| Action Date |
Action |
Description |
DEC Staff |
| 1/17/1986 |
Update or Other Action |
In 1986, soil samples collected 3 inches bgs to 6 feet bgs from the warm storage building area contained oil and grease up to 8,830 mg/kg and PCBs up to 41 mg/kg. The highest PCB soil samples were collected from the surface. |
Former Staff |
| 2/13/1992 |
Update or Other Action |
ADEC received the Municipal Light and Power 1964 Fuel Oil Spill Generation Plant NO. 1 submitted by Stone & Webster Engineering dated February 13, 1992. Nine soil borings were advanced with five completed as monitoring wells. Groundwater was encountered 2.5 to 8.5 feet bgs. The nine soil borings contained TPH up to 9,080 mg/kg, PCBs up to 73 mg/kg, PCE up to 0.38 mg/kg and TCE up to 0.03 mg/kg. (Note: PCE and TCE were detected in the surface soil 0.5 ft. bgs at boring B-9. PCE was detected from a depth of 0.5 to 11.5 ft. bgs at boring B-7.) Groundwater from the five monitoring wells contained BTEX and PCBs up to 0.023 mg/L. Chlorinated solvents were not analyzed in the groundwater. |
Former Staff |
| 6/30/1992 |
Update or Other Action |
(Old R:Base Action Code = RAPR - Remedial Action Plan Review (CS)). Planned burn of low level contamination PCB soils and sought ADEC input. Letter fro ADEC outlined Department's limited role in handling PCB, Toxic Substances Control Act regulated by EPA. Followup letter to Alaska Pollution Control cc ADEC put very strict limits on PCB testing and burn level limits. |
Former Staff |
| 7/20/1992 |
Update or Other Action |
(Old R:Base Action Code = CORR - Correspondence (General)). The original report was submitted on February, 1992. During reviews and meetings, NOR letter was delayed as the real time problems for addressing TPH and later PCB contamination were handled first. |
Former Staff |
| 7/27/1992 |
Site Added to Database |
|
Former Staff |
| 12/14/1992 |
Site Ranked Using the AHRM |
Initial ranking. |
Former Staff |
| 9/14/1994 |
Update or Other Action |
On this date, ADEC received the PCB field Screening and Testing ML&P No. 1 First Ave & Ingra submitted by S&W and dated July 1994. Ten test holes were advanced to a depth of 3 feet bgs at the proposed pipe trench area across the driveway of the ML&P Plant 1. The soil samples contained DRO up to 28,000 mg/kg and PCBs less than 1 mg/kg. |
Former Staff |
| 1/9/1996 |
Update or Other Action |
ADEC letter reviewing "Characterization and Remediation Alternatives Study at a Diesel Spill Site," of January 1995. ADEC requested additional site characterization |
Eileen Olson |
| 11/13/1996 |
Update or Other Action |
On this date, ADEC received the Off-site Characterization Study at the ML&P 1st Ave Power Plant No. 1 site submitted by Meta Environmental and dated October 1996. Soils samples were collected from 15 borings and groundwater samples were collected from historic and new MWs. The results indicate the impacts of the 1964 diesel spill were greatest at the near source location southwest of Power plant 1 with a smear zone at about 5 to 9 feet bgs. Impacts to the soil and GW extended primarily to the SW, W and NW of the Plant. Concentrations of contaminants decreased in samples collected down gradient towards Ship Creek. |
Former Staff |
| 1/21/1997 |
Update or Other Action |
Date of ADEC letter reviewing "Off-Site Characterization Study at the Municipal Light and Power First Avenue Power Plant Number 1 Site". ADEC requested characterization of off-site groundwater contamination. |
Eileen Olson |
| 4/23/1999 |
Update or Other Action |
Date of ADEC letter requesting site-wide groundwater monitoring event |
Eileen Olson |
| 8/9/1999 |
Update or Other Action |
Approved workplan of August 2, 1999 for site-wide groundwater monitoring event; |
Eileen Olson |
| 1/29/2004 |
Update or Other Action |
File number changed from CS69.30 to 2100.38.326. |
Sarah Cunningham |
| 2/2/2004 |
Update or Other Action |
ADEC sent letter to Lena Savile of ML&P after review of the November 1999, Groundwater Monitoring report. In the letter ADEC requested continued groundwater monitoring in accordance with the already approved workplan. Free product recovery from monitoring well B3 and the assessment of possible impacts to Ship Creek was also requested. |
Beatrice Egbejimba |
| 3/3/2004 |
Update or Other Action |
In response to ADEC’s February 2, 2004 letter, Lena Savile of ML&P sent an e-mail containing information regarding the status of the monitoring wells at this site.
