For the past fifteen years, industry, academia, government, environmental organizations and other stakeholders have worked together in a collaborative program to provide unbiased science to address environmental and societal issues associated with oil and gas activities. The research team has performed over 40 field trials related to land, water and emissions measurements. Case studies and specific examples on advancements in technologies and processes that have addressed land, emissions, water, stakeholder engagement, and other aspects are discussed. Also discussed is internal progress within industry to ensure that the workforce develops a culture of environmental awareness. Evolvement, aided by this collaborative effort, has been substantial. New technology developed has reduced land impacts through extended reach and horizontal drilling techniques, implementing new, energy-efficient rigs, and improving logistics coordination. Noise and lighting have also been addressed. Emissions have been reduced throughout drilling, completion and production operations through reduced drilling times, electrification of various processes, and flaring reduction. Operators have increased the recycling and use of produced water throughout completion operations and are implementing voluntary water conservation efforts. Public engagement by operators has increased acknowledging that stakeholder engagement is an important aspect of how to address environmental concerns. The team has developed novel methods, for example the development of virtual sites using gaming software, to enable stakeholders to become aware of the importance that industry places on addressing environmental aspects. How industry has successfully communicated advances in environmental stewardship is also discussed.

A strong economy, industrial base, and low cost of living have led to a significant rise in population in the Greater Houston Metropolitan area of Texas, and with it, an increase in production of sewage and biosolids wastes. In the Houston area, sewage is treated with a combination of anaerobic digestion and lime stabilization to create biosolids which are then pelletized into fertilizer, composted, landfilled, or land applied. The Slurry Injection technique is an alternative treatment and disposal method, that can replace much of the capital costs associated with maintaining and expanding the wastewater treatment infrastructure in Houston at significantly lower capital cost. This technique utilizes the principles of Drill Cutting Injection which has been implemented in petroleum industry since mid 1980s for oil and gas waste management. A biosolids slurry injection facility of sufficient capacity to dispose of all the biosolids currently produced by the city of Houston could be installed for less than 1/10 of the nearly $526 million in capital currently budgeted by the city to expand the current system under the current rolling 5-year plan. A substantial reduction in greenhouse gases is achieved as well, by using the slurry injection technology as the Carbon Dioxide and Methane (which are prominenet greenhouse gases) produced by biosolids degradation is completely sequestered under deep geological formation and along with it the emissions produced during dewatering and transportation of biosolids is also eliminated. The City of Los Angeles’ Terminal Island Waste Water Treatment Plant facility has deployed the slurry injection technology since 2010. It currently disposes of approximately 20% of biosolids of the city of Los Angeles. This paper describes the economic and environmental aspects related to biosolids management and the formation evaluation carried out to inject the bioslurry in greater Houston. The study includes both the economics of the surface construction requirements as well as the science behind the subsurface strata evaluation for containment assurance. For the subsurface aspects, a geomechanical and stress analysis is performed on two different formations (the Frio and the Vicksburg). A significant confining layer is present above and below our targeted injection zones, which restrict and assure the injected waste remains contained. Also, hydraulic fracture simulation and analysis provides an assurance and the waste containment within the engineered subsurface strata/formation for permanent storage.

Oklahoma has been at the center stage of induced seismicity. Water-disposal activities have been attributed to trigger the increasing number of seismic events. The objective of the study is to provide a simple diagnostics method and procedure for safe water-disposal operations. A comprehensive suite of scenarios and parameters has been analyzed that affect water disposal. Prognosis based on this study will lead to safe water-disposal operation without the adverse effect. A suite of reservoir models involving water injection helped understand disposal-well performance. The well operational limits correspond to disposal-zone fracture gradient. The modified-Hall analysis is employed to ascertain the point of departure from normal injection behavior. Limiting cumulative injected volumes are determined and investigated for various scenarios from simple to increasingly complex subsurface conditions. This investigation includes studying the effects of disposal-zone storativity, compartment size, conductivity, formation compressibility, heterogeneity, and natural fractures. Additionally, we explored the effects of communication with overlying producing zone, communication through completion anomaly, seal integrity and fluid complexities. This study illuminates an overall understanding of disposal-well performance through various scenario analyses. A relationship of disposal zone fracture gradient and limiting cumulative injection volume is established. For a fracture gradient of 0.7 psi/ft, this limiting pore-volume injection is less than 2%, which corresponds well with the conventional wisdom learned from CO 2 injection-well performance. The relationship of disposal-zone compartment size, established with rate-transient analysis, with limiting cumulative injection volume is formulated. Analyses from the various statistical design of experiments reveal the important variables that may affect disposal-well performance. The disposal-well operation can be devised in real time using the modified-Hall analysis that can reveal the departure from normal injection-well behavior. Factors accentuating the departure from normal behavior include disposal-zone storativity, formation compressibility, and seal integrity. Situations, where pressure release through leaks or communication with an adjacent formation takes place, will naturally accommodate a larger volume of disposal water. Also, we learned that limiting cumulative injection volume and not injection rate (assuming injection pressure gradient is less than the fracture gradient) triggers a departure from normal injection behavior. Using a suite of numerical reservoir models and the reservoir-monitoring tools involving modified-Hall and rate-transient analyses led to a comprehensive understanding of disposal-well performance. This study found a relationship of fracture gradient with limiting cumulative injection volume and identified key variables affecting the disposal-well behavior. These findings led to a smart and safe disposal-well monitoring scheme, which will help disposal-well management become more economic and environmentally friendly.

