| Action Date |
Action |
Description |
DEC Staff |
| 10/23/2015 |
Meeting or Teleconference Held |
Contaminated Sites Program (CSP) staff met with Prevention, Preparedness and Response (PPR) staff, Habitat for Humanity, Alaska Aerofuel, HB Reuter Engineering, and Alaska Resources and Environmental Services (ARES) to discuss the workplan for additional mitigation and characterization efforts. Comments included the need for a thorough vapor intrusion study as well as groundwater delineation. ADEC recommended removing contaminated building materials when possible, rather than encapsulating them. |
Robert Burgess |
| 10/27/2015 |
Potentially Responsible Party/State Interest Letter |
Potentially responsible party / state interest letters sent to Alaska Aerofuel and landowner by PPR staff Patrik Sartz. |
Mitzi Read |
| 10/29/2015 |
Spill Transferred from Prevention Preparedness and Response Program |
Spill transferred by PPR staff Patrik Sartz. Spill no. 15309926401; spill date = 9/21/15; substance = diesel #1; quantity = 1,039 gallons; source = heating oil tank fill pipe. |
Mitzi Read |
| 10/29/2015 |
Site Visit |
Contaminated Sites staff visited the site with PPR project manager in preparation for transfer. Discussed spill and follow-up activities with Habitat for Humanity (building lessees) during and after a tour of the basement. Strong hydrocarbon odor was present in the basement and could be detected occasionally standing outside of the building. |
Robert Burgess |
| 11/3/2015 |
Site Added to Database |
A new site has been added to the database |
Mitzi Read |
| 11/4/2015 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 79835 name: #1 Diesel Release from Heating Oil Tank in Basement |
Mitzi Read |
| 11/30/2015 |
Document, Report, or Work plan Review - other |
DEC approved the revised Site Assessment and Contaminant Mitigation work plan. |
Robert Burgess |
| 12/30/2015 |
Site Visit |
Contaminated Sites project manager visited the site to observe ongoing work including the layout of sub-slab borings and the SVE system. Free product was found in several borings. In one boring, the free product appeared darker than the product detected in other borings. A sample from this boring was submitted for comparison to diesel heating oil. Building construction details including the depth of footers are unclear; additional investigation regarding the building construction is being pursued as it may affect contaminant migration. |
Robert Burgess |
| 1/5/2016 |
Meeting or Teleconference Held |
DEC met with Alaska Aerofuel, ARES, Habitat for Humanity, and Nortech to discuss ongoing issues at the site. DEC expressed the primary concern of protectiveness, including ensuring that adjacent buildings are not being exposed to diesel fumes through vapor intrusion and the need to limit contaminant migration, as well as the requirement to delineate contamination. ARES proposed to install a pump-and-treat type system designed to recover product and control hydrology to limit further contaminant migration. Unknowns include the construction and foundation depth of adjacent buildings which may affect contaminant migration as well as vapor intrusion. |
Robert Burgess |
| 1/6/2016 |
Site Visit |
DEC project manager visited the site and adjacent buildings with ARES in order to contact building owners, inform them of the potential for vapor intrusion, and ask for additional details on building construction to determine vapor intrusion potential and whether building basement walls or footers may act as barriers to groundwater and contaminant flow. |
Robert Burgess |
| 1/25/2016 |
Document, Report, or Work plan Review - other |
DEC received email update that two monitoring wells RW2 and RW3 were installed in the basement of the building and all four wells (RW1, RW2, RW3 and RW4) were developed. Purge water from RW1 had a thick oily sheen and fuel odor. Purge water from RW4 and RW4 had slight sheen and odor. Purge water from RW2 had no sheen and very slight fuel odor. |
Robert Burgess |
| 2/4/2016 |
Meeting or Teleconference Held |
DEC met with Alaska Aerofuel, Habitat for Humanity, and their contractors. Work to date and the current site status were summarized, including analytical results of soil, groundwater, and effluent air from the SVE system. The boiler has been removed from the basement and floor sealing is scheduled for February 8-12. Sampling ports will be installed on the SVE piping so that levels of hydrocarbons can be monitored. Indoor air samples will be taken the week of February 24, and further delineation of the plume outside the building will take place in late February and early March. A pump and treat system is still being designed and the goal is to install it before groundwater rises in the spring. |
