bluuebunny/crossref_metadata_2025 huggingface dataset:
Stress Dependent Permeability in Low Permeability Gas Reservoirs: Travis Peak Formation, East Texas
Authors: Davies John P. , Holditch Stephen A.
Published: December 2007

This paper identifies factors that control stress dependent permeability in tight gas sandstones of the Travis Peak formation in East Texas, and presents a procedure for prediction of in-situ permeability at any value of net effective stress. Petrophysical analysis of core samples reveals that potential reservoir sandstones can be divided into 3 Rock Types; intervals of rock characterized by a unique response of permeability to stress. The rate of permeability decline with increasing net effective stress is different for each Rock Type and is controlled by three interrelated, pore geometrical parameters -- length, shape and short axis dimension of the pore throats. In these sandstones, permeability reduction is not controlled by the amount of porosity, shale volume, grain size, and volume of authigenic cements (silica, carbonate, and clay). Fundamental controls on pore throat size and shape are grain packing (nature of grain-to-grain contacts) and pore type (primary versus dissolution pores). Rock Type based equations are presented that allow for prediction of permeability and the amount of permeability loss for any value of reservoir stress.

The Rock Types can be identified using either laboratory measurement of permeability in core samples at different values of stress, or thin sections of rock samples, including cutting fragments. Algorithms are developed that allow for wireline log identification of each Rock Type using a basic set of log responses (Gamma Ray, Resistivity, Density/Neutron). A knowledge of Rock Type and porosity from wireline logs allows for prediction of permeability at any value of stress through zones of interest in non-cored wells.
Successful Application of Advanced Stimulation Technologies: A Multi-Field Case History
Authors: Caron J.D. , Froebel K.A. , Montgomery R.V. , Periman J.D. , Turner T.J. , Dunn K.P.
Published: December 2007

In early 1996, the Houston Division of Fina Oil & Chemical Company became involved in the Gas Research Institute's (GRI) Advanced Stimulation Technology (AST) Deployment Program through S. A. Holditch and Associates, Inc. During their involvement in the AST program (1996), Fina's Houston Division engineers were responsible for approximately 70 fracture treatments involving roughly 12,000,000 lb of proppant. The use of Advanced Stimulation Technologies on each treatment has provided multiple benefits:

- 5-25% increase in cumulative gas production (0.25-0.5 BCF/well) due to improved fracture treatment effectiveness,

- incremental 10 year NPV (10% discount factor) of $ 15 million and

- tangible cost savings of approximately $750,000 through a reduction in premature screen-outs and in treatment optimization.

Fina continued to utilize these advanced technologies in 1997, applying them to over 54 treatments involving approximately 11,650,000 lb. of proppant. This paper discusses the AST methodology and the successful implementation of these technologies in fracture stimulation programs performed in a variety of producing horizons in multiple fields throughout Louisiana, east Texas, and south Texas.

P. 407
Methods of Neuro-Simulation for Field Development
Authors: Doraisamy H.
Published: December 2007

This paper introduces a methodology for optimizing field development schemes. The use of numerical simulation models in establishing field development strategies is a widely practiced approach. In field development studies, a large number of scenarios which result in a time consuming and expensive process must be considered. The objective of this paper is to structure the field development schemes using artificial neural networks (ANNs) in conjunction with numerical reservoir simulation; a process we call neurosimulation. In neuro-simulation, a few field development scenarios are examined using a numerical simulator. The results of these studies are then used to train the ANN. The trained ANN is used as a predictive tool for field development purposes. Using neuro-simulation, the number of numerical simulations is significantly reduced. The use of the neuro-simulation approach becomes practical especially during the early life of the field when the recovery data and the field properties are sparse and sporadic. The neurosimulation approach provides the flexibility of considering any location as a potential site in contrast to the conventional simulation approach when the well locations are restricted to the pre-defined block centers. The neuro-simulation approach is faster and more efficient than its conventional counterpart. The results obtained from neuro-simulation compare well with the results obtained from a reservoir simulator.
Refork Completion Analysis with the Aid of Artificial Neural Networks
Authors: Shelley Robert F. , Stephenson Stan , Haley Will , Craig Ed
Published: December 2007

The quality and quantity of information available in the public domain is growing rapidly. Companies are creating in-house databases to track and improve operating and service performances in an effort to keep up with this explosion of data. The hardware and software used to obtain and manipulate massive amounts of information are constantly improving. All these events have created an opportunity to evaluate the complex interaction of variables and quantify how they relate to the required end result.

The Redfork formation is a prolific, low-permeability, natural gas and gas-condensate reservoir deposited during the middle Pennsylvanian Period. The reservoir is located in the deep Anadarko basin of west-central Oklahoma. The Redfork is an interesting reservoir because of its high level of heterogeneity and the varied stimulation/completion methods used in the formation. The volume and diversity of information available on Redfork completions make the Redfork formation unique.