This paper is the third in a series of environmental risk assessments covering hydraulic fracturing (SPE 152596) and well construction (SPE 166142). Risk assessment and well failure from SPE literature and governmental agencies have been used to construct a detailed but non-company associated study of plug and abandonment (P&A) objectives, problems, best practices, application details and methods. The objective is to identify technology improvements as well as potential or proven problem areas. Technology gaps will be related where they are identified by either problem reports or failures. Case histories have been captured that illustrate a variety of abandonment reasons and approaches in plug setting, isolation and testing/monitoring methods. The study well groupings are divided by age and era or vintage of abandonment to examine the worth of technologies in force at the time of abandonment. Well age, well type and general geographic influences are presented with notation of specific problems and conditions that challenged effective isolation. Special attention will be paid to cases of failed isolation as cited by the governmental inspection and/or governing body as well as repair methods that restore integrity. Attention will also be given to problems encountered in older wells. Lessons gleaned from this study will be of value to well construction and operational maintenance with consideration paid to well type, geological hazards, production history and durability of the isolation seal.

This project presents results from one part of the Disappearing Roads (DR), a multi-year project to design, test and evaluate multiple temporary and permanent road materials for use in harsh environmentally sensitive areas. DR is a critical component of the joint industry project Environmentally Friendly Drilling Program (EFD). The DR project included a nationwide University competition sponsored by Halliburton to come up with potential designs as well as actual field trials of commercially available products, while the goal of the RPSEA sponsored portion of the project was to field test some of the products and designs identified in this competition. The specific objectives of the RPSEA Project are: Identify new technology that can reduce or eliminate the impact of drilling operations on environmentally sensitive areas. Design an EFD system using most promising technology Include environmental stakeholders in the designs After drilling operations are completed or suspended, roads are often remediated. This removal is intended to allow the recovery of the lands to a pre-use condition so as to minimize additional access. Experience has shown that such efforts pose difficulty, highlighting the complexity of potential long-term consequences of oil and gas operations. New systems have been tested to avoid this expense. Tests have been performed in a desert environment in West Texas as well as a second test located in a moderate climate with significantly more rain to determine the optimum operational conditions for the materials used. The project evolved to include roads made from recycled well cutting, plastic composite mats and mats made from waste materials. As in all projects the viability of any method is measured by the cost and benefit relationship. If the road material reduces cost either for construction or in the case of remediation and disposal of cuttings it could be considered a success.

Waste management shall be done comprehensively, starts from waste generator to final disposal. Waste management should base on Reduce, Reuse, Recycle, Recovery, and Disposal (4R+1D) principles. A good waste data management will enable us to promote waste management improvement based on these principles. Waste management data consist of waste recording, waste tracking, and waste reporting. In Total E&P Indonesie, every waste that generate by every entity in each production sites and drilling rigs will be recorded in waste register/Log book. Waste from every site will be transferred to final disposal (senipah) via transit area (handil). Every waste that transfers will be recorded and attached with Waste Transfer Note (WTN) form. Both of this recording system is a paper based systems and has several disadvantages. First, when compiling the waste data from waste register and waste transfer note, there is discrepancy of waste quantity between both of record systems. Second, it needs a lot of man hour to compile the waste data from both recording systems and human error is most likely happen here because of manually recapitulation of waste data which will directly affect the waste data that submitted to authority. Third, it is very hard to track the waste position when transferred, whether it has already arrived in transit area or final disposal because the control paper (Green parts of waste transfer note (WTN) form) often does not come back to waste generator. Total E&P Indonesie developed an application which aim to replace the waste register and waste transfer note and also solving the entire problem that caused by previous systems. This application is an integrated system of waste register, waste tracking, and waste reporting. This application called WISEMan. It has a lot of benefit. First benefit is waste recording, tracking, and reporting will need a short time which can minimize man hours. Second benefit is waste engineer in Total E&P Indonesie can focus on Improving Waste Management that refer to Reduce, Reuse, Recycle, Recovery, and Disposal (4R+1D) Principles, and third benefit is improving awareness of waste segregation to all personnel in TEPI premises because the WISEMan system makes the employee compulsory to segregate the waste that generate by each entity.

