| Action Date |
Action |
Description |
DEC Staff |
| 10/30/1991 |
Update or Other Action |
(Old R:Base Action Code = SA1R - Phase I SA Review (CS/LUST)). |
Former Staff |
| 12/6/1991 |
Update or Other Action |
(Old R:Base Action Code = TRET - Treatment, Selection). |
Former Staff |
| 3/26/1992 |
Update or Other Action |
(Old R:Base Action Code = RAPR - Remedial Action Plan Review (CS)). |
Former Staff |
| 3/26/1992 |
Update or Other Action |
(Old R:Base Action Code = SA1R - Phase I SA Review (CS/LUST)). |
Former Staff |
| 3/31/1992 |
Update or Other Action |
(Old R:Base Action Code = MS - Monitoring/Sampling). |
Former Staff |
| 4/14/1992 |
Update or Other Action |
(Old R:Base Action Code = SA2 - Phase II Site Assessment (General)). |
Former Staff |
| 5/2/1992 |
Update or Other Action |
(Old R:Base Action Code = SA2R - Phase II SA Review (CS)). |
Former Staff |
| 5/6/1992 |
Update or Other Action |
(Old R:Base Action Code = SA2 - Phase II Site Assessment (General)). |
Former Staff |
| 5/6/1992 |
Update or Other Action |
(Old R:Base Action Code = TRET - Treatment, Selection). |
Former Staff |
| 10/2/1992 |
Update or Other Action |
(Old R:Base Action Code = SA2 - Phase II Site Assessment (General)). |
Former Staff |
| 10/9/1992 |
Update or Other Action |
(Old R:Base Action Code = SA2R - Phase II SA Review (CS)). Response to SA2. |
Former Staff |
| 11/3/1992 |
Update or Other Action |
(Old R:Base Action Code = RAU - Remedial Actions Underway (General)). |
Former Staff |
| 11/20/1992 |
Update or Other Action |
(Old R:Base Action Code = RAPR - Remedial Action Plan Review (CS)). |
Former Staff |
| 5/6/1993 |
Site Added to Database |
Diesel contamination. |
Former Staff |
| 11/7/1994 |
Update or Other Action |
(Old R:Base Action Code = RAPR - Remedial Action Plan Review (CS)). No further cleanup or monitoring efforts are needed. GMW-2 should remain to provide future monitoring due to its proximity to the reported contamination recently discovered under the tank farm dike liner. |
Mike Krieber |
| 2/15/1995 |
Site Ranked Using the AHRM |
Site ranked earlier but no related action added to the database. |
Mike Krieber |
| 5/25/2001 |
Update or Other Action |
The monitoring data from GMW-2 indicated that there were no exceedances of contaminant levels in monitoring from 1991-1999. CVEA was issued a no further action determination based on this information. Site Closure Approved action rescinded 1/14/02 due to discovery of free product during MW abandonment. |
Jim Frechione |
| 8/27/2001 |
Update or Other Action |
CVEA provided notification in letter date 8/21/01, that all remaining monitoring, recovery and bioventing wells at the Valdez plant will be decommissioned by September 2001. |
Beatrice Egbejimba |
| 8/28/2001 |
Update or Other Action |
While attempting to abandon GMW-2, free-phase hydrocarbons was observed. All other wells were successfully abandoned. |
Beatrice Egbejimba |
| 12/17/2001 |
Update or Other Action |
ADEC received work plan from R&M Consultants to assess free-phase hydrocarbon observed in GMW-2. Report indicated three monitoring wells were installed. Soil samples collected showed no DRO present but groundwater samples collected from the three wells showed DRO as high as 78ppm present in GW. |
Beatrice Egbejimba |
| 1/14/2002 |
Update or Other Action |
Site Closure Approved action rescinded 8/28/01 due to discovery of free product during MW abandonment. |
Beatrice Egbejimba |
| 1/14/2002 |
Update or Other Action |
Letter sent to RP with request to investigate the source of DRO in GMW-2. |
Beatrice Egbejimba |
| 4/1/2003 |
Update or Other Action |
CVEA Glennallen conducted an investigation involving tap water sampling of their on site drinking water well and a free-phase hydrocarbon test. This investigation is associated with the hydrocarbon release observed during the decommissioning of a well last year. |
Beatrice Egbejimba |
| 4/9/2003 |
Update or Other Action |
