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Enterprise Neptune Gas Plant

Parent Companies:
Enterprise Gas Processing L.L.C.
EPA Facility ID:
Other ID:
Facility DUNS:
Parent Company DUNS:


120 Trunkline Lane
Centerville, LA 70522
Lat / Long:
29.734, -91.434 (Get map)
GPS - Unspecified
Administrative Building
Horizonal accuracy:
50 m
Horizontal reference datum:
World Geodetic System of 1984
Source map scale:


Enterprise Products Operating LLC
(713) 880-6500
P. O. Box 4324
Houston, TX 77210 -4324
Foreign Address:

Person responsible for RMP implementation:

Douglas J. D'Aquila
Staff Engineer- Safety/PSM

Emergency contact:

Mitch Brignac
Plant Manager
(985) 855-4230
24-hour phone:
(337) 836-0014
Ext or PIN:

Other contacts:

Facility (or company) email:
Facility phone:
Facility (or company) URL:


Local Emergency Planning Committee:
St. Mary Parish LEPC
Full-Time Equivalent Employees:
Covered by OSHA PSM:
EPCRA section 302:
CAA Title Air Operating Permit:
CAA Permit ID#:
OSHA Star/Merit Ranking
Last Safety Inspection Date:
March 7, 2014
Inspecting Agency:
State environmental agency
Using Predictive Filing:


NGL Extraction
CBI claimed:
Program Level:
Natural Gas Liquid Extraction (211112)
Chemical name
Quantity (lbs.)
Flammable Mixture
Flammable Mixture
Flammable Mixture
Public OCA Chemical
Public OCA Chemical
Public OCA Chemical
Public OCA Chemical
Public OCA Chemical

RMP Preparer:


Foreign Address:


Latest RMP Submission:

June 23, 2014
5-year update (40 CFR 68.190(b)(1))


Effective Date:
Other Reason:

2. Toxics: Worst-case


3. Toxics: Alternative release


4. Flammables: Worst-case

Some Risk Management Plan information is not provided in the available RMP data. You need to make an appointment at an EPA Reading Room In order to get access to details from the Off-Site Consequence Analysis (OCA) such as:

Instructions on how to make an EPA appointment can be found here.

Public OCA Chemical (in NGL Extraction)
CBI claimed:
Model used:
Passive mitigation
  • None
not considered:
  • Blast walls

5. Flammables: Alternative release

Some Risk Management Plan information is not provided in the available RMP data. You need to make an appointment at an EPA Reading Room In order to get access to details from the Off-Site Consequence Analysis (OCA) such as:

Instructions on how to make an EPA appointment can be found here.

Public OCA Chemical (in NGL Extraction)
CBI claimed:
Model used:
Passive mitigation
  • None
not considered:
  • Dikes
  • Fire wall
  • Blast walls
  • Enclosures
Active mitigation
  • None
not considered:
  • Sprinkler systems
  • Deluge systems
  • Water curtain
  • Excess flow valve

6. Five-year accident history

Aug. 21, 2013 at 22:40
Natural Gas Liquid Extraction (211112)
1 minutes
Chemicals involved:
  • Flammable Mixture
Release events:
Gas release
Weather conditions at time of event
Wind speed:
3.0 miles/h
75.00 ℉
Atmospheric stability:
Precipitation present:
Unknown weather conditions:
On-site impacts
Deaths of employees or contractors:
Deaths of public responders:
Deaths of public:
Injuries of employees or contractors:
Injuries of public responders:
Injuries of public:
Property damage:
Known off-site impacts
Medicals treatments:
Property damage:
Environmental damage:
Initiating event:
Equipment Failure
Contributing factors:
  • Incorrect instrument reading; PSV relief below desired set pressure; water condensation in static vent line
Off-site responders notified:
No, not notified
Changes introduced as a result of the accident:
  • Improved/upgraded equipment
  • Revised operating procedures
  • Modify compressor control set points; repair and reset relief valve;