This paper analyzes Redfork completions in Roger Mills and Custer Counties. The study uses artificial neural networks (ANNs) trained on a data set of 107 Redfork completions to analyze and quantify the effect of well/reservoir parameters and completion methods on production results. Specific areas of interest include controllable/quantifiable aspects of a well's completion/stimulation procedure that affect the production outcome. The paper will document a methodological test that supplements standard completion-optimization techniques.

P. 555
A New Pressure Transient Well Testing Method for Gas Condensate Wells
Authors: Jatmiko W. , Daltaban T.S.
Published: December 2007

One of the most important parameters for analysing wellbore pressure response in gas condensate reservoirs is the pseudopressure function. This function correlates the reservoir pressure and saturation distributions, and hence the non-linear governing equation can be transformed into a linear equation and solved using a standard method.

This paper describes a method of analysing wellbore pressure response of a gas condensate reservoir under transient conditions. In this study, the pressure distributions are calculated using iterative line source approximation and superposition principles. Initially, the steady-state saturation is assumed. The reservoir saturation distributions are estimated from the sandface saturation and the two-phase flow radius using a quadratic equation. The pseudopressure function is then calculated based on these distributions. The pressure distribution is then recalculated based on this saturation distribution. The material balance method is used to verity the saturation distributions. The dimensionless wellbore pseudopressure is calculated from the wellbore pressure data and compared with the dimensionless pressure (liquid solution).

In general the proposed method shows a good agreement with the liquid solution during transient conditions and hence it can be used to estimate the transport properties of gas condensate reservoirs.

P. 97
Effect of High Velocity on Pressure Transient Analysis of Multilayered Gas Reservoirs
Authors: Gomes E. , Reza Z.A.
Published: December 2007

Worldwide increased demand for natural gas has challenged researchers to come up with more accurate reservoir description and reserve estimation for natural gas. This study uses a semi-analytical model to study pressure transient behavior of multilayered gas reservoirs. Gas flow though porous media is complicated by pressure dependent fluid properties, reservoir heterogeneities, high velocity effect, etc. High velocity effect causes additional pressure drop at the wellbore which is a function of flow rate, fluid and/or rock properties very close to the wellbore. As a result of drilling, rock properties, such as porosity and permeability, in the vicinity of the wellbore are affected. Moreover, large pressure gradient very close to the wellbore causes pressure dependent gas properties vary in the radial direction. Using a semi- analytical model this paper studies transient gas flow behavior through a multilayered reservoir. Both crossflow and commingled layer situations have been considered. In this study, different schemes for calculating high velocity effects have been studied and evaluated. For the same amount of skin, both thin skin and finite damaged zone responses have been compared, It has been observed that for the same amount of skin, finite damaged zone and thin skin responses can be significantly different for gas reservoirs. Effect of permeability, layering, and different outer boundary conditions have also been studied.

P. 111
New Shape Factors for Wells Produced at Constant Pressure
Authors: Helmy M.W. , Wattenbarger R.A.
Published: December 2007

New shape factors are developed for bounded reservoirs produced by wells operating at constant bottomhole pressure. The new shape factors should replace Dietz shape factors (constant rate shape factors) when calculating the productivity of wells producing at constant bottomhole pressure; thus obtain a more reliable long term production forecast. Although the constant pressure and constant rate shape factors are conceptually different, they are close in value for regular shapes (square) with well in the center. However, for irregular shapes and off-centered wells, the difference is significant. The use of constant rate shape factors for predicting the performance of wells producing at constant bottomhole pressure results in over-estimation of well productivity.

P. 131
Effect of Heterogeneity on the Non-Darcy Flow Coefficient
Authors: Narayanaswamy Ganesh , Sharma Mukul M. , Pope Gary A.
Published: December 2007

An analytical method for calculating an effective non-Darcy flow coefficient for a heterogeneous formation is presented. The method presented here can be used to calculate an effective non-Darcy flow coefficient for heterogeneous gridblocks in reservoir simulators. Based on this method, it is shown that the non-Darcy flow coefficient of a heterogeneous formation is larger than the non-Darcy flow coefficient of an equivalent homogenous formation. This result is confirmed using numerical simulations. Non-Darcy flow coefficients calculated from analysis of well test data from a gas condensate field show that non-Darcy flow obtained from well tests that are significantly larger than those predicted from experimental correlations. Permeability heterogeneity is, therefore, a very likely reason for differences in non-Darcy flow coefficients often seen between lab and field data.

