| Action Date |
Action |
Description |
DEC Staff |
| 7/24/1991 |
Update or Other Action |
(Old R:Base Action Code = MS - Monitoring/Sampling). Shannon and Wilson sampled monitoring well for GVEA. Benzene found at 2.2 ppb, below MCLs. |
Former Staff |
| 8/9/1991 |
Update or Other Action |
(Old R:Base Action Code = RAPR - Remedial Action Plan Review (CS)). GVEA proposes to excavate 40 - 50 yards of soil beneath the two middle sites of the former generators, the same area which has elevated PID readings of 100 - 200 ppm. They would like to cap the entire site with an asphalt parking lot and use the monitoring well downstream as an indicator of any additional contamination. In the event that MCLs were exceeded, GVEA would conduct a site assessment of the area and install bore holes to determine extent of contamination. Groundwater is at 18 feet. |
Former Staff |
| 8/16/1991 |
Site Added to Database |
Oil contamination - historic spill. |
Former Staff |
| 9/30/1991 |
Update or Other Action |
(Old R:Base Action Code = RAPR - Remedial Action Plan Review (CS)). Reviewed letter of agreement (combination on site assessment and work plan) written by GVEA. Agreement proposes excavating soils to 1000 ppm in accord with cleanup matrix. |
Dan Basketfield |
| 5/12/1992 |
Site Ranked Using the AHRM |
Initial ranking. |
Former Staff |
| 8/6/1992 |
Update or Other Action |
(Old R:Base Action Code = CORR - Correspondence (General)). (SLSW) Final request completed and sent to Juneau for approval included 10 points for Site Assessment: Site History, Monitor Wells, Well Surveys, Water Elevations, Pieziometric Surface, Aquifer Test, Groundwater Analysis and Final Report. Starting date February 1993. |
Cindy Thomas |
| 12/18/1992 |
Update or Other Action |
(Old R:Base Action Code = RPL2 - Site Information Request Letter). PRP notified by letter, party of ADEC's intent to use Response Fund monies to initiate a comprensive area-wide Phase I site Assessment of the Illinois-Minnie Site. Asks to submit questions and comments. |
Cindy Thomas |
| 12/28/1992 |
Update or Other Action |
(Old R:Base Action Code = CORR - Correspondence (General)). (OSLP) Corrections returned to ARRC thanking them for comments. Will incorporate them into the ADEC final version. Will keep ARRC and all parties updated on future actions. |
Cindy Thomas |
| 1/17/1995 |
Update or Other Action |
SITE SUMMARY: Long term GW monitoring is planned for this site for BTEX (and maybe solvents?) by GVEA. Last 2 years of sample dated filed and should be reviewed by new case officer.) MSLUG study effort may shed light on relationship to other sites. |
Cindy Thomas |
| 7/10/2002 |
GIS Position Updated |
Changed the Latitude, Longitude, Method Accuracy, Accuracy and Unit fields. |
Heather Goldman |
| 10/19/2007 |
Update or Other Action |
Received annual GW report. Zehnder well and MW-6 has high levels of PCE, 21ppb, 6ppb respectively. In 2003 MW-1, MW-3, MW-7, MW-AK-Gold-1and MW-(1-3) NER approved for decommission. |
Neal Everson |
| 2/15/2008 |
Update or Other Action |
Staff has reviewed the annual groundwater monitoring report for evaluating the contamination on the property within the context of the entire area's contaminant issues. New monitoring results are expected soon from surrounding sites and these will all be considered together. |
Ann Farris |
| 3/14/2008 |
Cleanup Assumed by ADEC |
Project manager changed from Jim Frechione to Ann Farris. Staff is still awaiting groundwater results from Bentley TL201 and the East Satellite Building to evaluate the solvent issues on an areawide basis. These results are expected by the end of this month. |
Ann Farris |
| 5/5/2009 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 72372 name: diesel tanks for Gas Turbine |
Ann Farris |
| 8/21/2012 |
Update or Other Action |
