Slide 1: Eagle Valley Generating Station corrective measures assessment public meeting
1 Eagle Valley Generating Station corrective measures assessment public meeting May 8, 2024
Slide 2: Agenda
Agenda Topic AESI Overview Presenter Brandi Davis-Handy, AESI President, AES Indiana AESI Eagle Valley Mark Holbrook, AESI Plant Manager Environmental Pilar Cuadra, AESI Regulations Environmental Manager Eagle Valley CMA Steve Putrich, Haley & Aldrich Report Professional Engineer Summary and Next Pi
Slide 3: AES Indiana overview
AES Indiana overview Brandi Davis-Handy President, AES Indiana 3
Slide 4: AES Indiana generation and service territory
Lakefield PPA (MN) – 200 MW Hardy Hills – 195 MW 528 Hoosier Wind – 100 MW square miles Harding Street Generation – 1,079 MW 521,00 customers REP Projects – 96 MW 3,956 Eagle Valley Gas – 671 MW MW of Generation Petersburg Generation – 1,072 MW Petersburg Energy Center Solar – 250 MW solar + 45 MW B
Slide 5: Accelerating the future of energy, together
Accelerating the future of energy, together Customer Economic and Centric Community Create exceptional Development customer-focused Community investments experiences improving quality of life Sustainability Reliability Transforming to Modernizing our grid cleaner, greener technologies 5 All Together
Slide 6: Improving lives, by delivering greener, smarter energy solutions
Improving lives, by delivering greener, smarter energy solutions the world needs Our Values Safety Highest All first standards together TLP: Restricted
Slide 7: AESI Eagle Valley overview
AESI Eagle Valley overview Mark Holbrook Plant manager 7
Slide 8: Eagle Valley Generating Station
Eagle Valley Generating Station In Service from 1947 to 2016 In Service in 2018 395 MW 671 MW 30% Efficiency 67% Efficiency 8
Slide 9: Eagle Valley Generating Station
Eagle Valley Generating Station → Located in Martinsville, IN on 650 acres → Stopped coal use and coal combustion residuals (CCR) production in April 2016 → CCGT commercial operation began in April 2018 → Significant reductions in air emissions 9
Slide 10: Environmental regulations
Environmental regulations Pilar Cuadra Environmental manager 10
Slide 11: What are Coal Combustion Residuals?
What are Coal Combustion Residuals? → Coal Combustion Residuals (CCR) are byproducts generated from the combustion of coal from coal-fired power plants → CCR contains trace metal elements, generally called CCR constituents 11
Slide 12: 2015 CCR Federal Rule: general requirements
2015 CCR Federal Rule Rule overview – General requirements Establish groundwater Initiate and complete closure Publish compliance data and monitoring systems to of CCR units within a specific information to a public determine if there are impacts timeframe. website. to the groundwater above groundwa
Slide 13: 2015 CCR Federal Rule: implementation
2015 CCR Federal Rule Rule overview – Implementation Detection Assessment Corrective Measures → 8 Initial Events → Twice per Year → Assessment → Twice per Year → Nature & Extent → Selection of Remedy → Implementation 13
Slide 14: Eagle Valley CMA report
Eagle Valley CMA report Steve Putrich Professional Engineer Haley and Aldrich 14
Slide 15: Technical Agenda
Technical Agenda CCR Groundwater Program & Groundwater 1 Monitoring Results Corrective Measures Assessment (CMA): 2 Background & Process 3 CMA Analysis and Results 4 Conclusion and Next Steps (H&A/AESI) 15
Slide 16: CCR Groundwater Program & Groundwater Monitoring Results
CCR Groundwater Program & Groundwater Monitoring Results
Slide 17: EVGS Site Features
EVGS Site Features FORMER POND E • The EVGS Ash Pond System POND C Natural Gas including Ponds A, B and C & Former Ponds D and E has a total acreage of FORMER POND D Plant POND B POND A approximately 70 acres. • Ponds A, B, C subject to federal rule, Former Ponds D&E not subject to federal rule but
Slide 18: Overview of the CCR Groundwater Monitoring Program
Overview of the CCR Groundwater Monitoring Program Groundwater Monitoring Detection Monitoring Assessment Monitoring 18
Slide 19: CCR Compliance Groundwater Monitoring Wells