Based on this information and subsequent phone calls, ADEC learned that monitoring well B-3 and the 4-inch recovery well had been located. Other wells were not located because of the substantial thickness of snow and ice on the ground. Shannon and Wilson was present to removed the passive skimmers that were installed in 1994 in B-3 and the 4-inch recovery. No free product was observed in the system however, the skimmers will be cleaned and evaluated for effectiveness of product recovery. It is suspected that Monitoring Well MW23 was destroyed during site reconstruction at 800 E. Ship Creek Avenue in 2001-2002. ML&P cannot verified this information before snow/ice melts. ADEC has requested the monitoring of all wells associated this investigation by June 2004. |
Beatrice Egbejimba |
| 3/10/2004 |
Update or Other Action |
ADEC approved a workplan for free product recovery in monitoring well B-3 submitted by Yelena Savile of ML&P. Hydrophobic absorbent socks Rubberizer would be used to recover any free product present in the well. Weekly inspections will take place to measure and pump any free product observed in monitoring well MW-3 and the adjacent 4-inch Recovery well. No information was provided regarding the disposal of absorbent socks at the time workplan review. The approval was condition on ML&P' s submittal of this information. |
Beatrice Egbejimba |
| 3/23/2004 |
Update or Other Action |
ADEC received disposal information for the absorbent socks as requested in the March 10, 2004 letter to ML&P. ML&P proposes to store the sock and other oily soilds in metal drums upon removal from monitoring well for incineration by Safety Waste Incineration. |
Beatrice Egbejimba |
| 3/26/2004 |
Update or Other Action |
Staff received copy of application for Bronwnfields Funding submitted to DEC Target Brownfileds Assessment section un Juneau. ML&P requested funding for the cleanup and redevelopment of the contaminatred site located on 821 East First Avenue. |
Beatrice Egbejimba |
| 3/30/2004 |
Update or Other Action |
Staff reviewed report by Shannon & Wilson entitiled Product Recovery Assessment. The report provided information regarding an investigation that took place to assess current product thickness and recoverability of the product. Shannon & Wilson concluded that product layer was thin and limited to the MW-B3 area. ADEC will evaluate the need for continued product recovery using hydrophobic absorbent socks Rubberizer when data becomes available. |
Beatrice Egbejimba |
| 5/9/2004 |
Update or Other Action |
ADEC received letter from Department of Law indicating that a check on behalf of ADEC was received from Municipal of Anchorage for cost recovery ($320.04). |
Beatrice Egbejimba |
| 6/2/2004 |
Update or Other Action |
ADEC reviewed the workplan for additional site characterization and groundwater sampling for M L& P Plant 1. The Plan proposes to install three wells along the ship creek. Following installation, these wells will be sampled for diesel range organics along with all the wells associated with this investigation. The activity is aimed at determining potential risk to the nearby surface water body (Ship Creek). ADEC approved the workplan but recommended the relocation of MW37 to a location down gradient of MW24S,D. ADEC met with Lena Savile of M L&P to discuss the new location. Based on the information provided at the meeting, ADEC noted that relocation may not be practicable because new construction has been proposed in the vicinity of the suggested area. |
Beatrice Egbejimba |
| 8/25/2004 |
Meeting or Teleconference Held |
CSP staff met with Lena Seville of ML&P to discuss a request to postpone installation of one monitoring well previously agreed to by Ship Creek until a bike path was completed, and to indefinitely postpone installation of the middle proposed well by Ship Creek because it was recently determined to be in an area of numerous utilities and the area is undergoing continual resurfacing. DEC tentatively agreed to the proposal but requested that a workplan amendment be provided so it could provide a written response to ML&P's request. |
Rich Sundet |
| 6/15/2006 |
Update or Other Action |
GW sampling work plan dated June 14, 2006 for Power Plant 1 with the following comment. With WP approval, a copy of the new ADEC Laboratory QA Policy was included. RP was notified that all samples are now subject to these requirements. |
Linda Nuechterlein |
| 7/19/2006 |
Update or Other Action |
Reviewed and approved a work plan for management of potential soil and groundwater. A construction project to upgrade Power Plant #1 on this ML&P site is scheduled to begin mid-July where it is estimated that approximately 150 cubic yards of contaminated material may be excavated. The site has a history of Polychlorinated biphenyl (PCB) and petroleum hydrocarbon contamination. Although the site is operated by MLP, some of the land is owned by Alaska Railroad Corporation (ARRC). Therefore the site is included in the Environmental Protection Agency (EPA) Consent Order for the Anchorage Terminal Reserve. The management plan for soil and groundwater and is co-ordinated this approval with EPA since the PCB contamination is regulated by the Toxic Substance Contol Act (TSCA.) of 1976 and also regulated under the EPA Order.
