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					                                SUMMARY REPORT
                    STUDY OF THE INTEGRITY MANAGEMENT
                        PRACTICES AND CONDITION OF
                            THE SAPREF TRANSFER
                       PIPELINES BETWEEN THE REFINERY
                                AND ISLAND VIEW.




                                REPORT No. PR0259




Client:        Ethekwini Municipality – Health Department
Attention:     Mr. Mervyn Chetty, Mr Neil Larratt, Mr Raj Hoolbhal
Address:       P O Box 2443
               Durban, 4000
Telephone:     031 300 3911




REV          DATE       PAGES        AUTHOR            REVIEWED      APPROVED
 0        7 Oct 2004      10     M.Sherratt (Pr Eng)   Dr C.Ringas   Dr C.Ringas
 1
 2




                                                                            DIN EN ISO 9001:2000
                                                                           Zertifikat: 01 100 040568
    Project No.: PP0220              Report No.: PR0259                     Revision No.: 0
     Summary Report: Study of the Integrity Management Practices and the condition of the
                 SAPREF transfer pipelines between the refinery and Island View.




  CLIENT                         :       Ethekwinin Municipality – Health
                                         Department
  CONTACT PERSON                 :       Mr. Mervyn Chetty, Mr Neil Larratt, Mr
                                         Raj Hoolbhal
  PROJECT                        :       Summary Report: Study of the Integrity
                                         Management Practices and the Condition of
                                         the SAPREF transfer pipelines between the
                                         Refinery and Island View.
  PROJECT NO                     :       PP0220


  REPORT NO                      :       PR0259


  REPORT:                        :       Martyn Sherratt (Pr Eng)        _____________


  REVIEWED BY                    :       Dr Chris Ringas                 _____________


  ORDER NO                       :       527094 OL


  DATE                           :       6 October 2004




  REPORT DISTRIBUTION:


Ethekwinin Health Department                   1    PPT HEAD OFFICE (MIDRAND)                 1
SAPREF                                         1




                                         Page 2 of 10
    Project No.: PP0220              Report No.: PR0259                     Revision No.: 0
     Summary Report: Study of the Integrity Management Practices and the condition of the
                 SAPREF transfer pipelines between the refinery and Island View.


                                             Table of Contents




1      BACKGROUND TO THE PROJECT................................................................. 4

2      CORROSION OF UNDERGROUND PIPELINES – BACKGROUND

       INFORMATION ................................................................................................ 4

3      PROJECT METHODOLOGY ............................................................................ 6

4      SUMMARY OF MAIN FINDINGS AND CAUSES OF LEAKS ........................... 7

5      RECOMMENDED PIPELINE INTEGRITY STRATEGY OPTIONS .................... 9




                                                  Page 3 of 10
    Project No.: PP0220              Report No.: PR0259                     Revision No.: 0
     Summary Report: Study of the Integrity Management Practices and the condition of the
                 SAPREF transfer pipelines between the refinery and Island View.


1        BACKGROUND TO THE PROJECT



Pipeline Performance Technologies (Pty) Ltd were appointed by Ethekwini Health
Department to undertake a detailed assessment of the historical and current
operating and integrity management practices being utilised by SAPREF and
ENGEN refineries. This project was initiated because of the fact that a number of
leaks have occurred on the SAPREF transfer pipelines since 1972. Given the health,
safety and environmental implications of product pipeline leaks PPT were appointed
to determine the cause of the leaks and make recommendations to implement
measures to prevent future leaks on the transfer pipelines. This report represents a
summary report, for the detailed technical report please refer to PR0219 Rev 1.


2        CORROSION OF UNDERGROUND PIPELINES – BACKGROUND
         INFORMATION


Steel pipelines have been used with much success for many years, in a diverse
range of industries to transport hazardous and non-hazardous materials. On modern
pipelines, the coating is regarded as the primary means of protection, with the
cathodic protection system providing secondary protection to the coating system at
defects in the coating. A properly manufactured and installed pipeline can provide
many decades of service. In addition, proper and regular maintenance of the coating
(by on-going repair of large coating defects) and monitoring of the CP system can
extend the life of the pipeline far beyond its original design life. Although many
pipelines have been designed for operational lifetimes of 25-30 years, it is not
common practice to replace these pipelines after this period. In fact, most steel
pipelines are in service indefinitely. A further advantage of steel pipelines is that they
can be inspected by a range of commonly used instrumentation, and suitable
refurbishment can then be undertaken, to extend the life of the pipelines even further.


