4.1 This guide may be used in the investigation of underground storage tank systems for equipment problems in a wide variety of applications. Use of this guide is voluntary. It is intended to assist users who want to investigate equipment failures and malfunctions.

4.2 The following groups of users may find the guide particularly helpful:

4.2.1 Storage tank system designers;

4.2.2 Storage tank installers;

4.2.3 Storage tank maintenance contractors;

4.2.4 Storage tank removal contractors;

4.2.5 Storage tank inspectors;

4.2.6 Federal, state or local regulators, including departments of health, departments of environmental protection, and fire departments;

4.2.7 Storage tank release detection installers;

4.2.8 Storage tank testers;

4.2.9 Petroleum release remediation consultants;

4.2.10 Storage tank equipment manufacturers;

4.2.11 Insurance adjusters;

4.2.12  Storage tank owners and operators;

4.2.12.1 Retail fuel service station owners and operators;

4.2.12.2 Small businesses or enterprises;

4.2.12.3 Service industries;

4.2.12.4 Waste managers, including liquid and solid waste haulers, treatment, recycling, disposal and transfer;

4.2.12.5 Non-regulatory government agencies, such as the military;

4.2.12.6 Specific industrial sectors such as dry cleaners, printers, photo processors, laboratories; and

4.2.13 Consultants, auditors, inspectors, and compliance assistance personnel.

4.3 This guide is intended to assist in the development of protocols for the investigation of a malfunction or failure of storage tank systems and the implementation of said protocols. This guide outlines steps that may be necessary and include, but are not limited to initial evaluation of the UST system to determine the malfunction(s); preparation of samples of failed equipment for laboratory analysis; and document the investigation. The guide provides a series of investigation options on which the user may design failure investigation protocols. The guide describes common investigation techniques in the order in which they might be employed in an investigation.

4.4 A user may elect to utilize this guide for a number of reasons, which include, but are not limited to:

4.4.1 To differentiate new releases from new discovery of old releases;

4.4.2 To establish malfunction and failure rates of various storage tank equipment components;

4.4.3 To determine expected life spans of various storage tank equipment components;

4.4.4 To identify opportunities for improving the performance and reliability of storage tank equipment;

4.4.5 To focus inspection and maintenance efforts on those portions of the tank system that are most prone to malfunction and failure;

4.4.6 To identify those components of the storage tank system that require more frequent maintenance;

4.4.7 To reduce remediation and equipment replacement costs;

4.4.8 To prevent petroleum releases;

4.4.9 To identify those conditions that may cause or contribute to the deterioration or cause the malfunction and failure of various components of the UST system; and

4.4.10  To comply with environmental regulations that require the investigation of release detection alarms and the source of releases.

4.5 This guide may be used to establish a framework, which pulls together the common approaches to investigation. The framework will allow the user to establish an investigation protocol to meet their specific requirements. Specific user requirements will vary depending upon the purposes of the data collection and the decisions that the investigation is intended to support. This guide does not provide methods to establish specific user investigation requirements nor does it establish minimum levels of documentation.

4.6 This guide is not intended to require the user to conduct a failure investigation.

4.7 This guide is focused on the identification, documentation, and preservation of underground storage tank system equipment problems. It does not provide guidance on establishing root causes of malfunction or failure. The identification of root causes of malfunction or failure may require further expert analysis of the data and equipment collected during the failure investigation.

4.8 This guide does not address all the safety measures that must be taken when removing and disassembling underground storage tank systems. Because most underground storage tank systems have contained flammable or combustible liquids special precautions should be taken to prevent fire, explosions and exposure to toxic vapors. API standard STD 2015 and RP 2016 address some of the safety considerations as do many of the procedures available from fire departments.

1.1 Overview—This guide is an organized collection of information and series of options for industry, regulators, consultants and the public, intended to assist with the development of investigation protocols for underground storage tank facilities in the United States. While the guide does not recommend a specific course of action, it establishes an investigation framework, and it provides a series of techniques that may be employed to: identify equipment problems; in some cases prepare samples of failed equipment for laboratory analysis; and document the investigation. The guide includes information on methods of investigation, documentation, taking samples of problem equipment; preservation of equipment samples; chain of custody; storage; shipping; working with equipment manufacturers; and notification of regulators and listing laboratories. The goal in using the guide is to identify the appropriate level of investigation and to gather and preserve information in an organized manner, which could be used in the future to improve system design or performance. While this guide may act as a starting point for users with limited experience in failure investigation, the user is encouraged to consult with failure analysis experts for specific investigation procedures that may be needed for certain equipment and the investigation should be conducted by a qualified professional. As users develop their specific investigation protocols, they may find that the investigations can be streamlined for certain types of facilities.

1.2 Limitations of This Guide:

1.2.1 Given the variability of the different investigators that may wish to use this guide and the different types of facilities and failures that will be investigated, it is not possible to address all the relevant standards that might apply to a particular investigation. This guide uses generalized language and examples to guide the user. If it is not clear to the user how to apply standards to their specific circumstances, it is recommended that users seek assistance from qualified professionals.

1.2.2 This guide does not address safety issues associated with the investigation, taking samples and storing equipment. users are cautioned to exercise proper care in handling equipment that was in contact with flammable and combustible liquids and vapors. Some of the activities described in this guide may be subject to OSHA (Occupational Safety and Health Administration) regulations or may only be conducted by individuals with appropriate HAZWOPER (Hazardous Waste Operations and Emergency Response) training certifications recognized by federal and state regulatory authorities, such as HAZWOPER training.

1.2.3 This guide does not address laboratory investigations of material properties and detailed failure analysis.

1.2.4 This guide does not cover underground storage tank systems storing liquefied petroleum gas (LPG).

1.2.5 This guide does not replace state-required closure assessments and investigations. Requirements vary from state to state and often include specific sampling requirements.

1.3 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.