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Project Background. Fly ash release from Ash Basin 4 (August 23, 2005)Failure of wooden stop log component within discharge structureDischarged mixture of water and fly ash (est. 100 Mgal)Resulting ash deposition onto PPL owned lands, bed of Oughoughton Creek and into Delaware River (in vicinity of discharge structure)Emergency ash recovery activities commenced immediately after release discoveredDischarge structure was subsequently redesigned and repaired by PPL.
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1. Delaware River Fly Ash Recovery Project
3. Emergency Response Activities Summary
4. Emergency Response Activities Summary Phase III – Vacuum dredging of Pools 1 and 2
Ash identified in two primary locations (Pools 1 & 2)
Vacuum dredging allows precision removal of material with diver operated vacuum nozzles
All material transported to Basin #4 for disposal
Several high-flow events temporarily suspended activities due to unsafe river conditions
Reassessment completed after each high-flow event
Bi-monthly reports submitted to PA DEP
Estimated project completion by mid-March 2006
5. Delaware River Hydrologic RecordRiver Flow Before and After Accidental Fly Ash Release
6. Investigation Program Summary Within 1 month of event, the following investigations were initiated
River Bank Assessment
Shoreline Reconnaissance Program
Diver Assisted Channel Assessment
Sediment and Substrate Assessment
Bioassessment
Residential Well Sampling Program
River Water Quality Sampling
The Diver Assisted Channel Assessment was repeated after both the October and January high flow events
Ash presence assessed through visual observations (gray material) and through presence of elevated Arsenic levels (see next slide)
Arsenic = Indicator Metal
7. Investigation Summary Three major assessment programs
Delaware River Assessment (BBL)
Sediment, biological, scrape, etc.
Delaware River – Water Quality Assessment (ESI)
Metals analysis only
Residential Well Assessment (ESI)
Metals analysis only
8. Delaware River Assessment Through November 2005
Upstream of Pool 2
All but 2 samples (12.7 ppm and 56.6 ppm) had arsenic concentrations comparable to background levels (below 7 ppm)
T0-1 (56.6 ppm) sample locations removed during Phase III work
Downstream of Pool 2
Minimal ash encountered below Pool 2
Limited visual observations and chemical identification
Arsenic levels near background levels with a decreasing trend
Above Lehigh little potential for biological uptake of metals (as indicated by ?SEM)
Significant increase in metals (unrelated to fly ash) and ?SEM below Lehigh
?SEM or Simultaneously Extracted Metals is a way to measure the potential for metals uptake or biological toxicity
9. November 2005 (Post-Storm) Sum of Simultaneously Extracted Metals in Delaware River Sediment Samples
10. Arsenic Concentrations in Sediment Samples Collected in November 2005 (Post-Storm)
11. Data Summary Report (DSR)
Work Summary
Eight separate investigations conducted
Approximately 41 miles of river investigated
Approximately 210 locations were observed and/or sampled
DSR submitted to PA DEP (January 29th) Delaware River Assessment
12. Delaware River Assessment Short-term Biological Assessment
Conducted an assessment based on EPA’s Rapid Bioassessment Protocol looking for acute affects
Assessed fish communities, fish tissue and macroinvertebrates in both pool and riffle-run habitats
Initial assessment done 6-13 days after the spill
Sample stations extended from upstream of the spill to 30 miles downstream
Follow-up assessment was conducted in late September at three sample locations. One location was new
September data were remarkably similar to August data
The new location – a riffle closer to the spill site – showed results very similar to the reference location
13. 2006 Biological Monitoring Program Objective - To assess potential impacts to:
fish communities
benthic macroinvertebrate communities
periphyton communities
Sampling will be done in pool and riffle habitat
Sampling from Belvidere to Easton
Fish tissue analysis will be done on smallmouth bass, white suckers and darters
Evaluations of the community data and the tissue data will use a statistical approach
Possible mussel community study as well
14. Sampling Methodology Determine if observations made from downstream data compare to observed upstream data.
Fish tissue analysis will be done on those species that will best show the potential for bioaccumulation.
Darters were specifically selected because they have smaller home ranges, more rapid uptake of metals and a potential food source for larger predators.
Shad are not a good indicator of any potential impact since they are migratory. If metals were found in the tissue, it could not be determined in what location those metals were ingested.
15. Surface Water Quality Study
16. Surface Water Samples have been collected routinely during the project.
Intent was to monitor river water for metallic constituents of concern found in the fly ash
Samples were analyzed for TAL metals, plus molybdenum, boron, strontium, less potassium and sodium
Sampling started on 08/25/2005 and continues to-date
Samples frequency adjusted as data is received and conditions change
Storm water sampling events increased from 10/8/2005 to 10/16/2005 to determine the effect of the storm event on fly ash movement Surface Water Quality Study (cont.) Explain SEMExplain SEM
17. Surface Water Quality Study (cont.) Routine testing included a representative series of sampling points from above the PPL outfall point downstream to the EWA intake. These included MC Up River, PPL Boat Launch (and modified location), MC FC Access, PAFC Boat Launch, EWA intake, and EWA Finished.
