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Gossman Consulting, Inc.


Volume 3, Number 05                  A Gossman Consulting, Inc. Publication                    May, 1997

Air & Waste Management Association Boiler and Industrial Furnace Conference

Jim Woodford

The 1997 A&WMA BIF Conference was productive again this year. The overriding theme heard from both industry and regulators was communication with the public and getting public input into the permitting process in particular. Rest assured that regulators are going to insure that public input opportunities increase. Attendees also heard extensively about trial burn experiences. Interestingly enough, there seemed to be something very positive yet elusively different about this year's conference. When queried about this, Henry Winders of Continental Cement Company, LLC rattled off what seemed to accurately sum things up by pointing out that the presentations this year were ones about having been there and having increased confidence in the data. I would have to agree. Hopefully, this will lead to greater understanding from the agency, more so from headquarters than the regions. The regions are in the trenches just like industry and they truly are caught between several rocks and several hard places. Hopefully, the rest of the regions will jump on the pragmatic cooperation band wagon found in Region VII.

The keynote address for the 1997 A&WMA BIF Conference (Waste Combustion in Boilers and Industrial Furnaces) scheduled to be given by Dennis Grams, Regional Administrator for USEPA Region VII, was not given as scheduled. Dennis was stuck at an airport. John Smith, USEPA Region VII, and Walter Greer of Ash Grove Cement stood in for him by giving their Wednesday luncheon presentation. This actually worked in favor of the success of the conference. What better way to kick things off than with a presentation from two of the major players in accomplishing the first ever hazardous waste burning cement kiln (BIF) permit in the country.

John Smith pointed out that he knew regulators were sometimes not very well received at conferences like the BIF conference. So in order to prepare himself, he said, he downloaded all the information from the Gossman Consulting, Inc. WEB pages. This brought a round of laughter from the attendees and got the conference off on a lighter note. John talked about the experience of finalizing the Ash Grove permit and summarized his talk with a review of the lessons learned: (1) it is a delicate balancing act to provide information to the public without alarming them; (2) the citizens usually understand the process; (3) what it is like to live around a cement plant; (4) adding additional sampling as justified by the risk assessment; (5) Region VII is in the process of expanding public input; (6) meetings for permits since then have been sporadically attended; and finally, (7) no matter how hard you try to issue a good permit, it is quite a learning process to sit across from someone who is genuinely concerned about the issues.

Walter Greer then followed with his half of the presentation. Walter started off by saying that it had been a long process, and he felt "...that it [was] a pleasure and an honor to share the podium with John [Smith], one of the best of the jack-booted thugs at EPA." He pointed out that while initially being excited about Region VII paying for their risk assessment, in the end he advised attendees to pay for their own risk assessment. It turned out that Ash Grove was denied direct involvement in the risk assessment and ended up with an unsatisfactory risk assessment because "All of the risk assessment calculations and methodologies were not fully disclosed." and there is still strong suspicion that "errors remain". Walter also talked about the high level of cooperation in the European Union and how the permitting process was much simpler and less confrontational. He appealed to the EPA to work towards making the permitting process in the United States more like the permitting process in the European Union.

In general, they ended up with a pretty good permit although Ash Grove felt their restrictions were too tight and that they were being required to do unnecessary testing. "In a world where the EPA can use omnibus authority, unilateral strategies and unpromulgated policies to make up the rule as it goes along, the permit conditions could have been a lot worse." Walter complimented John Smith for having done the best job under the circumstances.

A question from the audience, to John Smith, asked whether he felt that he was better prepared now to handle the more vivid imagination questions in future permitting efforts. John's response was that he had learned much, but that you have to address public concerns no matter what. John was supported by Fred Chanania from the USEPA Office of Solid Waste in Washington, D.C. who was in the audience. His comment was that his experience had been that you can always place your trust in the public. If there is participation by those who have vivid imaginations and can never be satisfied, the public usually recognizes this and goes about their business.

