2015 Groundwater and Surface Water Corrective Action Monitoring Plan
2015 Groundwater and Surface Water Corrective Action Monitoring Plan for the former ASARCO East Helena Facility, prepared March 2015. Download the PDF here.
2014 Supplemental Contaminant Source Area Investigation Report
2014 Supplemental Contaminant Source Area Investigation Report for the Former East Helena Smelter Site. Prepared February 2015.
Draft Interim Measures Work Plan
Now Available:
February 4, 2015 Former ASARCO East Helena Facility Draft Interim Measures Work Plan
East Valley Controlled Groundwater Area Petition – Supporting Information
Supporting Information for the East Valley Controlled Groundwater Area Petition – Lewis and Clark County, Montana
Prepared August 2014
Download the PDF here.
2014 Groundwater and Surface Water Corrective Action Monitoring Plan
2014 Groundwater and Surface Water Corrective Action Monitoring Plan for the former ASARCO East Helena Facility, Prepared July 2014. Download the PDF here.
Interim Measures Work Plan
Now Available:
May 16, 2014 Former ASARCO East Helena Facility Interim Measures Work Plan
Draft 2014 Interim Measures Work Plan
Now Available:
December 9, 2013 Draft 2014 Interim Measures Work Plan Former ASARCO East Helena Facility (11MB PDF)
Upper Lake Drawdown Technical Memorandum
The Montana Environmental Trust Group is conducting an Upper Lake drawdown test at the former ASARCO smelter site (the plant site) in East Helena, Montana. The purpose of this test is to simulate, at least partially, the effects of eliminating recharge from Upper lake on plant site groundwater levels, flow rates, and contaminant loading to groundwater.
For more information, download the Upper Lake Tech Memo (7MB PDF).
Final 2012 Interim Measures Work Plan
Former ASARCO East Helena Facility Interim Measures Work Plan—Overview of Proposed Interim Measures and Details of 2012 Activities.