H. F. LEE ENERGY COMPLEX RISK CLASSIFICATION

Transcription

1 H. F. LEE ENERGY COMPLEX RISK CLASSIFICATION H. F. Lee Energy Cmplex Overall Risk Classificatin DEQ has prpsed the risk classificatin fr the Active Ash Pnd, Plishing Pnd, Inactive Ash Pnd #1, Inactive Ash Pnd #2, and Inactive Ash Pnd #3 as INTERMEDIATE. Grundwater Key Factr. Based n the infrmatin received t date, there appears t be n dwngradient receptrs lcated 1,500 feet dwngradient f the impundment cmpliance bundary. Surface Water Key Factr. The impundments are lcated within the 100-year fldplain. Dam Safety Key Factr. The impundments received a lw r high risk ranking befre any repairs are made and a lw risk rating nce repairs are made. Cal Ash Plant, Operatins, and CCR Impundment Descriptin Summary (frm CSA Reprt) NPDES Permit N.: NC Cunty: Wayne Plant Status: Retired Number f Impundments: 5 (Active Ash Pnd, Plishing Pnd, Ash Pnd #1, Ash Pnd #2, Ash Pnd #3) Duke Energy wns and perates the H.F. Lee Energy Cmplex (Lee Plant) lcated at 1199 Black Jack Church Rad, Gldsbr, Nrth Carlina. The prperty encmpasses apprximately 2,100 acres, including the apprximately 314-acre ash H. F. Lee Energy Cmplex Page 55 f 148 January 29, 2016

2 basins (171-acre inactive ash basins and 143-acre active ash basin). The Lee Plant began cmmercial peratin in Three cal-fired units were retired in September 2012 fllwed by installatin f fur il-fueled cmbustin turbine units in Octber In December 2012, the H.F. Lee Cmbined Cycle Plant was brught n-line. The Cmbined Cycle Plant uses cmbustin and steam turbines t cnvert natural gas t electricity. Cal ash has been managed in the Plant s n-site ash basins, which include three inactive ash basins lcated t the west f the plant peratins area, an active ash basin and Lay f Land Area (LOLA) nrtheast f the peratins area. The ash basins and the LOLA cmprise the ash management areas. Surce Characterizatin Summary (frm CSA Reprt) Cal Ash. Furteen cnstituents were detected abve RSLs in the ash samples cllected frm within the ash basins. Six cnstituents (barium, beryllium, cpper, lead, mercury, and selenium) exceeded the RSL Prtectin f Grundwater in the active ash basin, five cnstituents (barium, beryllium, cpper, lead, and selenium) exceeded the RSL Prtectin f Grundwater in the LOLA, five f the cnstituents (barium, beryllium, lead, mercury, and selenium) exceeded the RSL Prtectin f Grundwater in the inactive basins. Five cnstituents (aluminum, antimny, cbalt, irn, and vanadium) exceeded the RSL Residential Health in the active ash basin, six cnstituents (aluminum, antimny, cbalt, irn, manganese and vanadium) exceeded the RSL Residential Health in the LOLA, five f the cnstituents (aluminum, antimny, cbalt, irn, and vanadium) exceeded the RSL Residential Health in the inactive basins. Arsenic and thallium exceeded the RSL Industrial Health in each f the three areas. Arsenic, barium, brn, cbalt, irn, manganese, thallium, and vanadium were detected abve crrespnding 2L Standard r IMAC in the active ash basin. Antimny, arsenic, brn, cbalt, irn, manganese, selenium, thallium, and vanadium were detected abve crrespnding 2L Standard r IMAC in the inactive ash basin. Antimny, arsenic, barium, cbalt, irn, manganese, thallium, and vanadium were detected abve crrespnding 2L Standard r IMAC in the LOLA area. Ash Leachate. Aluminum, barium, brn, irn, and vanadium were the nly COIs detected at cncentratins exceeding 1 milligram per liter (mg/l) in leachate frm the samples. Ash Pre Water. Elevated cncentratins f calcium, ptassium, magnesium, sdium, bicarbnate, chlride, and sulfate were detected in the samples f ash pre water. H. F. Lee Energy Cmplex Page 56 f 148 January 29, 2016