Following the exhibition break, Session 1 began and was chaired by Rex Jameson of Holnam Inc. The first speaker was Fred Chanania of USEPA's Office of Solid Waste in Washington D.C. He provided a synopsis of the upcoming NODA on the proposed HWC rule. Fred was followed by Craig Campbell of CKRC. His talk was entitled, "Control of Emissions from Cement Kilns Burning Waste Derived Fuel: What is Achievable." Craig presented summaries of the extensive data that had been collected, analyzed and presented to EPA. Much of the data was quite familiar to the cement industry, but Craig's overall point was that CKRC felt they had provided sufficient data to EPA to merit re-evaluation of their regulatory efforts.

The next speaker was Liane Hetherington-Ward from Safety-Kleen. Her talk was entitled, "The Effect of MACT on the Industry Surrounding the Burners." Safety-Kleen services the small quantity generator and her talk focused on how MACT will result in significantly increased disposal prices for these businesses who may ultimately seek disposal alternatives to combustion, including those with negative impacts on the environment.

Randy Jones of TXI gave the final talk before the break. Characteristically, his talk was low key. His topic was "The Practical Side of MACT: Challenges and Complexities in Communicating the Issues." Randy's talk was informative and well received by the audience. His general message was that he would like to see a greater information exchange and cooperation between the regulatory agencies and industry.

In the panel discussion which followed the session, industry again expressed concern about having to respond to every question from the public no matter how outlandish and the agency expressed their rewarding experience in putting faith in the public. Most questions, however, were for Fred Chanania and concerned the upcoming NODA which sounds like a re-write of the currently proposed Hazardous Waste Combustion regulations. While he did provide some useful information in his responses, his general ending statement with each response was to be sure to read the NODA.

The luncheon speaker was USEPA Region VII Administrator, Dennis Grams, who had been stuck in an airport on Monday and could not make his originally scheduled Keynote address. Dennis had also spoken to the audience at the 1995 BIF conference. His talk then had been one of getting input into the regulatory process and forms had been provided. His luncheon talk this year was more of an historical review of the regulations. He seemed to relish the fact that he had forced the hazardous waste burning cement industry and the hazardous waste incinerators to sit down face to face and debate. (Accounts of which have been published elsewhere.) This writer would agree that was a good idea and reports of that encounter indicated that cement kilns were able to solidly make their case and expose the misinformation disseminated by hazardous waste incinerators. Dennis gave an ornery smile and said that he thought he was going to do that again. It was fun. The disturbing thing was, he believed that the agreement that he got out of both parties, not to disseminate misinformation, was actually adhered to by the hazardous waste incineration faction. Mr. Grams damaged his credibility when responding to a question from the audience concerning USEPA Administrator Carol Browner's desire to increase the cost of hazardous waste disposal for cement kilns when he responded that he knew Carol personally and she would never do something like that. It just wasn't her style. This writer provides the following quotation attributed to Carol Browner approximately one year ago, "What we want to do is level the playing field." Ms. Browner stated her view that cement kilns were taking waste for $104/ton while "state-of-the-art" hazardous waste incinerators were taking waste at $800/ton. Something she called "A pretty remarkable difference." She went on to say that, "If people have to pay the true cost of safe disposal [emphasis added] they will think about how to better minimize the amount of hazardous waste they are producing." All due respect to Dennis Grams for taking time to come to the conference and address attendees, but he was quite mistaken on this issue. Region VII cement kilns have stated that Mr. Grams is a reasonable regional administrator to work with. May his practical approach continue.

Following lunch, two concurrent sessions began. Session 2 was co-chaired by Suzanne Riney of Schreiber, Yonley & Associates and Jim Woodford of Gossman Consulting. This session was entitled, Trial Burn Planning and Experience. Session 4 was chaired by Stephen Bales of Ash Grove Cement and was entitled, Inorganic Emissions and Continuous Emission Monitoring. First, we'll discuss Session 2, which also turned into Session 3. For the record, many comments throughout the conference expressed dissatisfaction with the concurrent sessions approach as the BIF specialty conference has previously allowed attendees to experience all sessions.