|
Linda Nuechterlein |
| 8/16/2006 |
Update or Other Action |
Received report for GW monitoring conducted during June 2006. PCB contamination was detected in GW in one well only, which is attributed to the historic presence of free product in the well as a result of a tank failure during the 1964 earthquake. PCBs have not been found in any other wells on site, so current data indicates there is no off-site transport occurring. |
Linda Nuechterlein |
| 10/11/2006 |
Meeting or Teleconference Held |
Rich Sundet, Jimn Frechione, and Bill OConnell met with ML&P regarding their ongoing excavation for construction related to the upgrade of their facilities near Ship Creek. The facility sits on property that is about 2/3 owned by ML&P and 1/3 Alaska RR lease property and contains historic PCB contamination in the soil over a large portion of the property.
During excavation activities, ML&P found more PCB-contaminated soil than was anticipated. The original workplan anticipated 150 cy, but they currently have approximately 1200 cy stockpiled. The maximum concentration of PCBs detected is 65.3 ppm in stockpiled soil. After finding this quantity of soil, ML&P requested a meeting with ADEC to discuss options.
|
Linda Nuechterlein |
| 10/31/2006 |
Update or Other Action |
GW monitoring plan for Plant 1 dated Oct 27, 2006 approved. Email sent to Yelena Seville. Sampling of six MWs for DRO and PCBs to take place in November 2006. |
Linda Nuechterlein |
| 5/10/2007 |
Meeting or Teleconference Held |
ADEC met with ML&P and their consultants to discuss the results of bottom samples collected from a 2006 excavation during facility upgrades at ML&P Plant #1 near Ship Creek. PCBs were detected in subsurface soil in one sample at 246 mg/kg, exceeding both the ADEC and TSCA maximum allowable levels. ML&P built a concrete pad and turbine on top of this sample location and are therefore out of compliance with ADEC and TSCA regulations. ML&P had been planning additional excavation work for summer 2007, but will re-cost this work in consideration of potential environmental costs to determine if the project is feasible. Additional coordination between ADEC, EPA, ARRC, and ML&P will be ongoing as ML&P moves forward with future excavation plans |
Bill O'Connell |
| 5/22/2007 |
Update or Other Action |
ADEC issued a letter to ML&P describing their responsibilities regarding PCBs in soil at the Plant. EPA and ADEC will be coordinating with ML&P on all future projects to ensure ADEC and TSCA regulations are adhered to. See letter attached to this database for more information. |
Bill O'Connell |
| 9/10/2007 |
Exposure Tracking Model Ranking |
Initial ranking |
Bill O'Connell |
| 2/25/2008 |
Update or Other Action |
In October 2007, ML&P submitted a Risk Based Disposal Plan for PCB contaminated soil to EPA and ADEC for review. EPA responded on this date with a letter providing comments on the RBDP and requesting that the plan be resubmitted after the comments are addressed. |
Bill O'Connell |
| 4/11/2008 |
Update or Other Action |
The revised Risk Based Disposal Plan was approved by EPA on this date. |
Bill O'Connell |
| 1/11/2010 |
Document, Report, or Work plan Review - other |
Reviewed report on PCB analyses of soil samples collected during geotechnical investigation to support 2010 construction activities. Two soil borings were advanced on the east side of the main office and shop building to 40 feet bgs. GW was found at 4.5 feet bgs and the bootlegger cove clay was encountered at 12.5 feet bgs. Samples were collected at two foot intervals from 0-12 feet bgs, then again at 20-22 feet bgs. PCBs above the cleanup level of 1 mg/kg were found as deep as 10-12 feet, with the highest concentration, 131 mg/kg, found at 10-12 feet bgs in borehole TH2. DRO was also detected above the cleanup level at 4-5 feet bgs in TH1 at 2,960 mg/kg and PCE was detected above the cleanup level at 2-4 feet bgs in TH2 at 0.0692 mg/kg. |
Bill O'Connell |
| 1/13/2010 |
Meeting or Teleconference Held |
