Journal of Environmental Protection, 2012, 3, 394-399
http://dx.doi.org/10.4236/jep.2012.35049 Published Online May 2012 (http://www.SciRP.org/journal/jep)
Oil/Gas Pipeline Leak Inspection and Repair in
Underwater Poor Visibility Conditions: Challenges and
Perspectives
Agbakwuru Jasper
Offshore Engineering, Faculty of Science and Technology, University of Stavanger, Stavanger, Norway.
Email: jasper.agbakwuru@uis.no
Received February 29
th
, 2012; revised March 22
nd
, 2012; accepted April 15
th
, 2012
ABSTRACT
Mechanical pressure clamps are examples of innovative tools commonly used in the oil and gas industry for arresting
leaks from damaged oil and gas pipelines. However, if leaks result from pipeline rupture, clamps are not usually rec-
ommended. It is therefore obvious that inspection of the leaking pipeline is very crucial in deciding the strategy for re-
pair. For subsea pipelines where underwater poor visibility is pronounced, this important aspect of the pipeline repair
process becomes difficult to implement. The result is a repair-leak-repair cycle. This challenge is commonly found in
repairs of old pipelines in unclear water conditions. Old pipelines and their vulnerability to fractures that often lead to
ruptures are discussed. In this paper, the challenges and technologies available for visualisation and examination in such
unclear water conditions are discussed. There appears to be a gap in the existing pipeline integrity management system
with respect to inspection and repair of pipelines in unclear water conditions. This gap needs to be filled in order to
minimise spills and pollution. For pipelines installed in unclear water condition, a perspective is suggested to extend the
capability of existing remotely operated vehicles to employ the use of clear laminar water system or a related technique
to provide integrity engineers and operators with close visual assess to inspect leaking pipelines and effect adequate
repairs. This paper suggests that the use of optical eye as the main tool for examination remains valuable in managing
the challenges in underwater pipeline repairs in unclear water condition.
Keywords: Pipeline; Leaks; Detection; Spill; Close-Visual Inspection; Pipeline Repair; Pipeline Inspection
1. Introduction
The pipeline integrity engineer takes responsible care of
the pipeline system by applying an adequate Pipeline
Integrity Management System (PIMS). The pipeline in-
tegrity management system encompasses all efforts to
ensure the pipeline is secured and safe to operate. This
implies adequate inspection and maintenance, ensuring
fit-for-service, operational control and monitoring, adequate
repair systems in place should the need arise, trained
personnel, regular audits and risk assessments etc. and
more importantly, a management system to harness these
activities. These efforts create an opportunity for the
pipeline operator to have full control over the pipeline
life and functionality.
There is today, evidence of repair-leak-repair cycle
involving underwater pipelines in poor visibility condi-
tions [1]. This is particularly common in pipelines often
classified as “old” pipelines. This is against the object of
PIMS and represents a gap. The poor underwater visibil-
ity is often due to inorganic and particulates of organic
substances swept into the open water or sea by tidal ac-
tions, rain water, wind, industrial processes etc. This prob-
lem creates room for oil spills with its attendant social,
economic and environmental damages.
It is also noted that in some developing countries,
there is an increasing trend for inspection of damages on
pipelines by joint investigation teams to determine whether
a spill is caused intentionally or not. Unfortunately, the
joint inspection exercise is a prerequisite requirement for
pipeline repairs in some regions of the world [2]. It is
therefore desirable that agreement between the stake-
holders in the joint investigation team be resolved as
quickly as possible using a suitable close visual inspec-
tion or related technique. Quick resolution of causes of
damages for submerged pipeline causing spills in un-
clear/muddy water may be difficult with the present in-
dustry tools.
This paper intends to explore the reasons for the in-
spection and repair difficulties and proposes an approach
towards development of systems that could provide ef-
fective solution to oil/gas/liquid pipeline inspection and
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