Discussed groundwater monitoring program with Kris DuBois and reviewed monitoring data. DEC recommended reduction of the groundwater monitoring program to the Zehnder well and MW-6. There is some indication that the PCE concentration in the Zehnder well could be increasing, so also recommended GVEA research possible on-site sources of PCE that may be impacting the Zehnder well. |
Janice Wiegers |
| 9/22/2014 |
Document, Report, or Work plan Review - other |
DEC received Annual Groundwater Sampling report. MW-6 and the Zehnder Well were sampled for VOCs. Contaminants detected above DEC groundwater cleanup levels were cis-1,2-dichloroethene at 1.14 ug/L in MW-6 and tetrachloroethene at 17.4 ug/L in the Zehnder Well. Consultant recommended sampling in fall. |
Janice Wiegers |
| 6/8/2015 |
Potentially Responsible Party/State Interest Letter |
PRP letter sent to Naomi Knight with GVEA. |
Janice Wiegers |
| 9/17/2015 |
Update or Other Action |
Travis/Peterson Environmental Consulting submitted a letter discussing possible sources of PCE on the property. The letter indicates that other drycleaner spills upgradient of the site and/or the documented presence of PCE in Noyes Slough in the past may explain PCE observed in the Zehnder Well (well installed along the north boundary of the property). Groundwater monitoring, which has occurred in this well since 1993, suggest a slightly increasing trend over that time period. PCE results in the past 10 years have ranged from 16 to 25 ug/L. |
Janice Wiegers |
| 9/17/2015 |
Update or Other Action |
Annual groundwater water monitoring report submitted to DEC. |
Janice Wiegers |
| 9/23/2015 |
Document, Report, or Work plan Review - other |
Reviewed and approved workplan to decommission monitoring wells MW2, MW3, and MW4. MW 4 is being decommissioned because it is no longer functioning. |
Janice Wiegers |
| 10/30/2015 |
Document, Report, or Work plan Review - other |
Monitoring Well Decommissioning Report submitted. MW-2, MW-3, and MW-4 were decommissioned. The well casings were removed and filled with a bentonite slurry. |
Janice Wiegers |
| 1/22/2016 |
Update or Other Action |
DEC sent letter to GVEA requesting workplan within 90 days to further evaluate solvent contamination. |
Janice Wiegers |
| 5/11/2016 |
Update or Other Action |
Contacted by TPECI regarding the recent letter to GVEA. TPECI is working on a workplan that they plan to submit by May 20. |
Janice Wiegers |
| 5/26/2016 |
Document, Report, or Work plan Review - other |
Received letter from TPECI responding to DEC request of 1/22/16. Records research indicated Chemsearch SS-80 was used by the electric shop personnel for degreasing transformers in the field and in the shop. Use of this chemical was discontinued more than 10 years ago. The letter also provided information on the land ownership since 1914. The United States Smelting, Refining and Mining Company (USSR&M) operated a coal-fired power plant on the property until it was sold to GVEA in 1953. The letter indicates that planning for soil and groundwater sampling to investigate possible on-site solvent sources will be put on hold until a report on areawide sources is completed through the nearby Bentley Mall East Satellite Building site. |
Janice Wiegers |
| 7/14/2016 |
Update or Other Action |
Received letter from TPECI indicating that they do not believe anything other than monitoring at MW-6 and the Zehnder will is required of GVEA. This response was based on the report submitted by the Environmental Resources Group for contamination associated with the Bentley Mall East Satellite Building (Hazard ID 4033; file number 102.38.122). |
Janice Wiegers |
| 7/26/2016 |
Update or Other Action |
Letter sent to GVEA requesting additional investigation to clarify sources of PCE observed in groundwater. Workplan requested by August 20th. |
Janice Wiegers |
| 8/21/2016 |
Update or Other Action |
