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consent decree also required KPC to develop and implement a program to monitor the ambient 

 concentrations of sulfur dioxide and particulate matter 



The follow-up modeling study was conducted during the summer of 1995 utilizing facility- 

 specific emissions data (as opposed to generic industry emissions factors) as well as a more 

 refined dispersion model and health risk assessment model 



The follow-up modeling study indicated that KPC's emissions were in compliance for certain 

 standards but yielded inconclusive results with respect to sultur dioxide and particulate matter. 

 With respect to these pollutants, the follow-up modeling indicated that the facility had the 

 potential to exceed the NAAQS under certain worst case conditions Under most 

 circumstances, modeling is believed to be overly conservative in estimating ambient air 

 emissions. One way to test this hypothesis is through ambient monitoring. 



KPC commenced its ambient monitoring program in February 1 996 at two locations near the 

 pulp mill facility. The monitors are programmed to assess ambient concentrations of 

 particulate matter and sulfijr dioxide Thus far, the monitors have recorded one exceedance of 

 the three hour standard for sulfijr dioxide in June 1 996 This exceedance occured in June 

 19%. It resulted fi^om an operational upset at the pulp mill which released approximately 

 twenty-five pounds of sulfiir dioxide into the ambient environment KPC recognizes that this 

 operational upset could recur and intends to install a scrubber to capture sulfijr dioxide 

 emissions at the source 



The consent decree also required KPC to undertake a comprehensive modeling and health risk 

 assessment of chloroform emissions. KPC tested emission sources at its facility to detemiine 

 the concentration of chloroform emitted under typical operating scenarios This data was then 

 incorporated into a computer model to determine potential ambient concentrations of 

 chloroform resulting fi-om KPC's processes. From this, KPC conducted a refined health risk 

 assessment utilizing a range of probable receptor variables After extensive review by ADEC 

 and air toxicology consultants retained by KPC, the State of Alaska determined that the risk of 

 increased cancer posed by KPC's chloroform emissions was acceptable and within the State's 

 risk level of one in one hundred thousand (1/100,000) Moreover, anticipated process changes 

 to KPC's bleach plant (ECF conversion, discussed above under Recent Enforcement) are 

 expected to significantly reduce chloroform emissions (up to 40%) thereby fijrther lowering the 

 potential risk to human health posed by chloroform emissions. 



The existing consent decree incorporates by reference numerous provisions fi^om the expired 

 air permit. In eflFect, it is the fiinctional and legal equivalent of an air operating permit and has 

 been treated by KPC and ADEC as such 



Currently, ADEC is in the process of finalizing the most recent draft air operating permit. The 

 permit is expected to be issued in the summer of 1996 



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