ADEC sent letter to Steve Bushong with approval of Tap Water Sampling and Free Hydrocarbon Test report. ADEC agreed with Hart Crowser, Inc. recommendation to install additional monitoring wells. A work plan addressing this recommendation and other recommendations made in ADEC's January 14, 2002 letter must be submitted by July 5, 2003. |
Beatrice Egbejimba |
| 6/13/2003 |
Update or Other Action |
ADEC sent letter to Steve Bushong with approval of Free-Phase Hydrocarbons Remedial Investigation work plan. The plan proposed to evaluate the volume and extent of free-phase hydrocarbon present at the site. Off-site migration potential and remedial options will be explored. A site characterization report regarding this investigation should be submitted to ADEC by August 8, 2003. |
Beatrice Egbejimba |
| 4/7/2004 |
Update or Other Action |
ADEC sent letter to Steve Bushong with approval of Free Hydrocarbon Remedial Investigation report. Continued groundwater monitoring was requested. In addition, CVEA is requested to indicate the location of current (former tanks and any associate lines; any information relating to leak testing of the fuel lines by June 18, 2004. A maximum concentration of 4,260 mg/kg DRO was reported. Measurable free-phase hydrocarbon was observed in monitoring wells GRW-1, GRW-2, and MW-12 at a maximum thickness of 0.02 feet. |
Beatrice Egbejimba |
| 5/2/2005 |
Site Characterization Workplan Approved |
Workplan to bore three monitor wells in the powerplant building approved. The purpose of the release investigation is to determine the extent of free product at the site. Free product was observed during decommissioning of the monitor wells at the site. |
Eric Henry |
| 11/10/2005 |
Update or Other Action |
DEC completed review and approval of the work plan for installation of a free-phase hydrocarbon recovery system. |
David Pikul |
| 5/22/2006 |
Site Characterization Report Approved |
Product recovery pump installed in GMW-12 in November 2005. From November 2005 to June 2006, 33.7 gallons of product were recovered. Groundwater samples were collected from GMW-10,11,14,and 15. DRO above Table C in GMW-10,11, and 15. DRO concentrations decreased significantly in GMW-11 and GMW-14, however DRO increased in GMW-15 indicating potential contaminant migration off site to the south. |
Bill O'Connell |
| 8/8/2007 |
Site Characterization Report Approved |
Received June 2007 product and groundwater monitoring report. QA/QC conducted. Samples collected from GMW-10, 11, 13, 14, 15, and 16. No product recovered since Sept 2006, pump removed from GMW-12, however a sheen was noted on the surface of the water in the well. DRO above Table C in GMW-10, 11, 14, 15, and 16. Contaminant concentrations are generally stable. |
Bill O'Connell |
| 9/5/2007 |
Exposure Tracking Model Ranking |
Intitial Ranking Complete for Source Area: 72290 (Autogenerated Action) |
|
| 9/18/2008 |
Site Characterization Workplan Approved |
Received work plan for 2008 groundwater monitoring. Samples will be collected from well GMW-12 through GMW-16 and product levels will be gauged in recovery wells. |
Bill O'Connell |
| 10/31/2008 |
Document, Report, or Work plan Review - other |
The ADEC reviewed the Report for Glennallen Plant Groundwater Monitoring, dated October 29, 2008, submitted by Oasis, and received by ADEC on this date. Free product with a thickness of 0.05 feet was observed in GMW-12. Petroleum odor and sheen were noted in GMW-10 & GMW-12. All the monitoring wells with the exception of GMW-15 indicate DRO above ADEC cleanup levels. The highest levels of DRO in the ground water, analyzed in GMW-12, indicate a DRO level of 26.1 mg/L. Groundwater flow is to the south. |
Grant Lidren |
| 5/26/2009 |
Site Characterization Workplan Approved |
