Overview
This is the second of a two-part brown bag Webinar series on the American Petroleum Institute’s new tool for estimating the LNAPL transmissity from bail-down test data using one or more of several analytical methods presented in literature. Today’s offering will provide examples using the Excel® spreadsheet, while the first offering, which took place February 27, 2013, gave insight into how the tool is used.
Bail-down tests are a simple method for estimating LNAPL transmissivity where a volume of LNAPL is rapidly removed from a well and the rate of fluid-level recovery (water and LNAPL) is measured and analyzed. Several methods are available to analyze the data from bail-down tests to estimate LNAPL transmissivity. To complement the new guide on LNAPL transmissivity published by ASTM (E2856-11), API released its spreadsheet tool, and supporting documentation.
The spreadsheet can be used to estimate the LNAPL transmissivity for unconfined, confined, and perched conditions using the gauging data. The spreadsheet tool does not automatically estimate the transmissivity from the gauging data but requires varying degrees of user consideration with regard to the gauging data and other input parameters. However, the spreadsheet is accompanied by a guidance document that provides additional details and examples to support the analysis of LNAPL transmissivity for various hydrogeological conditions.
Please note