CCR Compliance Groundwater FORMER Monitoring Wells POND E POND C FORMER Natural Gas Plant • AESI has been monitoring groundwater quality at POND B POND D EVGS in compliance with the CCR Rule since 2016. POND A • CCR monitoring wells include a total of 12 well locations installed immediately upgradie
Slide 20: CCR Rule Groundwater Monitoring Program & CMA Development
CCR Rule Groundwater Monitoring Program & CMA Development (40 CFR 257) Exceedance of GWPS Groundwater Triggers Nature & Extent (N&E) Investigations and Corrective Monitoring Measures Assessment Detection Monitoring Nature & Extent (N&E) Investigations Assessment Monitoring 20
Slide 21: Nature & Extent Groundwater Monitoring Wells
Nature & Extent (N&E) FORMER Groundwater Monitoring Wells POND E POND C FORMER POND D Natural Gas Plant • A total of 17 Nature & Extent (N&E) wells were installed south and west of the Ash POND B POND A Pond System. • The N&E wells are used to determine the nature (i.e., to measure the CCR constitue
Slide 22: Generalized Groundwater Flow
Generalized Groundwater Flow FORMER POND E POND C Natural Gas • Groundwater near the Ash Pond System Plant naturally flows west toward the White River. FORMER POND D POND B POND A • However, three production wells located east of the Ash Pond System influence groundwater flow across the Site, creati
Slide 23: Findings from N&E Investigation
Findings from N&E Investigation FORMER POND E • The horizontal extent of groundwater impacts POND C covers approx. 360 acres which encompasses the FORMER POND D Ash Pond System and extends offsite west and POND B southwest. POND A • The vertical extent of affected GW limited by low permeability shal
Slide 24: CCR Constituent: Arsenic
CCR Constituent: Arsenic Arsenic N&E Summary • Arsenic is one of three (3) constituents above Groundwater Protection Standards (GWPS). • Arsenic is the least mobile of the three (3) constituents identified in this group. • For that reason, the extent of arsenic above GWPS is limited to a shallow seg
Slide 25: CCR Constituent: Lithium
CCR Constituent: Lithium Lithium N&E Summary • Lithium is one of three (3) constituents above Groundwater Protection Standards (GWPS). • Lithium is relatively mobile in the environment and has been detected at concentrations above the GWPS in each of the three flow zones, primarily in the immediate
Slide 26: CCR Constituent: Molybdenum
CCR Constituent: Molybdenum Molybdenum N&E Summary • Molybdenum is one of three (3) constituents above Groundwater Protection Standards (GWPS). • Like Lithium, Molybdenum is relatively mobile in the environment and has been detected at concentrations above the GWPS in each of the three flow zones, p
Slide 27: Implications of N&E Findings
Implications of N&E Findings FORMER POND C POND E • Although groundwater results indicate levels FORMER POND D above drinking water standards for arsenic, POND B lithium, and molybdenum, there is no use of POND A groundwater for drinking water on or downgradient of the EVGS site. • Furthermore, site
Slide 28: Risk Evaluation Summary
Risk Evaluation Summary • What work was performed? – Reviewed the analytical data at the Site and Site vicinity using EPA tools; – Identified the pathways by which people and the environment could potentially come in contact with groundwater; – Evaluated if the pathways could cause an adverse impact
Slide 29: Corrective Measures Assessment (CMA): Background & Process
Corrective Measures Assessment (CMA): Background & Process
Slide 30: What is a Corrective Measures Assessment (CMA)?
What is a Corrective Measures Assessment (CMA)? • When levels of constituents in groundwater are found to be above the groundwater protection standards, the CCR Rule calls for corrective measures to be evaluated. • The Corrective Measures Assessment evaluates potential corrective measures that can b
Slide 31: CCR Rule Groundwater Monitoring Program & CMA Development
CCR Rule Groundwater Monitoring Program & CMA Development (40 CFR 257) Corrective Measures Assessment Process Exceedance of GWPS Triggers N&E Groundwater Investigations and Assemble List of Corrective Measures Viable Remedial Monitoring Assessment Options Detection Screen remedial Monitoring N&E opt
Slide 32: Background - Why was the CMA updated?