P. 215
A K-Value Compositional Model for a Retrograde Condensate Reservoir
Authors: Zhang Maolin , Mei Haiyan , Sun Liangtian , Li Shilun , Wu Qingsong , Kong Xiangyan
Published: December 2007

A new K-value compositional model for a retrograde condensate reservoir, which obtains K-value in a more effective way, and can cut down the time and the cost in the phase equilibrium calculation and simulation, is presented in this paper. The major physical phenomena and mathematical model used in the simulator are described. An application of both the K-value compositional model and the compositional model based on the equation of state to the examples of SPE4271, SPE12278 and a condensate reservoir in China is shown to have good consistency.
Breaking a Paradigm: Drilling with Tubing Gas Wells
Authors: de Leon Mojarro Jose C. , Terrazas Martin , Eljure Abraham Julian
Published: December 2007

Breaking a paradigm is to try to solve any situation with a different point of view and different sources. Everyone believes that for drilling a gas well, it is obviously necessary to use only drill pipe. Pemex Exploration & Production (PEP) is giving a tremendous change in this direction in the North of Mexico, in the area of Burgos Basin, Reynosa, Tamaulipas. PEP had successfully drilled more than 40 gas wells using upset tubing with WedgeThread Technology to drill the last section of the well, using the slim hole design and applying the "Tubingless Technique" for completion. This has given PEP the opportunity to save 30 to 40% of total cost of each gas well.

The conventional drilling programs used to be 17-1/2 in, 12-1/4 in. and 8-1/2 in. bit diameters and 13-3/8 in., 9-5/8 in. and 7 in. casing diameters respectively. This normally requires a 4 1/2 in. drill pipe for drilling the three sections, because the capacity of this pipe (torsion, tension and hydraulics geometry). Finally, the completion was performed with a 2-7/8 in. tubing with a permanent packer on top of the production zone.

The new drilling program requires 12-1/4 in., 8-1/2 in. and 5-7/8 in., bit diameters and 9 5/8 in., 7 in. and 3-1/2 in. casing diameters respectively. The 3-1/2 in. tubing has an integral connection on internal-external upset pipe with the Wedge Thread Technology to drill the last section and then it is cemented as a production casing (tubingless technique). Also this tubing has an amazing application to drill because its torsion, tension, bending and compression strengths. Therefore, this 3-1/2 in. tubing has a triple application: as a drill pipe, production casing and tubing.

P. 465
Investigation of Coiled Tubing Failures Over 2 Years and Corrosion Prevention Methods
Authors: Crabtree A. R. , Skrzypek H. , Eng P.
Published: December 2007

Fatigue life management of Coiled Tubing is widely applied in the industry today and this has led to a high reliability of Coiled Tubing used in the servicing of oil and gas wells. However, Coiled Tubing failures have not been totally eradicated from the industry and this paper examines some of the causes.

During a two year period, from January 1996 to January 1998, all coiled tubing, used by BJ/Nowsco which has failed before its predicted fatigue life has been examined to determine the nature and cause of the failure. This paper reviews some of these failures and highlights a trend which became apparent.

This trend towards a predomination of corrosion initiated failures has led to a study of prevention techniques and this work is also reviewed in this paper.
Downhole Tiltmeter Fracture Mapping: Finally Measuring Hydraulic Fracture Dimensions
Authors: Wright C.A. , Davis E.J. , Golich G.M. , Ward J.F. , Demetrius S.L. , Minner W.A. , Weijers L.
Published: December 2007

This paper introduces a new fracture diagnostic technology that allows economic mapping of hydraulic fracture dimensions. The downhole tiltmeter fracture mapping technology requires the use of an offset wellbore(s) for running wireline-conveyed downhole tiltmeter arrays. For the first time, hydraulic fracture dimensions including growth during pumping can be measured at a relatively modest cost. In addition to providing fracture diagnostic data (fracture height, width and length), this new capability allows enhanced utilization of hydraulic fracture models because model predictions can be "calibrated" with in-situ observations of fracture growth.

The concept is quite simple: creating a hydraulic fracture involves parting the rock and deforming the reservoir. Downhole tiltmeter mapping involves measuring the fracture-induced deformation in a nearby offset well(s) and solving the geophysical inverse problem to obtain the created fracture dimensions. The technology follows the same principles as surface tiltmeter mapping, but the different array geometry and placement make it very sensitive to fracture dimensions and less sensitive to fracture orientation - just the reverse of surface tiltmeter mapping. This paper will explain the fundamental concepts, the implementation strategy (wireline conveyed tiltmeter arrays, data acquisition, processing, and modeling), and three field case studies of measured hydraulic fracture growth.
New Acid System Minimizes Post Acid Stimulation Decline Rate in the Wilmington Field, Los Angeles County, California
Authors: Dean Gregory D. , Nelson Chris A. , Metcalf Steven , Harris Randy , Barber Terry
Published: December 2007

Acid stimulation treatments performed in the Upper Terminal (UT) Zone of the Wilmington Field, Los Angeles County, CA have been effective in removing formation damage caused by scale and fines migration. Unfortunately, most treatments have an average life of less than six months. A new Chemically Modified Acid (CMA) system has been implemented that utilizes a phosphonic acid in conjunction with hydrofluoric acid. This CMA system is pumped with a standard hydrochloric acid preflush and postflush. The phosphonic acid reacts with aluminum in clays and feldspars to form a temporary "protective film", thus allowing deeper penetration and more effective reaction of hydrofluoric acid on migratory silicates. Aluminosilicate solubility is not eliminated, but is controlled to allow a more uniform reaction. Another possible side benefit of the phosphonic acid is its ability to inhibit the formation of calcium carbonate scale.