7. Prevention: Program level 3

NGL Extraction, Natural Gas Liquid Extraction (211112)
Prevention Program ID:
Safety Review Date
April 1, 2014, since latest RMP submission
PHA Update Date
June 18, 2013, since latest RMP submission
PHA Techniques
  • Checklist
Hazards Identified
  • Fire
  • Explosion
  • Overpressurization
  • Corrosion
  • Overfilling
  • Contamination
  • Equipment failure
  • Cooling loss
  • Floods
  • Hurricanes
Process Controls
  • Vents
  • Relief Valves
  • Check Valves
  • Scrubbers
  • Flares
  • Manual Shutoffs
  • Automatic Shutoffs
  • Interlocks
  • Alarms
  • Keyed Bypass
  • Emergency Air Supply
  • Emergency Power
  • Backup Pump
  • Grounding Equipment
  • Rupture Disks
  • Excess Flow Device
  • Purge System
Mitigation Systems
  • None
Monitoring Systems
  • None
Changes since PHA
  • None
Training Type
  • None
Competency Testing
  • Written Test
  • Oral Test
  • Demonstration
  • Observation
Procedure Review Date
Dec. 10, 2013, since latest RMP submission
Training Review Date
Oct. 9, 2013, since latest RMP submission
Maintenance Review Date
Oct. 9, 2013, since latest RMP submission
Maintenance Inspection Date
April 16, 2014, since latest RMP submission
Equipment Tested
Management of Change Most Recent Date
April 21, 2014
Management of Change Review Date
Oct. 9, 2013
Pre-startup Review Date
April 1, 2014
Compliance Audit Date
Oct. 9, 2013
Compliance Audit Change Completion Date
July 31, 2014
Incident Investigation Date
Aug. 22, 2013
Incident Invest. Change Completion Date
Dec. 31, 2014
Participation Plan Review Date
Oct. 9, 2013
Hot Work Review Date
April 9, 2014
Contractor Safety Review Date
Oct. 9, 2013, since latest RMP submission
Contractor Safety Eval. Date
April 1, 2014, since latest RMP submission

8. Prevention Program level 2

No Prevention Program level 2

9. Emergency response

Facility In Community Plan:
Facility Own Response Plan:
Specific Facility Response Plan:
Inform. Procedures in Response Plan:
Emergency Care in Response Plan:
Plan Review Date:
Response Training Date:
April 22, 2014
Local Response Agency:
Local Response Agency Phone:
(337) 836-5349
Subject To - OSHA EAP:
Subject To - CWA:
Subject To - RCRA:
Subject To - OPA:
Subject To - State EPCRA:
Subject To - Other:

Executive Summary

Neptune Gas Plant

Enterprise Products Operating LLC.

Executive Summary

Risk Management Plan

EPA Identifier: 1000 0017 2298

Accidental Release Prevention and Response

At Enterprise, we are committed to operating and maintaining all of our processes (especially those using hazardous substances) in a safe and responsible manner. We use a combination of accidental release prevention programs and emergency response planning programs to help ensure the safety of our employees and the public as well as protection of the environment. This document provides a brief overview of the comprehensive risk management activities that we have designed and implemented, including:

* A description of our facility and use of substances regulated by EPA's RMP regulation

* A summary of results from our assessment of the potential off site consequences from accidental chemical releases

* An overview of our accidental release prevention programs

* A five-year accident history for accidental releases of chemicals regulated by EPA's RMP rule

* An overview of our emergency response program

* An overview of planned improvements at the facility to help prevent accidental chemical releases from occurring and adversely affecting our employees, the public, and the environment

Description of the Stationary Source and Regulated Substances

The Enterprise Neptune Gas Plant is located in St. Mary Parish, Louisiana. The plant is owned by Enterprise Gas Processing LLC and operated by Enterprise Products Operating LLC.

The Neptune Gas Plant is a cryogenic turboexpander plant that extracts a mixed natural gas liquid product from an inlet stream of production natural gas. Inlet gas flows into the Neptune plant from a number of field gas gathering pipelines operated by Enterprise and other companies. The finished products, a mixed Y-Grade liquid product and residue gas, are transported from the facility via pipelines. The facility contains inlet gas compression and de
hydration, two process trains, residue gas compression, a propane refrigeration system and a heat recovery system that utilizes normal pentane as the energy recovery medium.

A pipeline drip stabilizer facility, operated by Neptune Plant, is located adjacent to the main cryogenic facility. The inlet gas compression and dehydration, and the drip stabilizer unit, including storage tanks, and truck racks, are handling naturally occurring hydrocarbon mixtures and are exempt from the RMP regulation.

The Enterprise Neptune Gas Plant was evaluated to determine if any regulated flammable or toxic substances exceeded the threshold quantity. Enterprise identified the regulated substances and quantities kept on site based on process knowledge.


No toxic materials to report.


Listed flammable substances that are stored above the threshold quantities at the Enterprise Neptune Gas Plant are natural gas liquids, natural gas, propane refrigerant and normal pentane. The Plant is subject to the Occupational Safety and Health Administration (OSHA) Process Safety Management (PSM) regulation and is classified as a Program Level 3 site under the EPA Risk Management Program.

Offsite Consequence Analysis Results

The offsite consequence analysis will not be reflected in the executive summary but rather is reflected in the data components. There are flammable substances on site and no toxic substances above the threshold quantity.