Environmental regulations for oil and gas companies have become increasingly stringent with particular focus on remote areas and environmentally sensitive terrestrial and marine locations and the preservation of natural habitats and resources. With this in mind, many regulatory agencies have adopted "zero discharge" policies requiring monitored disposal of all wastes generated from drilling operations. For designated drilling operations, the various waste streams include: drill cuttings, excess drilling fluid, contaminated rainwater, produced water, scale, produced sand, and even production and cleanup waste. Traditional practices range from onsite pit burial to temporary box storage and hauling of the waste products to a final disposal site. Environmental risks from accidental releases and gas emissions result in higher operating costs and present concerns and liabilities as disposal sites are often several kilometers (km) from the generation source. Cuttings re-injection (CRI) is a safe and cost-effective alternative that provides permanent and contained disposal of drilling cuttings in an engineering-determined subsurface formation. CRI provides a reliable method for achieving "zero discharge" by injecting slurrified cuttings and associated fluids into hydraulically created fractures up to several thousand meters below the surface. This disposal technique helps mitigate environmental risks and future liabilities associated with potential surface contamination. This paper outlines the first successful application of CRI technology in the offshore areas of Saudi Arabia as a cost-effective and environmentally friendly waste management technique. Details of CRI theory as well as best practices, challenges and lessons learned are presented in detail from initial engineering design to case study utilization. This high pressure CRI work was the first of its kind in the MENA region.

Fresh water and affordable energy are two of the most valuable resources on the planet for sustaining economic growth and development. As the demand for oil and gas continues to increase, the fresh water consumption rate by exploration and production (E&P) activities is skyrocketing. Competition for fresh water is threatening to become an industry-limiting factor in some oil and gas plays. To ensure that the fresh water needed by the oil and gas industry is available in the future, better water resource management practices must be developed and implemented. Currently, the drilling, completion, and stimulation of each horizontal shale well consumes up to 10 million gallons (gal) of fresh water, roughly equal to daily indoor water usage of 125,000 people [ U.S. Department of the Interior March 2010 ]. Once fresh water becomes oilfield waste, the water is typically disposed of into reservoirs below the fresh water table, permanently removing it from the fresh water cycle. Reusing the water is desirable but often presents technical problems with water quality, water management logistics, and cost. To help address these problems, a Forward Osmosis (FO) water reclamation process has been adapted for the oil and gas industry. The first generation of the process reclaims drilling waste water by converting it into high quality base fluid for hydraulic fracturing. In contrast to other water treatment systems, like reverse osmosis and evaporation, FO is a unique nano-filtration technology that harnesses the potential energy in a brine water solution as the drive mechanism, thus making the technology extremely "green" and cost competitive. Unlike conventional filtration to remove solids, the FO membrane rejects all solids and virtually all solutes from the reclaimed water, thus yielding a nano-pure water that will not react adversely with fracturing chemicals or the reservoir. The results of laboratory and field testing from early commercial jobs show that FO is a viable technology for the reclamation of drilling waste for beneficial reuse as a high quality completion fluid. The results also show that FO can help significantly reduce both the carbon footprint and water footprint of the oil and gas industry.

Abstract The oil and gas industry of today requires a social license to operate. As positive public perception diminishes, it demands that the industry adapt to a higher standard of operation to reduce its environmental footprint. There are systems that make it easy to achieve this and are able to fit on any rig, anywhere in the world. Drilling fluid losses total on average more than 5000 gallons per single well. Industry adaptation in Canada is 98% in directing the discharge of fluid during connections. Surprisingly, only 12% of Canadian drilling rigs have systems in place to capture and recycle directed fluid, even though drilling operators can drastically reduce mud costs and remediation expenses by capturing, and recycling fluid before it hits the ground. Common perception is that environmental stewardship and greenhouse gas reduction involves a prohibitive price tag, a misconception this paper will dispel. This paper illustrates the adverse effects of non-containment, introduces proactive technology available and presents several case studies demonstrating benefits of zero spill systems from a financial and environmental perspective. Widespread implementation of zero spill technology is crucial in elevating environmental stewardship, regaining a strong social license and improving profitability during capricious times in the market.