3 Grundwater Risk Classificatin Key Factr Based n the data prvided in CSA Reprt and results f the grundwater mdeling results presented in the CAP Reprt, the number f dwn-gradient receptrs (well users) 1,500 feet frm the cmpliance bundary that are ptentially r currently knwn t be expsed t impacted grundwater frm surce(s) r migratin pathways related t the CCR impundments: Active Ash Pnd. LOW RISK. There are n reprted supply wells within 1,500 feet dwngradient f the impundment cmpliance bundary. Plishing Pnd. LOW RISK. There are n reprted supply wells within 1,500 feet dwngradient f the impundment cmpliance bundary. Ash Pnd #1. LOW RISK. There are n reprted supply wells within 1,500 feet dwngradient f the impundment cmpliance bundary. Ash Pnd #2. LOW RISK. There are n reprted supply wells within 1,500 feet dwngradient f the impundment cmpliance bundary. Ash Pnd #3. LOW RISK. There are n reprted supply wells within 1,500 feet dwngradient f the impundment cmpliance bundary. Surface Water Risk Classificatin Key Factr This figure depicts landscape psitins in regard t the 100-year fld level, CCR impundment lcatin and river valley fldplain fr the Active Ash Pnd and Plishing Pnd, Ash Pnd #1, Ash Pnd #2, and Ash Pnd #3 at H.F. Lee Energy Steam Electric Plant. H. F. Lee Energy Cmplex Page 57 f 148 January 29, 2016

4 Landscape Psitin and Fldplain: Active Ash Pnd. HIGH RISK. The ftprint f the CCR impundment is sited alng the Neuse River and is lcated in the 100-year fldplain. Plishing Pnd. HIGH RISK. The ftprint f the CCR impundment is sited alng the Neuse River and is lcated in the 100-year fldplain. Ash Pnd #1. HIGH RISK. The ftprint f the CCR impundment is sited alng the Neuse River and is lcated in the 100-year fldplain. Ash Pnd #2. HIGH RISK. The ftprint f the CCR impundment is sited alng the Neuse River and is lcated in the 100-year fldplain. Ash Pnd #3. HIGH RISK. The ftprint f the CCR impundment is sited alng the Neuse River and is lcated in the 100-year fldplain. Dam Safety Risk Classificatin Key Factr State f Structural Stability and Maintenance: Active Ash Pnd (WAYNE-022). HIGH RISK befre repairs are made. LOW RISK after repairs are made. This impundment received a ntice f deficiency with structural deficiencies. The fllwing mdificatins/repairs t the dam have been submitted and H. F. Lee Energy Cmplex Page 58 f 148 January 29, 2016

5 shuld be cmpleted, as a minimum: vegetatin remval, slpe repair, grut pipe, and installatin f a new spillway. Plishing Pnd (WAYNE-034). LOW RISK. This impundment received a ntice f inspectin. The fllwing mdificatins/repairs t the dam have been submitted and shuld be cmpleted as a minimum: remval f mature trees. Ash Pnd #1 (WAYNE-031). LOW RISK. This impundment received a ntice f inspectin. The fllwing mdificatins/repairs t the dam have been submitted and shuld be cmpleted, as a minimum: remval f mature trees. Ash Pnd #2 (WAYNE-032). LOW RISK. This impundment received a ntice f inspectin. The fllwing mdificatins/repairs t the dam have been submitted and shuld be cmpleted, as a minimum: remval f mature trees, slpe repair, and pipe remval near crest and crest repair. Ash Pnd #3 (WAYNE-033). LOW RISK. This impundment received a ntice f inspectin. The fllwing mdificatins/repairs t the dam have been submitted and shuld be cmpleted, as a minimum: remval f mature trees and pipe remval near crest and crest repair. H. F. Lee Energy Cmplex Page 59 f 148 January 29, 2016