Meeting today with ML&P, Hoefler, and EPA to discuss construction project slated for 2010 noted in the above action. The presence of PCBs at the geologic contact with the Bootlegger Cove clay is a phenomenon not observed at this location in the past. In order to plan for construction dewatering activities and to evaluate the potential contaminant accumulation at the contact with the Bootlegger clay, ADEC requested a borehole be advanced in this area and completed as a monitoring well that is screened at the contact with the clay, approximately 10-12 feet bgs. |
Bill O'Connell |
| 1/19/2010 |
Document, Report, or Work plan Review - other |
Work plan reviewed for additional investigation near TH-2. One borehole will be advanced into the Bootlegger Cove Clay to confirm/evaluate data collected during recent geotech investigation as noted in the above action. Soil samples will be collected at two foot intervals for lab analysis for PCBs and a monitoring well will be installed that is screened across the Bootlegger Cove clay interface to evaluate this as a depositional zone for PCBs. Groundwater samples will also be collected from wells B-7, B-4, and MW-13 to evaluate PCB concentrations in water in an area likely to be dewatered during 2010 construction activities. The new well, MW-14D, will also be sampled, with samples run through 0.45 and 5.0 micron filters to filter out particleson which PCBs might adhere. |
Bill O'Connell |
| 2/17/2010 |
Document, Report, or Work plan Review - other |
Reviewed January 2010 Soil Sampling and Groundwater Monitoring Report. Sampling was conducted to support construction activities in 2010. One borehole was installed and complete as a monitoring well screened at the base of the shallow aquifer at the contact with the bootlegger cove clay to evaluate the presence of PCBs in soil and groundwater. Groundwater samples collected from this well and from three existing wells did not contain detectable concentrations of PCBs. Soil samples collected at two foot intervals during installation of the new well, MW-14D contained PCBs at each interval above the cleanup level of 1 mg/kg ranging from 1.38 mg/kg at 10-12 feet bgs to 112 mg/kg at 2-4 feet bgs. Construction activities are anticipated to begin in April 2010. |
Bill O'Connell |
| 3/3/2010 |
Document, Report, or Work plan Review - other |
Reviewed Work Plan for Soil Management at Diesel Generator Construction Site: Phase I. Phase I work will consist of installing two subsurface vaults and utility trenching along the eastern side of the Plant 1 facility. Once the vault excavation is complete, soil samples will be collected and analyzed for PCBs in accordacne with the Risk Based Disposal Plan (RBDP). If PCBs are detected above 50 ppm, soil will be removed down to the water table. Excavated soil with PCBs< 10ppm will be used as backfill, soil with PCBs> 10 ppm will be disposed of offsite. Disturbed aeas will be capped with asphalt after contsturction is complete. Dewatering will be conducted using a 20-micron filter to capture entrained sediment that may contain PCBs, and the sediment disposed of in accordance with the RBDP. |
Bill O'Connell |
| 4/7/2010 |
Meeting or Teleconference Held |
Meeting today with ML&P, Hoefler, and EPA TSCA to discuss sampling at Plant 1 during 2010 construction activities. Hoefler will use a 1.5 meter grid to collect composite samples for PCBs, with 4 increments per composite (3m x 3m) |
Bill O'Connell |
| 4/21/2010 |
Site Visit |
Site visit today to observe initial excavation and sampling activities associated with installation of concrete vaults and utilities. |
Bill O'Connell |
| 7/6/2010 |
Update or Other Action |
In accordance with the Risk Based Disposal Approval, a Deed Notice was filed at the ADNR Recorder's office detailing some of the ICs noted in the RBDA and restricting the site to "low occupancy" land use. See attached document for additional details. |
Bill O'Connell |
| 8/6/2010 |
Document, Report, or Work plan Review - other |