On this date, ADEC received the Work Plan for Regenox Injection and Groundwater Monitoring – 2009 CVEA Power Plant Glennallen, Alaska dated May 22, 2009 and submitted by Oasis. In early June 2009, Free-phase petroleum HCs will be measured in GMW-10 through GMW16. Wells which don’t contain measurable free product will be analyzed for DRO. Regenox will then be injected 15 times into a 11,000 ft. area underneath and just south of the CVEA Plant Building. In Fall 2009, the wells will again be measured for free product and analyzed for DRO. |
Grant Lidren |
| 9/2/2009 |
Document, Report, or Work plan Review - other |
On this date, ADEC received 2009 CVEA Power Plant RegenOx Injection and Spring Groundwater Monitoring Report Glennallen Alaska, submitted by Oasis dated August 28, 2009. On June 6, 2009, GMW-10 through GMW-16 was analyzed for DRO and an approximately 11,000 foot square area was injected with RegenOx. Due to difficulties of injecting the RegenOx in the subsurface only 1,900 lbs of RegenOx was used. No sub-slab injections, as prescribed in the work plan, occurred. No free phase products were measured in the monitoring wells and the GW elevations were 1.5 ft. lower than September 2008. Petroleum odor/sheen was noted in MW-12 and an odor was noted in MW-16. DRO was detected above ADEC cleanup levels in four monitoring wells ; 2.68 mg/L in GMW -11, 3.86 mg/L in GMW -12, 2.87 mg/L in GMW -14, and 2.22 mg/L in GMW -15. |
Grant Lidren |
| 12/4/2009 |
Document, Report, or Work plan Review - other |
ADEC received Fall 2009 Groundwater Sampling, CVEA Glennallen Plant, dated December 2, 2009, submitted by Oasis. Groundwater levels ranged from 8 to 13 ft. bgs, the mean of which was 1.2 feet lower than September 2008. GMW-10 through GMW-16 was analyzed. DRO was detected above ADEC cleanup levels in four monitoring wells: 5.23 mg/L in GMW -10; 2.13 mg/L in GMW -11; 19.3 mg/L in GMW -12; and 8.25 mg/L in GMW -16. |
Grant Lidren |
| 5/11/2010 |
Document, Report, or Work plan Review - other |
On this date, ADEC received and reviewed the Work Plan for CVEA Power Plant RegenOx™ Injection & Groundwater Monitoring 2010, submitted by Oasis, dated May 6, 2010. Monitoring well GMW-10 through GMW-16 will be analyzed for DRO in early June 2010. Two days following this groundwater monitoring event, 950 lbs. of RegenOx™ will be injected into the soil below the compacted silt layer located at 17.5 to 20 feet bgs , at 15 injection points, south of the CVEA Power Plant Building. Four to five of these injections will be located under the CVEA Power Plant Building. In the fall of 2010, a second DRO groundwater monitoring event for GMW-10 through GMW-16 will occur. |
Grant Lidren |
| 8/11/2010 |
Document, Report, or Work plan Review - other |
On this date, ADEC received the 2010 CVEA Power Plant RegenOx Injection and Spring Groundwater monitoring Report submitted by Oasis; dated August 11, 2010. Monitoring Wells GMW-10 to GMW-16 were analyzed. RegenOx™ was pumped into 7 injection points along a 11,000 square foot area along the south wall of the CVEA plant building. Unfortunately, due to tightly compacted silt soils, only half of the RegenOx™ (400 lbs.) was able to be injected into the ground. No free phase hydrocarbons were measured in the MWs. Purge water from GM-12 contained a hydrocarbon sheen and odor. Additionally, GM-12 was the only well to contain DRO concentration above ADEC clean up levels with DRO up to 5.95 mg/L. GW was 1.0 feet lower than the last sampling event in September 2009. |
Grant Lidren |
| 1/5/2011 |
Document, Report, or Work plan Review - other |
On this date, ADEC received CVEA Power Plant 2010 Fall Groundwater Monitoring Report, submitted by Oasis, dated January 4, 2011. Monitoring Wells GMW-10 to GMW-16 were analyzed.No measurable free product was encountered in any of the MWs. Purge water from GM-12 contained a hydrocarbon odor. DRO was detected above ADEC cleanup levels in four monitoring wells; 3.08 mg/L in GMW -10, 2.02 mg/L in GMW -11, 2.12 mg/L in GMW -12, and 4.37 mg/L in GMW -16. The results of Mann-Kendall and linear regression statistical analysis, w/ 90% confidence intervals, generally indicate a decreasing DRO trend in the GW. |
Grant Lidren |
| 5/13/2011 |