Initial production rates of the wells acidized with this new acid system are approximately the same as wells previously treated with 9% HCl:l% HF, indicating removal of the damage. However, the real test of time has shown that the wells treated with this new system are producing at flatter decline rates, indicating either removal of additional fines or scale inhibition or both. Field data presented indicate an extension in the time to return to pre-treatment production rates from less than five months to more than nine months.

Laboratory data are presented that shows the improved solubility and deeper penetration of this acid system over conventional HC1:HF. Post-acid job flowback samples were also analyzed to determine the extent of silicate dissolution and to investigate the possibility of scale inhibition.
Spontaneous Water Imbibition into Diatomite
Authors: Schembre J. M. , Akin S. , Castanier L. M. , Kovscek A. R.
Published: December 2007

A systematic experimental investigation of capillary pressure characteristics and fluid flow in diatomite has begun. Using an X-ray CT scanner and a specially constructed imbibition cell, we study spontaneous water imbibition processes in diatomite and for reference Berea sandstone and chalk. The mass of water imbibed as a function of time is also measured. Imbibition is restricted to cocurrent flow. Despite a marked difference in rock properties including permeability and porosity, we find similar trends in saturation profiles and weight gain versus time functions. Imbibition in diatomite is relatively rapid when initial water saturation is low due to large capillary forces.
Characterising Curing Cement Slurries by Electrical Conductivity
Authors: Backe K.R. , Lile O.B. , Lyomov S.K.
Published: December 2007

Electrical conductivity is a parameter which can be used for monitoring the entire hardening process of oilwell cement slurries. The theoretical relationship between conductivity, porosity, cement chemistry, and ion content is discussed. The theory is confirmed by experiments; basically, the cement slurry conductivity decrease is a function of porosity decrease. The applied results show that the electrical conductivity of a curing slurry reflects both the strength development and the ability to resist gas migration.
Improved Reservoir Management Using Geostatistical Reservoir Description, 24Z Stevens Reservoir, Elk Hills Oil Field, California
Authors: Brown J.M.G. , Exakwe Nnaemeka
Published: December 2007

A reservoir simulation model based on geostatistical reservoir description was constructed for the 24Z Reservoir to evaluate competing reservoir management strategies. The geostatistical approach used the technique of collocated cokriging to assign reservoir properties to areas of the reservoir where sparse data exist. The fluid flow model scaled up from the geostatistical model was history matched with a significant reduction in the total number of simulation runs.
Norm Survey and Control System in the Oil Production Facilities in Egypt
Authors: El-Ghazaly S. , Hassib G. M. , Huseen Nagwa H.
Published: December 2007

Naturally occurring radioactive materials (NORM) have been known to exist in the petroleum industry for many years through the well logging operations. NORM was first recognized as a potential health problem as long ago as 1904 in the oil fields of Canada. It became an issue in the North Sea Oil and Gas Production Facilities in the early 1980 and became more widely recognized in the United States in 1986 in the States of Mississippi and Louisiana. Since then, NORM have been considered as a potential radiation source in the petroleum industry which needs to be controlled to maintain safe working conditions and clean environment.

In Egypt, the Atomic Energy Authority (AEA) and the Egyptian General Petroleum Corporation (EGPC) have initiated an extensive programmes since 1992. This programme includes radiation survey of the oil production facilities. The results of this survey show a wide range of NORM deposits starting from background level up to some hundreds uSv/h.

Accordingly, a NORM control system has been established which can be summarized as follow:

⇒ It is proposed to run a preliminary screening programme (ýPSP) for all oil fields to identify the level of NORM enhancement on each site. ⇒ The PSP includes a quick survey for the radiation dose rate on the surfaces of tanks, separators, de-salters, piping, disposal areas, etc. ⇒ Each site will be classified according to the following categories:- Controlled areas where the radiation levels exceed 7.5 uSv/h.Supervised areas where the radiation levels lay between 2.5–7.5 uSv/h.Screened areas where the radiation levels are less than 2,5 uSv/h. ⇒ Category A, requires:- Detailed radiation survey every 3 months, radiation measuring instruments, assignment of restricted areas, radiation personal dosimetry, supervising any de-sludging activities, training and NORM waste disposal programme. ⇒ Category B, requires:- Detailed radiation survey every 6 months, radiation measuring instruments, supervising any de-sludging activities, training and NORM waste disposal programme. ⇒ Category C, requires:- Radiation screening every 2 years and, training (Optional).

