DAQ Progress Report on Hydrogen Sulfide Study at Paper Mills

1. DAQ Progress Report on Hydrogen Sulfide Study at Paper Mills • Presentation Summary - Rule requirements for monitoring study - Conduct and reporting of study - DAQ review for approval - Study purpose: Replace prior uncertain data with quality- assured data from actual monitoring

2. Rule Requirements for Emission Study • April 2005 effective date reducing hydrogen sulfide (H2S) Acceptable Ambient Level (AAL) from 2.1 to 0.12 mg/m3 (1,500 ppb to 83 ppb) • Included exemption of wastewater treatment systems (WWTS) at paper mills • Required paper industry to conduct WWTS study estimating H2S & total reduced sulfur (TRS) compounds emissions • Study report to DAQ in November 2005 • DAQ report to EMC in January 2006

3. Rule Requirements For Dispersion Modeling • Use estimates from study in dispersion modeling • If dispersion modeling shows predicted H2S level below AAL, no further action required. • Submit favorable modeling data to DAQ by July 1, 2006, with DAQ reporting results to EMC by September 1, 2006. • If modeling shows H2S AAL exceeded, industry submit ambient air monitoring plan to assess actual H2S levels typical of mill operations by September 30, 2006 for DAQ approval.

4. Scope of Phase I Study • Minimum scope: Estimate air emissions at typical paper mills for H2S and TRS • Implemented scope: • Measure air emissions at 3 paper mills for H2S, TRS, and methane • Measure water composition and flow • Combine air and water data for mass balance • Develop model to predict air emissions • Synthesize emissions for one mill

5. Air Emission Monitoring • Identified method from similar 1989 mill study • Method consists of measuring downwind plume: - At 10+ horizontal locations • At 4 vertical elevations • Using mobile sampling cart and tethered balloon • 6 and 30 ft high weather stations • Considered sophisticated and advanced approach

6. Ambient Air Sampling Equipment

8. Phase I Study Schedule

9. DAQ Involvement in Study • Started in May 2004 • Team of DAQ chemists, engineers, and dispersion modelers • With 2 NCSU professors • Hired expert analyst with experience in same method with same sulfur compounds • Collaborated with US EPA chemists and engineers

10. DAQ Review for Approval • Sampling and math procedures approved • However, given key QA criterion not routinely met, found most analytical data unacceptable • EPA found analytical data “questionable, … hopes more suitable study conducted in future” • Feasible Phase II study data collected and modeled in time for July 2006 milestone

11. Unacceptable Analytical QA Results

12. Phase II Study Plan • Industry submitted Phase II Plan in February 2006 • DAQ approved plan with one minor change • Re-measure emissions at Plymouth & Roanoke Rapids - Synthesize emissions for other 2 mills • Key analytical QA data good in Pre-Phase II work • Perform dispersion modeling for all 4 mills to predict hydrogen sulfide levels at property lines • Plan to submit emission study and dispersion modeling results by July 2006

13. Acceptable Analytical Results

14. Phase II Study Schedule