Site Report: ADOT&PF Cantwell Maintenance Station Class V Injection Well
| Site Name: | ADOT&PF Cantwell Maintenance Station Class V Injection Well |
|---|---|
| Address: | Milepost 135 Denali Highway, Cantwell, AK 99729 |
| File Number: | 190.38.006 |
| Hazard ID: | 26345 |
| Status: | Cleanup Complete |
| Staff: | No Longer Assigned, 9074655229 dec.icunit@alaska.gov |
| Latitude: | 63.389141 |
| Longitude: | -148.884484 |
| Horizontal Datum: | WGS84 |
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We make every effort to ensure the data presented here is accurate based on the best available information currently on file with DEC. It is therefore subject to change as new information becomes available. We recommend contacting the assigned project staff prior to making decisions based on this information.
Problems/Comments
In June, 2010 a Class V underground injection well at the Alaska Department of Transportation & Public Facilities Cantwell Old Maintenance Station (aka Cantwell Shop (old)) at Milepost 135 Denali Highway. Samples were analyzed for metals, volatile organic compounds (VOCs), and semi-volatile organic compounds (SVOCs). Samples were not analyzed for petroleum hydrocarbons. Due to data quality issues, sample results were unreliable and insufficient to determine if contaminants were present above DEC cleanup levels. Further investigation in 2016 indicated that of the two injection wells, CW-IW-1 (Old) does not present soil or groundwater contamination. The second IW, CW-IW-2 (New)resulted in impacts to subsurface and potentially water, requiring subsequent follow-up investigations. Only one source area will be further investigated associated with CW-IW-2.
Action Information
| Action Date | Action | Description | DEC Staff |
|---|---|---|---|
| 7/1/2014 | Update or Other Action | EPA Issues a 'Conditional Approval of Closure' for one injection well: CW-IW-1 (Old). Follow up investigation in 2016 identify no significant impacts at this location. | John Carnahan |
| 12/19/2014 | Spill Transferred from Prevention Preparedness and Response Program | Spill transferred by PERP staff Ashley Adamczak. Spill no. 12309933407; spill date = 11/29/12; substance = unknown; quantity = unknown; source = Class V injection well; PERP file no. 150.02.027. | Mitzi Read |
| 2/5/2015 | Site Added to Database | A new site has been added to the database | Mitzi Read |
| 8/4/2016 | Site Characterization Workplan Approved | EPA provides conditional approval for closure of one MVWDW at Cantwell site. | John Carnahan |
| 11/17/2016 | Meeting or Teleconference Held | Meeting with EPA and DOT to discuss status and CAFO requirements. | John Carnahan |
| 3/23/2017 | Document, Report, or Work plan Review - other | Receive final assessment report for two Cantwell injection wells. CW-IW-1 is not identified as having a significant release and recommendation for closure is requested. Low level concentrations of primarily petroleum-related contaminants were identified as associated with CW-IW-2 in soil and groundwater, recommending follow up assessment activities. | John Carnahan |
| 8/1/2017 | Meeting or Teleconference Held | Meeting with DOT and consultant to discuss upcoming proposed field work and work plans. | John Carnahan |
| 9/29/2017 | Update or Other Action | EPA provide a non-approval of reclassification of injection well from combined use to single use domestic. DOT will be required to close out the injection well system, including piping removal. | John Carnahan |
| 7/5/2018 | Update or Other Action | DOT to submit work plan for closure of injection well leach field to EPA during 2018 field season. DEC provides limited review comments. | John Carnahan |
| 7/19/2018 | Document, Report, or Work plan Review - other | EPA Approval of Closure Plan for One Motor Vehicle Waste Disposal Well at Alaska Department of Transportation and Public Facilities' Cantwell Maintenance Station, Northern Region, Alaska. | John Carnahan |
| 12/5/2019 | Meeting or Teleconference Held | Meeting held with ADOT and Shannon & Wilson to discuss 2019 sampling season and plans for 2020. | Michael Hooper |
| 10/28/2021 | Meeting or Teleconference Held | Annual meeting held with DOT Northern Region and contractors to discuss previous field season and plans for the next year. | Michael Hooper |
| 11/8/2021 | Workplan Requested | ADEC finished review of the well closure report. ADOT&PF requested a cleanup complete status. The site cannot be closed at this time due to a data gap identified in contamination delineation. An additional sample was requested west of the former CW-IW-2. | Michael Hooper |
| 11/17/2021 | Exposure Tracking Model Ranking | Initial ranking with ETM completed for source area id: 80103 name: Injection Well CW-IW-2 | Michael Hooper |
| 3/18/2022 | Site Characterization Workplan Approved | ADEC Approved a workplan addendum to collect soil and groundwater samples near the location of previous DRO exceedances. | Michael Hooper |
| 1/31/2023 | Cleanup Complete Determination Issued | ADEC has issued a cleanup complete determination for this site. DRO and Chloroform remain in soil in excess of the migration to groundwater cleanup levels, but groundwater has not been impacted. | Michael Hooper |
| 1/31/2023 | Institutional Control Record Removed | Institutional Controls have been removed. | Michael Hooper |
Contaminant Information
| Name | Level Description | Media | Comments |
|---|---|---|---|
| DRO | Between Method 2 Migration to Groundwater and Human Health/Ingestion/Inhalation | Soil | |
| Trichloromethane | Between Method 2 Migration to Groundwater and Human Health/Ingestion/Inhalation | Soil | Chloroform >MTGW in domestic wastewater leach field |
Control Type
| Type | Details |
|---|---|
| No ICs Required |
Requirements
| Description | Details |
|---|---|
| Advance approval required to transport soil or groundwater off-site. | |
| Movement or use of contaminated material (including on site) in a manner that results in a violation of the water quality standards is prohibited (18 AAC 70) |
| Hazard ID | Site Name | File Number |
|---|---|---|
| 22890 | ADOTPF - Cantwell Maintenance Station | 150.26.033 |