| Action Date |
Action |
Description |
DEC Staff |
| 2/23/2006 |
Update or Other Action |
Frank Wessser of PERP sent a letter to the RP, Mr. Kingsbury, this date. The letter acknowledged department receipt of a spill report for this site, the department requirement of a cleanup, submission of reports to the department for review and approval, and the department's cost recovery policy. |
Frank Wesser |
| 2/27/2006 |
Interim Removal Action Approved |
Frank Wesser of PERP reviewed and verbally approved of the BGES, Inc. "Emergency Response, Heating Fuel Release, Talkeetna, Alaska", dated 2/27/06. |
Frank Wesser |
| 3/2/2006 |
Update or Other Action |
Interim removal action started 2/27/06 completed this date. Approximately 430 cubic yards of contaminated soil from the south side of the middle greenhouse was excavated. The excavation was approximately 27'W X 30'L X 27'D. In preparation for excavation, approximately 1/4 of the southern section of the middle greenhouse was dismantled. The excavated soils that were apparently "clean" were stockpiled adjacent to the excavation and later used as backfill. The apparently contaminated soils were placed in a bioremediation cell that was constructed to the south of the excavation.
A perforated horizontal pipe and riser pipes were placed in the excavation before backfilling. As a potential barrier to precipitation infiltration onto the contaminated soils, a 6 mil visqueen vapor barrier was placed in the base of the excavation over the drain tile pipe and through the riser. A second layer of visqueen was then placed in the excavation bottom. Another visqueen barrier was placed 2' below ground surface by the RP to act as an additional barrier to precipitation.
The excavation was backfilled with the apparently "clean" stockpile plus material from other surficial clean sources.
Lab samples collected from the sidewalls of the excavation indicated either non-detectable or below ADEC Cleanup Levels (in mg/kg GRO at 5.69, DRO at 27.5, and total xylenes to 0.2005). However, samples from the bottom of the excavation were above cleanup levels (in mg/kg 634 GRO, 3,890 DRO, 0.596 benzene, 6.65 toluene, and 9.57 ethylbenzene). The excavation bottom sample was also analyzed for PAHs. The only detectable PAHs were 1-methylnaphthalene at 7.08 mg/kg and naphthalene at 5.1 mg/kg. The former value is above the migration to groundwater cleanup level of 6.2 mg/kg but both of these detections were below the dermal/ingestion and outdoor inhalation cleanup levels. All biocell samples came back above cleanup levels. |
Frank Wesser |
| 4/13/2006 |
Spill Transferred from Prevention Preparedness and Response Program |
PERP Spill # 06239905301 from Frank Wesser. A memo was written this date by Frank Wesser indicating that the type of environmental impact that occurred at this site will require long-term site cleanup action. Consequently, the project is being transferred to the CSP. |
Bill Petrik |
| 5/3/2006 |
Site Added to Database |
Site added to the database. |
Bill Petrik |
| 5/3/2006 |
Site Ranked Using the AHRM |
Initial ranking. |
Bill Petrik |
| 5/5/2006 |
Update or Other Action |
File number issued: 2258.38.009. |
Aggie Blandford |
| 5/17/2006 |
Document, Report, or Work plan Review - other |
Reviewed BGES, Inc. report "Birch Creek Ranch; Talkeetna, Alaska; Interim Removal Action" dated April 2006. The report indicates analytical samples at 27', the bottom of the excavation, show GRO, DRO, benzene, toluene, and ethylbenzene in soil above Method 2 cleanup levels.
Talked to Mr. Kingsbury via telephone regarding site issues and the fact that I sent a letter out today to him that includes department requests for a workplan.
Sent a letter requesting workplan for annual sampling of water supply well; investigative borehole(s) to be drilled to determine aquifer in surficial deposits, GW elevations, GW flow direction, and sampling for GRO, DRO, and BTEX; bio-cell maintenance and remediation; and adherence and completion and return of a Cell Bioremediation Checklist. |
Bill Petrik |
| 6/7/2006 |
Update or Other Action |
Talked to Mr. Kingsbury today regarding his request for a department review and opinion of the BGES, Inc. workplan "Additional Soil Borings and Monitoring Well Installations, Emergency Response - Heating Fuel Release, Talkeetna, Alaska" dated 6/4/06 and Discovery Drilling workplan dated 5/25/06. Both workplans were on track to meet department requests except for minor additional conditons which included adding a CSM, field screening first borehole material to 25', clarify drilling and sampling needs, and dealing with soil and water IDW. |
Bill Petrik |
| 6/13/2006 |
Site Characterization Workplan Approved |
Reviewed a BGES, Inc. report Additional Borings and Monitoring Well Installations, Emergency Response – Heating Fuel Release, Talkeetna, Alaska dated June 4, 2006 and a Discovery Drilling Inc. letter dated May 25, 2006 and approved their related work plans with minor conditions for further investigation and characterization on the Birch Creek Ranch in the Talkeetna Area. Defining the extent of vertical migration of a diesel spill and if a ground water aquifer is present above bedrock are two major concerns of the work plans. |
Bill Petrik |
| 9/15/2006 |
Site Characterization Report Approved |
A letter to the RP was sent this date in response to work that was performed in accordance to a BGES, Inc. (BGES) work plan "Re: Additional Soil Borings and Well Installations, Emergency Response-Heating Fuel Release, Talkeetna, Alaska" dated June 4, 2006. The plan was approved by the CSP in a letter from the department dated June 13, 2006. A borehole was drilled to 42 feet below ground surface (bgs) in order to characterize the vertical extent of contamination. It hit bedrock at 42 feet bgs and was halted. No ground water was encountered. Soil samples were collected continuously from 4 feet bgs to the total depth of the boring and screened using a photoionization detector (PID) during drilling.
