| Action Date |
Action |
Description |
DEC Staff |
| 12/4/1992 |
Update or Other Action |
COMR; PenAir had a release of 1,200 gallons from a fuel truck parked in Armstrong/PenAir's hangar. The fuel entered a drain pipe and was discharged outside the building below ground. |
Donald Seagren |
| 12/15/1992 |
Update or Other Action |
Letter received form PenAir following up on 4 December 92 spill report. PenAir has contracted Hart Crowser, Inc. to conduct a site assessment and cleanup. |
Eileen Olson |
| 12/30/1992 |
Update or Other Action |
Telephone call with Matt Zukowski, HC, to discuss site assessment and cleanup requirements. |
Eileen Olson |
| 5/5/1993 |
Update or Other Action |
Work plan for Site Characterization and Remedial Action received from Hart Crowser. |
Eileen Olson |
| 5/17/1993 |
Meeting or Teleconference Held |
Meeting with Hart Crowser, ADEC & EPA staff to discuss RCRA concerns related to site assessment & cleanup. |
Eileen Olson |
| 5/25/1993 |
Update or Other Action |
Work plan review comments sent to HC. Inc. |
Eileen Olson |
| 5/26/1993 |
Site Characterization Workplan Approved |
(Old R:Base Action Code = SA1R - Phase I SA Review (CS/LUST)). WDO sent a review letter approving the site characterization and remedial action plan, prepared by Hart Crowser and dated May 5, 1993, on the condition that re-sampling and analysis of the on-site water well is done before the end of June, 1993. Also requested were site-specific sampling procedures for water sampling and sample selection rationale for soil sampling. Work is expected to begin in June 1993. |
Former Staff |
| 5/26/1993 |
Update or Other Action |
Workplan addendum received to address ADEC concerns. |
Eileen Olson |
| 6/9/1993 |
Site Added to Database |
AvGas contamination. |
Former Staff |
| 8/5/1993 |
Update or Other Action |
Spill Assessment Report received. |
Eileen Olson |
| 10/21/1993 |
Site Characterization Report Approved |
(Old R:Base Action Code = SA1R - Phase I SA Review (CS/LUST)). WDO sent a letter approving the site characterization report prepared by Hart-Crowser dated 7/16/93, and requested that by 12/15/93:1)the vapor extraction remediation system recommended in the Hart-Crowser report or another acceptable remediation method be operational or complete and 2) that the on-site water well be resampled and analyzed. Note that during the site characterization work Hart-Crowser installed vapor extraction piping in anticipation of using that remediation method; therefore the deadline to begin remediation should not be onerous to PenAir. |
Former Staff |
| 9/6/1995 |
Site Ranked Using the AHRM |
Initial ranking. |
Bill Wright |
| 2/16/2005 |
Update or Other Action |
New staff assigned: Horwath. |
Sarah Cunningham |
| 4/1/2005 |
Update or Other Action |
Site re-ranked to clear up previous confusion related to this release and a LUST release adjacent to the hangar. |
Donald Seagren |
| 4/1/2005 |
Update or Other Action |
Sent letter to PenAir requesting project status update. |
Donald Seagren |
| 4/13/2005 |
Update or Other Action |
Scott Ruth, BEESC, will be the consultant for this site. They are searching the files to the 1 April 05 letter requesting a status update. |
Donald Seagren |
| 7/20/2005 |
GIS Position Updated |
Using Site Location Map in the Preliminary Environmental Assessment for Armstrong Air Services from Randolph Bayliss, P.E., in conjunction with TopoZone Pro, entered the coordinates for this site. Metadata include USGS Topo Map 1:63 AK Series, TopoZone Pro Street Map, Black and White Aerial Photo, on a Medium Size Map, View Scale 1:25,000 Coordinate Datum NAD83. Moderate degree of confidence in accuracy of location. |
Alyce Hughey |
| 12/16/2005 |
Update or Other Action |
sent e-mail to the consultant to see what he found in a search of the Penn Air files and what the plans are for achieving site closure in 06. |
Donald Seagren |
| 1/6/2006 |
Update or Other Action |
Discussed site with Scott Ruth, BEESC. Will develop a work plan for sampling on site DW well and on adjacent properties. Using a hand auger will bracket sample arond D1 & D7 from HC 93 report to determine current soil contamination. Not a high prioity - can wait until after breakup to conduct sampling. Once we know current conditions, we can determine best way to proceed to closure. |
Donald Seagren |
| 2/14/2006 |
Site Characterization Workplan Approved |
Reviewed and approved Site Assessment work plan. Work plan approval also coordinated with ADOT&PF. Work will be conducted during the summer of 06. |
Donald Seagren |
| 4/12/2007 |
Exposure Tracking Model Ranking |
|
Donald Seagren |
| 7/18/2007 |
Update or Other Action |
re-reviewed Pen Air report and compared with Area Wide GW Monitoring report. Dicussed & compared results with David Pearson. Discussed options for assessment/cleanup/monitoring. He will be discussing this with Shannon & Wilson and respond back with a proposal. |
Donald Seagren |
| 7/19/2007 |
Document, Report, or Work plan Review - other |
