Referring to last year’s pipeline explosion in San Bruno, California, the Pipeline and Hazardous Materials Safety Administration (PHMSA) published an Advance Notice of Proposed Rulemaking (ANPRM) on August 25, 2011 for enhanced integrity management and other pipeline safety regulations for gas transmission pipelines. The ANPRM also addresses more comprehensive regulation of gas gathering lines and underground gas caverns. The ANPRM does not provide specific language for proposed rulemaking, but requests public comment on a range of topics related to current industry practices, the effects of enhanced regulations on safety and cost, and the best method to implement proposed regulations.
Many of the topics identified in the ANPRM are intended to address perceived regulatory gaps, including exemptions for grandfathered pipelines, operating pressure restrictions, and the application of regulations within and outside of High Consequence Areas (HCAs). It is likely that resulting regulations will broaden PHMSA’s oversight and impose significant changes on current integrity management practices of pipeline operators.
Modifying the Definition of HCA. PHMSA is considering expanding the definition of an HCA so that more miles of pipe are subject to integrity management requirements. As part of the ANPRM, PHMSA asks whether the existing HCA definition appropriately covers high risk areas and, if not, requests examples in which the definition is under- and over-inclusive. PHMSA also inquires whether expanding the definition of an HCA would increase burdens on operators given that non-HCA mileage is already subject to in-line inspection (ILI).
Implementation of Preventive Measures. PHMSA’s regulations require operators to take additional steps to prevent a pipeline failure and to mitigate the consequences of a failure within an HCA, but they do not require that a particular action be taken nor do they provide a standard for performing risk evaluations. In the ANPRM, PHMSA requests information on industry practices in assessing risk, action taken in response to risk assessments, and whether or not measures are applied categorically to pipeline segments within an HCA or if operators target measures for specific segments. PHMSA is considering a rulemaking that would impose preventive and mitigative requirements for HCA and non-HCA segments, including additional line-of-sight markers, close interval surveys for cathodic protection, depth of cover surveys, coating surveys or recoating, additional right-of-way patrols, shorter ILI run intervals, additional gas quality monitoring, and improvements in marking pipelines for operator construction and maintenance
Repair Criteria. The ANPRM identifies potential new rules related to repair criteria, including applying the integrity management repair criteria to non-HCAs; reassessing the repair criteria in areas that have become more populated since the pipeline was constructed; requiring methods to validate ILI tool performance and qualifications of personnel; and implementing risk tiering such that repairs in an HCA have priority over repairs in a non-HCA.
Improving Pipeline Data Collection/Validation and Risk Assessments. The PHMSA regulations currently require operators to collect data to assist in performing risk assessments. In the ANPRM, PHMSA notes that descriptive data on the ruptured pipeline segment in San Bruno contained errors and that analyses on risk could not yield accurate assessments. PHMSA requests information on industry practices in collecting and validating data, including excavation and in situ examinations of the pipeline as well as how models are used to manage risk. The ANPRM notes that PHMSA is considering making data collection and validation practice regulations more prescriptive; providing descriptive requirements for risk models or requiring the use of a particular risk model; mandating a maximum period in which pipeline risk assessments must be reviewed and validated as current and accurate; and mandating that operators more thoroughly integrate data from repairs into operational databases.
Improving Pipeline Assessment Methods and Corrosion Control. Existing integrity management regulations require operators to perform baseline and periodic assessments of pipeline segments in an HCA through one or a combination of in-line inspection, pressure testing, direct assessment of external and internal corrosion, or other technology demonstrated to accurately assess the condition of a pipe. PHMSA wants to know what anomalies have been detected using the various assessment methods. Potential rulemaking includes: requiring ILI assessment whenever possible and allowing for modification to transmission pipelines to accommodate ILI tools; establishing standards for direct assessment of internal corrosion (ICDA) and stress cracking (SCDA); and requiring a one-time pressure test for pipeline segments within an HCA to address construction and manufacturing defects.
Valve Spacing, Use of Valves Controlled Remotely or Automatically. The PHMSA regulations require that each point on a pipeline be located within a given distance of a block valve based upon class location. In the ANPRM, PHMSA asks whether the current block valve spacing is adequate as PHMSA is considering changing the maximum or minimum separation distances or using factors other than the pipeline’s class location in determining distances between block valves. While PHMSA’s predecessor concluded that remotely or automatically controlled block valves were not economically feasible, PHMSA is considering requiring all sectionalized block valves to be either remotely or automatically controlled.
Corrosion Control. PHMSA proposes to include criteria in the regulations that would require more rigorous corrosion control such as:
- requiring post-construction surveys for damage to or adequacy of protective coating;
- prescribing practices to address prevention, detection, assessment, and remediation of corrosion on transmission pipelines, including timing intervals for surveys;
- altering the definition of corrosive gas to reflect the corrosive properties of other constituents of a gas stream;
- requiring operators to conduct a corrosion threat analysis for every pipeline segment;
- requiring periodic analysis of operator corrosion management programs; and
- enhancing requirements for internal corrosion control for gathering pipelines.
Eliminating Exceptions for Pre-1971 Pipe. The pressure testing and manufacturing standards specified in PHMSA’s regulations apply to pipe manufactured since 1971. Pipe manufactured prior to 1971 is excepted from these requirements. In the ANPRM, PHMSA is considering removing this exception on the use of pipe manufactured prior to 1971 and requiring pressure testing for all pre-1971 pipe that has not already been tested to meet pipeline safety requirements. In addition, PHMSA expressed concern that the regulations do not currently include Quality Management Systems (QMS) or other quality assurances for the construction of pipeline, aside from the QMS requirements for pipelines intended to operate at an alternative Maximum Allowable Operating Pressure (MAOP). Potential rulemaking includes:
- repealing provisions that allow use of materials manufactured prior to 1971;
- requiring pressure testing for all pipelines or, in the alternative, pipelines known to have longitudinal welds susceptible to failure, not already pressure tested at or above 1.1 times MAOP; and
- establishing formal requirements for QMS in pipeline design and application to control equipment and materials in new construction as well as activities of contractors.
Underground Gas Storage. The ANPRM notes that underground storage caverns and injection/withdrawal piping are not regulated under PHMSA’s pipeline safety regulations, though pipelines that transport gas within a storage field are. Citing concerns that state regulatory oversight of underground storage facilities may not be sufficient, PHMSA proposes to develop federal safety standards for underground gas storage. Potential rulemaking includes:
- providing standards for welding, pressure testing, and design safety of casing and tubing;
- providing standards for internal and external corrosion monitoring;
- requiring emergency shutdowns on valves; and
- prescribing operation and maintenance procedures for periodic integrity assessments.
Modifying the Regulation of Gas Gathering Lines. In the ANPRM, PHMSA is proposing to expand its regulation of gas gathering lines. PHMSA expressed concern that the current regulatory oversight of gathering lines does not adequately cover current practices and allows gathering line operators to avoid necessary safety regulations. PHMSA is considering:
- amending regulations to require annual, incident, and safety-related conditions reports by operators of all gathering lines;
- expanding the definition for gathering lines used in the regulations to include pipelines downstream from processing or compression;
- establishing safety requirements for large-diameter, high-pressure gas gathering lines, including those located in rural locations; and
- adopting requirements for pipelines associated with landfill gas systems.
Responses to the questions posed in PHMSA’s ANPRM may be submitted using docket number PHMSA-2011-0023, and may be submitted electronically, by fax or by mail. The public comment period for the ANPRM ends on December 2, 2011.