Corrosion of metallic structures can shorten their useful life. Corrosion is an
electrochemical process, involving the movement of both electrons and ions. There
are a number of forms of corrosion, “rust” being one of the most recognised forms
and the one experienced by most people in their everyday lives. The forms of
corrosion that can affect buried pipelines are general corrosion (rust), localised
corrosion (where the corrosion is confined to small sections of the surface and the



                                         Page 4 of 10
 Project No.: PP0220              Report No.: PR0259                     Revision No.: 0
  Summary Report: Study of the Integrity Management Practices and the condition of the
               SAPREF transfer pipelines between the refinery and Island View.

rest of the metal surface is unaffected), microbiological corrosion (caused by bacteria
and other micro-organisms) and stray current corrosion (caused by DC electricity
from the electrified railway system). Whilst it is outside the scope of this report to
provide technical detail into the mechanisms of corrosion, the following factors are
involved in all corrosion processes:


      Anode (this is the part of the metal where the actual corrosion takes place)
      Cathode (this is a different part of the metal where reactions take place, but
       no corrosion occurs)
      Environment in contact with the metal (can be soil, water, etc)
      Electrolytic path (connecting the anode and cathode)
      All these factors have to be present simultaneously for corrosion to occur


The ways in which corrosion is reduced or avoided basically relies on removing one
of the above factors. So, in many cases, metallic structures are painted to separate
the corrosive environment from the metal surface. In other cases, the whole metal
surface is made cathodic and corrosion ceases. This latter method is called cathodic
protection and is commonly used on pipelines.


The corrosion protection of steel pipelines is therefore based on excluding the
corrosive environment from the metal surface, by applying a suitable coating, and,
because no coating is absolutely perfect, complimentary protection is provided by the
application of a so-called “cathodic protection “ system. The modern corrosion
protection package for pipelines is therefore primary protection by means of a coating
and secondary protection using cathodic protection. Cathodic protection is an
electrochemical technique which protects metallic structures in contact with an
electrolyte from corrosion. This is achieved by supplying electricity to the metal
structure and in this way the potential of the metal is changed. There are essentially
two ways in which this can be achieved. Firstly, use can be made of galvanic anodes,
such as zinc or magnesium, to provide sacrificial protection. This is typically what is
used to provide protection to ship hulls. Secondly, an impressed current system can
be used, by using an external DC source, such as a transformer rectifier (TRU), to
provide electricity to the metallic structure. The correct use of coatings and CP can
extend the life of pipelines by many years. It has become mandatory, in many
countries around the world, to provide CP to critical pipelines conveying hazardous




                                       Page 5 of 10
    Project No.: PP0220              Report No.: PR0259                     Revision No.: 0
     Summary Report: Study of the Integrity Management Practices and the condition of the
                  SAPREF transfer pipelines between the refinery and Island View.

substances. In South Africa, because of our stray current problem, it is common to
apply CP to all buried metallic pipelines.


3        PROJECT METHODOLOGY


The objective of the project was to review the historical and current operational,
integrity management and maintenance practices implemented by the refineries.
From a review of all available historical data (inspections, leaks, coating surveys,
corrosion surveys etc.) determine the cause of the leaks experienced by SAPREF,
and assess the condition of the transfer pipelines and associated risks of operating
under the existing conditions. Thereafter make recommendations on what needs to
be implemented to put in place a detailed Risk Based Assessment (RBA) and Risk
Based Inspection (RBI) Management system to prevent further leaks and operate
and manage the transfer pipelines in line with internationally accepted practice.


The detailed investigation of the SAPREF transfer lines included an in-depth
documentation review of the following:


        International studies on failures of pipelines with resultant causes,
        The SAPREF transfer lines leak history,
        External coatings and coating integrity surveys,
        The cathodic protection system and associated studies,
        Inspection using in-line inspection techniques (intelligent pigging),
        Tightness and hydrostatic testing,
        SAPREF’s risk based assessment plan (Management of Transfer Lines),
        Review of proposed refurbishment strategies,
        Right of way issues,


In addition to the documentation review, PPT was involved in the following activities:


        Site visits along the transfer pipeline route, visiting existing repair sites etc.
        Meetings with SAPREF operational & maintenance staff.
        Based on historical surveys and inspections (intelligent pigging, coating
         integrity surveys etc.) review of all pipe cut-outs and photographic material
         from repairs carried out by SAPREF over the years.




                                         Page 6 of 10
    Project No.: PP0220              Report No.: PR0259                     Revision No.: 0
     Summary Report: Study of the Integrity Management Practices and the condition of the
                  SAPREF transfer pipelines between the refinery and Island View.

        Discussions with OICCG(Oil Industries Corrosion Control Group).
        The PPT report was subject to an international peer review.


4        SUMMARY OF MAIN FINDINGS AND CAUSES OF LEAKS


         The main findings from this study are as follows:


         4.1.1   Corrosion by stray currents is the predominant failure mechanism on
                 the Transfer Pipelines, caused by the ineffective CP system. The
                 problem of stray currents has never been satisfactorily addressed, and
                 is the main reason why ongoing leaks have been encountered. The
                 CP system effectiveness has been poor for decades, and this report
                 has highlighted some of the problems with the existing CP system.
                 PPT has strongly recommended that a complete re-design and
                 upgrade of the CP system be undertaken immediately, followed by the
                 installation thereafter of an appropriate CP system, that will ensure
                 complete protection of all pipelines in the right of way (ROW).


         4.1.2   The external coatings on the MFO and MOGAS lines considered to
                 have been compromised due operation at excessive temperatures
                 during the 1960’s and early 1970’s. It has been recommended that
                 these two lines be re-wrapped in their entirety. Selective coating
                 refurbishment on the remaining transfer pipelines must be carried out
                 as part of ongoing annual maintenance, and must be based on new
                 coating survey data and pigging data.


