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The LNAPL Resource Center contains manuals, software and other technical material to help you address cleanup of free-phase petroleum hydrocarbons in the shallow subsurface.

LNAPL Distribution and Recovery Model (LDRM)

API Publication 4760 May 28, 2008

API LDRM Version 1.2 addresses a units conversion error in Version 1.1 for the metric units output for skimmer well recovery rates.

The API LNAPL Distribution and Recovery Model (LDRM) simulates the performance of proven hydraulic technologies for recovering free-product petroleum liquid releases to groundwater. Model scenarios included in the LDRM are hydrocarbon liquid recovery using: single- and dual-pump well systems, skimmer wells, vacuum-enhanced well systems, and trenches. The LDRM provides information about LNAPL distribution in porous media and allows the user to estimate LNAPL recovery rates, volumes and times. View More

API Interactive LNAPL Guide Version 2.0.4

February 2006

The Guide is designed to provide an overall approach for evaluating LNAPL at a site to assess its potential risk, quantitatively defining mobility and recoverability, developing remedial strategies, and examining methods to enhance site closure. View More

Light Non-Aqueous Phase Liquid (LNAPL) Parameters Database Database and Guide for Data Retrieval

October 2006

This database is a collection of information about samples that have had their capillary parameters determined, as well as other physical parameters measured. Its purpose is to help users who are trying to characterize the movement and distribution of LNAPL within a site that has a limited set of direct observations. View More

Basic Baildown Testing Procedures to Measure LNAPL Transmissivity

A 14 minute training video about proper field procedures to facilitate successful performance of baildown testing to estimate LNAPL transmissivity