The first presentation in Session 2 was by Chuck Kellett of Safety Kleen and he talked about "Trial Burning Experience - Planning, Preparation, and Pitfalls." Chuck's talk was an excellent presentation and very comprehensive. The next presentation was given by Tom Johns of Rhone Poulenc entitled, "Case Study, Trial Burn Process about a Sulfuric Acid Regeneration Plant." His talk was also excellent. He relayed the experience of the trial burn negotiation process and detailed the test parameters which were agreed to for the trial burn. An interesting difference from any cement kiln compliance test with which this writer is familiar was the placement of stack testers at 35, 100 & 200 feet to collect data for various parameters. Tom Johns was followed by Jim Woodford of Gossman Consulting, Inc. whose talk was entitled, "Follow-up Report on the Continental Cement Trial Burn Strategy" originally presented at the 1995 BIF conference. The Missouri Department of Natural Resources took a hard stance on the definition of an "official" observer which resulted in disallowing data-in-lieu-of a trial burn as clearly authorized by the regulation. Region VII had approved data-in-lieu-of for some portions of the trial burn. This resulted in a full blown compliance test when one was not necessary, with the associated risks of metals spiking, a much less environmentally friendly compliance test, if you will, and a test that was much more expensive due to the metals purchase necessary for the testing. One has to wonder where the "common sense initiative" was in the data-in-lieu-of denial or the concern for human health and the environment. The final talk of Session 2 was given by Val de la Fuente of USEPA in Washington, DC. His talk was on, "The Revisions to the Trial Burn Guidance Document Which Was Released in 1994." The new document is quite comprehensive and came out of meetings with all the regions which purportedly are doing things the same around the country. Val did not go into a lot of specifics but pointed out that the new document is consistent with "the Region IV NODs" and "the Region VI generic trial burn." The new document pulls together lots of information and is meant to coordinate the design of a trial burn with risk assessment data collection. At this point Session 2 ended with an exhibition break.

Session 3 began with a presentation from Craig Gotro and Mike Harrell of Medusa Cement in Wampum, PA. Their talk was about how they handle their CKD. The plant was originally designed to recycle all their dust, so when hazardous waste began to be burned rather than moth-balling the plant, something had to be done with their CKD since the plant had no storage. The CKD is mixed with cement and sold as an agricultural lime substitute used for non-agricultural uses. Under Pennsylvania law, this is a co-produced product which Medusa calls Earth Plus. They do have strict metals feed rate limits but do not have CKD to worry about. Craig & Mike's talk was followed by Nugent Myrick of SARP Industries, Inc. who talked about, "Management of Residual Industrial and Hazardous Waste Materials in France." He talked about making waste inert in France and setting standards such that landfilled waste did not have to be placed in special landfills. A question from the audience inquired how his process was any different than what Marine Shale had been trying to do. His response was that while he was not totally familiar with U.S. laws, for one major difference, his company had a real and existing market in France. Other than that, it was not terribly different. The final talk of the day was given by Irv Susel of Environomics. His talk was entitled, "The Benefits of Energy Recovery: Economic, Environmental and Social Benefits Recovering Energy from Waste in the Manufacture of Cement." His talk centered on data analysis performed for the Cement Kiln Recycling Coalition. It was interesting to hear him state emphatically that burning coal in cement kilns was more hazardous to your health than burning hazardous waste. A good deal of data was reviewed. Over all, the point of the presentation was that there is a greater risk to human health and the environment due to the MACT implemen-tation than if MACT were not enacted. There really was no challenge to anything that he presented so one has to wonder if EPA agrees, which as we all know is highly unlikely, or whether EPA just chose not to debate the issue at that time. This talk ended Session 3 for the day.