Robert Burgess |
| 6/21/2016 |
Document, Report, or Work plan Review - other |
DEC received email update from ARES. As of 4/28/2016, no more free product was observed on the water table in any of the wells. |
Robert Burgess |
| 7/15/2016 |
Document, Report, or Work plan Review - other |
DEC received the Interim Corrective Action Report detailing the sampling and remedial activities conducted at the site through March 10, 2016. Actions included emergency cleanup of free product within the building, ventilation for air exchange, installation of a product recovery area beneath the source tank, installation of indoor product recovery and monitoring wells, active product recovery, collection of sub-slab gas data, installation of a soil vapor extraction system, soil sample collection during well and SVE system installation, collection of groundwater samples, removal of fuel and sealing of concrete floors and expansion joints, and sampling of indoor air to monitor vapor concentrations and effectiveness of these mitigation techniques. |
Robert Burgess |
| 3/17/2017 |
Document, Report, or Work plan Review - other |
DEC received the Groundwater Monitoring and Well Installation Report which documents the results of the release investigation conducted by ARES at the site. Three soil borings were advanced July 13 and 14 of 2016 to collect soil samples and then were developed into monitoring wells. Five soil and four water analytical samples were collected. Cleanup level exceedances were observed in soil samples from the boring closest to the source area (MW1) from 7 feet to 10.5 feet below ground surface. No cleanup level exceedances were observed in groundwater from MW1,however volatile and semi-volatile analytes were observed. No petroleum contaminants were observed in the soil samples collected from MW2 and MW3 which are the estimated upgradient and downgradient wells. DRO was detected in groundwater from these wells between the detection limit and the reporting limit. ARES recommends two additional groundwater monitoring events. |
Shawn Tisdell |
| 8/16/2017 |
Exposure Tracking Model Ranking |
A new updated ranking with ETM has been completed for source area 79835 #1 Diesel Release from Heating Oil Tank in Basement. |
Shawn Tisdell |
| 8/29/2017 |
Update or Other Action |
A groundwater sampling event was conducted in June. 0.18 ft of free product was measured in MW-1 (source area well). Naphthalene and 1-methylnaphthalene exceeded cleanup levels. DRO slightly exceeded cleanup levels in the down-gradient well RW4. A meeting will be coordinated to discuss these results and an appropriate path forward. |
Shawn Tisdell |
| 9/15/2017 |
Document, Report, or Work plan Review - other |
The DEC reviewed site reports and emails that documented cleanup activities at the site between September 2015 and June 2017. Comments and recommendations regarding these records were provided to the RP in a letter. Recommendations include an additional air sampling event in the winter to observe seasonal variation and additional groundwater sampling events to establish trends. |
Shawn Tisdell |
| 2/12/2018 |
Site Visit |
DEC staff observed cleanup activities associated with the heating oil spill at the site. The property owner and staff from ARES were present and participated in discussing progress and challenges regarding cleanup at the site. A parts per billion sensitive photoionization detector was used to screen indoor air at the site. Measurements throughout the building were approximately 100 ppb above outdoor air which is common in most buildings and does not suggest that the building is being impacted by vapor intrusion. The vapor mitigation system appears to be operating effectively at removing soil vapors from beneath the building. approximately 3/8" of free product was measured in monitoring well MW-1 which is located a few feet South of the location where much of the heating oil was released. An absorbent sock was used to recover this product from the well. |
Shawn Tisdell |
| 3/1/2018 |
Document, Report, or Work plan Review - other |
DEC received two reports dated 2/27/2018 which have been updated to reflect previous DEC comments. They are titled: "Groundwater Monitoring and Well Installation Report" and "Corrective Action Interim Report Remedial Actions, Vapor Extraction System Installation, Recovery Well Installation, and Analytical Sampling Report." |