The vertical extent of the soil contamination was documented to have reached the boundary between the overlying surficial deposits and the more impermeable bedrock. The soil sample (SS-5) submitted for laboratory analysis was taken from 39 to 40.5 feet bgs. The result for DRO was 1,780 mg/kg, GRO was 556 mg/kg, benzene was non-detectable but the PQL was 0.565 mg/kg, toluene was 2.35 mg/kg, ethylbenzene was 6.09 mg/kg, and xylenes (total) were 34.4 mg/kg. The result values for DRO, GRO and ethylbenzene were above their respective migration to GW cleanup levels of 250 mg/kg, 300 mg/kg, and 5.5 mg/kg.
The lateral extent of the contamination beneath the excavated zone is unknown.
A potable private water supply well exists on the site. It is located approximately 177 feet west of the spill site. Although inconclusive, the well is thought to be down-gradient of the spill site. There is mention of a pond that seeps drain into. The pond is west of the site, making it down-gradient of the site. All results for the water supply well and the pond sampled on May 15, 2006 for DRO, GRO. and BTEX using Methods AK102 and SW8021B were below detection and cleanup levels under 18 AAC 75.345 Table C and Water Quality criteria in 18 AAC 70, respectively.
Annual sampling of the water supply well for DRO, GRO, BTEX, and VOCs using Methods AK101, AK102 and EPA 524.2; annual inspection of the seeps into the pond to observe for oily sheen emanating from the seeps; and a brief annual report of work performed regarding biocell activities that occurred during the year including an outline of work to be performed during the following year were requested.
A Conceptual Site Model was requested along with continued annual well sampling.
The CSP assigned a long-term monitoring (LTM) action in the CSP Database coincidental for the period that sampling will be conducted of the water supply well and observation for pond sheen.
|
Bill Petrik |
| 9/18/2006 |
Update or Other Action |
Talked with Mr. Kingsbury via telephone regarding the letter sent out Friday, 9/12, in response to the BGES, Inc. "Soil Boring Advancement" report dated July 2006. He had some questions regarding sampling and deadline dates. We also briefly discussed whether he could perform the sampling and I replied that it had to be done by a third party. |
Bill Petrik |
| 5/23/2007 |
Site Characterization Workplan Approved |
Reviewed and conditionally approved the revised BGES "Birch Creek Ranch 2007 Monitoring Work Plan" dated May 17, 2007. The work plan was to conduct annual water supply well sampling, annual inspection of seeps; annual bio-cell inspection and multi-increment sampling of it; laboratory analyses of soil and water samples for DRO, GRO, and BTEX adding VOCs for the water, updating the Conceptual Site Model including a narrative, and a report within 30 days. |
Bill Petrik |
| 11/16/2007 |
Site Characterization Report Approved |
The CSP received a copy of the BGES, Inc. "Birch Creek Ranch, Talkeetna, Alaska, Biocell and Water Monitoring Report" dated August 2007 via email on 8/8/07. The report was reviewed and approved and a related letter sent out on 11/16/07.
The drinking water well sampling results for GRO, DRO, and VOCs were all ND.
Biocell sampling result maximum values are 97 mg/kg GRO, 1,766 mg/kg DRO, ND (PQL 0.0919 mg/kg) benzene, and ND for toluene, ethylbenzene, and total xylenes.
No visual evidence of sheen was witnessed in the pond or seeps.
The CSP requested continued annual sampling of the biocell and drinking water well; continued annual inspection of the bluff seeps and pond to the west of the site; a work plan at least 60 days before the planned work; a Laboratory Data Review Checklist and updated Conceptual Site Model; and demonstration of qualified workers for the site and report. |
Bill Petrik |
| 4/14/2008 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed. |
Bill Petrik |
| 5/29/2009 |
Document, Report, or Work plan Review - other |
Reviewed the BGES, Inc. Birch Creek Ranch, Talkeetna, Alaska "Water Supply Monitoring Report" dated August 2008, received 9/2/08. On May 20, 2008 annual site monitoring was conducted that included inspecting the seeps and pond to the west of the property for evidence of sheen, inspecting the integrity of the biocell liner and cover, and collecting water samples from the drinking water supply well. The biocell liner was inspected and found to be in good condition. The water sample was analyzed for DRO, GRO, and VOCs. All analytical results were non-detectable and the MRL was below the cleanup levels. No visual evidence of sheen was witnessed in the pond or seeps to the west of the spill site during this event. A letter was sent this date from the CSP summarizing the CSP review of the report and requested continued monitoring activities in the summer of 2009. |
Bill Petrik |
| 4/8/2010 |
Document, Report, or Work plan Review - other |
Reviewed a copy of the BGES “Birch Creek Ranch Water Supply & Biocell Monitoring Report” dated December 2009 and received 1/20/10. Annual monitoring activities were conducted on 5/28/09 based on the 5/23/07 CSP-approved work plan. The activities included collecting water samples from the drinking water supply well, inspecting the seeps and pond to the west of the property for evidence of sheen, and collecting soil samples from the off-site biocell and inspecting its integrity.
