July 2, 2002

Thank you for your letter dated April 4, 2002, regarding exposure issues at the ICSTF. Indiana Department of Environmental Management (IDEM) staff have been working with the U.S. Environmental Protection Agency (U.S. EPA) to respond to your questions.

Paragraph 1: Workers at ICSTF and the public are impacted by polychlorinated biphenyls (PCBs) released to the air.

Response: The U.S. EPA did consider the possibility of worker exposure to airborne polychlorinated biphenyls (PCBs). To determine the risk of exposure inside the plant building, the U.S. EPA conducted air sampling at the ICSTF July 4, 2001, and October 24, 2001. As stated in our March 18, 2002, letter, this sampling was highly biased, and conducted under worst case scenario conditions. The sample results did not show significant risk to workers inside the facility. However, the U.S. EPA decided to conduct further air monitoring to ensure workers and the public are not impacted by air emissions from the ICS facility. The U.S. EPA conducted personal air monitoring and perimeter air monitoring at ICSTF from April 7, 2002, to April 19, 2002. Five high-volume air samplers were used to collect samples and a plant operator was monitored using personal air monitoring equipment. U.S. EPA Methods TO 4 and TO 10 were used for sample collection and analysis. Two monitors were placed adjacent to each other (as a duplicate monitor) to the south near the housing units, one monitor was placed near the spring receiving sump building, a monitor was placed to the north and a background monitor was located in Ellettsville. During the monitoring timeframe, a large storm event produced overflow of the storage tanks at the treatment plant. Details of the air monitoring, including the final results, are located in the information repository at the Monroe County Public Library under Tetra Tech's Field Sampling and Analysis Plan for Illinois Central Spring Emergency Response Site, dated April 3, 2002, and Tetra Tech's Field Sampling and Data Validation Report for Illinois Central Spring Emergency Response Site, dated May 31, 2002. Attached is Table 1 from the Field Sampling and Data Validation Report that includes the air monitoring results.

Dr. J. Milton Clark of the U.S. EPA has evaluated the results from the air monitoring and completed a risk analysis for the nearby residents of the ICSTF. As described in Dr. Clark's June 6, 2002 memorandum, which can be found in the information repository, the cancer and non cancer risks are well within U.S. EPA risk levels. Using a reasonable maximum daily exposure, the south monitors near the housing units show an excess cancer risk of 2 in 1,000,000. This value is well within U.S. EPA's risk range of 1 in 10,000 to 1 in 1,000,000 excess cancer risk. The non cancer risk, using the hazard index of 1.0, is 0.19. As can be seen in the report, no samples from the personal monitoring exceeded 1.0 ug/m3, the National Institute for Occupational Safety and Health (NIOSH) standard for an 8-hour worker exposure. The standard used in industry, and the standard that is enforceable by the Occupational Safety and Health Administration (OSHA), is 1,000 ug/m3 for an 8-hour exposure.

General Comment 2: IDEM is not operating the facility properly.

Response: As of May 20, 2002, IDEM has spent $160,000.00 to operate and maintain ICSTF, as opposed to the millions of dollars you claim. We are operating the facility as designed, and continue to be somewhat surprised by your lack of understanding of how the water treatment operable unit for the Lemon Lane Landfill is being implemented as a pilot plant. As described in previous correspondence, the ICSTF was built under the U.S. EPA's removal authority to allow the governmental parties to have an operational water treatment plant during the Lemon Lane Landfill source removal. Also, as described in previous correspondence, effluent limits will be determined when the final remedy for water treatment is determined. A Proposed Plan with public comment will be issued in the future. After evaluating the proposed site remedies using the nine criteria described in the National Contingency Plan, a Record of Decision Amendment will be issued by the U.S. EPA. Please see IDEM's letter to you dated March 27, 2002, for a discussion of the facility design, operation, reporting, discharge limitations, and overflow events.

