LMS/MND/S14085 Five-Year Review Report Fourth Five-Year Review for the Mound, Ohio, Site Miamisburg, Ohio September 2016 This page intentionally left blank LMS/MND/S14085 Five-Year Review Report Fourth Five-Year Review for the Mound, Ohio, Site Miamisburg, Ohio September 2016 Approved by: Date: ~ ~ '"-..._ ~ :~.< I I Susan Smiley Mound Site Manager U .S. Department of Energy Office of Legacy Management This page intentionally left blank Contents Abbreviations ................................................................................................................................ vii Executive Summary ....................................................................................................................... xi 1.0 Introduction ............................................................................................................................1 1.1 Purpose ........................................................................................................................1 1.2 Authority ......................................................................................................................1 1.3 Review Information .....................................................................................................2 1.4 Site Status ....................................................................................................................2 2.0 Site Chronology ......................................................................................................................5 3.0 Background ..........................................................................................................................11 3.1 Physical Characteristics .............................................................................................11 3.2 Land and Resource Use .............................................................................................11 3.3 Site History and Enforcement Activities ...................................................................14 3.3.1 History of Contamination ..........................................................................14 3.3.2 Enforcement and Agreements—Mound 2000 Process ..............................14 4.0 Remedial Actions .................................................................................................................17 4.1 Sitewide .....................................................................................................................17 4.1.1 Remedial Action Objectives ......................................................................17 4.1.2 Regulatory Actions ....................................................................................18 4.1.3 Remedy Selection ......................................................................................20 4.2 Institutional Controls .................................................................................................20 4.2.1 Remedy Selection ......................................................................................20 4.2.1.1 Maintain Industrial/Commercial Land Use and Prohibit Residential Land Use ................................................................21 4.2.1.2 Prohibit Use of Groundwater from Within the Site Boundary ............................................................................22 4.2.1.3 Prohibit Removal of Soil from Site to Offsite Locations ..........22 4.2.1.4 Prohibit Removal of Concrete from Floor in Specified Rooms of T Building .................................................................22 4.2.1.5 Prohibit Penetration of Concrete Floors in Specified Rooms of T Building .............................................................................22 4.2.1.6 Allow Site Access for Federal and State Agencies for Sampling and Monitoring .........................................................23 4.2.2 Remedy Implementation ............................................................................23 4.2.3 Operations and Maintenance ......................................................................23 4.3 Operable Unit 1 .........................................................................................................25 4.3.1 Remedy Selection ......................................................................................26 4.3.2 Remedy Implementation ............................................................................32 4.3.2.1 During OU-1 P&T System Operation .......................................32 4.3.2.2 During OU-1 EA Field Demonstration .....................................33 4.3.3 Operations and Maintenance ......................................................................34 4.4 Phase I Groundwater (MNA) Remedy ......................................................................34 4.4.1 Remedy Selection ......................................................................................34 4.4.2 Remedy Implementation ............................................................................35 4.4.3 Operations and Maintenance ......................................................................37 4.5 Parcels 6, 7, and 8 Groundwater (MNA) Remedy ....................................................37 4.5.1 Remedy Selection ......................................................................................38 U.S. Department of Energy Mound, Ohio, Fourth Five-Year Review September 2016 Doc. No. S14085 Page i 4.5.2 Remedy Implementation ............................................................................38 4.5.3 Operations and Maintenance ......................................................................42 4.6 O&M Costs for the Mound Site ................................................................................42 5.0 Progress Since Last Five-Year Review ................................................................................43 5.1 Institutional Controls .................................................................................................43 5.1.1 Protectiveness Statement from Last Review ..............................................43 5.1.2 Status of Recommendations from Last Review .........................................43 5.1.3 Status of Other Prior Issues .......................................................................43 5.2 Operable Unit 1 .........................................................................................................44 5.2.1 Protectiveness Statement from Last Review ..............................................44 5.2.2 Status of Recommendations from Last Review .........................................45 5.2.3 Status of Other Prior Issues .......................................................................45 5.3 Phase I Groundwater (MNA) Remedy ......................................................................45 5.3.1 Protectiveness Statement from Last Review ..............................................45 5.3.2 Status of Recommendations from Last Review .........................................45 5.3.3 Status of Other Prior Issues .......................................................................46 5.4 Parcels 6, 7, and 8 Groundwater (MNA) Remedy ....................................................46 5.4.1 Protectiveness Statement from Last Review ..............................................46 5.4.2 Status of Recommendations from Last Review .........................................46 5.4.3 Status of Other Prior Issues .......................................................................46 5.5 Operable Unit 4—Miami-Erie Canal ........................................................................46 6.0 FYR Process .........................................................................................................................47 6.1 Administrative Components ......................................................................................47 6.2 Community Notification and Involvement ................................................................47 6.3 Interviews, Surveys, and Record Reviews ................................................................47 6.4 Site Inspections ..........................................................................................................47 6.4.1 Annual Assessments of IC Effectiveness ..................................................47 6.4.1.1 2012 Annual IC Assessment .....................................................48 6.4.1.2 2013 Annual IC Assessment .....................................................48 6.4.1.3 2014 Annual IC Assessment .....................................................49 6.4.1.4 2015 Annual IC Assessment .....................................................49 6.4.1.5 2016 Annual IC Assessment .....................................................50 6.4.2 2016 FYR Inspections................................................................................51 6.4.2.1 Phase I and Parcels 6, 7, 8 Groundwater Monitoring Wells and Seeps ...................................................................................51 6.4.2.2 OU-1 Area and P&T System (Parcel 9) ....................................51 6.5 Documents Reviewed for FYR .................................................................................51 6.5.1 Basis for Response Action .........................................................................51 6.5.2 Operations and Maintenance ......................................................................53 6.5.3 Remedy Performance .................................................................................53