ABSTRACT An environmental scorecard is being developed to determine the tradeoffs associated with implementing low impact drilling technology in environmentally sensitive areas. The scorecard will assess drilling operations and technologies with respect to air, site, water and biodiversity issues. Low environmental impact operations will reduce the environmental footprint of operations by the adoption of new methods to use in (1) getting materials to and from the rig site (site access), (2) reducing the rig site area, (3) using alternative drilling rig power management systems, and (4) adopting waste management at the rig site. The scorecard enables a dialog to be established and maintained among all interested, concerned and affected stakeholders. In this manner, the oil and gas industry has a new way of seeing itself within the larger network. The scorecard presented in the paper provides the means to demonstrate the connectivity between energy production and the affected ecosystem. The Houston Advanced Research Center (HARC) and Texas A&M University have been leading an industry consortium effort to investigate the development of low impact drilling systems. The work originated in 2005 and funding was obtained by the U.S. Department of Energy for 2006 through 2008. The goal of the low impact drilling systems project is to reduce the environmental impact of rig operations through integration of low impact site access and site operations. The paper will discuss the scorecard that is being developed. The scorecard methodology presents an ecological understanding of the tradeoffs associated with producing energy. The EFD scorecard will be developed in detail for a coastal margin ecosystem and the methodology will be documented to enable the scorecard to be replicated at other ecosystems wherever reservoirs are produced. This scorecard methodology is being developed through a series of workshops being held with ecologists, botanists, wildlife management experts and others in addition to oil and gas industry experts. INTRODUCTION The Houston Advanced Research Center (HARC) and Texas A&M University through the Global Petroleum Research Institute (GPRI) have been collaborating with industry and environmental organizations to integrate and demonstrate current and new technology into land-based drilling systems for compatibility with environmentally sensitive or off-limits areas. The Environmentally Friendly Drilling Systems (EFD) Program is taking a systems approach to the integration of currently known but unproven or novel technology in order to develop drilling systems that will have very limited environmental impact and enable moderate to deep drilling and production operations and activity with reduced overall environmental impact. The EFD Program is identifying and providing the technology to successfully produce shale gas and tight gas sands while appropriately addressing environmentally sensitive issues. The project focuses on developing drilling technologies that can be used throughout the U.S., in particular, unconventional natural gas resources as illustrated in Figure 1 and Figure 2.

Abstract The Environmentally Friendly Drilling (EFD) program is taking a renewed look at dealing with the issue of waste management and re-use particularly with regards to produced water and water based drilling wastes, developing solutions that would possibly reduce the size of reserve pits needed in drilling operations and achieve significant waste volume reduction through the extraction of water from drilling wastes encouraging reuse of the extracted water in drilling operations and the concentration of suspended solids. The EFD is investigating the use of membrane-filtration technologies in the aforementioned aim of waste volume reduction and water extraction from drilling wastes. The investigation involves processing actual drilling wastes using various membrane types and configurations in developing solutions to challenges facing membranes particularly fouling. We are investigating the ability of these membranes to effectively remove the suspended solids from waste streams and refine the waste to levels where they could be used in drilling operations or sent for further treatment such as desalination. Our aim is to develop a mobile treatment unit made of a suitable membrane system that could be deployed to drilling sites to be used as an onsite option aimed at recycle or re-use of water resources. We are currently investigating in our laboratories various membrane-filtration technologies with water based oilfield wastes and coupling this with our prior development of field deployed technologies in developing a cost efficient membrane filtration system for field application. We show in this report how membranes have been used in the filtration of actual solids laden field supplied water based muds and a solids simulated laboratory water based mud, highlighting the compatibility of membrane systems with water based muds. In light of the evolving stringent regulatory standards and in demonstrating good stewardship of the environment, the Oil and Gas industry is expected to be active in reducing the footprint of its various activities on the environment and in showing optimal use of resources. This approach to dealing with drilling wastes confers the two-fold advantage of optimal use of water resources through re-cycle and the reduction of the footprint of drilling operations well within reasonable economic costs by saving significant waste treatment, hauling and freshwater costs. Introduction The energy question is increasingly becoming the most important question of this present age, with growing populations especially those of South East Asia and the attendant energy demand of these teeming population the issue of energy has become a pressing issue globally. The search for energy to meet present demands and future forecasts is becoming more intense and more diversified than ever, despite this diversification of sources to meet the energy demand globally, crude oil remains the prime energy source today and probably in the foreseeable future. This increased demand for energy and rising energy prices have renewed interest in unconventional oil resources as unconventional resources are estimated to play a major role in providing energy for the future(1). Parallel to increasing energy demand is the increasing awareness about environmental issues especially as they pertain to E&P operations. The last decade has witnessed increasing environmental regulation imposed by federal, state and municipal authorities on the industry in other to protect environments where exploration activities occur particularly during drilling.