Session 4 ran concurrently with Sessions 2 & 3. Tony Griguoli of Environment USA gave the first talk of this session entitled, "A Potential Instrument Counterpart to Method 5 for Continuous Measurement." His talk was fairly straight-forward about real time continuous emission monitoring and particulate emissions. Based upon comments from Fred Chanania earlier in the day, it looks like particulate matter continuous emissions monitoring will soon be a reality. The next paper was presented by Craig Walquist of Cadence entitled, "Metal Feed Rates CKD vs. Input Streams." He talked about an "after burning" analysis that may be useful to use as a replacement for testing stack emissions every three years. He proposed the performance of a metals balance based upon known CKD wastage rate, known CKD metals concentrations and the known metal feed stream inputs. Questions from the audience suggest there are issues that still need to be resolved.

Dave Constans of Gossman Consulting, Inc. gave the next presentation entitled, "Observation and Comments on EPA/DOE Mercury CEMs Demonstration at Holnam, Inc.'s Holly Hill, South Carolina Facility." Dave had provided on-site monitoring for some of the USEPA contractor CEM work for which Holnam had volunteered their facility. Only one of the three mercury CEMs were indicated to be a possibility and even the best one was not very good. Dave gave a very thorough technical explanation of the CEMs and their problems in operation. Dave also pointed out that a mercury thermometer was dropped in the recovery trailer which may have compromised results for that day, if not for the rest of the project. Tony Moscati of Seneca Environ-mental Associates, Inc. presented the next paper entitled, "Characteristics and Trends in the Burning of Hazardous Waste in Cement Kilns." Tony presented data from USEPA 3007 requests and appeared to be trying to somehow condemn cement kilns for high metals input. Tony pointed out that the metals input rates were lower than the extreme conditions experienced in the COC testing. Most in the audience were uncertain what his point was. Pre-conference review of a similar report indicated that maybe Tony chose to duck insupportable issues in a pro-cement kiln forum. Michelle Lusk of CKRC and Brian Graf of ESSROC gave the final presentation before the break entitled, "Trends and Characteristics of Hazardous Waste Derived Fuel Burned for Energy Recovery in Cement Kilns: 1997 Update." Michelle had previously given a similar paper at the 1996 BIF conference and was providing an update this year. The industry is still burning approximately one-million tons annually and the metals concentrations continue to decrease. Brian then pointed out that cement demand in the Great Lakes region was much higher than what kilns could produce. The higher feed rates in the 1995 round of re-certification testing was necessary to meet the higher production demands. However, he also pointed out that on average, the feed rates of metals has decreased.

Dave Gossman of Gossman Consulting, Inc. gave the first presentation following the break entitled, "The Design of a Custom Database System for Storing and Accessing Point Source Emission Test Data and Associated Process Conditions." There is so much data out there now that there needs to be a way to collate the data and make it readily accessible. Dave's talk provided a way to do that and gave examples of how this might be implemented. Greg Mayes of TXI then talked about "XRF Screening" and the ease of use. Only two metals require additional analysis, mercury and beryllium, and EPA is giving indications of coming around to a realization that an analysis for these metals may not be necessary. Dave Gossman has been pushing XRF analysis for so long that he is associated with the technology by many of those within the regulatory agency. And speaking of Dave Gossman, he gave his second presentation of the session entitled, "A Model Waste Analysis Plan for a Commercial BIF." Dave is also readily identified with waste analysis plans. A very similar WAP model was provided to EPA, but essentially ignored, when they were finalizing their WAP guidance document. The WAP model is fairly straight forward and covers all the analytical bases. The final paper of Session 4 presented by Kay Ramsey of Auburn International, Inc. was entitled, "Air Emission Monitoring for Predictive Baghouse Maintenance and Environmental Compliance." Her talk concerned some type of broken bag detector that would allow several monitors to send signals to a PC plus watch for increased particle venting.