Shawn Tisdell |
| 4/30/2018 |
Document, Report, or Work plan Review - other |
Indoor air sampling work plan received. |
Shawn Tisdell |
| 5/4/2018 |
Site Characterization Workplan Approved |
Seven indoor air samples and one outdoor sample will be collected over two weeks using passive diffusive samplers and analyzed for VOCs. |
Shawn Tisdell |
| 8/23/2018 |
Offsite Soil or Groundwater Disposal Approved |
DEC approval provided for disposal of contaminated groundwater monitoring purge water at OIT. |
Shawn Tisdell |
| 12/5/2019 |
Document, Report, or Work plan Review - other |
The ADEC has reviewed the October 4th, 2019, "Indoor Air Sampling Work Plan" for the site. This report presents a strategy for collecting indoor air samples after the active sub-slab depressurization system has been turned off to evaluate whether or not the depressurization system is still necessary to prevent soil vapors from entering the building and impacting indoor air. Some modifications have been requested to the report. These include sampling soil gas in addition to indoor air and sampling other gases to assess biodegradation potential. |
Shawn Tisdell |
| 1/28/2020 |
Site Characterization Workplan Approved |
Approval was provided by the DEC for the revised January 8, 2020 Indoor Air Sampling Work Plan. |
Shawn Tisdell |
| 2/5/2020 |
Site Visit |
DEC staff screened indoor air and observed deployment of passive air samplers in the building on 536 4th Avenue as approved in the work plan. A parts-per-billion (ppb) level photoionization detector was used to screen indoor air for volatile organic compounds (VOCs). Outside air measured 30 ppb and indoor air was 0 ppb throughout the building. A total of 9 samplers were prepared and deployed after the vapor mitigation system was shut down with the goal. Samplers will be retrieved after two weeks and submitted for analytical analysis. |
Shawn Tisdell |
| 3/5/2020 |
Update or Other Action |
DEC received preliminary results of a February 5-19, 2020 indoor air sampling event following the shut down of the vapor mitigation system. These results indicate that indoor air did not exceed residential target levels over the two week sampling interval. A report will be prepared to detail the sampling event. |
Shawn Tisdell |
| 6/1/2022 |
Meeting or Teleconference Held |
DEC talked with RP about current status of the building. The consultant is putting together a letter requesting closure as the indoor air vapor intrusion pathway is controlled by the vapor barrier installed in the basement and only one well has groundwater cleanup level exceedances. DEC staff indicated that they discuss the closure request and any potential data gaps to determine if additional sampling will be needed before a closure decision can be made. |
Shawn Tisdell |
| 11/6/2023 |
Site Characterization Report Approved |
DEC project manager reviewed the 2019-2022 Groundwater Monitoring report. This report reviewed groundwater sampling results from four sampling events of four wells to evaluate contaminant levels and trends. Diesel range organics (DRO) and naphthalene occasionally exceed DEC cleanup levels in MW-1 (immediately adjacent to the release location) and DRO has slightly increased at or above DEC cleanup levels in RW-4 (located within the building footprint downgradient from the initial release location). Additional groundwater monitoring is recommended during the Fall of 2023 when groundwater levels are high. |
Shawn Tisdell |
| 3/14/2024 |
Site Characterization Report Approved |
DEC project manager reviewed the 2023 Groundwater Monitoring report. This report reviewed groundwater sampling results from four wells to evaluate contaminant levels and trends. Diesel range organics (DRO) and naphthalene occasionally exceed DEC cleanup levels in MW-1 (immediately adjacent to the release location) and DRO increased above DEC cleanup levels in RW4 from 1.51 mg/L in 2017 to 12.7 mg/L in 2023. RW4 is located within the building footprint downgradient from the initial release location. Continued annual groundwater monitoring is recommended when groundwater levels are high. A request has been made to suspend gasoline range organic analysis for future sampling events since it has never exceeded ADEC groundwater cleanup levels in any well during historic sampling events. DEC concurs with these requests. |
Shawn Tisdell |