Abstract The regulatory regime applicable to the onshore discharge of aqueous waste streams generated by Exploration and Production (E&P) facilities differs from the one(s) applicable to offshore discharges. The example of the European Union framework Directives shows the importance given to the characteristics of the receiving environment when regulating onshore discharges, while offshore, the regulatory regime, led by international (MARPOL) or regional conventions (such as OSPAR or the Kuwait Convention), primarily focuses on the source of the aqueous discharges. Today, offshore regulations are a compromise between aspirational goals and practicalities, as the recent development of interpretation of MARPOL rules regarding FPSOs and FSUs shows. The second part of the paper describes the basic principles developed by TOTAL to elaborate a realistic and sustainable position when regulations fail to provide sufficient guidance. Key widely accepted international conventions serve as a basis for internal standards while provisions of the regional conventions guide us when elaborating local standards for a specific installation, together with due consideration to the actual or forecast impact of aqueous discharges to the environment. Introduction Exploration and Production (E&P) facilities generates several aqueous waste streams which are to be disposed of by various means and according to current applicable laws. Most countries have developed regulations and standards which limit the amount of contaminants discharged into the environment, therefore protecting nature and human health. Each country having developed its own set of rules, requiring ad hoc technical solutions, it is challenging for international E&P companies which have assets all around the world - such as Total - to develop a unified policy and coherent technological responses, when designing or operating the facilities. There are many different receiving environments. A parallel can be established between the multiplicity of the regulations and the multiplicity and the wide range of the environments in which discharges occur: underground water layers (as long as they are not appropriate as a resource for human use); rivers of any size, from small to large; lakes; estuaries; coral reefs; coastal waters; lagoons, offshore open sea (a not-so-well known environment), and so on. A complex regulatory regime It is easy to understand that regulators wish to differentiate such various cases. As a result, several sets of texts are needed to regulate aqueous discharges where a single set of texts is enough to regulate emissions to the air. States usually regulate offshore and onshore discharges on a different basis: onshore discharges are usually regulated by the local state, while in many cases, there is no state regulation of the offshore discharges, except in developed countries where the offshore E&P activity exists for years (North Sea, Gulf of Mexico, etc.). Where no regulation has been written by a country to address its offshore aqueous discharges, reference has to be searched in international conventions. Most maritime areas of the world are covered by one or several such international conventions. But to be applicable to a country, any international convention or treaty must have been formally ratified by that country. And there are still some countries which have not ratified any of these conventions and where there is therefore no legal constraint on the aqueous discharges. On the other hand, once a country has ratified a convention, its provisions become a key reference: provisions that the country must at least fulfil. Discharges in surface waters (rivers, lakes, coastal waters). In most countries, including emerging countries which often derive their regulations from the ones implemented in the US, regulations related to aqueous discharges in surface waters set maximum values to the quantity of a limited number of contaminants which can be released in the surface waters. The list of these contaminants, and the maximum values depend on the type of industry, and there are significant differences from a country to another.

Abstract The river basin that empties into the Atlantic Ocean near the Brazilian city of Aracaju is the most important in the northeast corner of this environmentally sensitive country. The river basin supplies water for Aracaju's 470,000 inhabitants, as well as for many sugar cane plantations and cattle ranches in the region. Protecting that water supply was a major concern for Schlumberger operations based in Aracaju. The city's water is collected and treated from the Poxim River that flows close to the base. To ensure no contaminated water reaches the river, Schlumberger recently built an organically based wastewater treatment plant that has eliminated all sewage emissions. As a result of the new wastewater treatment plant, the Schlumberger base in Aracaju achieved the following results: Contributed to protection of local water supply Achieved significant reductions in harmful discharges Completely eliminated sewage emission into the Poxim River Received recognition from state environmental agency Eliminated odors and enhanced local vegetation In 2003, Schlumberger built a wetland tank to collect and treat effluent water from the base, which houses up to 120 employees. The new sanitation installation was built as a requirement to comply with local regulations, established in 2002, in order to renew the state environmental license for the base. The wetland tank replaced septic tanks that used to discharge used water into the Poxim River. The Aracaju Water Treatment Station collects its water from the river. Now, instead of being released into the river, effluent water is stored and re-oxygenated in a 37-cubic-meter cement treatment tank filled with coarse gravel in which Tabua plants live. The water treatment plant uses no mechanical devices. Rather aerobic and anaerobic chambers are used to degrade organic material. The final effluent water is evaporated in a wetland and any excess is used to irrigate grass and trees of the base. With this system, the treatment plant has achieved significant reductions in chemical oxygen demand, oxygen consumption and fecal coliforms. The discharge rates for these are significantly lower than those allowed by the new local environmental regulations. In addition the base has completely eliminated sewage emission into the Poxim River. The Schlumberger base was recognized by the state environmental agency that inspected the new plant in July/2004 to issue the environmental license. The agency took photographs and requested that plant be copied at other industrial installations at Sergipe State as part of environmental licenses locations. Also, the base's neighbor, a state finance agency, congratulated the base on the elimination of foul odors. Visually, the grass at the base entrance now is continuously green. 1. Introduction The new Sanitation Installations was a requirement to become compliant with local regulation in order to renew the State Environmental License (ADEMA). In the past, the Sanitation used were septic tanks discharging direct at Rio Poxim that has it water collected by Aracaju Water Treatment Station. With this new system using Aerobic and Anaerobic chambers, the final effluents is only water that is used to gardening. For Federal Environmental Licenses (required for offshore operation or discharge in river that cross another state) the requirements exist since 1986. For State EnvironmentalLicense, which is the SLB case, the legal requirements were established in 2002. The parameters were: COD = 300 mg/l (chemical oxygen demand) OC = 90 mg/l (Oxygen Consumption) Fecal coli forms = 2 × 105 1.1 Statement of Theory and Definitions With this new system using Aerobic and Anaerobic chambers, the final effluent water is evaporated in a wetland and any excess is used to irrigate the grass and trees of the base.

