| Action Date |
Action |
Description |
DEC Staff |
| 8/20/2019 |
Update or Other Action |
Initial Sampling Effort- Personnel from the Hecla's Green Creek Mining Company (HGCMC) Environmental Department collected samples from the perimeter of the Concentrate Storage Building (CSB). These samples were analyzed by an in-house laboratory.
August 28, 2019 additional samples from the perimeter of the CSB were collected by Environmental Department personnel.
|
Jessica Hall |
| 9/3/2019 |
Update or Other Action |
A subset of the samples collected in August were sent to ACZ Laboratories for independent third-party analysis |
Jessica Hall |
| 10/8/2019 |
Update or Other Action |
Personnel from the HGCMC Surface Operations and Environmental Departments used hand shovels to remove material from around the perimeter of the CSB. Care was taken to remove only material believed to be recoverable concentrate (product) with minimal soils. A total of approximately 1.5 cubic yards of material was hand excavated and placed into two super-sacks. This material was subsequently run through the mill for metals recovery. |
Jessica Hall |
| 4/23/2020 |
Update or Other Action |
Personnel from the GC Surface Operations and Environmental Departments used a Vac-Truck to remove material from around the perimeter of the CSB. The objectives of this effort were to (1) remove residual product that was not recovered in October 2019 and (2) recover any product that may have escaped prior to sealing the CSB. Approximately 1.5 cubic yards of material was collected by the Vac- Truck. This material was subsequently run through the mill for metals recovery. |
Jessica Hall |
| 6/8/2020 |
Site Added to Database |
A new site has been added to the database |
Mitzi Read |
| 6/12/2020 |
Potentially Responsible Party/State Interest Letter |
Sent PRP Letter to Hecla Greens Creek Mining Company (HGCMC), ATTN Brian Erickson. |
Jessica Hall |
| 7/15/2020 |
Update or Other Action |
In their plan, October 28, 2019 HGCMC had proposed to remove the concentrate and impacted soils around the exterior of the CSB in two phases. Phase 1 would consist of concentrate recovery for reprocessing in the mill. Shovels would be used during phase 1 to prevent excessive removal of soil. During phase 2, any remaining concentrate and impacted soil would be excavated. It was estimated that the excavation would be approximately 2-3 feet around the perimeter of the CSB, to a depth of 12 to 18 inches. It was estimated this would generate about 35 cubic yards (CY) of residual concentrate and soil. All excavated material will be placed into covered containers and labeled appropriately. HGCMC’s plan to remove the concentrate and impacted soil was communicated to EPA and DEC last Fall. Copies of the emails and correspondence are in the electronic site file.
To date, HGCMC has recovered and reprocessed the concentrate described in phase 1. Prior to implementing phase 2, HGCMC planned to seal the CSB to minimize the future escapement of products from the CSB. This work was contracted to begin in April 2020. However, due to Covid-19 mitigation measures, the work was delayed. HGCMC hopes to complete the work as soon as the mitigation measures are lifted.
|
Jessica Hall |
| 8/28/2020 |
Update or Other Action |
HGCMC reported the CSB has been sealed to minimize the future escapement of products from the CSB. To date, HGCMC has recovered and reprocessed the concentrate described in phase 1. They are planning to proceed with phase 2 removal and disposal of remaining contaminated soils. This is approved by DEC. |
Jessica Hall |
| 9/26/2020 |
Update or Other Action |
Soil was excavated along the north side of the CSB. The excavation measured approximately 150 feet long by 4 feet wide and one foot deep. Large rocks were sorted by hand and left in the trench.