On this date, ADEC received Peninsula Airways, Inc. Dillingham, Alaska Site Assessment Report May 2007, submitted by Bristol. 16 soil borings were advanced in the gravel parking lot located northwest of the hangar. 20 soil samples including 2 duplicates were collected from 14 borings contained DRO up to 3,100 mg/kg , benzene up to 2.5 mg/kg and toluene up to 120 mg/kg. 5 GW samples including one duplicate were collected from B-01, B-03, B-04, and B-16. B-01 and B-03, collected from 10 ft. bgs., contained GRO up to 66.8 mg/L, DRO up to 51.8 mg/L, benzene up to 0.377 mg/L, and toluene up to 21.9 mg/kg. GW sample B-04, collected from an aquifer at 20 ft. bgs, contained contaminates, but below cleanup levels. |
Grant Lidren |
| 1/30/2008 |
Update or Other Action |
Received and reviewed the Area-Wide Groundwater Assessment ADOT&PF Dillingham Airport, dated June 2006, from Shannon & Wilson, Inc. During the area-wide groundwater assessment conducted at the ADOT&PF Dillingham Airport between May 23 and May 26, 2006, eleven soil borings were advanced and developed into eleven monitoring wells. The soil samples taken detected benzene at 0.0203 mg/kg from 0 to 5 feet below ground surface within the boring taken east of the Starflite, Inc. building. The groundwater samples taken detected DRO at 4.23 mg/L in the monitoring well located east of the Alaska Airline and PenAir building (former Armstrong Air), and GRO at 1.33 mg/L and Benzene at 0.189 mg/L in the monitoring well located west of the Lynden Air (Former Yute Air) building. Five drinking water wells were sampled, with Di(2-Ethylhexyl)phthalate at 4.4, ug/L, which is less than the drinking water standards and Di-n-Butylphthalate at 1.7 ug/L, for no drinking water standard has been established. This report is filed in the Soldotna office site file Armstrong Air, ADEC file number 2540.26.001. |
Alyce Hughey |
| 8/30/2010 |
Document, Report, or Work plan Review - other |
Three sets of nested monitoring wells will be installed and sampled to delineate the extent of impacts to groundwater at the site. |
Bill O'Connell |
| 10/12/2011 |
Document, Report, or Work plan Review - other |
Reviewed Monitoring Well Installation and Sampling Report for PenAir Hangar Dillingham. Three soil borings B17, B18, and B19 were advanced at the site and completed as monitoring wells in the shallow aquifer. A deeper well was also installed in borehole B18. The deeper wells planned for B17 and B19 could not be installed due to collapse of the boreholes. Soil samples collected from boreholes contained benzene at concentrations above ADEC cleanup levels with a maximum detected concentration of 0.0935 mg/kg at 5-7 feet bgs in borehole B17. Petroleum impacts were generally noted at two distinct intervals, 5-15 feet bgs and deeper than 25 feet bgs. This, along with borehole logs and static water level gauging indicates two water bearing zones are present that are separated by a less permeable silt layer. Groundwater samples collected from the shallower water bearing zone contained benzene up to 0.109 mg/l, GRO up to 52.2 mg/l, and DRO up to 31.4 mg/l. EDB was also detected above the cleanup level in the one sample in which it was analyzed at a concentration of 0.0058 mg/l. Soil and groundwater data indicate the greatest concentration of contaminants is near borehole B17, closest to the hangar building. In the deeper water bearing zone, benzene was detected up to 0.405 mg/l and DRO was detected up to 7.71 mg/l. Analytical data indicate DRO patterns from groundwater samples are consistent with weathered gasoline. There does not appear to be sufficient data to determine if contamination in the deeper zone is also attributable to the PenAir spill, however the excavation conducted in the area during spill response activities reportedly reached a depth of 19 feet bgs and the impacted soil that was excavated was reportedly used as backfill. |
Bill O'Connell |
| 1/18/2012 |
Meeting or Teleconference Held |
Meeting today with Penair and Shannon and Wilson to discuss 2012 activites including delineation of groundwater impacts, excavation and treatment of contaminated soil, and evaluation of the vapor intrusion pathway |
Bill O'Connell |
| 3/29/2013 |
Document, Report, or Work plan Review - other |
Reviewed PenAir Dillingham Corrective Action Plan. The objective of the corrective action is to remediate hydrocarbon contaminated soil adjacent to the PenAir hangar. In addition to the corrective action, the extent of the shallow groundwater plume will be delineated by installing up to 7 additional monitoring wells in the area and the vapor intrusion pathway will be evaluated through the use of the Johnson and Ettinger Model. Corrective action will include the excavation and landspreading of 600-700 cubic yards of contaminated soil at an offsite location. Excavation confirmation samples will be collected from the bottom and sidewalls of the excavation. If saturated, bottom samples will be collected from the lower sidewalls. Segregated overburden will be sampled for potential reuse as backfill. 8 soil samples will be collected from test pits at the land spreading location prior to spreading of the soil and confirmation samples will be collected from the spread soil after the second summer (2015). Groundwater samples will be collected from the newly installed wells following development. |
Bill O'Connell |
| 11/4/2014 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 72551 name: AVGAS release through floor drains |