Abstract BP's recent exploration success in Angola is expected to result in a number of significant subsea developments in water depths ranging from 1200metres to in excess of 2000metres. Our understanding of the environmental impact of discharges associated with drilling and completions operations in deepwater Angola is immature at scale. Studies around single wells have been presented (Reference 1) but this type of work has not been considered for the development of a portfolio of subsea projects. A strategy and implementation plan has been developed by a multidisciplinary team to better understand the extent/impact of discharges and evaluate currently available and future waste management options, incorporating lessons learned from more mature deepwater operating areas where appropriate. This will enable informed decisions to be made on future implementation of best practicable waste management solutions. Introduction BP operates in two deepwater blocks offshore Angola, Blocks 18 and 31, and has an interest in non-operated Blocks 15 and 17 (Figure 1). Both development drilling on Greater Plutonio in Block 18 (which commenced in 2005) and exploration and appraisal drilling in Block 31 is ongoing. Both rigs currently in operation are drilling with synthetic oil based drilling fluid and using cuttings dryers down stream of the shale shakers to reduce the fluid content of the cuttings prior to discharge to the sea. This is a similar approach to other deep water operating areas for the operator in the Gulf of Mexico and Brazil. Before start up of development drilling operations on Greater Plutonio, an exhaustive study looking at best practices for managing discharges of "oily cuttings" was commissioned prior to arriving at the dryer solution. At the time the decision to use cuttings dryers was taken, legislation in country was under development and did not stipulate limits on oily cuttings discharges.

Abstract The increasing environmental legislation surrounding drilling operations has led to a rapid rise in drilling waste management spending by operators.The traditional perception has been that this increased spending adds to well construction costs.While it true that new technology comes with a price tag, and much of the technology used in drilling waste management has been introduced in the last 10 years, many technologies now available to operators are clearly cost effective when the entire well construction cost is evaluated. The cost of making a mistake and having either an expensive remediation project or a potential liability nearly always significantly outweighs the cost of a good preventative drilling waste management program.Further, compliance with current environmental regulations does not always guarantee immunity in the future. The correct deployment of both new and traditional drilling waste management technologies is reviewed in several case histories taken from the global operations of a major service company. The paper demonstrates that the correct application of these technologies combined with a holistic approach to drilling waste management and drilling fluid operations results in a net reduction in well construction costs and a reduction in the potential for environmental liability. Introduction Drilling waste has traditonally been defined as drill cuttings and excess drilling fluid1 and these certainly comprisethe vast majority of drilling waste.Other materials generated by drilling operations can include contaminated water, material and chemical packaging, emissions such as carbon dioxide, scrap metals, fuel, lubricants and other oils as well as the usual human and industrial wastes associated with any camp or offshore facility. For the purposes of this paper the focus will be on drill cuttings and excess or spent drilling fluids and the treatment and or disposal of these waste products at the end of the well or wells in compliance with the governing regulations for the area of operations. All the costs associated with that treatment and disposal are usually considered as part of the overall well construction costs.Evidence from the representative case histories presented here demonstrates that correct waste management and the right technology applications can actually reduce, rather than increase well construction costs. The reasons for this are explored in the paper. Timeline of Drilling Waste Management Up until the 1980s there was little or no drilling waste management as we know it today.The excess cuttings and fluid were typically discharged overboard in offshore operations and spread on the lease sites or buried in land operations.At this time there was generally little, if any, legislation regarding the disposal of these materials.Discharge and landspreading were low cost solutions that also allowed the operator to remain in compliance with existing regulations.Therefore the the actual of amount of waste generated and was subsequently disposed of was of little consequence or interest to the operator or service company. In fact it was argued it was detrimental to the service company to reduce the amount of fluid and waste generated as these volumes were the primary method of compensation. In the 1980s and early 1990 global awareness and understanding of environmental issues was significantly increased. The impact of drilling operations and in particular drilling waste became a subject of interest to operators, service companies and regulators.The early regulations typically restricted what could be disposed of by setting limits on oil content or chloride content or the location of proposed disposal sites in reference to the water table and local environment, etc.The types of fluids being used also came under closer scrutiny and the toxicity of fluids and cuttings was evaluated and regulated.\