IDEM staff have never tried to "spin" the issue of overflow events. The monthly operation reports clearly state the amount of water that has been overflowed from the tanks, as well as how much was treated, stored, and bypassed. This information, as well as other information regarding the future of the ICSTF, has been given to you numerous times, however, you continue to misrepresent our efforts and the operation of this facility.

Specific Comment 1: Henry's Law Conceptual Errors.

Response: Mixture data was used in the calculations. ICS contains a mixture of many PCB congeners, not pure congener or a mixture of a few congeners. This same situation (complex mixtures) applies to all real world (non laboratory) PCB contaminated sites. Furthermore, most of the available physical data vapor pressure, molecular weight, etc. are the congener fraction weighted values for the common mixtures (Aroclors). Most of the available physical data for individual congeners are extrapolations and other estimates, not measured values. The use of parameters for a single congener to estimate the properties of a mixture will produce unreliable results.

Specific Comment 2: Worker's right-to-know requirements.

Response: All persons who work at the facility are required to read and sign the site Health and Safety Plan. Workers right-to-know information, which includes Material Safety Data Sheets (MSDS) is bound in a bright yellow and black striped binder, and is placed in a bright yellow wall bracket labeled "Right-To-Know Information." This wall bracket is mounted in a direct line of sight with the office door. Directions to the hospital and emergency numbers are posted on the bulletin board.

To ensure the safety of the plant operators, a personal air monitor was worn by a facility operator for 11 days. Every measured value was under the NIOSH PCB value of 1ug/m3, which is 1000 times lower than the OSHA value. Dr. Clark has reviewed the personnel air monitoring data and concluded that visitors, including women, would have no significant cancer or non cancer health risk.

All employers are required to implement medical monitoring for employees that may be exposed to hazardous materials at least 30 days per year. All persons who work at ICSTF are on a yearly monitoring schedule.

Specific Comment 3: The sediment is also an air contamination source.

Recent air monitoring data does not indicate that wet sediment is a source of PCBs. Personal monitoring during the sludge pressing operation showed that PCBs were not being volatilized. However, we will continue to evaluate the treatment process to determine if additional controls for air emissions are required.

This site is not subject to Resource Conservation and Recovery Act (RCRA) storage requirements. PCB waste is regulated by the Toxic Substances Control Act (TSCA). TSCA regulation 40 CFR 761.65(a)(1) states that the waste must be disposed of within one year of generation. The ICSTF sludge is disposed of approximately every six months.

Specific Comment 4: PCB emissions are a significant problem.

PCB emissions from the Bloomington sites are not producing significant cancer or non cancer health risk. Your calculations using old air data from 1993 and earlier do not reflect current conditions. However, your own calculations using these numbers indicate the risk is well within U.S. EPA guidelines. Your assumptions regarding air exposure and health risks do not take into consideration the numerous source control remedies that have occurred since that time. The remediation of the ABB Plant site, Fell Iron & Metal, the west side of Clear Creek, Winston Thomas, including the 17 acre tertiary lagoon, the Interim Storage Facility, Neal's Landfill, Lemon Lane Landfill and Bennett's Dump has removed thousands of tons of PCB contaminated material from Bloomington.

Regarding spring monitoring, PCB concentrations in the springs at Neal's Landfill have lowered since the source control was completed, and monitoring at ICS shows that PCB concentrations have returned to pre source control levels. Your statement that the new cap at Lemon Lane is more permeable than the cap installed during the interim measures is somewhat puzzling. Not only was over 80,000 tons of PCB contaminated material removed, but the new cap contains two feet of compacted clay, a flexible membrane liner similar to the plastic liner installed during the interim measures and two feet of fill with no venting for methane gas. This, along with the air monitoring data completed at the end of the Lemon Lane source control cleanup, does not substantiate your assumptions.

Specific Comment 5: The problem extends beyond Bloomington.