Document, Report, or Work plan Review - other |
On this date, ADEC received the 2011 Groundwater Monitoring Work Plan CVEA Power Plant submitted by Oasis, dated May 12, 2010. Groundwater in monitoring wells GMW-10 through GMW-16 will be analyzed for DRO in June and again in September. Additionally, during the September sampling event, monitoring wells GMW-10 thorough GMW-12 will be sampled for PAH. |
Grant Lidren |
| 2/14/2012 |
Site Characterization Report Approved |
On this date, ADEC received the 2011 CVEA Power Plant Groundwater Monitoring Report submitted by Oasis dated February 3, 2012. Groundwater in monitoring wells GMW-10 through GMW-16 were to be analyzed for DRO in June and again in September, but due to ice blockage or lack of water, MW-11 and MW-12 were not sampled during the June sampling event. Additionally, during the September sampling event, monitoring wells GMW-10 thorough GMW-12 were sampled for PAHs. During the June sampling event, only MW-16 contained DRO contamination above cleanup levels with DRO up to 4.64 mg/L and contained a “…light yellow-green color with a “chemical,” non-petroleum odor.” Groundwater was 14.58 to 16.25 feet bgs during June and 9.11 to 13.97 feet bgs during September. September sampling of monitoring wells MW-10, MW-11, MW-12, and MW-16 contained DRO above ADEC cleanup levels. The DRO in GW-16 contained significantly higher DRO concentrations at 63.20 mg/L. However the chromatogram for this sample contained large spikes and is not consistent with a diesel pattern. Reportedly, glycol spills have occurred at the site and the plug was missing from MW-16. It was noted that MW-16 contained a glycol odor and MW-10, MW-11, MW-12 contained a hydrocarbon odor. |
Grant Lidren |
| 6/28/2012 |
Risk Assessment Workplan Approved |
On this date, ADEC reviewed the Work Plan for 2012 GW Sampling & MW Decommissioning CVEA |
Grant Lidren |
| 12/3/2012 |
Site Characterization Report Approved |
On this date, ADEC received the Report for 2012 Groundwater Sampling and Well Decommissioning, CVEA submitted by Ahtna Engineering dated November 27, 2012. The four wells decommissioned include: MW-13, RW-1, RW-2, and RW-3. The measured GW elevation of 6.79 to 11.48 ft. bgs was 3.4 feet higher than in September 2011. A hydrocarbon odor was noted at MW-10. MW-12 contained an odor and sheen. MW-16 contained an greenish color and an ethylene glycol odor. All of the MWs sampled (MW-10, MW-11, MW-12, MW-14, MW-15 and MW-16) contained detectable levels of DRO. The DRO levels in mg/L were: 5.45 in MW-10, 5.96 in MW-11, 2.68 in MW-12, 1.11 in MW-14, 0.77 in MW-15 and 112in MW-16. The MW-16 DRO result is considered biased high due the presence of ethylene glycol in MW-16, which was measured up to 3,800 mg/L. |
Grant Lidren |
| 5/9/2013 |
Site Characterization Workplan Approved |
On this date, ADEC received the Work Plan for 2013 Groundwater Sampling CVEA submitted by Ahtna Engineering dated May 7, 2013. Groundwater samples will be collected from monitoring wells: 10, 11, 12, 14, 15, and 16; and analyzed for DRO and ethylene glycol. |
Grant Lidren |
| 11/13/2013 |
Site Characterization Report Approved |
On this date, ADEC received the Report for 2013 Groundwater Sampling, Copper Valley Electric Association Glennallen diesel Plant submitted by Ahtna and dated November 5, 2013. Groundwater samples were collected from monitoring wells: 10, 11, 12, 14, 15, and 16; and analyzed for DRO and ethylene glycol. Groundwater elevation was generally 2.2 feet lower than measured in September 2012. Monitoring well 12 contained a moderate hydrocarbon odor and sheen. Monitoring well 16 contained a greenish color with an ethylene glycol odor. All of the MWs sampled (MW-10, MW-11, MW-12, MW-14, MW-15 and MW-16) contained detectable levels of DRO. The DRO levels in mg/L were: 4.46 in MW-10, 3.58 in MW-11, 4.04 in MW-12, 0.82 in MW-14, 0.93 in MW-15 and 4.49 in MW-16. The MW-16 DRO result is considered biased high due the presence of ethylene glycol in MW-16, which was measured up to 2,200 mg/L. |