Additional sampling locations were added during the storm event to aid in monitoring ash migration downstream of Easton.
These additional locations included Bristol Aqua PA, Burlington City, Morrisville, New Hope, Tri-County, and Yardley.
Additional locations were also added during the post-storm period of 10/24/2005 to 10/26/2005. These included Lehigh Access and Reigelsville.
18. Surface Water Quality Study (cont.) Sampling frequency changed depending on project needs, recovery activities and safety/weather conditions January bi-weekly event coincided wit Jan storm event. Timed wit Peak of flow and past data did not show a concern based on Oct results…. Large areas of ash in Oct event did NOT cause an issue…….
Boron and Strontium are secondary ash indicating metals
Potassium and sodium not ash indicatorsJanuary bi-weekly event coincided wit Jan storm event. Timed wit Peak of flow and past data did not show a concern based on Oct results…. Large areas of ash in Oct event did NOT cause an issue…….
Boron and Strontium are secondary ash indicating metals
Potassium and sodium not ash indicators
19. Surface Water Quality Study (cont.) Summary of Sampling Results: (Chapter 16 Standards)
Samples collected within 48 hours of release DRBC Zone 1D is the area we are in and same as Chpt 16DRBC Zone 1D is the area we are in and same as Chpt 16
20. Surface Water Quality Study (cont.)
21. Surface Water Quality Study (cont.) No exceedances of 50 PPB drinking water standards and no Chpt 16 standards currently exist for SeleniumNo exceedances of 50 PPB drinking water standards and no Chpt 16 standards currently exist for Selenium
22. Surface Water Quality Study (cont.)
23. Residential Well Assessment
24. Residential Well Assessment (cont.) Sampling conducted primarily to reassure public that the ash release did not affect residential wells.
Residents in both PA and NJ are offered water quality testing; these were primarily in Lower Mount Bethel Township, PA and Harmony Township, NJ
Data supports “no pathway” and “no source”
The sampling program will run from 8-05’ through 8-07’
To date, three rounds of samples have been collected in PA and NJ
There are approximately 230 households in the program
Every quarter the residences are contacted via a mailer to determine if they want to have their well tested
Not all households have chosen to participate for every event
25. Residential Well Assessment (cont.) Well Samples are analyzed for primary and secondary drinking water metals
Metals only (i.e. no VOC’s, biological, nitrates, etc)
Water is collected pre-filter or pre-softener systems
343 well samples collected as of 1/15/2006.
Several exceedances were noted for aluminum, copper, iron, lead, and manganese.
Exceedances not related to ash release
26. Residential Well Assessment (cont.)
27. DSR – Summary
Analysis shows little or no ash effects below Pool 2
Chemical analysis indicates low chemical constituent concentrations near background levels
Visual observations (sample cores, videos, etc.) show no recoverable ash pockets beyond those identified in Pools 1 & 2
Lehigh River is a major source of arsenic and other metals loading not related to ash release
November sampling shows strong indication of natural recovery Conclusions
28. Conclusions (cont.) River Surface Water - Summary (Chapter 16 Standards)
Exceedances resulting from ash release noted only in first 48 hours from samples collected at discharge point.
40 sampling events completed in first 48 hours
Samples contained very high TSS (likely ash)
Exceedances consisted of 4 arsenic and 1 selenium excursions
One exceedance noted in sampling events conducted 48 hours after release to-date.
2,300+ sampling events completed to-date
A single exceedance for mercury noted (Chpt 16 only)
Mercury data point was anomalous with PQL 0.2 ppb
29. Conclusions (cont.) Residential Well Sampling - Results Summary
None of the 343 sampling events showed an impact resulting from the ash release
Several samples indicated exceedances of federal drinking water standards
(8) Aluminum exceedances
(1) Copper exceedance
(16) Iron exceedances
(7) Lead exceedances
(9) Manganese exceedances
Metals detected within residential wells are typical of groundwater in the area and expected metals constituents within older plumbing systems
30. Phase IV – Data Collection & Reporting
Work Plan for future investigations submitted to PADEP (February 6th)
Additional investigations are proposed to fill data gaps and bring project to closure
Additional riverbank sediment sampling, confirmatory sediment sampling, and biological monitoring
Results will be used to determine what, if any, further actions may be required
Residential well sampling to continue until 8-07’ Future Activities