1. 1 Waste Water Discussion 28 January 2013 confidential

2. Agenda  Purpose:  Discuss and review wastewater project with COG, PSE, DOE, & Nalco.  Process:  Review where we were and the agreed upon process  Discuss the findings of the study period: -Analytical -Mechanical -Operational  Discuss where we are now  Pay Off:  Develop & Discuss how we move forward from here 2

3. Where we were…  October 28, 2011  Letter from City of Goldendale to DOE  “the City has had problems complying with TSS effluent limits;”  “City has modified operations to mitigate the high suspended solids on the WWTF’s effluent TSS Concentration.”  “PSE’s discharge of high suspended solids concentrations on its wastewater has caused detrimental effects on the WWTF in terms of low effluent pH violations and impairment of the City’s ability to meet Ecology’s reliability and redundancy criteria for WWTF and operations.” 3

4. Where we were…  October 28, 2011  Letter from City of Goldendale to DOE  “The City has determined that the solids in the station discharge are primarily inert.”  “The solids in the Station discharge do not easily stay in suspension in the aeration basin at the WWTF and settle to the bottom of the basin without extra mixing energy.”  “Based on information from the City Staff, the Station inert solids appear to also promote the settling of the biological solids (microbial mass) that performs the wastewater treatment in the aeration basin. The solids must be kept in suspension in order to provide treatment.” 4

5. Where we were…  October 28, 2011  Letter from City of Goldendale to DOE  “When the station discharges, three blowers are required to operate to keep both the inert and biological solids in the aeration basin in suspension.”  “At current flows and loadings, the WWTF is required to run three 60- hp blowers instead of a single blower.”  “Typically the WWTF aeration basin would operate with a dissolved oxygen level of 2.0 mg/l to maintain adequate treatment. Operating three blowers raises the dissolved oxygen level in the aeration basin excessively high to 6.0 – 8.0 mg/l. ” 5

6. Where we were…  October 28, 2011  Letter from City of Goldendale to DOE  “Typically the WWTF aeration basin would operate with a dissolved oxygen level of 2.0 mg/l to maintain adequate treatment. Operating three blowers raises the dissolved oxygen level in the aeration basin excessively high to 6.0 – 8.0 mg/l. ”  “The higher oxygen level has a negative effect in that it prevents denitrification from occurring in the basin. Denitrification is a part of the process whereby alkalinity is recovered and thus minimizes pH drop at the WWTF.”  “In recent years, the City has violated the permit 19 times for low effluent pH.” 6

7. Where we were…  October 28, 2011  Letter from City of Goldendale to DOE  “The continued discharge of high wastewater TSS from the station will also require the following capital improvements and future operation and maintenance costs for treatment: -“A new 60-horsepower blower…to meet DOE reliability and redundancy standards.” -“A larger emergency power generator…to meet DOE reliability and redundancy standards.” -“A caustic feed system is required …to prevent low pH violations of the permit. -“the amount of caustic required…is greater because additional blowers needed to mix station solids prevent denitrification and the associated alkalinity recovery. 7

8. Where we were…  December 14, 2011  Meeting at PSE with David Van Cleve of Grey & Osbourne  MLSS Dropping from September through December  Ammonia Concentration Up  Solids building on North side of aeration pond.  Completely Stopped Wasting  Started adding Molasses as a nutrient source for biologics  Nalco gained agreement with COG to sample aeration pond  Nalco grabbed sample and executed Wastewater Biomass Analysis -Microbiology showed that system had an Old Sludge Age -Typical corrective action would be to increase wasting rate 8

9. Where we were…  March 15, 2012  Meeting at COG, PSE, Grey & Osbourne, & Nalco  Primary Discussion Points: -High Ammonia Levels in Effluent -TSS Levels moderate to High in Effluent -pH low -Denitrification in clarifiers -Floc like substance in effluent -Foam accumulation in aeration basin extending to the clarifiers -Slow building sludge accumulation in basin -Fecal coliforms – low to high  Nalco was asked to deploy resources 9

10. Where we were…  March 27, 2012  Nalco grabbed sample and executed Wastewater Biomass Analysis -Microbiology showed that system had an Old Sludge Age -Typical corrective action would be to increase wasting rate 10

11. Where we were…  May 24 & 25, 2012  Nalco Senior Consultants John Sparapany & Mike Olson along with John Deines execute kick off meeting with COG & PSE  PSE Attended walkthrough at COG  COG Attended walkthrough at PSE  After discovery process, Nalco proposed the following plan: 11