Reviewed report for Soil Management Activities at the Diesel Generator Construction Site. Soil management activities were conducted in accordance with the 2008 Risk Based Disposal Plan for PCB contaminated Soil. The project consisted of excavating to below the water table, installation of two concrete utility vaults and trenching for utilities. Excavated soil was placed into bins to await characterization. Wet soil was allowed to dry in a lined containment area and the water was pumped into a tank along with water removed from the excavation. The excavation water was filtered through a 10 micron filter before being discharged to the sanitary sewer in accordance with an AWWU discharge permit. Tank sludge was found to contain PCBs up to 5.5 mg/kg and was shipped offsite for disposal. Approximately 650 cubic yards of soil was excavated and characterized. Approximately 15 cy of soil contained PCBs above 50 mg/kg and was shipped offsite for disposal, along with an additional 460 cy of soil containing PCBs between 0 and 50 mg/kg that was unsuitable for use as backfill. Approximately 175 cy of soil containing PCBs less than 10 mg/kg was used as backfill. Confirmation samples collected at the base of all excavations contained PCBs up to 12.1 mg/kg. As part of the excavation work, monitoring well B-4 was removed. |
Bill O'Connell |
| 4/8/2011 |
Document, Report, or Work plan Review - other |
Reviewed Soil Management At the Diesel Generator Construction Site Work Plan for 2001 construction activities at ML&P Plant 1. Construction activities will be conducted within the Plant 1 facility and also outside of the facility to the north, west, and south. Activities conducted within the Plant 1 boundary will be in accordance with the 2008 Risk Based Disposal plan approved by EPA. Excavated soil will be stockpiled and sampled for PCBs. Soil with PCBs greater than 1 mg/kg will be disposed of at a TSDF in the Lower 48. Bottom samples will be collected from the bottom of the excavations and if PCBs greater than 50 mg/kg are detected, soil will be removed until confirmation samples indicate remaining PCB concentrations are less than 50 mg/kg or until the excavation reaches the water table. For areas outside the facility boundary, excavated soil will be placed back into trenches at the approximate elevation from which it was removed. Bottom samples will not be collected. Excess soil that cannot be used as backfill will be sampled for PCBs, VOCs, and potentially DRO/RRO is there is evidence that soils have been impacted by hydrocarbons. The excavations will occur in areas known to be impacted by low levels of chlorinated solvents, and also in an area impacted by RCRA F-listed waste, which some/all is suspected to of originated from the former dry cleaner located at 4th and Gambell. Excess soil will be disposed of in accordance with all applicable regulations likely at a TSDF in the Lower 48, and it is anticipated that a ‘Contained-In’ will be requested from EPA for the F-Listed solvents that may be encountered during excavation. The excavations will be dewatered into tanks then disposed of in the sanitary sewer in accordance with an AWWU discharge permit. Sediment that settles out will be sampled and likely disposed of along with other impacted soil from the site. |
Bill O'Connell |
| 4/18/2011 |
Document, Report, or Work plan Review - other |
Reviewed Work Plan for groundwater monitoring at Plant 1. Samples will be collected from wells MW-12s, MW-13s, MW-7, MW-9, and MW-28 and analyzed for DRO, BTEX and PCBs, MW-28 will also be analyzed for VOCs. |
Bill O'Connell |
| 4/27/2011 |
Meeting or Teleconference Held |
Meeting today with ML&P, SLR, and Region X EPA to discuss Contained In request for F-Listed solvents likely to be encountered in excess soils during excavation activities on the south side of Ingra Ave in 2011. The source of the F-Listed solvents is the former dry cleaner located at 4th and Gambell (Hazard ID 4084). |
Bill O'Connell |
| 8/16/2011 |
Document, Report, or Work plan Review - other |
Reviewed Spring 2011 Groundwater Monitoring Report for Plant 1. Groundwater samples were collected from six monitoring wells and analyzed for DRO, BTEX, and PCBs: MW-28 was analyzed for the full suite of VOCs. Contaminants were detected above cleanup levels in one well, MW-28, which is located outside of the facility to the west across Ingra St. This well contained TCE, PCE, cis-1,2-DCE and vinyl chloride above their cleanup levels. Some/all of the contamination in this well is suspected to be the result of migration from the upgradient former dry cleaner located at 4th and Gambell. Monitoring wells within the facility boundaries did not contain contaminants above cleanup levels. |