The present paper includes the results of the radiation survey, the radiation protection measures taken and the NORM disposal programme.
Removal of Dissolved Hydrocarbons from Production Water by Macro Porous Polymer Extraction (MPPE)
Authors: Pars H. M. , Meijer D. Th.
Published: December 2007

This paper presents the successful application of Macro Porous Polymer Extraction (MPPE) technology to remove hydrocarbons from the produced water of a natural gas plant. This water is discharged to the public watertreatment facilities and is subject to a maximum hydrocarbon contents. Elf Petroland together with Akzo Nobel investigated the use of a Macro Porous Polymer filled with an extraction liquid for hydrocarbon removal. A MPPE unit was installed June ‘94 at Elf Petroland in Harlingen (The Netherlands), downstream the reflux drum of the DEG/TEG regenerators and treated the condensed water stream. The unit proved to be very efficient. The hydrocarbon content was reduced from approx. 2000 mg/l to less than 0.5 mg/l. Since May ‘97 the performance is tested for the treatment of all produced water (process-, formation-and wastewater) to a maximum benzene concentration of 100 ug/l.

MPPE utilises two proven technologies, liquid-liquid extraction and steam stripping with an innovative medium (the MPPE particles). Hydrocarbon contaminated water is passed through a column packed with MPPE particles. An extraction liquid immobilised within the polymer matrix removes the hydrocarbons from the water. The purified water passes out of the column directly for reuse or discharge. All hydrocarbons with a relatively high affinity for the extraction liquid (compared to water) are removed. Periodical in-situ regeneration of the extraction liquid containing MPPE particles is accomplished with low pressure steam. The steam volatises the hydrocarbons. Volatised hydrocarbons are condensed and then separated by gravity. The hydrocarbon phase is recovered and sold as product, the water phase is recycled to the system.

Besides the Harlingen pilot, the unit is proven successful in other branches of industry. At present fourteen units are operational or under construction in the USA and Europe, of which six treat process water and eight are used in the field of groundwater remediation. Removal efficiencies up to 99.9999 % are achieved for a wide varieties and combinations of aliphatic, aromatic and halogenated (e.g. chlorinated) hydrocarbons.
Dilution and Bioavailability of Produced Water Compounds in the Northern North Sea. A Combined Modeling and Field Study
Authors: Johnsen S. , Røe T. I. , Durell G. , Reed M.
Published: December 2007

A combined field and modeling study addressing the dilution and spreading of produced water originating polycyclic aromatic hydrocarbons (PAH) has been carried out in the Tampen region, located in the Norwegian sector of the Northern North Sea. Sampling sites were identified in the region and located in positions near production platforms and in open sea. The station network was designed to cover areas expected to have elevated levels of produced water originating PAH as well as areas not influenced by these discharges, based on dilution modeling of produced water discharge data for the Norwegian and British sectors. Five different sampling techniques were applied in this study. These were deployment of blue mussels and semi-permeable membrane devices (SPMDs) along with direct water sampling for solvent and solid phase extraction and in situ large volume water sampling. Using these results obtained with these techniques, the water concentrations of two selected PAH were compared to regional concentration fields from dilution modeling of produced water discharges from all platforms in the area (Norwegian and British sectors). The results showed that increased levels of PAH in the water phase could be found as far away as 10 km from the nearest discharge source. The agreement between the observed PAH levels and the corresponding levels suggested by the model were very good for the two components included in the present study. As could be expected, the model failed to detect local effects close to the discharge point, when the model was operating on a regional scale.
Evolution of Produced Water Treatment in Campos Basin
Authors: de Castro J. F. Tebaldi , Bastos E. Costa , Shioya N. Hiromi
Published: December 2007

It's shown the usual technologies in Campos Basin platforms during the last years, and the evolution that can be seem on the new production platforms as floating production storage and offloading systems and semi submersibles production plataforms. The conclusions of each step are indicated.

It's discussed the sequential actions, always looking for simple solutions, with low costs and easy installation.

The main contribution is to emphasize concepts that are very valuable and important to the operation, increasing effectiveness and improving results.
Mangrove Restoration Techniques: The Mahakam Delta
Authors: Suripno Suripno , Sulistiyono Sulistiyono , Dutrieux Eric
Published: December 2007

In the last 50 years Indonesia's mangrove has been degraded by more than 11 million hectares. As mangrove has an important role from ecological point of view, the remaining mangrove must be certainly protected and restoration must be done as well to the damaged mangrove. Mangrove provides ecosystem as nursery and feeding ground for numerous species of fishes and shrimps and also protects the shoreline and many other important roles of mangrove. Mangrove ecosystem has a value based utilization both its product and benefit to human.