Grant Lidren |
| 7/7/2014 |
Site Characterization Workplan Approved |
On this date, ADEC received the Final Work Plan for 2014 Groundwater Sampling CVEA Glennallen Diesel Plant dated July 2, 2014. Groundwater samples will be collected from monitoring wells: 10, 11, 12, 14, 15, and 16; and analyzed for DRO. Monitoring Well MW-16 will also be analyzed for ethylene glycol. |
Grant Lidren |
| 11/12/2014 |
Site Characterization Report Approved |
On this date, ADEC received the Final 2014 Groundwater Sampling Report Copper Valley Electric Association Glennallen Diesel Plant submitted by Ahtna, dated November 12, 2014. In September 2013, groundwater samples were collected from monitoring wells: 10, 11, 12, 14, 15, and 16; and analyzed for DRO. Monitoring Well MW-16 was analyzed for ethylene glycol. Groundwater elevations were generally 3.9 feet higher than measured in September 2013. Monitoring well 12 contained a slight hydrocarbon odor and sheen. Monitoring well 16 contained a grayish-green color with a chemical smell, but no ethylene glycol odor as noted the past several years. Monitoring well 11 contained an pungent aromatic odor. All of the MWs sampled (MW-10, MW-11, MW-12, MW-14, MW-15 and MW-16) contained detectable levels of DRO. The DRO levels in mg/L were: 1.9 in MW-10, 22 in MW-11, 2.0 in MW-12, 1.2 in MW-14, 1.1 in MW-15 and 1.5 in MW-16. The MW-16 DRO result is considered biased high due the presence of ethylene glycol in MW-16, which was measured up to 91 mg/L. MW-11 was analyzed again in October 2014. The groundwater was 1 foot higher and the water contained DRO up to 36 mg/L. |
Grant Lidren |
| 5/20/2015 |
Document, Report, or Work plan Review - other |
Reviewed 2015 groundwater sampling work plan. Groundwater samples will be collected from monitoring wells: 10, 11, 12, 14, 15, and 16; and analyzed for DRO. Monitoring Well MW-16 will also be analyzed for ethylene glycol. |
Joshua Barsis |
| 12/3/2015 |
Document, Report, or Work plan Review - other |
Reviewed the Draft 2015 Groundwater Sampling Report, dated December 2, 2015 for the CVEA Glennallen Power Plant GW site. Five groundwater monitoring wells (GMW-10 through GMW-12 and GMW-14 through GMW-16) were sampled on September 15, 2015. All samples were submitted for analysis of DRO. The sample collected from GMW-16 was also submitted for analysis of ethylene glycol. Diesel range organics (DRO) was identified above ADEC groundwater cleanup levels in four of the six samples collected (from Wells GMW-10 through GMW-12, and GMW-16). The maximum detected concentration of DRO was 13 mg/L, which exceeds the ADEC groundwater cleanup level of 1.5 mg/L. Ethylene glycol was present in Sample GMW-16 (aptly named after the monitoring well where the sample was collected) up to 1,800 mg/L. The groundwater cleanup level for ethylene glycol is 73 mg/L. In a letter dated 12-4-2015, ADEC requested a work plan by February 1, 2016 for continued annual groundwater sampling at this site. |
Joshua Barsis |
| 2/16/2016 |
Document, Report, or Work plan Review - other |
Reviewed the Work Plan for 2016 Groundwater Sampling, dated February 11, 2016. Five groundwater monitoring wells (GMW-10 through GMW-12 and GMW-14 through GMW-16) will be gauged for static water levels depth and total depth, purged using low-flow techniques, sampled, and submitted for laboratory analysis of diesel range organics (DRO) and ethylene glycol. A report will be submitted by December 2016. ADEC approved this work plan via a letter in February 2016. |
Joshua Barsis |
| 12/12/2016 |
Document, Report, or Work plan Review - other |
Reviewed the draft 2016 Groundwater Sampling report, dated December 9, 2016. Six groundwater monitoring wells (GMW-10 through GMW-12 and GMW-14 through GMW-16) were gauged and sampled on September 15, 2015. All water samples were submitted for laboratory analysis of diesel range organics (DRO) and ethylene glycol.
