Risk Factors in a Process of Gas Supply Pipeline Construcion

. The paper applies to the risk management in the specialized construction by the example of construction of a high-pressure gas supply pipeline. The specific character of the construction project has an impact on the scope and types of risks which may occur and adversely affect the outcome of the project. The paper aims to indicate the groups of technological tasks which need to be carried out when constructing a gas supply pipeline, the associated factor risks and the quality control method as a tool of mitigating the level of risk.


Introduction
Investing in a gas supply infrastructure is a costly, complex and multi-step undertaking. Since such infrastructure is a strategic component of a national energy supply system, which is designed to provide energy supplies for production and service processes, for the needs of collective and individual heat supplies, its reliability and uninterrupted operation must be ensured. Every participant of an investment process (an investor, a designer and a contractor) has to be fully aware of the requirements and bear liability for the tasks they have undertaken to perform. Therefore, appropriate supervision and control become a key element of a construction process with the view to acknowledging and ensuring that a given facility will be built in compliance with the construction law, the conditions specified in a building permit, the applicable regulations and standards as well as the investor's demands.
The character of a gas supply pipeline construction project has an impact on the scope and types of risks which may occur and adversely affect the outcome of the project. The paper aims to indicate the groups of technological tasks which need to be carried out when constructing a gas supply pipeline, the associated risks and any ways in which risks may be mitigated using the right quality control methods. The study is based on the actual historical data (documentation of the gas pipeline constructions in the period of 2012-2017), from the polish STALPROFIL S.A. (joint stock company) group experts' information (employees) and the literature on the subject. The methods of risk analysis in the construction had been based on the theoretical approach described in [1,2]. The risks in the pipeline construction projects may be of different origin, including: design risk, management risk, construction risk, subcontractor risk, political/governance risk, economical/financial risk, owner generated risk, material risk and equipment generated risk. However, in this paper we concentrate on construction risk. The construction risk remains in relation with the majority of other listed above risks [3].

Risk factors and the specific groups of technological tasks in a gas supply pipeline construction process
Construction activities related to linear facilities are exposed to a variety of risks and hazards, the occurrence of which may significantly distort the process and lead to e.g. delays, cost overruns and, in some extreme cases, discontinuation of a project or a failure to complete a given task.
Making a decision on the participation in a tender or on the acceptance of a contract, a party involved should be fully aware of any unfavourable events which may occur and should be able identify these in an effective way. Such unfavourable phenomena or risks of a given project should be carefully and meticulously specified and documented. An analysis of risk factors, the determination of preventive actions, the assignment of personal responsibility and the scheduling of periodic or continuous monitoring of both the formerly identified and the new risks, may help us find the right directions for actions, mitigate these risks and protect our operations from the consequences of such undesirable events. All these efforts, when conducted in a planned manner, will create a system to implement a risk management policy.
The risk analysis for the construction of a gas supply pipeline shows that the process is highly complex and covers many stages, which can also be translated into the scope and extent of risks that may have a negative impact on the outcome -the aim of the project. In the study 16 groups of the technological tasks which are performed when producing a gas supply was taking into consideration. The study identifies 116 risks which are specific to the construction of gas supply pipelines ( Table 1). The risk factors, which have been established, are ranked according to the weights assigned to them. The weights has been estimated as the normalized (between 0 and 1) result of multiplication of the probability of occurrence (from the historical data) and the cost. This gives an overall picture of what risks may be considered critical, i.e. which risks are expected to have the biggest impact on the construction process failure or success. The risks were divided into three groups: high risks (risk weight 0,200-1,00), moderate risks ( risk weight 0,050-0,200) and low risk (risk weight less than 0,050). Then the risk factors were assigned to groups of technological tasks ( Table 2). The most vulnerable technological tasks are: welding, connections in trenchless technology technological facilities -gas units. The failure in these groups of technological tasks can be easily detected by standard quality control methods (e.g. x-ray inspection). However the other risk factors can not be neglected as the risk occurrence is usually described as critical in pipeline industry.

Conclusion
The failure of the high-pressure gas pipeline would be extremely dangerous for both people, civil engineering constructions (including buildings), and environment. Therefore the use of any method which will diminish the probability of occurrence of such an event is necessary. The process of the construction of the gas pipeline is very complicated and many risk factors can occur. The critical factors can materialise at different stages of the construction process. Therefore the in-process risk management is a proper tool in these cases. Additionally, such an approach is used widely in infrastructural construction projects [e.g. 4]. Having identified the main risk factors in the pipeline construction process (as stated above) one can try to manage it. The main tool of risk management in the industry is quality control (eg. [5]).
The purpose of quality control is to check and assess, in an independent manner, the compliance and the progress of a construction process in order to ensure that the planned work quality is met. A contractor which builds the given gas supply pipeline is responsible for the correct application of technologies and for the quality of materials to be built in at every stage throughout a project delivery process, assuming the risk of any potential failure to perform or duly perform. That is why it is so vital to have well-qualified staff, whose members are well-organised and will carry out control activities, as set out in the project and tender documents, resulting from the legal status and required by the investor. In case of a highly complex construction project, the contractor may draw on their subcontractor's expertise and experience from conducting similar assignments, also in the area of quality control. Quality control staff should act within an established system of control, be provided with the necessary documents, equipment and measuring devices to enable them to evaluate the quality of work. The contractor, in the course of the construction process, should carry out all tests, examinations and checks needed to verify the compliance of the work performed with the requirements specified in the technical design, the technical terms and conditions of delivery and acceptance, all the applicable standards and the investor's guidelines [6].
When it comes to highly complex projects, in particular the ones in which the occurring risks may negatively affect human health, lives, the natural environment or result in substantial financial losses, it would definitely be advisable to implement in-process control as a tool for monitoring and mitigating risks. Such procedures are commonly applied in the pharmaceutical industry [7,8]. They assume that the next stage of a project may not be started until the previous one has been reviewed in terms of its compliance with the quality targets established for this phase. Owing to in-process quality control the planned quality of project deliverables can be ensured and the entire process can be controlled. To be sure that such tasks are performed in a reliable manner Quality Assurance staff and production workers need to be given autonomy (independence). Such an approach tends to be adopted in the construction business [9]. It is part of a total quality control system and it is used especially in cases when no faulty component may be allowed to appear throughout the process. Although it is impossible to expect any construction process to run without any possible faults, quality may be significantly boosted and potential risks can be considerably limited and prevented from occurrence [10,11].