The Mahakam Delta is a sensitive ecosystem that is mainly covered by mangrove. It is located at the mouth of Mahakam River in East Kalimantan Indonesia. In this area, TOTAL Indonesie has undertaken its E&P operation since 1974. Taking into account the sensitivity of mangrove, TOTAL Indonesie has performed mangrove restoration as a part of its environmental management plan. In two different locations, i.e. Senipah Oil Terminal and Handil Field, there was mangrove rehabilitation in two different ways. Planting new seeds from other location with full human intervention performed the restoration in Senipah Oil Terminal. For the second case of Handil field, there was a natural restoration in the cleared mangrove area. Human intervention was only needed for maintaining the natural seedling.

The above efforts of mangrove restoration have successfully transformed the poorly vegetated areas to become mangrove forests. The mangrove restoration is a proven effort of Total Indonesie's commitment in environmental protection of mangrove ecosystem.
Sidki Well Abandonment and Platform Removal Case History in the Gulf of Suez
Authors: El Laithy Wael F. , Ghzaly Sayed Mansour
Published: December 2007

On December 8, 1989 the Sidki Drilling platform owned by Gulf of Suez Petroleum Company (GUPCO) in Egypt was struck and severely damaged by a cargo ship when venturing outside of designated shipping lanes in the southern Gulf of Suez. Sidki "A" platform was a 12-slot load bearing structure located in 278’ of water. At the time of the collision, nine (9) wells were producing approximately 5000 BOPD. The collision rotated and tilted the platform deck resulting in rupturing well risers and severely damaging numerous wellheads. The collision rendered the platform a total loss.

Several measures to control wells and the resulting oil pollution were taken. Assessment of structural damage was conducted and a plan formulated to plug and abandon the producing wells followed by decommissioning and abandonment of the facilities and site remediation. This process went through three (3) phases.

Immediate action to control/secure wells, stabilizes the Damaged structure and pollution control. Securing the wells in such a manner that each well could be accessed and permanently plugged and terminated at the mudline utilizing a jack-up rig. Decommission of under water and topside facilities, removal and disposal of the damaged structure.

This paper will present Gupco's experience in controlling the damaged wells and damaged structure with strong emphasis on safety and environmental impact. It will conclude with three phases of facilities abandonment, removal and disposal.

Lessons learned and post appraisal will be included to improve the process of future decommissioning and removal of facilities.
A Decommissioning Alternative for Offshore Structures in Venezuela: Artificial Reefs
Authors: Guevara Marcel J.
Published: December 2007

The decommissioning of offshore structures has increasing importance for the international oil and gas industry. Venezuela has several structures in Lake Maracaibo, and is currently planning the development of its oil and gas resources in the Caribbean Sea. The possible alternatives for decommissioning offshore structures are analyzed based on experiences in different countries and interviews with key individuals and organizations on their positions, perspectives, and willingness to participate in proactive and innovative solutions. The main findings are the need for specific terms and guidelines. Special attention is focused on turning structures into artificial reefs.
The Global and International Regulatory Regime for Decommissioning Disused Platforms
Authors: Griffin William S.
Published: December 2007

World regulators and authorities began almost 40 years ago to develop regulations for decommissioning offshore installations. The regime established reflects a balance between the need to protect the environment, navigation safety, fishing and other users of the sea and takes into account the safety of workers, technical feasibility and cost. When all factors are considered the current regime is strict, comprehensive and allows the coastal state authorities to exercise discretion with a case-by-case approach.
Development, Implementation and Registration of an Environmental Management System (EMS) to ISO 14001
Authors: Craddock Henry A. , Martin Irene
Published: December 2007

This paper will address the successful implementation of an environmental management system registered to ISO 14001 (1) in an oilfield service company. The EMS covers both onshore and offshore requirements and works within the highly regulated environment of the UK sector of the North Sea. The paper presents a historical case study from initiation and preliminary review, through implementation to successful registration of the EMS to ISO 14001.
Biodegradation of Chemicals in the Marine Environment: Towards Harmonised Protocols
Authors: Garland E. M. , Tozzolino P. , Dutrieux E.
Published: December 2007

Biodegradability of chemicals in the marine environment is a key parameter for environmental impact assessment of the discharge of chemicals used offshore. Until now, no protocol had enjoyed the support of the whole scientific community. Within the context of harmonisation of the chemicals used in the North Sea offshore industry, there was an urgent need for a reliable method. This meant the necessity to define new protocols and to ring test them.

Elf Petroleum Norge undertook the work. The choice and definition of the protocols have been the subject of considerable discussion. Finally, four were retained, based on various different principles of measurement. Tests were performed in eighteen European laboratories. The results were discussed in a debriefing workshop the conclusions of which were as follows:

- the relevance of the four protocols was demonstrated; - assessment of the biodegradability of the four substances tested was the same, whatever the protocol used; - the principle of measurement used in the test made no significant differences to the results obtained; - each protocol gave comparable results but had different advantages and disadvantages; - sodium benzoate could be selected as a reference substance.

