Dahej Nagothane Ethane Pipeline (DNEPL) Project Chapter-7 Additional Studies 7. ADDITIONAL STUDIES 7.1. Quantitative Risk Assessment Risk analysis study was conducted for DNEPL originating from RIL DMD in Gujarat to RIL NMD in Maharashtra with a spur pipeline to RIL HMD. Conducting a Quantitative Risk Assessment (QRA) is important in the management of risk, as cross country pipelines transport hazardous material traversing several hundreds of kilometres through villages, forests, rivers, roads, rail crossings, etc. Risk Assessment study was undertaken to address the hazards and risks associated with pipeline transportation of hydrocarbons as per requirement of MoEFCC. The goal of risk assessment is to estimate the risk to personal, property and public along the pipeline route from the unlikely event of leaks and/or rupture during pipeline operation. In addition, results of such studies provide help in improvement of safety by recommending measures to risk to the extent possible. This section outlines the Quantitative Risk Assessment (QRA) Report prepared by M/s Bureau Veritas. 7.1.1. Project Details The proposed pipeline will transfer liquid Ethane made available from RIL DMD to RIL NMD and HMD through 12” dia mainline and 8” dia spur pipeline respectively. One pump station is proposed to be located within RIL DMD. The pipeline will be constructed as per OISD 214 and ASME B 31.4 standards. Table 100: Salient details of the proposed pipeline Dahej Nagothane Ethane Pipeline Project–Salient Details Description UoM Details Design Throughput MMTPA 1.25 Pipeline Design Life (for Economic Years 30 Evaluation) Design pressure Bar(g) 112 Pressure at the Pipeline Inlet Battery Limit at DMD bar(g) 30(Min) Temperature at the Pipeline Inlet Battery Limit at oC 0 DMD DeliveryPressure bar(g) 56 (Min) DeliveryTemperature oC 30 (max) High integrity Three‐layer Type of External Anti‐corrosion Coating ‐ polyethylene (3 ‐LPE) Pipeline Design Code ‐ OISD ‐214, ASMEB31.4, Mainline Pump Station at Entry Point Location ‐ DMD, Gujarat Source: Provided by RGPL Cathodic protection system, Supervisory Control and Data Acquisition (SCADA) system, dedicated optical fibre cable based telecommunication system, mobile/permanent flaring Reliance Gas Pipelines Ltd. 255 Bhagavathi Ana Labs Pvt. Limited IND.BH.41.14.0029/HSR Rev. 03 Dahej Nagothane Ethane Pipeline (DNEPL) Project Chapter-7 Additional Studies systems at MLVs/IPSs, leak detection system / pipeline application software, emergency shutdown system, flow measurement and control instrumentation, fire and gas detection system, fire protection system, control and auxiliary buildings and associated facilities. 7.1.2. Need for Risk Assessment While underground pipelines have proven to be one of the easiest and safest ways to transport hydrocarbons, probability of loss of integrity/ damage exists due to interference from third parties, corrosion, accidents, human error etc. during normal operation cannot be overlooked. It is therefore necessary to evaluate the risk of pipeline operation to ensure safety to personnel, public, property and environment. 7.1.3. Objective of QRA Study The objective of the QRA study is to identify and assess the hazards associated with Dahej - Nagothane Ethane Pipeline Project in accordance with the following steps: • Identify accident events. • Determine the consequence of events; • Determine the frequency of hazardous releases from process piping, equipment etc. • Determine the risk to facility personnel and surrounding population from such releases; • Determine the risk to environment; • Determine the Residual Individual and Societal Risk. • Verify whether the assessed risks are acceptable on the basis of international risk criteria and, when needed, suggest risk reduction measures. • Final Report. The analysis is based on output from the DNV software modelling tool called PHAST Risk Micro v6.7. The outputs from PHAST Risk Micro in combination with Person in facility data is further analysed to determine Individual Risk (IR), and Societal Risk (SR). The inputs assumed for the modelling and the approach taken are detailed in the Assumption Register, attached as an Appendix A. 7.1.4. Scope of Work Quantitative Risk Analysis is undertaken to identify and assess the hazards associated with the project and to demonstrate that the residual risk levels are acceptable or As Low As Reasonably Practicable (ALARP). Scope includes also the following: • Identify key hazard initiating events associated with DNEPL Pipeline based on the Project document review; • Model and appraise the consequence & risk associated with all flammable hazards resulting from potential loss of containment accident scenarios; • Perform a risk assessment to confirm that risk can be reduced consistent with the ALARP principle and • Recommend risk reducing measures to ensure that all risks are As Low As Reasonably Practicable (ALARP). Risk Assessment studies have been done for 1.4 MMTPA for higher factor of safety. 