Concentrations of DRO exceeded the Table C groundwater cleanup level of 1.5 mg/l in Wells GMW-10 (3.6 mg/l), GMW-11 (2.5 mg/l), GMW-12 (2.7 mg/l), and GMW-16 (3.0 mg/l). Ethylene glycol was not present above detection limits in any of the samples; however, these samples were analyzed outside of hold time and are considered estimated.
ADEC requested additional groundwater sampling for fall 2017. |
Joshua Barsis |
| 1/4/2017 |
Update or Other Action |
Received the final 2016 Groundwater Sampling report, dated December 15, 2016. |
Joshua Barsis |
| 5/2/2017 |
Document, Report, or Work plan Review - other |
Reviewed the draft Work Plan for 2017 Groundwater Sampling, dated April 24, 2017. Proposed activities mainly include collecting water samples from six groundwater monitoring wells (GMW-10 through GMW-12 and GMW-14 through GMW-16) for laboratory analysis of diesel range organics (DRO) and ethylene glycol. |
Joshua Barsis |
| 6/16/2017 |
Document, Report, or Work plan Review - other |
Reviewed the final revised Work Plan for 2017 Groundwater Sampling, dated June 12, 2017. |
Joshua Barsis |
| 11/27/2017 |
Document, Report, or Work plan Review - other |
Reviewed the 2017 Groundwater Sampling report, dated November 14, 2017. Six groundwater monitoring wells (GMW-10 through GMW-12 and GMW-14 through GMW-16) were sampled on September 7, 2017. All water samples were submitted for laboratory analysis of diesel range organics (DRO) and ethylene glycol. Concentrations of DRO exceeded the Table C groundwater cleanup level of 1.5 mg/l in Wells GMW-10 (1.65 mg/l), GMW-11 (1.93 mg/l), and GMW-12 (5.84 mg/l). |
Joshua Barsis |
| 5/10/2018 |
Document, Report, or Work plan Review - other |
Reviewed the draft Work Plan for 2018 Groundwater Sampling, dated May 10, 2018. Proposed activities include collecting water samples from five groundwater monitoring wells (GMW-10 through GMW-12, GMW-15, and GMW-16) for laboratory analysis of diesel range organics (DRO) only. ADEC approved this work plan in a letter dated May 10, 2018. |
Joshua Barsis |
| 11/26/2018 |
Document, Report, or Work plan Review - other |
Reviewed the 2018 Groundwater Sampling report, dated November 2018. Five groundwater monitoring wells (GMW-10 through GMW-12, and GMW-15 and GMW-16) were sampled on September 13, 2018. All water samples were submitted for laboratory analysis of diesel range organics (DRO). The sample collected from MW-16 was also submitted for laboratory analysis of ethylene glycol. Concentrations of DRO exceeded the Table C groundwater cleanup level of 1.5 mg/l in Wells GMW-10 (11.7 mg/l), GMW-11 (9.31 mg/l), GMW-12 (6.29 mg/l) and GMW-16 (2.93 mg/l). Ethylene glycol was not present in the sample collected from Well GMW-16. ADEC agrees with the report recommendations for continued monitoring of the same five wells and discontinuation of sampling for ethylene glycol. |
Joshua Barsis |
| 5/20/2019 |
Document, Report, or Work plan Review - other |
Reviewed the Work Plan for 2019 Groundwater Sampling, dated May 20, 2019. Proposed activities include collecting water samples from five groundwater monitoring wells (GMW-10 through GMW-12, GMW-15, and GMW-16) for laboratory analysis of diesel range organics (DRO) only. |
Joshua Barsis |
| 12/23/2019 |
Document, Report, or Work plan Review - other |
Reviewed the draft 2019 Groundwater Monitoring Report, dated December 2019. Water samples were collected from five groundwater monitoring wells (GMW-10 through GMW-12, GMW-15, and GMW-16) for laboratory analysis of diesel range organics (DRO) only. Except for Well GMW-16, all other wells exhibited levels of DRO above the Table C GCL of 1.5 mg/l.