Bill O'Connell |
| 7/8/2013 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 79427 name: Upgradient former dry cleaner GW plume |
Grant Lidren |
| 9/9/2013 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 78254 name: Diesel from tank rupture, 1964 |
Grant Lidren |
| 8/25/2014 |
Potentially Responsible Party/State Interest Letter |
PRP letter sent to ML&P on this date |
Grant Lidren |
| 7/15/2015 |
Site Characterization Report Approved |
On this date, ADEC reviewed the Focused Groundwater Characterization, Alaska Real Estate Parking Lot, Anchorage Alaska submitted by Ahtna, dated June 23, 2015. This memo documented additional characterization activities to accompany the FINAL REPORT FOR FOCUSED GROUNDWATER CHARACTERIZATION ALASKA REAL ESTATE PARKING LOT ANCHORAGE, ALASKA ADEC SPAR TERM CONTRACT #18-8036-13 submitted by Ahtna dated September 16, 2014 (see contaminated site file# 2100.38.434 Alaska Real Estate for more info). Work included: acquiring historical photos; retrieving datalogger data from May 2014 to April 2015; and sampling the groundwater from down gradient monitoring wells. The down gradient monitoring wells located adjacent to 1st avenue including: AKRRMW-22; AKRRMW-24S; and MW-B-3 which were sampled for VOCs and 4GMW-13; 4GMW-14; 4GMW-15; and MW-28 which were sampled for GRO, DRO, and BTEX. Only monitoring wells 4GMW-13 and 4GMW-14 - located at the location of the historic 1964 AST rupture - contained contamination above cleanup levels with DRO at 1.6 mg/L and 2.1 mg/L respectively. Groundwater flow was to the northwest and based off data logger data has a hydrological connection to Ship Creek. |
Grant Lidren |
| 10/4/2016 |
Site Characterization Workplan Approved |
On this date, ADEC approved the Work Plan Addendum: Sampling and Analysis Plan (SAP) for the Area North and Outside of the Facility Fence, ML&P Plant 1, which is an Addendum to Work Plan for Soil and Debris Management during the Security Fence Upgrade Project; ML&P Hank Nikkels Plant No. 1; Anchorage, AK (May 16, 2016). This work plan was submitted by SLR and dated September 29, 2016. |
Grant Lidren |
| 8/30/2017 |
Site Characterization Report Approved |
On this date, ADEC received the Site Characterization of the Proposed Asphalt Paving Area and Vicinity Security Fence Upgrade Project ML&P Hank Nikkels Plant No. 1 submitted by SLR and dated January 20, 2017. A total of 84 surface soil samples collected 2 to 4 inches bgs were analyzed for PCBs with six samples analyzed for DRO/RRO. These soil samples were collected from three areas: the area outside the property fence, the paved area, and the unpaved area. In the unpaved area, PCBs were detected above the ADEC cleanup level of 1.0 mg/kg in 26 of the 61 soil samples collected with PCBs up to 1,370 mg/kg. In the paved area, PCBs were only detected in one of the six soil samples collected but below the ADEC PCB cleanup level. Outside the fence, 17 soil samples collected were non-detect up to 0.123 mg/kg. |
Grant Lidren |
| 12/27/2017 |
Document, Report, or Work plan Review - other |
On this date, ADEC received the 2017 PCB-Contaminated Soil Removal ML&P Hank Nikkels Plant No. 1 submitted by SLR and dated December 2017. In preparation of paving, the top 6 inches of soil was removed. Additionally, soil areas that contained PCBs greater than 50 mg/kg were removed to a depth of 2 feet bgs in all locations and an additional 4 feet bgs (6 feet bgs total) at the groundwater interface at one location. The excavations were backfilled with restricted use soil (PCBs < 10 mg/kg) 1 to 6 feet bgs, topped with clean fill 1 foot bgs and capped with 2 inches of asphalt pavement. Final floor confirmation soil samples collected were only collected from the soil areas that contained PCBs greater than 50 mg/kg. These 17 composite soil samples contained PCBs up to 42 mg/kg. A total of 225 cubic yards (278 tons) of PCB impacted soil was shipped to TSDF permitted facilities in Arlington Oregon. These facilities include the Columbia Ridge landfill for non-haz PCB contaminated soil (PCBs < 50 mg/kg) and the Chemical Waste Management of the Northwest for the TSCA contaminated soil (PCBs >50 mg/kg). This field work was conducted in accordance with the 2008 RBDP for PCB contaminated soil (see file). |