The second day began with Sessions 5 & 6 being run concurrently. Session 5 began with introductory remarks made by Eric Eddings of Reaction Engineering International with the first presentation being by Greg Rigo of Rigo & Rigo Associates. The title of Greg's presentation was, "Building of Emission Database and Estimating National Emissions, a Case Study." The case study was that of Greg's company's efforts to construct an accurate database of emission information from hazardous waste combustors (HWCs). This database, which parallels the effort of EPA in their emissions estimations used to support the proposed HWC rules, was prepared by going back to the raw data, reviewing it and the Summary Reports for errors, and ensuring that all significant errors are corrected. Greg's findings were that the Summary Reports from the tests used by EPA contained 15-30% significant errors. The error types were of units conversions, transcriptions, transposed numbers, and even such things as confusions over elemental names and their abbreviations. As an example of the significance of the errors Greg stated that emissions for all categories of HWC were reduced by 82% after the corrections were made. This had the effect of dropping the annual estimate of PCDD/PCDF emissions of the proposed HWC rule from 798 g/yr to 62 g/yr. In conclusion, Greg stated that Summary Report information should never be trusted until extensively reviewed for errors made in the conversion of the raw data to the final report information.

Bob Schreiber of Schreiber, Yonley & Associates presented the next talk entitled, "Comparison of HAPs and Hydrocarbon Emissions." Bob described an evaluation of emission data from the Rigo database, which contained 48 HAPs from 12 kilns, and tried to assess whether there is a correlation between hydrocarbon emissions from a cement kiln and emissions of products of incomplete combustion (PICs) HAPs. A multi-variant analysis was used to analyze the data to determine if a correlation exists. The emission data came from three wet process kilns and four preheater/ precalciner cement kilns. One of the wet process kiln's data was determined to be an outlier and was removed to make the final determination. The analysis deter-mined that there was no correlation between specific hydrocarbon emissions and the emission of (PICs) HAPs. Bob stated that organics in the raw material and process conditions were likely responsible in part for the inability of a correlation to be made between the two emission parameters.

The third presentation of this session was given by Steve Lanier of Energy & Environmental Research Corporation. Steve's talk was entitled, "Detailed Speciation Measurements at Cement Kilns Burning Hazardous Waste." This, in a more specific sense, was about an effort to characterize or identify the actual compounds that make up the more general emission category of hydrocarbon (HC) emissions. The testing was done on a long wet process cement kiln. Steve described the different and parallel testing procedures used as well as some of the sampling and analytical problems encountered such as a GC computer fire. The results demonstrated the difficulty in making this characterization as well as trying to demonstrate that there is consistency in the results. Steve described that the identification analysis compared to quantity reported by the HC CEM showed a mass closure of 83.7%, meaning that 16.3% remained unidentified except to say that it was believed to be light volatiles. Furthermore, when comparing one day to another, one-third of the identified compounds change. [This data is not consistent with findings at other trial burns.]

Eric Eddings of Reaction Engineering International gave the next presentation entitled, "Determination of Organic Emissions from Raw Materials and Waste Feedstocks in Cement Kilns." Analyzing the raw material for the content of organics can be viewed as a simple step. However, this presentation describes some fallacies in the assumption that all or most of the organics will be emitted. It also details other factors which should be taken into account. Eric's talk described a lab scale rotary reactor test which sought to evaluate the raw material normally used in cement kiln production for it's organic content and potential emissions. This test determined that just analyzing the raw material for total organic carbon (TOC) was insufficient to measure organic emissions because up to 90% of the organic material could become a solid non-emitted char rather than be emitted as gaseous hydrocarbons. In summary, Eric stated that to make an accurate assessment of organic emissions from raw material many process factors such as mixing, and temperature must be known. Further, a knowledge of the volatile content of the organics is also necessary before being able to predict emissions.

The final individual presentation of this session was scheduled for Eric Tiemeyer of Texas Industries. The title was, "Utilizing Vapor Vent-back/Vapor Balance Tech-nology to Eliminate VOC Emissions from Liquid Storage Tanks." His talk described the use of a well known technique in the fuel delivery and chemical industry of venting back to the delivery truck the organic vapors displaced during the unloading process. Included in the talk was an explanation of effects this has on reducing potential "other emissions" from any heal material left in the delivery truck. Also described were the controls of tank breathing losses of organic vapors. These controls included the design of tanks which meet ASME pressure regulations which means that vapor emissions are eliminated and contained within the vessel or tank. The overriding concept of this approach was to prevent, where possible, and contain the vapors that can't be prevented.