         4.1.3   During recoating of the MFO and MOGAS lines the width of the ROW
                 will have to be excavated in its entirety to properly expose the MFO &
                 MOGAS lines. SAPREF may elect to use the opportunity to re-wrap
                 the other five pipelines which would be exposed in the same trench
                 during excavation of the MFO and MOGAS lines.


         4.1.4   SAPREF have re-wrapped significant sections (± 30%) of the various
                 transfer lines based on coating survey inspection data and in-line
                 inspection data.




                                         Page 7 of 10
Project No.: PP0220              Report No.: PR0259                     Revision No.: 0
 Summary Report: Study of the Integrity Management Practices and the condition of the
              SAPREF transfer pipelines between the refinery and Island View.



     4.1.5   “Tightness Testing” is carried out monthly by SAPREF, and
             hydrostatic testing carried out annually. The proposed testing
             frequencies would be considered adequate, with tightness testing
             carried out more than what is typically required at similar installations
             in the Middle East and North America. The proposed test pressures
             also meet the requirements of internationally accepted codes.


     4.1.6   SAPREF have developed detailed Risk Based Assessment (RBA) and
             Risk Based Inspection (RBI) documentation on the “Management of
             Transfer Lines” and describes the management requirements for the
             transfer pipelines between the refinery and the terminal. The purpose
             of this document is to ensure that all parties are aware of their
             responsibilities and activities, as required to ensure pipeline integrity.
             The proposed inspection plan (RBI) is similar in approach to the Direct
             Assessment Methodology in use in North America and contained in a
             Recommended Practice by NACE (RP0502-2002). This document is
             critical as it details SAPREF’s risk assessment approach to pipeline
             integrity. PPT is satisfied that the Risk Based Assessment (RBA) and
             Risk Based Inspection (RBI) Plan implemented by SAPREF is sound
             from an engineering perspective, and as it is a live working document
             is continually upgraded. The RBA & RBI plan will assist in establishing
             the integrity level of the pipelines and maintaining it for the future.


     4.1.7   Given the history of South Africa, the National Keypoints Act and the
             security risk of oil product pipelines in public areas, the right of way
             (ROW) is not clearly marked or identified. The ROW issues have not
             been adequately addressed by the refineries.




                                     Page 8 of 10
    Project No.: PP0220              Report No.: PR0259                     Revision No.: 0
     Summary Report: Study of the Integrity Management Practices and the condition of the
                  SAPREF transfer pipelines between the refinery and Island View.




5        RECOMMENDED PIPELINE INTEGRITY STRATEGY OPTIONS


Based on the findings of this study a list of the critical recommendations is detailed in
the Table below:


Item                        Action / Recommendation                                Priority
1        Cathodic Protection
1.1      Stray Current Survey (Completed in January 2004)                       Completed
1.2      Re-Design of CP System (in progress)                                   Immediate
1.3      Installation and Commissioning of new CP System                        Immediate
1.4      Set-up remote monitoring of CP Stations (completed).                   Immediate
2        Pipeline Coating System.
2.1      Re-Wrap MFO Line.                                                      Immediate
         At all locations where hidden cross bonds are located, bonding         to Short
         test posts are to be installed with individual cable connections       Term (0-2
         to all SAPREF and ENGEN pipelines.                                     Years)
2.2      Re-Wrap MOGAS Line.                                                    Immediate
         At all locations where hidden cross bonds are located, bonding         to Short
         test posts are to be installed with individual cable connections       Term (0-2
         to all SAPREF and ENGEN pipelines.                                     Years)
2.3      During recoating of the MFO and MOGAS lines (2.1 & 2.2                 Immediate
         above) the width of the ROW will have to be excavated in its           to Short
         entirety to properly expose the MFO & MOGAS lines. SAPREF              Term (0-2
         may elect (although not technically necessary) to use the              Years)
         opportunity to re-coat any other lines which are exposed in the
         trench at the same time.
3        Intelligent Pigging – ILI
3.1      Continue to Pig all lines on an annual basis until one year after      Once
         the following has been completed:                                      Annually.
         3.1.1 New CP system installed and Operating as designed.
         3.1.2 MFO and MOGAS Lines have been re-wrapped.
         3.1.3 If required by section 2.3 above, the Lubeoil line has
         been re-wrapped.




                                         Page 9 of 10
    Project No.: PP0220              Report No.: PR0259                     Revision No.: 0
     Summary Report: Study of the Integrity Management Practices and the condition of the
                  SAPREF transfer pipelines between the refinery and Island View.

5        Right of Way
5.1      Right of Way (ROW) Committee                                           Immediate.
         (SAPREF/ENGEN/Municipality/Community) to be established.
5.2      ROW policies and procedures to be developed.                           Immediate.
6        Risk Based Assessment & Inspection Programme
6.1      Finalise detailed RBA & RBI Document for the transfer lines.           Immediate.
         Current version is a “live document” being updated by
         SAPREF. Final document to incorporate review
         recommendations and clearly define SAPREF’s Integrity
         Management Plan.




                                         Page 10 of 10

				
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