Background - Why was the CMA updated? • The CMA and associated report were updated to account for the supplemental information collected since 2019. That supplemental information is sourced from: – additional monitoring data and groundwater N&E investigations, – conceptual site model development and
Slide 33: Groundwater Corrective Measures/Remedy Diagram
Groundwater Corrective Measures/Remedy Diagram Groundwater (GW) Treatment Measures Source Control Measures • Ex-situ (above ground) Hydraulic Controls • Hybrid Closure in Place (HCIP) Pump • Closure by Removal (CBR) Pump & Treat (e.g., reverse osmosis) Remedial • In-situ (treatment in the ground
Slide 34: Source Control (Closure) Measures
Source Control (Closure) Measures Soil Cover Detail 6” Topsoil Hybrid Closure in Place will minimize infiltration into the CCR and restrict potential for leaching • Removal of CCR in potential contact with seasonal high groundwater (GW) • Backfill areas where CCR was Culvert removed with clean soil
Slide 35: Source Control (Closure) Measures
Source Control (Closure) Measures Closure by Removal • Excavate CCR and place into dump trucks • Transport CCR material to an offsite landfill • Regrade area (focus on eliminating steep and or unsafe slopes) and promoting drainage of stormwater runoff 35
Slide 36: Groundwater Treatment Measures
Groundwater Treatment Measures In-situ (treatment in the ground) • Monitored Natural Attenuation • Reagent injection • Air sparging Ex-situ (above ground) Hydraulic Controls • Pump Groundwater Extraction wells • Pump & Treat (e.g., reverse osmosis) Water moves Groundwater Biodegradation Sorption tow
Slide 37: Impacted Groundwater Areas of Interest (AOI)
Impacted Groundwater Areas of Interest (AOI) Areas of Interest (AOI) are used to designate portions of the impacted groundwater based on the CCR constituents above the GWPS [Arsenic, Lithium, Molybdenum] and the location on the site [within or outside of the influence of the natural gas plant produc
Slide 38: Summary of Remedial Alternatives
Summary of Remedial Alternatives Supplemental Pumping Wells POND C Groundwater Treatment POND B Alternative Number Source AOI 2 Remedial Alternative PON POND A Control DA AOI 1 AOI 2 AOI 3 AOI 4 AOI 4 AOI 1 Hybrid Closure in Place with AOI 3 Groundwater Groundwater Final Cover and Hydraulic Pumping
Slide 39: Corrective Measures Assessment (CMA): Analysis and Results
Corrective Measures Assessment (CMA): Analysis and Results
Slide 40: How are the Remedial Alternatives Evaluated? Threshold Criteria
How are the Remedial Alternatives Evaluated? Threshold Criteria (Minimum Requirements) Remedies must: (1) Be protective of human health and the environment; STEP 1: Potential (2) Attain the groundwater protection standard as specified All five of the remedial alternatives pursuant to §257.95(h); Thr
Slide 41: How are Remedial Alternatives Evaluated? Balancing Criteria
How are Remedial Alternatives Evaluated? Balancing Criteria (Effectiveness and Performance) (1) The long- and short-term effectiveness and protectiveness of the potential remedy(s), along STEP 2: Once these The four Remedial with the degree of certainty that the remedy will remedial alternatives pro
Slide 42: Summary of CMA Balancing Criteria Analysis
Summary of CMA Balancing Criteria Analysis Balancing Criteria #1 - The long- and short-term effectiveness and protectiveness of the remedy(s), along with the degree of certainty that the remedy will prove successful. • Each remedial alternative involves ongoing pumping at the natural gas plant produ
Slide 43: Summary of CMA Balancing Criteria Analysis
Summary of CMA Balancing Criteria Analysis Balancing Criteria #2 - The effectiveness of the remedy in controlling the source to reduce further releases. • Hybrid Closure in Place and Closure by Removal (CBR) effectively minimize the risk of further releases by isolating CCR onsite above the seasonal
Slide 44: Conclusion and Next Steps
Conclusion and Next Steps “ALBRICH
Slide 45: Process from completion of the CMA to Selection of Remedy
What is the process to move from completion of the CMA to Selection of Remedy? Selection of Remedy Process Selection of Remedy 45
Slide 46: Next steps
Next steps The comment period Comments can be Public comments for the CMA will be submitted via the will be considered, open for 30 days. public meeting per the CCR Rule, in website. the Selection of Remedy process. https://www.aesindiana.com/ eagle-valley-cma-meeting 46
Slide 47: Comments and Discussion
47 Comments and Discussion https://www.aesindiana.com/eagle-valley-cma-meeting May 8, 2024