Approximately 30 CY of soil was placed in super-sacks. The super-sacks are being stored in sealed shipping containers pending waste characterization results. Four confirmation samples were taken from the excavation and sent to ACZ Laboratories for expedited analysis for lead and zinc.
|
Jessica Hall |
| 10/2/2020 |
Update or Other Action |
Soil was excavated along the northeast side of the CSB. The excavation measured approximately 50 feet long by 4 feet wide and one foot deep. Large rocks were sorted by hand and left in the trench. Approximately 9.0 cubic yards of soil was placed in super-sacks. The soil is being stored in a sealed shipping container pending waste characterization results. Three confirmation samples were taken from the excavation and sent to ACZ Laboratories for expedited analysis for lead and zinc.
|
Jessica Hall |
| 10/6/2020 |
Update or Other Action |
Soil was excavated along the southeast side of the CSB. Material in
this area is mostly rock. Approximately, 1.5 CY of soil was removed and stored in a shipping container. Two confirmation samples were taken from the excavation and sent to ACZ Laboratories for expedited analysis for lead and zinc.
|
Jessica Hall |
| 10/17/2020 |
Update or Other Action |
Based on the prior confirmation sampling, additional soil was
excavated along the eastern half of the north side of the CSB. Approximately 80 feet of the existing trench was dug a foot deeper. Large rocks were sorted by hand and left in the trench.
Approximately 15 CY of soil was placed in a lined, open top shipping container. Once filled, the liner was pulled over the material and a second container was placed on top as a lid, and the soils are being stored pending waste characterization results. Two confirmation samples were taken from the excavation and sent to ACZ Laboratories for expedited analysis for lead and zinc.
|
Jessica Hall |
| 10/23/2020 |
Update or Other Action |
HGCMC received analytical results from ACZ Laboratories. These results have guided HGCMC's decisions regarding the depth and volume of additional material to be excavated around the perimeter of the CSB. Based on the most recent analytical results received, HGCMC plans to excavate additional soil around the northeastern and southeastern perimeters of the CSB for remaining exceedances. The final excavation activities are scheduled for the spring of 2021.
|
Jessica Hall |
| 2/24/2021 |
Update or Other Action |
Based on the waste characterization results, the 55.5 CY (~62 tons) of excavated soils will be disposed off-site at a licensed disposal facility. Prior to disposal, appropriate manifests and shipping papers will be prepared. |
Jessica Hall |
| 4/27/2021 |
Update or Other Action |
Though some of the confirmation samples taken last year indicated elevated lead, the environmental technician taking those particular samples did not document the samples' location well. With the snow gone and the ground thawed, HGCMC has resampled the area to target the material for removal and minimize over-excavation. These samples were taken on April 27, 2021 and will be analyzed expeditiously. After the results are received, HGCMC will conduct targeted material removal, followed by confirmation sampling. |
Jessica Hall |
| 5/24/2021 |
Update or Other Action |
Per the Permitting and Environmental Compliance Coordinator
HGCMC, 1-2 CY of material were excavated from the area that the latest testing showed had residual contamination. A set of confirmation samples were collected and sent to ACZ Laboratory for analysis. Results are expected the results in 7-10 days.
|
Jessica Hall |
| 10/5/2021 |
Document, Report, or Work plan Review - other |
DEC sent comments to RP on Site Characterizations Report dated September 23, 2021. |
Jessica Hall |
| 11/3/2021 |
Exposure Tracking Model Ranking |
Initial ranking with ETM completed for source area id: 80600 name: Concentrate Storage Bldg |
Jessica Hall |
| 1/24/2022 |
Update or Other Action |
DEC requested an update re: when RP would submit an updated report for the previously reviewed Site Characterizations Report dated September 23, 2021. |
Jessica Hall |
| 3/22/2022 |
Document, Report, or Work plan Review - other |
Phone call with Hecla Greens Creek Mining Company. |
Jessica Hall |
| 4/12/2022 |
Update or Other Action |
Requested update on updated report submittal for Site Characterizations Report dated September 23, 2021. |
Jessica Hall |
| 6/7/2022 |
Site Characterization Report Approved |
The DEC approved the "HGCMC Concentrate Storage Building, Revised May 2022" report, dated May 25, 2022 and submitted to the department the same date. The report is approved with the understanding that because the 2020-2021 excavation and characterization work was completed without a DEC approved work plan, by an individual who did not meet DEC's independent Qualified Environmental Professional (QEP) qualifications, and analysis was performed by a lab that was not CSP approved, the data from this report is useable in the context of continued cleanup and delineation of the release but may not be appropriate for closure decisions. |