Abstract This paper describes the development, validation, and application of a numerical model that simulates solids injection operations for soft rock reservoirs. There exist many classical fracturing models that are good tools for evaluating solids injection operations in formations with competent rocks. However, when evaluating solids injection operations in soft rock formations such as unconsolidated sand, these classical fracturing models generally fail to provide reliable evaluations. In this paper, a solids injection model was specifically formulated and developed for solids injection in soft rock formations. The development of the proposed model for soft rock formations is based on the Biot's self-consistent theory, plasticity theory, and fracturing and liquefaction criteria for rock. The predictive capability of the developed model was verified against field data from waste injection wells in soft rock formations. The validated model was used to evaluate solid waste disposal for cases of various injection operation conditions in a soft rock reservoir. Results show that the solids injection model provides an effective tool to assess the maximum injection volume allowed per well, the area of influence of injection, the bottom-hole injection pressure, and the vertical containment of the injected fluids and solids. Simulation results for representative cases are presented. The model can also be useful for quantitatively assist in identifying feasible solids injection mechanisms in soft rock reservoirs. Introduction In general, a solids injection model can be a useful tool for waste disposal operations to estimate the maximum injection volume allowed, the area of influence, the injection pressure, and to evaluate the containment of the solids storage zone in the target formation. There exist many classical fracture models that are good tools for evaluating solids injection operations in formations with competent rocks. However, when evaluating solids injection operations in formations with soft rocks such as unconsolidated sand, these classical fracture models generally fail to provide reliable evaluations. 1,2 Thus, there is a need to specifically develop a solids injection model for solid waste disposal in soft rock formations. The objectives of this paper were twofold. First, a solids injection model for soft rock reservoirs was developed to simulate solids injection operations with a single disposal well. The development of the proposed solids injection model for soft rock formations is along the lines of Biot's self-consistent theory, plasticity theory, and fracturing and liquefaction criteria for rock. To make the model a simple and practical tool for field applications, the proposed model only retains primary physics of rock failure and coupled rock deformation and fluid flow. The model does not include the effects of well configuration and completion, wellbore storage, and any other complicated physics such as development of wormholes. Second, injection evaluations of solid waste disposal were conducted by using the developed model for cases of various injection operating conditions. In the following sections, we present the details of the proposed model that include coupled field equations, constitutive relations, and numerical procedures. Then, the model was verified for its ability of retaining primary physics by field operation data. Using the validated model, a simulation study was conducted and results from the study were evaluated in detail. These results include the maximum injection volume allowed per well, the area of influence of injection, the bottomhole injection pressure, and the vertical containment of the injected fluids and solids. Finally, concluding remarks are made based on this work. The Solids Injection Model In this study, a 3-dimensional, nonlinear solids injection model was specifically developed for soft reservoir rocks to simulate solids injection into a weak formation. The developed model has the capability to predict bottomhole injection pressures, the safe maximum slurry injection volume, and the area of influence under various injection-operating conditions. In the following, a detailed description of the model is presented.

Abstract The need for paying close attention to the environment has been of paramount important since the introduction of specific environmental legislation (for example the Environmental Management Act 3/2000) in Trinidad and Tobago. Out of the Environmental Management Act, several pieces of legislation have been drafted to better regulate the industry and include: Environmentally Sensitive Areas and Species Rules Noise Pollution Rules Certificate of environmental Clearance Rules Air Pollution Rules (Draft) Water Pollution Rules (Draft) The only shortcoming is that there are presently no solid and hazardous waste management rules in Trinidad, and the Environmental Management Authority is currently in the process of planning for the development of the rules for the entire country and by extension, the petroleum industry as a whole. The approach to date has been the focus on a simple piece of legislation to govern all industrial sectors. While this may be an approach to the management of common types of wastes encountered in all industrial sectors, it may not be practical for the petroleum industry. Developing a model and testing it against practical data for the petroleum industry can only be the practical way the legislation would be meaningful to the industry. Introduction In Trinidad, the need for a more care and attention to the environment is urgently needed. Although the Environmental Management Act 3/2000 has become law with the need for a Certificate of Environmental Clearance before any new plant can be built, there is still no urgency to move the requirements forward. Attempts are being made to move the legislation forward. The paper undertaken examines the development of a model and evaluating it against the generation of hazardous waste in an area serviced by several facilities and industries. St Patrick County, located at the south-west peninsula (see Figure 1) of Trinidad was chosen to carry out a feasibility study in developing a landfill to handle hazardous waste. In this county there are several industries that co-exist and the amount of waste generated need to be disposed of properly. The information derived from the area would be used to test the model being proposed. Hazardous wastes are substances intended for disposal, recycling, or recovery that can harm people, plants, animals, or the environment. Properties of Hazardous Waste Waste is hazardous and a recyclable is a hazardous recyclable waste if, when tested: it has a flash point of less than 61°C, it ignites and propagates combustion in a test sample, it contributes oxygen for combustion at a rate that is equal to or greater than that provided by ammonium persulphate, potassium perchlorate or potassium bromate, it is toxic because it has an oral toxicity LD50 not greater than 5000 mg/kg, has a dermal toxicity LD50 not greater than 1000 mg/kg, or has an inhalation toxicity LC50 not greater than 10,000 mg/m3 at normal atmospheric pressure, it has a pH value less than 2.0 or greater than 12.5, it contains polychlorinated biphenyls at a concentration equal to or greater than 50 mg/kg, or it is a toxic leachate because it is in a dispersible form and it contains any of the following substances in a concentration greater than 0.001 mg/L: hexachloro-dibenzo-p-dioxins, pentachloro-dibenzo-p-dioxins, tetrachloro-dibenzo-p-dioxins, hexachloro-dibenzofurans, pentachloro-dibenzofurans, tetrachloro-dibenzofura

