ABSTRACT

The boiler and industrial furnace rule was published in the federal register on August 21, 1991 allowing 18 months for compliance testing. It was a self-implementing rule and everything was new. A draft technical amendment came out even as compliance tests were being conducted in the spring of 1992 but wasn’t published until 8-25-92, after the compliance deadline.

The hazardous waste combustor rule was published in the federal register on September 30, 1999 with compliance dates theoretically three years or more down the road. However, this time, a compliance test plan must be submitted a year in advance of the test in order to provide time for agency review. A technical amendment was published in the 7-10-2000 federal register, more technical amendments have been suggested and potential litigation has also been bantered about.

This paper will compare test plan requirements and options of the BIF rule, many tests of which have been conducted between 1991 & 2000, with the test plan requirements of the waste combustor rule (NESHAPS: Final Standards for Hazardous Air Pollutants for Hazardous Waste Combustors; Final Rule), no tests of which have yet been conducted. Several cement plants have submitted initial comprehensive performance test (ICPT) plans in order to achieve early compliance with the waste combustor rule.

INTRODUCTION

The boiler and industrial furnace rule was published in the federal register on February 21, 1991¹ allowing 18 months for compliance testing. It was a self-implementing rule and everything was new. A draft technical amendment came out even as compliance tests were being conducted in the spring of 1992 but wasn’t published until 8-25-92², after the compliance deadline.

The hazardous waste combustor rule was published in the federal register on September 30, 1999³ with compliance dates theoretically three years or more down the road. However, this time, a compliance test plan must be submitted a year in advance of the test in order to provide time for agency review. A technical amendment was published in the 7/10/00⁴ federal register and again on 11/09/00⁵. More technical amendments have been suggested and potential litigation has also been bantered about.

The Boiler and Industrial Furnace Rule

The boiler and industrial furnace (BIF) final rule had been published in the Federal Register on August 21, 1991 and compliance tests had to be completed by February 21, 1992. According to the Commercial BIF Compliance Test Results report published by Gossman Consulting, Inc., there were twenty-eight facilities that conducted emissions testing by the end of 1992 in compliance with the certification of compliance requirements of the BIF rule. Both operators and regulators learned a lot as a result of this testing. Another round of testing occurred approximately three years later as many of these same facilities conducted additional testing in order to comply with the three year recertification of compliance requirements of the BIF rule. Since that time, many facilities have gone through the RCRA permitting process and received their final Part B permits.

The BIF rule required that facilities demonstrate the ability to meet four nines destruction efficiency plus metals, carbon monoxide and hydrocarbon emissions limits. In demonstrating the ability to meet the BIF emission limits, facilities were required to set the following operational limits:

- maximum hazardous waste feedrate

- maximum gas flow rate

- minimum combustion chamber temperature

- maximum production rate

- maximum metals input rate (along with maximum combustion chamber temp)

- maximum chlorine input rate

- maximum inlet temperature to the ESP

- minimum kVA for ESP or minimum pressure drop at the baghouse

Operators were also required to keep their total hydrocarbons below 20 ppm and set a carbon monoxide maximum limit. In addition to setting these limits, each facility also had to establish automatic waste fuel cutoffs to insure that waste fuel was not being burned in the event that one of these limits was reached or exceeded.

At the time of the publication of the BIF rule in the Federal Register, the USEPA touted the rule as being very comprehensive and covering all the bases, particularly in regard to health protection of the public. According to the BIF preamble, “The Agency firmly believe[d] that the 0.08 [grains per dry standard cubic feet] PM standard, when used as a supplement to the risk-based metal controls provided by [the] rule, provides protection of human health and the environment.” (FR 56 7145, first column) The preamble also stated that “This standard is protective, it can be readily achieved by boilers and industrial furnaces, and it will ensure that the Agency’s controls are consistent for all combustion devices (boilers, industrial furnaces, and incinerators that pose similar risks. Hypothetical risk assessments have shown that a 99.99 percent DRE standard for POHCs is protective of risks posed by emissions of organic constituents in the waste in virtually every scenario of which the Agency is aware.” (FR 56 7146 right column) The BIF rule even took into account the health effects of indirect pathways, “the Agency believes that apportioning 75% of exposures to either indirect pathways or other emission sources (that can contribute to background levels) in the calculation of RACs [reference air concentrations] will help offset the contribution of indirect pathways. Another significant source of conservatism, offsetting the contribution of indirect pathways, is represented by the inherent uncertainty, and consequent conservatism, in the models used to estimate unit risk values. Use of the MEI in the Screening Limits procedure comprises yet another conservative element in the risk assessment process which would offset direct estimation of indirect pathway exposure.” (FR 56 7169 middle column) But apparently this was not enough for the Browner EPA. Additional regulatory pressure continued until the hazardous waste combustor MACT was finalized.