7.1.5. Software QRA study has been performed using DNV PHAST Risk Micro v 6.7 software. Reliance Gas Pipelines Ltd. 256 Bhagavathi Ana Labs Pvt. Limited IND.BH.41.14.0029/HSR Rev. 03 Dahej Nagothane Ethane Pipeline (DNEPL) Project Chapter-7 Additional Studies Source and Battery Limit Liquid Ethane Source Liquid Ethane will be made available from RIL DMD. Composition and Properties Composition (mole %) of Ethane envisaged to be imported is as under: Liquid Ethane Composition Details Components Volume in Mole (%) Ethane 99.5 Methane 0.5 Source: Provided by RGPL Other vital properties of Ethane are listed below: Critical Pressure : 48.8bar Critical Temperature : 32.2ºC Design Throughput The pipeline shall be designed to transport 1.25 MMTPA of liquid Ethane considering the current and potential near future requirements. However, Risk Assessment studies have been done for 1.4 MMTPA for higher factor of safety. Battery Limit Conditions Following battery limit conditions have been considered: • Source Location – Storage Tank at DMD (at Pipeline Battery Limit) Pressure (Min) : 30 bar (g) Temperature (Max) : 0oC • Delivery Locations – At Pipe line Battery Limit) Pressure (Min) : 56 bar (g) Temperature (Max) : 30°C Climatic Conditions Preliminary temperature data along the route as collected from secondary sources are as follows: Maximum ambient air temperature : 50°C Ground temperature at pipeline depth : 20°C- 30°C Project Facilities Planning Project facilities forming part of the overall pipeline system comprising of trunk pipeline, originating pump station, mainline valve stations, intermediate pigging stations, and receipt terminal are described below: Reliance Gas Pipelines Ltd. 257 Bhagavathi Ana Labs Pvt. Limited IND.BH.41.14.0029/HSR Rev. 03 Dahej Nagothane Ethane Pipeline (DNEPL) Project Chapter-7 Additional Studies Preliminary locations of the project facilities proposed to be installed have been identified and shown in Overall Pipeline Schematic Arrangement Diagram attached at Exhibit ‐3 of Feasibility Report. These will be finalized during design and engineering phase. Facilities at Dispatch Pumping Station (PS at DMD) Mainline Pump Station shall be installed and set up at DMD, Gujarat which will broadly house following: • Inlet filtration system • Mainline Pumps with drives • Pig Launcher • Safety Instrumented System (SIS) • Fire and Gas (F&G) detection system and Fire Suppression System • Flaring facilities, Fire water, service water, plant air and instrument air distribution system • SCADA and Telecommunication system • Electrical facilities including Uninterrupted Power Supply (UPS), Battery Bank etc. • Buildings and HVAC system Maintenance bases will be set up at the Pumping Station at DMD and appropriate other location(s) along the route. Facilities at Intermediate Pigging Station (IPS) The broad list is given below: • Pigging facilities • Fire and Gas Detection System and Fire Suppression System • SCADA and Telecommunication equipment • Electrical facilities, UPS, Buildings and HVAC System • Mobile/Permanent Flaring System, Potable water facility, electric pump, water storage tank etc. Facilities at Delivery (M&R) Terminals The broad list for each station is given below: • Pigging facility • Filtration System • Custody Transfer Metering skid • Pressure / flow regulation and control skid • SCADA and telecommunication equipment • Fire and Gas Detection System, Fire Suppression System, Flaring facilities • BuildingsandHVAC system Facilities at Mainline Valve Stations Broad list of facilities at MLV station is given below: • Mainline valve with by ‐pass and mobile/permanent blow ‐down piping and flaring system Depending upon the type of MLV Station, following additional facilities will be provided: MLV Local Operation co-located with CP Facility • Solar powered supply with battery backup for CP equipment, area lighting, and guard room • Fire Extinguishers • BuildingtohouseCPequipment,batteriesandpowercontrollers Reliance Gas Pipelines Ltd. 258 Bhagavathi Ana Labs Pvt. Limited IND.BH.41.14.0029/HSR Rev. 03 Dahej Nagothane Ethane Pipeline (DNEPL) Project Chapter-7 Additional Studies MLV Remote Operation • Field instrumentation, SCADA and Telecom equipment • CP Equipment • Fire and Gas Detection System and Fire Suppression System • Control Building to house all equipment, battery etc. • Electrical facilities and emergency diesel engine generator back up. 7.1.6. Methodology The QRA methodology would include following steps. Source: Provided by BALPL Figure 79 : QRA Methodology 7.1.7. Consequence