Therefore the choice of the most suitable protocol for a specific application remains open: allowance must be made for the characteristics of the laboratories considered and even, in particular cases, of certain properties of the substances tested. In the light of these results, the Oslo and Paris Commission was invited to approve the four protocols ring tested.
Optimizing The World-Wide Application of HSE Management Systems - An International Drilling Contractor's Experience
Authors: Stibbs W. , Lewis S. J.
Published: December 2007

As an international drilling contractor, Sedco Forex needs to meet the health, safety and environment (HSE) requirements of many external parties such as flag states and classification societies, local regulators and oil company clients. To do this, Sedco Forex has a core ‘QHSE Management System’ against which we conduct our operations world-wide and which allows us to interface with all of these parties and effectively manage both external requirements and our own internal requirements. We have made extensive use of information technology (IT) to communicate the QHSE-MS world-wide and also to conduct formal demonstrations of HSE management for our rigs, HSE Cases. We have learnt many lessons over recent years on how to implement effectively formal assessments and improve our HSE performance. The bottom-line is our commitment to total quality management (TQM) which provides the framework for assuring that the prevention of accidental risk and loss to process is a recognized and integral part of our continuous improvement culture.
Vessel Traffic Service (VTS) on the Norwegian Continental Shelf
Authors: Arvesen B. , Ystebo O. , Haram A.
Published: December 2007

In the North Sea, with heavy traffic, there is always a probability for collision between platforms and larger cargo vessels and tankers.

In order to create a recognised maritime sea picture, real time information is necessary. This is done by combining Radars, Transponders and remote controlled communication equipment. This gives the shore based VTS center the opportunity to make direct intervention and thereby avoid collissions.
Driving Monitor, Another Spanner in a Manager's Toolbox for Safety Management
Authors: Cocianni V. , Taviansky R.
Published: December 2007

This paper discusses the advantages of the installation of driving monitors to review individual driver's on-the-road habits. The driving monitor used is a simple and relatively cheap model, obtaining data on total distance traveled, number of accelerations and decelerations (sharp braking) above defined limits, time traveled above a certain limit and the maximum speed attained. An index is proposed combining this data into a simple number able to show the tendency of a driver or the location over time. The results so far have shown a general downward trend in this index which by no means signifies that driving accidents will not happen but, at least, if one was to happen, it would be at a lower speed than before and/or with a greater braking distance, leading to less catastrophic results. The driving monitor is one more tool available to the manager to improve the chances of avoiding motor vehicle accidents, and contribute to the success of the already-in-place HSE Management System.
Introduction of Driver Monitors in Venezuela
Authors: Nutter James G. , Corbett David
Published: December 2007

Venezuela is a country with varied terrain, mountains in the west to swamps and marshes in the east with many open plains in between. Safely operating vehicles in this environment is challenging. The roads range from paved multi-lane highways to unpaved dirt roads. Due to operating constraints, special purpose (four-wheel drive or heavy duty) vehicles are not used by the majority of the companies operating here. Normal street vehicles are used in both city and field operations. The use of driver monitors has been mandated as part of an Anadrill company-wide QHSE policy; however, in Venezuela these monitors have a direct impact on health, safety, environment, and cost.
Offshore Explosions - Recent Research and Its Impact for Industry and the Regulator
Authors: Renwick P.D.
Published: December 2007

Modern UK offshore legislation requires certain risks, including those of explosion, to be assessed and reduced to a level as low as reasonably practicable (ALARP). The development and effects of explosion in the confined, congested spaces encountered offshore are very difficult to predict and none of the methods available can be described as fully validated it is apparent from HSE's Safety Case assessment that different models produce significantly different predictions for quite similar situations.

Recent research, including full scale experiments in a rig simulating a "typical" offshore module and the comparison of experimental results with "blind" predictions by several explosion modelling agencies, found: that the models produced a wide scatter of predictions; that measured overpressures were significantly greater than the blast resistance of many topsides structures; and that the application of water spray prior to ignition produced significantly lower overpressures. Work to understand and quantity the latter effect continues; results to date are reported.

Many commercial models have now been adjusted to take account of this research, and models remain essential design tools, but their predictions must be treated with caution. A number of installations in UK waters have been improved significantly as a result of this assessment process and some newer installations are being designed to include much stronger blast walls (to withstand over-pressures up to, or even beyond, 4 bar) than have previously been specified. Some operators have also adopted a strategy of bringing water deluge systems into operation on confirmed gas detection but this is not yet common practice. Some considerations affecting the use of deluge systems in explosion mitigation are discussed.
Risk Ranking HAZOP Recommendations as Part of a Coherent Risk Management Program
Authors: Stevens G. C.
Published: December 2007

Many Oil and Petrochemical companies devote considerable resources to hazard identification exercises such as HAZOP studies. A large number of recommendations are generated but progress is often difficult and the amount of work is typically well beyond available budgets.