After the break, a brief discussion was held with all of the presenters forming a panel to field questions from the attendees. With the completion of this Q & A activity, session 5 was closed.

Session 6 was a session that was welcomed at the BIF conference in general, was long overdue, and will hopefully be perpetuated in some form in subsequent BIF conferences. The session was entitled, Boiler and Industrial Furnace Operation and was chaired by Continental Cement's Sam Waters, a premier operations guy in his own right. The first presentation of the session was by Stan Ehinger, the Holnam plant manger for the Clarksville, Missouri facility. His paper was entitled, "Issues of Operation During a Trial Burn at a Wet Process Kiln." Stan related the plant experience on their trial burn performed in early 1996 at about the same time as the Continental trial burn discussed in a previous session. Stan started his talk by pointing out that when talk begins about a compliance test, cement kiln operational people give out a collective groan. He talked about the trials and tribulations of his trial burn, but also pointed out that they completed it nonetheless. This burn was completed despite plugging a metals spiking line and having their load go semi-liquid subsequently burning up their clinker cooler grate. He appealed to EPA to shorten run time requirements so that testers can more safely perform compliance tests rather than running from 6:00 a.m. to 1:00 a.m. the next day trying to get in three runs. He also appealed to regulators to modify requirements, for why in the world would you put a maximum temperature on a cement kiln and encourage inefficiency by limiting production to what was established during the test? A cement plant's job is to make cement, not limit production.

The next talk was given by Tim Menke of Lone Star from the Greencastle, Indiana facility. His talk was entitled, "Reduction of Hydrocarbon Emissions can be Costly." Greencastle has spent the past three or four years fighting cement clinker quality because BIF has required them to alter their raw mix in order to get down below 20 ppm hydrocarbons. This limit was imposed upon cement kiln BIFs because of concern for incomplete combustion. Experience has demonstrated that they are not combustion related at all, but rather driven off as part of the raw material slurry drying process from naturally occurring kerogens. But in burning hazardous waste, they still had to comply even though there was no combustion relationship. In essence, they went from a two component mix to a five component mix and quality suffered in the process. At one point, they were importing raw materials from as far away as Missouri and Chicago. No calculations were presented to determine whether or not more pollution was created by all of this increased transportation as compared to the hydrocarbon reductions effected in the cement kiln stack gases. In the end, the plant added back in some of that hydrocarbon producing shale because it was simply an essential ingredient. At the moment, they are below 20 ppm hydrocarbons but there have been some minor feed rate restrictions as a result. Tim ended his talk by commenting that sometimes they wish they weren't burning hazardous waste so that they could emit whatever hydrocarbons they want and not have to worry about it.

Norris Johnson of the Lone Star Cape Girardeau, Missouri facility gave the next presentation entitled, "Advantages & Disadvantages of Burning Hazardous Waste in a Pre-calciner Kiln." Norris talked about how use of hazardous waste fuels had helped the Cape Girardeau kiln to burn more smoothly overall. It also helped to extend the life of their quarry operation. He went into numerous technical issues, which would be better explained by getting a copy of his paper than trying to summarize it here. One issue worth noting, though, had to do with metals emissions. Because of the way the preheater/ precalciner kiln is designed, CKD and metals are more or less "trapped" in the cement manufacturing system and, consequently, metals emissions from the Cape kiln are much lower than say a wet kiln such as Greencastle. He also expressed concern that the USEPA relied too much on metals emissions without considering the type of kiln emitting the emissions to develop their MACT standards.

The final speaker of Session 6 was Gary Pendergrass of Agribusiness Technologies, a company created solely to handle the Times Beach Missouri dioxin cleanup. His talk was entitled, "Overview of Times Beach Remediation Program." Those familiar with the Times Beach saga may recall that the Times Beach dioxin problems came from one used oil road sprayer who used dioxin contaminated oil to spray as a road dust suppressant. The project involved numerous sites around the area but Times Beach got the most attention. Gary's parent company inherited the problems through acquisition. Final cleanup of Times Beach is scheduled for this year and it will become a state park.

