with the following internal and external components needed fro chromium electroplating: rectifiers, anodes, heat exchanger equipment, circulation pumps, and air agitation systems.

What is the pressure drop monitoring requirement for composite mesh pad (CMP) control systems?

The amendment increased the allowable range of pressure drops from ±1” to ±2” for the requirement for establishing the operating limit for any source controlled with a CMP to demonstrate compliance with the Chrome NESHAP.

If a facility chooses to use the ±2”, a new performance test may be required to establish the new operating limit. See 40 CFR 63.343 for specific information pertaining to this requirement.

If the facility has a Permit to Install (PTI) with the requirement of the ±1”, the facility will be required to have the PTI modified before using the ±2” operating limit

II. APPLICABILITY TO THE CHROME NESHAP

What is the difference between “new” and “existing” tanks?

“New” chromium electroplating tanks means all chromium electroplating tanks that were constructed, reconstructed or installed after December 16, 1993. All facilities with an initial startup after December 16, 1993, but on or before January 25, 1995, were to comply with the emission limit standards, by January 25, 1995. All facilities with an initial startup after January 25, 1995, are required to comply with the emission standards immediately upon startup.

“Existing” tanks means all chromium electroplating tanks that were constructed, reconstructed or installed on or before December 16, 1993. “Existing” hard chromium electroplating should have been in compliance with the emission limit standards by January 25, 1997.

Are research and lab operations exempt from compliance with the NESHAP rule?

Yes, they are exempt. Other exemptions are as follows:

Process tanks associated with a chromium electroplating or chromium anodizing process, in which neither chromium electroplating nor chromium anodizing is taking place in the tank (e.g., rinse tanks, etching tanks and cleaning tanks).

Tanks that contain a chromium solution in which no electrolytic process occurs (e.g., chrome conversion coating tank where no electrical current is applied).

Facilities that perform chromium passivating.

Is phosphating subject to this NESHAP rule?

No.

The only chrome plating I do at my facility is plating tools as part of a tool maintenance operation. Is my facility considered exempt?

No. If a chromium electroplating operation is used to plate maintenance tools, it is an affected facility.

How is decorative chrome defined in the regulation?

This term is described in 40 CFR 63.341 of subpart N and is as follows:

Decorative chromium electroplating means the process by which a thin layer of chromium (typically 0.003 to 2.5 microns) is electrodeposited on a base metal, plastic, or undercoating toprovide a bright surface with wear and tarnish resistance. In this process, the part(s) serves as the cathode in the electrolytic cell and the solution serves as the electrolyte. Typical current density applied during this process ranges from 540 to 2,400 Amperes per square meter (A/m2) for total plating times ranging between 0.5 to 5 minutes.

In decorative hexavalent chrome electroplating, what approximate percent of the overall mists emitted into the air is hexavalent chromium?

The majority, if not all, of the emissions are hexavalent chromium.

III. COMPLIANCE DATES

Where is more information available regarding extensions of compliance deadlines? Who reviews and decides on requests for extensions?

The general provisions of NESHAP addresses requests for extensions; specifically, 40 CRF 63.61(1) Subpart A. Michigan has full delegation of authority to implement and enforce the standard. Contact your local MDEQ, AQD district office.

IV. EMISSION LIMITS

I understand decorative chromium platers are not required to use fume suppressants. If they choose to use suppressants in addition to scrubbers, are they required to check the surface tension regularly?

Yes, only if both are required to meet the emission limit in the chrome NESHAP. If you only need the scrubbers to comply with the emission limit, then only monitor parameters associated with the scrubbers. However, if you have a Permit to Install for this process, most likely the permit will require operation of the scrubber and monitor the surface tension.

Do you retain liability from the date of compliance to the date you test your source? If so, would suggest testing prior to the compliance date?

You are out of compliance if you do not test within 180 days after the compliance date and show compliance.

Paragraph 2 of section 63.342(e) infers that a facility can use a trivalent bath without an incorporated wetting agent. If this is true, is it possible that a facility using a trivalent bath could manually add a wetting agent to the trivalent bath?

Yes, though manually adding a wetting agent to the trivalent bath requires demonstration of compliance with the surface tension monitoring and emission limits outlined in 40 CFR 63.342(d)(2).

If you have different types of plating tanks (affected sources and non-affected sources) vented to a common control device, how do you calculate your emission limit?

Multiple source emission limits are described in 40 CRF 63.344(e) of the subpart N (pages 4971 and 4972) of the January 25, 1995, Federal Register notice.

V. PERFORMANCE TESTING

Can I perform my own initial performance testing?

