OUTLINE OF PROPOSED
LIGHT NON-AQUEOUS PHASE LIQUID (LNAPL) GUIDANCE
(January 31, 2006)
1.0 INTRODUCTION
1.1 Objective – To address LNAPL recovery for Act 2 and Act 32 sites and to provide a resource to evaluate LNAPL recovery to the extent practicable
1.2 Definitions - (e.g. direct evidence, indirect evidence, chemical composition, fluid properties, interfacial tensions, etc.)
1.3 Overview of LNAPL Saturation, Relative Permeability and LNAPL Recoverability Concepts
2.0 PERFORMANCE CRITERIA FOR THE EXTENT PRACTICABLE
· Readily recoverable LNAPLs are removed
· NAPL does not cause explosive conditions in surface or subsurface structures
· LNAPLs will not discharge to ground surface, surface waters, structures or additional groundwater aquifers
· Natural control (residual or stable LNAPL zone) or engineering controls prevent LNAPL zone expansion
· Groundwater MSCs are attained at Points of Compliance or Points of Exposure
3.0 Conditions for Mandatory Recovery OF lnapl
· LNAPL is within a wellhead protection zone in accordance with Clean Streams Law, Act of 1937.P.L. 1987, No. 394
· LNAPL is in contact with a current or identified future drinking water receptor in accordance with Clean Streams Law, Act of 1937.P.L. 1987, No. 394
· LNAPL is in contact with surface water in accordance with Clean Streams Law, Act of 1937.P.L. 1987, No. 394
· LNAPL is in contact with sediments in accordance with Clean Streams Law, Act of 1937.P.L. 1987, No. 394
· LNAPL is the source of a complete vapor intrusion pathway
4.0 SITE CHARACTERIZATION FOR LNAPL ASSESSMENT AND MANAGEMENT REQUIREMENTS
4.1 Development of Site Conceptual Model
4.2 Soil, LNAPL and Groundwater data collection for LNAPL assessment
5.0 DEVELOPMENT AND EVALUATION OF REMEDIAL ACTIONS
6.0 DEVELOPMENT OF MONITORING PLAN