Response: You seem to infer from your comment that fish advisories for streams not connected directly to the Bloomington sites are caused by the volatilization of PCBs from the Bloomington area. Based upon air monitoring data at the ICS plant and air monitoring data at the end of the remediation of the ABB Plant site, Fell Iron & Metal, the west side of Clear Creek, Winston Thomas, the Interim Storage Facility, Neal's Landfill, Lemon Lane Landfill and Bennett's Dump, your claim that Bloomington is being exposed to harmful levels of PCBs from the air is incorrect. The plant is being operated properly and the operating reports are accurate and complete.

Specific Comment 6: The Sampling and Analysis Plan

Response a): All data that relates to the facility is reported in the Monthly Reports, which are placed in the Monroe County Public Library, as well as posted on the internet at http://copa.org.

Response b): The Operation and Maintenance (O&M) Plan states that the autosampler takes two 700 milliliter (mL) aliquots. That is a typographical error. The sampler takes two 900-mL aliquots. The O&M Plan will be corrected to reflect the accurate volume. The two 900 mL aliquots comprise a one-hour composite sample. To determine if the autosampler protocol we are following has any impact on sample results, I requested that the operator take some comparison samples. The operator collected two additional samples almost simultaneously while the automated sampler took aliquots for a composite sample. Comparison sample A was collected with a clean dipper from the end of the 24" inlet pipe before the water fell into the Spring Receiving Sump (SRS). Comparison sample B was collected with a clean dipper by accessing the manhole outside the SRS building. Both samples A & B were capped and refrigerated immediately. Comparison sample C is composite sample bottle #3 which remained inside the refrigerated automated sampler un-capped until the operator serviced the sampler (approximately 11 hours). Samples A & B were collected within 5 min. of the automated sample. The results are as follows:

Comparison Sample A: 1.4 parts per billion (ppb)
Comparison Sample B: 1.8 ppb
Comparison Sample C: 1.7 ppb

As you can see, the sample results compare well, and thus, the sample results are not affected by the use of the autosampler.

Response c): Samples are chosen for analysis based on the spring flow generated by the storm. We submit one sample for the beginning of a storm event, the sample that corresponds with the peak flow of the spring, and the first sample after a storm that corresponds with flows of less than 500 gallons per minute (gpm). Obviously, it is not possible to separate the 900 mL aliquots once they are placed in the sample container.

Response d): Dissolved oxygen, pH, specific conductance, and temperature measurements are taken on both influent and effluent samples.

Response e): Granular Activated Carbon samples are taken quarterly to assess the need for carbon change-out. Sludge sampling is currently done only for disposal purposes. However, this information is used to determine if any changes in operation are warranted. Additional sampling for optimization purposes may be done at a future date.

Response f): Parameters for sludge analysis are determined by the disposal facility. "Standard Methods" refers to "Standard Methods for the Examination of Water and Wastewater," 17th ed. 1989, prepared jointly by American Public Heath Association, American Waterworks Association and the Water Pollution Control Federation, as well as standard methods for analysis listed in 40 CFR 136.3, Appendix A. Water samples are analyzed for PCBs using EPA Method 608, which is a method required by the National Pollutant Discharge Elimination System (NPDES). Please see IDEM's letter of March 27, 2002, for a discussion of the facility's NPDES requirements. Please see the U.S. EPA's letter of April 22, 2002, for a discussion of using the Aroclor method of analysis for PCBs, rather than the congener method. I have attached a table listing our testing methods and parameters.

Response g): IDEM has no information to suggest that the water samples sent for analysis are decanted and the sediment discarded or allowed to remain in the sample bottle. We would appreciate receiving any information you may have that our laboratory routinely decants samples.

Your continuing criticism of our efforts is quite disheartening, considering we have openly communicated our intentions, and provided all of the information you have requested. We will continue to provide you with information, however, it would be beneficial to everyone if you would carefully consider the responses to the questions you have previously sent, before submitting additional questions. If you have any further questions, you may contact me at (317) 233-2823.