Yes. The regulation contains USEPA Reference Methods 306 and 306A which are used to measure the chromium concentration discharged to the atmosphere. The California Air Resources Board (CARB) Method 425 may also be used to measure chromium emission as long as the analytical requirements listed in the regulation are adhered to. Alternate test methods may also be used as long as they have been validated using USEPA Reference Method 301. To obtain a video of how to conduct a Method 306A test, contact Robin Segall, Emission Measurement Center, Office of Air Quality Planning Standards, USEPA, at 919-541-0893.

If I am using a foam blanket-type fume suppressant, what are the testing requirements?

A facility must stack test to meet an emission limit unless specifically exempt under 40 CFR 63.343(b)(2). The facility must determine the appropriate foam thickness during a stack test or choose minimum values contained within the standard. The facility will then monitor for this parameter.

If a facility has several chrome plating facilities in numerous states, does each individual tank have to be stack tested, or can they apply one or more tests to the remaining facility locations?

Each individual tank must be stack tested unless exempted from the chrome NESHAP.

When measuring emissions, does one measure the hexavalent chromium amount or the total chromium?

You can measure either hexavalent chromium or total chromium. The analysis used to measure hexavalent chrome is different than the one used to measure the total chromium.

The accuracy of USEPA Method 306-A has been described as plus or minus 50%. Would it be wise to do an initial test using this method to get in the ball park, and then use Method 306 to show final compliance?

When USEPA Methods 306-A and 306 are done properly, the results should be the same with a narrow range of error. Method 306-A has never been described as plus or minus 50%; it is just as accurate as Method 306. The plus or minus 50% is in reference to the early work done on the standard where the USEPA wanted a screening method that was plus or minus 50%. That screening method was never developed.

When stack testing is done to establish the operating parameter for a control device, does the magnehelic gauge (differential pressure device) display a range of several inches during the test?

No. The magnehelic gauge may display a range of several tenths of an inch of water, not several inches.

Should the facility perform multiple stack tests during multiple operating conditions?

If a facility has multiple operating conditions, the facility should demonstrate compliance under worst case operating conditions.

What is the effect on air flow and volume by using composite mesh pad at the end of the system?

A composite mesh pad functions as a restriction at the outlet so airflow will decrease. The increase in pressure drop may require a higher fan capacity.

VI. MONITORING

The final rule requires a facility to maintain records of the chrome electrolytic plating tank operating time. When does a tank’s operating time begin; when the tanks are initially heated, or when they are being used and current is applied?

When the tanks are being used and current is applied.

As I understand it, I must monitor the surface tension of the chrome electrolytic plating tank once every four hours. Is this every four hours of plating tank operating time or every four hours the plating line is in operation?

Every four hours of plating tank operating time.

A facility that uses a wetting agent to maintain surface tension in their chrome bath operates for only five minutes a day. To comply with the continuous compliance requirements of the rule, the initial monitoring frequency must occur once every four hours of tank operation for the first 40 hours of tank operation. How should they monitor to maintain compliance?

The rule requires that they monitor the bath once every four hours for the first forty hours of tank operation. Given that they only operate the tanks five minutes a day:

4 hours = 240 min.
240 min./5 min. = 48 days

Technically, they should monitor a minimum of once every 48 days. However, for quality assurance aspects, monitoring the surface tension before each operation is recommended.

How much variation will be accepted in an operating parameter?

An affected source may establish a range of compliant operating parameter values, or may set as the compliant value, the average value over three test runs of once performance test. For example, in a composite mesh pad system, a ±2 inch of water column from the pressure drop value (average described above) may be accepted. In a packed-bed scrubber system, a ±2 inch of water column from the pressure drop value and ±10 percent from the velocity pressure value may be accepted as the compliant range. See 40 CFR 63.343(c)(1-7).

I am not familiar with the stalagmometer. How do I get more information about how to use this instrument?

Call the MDEQ’s Environmental Science and Services Division, Clean Air Assistance Program, at 800-662-9278, for names of vendors. Vendors should be able to explain the instrument’s use.

VII. REPORTING

Does the notification of construction requirements pertain solely to those tanks with an initial startup after January 25, 1995?

Yes. The notification of intent to construct or reconstruct must be submitted before construction or reconstruction begins.

Are facilities required to submit reports to both the USEPA and the MDEQ?

No, only to the MDEQ. Any information requested by the USEPA will be supplied by the MDEQ unless otherwise stated.

To whom do I submit my Initial Notification Form?

Submit your form to the local MDEQ, AQD district office.