Received letter from GVEA indicating they do not feel a scientifically-defensible workplan could be developed in the amount of time requested in the July 26, 2016 letter from DEC. GVEA indicated groundwater sampling was conducted on August 17th, and MW-7 was added to the wells sampled. On August 18th, Bud Hilton's Thawing, Pumping and Backhoe Service used a down-hole camera to verify the screen location in the Zehnder well. The screen was observed at 21.7 to 24.5 feet. |
Janice Wiegers |
| 8/31/2016 |
Document, Report, or Work plan Review - other |
Received groundwater monitoring report for data collected on August 17, 2016. Samples were collected at the Zehnder well, MW-6, and MW-7. PCE exceeded DEC cleanup levels in the Zehnder well at 26.3 ug/L and in MW-6 at 8.27 ug/L. TCE exceeded cleanup levels in MW-6 at 5.1 ug/L. The highest levels of TCE observed in MW-6 prior to this sampling event at 2.8 ug/L. |
Janice Wiegers |
| 11/14/2016 |
Document, Report, or Work plan Review - other |
Received letter report from GVEA regarding groundwater gradient information and screen depths of three monitoring wells using a camera. The screen for the Zehnder well, which contains the highest concentration of solvents, was located about 7 feet below the water table. GVEA suggested this was the reason for higher concentrations in the Zehnder well than in MW-6 or MW-7. Groundwater flow direction was to the NE on 9/15/16, which is unusual. Requested field notes to verify groundwater elevation data. |
Janice Wiegers |
| 3/6/2017 |
Meeting or Teleconference Held |
DEC met with GVEA and TPECI to discuss moving forward with DEC requests from July 26, 2016 letter. GVEA and TPECI plan to complete a more thorough evaluation of groundwater flow characteristics prior to conducting further investigation. |
Janice Wiegers |
| 4/20/2017 |
Update or Other Action |
Email correspondence with TPECI discussing work for this summer; DEC requests monitoring plan with workplan for transducer study. |
Janice Wiegers |
| 9/12/2017 |
Update or Other Action |
Groundwater monitoring report submitted. Samples were collected on August 24, 2017. PCE and TCE were not detected in MW-7 and were below cleanup levels in MW-6 (reduced from 2016 monitoring event). PCE remains at 25.3 ug/L in the Zehnder well, but due to the November 2016 regulatory revisions, this no longer exceeds the cleanup levels. |
Janice Wiegers |
| 5/30/2018 |
Meeting or Teleconference Held |
DEC met with GVEA and TPECI to discuss site activities. GVEA is waiting for groundwater flow information from the Bentley Tax Lot 201 site, where SLR installed dataloggers around Noyes Slough. That information will be available next winter. Once the location of the dataloggers is available, TPECI will review that information and decide if additional data will be needed to represent groundwater flow directions associated with the Zehnder Well at this location. |
Janice Wiegers |
| 7/31/2018 |
Document, Report, or Work plan Review - other |
Annual Groundwater Sampling report submitted. MW-6, MW7, and the Zehnder well were sampled for VOCs on July 20th. No contaminants exceeded the DEC groundwater cleanup levels. PCE concentrations in the Zehnder well had decreased from 25.3 ug/L in 2017 to 21.6 ug/L. |
Janice Wiegers |
| 9/25/2020 |
Document, Report, or Work plan Review - other |
Travis/Peterson Environmental Consulting Inc. submitted a Groundwater Monitoring report, dated 9/16/2020. Groundwater samples were collected from MW-6, MW-7, and the Zehnder well. MW-6 was the only well containing contaminants above cleanup levels. TCE was present in MW-6 at 3.71 ug/L. The cleanup level is 2.8 ug/L. Other chlorinated compounds were detected in MW-6 below cleanup levels, including PCE, 1,2-dichloroethane, cis-1,2-dichloroehtylene, and trans-1,2-dichlorothylene. |
Janice Wiegers |
| 10/5/2021 |
Document, Report, or Work plan Review - other |
2021 groundwater monitoring report submitted. MW-6 is the only well currently be sampled. There were no exceedences in this well. |
Janice Wiegers |