The luncheon speaker that had been scheduled was Roger Pryor of The Coalition for the Environment. Roger had called and cancelled at the last minute, so Conference Technical Chairperson, Bob Schreiber, had done some last minute scrambling to save the day. He got Roger's lawyer, Lou Green. Lou kept telling us that risk assessment is not a science and that we should stop telling the public that things are safe. It was interesting that he could tell us risk assessment was not a science, but then beg off any technical questions by saying he wasn't technical.

Session 7 commenced with an opening comment from the session chair Mario Mangino of U.S. EPA, Region V. The first presentation was made by Jeff Shirai of Delta Toxicology and was entitled, "Chemical Characteristics of Cement Kiln Dust (CKD) and their Effect on Dioxin-Related Health Risks." Key points in Jeff's talk were that CKD varies little in pH and chemical composition. Also, from reviewing test data it was evident that dioxins do not readily leach from CKD under TCLP procedures. In assessing the health risks, they determined that the maximum risk calculated from the dioxins that leached was 3.41 x 10-7 for the six scenarios evaluated which included the subsistence farmer. In his summary, Jeff stated that while some variability was found in the risk numbers calculated, the variations were due to analytical limitations, i.e. there were many non-detects which for the purpose of the risk were not treated as zero but as the value of the detection limit. This not only introduced variability but also artificially high risk numbers.

The next presentation was by David Weeks of U.S. EPA, Region VI. The title of his talk was, "Region VI Protocols for Screening Level Human Health and Ecological Risk" David presented a very direct explanation of the draft protocols developed by Region VI. Key points that David made were that this will probably be the protocols that headquarters EPA will adopt. This health risk assessment (HRA) is a screening level approach rather than a specific HRA and it is multi-pathway. All HWC type units will be required to perform this HRA even if they choose to do a more specific and detailed HRA. This HRA will be in essence a standard by which all facilities will be compared. One final important point was that fugitive emissions are included in the HRA.

The next presentation of this session was given by Jeff Yurk of U.S. EPA, Region VI, and was the second part of the talk begun by David Weeks in the previous presentation. Jeff spoke about what the draft protocol actually contained in a physical sense, and that is the guidance information and a workbook. He also discussed some of the ecological risk aspects of the guidance in the protocols such as the use of a food web in its entire scope. He gave examples of how optional choices can be used to set up exposure pathways. With the options, they feel this allows for more realistic protocol although it may cause the assessment to go beyond just health effects and bring in economic or social effects as well. Jeff made it clear that as a risk assessor he felt this was a very good protocol, and he reiterated that this HRA was a screening level process and may not have detail enough for all HRAs that may be required.

After the break, the next talk was given by Mario Mangino of U.S. EPA, Region V. His presentation was entitled, "Public Participation is an Important Component in Risk Communication for Hazardous Waste Combustion Facilities." Mario's key points were about knowing your audience, i.e. the different stakeholders, and about being able to address those stakeholder's unmet expectations. He further described EPA's major steps or outline of the process as being Early Notice, What The Facility Must Do; More Public Notice, and What The Agency Must Do. Mario also referenced the public participation guidance manual issued from EPA in September 1996. He used as a case study some public participation issues that came up for the Rhone Poulenc facility near Chicago.

The final presentation of this session and of the conference was given by Gary Liberson of Environmental Risk Sciences and was entitled, "Risk Issues in the Development of the HWC MACT Proposed Rule." Gary presented work that was performed on behalf of CKRC and demonstrated that EPA used risk assessment methodologies that were overly conservative.

Closing Comment: Over all, the conference seemed to be well received by attendees. Presentations were informative and helpful for the most part. Many positive comments were made. The one consistently negative comment concerned the concurrent session approach used at this year's conference. Again, this year's data presentations were ones of experience and confidence. The industry has been through the regulatory mill, has tested their kilns extensively and is advancing the notion of fair regulations based upon a strong knowledge base. The agency is giving signs of finally starting to listen, so it will be interesting to see where things go from here