12. Where we were…May 25, 2012  Purpose:  Discuss path forward for evaluating, defining, and troubleshooting system stress at City Waste Water Plant  Process:  Review Scope of Work for Evaluation Period -Sample Points -Analysis -Frequency -Follow Up  Define our next steps -Gain Agreement on Path Forward  Pay Off:  Develop a complete understanding of the proposed path forward and the timelines associated with it 12

13. PSE Power Plant 13 A: Supply Water Analysis: RC Every 2 Weeks B: Service Water Analysis: RC Every 2 Weeks C: Neut. Tank Analysis: RC + Dep + TSS Every 2 Weeks D: Pre-Chiller Analysis: RC + Dep Every 2 Weeks E: Discharge Analysis: RC + Dep + TES Every 2 Weeks

14. City Waste Water System 14 A: Supply Water Analysis: RC + Dep + TES Every 2 Weeks B: Aeration Basin Analysis: D/SOUR Every 2 Weeks X D: Aeration Basin Analysis: Dep Every 2 Weeks

15. Data Collection & Trending…  Current Plant Data + New Data to be trended using Excell or V100 Software  GOAL: Investigate & Link – Cause & Effect 15 confidential

16. Project Goals…  Define “footprint” of water as it flows through PSE  Sample COG Influent Water and Aeration Basin  Samples at Effluent of PSE & Influent at COG to be pulled using composite sample  Samples to be executed every two weeks until meaningful trend is obtained  After samples collected and reviewed, conduct another meeting discussing findings and results.

17. Explanation of Analytical Tests…  Water Analysis  RC – Routine Metals, Anions, & Wet Chemistry  21 Total & Soluble (0.45 Micron Filter)  Metals by ICP  Anions by IC -Chloride -Nitrate -Sulfate -Bromide  Conductivity  P/M/O Alkalinity & pH  TSS 17

18. Explanation of Analytical Tests…  Solids Analysis  Deposit –  This analysis reports the concentration of elements in weight percent as oxide for elements from fluorine to uranium present in concentrations > 0.5%. In addition x-ray diffraction is used to determine crystalline compounds present. When possible, the diffraction results will be semiquantitative. Three gravimetric tests are included: loss at 925 C, % CO2, and % dichloromethane extractables. 18

19. PSE Analytical Results…  Silica is predominant in Supply Water (Sample A.)  Silica is predominant solids component in the Neutralization Tank Effluent (Sample C: Water & Solids.)  Silica is predominant in Discharge as well (Sample E.) 19

20. COG Analytical Results… 20  Silica is predominant in Supply Water to COG  Silica is on average 47% of total inorganic solids  Silica is dominant in the Supply Water to the City as a whole. Due to this, PSE is not the only contributor of concentrated silica to the COG WWTF.

21. Explanation of results… 21  Inert solids loading for this plant is fairly normal.  Only way that these solids can impact the DO levels is if the solids are oxidizable.  The silica in PSE’s effluent is already oxidized and converted to SiO2 in the Neutralization Tank. This is what makes it insoluble. As a result, it will not consume much oxygen.  Data supports that PSE is a contributor of insoluble compounds to the COG; however, there are other significant contributors to inorganics in the COG system.

22. COG – Excellent Work yields great results… 22  Diffusers were removed and repaired in 2012  50% of the nozzles were broken  “Diffuser repair was biggest difference maker in 2012.” – R. Cooke  3 rd Blower Issue resolved. No longer needed.  Dissolved Oxygen Levels much better.  Utility savings over $1000.00 per month from Oct 2011 through Oct 2012  COG Operations reached out to City of West Richland  Effort to better understand microbiology of Aeration System  Initial findings that system had an “Antique Sludge Age.”  System Wasting Rate needed to be increased  Average Wasting Rate has been increased from 2000 GPD to 4400 GPD  Old biomass gone. System microbiology much more diverse and functional  Due to these two items – pH control much better

23. COG – Excellent Work yields great results… 23  Determined that they have a “Tremendous INI Issue.”  INI = Inflow and Infiltration  Rain and Run Off Events double the mass flow to the system and make treatment very difficult.  Loads system up hydraulically and unknown system solids  Makes Operations and Treatment of WWT very difficult  Determined FOG is an issue that needs to be resolved  FOG – Fats, Oils, & Grease  Makes settling harder and raises TSS

24. 24 Discussion…

25. 25 Discussion…

26. 26 Discussion…

27. 27 Discussion…

28. COG Data – Ammonia vs Dissolved O2 28

29. COG Data – DO, pH, & NH3 29

30. COG Data – DO, pH, & NH3 30

31. 31 Discussion…