This paper describes an approach to prioritising HAZOP recommendations and assessing the benefits cost aspects of alternative initiatives. Most importantly the method puts the proposed safety expenditure within the context of existing Risk Management programs including Insurance and alternative investment in other schemes to improve process performance.

In this way investment in safer operation is evaluated on the same basis as other business opportunities and within an overall framework of Corporate Risk Management.
New chemicals information system in NAM
Authors: Kuiper T. O. H. , Kruse W. M. J. , Hulspas F. L. M.
Published: December 2007

NAM has developed and implemented a flexible, intranet based system for providing chemical information at the work site on so called CHEMICS cards. These cards contain information on the safe handling of chemicals, associated risks and recommended procedures to be followed in case of an incident. Product details and transport information are also included. At present, the system provides cards in English, German and Dutch.
Cost of Risk
Authors: Talavera R. , Jimenez J.
Published: December 2007

For senior managers, the measurement of risk management performance is a never-ending battle. The lack of accurate equitable performance techniques can be a top management concern. In any performance measurement system, the available tools a qualitative and quantitative, balancing them out becomes a challenge. While there are many qualitative factors that can be used meaning risk management performance, such as communication to management, implementation of risk control programs and improvements in professional education, fewer quantitative tools exits. Currently, quantitative measures, tend to focus in control of insurance or direct less cost. Typical quantitative measures include measurement of insurance cost against budget, average claim size, and average age of outstanding claims. Unfortunately, these traditional measures focus only on a part of the organization's total risk cost, they do not take into account the interdependent cost relationships of risk assessment, risk control, risk financing and administration. The Cost of Risk (COR) concept recognizes that the activities and cost of managing risk includes more than just insurance premiums, it includes the management and responsibility for costs contained and retained losses, risk control expenditures, administration and insurance or risk financing. Normalizing these costs to sales, assets units sold a man hours enables management to determine whether total risk management costs are increasing, decreasing, or stable compared to a broad measure of the company's exposures or economic activity.
Implementing a Loss Costing System
Authors: Sparks Ronald L.
Published: December 2007

The E&P Forum has recently issued a set of new Loss Costing Guidelines. These guidelines serve as a method for controlling losses through consistently measuring them. Reductions in losses achieved in this manner will directly improve the bottom line of a company's balance sheet. This paper discusses the processes and key starting points for companies to use in a real-world implementation. Examples are used to illustrate how to move the concept from guidelines to design to application. Because of the focus on "how to", this paper will be of specific interest to the H.E.S. manager.
User Experiences with Accident/Incident Databases in the Norwegian Oil and Gas Industry
Authors: Aase K. , Ringstad A. J.
Published: December 2007

The paper focuses on some of the initial challenges in building standardized and shared accident/incident1 databases. Results from user inquiries, system evaluations, and analysis of accident/incident data in a specific reporting system are included. Results show that the work with accident/incident databases in Norwegian oil & gas industry has led to several positive effects such as an increased number of reported incidents, increased safety focus and improved data quality. However, implementing standardized accident/incident information systems has not been unproblematic. The relation between a standardized database structure and local adjustments is perceived as problematic, and likewise to use the accident/incident data beyond mere information processing. In addition, traditional problem areas within accident/incident reporting such as information quality, local use of the information, and lack of successful experience transfer were present.
The Interface between Kazakh and Western Medicine - the Best of Both Worlds
Authors: Simpson Stephen R.
Published: December 2007

This paper examines the current state of the health services in Kazakhstan, and the health of the population. It includes a review of environmental issues, and the historical background to provision of health care during the Soviet era. The incidence of disease, availability of treatment, and the cultural differences of both doctors and patients are also explored.
Medevac Procedures and Statistics
Authors: Singh Amar
Published: December 2007

Medevacs form an integral part of the overall Company's Emergency Response Procedure. Medevac is a Medical Evacuation activity made or carried out in response to serious illness or injury, where ‘life or limb’ is at risk. It entails an evacuation of a patient, usually following a visit by a doctor or an experienced medic to the victim at the Emergency site. This action is necessary in order to prevent death or further serious damage to the victim's health. Medevacs have priority over other activities. Any one medevac poses a number of challenges and any delay or indecisiveness will invariably jeopardise the patient's life.

Prior to 1991, all medevacs in SSB/SSPC were initiated by the duty Medical Officer usually after consultation with the emergency site medic. This arrangement had posed a number of problems like difficulty in locating the duty Medical Officer, "indecisiveness" on the part of the Medical Officer etc. In May 1991, the medevac procedures were redrawn. Major change being that the "Emergency Site Supervisor" (or Platform Supervisor) taking over the responsibility of initiating the medevac rather than the duty Medical Officer. This change had significantly improved the carrying out of medevacs.