American Petroleum Institute (API). Guidance Document. First Edition, October 2009. 44p. The purpose of this guidance document is to provide guidance and highlight industry recommended practices for well
construction and integrity for wells that will be hydraulically fractured. The guidance provided here will help to ensure that shallow groundwater aquifers and the environment will be protected, while also enabling economically viable development of oil and natural gas resources. This document is intended to apply equally to wells in either vertical, directional, or horizontal configurations.