Flannery Ballard |
| 6/7/2022 |
Workplan Requested |
Additional removal of contaminated soil and site characterization are necessary at the site. The DEC has requested a site characterization work plan to be submitted to the department by July 15, 2022. |
Flannery Ballard |
| 6/20/2022 |
Site Visit |
The DEC undertook a site visit to the Hecla's Greens Creek Mining Company facility on 6/16/22 to inspect the Concentrate Storage Building. The foam sealant appeared to be in good shape and was intact along the the south, east, and north sides of the building. The west face of the building was sealed from the inside. Env Manager Marty Stearns was present. Division of Water performed inspection of Alaska Pollution Discharge Elimination System (APDES) permits. |
Flannery Ballard |
| 10/6/2022 |
Meeting or Teleconference Held |
DEC met in person with representatives of HGCMC to discuss site management. DEC outlined the cleanup and closure process and the need for horizontal and vertical delineation especially on the west side of the building. The EPA was also present via teleconference to answer applicable RCRA questions. HGCMC will re-submit a work plan to the DEC in the upcoming months. |
Flannery Ballard |
| 5/17/2023 |
Document, Report, or Work plan Review - other |
The DEC received the 2023 Sampling and Analysis plan for the HGCMC CSB on April 12. The DEC is providing comments which should be addressed before a revised version of the work plan is approved. The DEC is requesting additional information on stockpiling soils, field screening methods, and analytical methods. |
Flannery Ballard |
| 6/1/2023 |
Site Characterization Workplan Approved |
The DEC received a response to comments and an updated work plan, dated May 31. The work plan proposes field screening and test pitting activities to delineate lead and zinc contamination to the north, east, and south of the CSB, with characterization of the western side of the CSB where possible. Soil samples will be analyzed for total lead and total zinc, and a subsection of soils will be analyzed for TCLP. At this time, the DEC is satisfied with the long term monitoring activities in Hawk Inlet under management of the Division of Water. The issue of sediment sampling may be revisited in the future if findings indicate that human health, safety, or the environment are not adequately protected. In its work plan approval letter, the DEC made it clear that Hawk Inlet satisfies the definition of surface water under 18 AAC 75.990 (128), is a reasonable distance and downslope from the CSB, and has the potential to be impacted by the release at the CSB. The DEC will consider Hawk Inlet in the site's conceptual site model for migration and exposure routes. The work plan is too large to be uploaded to the database, but is available upon request. The DEC uploaded its work plan approval letter. |
Flannery Ballard |
| 3/26/2024 |
Document, Report, or Work plan Review - other |
Sent RP comments on the "Concentrate Storage Building Site Assessment Report" received on March 12, 2024. This report summarizes soil characterization work that took place in July and August 2023. A revised report was requested. |
Dawn Wilburn |
| 4/15/2024 |
Site Characterization Report Approved |
Reviewed and approved the revised Concentrate Storage Building Site Assessment Report dated April 1, 2024. In July and August 2023, test pits were mechanically or manually advanced along each outer wall of the building and soil samples were collected and analyzed for lead and zinc. Analytical soil samples contained lead concentrations (maximum 8,740 mg/kg) above the DEC Method 2 Over 40 Inch Zone Human Health (HH) soil cleanup level and zinc concentrations (maximum 18,300 mg/kg) above the Method 2 Migration to Groundwater (MTG) soil cleanup levels. Toxicity Characteristic Leaching Procedure (TCLP) lead results from samples collected for the southern and western walls exceeded Resource Conservation and Recovery Act (RCRA) limits for hazardous waste. Contamination was not delineated in several areas due to site structural interferences. Additional site characterization and cleanup was requested in the approval letter to the responsible party. |
Dawn Wilburn |
| 7/31/2024 |
Site Characterization Report Approved |
Reviewed and approved the Greens Creek Mine Port Facility Concentrate Storage Building Corrective Action Plan dated July 26, 2024. This work plan proposes further soil characterization investigation and remedial soil excavation actions. |
Dawn Wilburn |