Hazardous Waste Combustor NESHAP/MACT

The NESHAPS: Final Standard for Hazardous Air Pollutants for Hazardous Waste Combustors; Final Rule was published in the Federal Register on September 30, 1999. This rule was/is unique in that it is designed to combine both Clean Air Act regulations with the Resource Conservation and Recovery Act. This effort of course includes Title V permits. The most obvious difference between the BIF rule and the HWC MACT rule is that operators only had 18 months to comply with the BIF rule whereas operators have up to three years (and conceivably four years) to comply with the HWC MACT rule. Required operational limits of the HWC NESHAP/MACT are as follows:

- analysis of each feedstream

§ this is much like BIF except that organic HAPs analysis is required

- determination of hazardous waste residence time

§ this is a new requirement as compared to BIF

- establish maximum chlorine input rate

- perform DRE determination which includes a minimum combustion chamber temperature, maximum flue gas flow rate or production rate and a maximum hazardous waste input

- dioxin/furan emissions must be determined which includes determining a maximum APCD inlet temperature, minimum combustion chamber temperature, maximum flue gas flow rate or production rate and a maximum hazardous waste feedrate

- establish a minimum kVa for an ESP or a minimum pressure drop for a baghouse for particulate control

- metals control includes establishing a maximum ESP inlet temperature, maximum metals input rate, maximum chlorine input and a maximum flue gas flow rate or production rate

- HCl/Cl₂ limits require establishing a maximum chlorine input rate and maximum flue gas flow rate or production rate

- the test plan has to be submitted at least one year in advance so that the Agency may review and comment and ultimately approve the plan (this is more like a trial burn requirement than a BIF test requirement)

The HWC NESHAP/MACT also requires that there be a continuous monitoring system plan and performance test; a start-up, shutdown and malfunction plan; and a feedstream analysis plan (similar to a waste analysis plan). The CMS plan and demonstration is a more complex version of the certification of the continuous emission monitors associated with the BIF rule. The start-up, shutdown and malfunction plan is a regulatory formalization of operational activities already in place at a facility but now the Agency has another reason to fine you for non-compliance.

Major Differences Between BIF and HWC NESHAP/MACT Testing Requirements

One major difference is that the waste combustor rule has grouped metals into semi-volatile (Cd & Pd) and low volatile (As, Be & Cr) and allows the use of one of the metals in each group as a surrogate for the other metals in the group. This reduces cost for metals spiking and makes the spiking of metals an activity that is much safer. However, particulate matter limits were lowered.

BIF allowed the use of data in lieu of doing another test in the event that similar data already existed. In the case of the HWC NESHAP/MACT, a variation on the data in lieu of provision has to do with allowing previous destruction efficiency test data. The operator can also petition the Agency for various other considerations in the comprehensive performance testing requirements.

Other significant issues include permission to extrapolate metals in order to set limits, and allowing weighted averaging of emissions in the case of in line raw mills where necessarily the in line raw mill is not operational 100% of the time that the kiln is operational. One particularly significant operational issue has to do with setting limits based upon the average of the averages of three runs versus the average of the maximum rolling hourly averages. This change requires that a kiln be pushed to the ragged edge over the entire run period, which may cause operational challenges.

A number of other requirements were deleted such as dropping barium and silver from any consideration and dropping the requirement for a maximum combustion chamber temperature limit. However, dioxins and furans have now been added to the Bevill/waste CKD analytical requirements. Since the advent of BIF, boilers and industrial furnaces have been required to demonstrate that their waste cement kiln dust (CKD) is not hazardous according to 40CFR266.112. Now they are just making it more costly.

In October of this year, 2001, hazardous waste burning cement plants will begin their initial comprehensive performance testing (ICPT) in accordance with HWC NESHAP/MACT. Between now and then, there will be review of the already submitted test plans, with lots of gnarling and gnashing of teeth over exactly what will end up in these ICPT Plans. Review and approval of these plans is new in comparison to BIF, although realistically, no facility in their right mind would have performed a BIF test that the Region didn’t generally approve of anyway. Of course there were all those enforcement actions that came on the heels of all those compliance efforts of the self-implementing BIF rule. Nonetheless, facilities that are either going through the Part B permitting process or have completed it are familiar with the review and approval process. Former EPA Administrator Carol Browner was anti-combustion, plain and simple. It will be interesting to see how things proceed under the new Administrator. Hopefully, boilers and industrial furnaces can now aim at one set target instead of chasing one around that keeps moving.

REFERENCES

1. Burning of Hazardous Waste in Boilers and Industrial Furnaces; Final Rule, Federal

2. Federal Register , vol. 57, August 25, 1992, pages 38557-38566.

3. NESHAPS: Final Standards for Hazardous Air Pollutants for Hazardous Waste

Combustors; Final Rule, Federal Register, Thursday, September 30, 1999, pages

52827-53077.

4. NESHAPS: Final Standards for Hazardous Air Pollutants for Hazardous Waste

Combustors; Final Rule; Technical Correction, FR65, July 10, 2000, pages 42292-

42302.

5. NESHAPS: Final Standards for Hazardous Air Pollutants for Hazardous Waste

Combustors; Final Rule; Interpretive Clarification and Technical Correction, FR65,

November 9, 2000, pages 67268-67272.

6. Gossman Consulting, Inc., Commercial BIF Compliance Test Plans Results, 1992.