Grant Lidren |
| 1/12/2018 |
Document, Report, or Work plan Review - other |
On this date ADEC received the Excavation Work Plan for Removal of PCB-Contaminated Soil, ML&P Plant 1 Asphalt Paving Area submitted by SLR and dated May 8, 2017. This work plan was not approved by ADEC but appears to be in accordance with the Risk Based Disposal Plan approved by EPA on April 11, 2008. |
Grant Lidren |
| 1/28/2021 |
Meeting or Teleconference Held |
DEC staff met with EPA to discuss the ODC RBDP and concerns at the site to gain an idea of how the contamination would be managed with combined regulations. Groundwater monitoring will be conducted with DEC regulations in mind. Capping of the site will be discussed with Chugach Electric by EPA to ensure TSCA regulations will be followed. A covenant under UECA will be recommended by DEC to cover the facility instead of the deed restriction typically used under TSCA. |
Tim Sharp |
| 4/9/2021 |
Document, Report, or Work plan Review - other |
DEC sent comments on the Draft GW Monitoring Plan. Chugach will sample for PCBs in groundwater, and if no PCBs detected, will switch to four year monitoring cycle until RBDP is deemed no longer necessary. DEC recommended sampling for DRO in MW B-3, as free product has been present there previously and historically in that area DRO levels have been highest. |
Tim Sharp |
| 5/28/2021 |
Document, Report, or Work plan Review - other |
DEC Approved the Final GW MP. Well B-3 will be sampled for DRO, and if DRO is measured above CUL will be sampled on a schedule. If DRO is below Table C then it will be dropped from subsequent sampling events. |
Tim Sharp |
| 11/5/2021 |
Document, Report, or Work plan Review - other |
DEC Approved the 2021 Groundwater Monitoring Report, which details the sampling of all present groundwater monitoring wells for PCBs, and monitoring well B-3 was sampled for DRO. Aroclor 1260 was detected in MW-14D, but below Table C cleanup levels. DRO was detected above Table C in B-3, and as such DRO will be included in future monitoring events. Chugach will coordinate with DEC to determine how to characterize and monitor the DRO plume. Wells will be monitored annually for PCBs. |
Tim Sharp |
| 10/21/2022 |
Document, Report, or Work plan Review - other |
ADEC has reviewed the 2022 Groundwater Monitoring Report, which details the methods and results of groundwater monitoring conducted in July 2022 at the Hank Nikkels Plant 1 site. Seven groundwater monitoring wells were sampled for polychlorinated biphenyls (PCBs), and one monitoring well was also sampled for diesel range organics (DRO). No PCBs were detected in any wells at concentrations exceeding state regulatory groundwater cleanup levels, found in 18 AAC 75.345, Table C. DRO was detected above the Table C cleanup level in the well sampled. The report recommends continued annual sampling for both PCBs and DRO in the same wells, scheduled for July 2023. |
Tim Sharp |
| 12/15/2022 |
Document, Report, or Work plan Review - other |
DEC approved the 2022 Ground Water Monitoring Report. The report recommends continued annual sampling for both PCBs and DRO in the same wells, scheduled for July 2023. |
Arika Garcia |
| 3/15/2024 |
Document, Report, or Work plan Review - other |
DEC approved the 2023 Groundwater Monitoring Report. The report recommends continued annual monitoring for PCBs and a new monument cap be put on MW-12S. |
Livia Bracker |
| 10/29/2024 |
Document, Report, or Work plan Review - other |
DEC approved the 2024 Groundwater Monitoring Report for Hank Nikkels Power Plant 1 site. The report recommends continued annual groundwater monitoring for PCBs. |
Livia Bracker |