Bill O'Connell |
| 7/2/2015 |
Cleanup Plan Approved |
Reviewed Corrective Action Plan (CAP) for PenAir Dillingham. Objectives of the CAP are to delineate the extent of groundwater contamination, evaluate the vapor intrusion pathway into the adjacent PenAir hangar building, and excavate and treat contaminated soil from the source area. Up to seven monitoring wells will be installed, developed, and sampled in an effort to delineate the extent of groundwater contamination in the shallow water bearing zone. A deeper water bearing zone is also present that appears to be contaminated from other sources at the airport. Soil samples will be collected from the boreholes at 2.5 foot intervals and one sample will be collected from each borehole. Approximately 600 cubic yards of contaminated soil will be excavated from the source area, transported to an offsite location, and land spread. The excavation will proceed no deeper than one foot into the saturated zone. Confirmation samples will be collected from the bottom and/or sidewalls of the excavation, depending on depth. Potentially clean overburden will be stockpiled separately and sampled to determine reuse. The land spreading location is on private property and will be graded and cleared prior to land spreading the soil in a 0.5 foot thick lift. Baseline soil samples will be collected from 8 shallow test pits after grading, prior to soil being spread at the site. Soil in each test pit will be field screened with a PID and one analytical sample will be collected from each test pit. The land spread area will not be lined, however berms will be constructed along the downgradient edges of the area to control runoff. After the soil is spread, the area will be divided into 60 segments, a sample will be collected from each segment and one analytical sample will be submitted for each 100 cy of soil based on field screening results. Post treatment sampling will be conducted in summer, 2017 to evaluate the efficacy of the treatment. |
Bill O'Connell |
| 12/23/2016 |
Update or Other Action |
Due to issues with the proposed landfarm location, excavation was not conducted in 2016 and instead will be conducted in Spring/Summer 2017. |
Bill O'Connell |
| 5/21/2018 |
Workplan Requested |
Sent PenAir a request for the Corrective Action Report, due by July 1, 2018. |
Erin Gleason |
| 7/12/2018 |
Update or Other Action |
Received email from Shannon and Wilson, the qualified environmental professional for PenAir. They conducted work in 2016 and are preparing a report. The report is due no later than November 1, 2018. |
Erin Gleason |
| 11/21/2022 |
Potentially Responsible Party/State Interest Letter |
Potentially Responsible Party letters sent to ADOT&PF, Alaska Airlines, and Tatonduk Outfitters Limited on this date. |
Naomi Mason |
| 1/24/2023 |
Potentially Responsible Party/State Interest Letter |
Potentially Responsible Party letters sent to Alaska Airlines Vice President of Real Estate and General Counsel sent on this date. |
Naomi Mason |
| 2/24/2023 |
Workplan Requested |
Work plan request letters sent to Alaska Airlines Environmental Program Affairs Manager, Alaska Airlines Vice President of Real Estate, and Alaska Airlines General Counsel sent on this date. |
Naomi Mason |
| 4/28/2023 |
Site Characterization Workplan Approved |
The revised Site Characterization Work Plan was received on 4/27/2023, ADEC has reviewed the work plan and it is now approved. Alaska Airlines' QEP, SLR, will attempt to sample the 11 groundwater monitoring wells on site. Groundwater samples will be analyzed for gasoline range organics (GRO), diesel range organics (DRO), petroleum volatile compounds (PVOCs), ethylene dibromide (EDB), and polynuclear aromatic hydrocarbons (PAHs). SLR also plans to collect vertical and horizontal distance data to get a better understanding of the hydrogeology at the site. Field work is expected to commence in late spring/early summer 2023. Alaska Airlines attempted to pursue the data collected in 2015, but could not locate a representative from the former PenAir corporation that could sign off on the transaction. |
Naomi Mason |
| 9/5/2023 |
Site Characterization Report Approved |
ADEC received the 2023 Site Characterization Report on 8/15/2023 and sent a letter approving the report on this date. Twelve groundwater monitoring wells (MWs) were presumed to be at the site, however, two could not be located and four were damaged beyond repair. The remaining six MWs were gauged and sampled. Only one could be surveyed. No free product was detected in any of the MWs sampled. Laboratory analytical results revealed concentrations of diesel range organics (DRO) above groundwater cleanup levels in two MWs (B17MW-S and PB20), B17MW-S also revealed residual range organics (RRO) and 1,2-dibromoethane (EDB) above cleanup levels. Concentrations of gasoline range organics (GRO) and various volatile organic compounds (VOCs) were detected below cleanup levels in multiple MWs. Only the shallow aquifer at the site could be investigated. Alaska Airlines will submit a workplan to resurvey the existing MWs, decommission damaged MWs, install additional MWs into both the shallow and deep aquifer. |
Naomi Mason |