ADEC agreed with the recommendation for further monitoring and additional remedial actions.
|
Joshua Barsis |
| 6/8/2020 |
Site Characterization Workplan Approved |
The Draft Work Plan for 2020 Groundwater Sampling Copper Valley Electric Association Glenallen Diesel Plant, received by the department on April 20, 2020, is approved. The workplan includes flush mount box repair on wells GMW-10 and GMW-11 and sampling for DRO at the wells GMW-10, GMW-11, GMW-12, GMW-15, and GMW-16. |
Lisa Krebs-Barsis |
| 2/9/2021 |
Document, Report, or Work plan Review - other |
Reviewed the 2020 groundwater monitoring report sent to the department on November 30, 2020. Repairs were made to GMW-10 and GMW-11. Water samples were collected from five groundwater monitoring wells (GMW-10 through GMW-12, GMW-15, and GMW-16) for laboratory analysis of diesel range organics (DRO) only. Except for Well GMW-15, all sampled wells exhibited levels of DRO above the Table C GCL of 1.5 mg/l. ADEC agreed with the recommendation for further monitoring. During this sample event GMW-16 exceeded cleanup levels (in 2019 it did not). GMW-15 was below cleanup levels but in 2019 was not. M-K analyses indicate increasing DRO levels in GMW-15. Monitoring wells GMW-10, GMW-11, and GMW-12 have no trend. GMW-16 was not included in trend analyses. |
Lisa Krebs-Barsis |
| 8/26/2021 |
Site Characterization Workplan Approved |
The department approved the work plan proposing sampling of GMWs 10, 11, 12, 15, and 16. The department had requested that CVEA survey the wells and calculate flow and gradient but CVEA did not budget for that. A survey has not been conducted since 2005 (at least) and reports described observed frost jacking and repairs to wells. Despite jacking and repairs the reports have been using the same elevation number to determine the elevation of groundwater since 2005. Previous reports of elevation may not be accurate. The 2021 report should include measured depth of wells and measure depth of groundwater from the top of the casing and historic information about the construction of those five monitoring wells. A survey should be included in the 2022 work plan. |
Lisa Krebs-Barsis |
| 4/29/2022 |
Site Characterization Report Approved |
The final report, received January 2022, was approved. Monitoring wells GMW-10, GMW-11, GMW-12, GMW-15, and GMW-16 were sampled. Evaluation of the monitoring well construction diagrams and current depth to the bottom of the well and depth to groundwater indicate that the water level was above the screened interval in all wells except GMW-10 during this sampling event. DRO in excess of cleanup levels was detected in GMW-10, GMW-11, GMW-12, and GMW-16. DRO was detected in GMW-15, downgradient well, below the cleanup level. Mann-Kendall analysis of data from the wells identified no trend for GMW-10 and GMW-11. An increasing trend was identified in GMW-12 and GMW-15. |
Lisa Krebs-Barsis |
| 5/9/2022 |
Document, Report, or Work plan Review - other |
The work plan submitted on 4-20-22 was reviewed and comments sent on 5-9. The comments requested that VOC sampling be conducted at GMW-12 to ensure a new release had not occurred. The comments specified that flow direction calculations and data be provided in the report and that the report include a ten year review of well depth and groundwater depth information. |
Lisa Krebs-Barsis |
| 11/3/2022 |
Update or Other Action |
CVEA sampled their drinking water well before the water treatment system. The sample was analyzed for DRO. An estimated 0.040 mg/L of DRO was detected in the water sample. |
Lisa Krebs-Barsis |