General Accident Release Prevention Program

The following is a summary of the accident prevention program in place at Neptune Gas Plant. The processes at the plant are regulated by the Environmental Protection Agency (EPA) Risk Management Program (RMP) regulation (Program 3), and are also subject to the OSHA's PSM Standard. This summary addresses each of the PSM program elements and describes the management system in place to implement the accident prevention program which is required only by the
facility OSHA PSM regulation coverage.

Employee Participation

Enterprise strongly promotes employee involvement in safety issues through existing programs. These programs include regularly scheduled safety meeting, tail-gate safety meetings, hazard communications, a "near-miss" reporting system and special training programs such as emergency response training, first aid training, etc.

Enterprise actively seeks employee involvement in the development and conduct of all accident prevention activities through the appropriate existing safety programs. Employees are encouraged to discuss accident prevention with their supervisors and to bring any questions, comments or suggestions forward for open discussion.

Process Safety Information

Enterprise keeps a variety of technical documents that are used to help maintain a safe operating process. These documents address chemical properties and associated hazards, limits for key process parameters, specific chemicals inventories and equipment design basis/configuration information. Chemical specific information, including exposure hazards and emergency response/ exposure treatment considerations is provided in material safety data sheets (SDS).

Enterprise also maintains numerous technical documents that provide information about the design and construction of process equipment. This information includes materials of construction, design pressure ratings, temperature ratings and electrical rating of equipment.

Process Hazard Analysis (PHA)

Enterprise primarily uses the hazard and operability (HAZOP) and Checklist method analysis technique to perform these evaluations. The analyses are conducted using a team of Enterprise staff which has operating and maintenance experience as well as engineering expertise. This team identifies and evaluates hazards of the process as well as accident prevention and mitigation measures, and the team makes recommendations for additional prevention and/or mitigation
measures when the team believes such measures are necessary.

The PHA team findings are forwarded to local and corporate management for resolution. Implementation of mitigation options in response to PHA findings is based on a relative risk ranking assigned by the PHA team. This ranking helps ensure that potential accident scenarios assigned the highest risk receive immediate attention. All approved mitigation options in response to PHA team findings are tracked until they are completed. The final resolution of each finding is documented and retained.

As part of Enterprise Process Hazard Analysis program, the facility will periodically update and revalidate the hazard analysis results.

Operating Procedures

Neptune Gas Plant maintains written procedures that address various modes of process operations such as; (1) start-up, (2) normal operations, (3) temporary operations, (4) emergency shutdown, (5) normal shutdown and (6) initial startup of a new process. These procedures provide guidance for experienced operators and also provide the basis for training new operators. Operating procedures include applicable safety precautions that must be taken in the operation of the facility. The procedures are periodically reviewed and annually certified as current and accurate. The review and certification process involves both operators and technical staff.


In addition to training on operating procedures, Neptune Gas Planthas a comprehensive training program for all employees involved in operating the process. New employees receive basic training in gas plant operations and safe work practices. All operators receive refresher training on the operating procedures at least every three years to ensure that their skills and knowledge are maintained at an acceptable level.


Neptune Gas Plant uses contractors during periods of increased maintenance or construction activities. Because some contractors work on or near process
equipment, the plant has procedures in place to ensure that contractors (1) perform their work in a safe manner, (2) have appropriate knowledge and skills, (3) are aware of the hazards of their workplace, (4) understand what they should do in the event of an emergency, (5) understand and follow site specific safety rules and (6) inform plant personnel of any hazards that they find while performing their work. This is accomplished by providing contractors with an orientation session that covers (1) a process overview, (2) information about the safety and health hazards, (3) emergency response plan requirements and (4) safe work practices prior to beginning their work. In addition, Enterprise evaluates contractor safety programs and performance during the contractor selection process. Enterprise personnel periodically monitor contractor performance to ensure that contractors are fulfilling their safety obligations.

Pre-Startup Safety Review (PSSR)

Neptune Gas Plant conducts a PSSR prior to the startup of all new facilities or any modification that requires a change in process safety information. The purpose of the PSSR is to ensure that safety features, procedures, personnel and equipment are appropriately prepared for startup prior to placing the equipment into service.

Mechanical Integrity

Neptune Gas Plant has well established practices and procedures for maintaining process equipment. The basic aspects of this program include (1) training, (2) developing written procedures, (3) performing inspections and tests, (4) correcting equipment deficiencies, when identified and (5) applying quality assurance measures. In combination, these activities form a system that maintains the mechanical integrity of the process.

