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Timeline

A key component of any large remediation project is planning a realistic schedule that considers the numerous steps from design to completion and addresses the inter-dependencies of each activity. The remediation at the Orrington Site was divided into ten separate components and detailed schedules for each were prepared well in advance to ensure designs and work plans were submitted to DEP with enough time for appropriate review and discussions. Once the final design was agreed upon, requests for bids were sent out, contractors selected, and construction and restoration was completed in the appropriate season.

The timing and remediation of each area is described in detail under Project Clean Up and the map below shows each area. (Refer to the GWTP and Groundwater Project Clean Up pages for the timing of these activities.)

Removal Timeline Map January 2019.jpg

1994

Hanlin Group, Inc. sells the Site to Holtra-Chem Manufacturing Company L.L.C. and Holtra-Chem agrees to perform obligations under EPA Consent Agreement and Order from 1986.

1995-1998

CDM prepares Site Investigation Report and Revised Site Investigation Report for submission to the EPA and MEDEP.

2000

Holtra-Chem Manufacturing Company stops operations at the Orrington plant and shuts down site. Numerous Investigations and interim remedial actions are completed.

2001-2003

Numerous investigations are conducted by CDM to delineate the extent of soil and sediment impacts, characterize groundwater for treatability studies and evaluate soils for potential construction alternatives. Corrective Measures Study is submitted to the Maine DEP and the EPA. EPA and MEDEP issue Notice of Preliminary Media Protection Standards for the HoltraChem site.

2003-2015

The Cell Process Dismantling Work begins with the dismantling equipment within the cell building. Air monitoring around the building and at four other locations also begins. All buildings are cleaned, dismantled and completely removed from the Site by 2015.

2004

Interim Remedial Measures to extract groundwater from the base of Landfill #1 is approved by the MEDEP and CDM installs the system which begins pumping extracted groundwater in early 2005.

2010-2012

Mallinckrodt designed and constructed a new Groundwater Treatment System Plant (GWTP).

2014

On April 3, BEP issues an Order defining requirements to investigate and remediate contaminants at Orrington site.

2015

Significant pre-design work was completed to define soil, sediment, groundwater, and surface water conditions.

2016

Phase 7 final facility dismantling report was submitted. Landfill Ridge and Scrap Metal Yard remediation was completed, and the Landfill Ridge area restored. New caps were installed on Landfills 3, 4, and 5.

2017

Southern Cove, Northern Ditch, Southerly Stream remediation and Landfill 2 removal were completed. Scrap Metal Yard restoration was finished. Maine DEP approved the Landfill Ridge and Landfills 3,4,5 and Scrap Metal Yard Closure Reports.

2018

Remediation of Landfill 1 was completed. The Southerly Stream, Southern Cove, and Landfill 2 areas were restored to natural conditions. Maine DEP approved the Southern Cove, Northern Ditch, Southerly Stream, and Landfill 2 Closure Reports, and conditionally approved the Landfill 1 Closure Report. Maine DEP approved the Landfill 1 GWES Design.

2019

Plant Area Phase 1 remediation was completed. Cell Building remediation design submitted and approved by Maine DEP and began in late 2019. Landfill 1 GWES began operating.

2020

Plant Area Phase 1A remediation was completed. Cell Building remediation continued. Concrete and utility removal work began.

2021

Cell Building remediation and concrete and utility removal work continued. Maine DEP approved the Landfills 3-5 GWES Design, the system was constructed and began operating.

2022

Catch Basin #6/Paved Sump remediation design submitted and approved by Maine DEP and work began. Cell Building remediation and concrete and utility removal work continued.

2023-2024

Concrete and utility removal and Catch Basin #6/Paved Sump remediation work continued. Mallinckrodt and the Maine DEP continue discussions about the appropriate remaining steps needed to achieve closure of the Site.

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