A water sample was collected from the drinking water well at a point that was prior to any filtration associated with the water distribution system during the end of the peak seasonal water use that occurs each May and sent for laboratory analysis for DRO, GRO, and VOCs. All sampling results were ND.
The pond and seeps located west of the site were visually inspected for the potential presence of an oily sheen and none was observed in either.
Soil samples were collected from the biocell and its integrity inspected. The biocell was divided into three decision units (DU) and Multi-Incremental (MI) samples were taken from each of the units. A blind duplicate sample of the third DU was also taken. A required triplicate sample was inadvertently not collected during field sampling. The samples were laboratory analyzed for GRO, DRO, and BTEX. The BTEX sampling results for all biocell samples were ND. GRO and DRO were detected in all the samples. The GRO results ranged from 10.4 milligrams-per-kilogram (mg/kg) to 42.5 mg/kg, all below the 18 AAC 75.341 Method Two Migration to Groundwater cleanup level of 300 mg/kg. However, all samples were above the DRO cleanup level of 250 mg/kg, ranging from 461 mg/kg to 1,340 mg/kg.
For MI sampling triplicate samples are an integral part of the process because the three laboratory analytical sampling results are used to calculate the Relative Standard Deviation (RSD) of the triplicate samples and produce a statistically valid 95 percent Upper Confidence Limit (UCL) for the final MI sample result determination. In this case, only two MI samples were submitted and subsequently the proper calculations could not be made. Consequently, the highest of the two MI sampling results of each DU will be used as a general result for each DU. This does not change the fact that the biocell still remains above cleanup levels for DRO under this scenario. The CSP notes for future reference, however, that MI results that do not contain triplicate samples will not be considered for closure.
The biocell cover appeared to be in good condition except for a few small holes in it.
The CSP notes a decreasing trend in all the contaminant levels of the biocell as indicated in the table on page 10 of the subject report. Based on this table, that compares the results of 2006, 2007, and 2009 samplings, only DRO remains above cleanup levels in the biocell. The CSP requests continued work at the site based on the 5/23/07 CSP-approved work plan.
|
Bill Petrik |
| 4/13/2010 |
Exposure Tracking Model Ranking |
A new updated ranking with ETM has been completed for source area 75205 1,000 Gallon AST Release. |
Bill Petrik |
| 6/1/2010 |
Conceptual Site Model Submitted |
Received and reviewed a copy of the BGES, Inc. "Birch Creek Ranch Site Conceptual Site Model Update, Talkeetna, Alaska, ADEC File Number 2258.38.009, ADEC Hazard ID Number 4240" dated 5/28/10. |
Bill Petrik |
| 6/16/2010 |
Cleanup Complete Determination Issued |
A sample that was collected from the excavation bottom was the only one of the five that exhibited exceedances of the GRO, DRO, benzene, toluene, ethylbenzene, and 1-methylnaphthalene 18 AAC 75.341 Method Two Migration to Groundwater cleanup levels but below the dermal/ingestion and outdoor inhalation cleanup levels.
As of the last biocell sampling in May 2009 BTEX constituents are non-detectable (ND), the maximum value for GRO was 42.5 mg/kg which is below the Migration to Groundwater cleanup level, and the maximum value for DRO was 1,340 mg/kg. The DRO level remained above the Migration to Groundwater cleanup level but far below both the dermal contact/ingestion and outdoor inhalation cleanup levels of 10,250 mg/kg and 12,500 mg/kg.
A boring was drilled to bedrock at 42 feet bgs in May 2006. No groundwater was encountered. Analytical lab results from a soil sample taken from 39-40.5 feet bgs indicated that GRO, DRO, and benzene (based only on its practical quantitation limit) were above their respective Migration to Groundwater but below the dermal/ingestion and outdoor inhalation cleanup levels.
A drinking water supply well located approximately 177 feet from the spill area and approximately 186 feet from the biocell was sampled for DRO and VOCs in March 2006. The drinking water well was sampled for DRO and BTEX in May 2006 and for GRO, DRO, and VOCs in May of 2007, 2008, and 2009, and all the results were ND. Inspection of the pond and a seep on the property approximately 900 feet from the biocell/spill area and assumed down-gradient was performed each time the drinking water was analyzed and no sheen was observed as of the last sampling event.
Based on the latest Exposure Tracking Model (ETM) ranking, all pathways are either incomplete or de-minimis. Cleanup complete. |
Bill Petrik |
| 8/7/2015 |
Update or Other Action |
This file has been archived at Alaska Archives
Barcode 896981 Box 415 |
Susan Carberry |