Safe Work Practices

Neptune Gas Plant has safe work practices in place to help ensure worker and process safety. Examples of these include: (1) control of the entry/presence/exit of support personnel, (2) a lockout/tagout procedure
to ensure isolation of energy sources for equipment undergoing maintenance, (3) a procedure for safe removal of hazardous substances before process piping and equipment is opened, (4) a permit and procedure to control spark-producing activities (i.e. hot work) and (5) a permit and procedure to ensure that adequate precautions are in place before entry into a confined space. These procedures, along with training of affected personnel, form a system to help ensure that operations and maintenance activities are performed safely

Management of Change

Neptune Gas Plant uses Enterprise software-based change approval system to manage change to all covered processes. This system requires that changes to items such as process equipment, technology, procedures and other facility changes be properly reviewed and authorized before being implemented to ensure that the safety of the facility is not compromised by the change. Operating and maintenance personnel are provided any necessary training on any changes as part of the change management process.

Incident Investigation

Neptune Gas Plant promptly investigates all incidents that resulted in or reasonably could have resulted in, a fire/explosion, major property damage, environmental loss, or personal injury. The investigation team documents its findings, develops recommendation(s) to prevent a reoccurrence and forwards these results to the business management team for resolution.

Compliance Audits

To help ensure that the accident prevention program is functioning properly, Enterprise periodically conducts an audit of the program to determine whether the procedures and practices required by the accident prevention program are being implemented. Compliance audits are conducted at least every three years. Both hourly and staff personnel participate as audit team members. The audit team develops findings that are forwarded to operations or facility management for resolution. The final resolution of each fi
nding is documented, and the two most recent audit reports are retained.

Chemical Specific Prevention Steps

The processes at Neptune Gas Plant have hazards that must be managed to ensure continued safe operation. The following is a description of existing safety features applicable to prevention of accidental releases of regulated substances in the facility.

Universal Prevention Activities

The accident prevention program summarized previously is applied to all RMP covered processes at Neptune Gas Plant. Collectively, these prevention program activities help prevent potential accident scenarios that could be caused by equipment failures and human errors.

Specialized Safety Features

Neptune Gas Plant has safety features on many units to help contain/control a release, to quickly detect a release and reduce the consequence of a release. The following types of safety features are used in the covered processes:

Release Detection

* Hydrocarbon (hazardous gas) detectors and alarms

* Fire detectors on gas compression equipment

* Plant video surveillance system

Release Containment and Control

* Process relief valves that discharge to a flare to capture and incinerate episodic releases

* Valves to permit isolation of the process (manual or automated).

* Automatic shutdown systems for specific process parameters (e.g., high pressure).

* Secondary containment (curbs and dikes) to contain any release of liquid chemicals

* Redundant equipment and instrumentation where advisable

* Dual mechanical seals with seal failure alarms installed on hydrocarbon liquid pumps.

* Atmospheric relief devices

Release Mitigation

* Hand-held and wheeled cart fire extinguishers

* Personnel trained in emergency response and procedures.

* Personnel protective equipment (e.g., chemical protective clothing, hard hats, safety glasses, etc.)

Five Year Accident History

There was a release of gas from a broken relief valve discharge line in 2013.
There were no injuries or fatalities either on site or off site as a result of the release, and no environmental remediation required. Additional details on the incident are given in the registration 5-year Accident History section.

Emergency Procedures Information

Neptune Gas Plant maintains a written emergency procedure, which is in place to protect worker and public safety as well as the environment. The procedures are for the possibility of a fire or explosion if a flammable substance is accidentally released. The procedures address notification of local emergency response agencies if a release occurs. Employees receive training in emergency procedures. The emergency procedure is updated when necessary based on modifications made to the plant facilities.

The overall emergency procedure program for Neptune Gas Plant is coordinated with the Saint Mary Parish Emergency Management organization (LEPC). This coordination includes periodic meetings of the committee, which includes local emergency response officials, local government officials and industry representatives. Neptune Gas Plant has around-the-clock communications capability with appropriate LEPC officials and emergency response organizations (e.g., fire department). This provides a means of notifying the public of an incident, if necessary, as well as facilitating quick response to an incident.

Planned Changes to Improve Safety

Neptune Gas Plant resolves all findings from PHAs, some of which result in modifications to the process. Other recommendations for possible changes to improve safety come from periodic accident prevention program audits, incident investigations, or employee suggestions and recommendations. The following changes are planned for implementation at Neptune Gas Plant.

* Neptune Plant has recently replaced a three camera video monitoring system with a new multi-camera video security system.

* Enterprise is currently in the process of reviewing and r
evising the entire safety management / accident prevention program to ensure that the program can be fully administered across the diverse nature of the facilities owned or operated by the company.