| 5/15/2023 |
Site Characterization Report Approved |
The 2022 Groundwater Monitoring Report describes work done in September 2022 which included surveying the wells and sampling of GMW-10, GMW-11, GMW-12, and GMW-15. Hydrocarbon odor was observed in GMW-10 and GMW-12 and an unrecoverable sheen was noted on GMW-10. All water samples were analyzed for DRO, samples from GMW-12 were also analyzed for VOC. DRO exceeded cleanup levels in all four wells sampled. The source area well, GMW-12 had a DRO concentration of 7.91 mg/L. Benzene, ethylbenzene, and naphthalene exceeded cleanup levels in GMW-12 at 0.0082 mg/L, 0.0337 mg/L, and 0.0538 mg/L, respectively. The most downgradient well sampled, GMW-15 at the southern property boundary, had exceedances of DRO at 1.84 mg/L. At most of the wells the water level was above the top of the casing. Well surevey results indicated the groundwater is flowing to the southwest. |
Lisa Krebs-Barsis |
| 5/16/2023 |
Document, Report, or Work plan Review - other |
Comments sent on the Draft Remediation Work Plan for 2023 PetroFix Injection. CVEA proposes injecting PetroFix into 24 injection wells directly upgradient of the property boundary well GMW-15 and monitoring the results over three years. DEC requested additional information and installation of a further downgradient well as contamination is not delineated and sampling at the new well and in GMW-15 for VOC and PAH along with DRO. DEC indicated that GMW-12 should also be sampled for PAH and VOC before injection. Sampling for PAH in GMW-12, 15, and the new well can occur once and if parameters are below cleanup levels, discontinued. Sampling for DRO and VOC must continue until the close of the site or concentrations consistently below the cleanup levels. |
Lisa Krebs-Barsis |
| 8/15/2023 |
Cleanup Plan Approved |
A work plan was approved to perform injections of Petrofix. A downgradient monitoring well will be installed and sampled.
Another sample of the upgradient drinking water well was not proposed but should occur in the future. |
Lisa Krebs-Barsis |
| 10/26/2023 |
Site Characterization Workplan Approved |
A work plan was approved to conduct groundwater monitoring at wells GMW12, GMW16, GMW11, GMW15, and GMW10. A sample from the drinking water well on site will also be collected. All samples will be analyzed for DRO. |
Lisa Krebs-Barsis |
| 3/14/2024 |
Document, Report, or Work plan Review - other |
The Draft 2023 Groundwater Monitoring Report was reviewed and comments sent. |
Lisa Krebs-Barsis |
| 3/26/2024 |
Site Characterization Report Approved |
The 2023 Groundwater Monitoring Report was approved. Groundwater monitoring was done on five monitoring wells (GMW-10, GMW-11, GMW-12, GMW15, and GMW-16) and the drinking water well. Samples were analyzed for DRO. Samples from all of the monitoring wells exceeded groundwater cleanup levels for DRO, ranging from 2.4 mg/L to 11.6 mg/L. A Mann-Kendall trend analysis was done on GMW-10, GMW-11, GMW-12, and GMW-15. No trend was observed for DRO in GMW-10 and GMW-11. An increasing trend for DRO is noted in wells GMW-12 and GMW-15 (most downgradient well). DRO was not detected in the drinking water sample. A survey of the monitoring wells indicated that groundwater is flowing to the south or southwest. Groundwater was above the screened interval in the monitoring wells sampled. |
Lisa Krebs-Barsis |
| 9/9/2024 |
Site Characterization Workplan Approved |
WORK PLAN APPROVAL: Final Work Plan for 2024 Groundwater Sampling, Copper Valley Electric Association, Glennallen Diesel Plant, Glennallen, Alaska (Ahtna, September 2024) |
Sophia Bracio |