Abstract The Ameriven Central Waste Treatment Facilities (CTRD Centro de Tratamiento y Recuperación de Desechos ), which were designed and implemented with the technical support of teams provided by a major drilling waste management service company, receives and processes heavy-oil drilling and production waste generated by operations in the Hamaca Project, located in the Faja Region of the Orinoco Belt in Venezuela. The CTRD operational strategy emphasizes the 4Rs: reduction, reuse, recovery, and recycling. Important cost savings have been achieved from: the consolidation of waste treatment at one location near the source; and the efficient waste management practices implemented by the fluids and waste management team, under contract with Petrolera Ameriven (Ameriven). The facility now serves as a model for similar operations in the region and has earned unconditional approval from governmental agencies and prominent companies with commercial interests in the area's forests and resources. Over the life of the 30-year project, the facility will process the waste from approximately 250 to 500 wells. The current development production phase yields 80,000 bbl/day, with 190,000 bbl/day extra-heavy crude expected in the commercial production phase. Cost reductions related to waste management and disposal at this site are currently estimated at 22% (since commencement of operations) and are expected to improve further as the facility is used to full capacity. Several integrated processes are implemented for the efficient disposal of drilling waste products: thorough rig audits, solids-control equipment performance, rig, field, and plant supervision, dewatering, water treatment, and landfarming and landspreading of processed solids and cuttings. Introduction The Ameriven Central Waste Treatment Facilities (CTRD Centro de Tratamiento y Recuperación de Desechos ) were installed in 2002 to process heavy-oil drilling and production waste generated by operations in the Hamaca Project, located in the Faja Region of the Orinoco Belt in Venezuela ( Fig. 1 ). Over the life of the 30-year project, the facility will process waste from 250 to 500 wells. The current development production phase yields 80,000 bbl/day, with 190,000 bbl/day extra-heavy crude expected in the commercial production phase. The CTRD operational strategy emphasizes the 4Rs: reduction, reuse, recovery, and recycling. Important cost savings have been achieved from: the consolidation of waste treatment at one location near the source; and the efficient waste management practices implemented by the fluids and waste management team, which is under contract with Petrolera Ameriven (Ameriven). The facility now serves as a model for similar operations in the region and has earned unqualified approval from governmental agencies and prominent companies with commercial interests in the area's forests and resources. Since the CTRD project startup, the overall cost of drilling fluid and waste management has dropped 36%. At the time of this writing, 109,088 bbl of crude oil, valued at over U.S. $1million, have been returned to the Central Operating Base (COB). Before the CTRD was installed, the volume of crude oil would have required disposal at an extremely high cost ( Fig. 2 ). Achieving the 4Rs The CTRD facility has processed the waste from 87 wells at the time of writing. Both drilling and production waste streams have been processed. The drilling waste stream comprises cuttings, drilling fluid, oil contamination in the drilling fluid, cement, and spacers. The production waste stream comprises completion fluids, oily sludge from tanks, equipment, and pipelines, and contaminated soils resulting from any spill situations that may occur.

Abstract Obtaining funding for the purchase of existing facilities can be daunting, particularly, if the seller has not maintained adequate records. This paper presents a troubled case history of the transfer of assets, where the seller did not conduct adequate due diligence during the previous transfer and could not satisfy the prospective buyer's lender request for proof of previous disposal of solid waste. In addition, the paper offers recommendations for avoiding data acquisition problem. Small operators must obtain financing for the acquisition of existing facilities to enhance their market share. With the strenuous environmental regulations existing in the United States, lenders are reluctant to provide funds unless the purchaser/seller can provide proof of a clean facility and environmental compliance with existing regulations. No proof of a clean facility and compliance, no funds are made available! Most technical papers considering acquisitions concentrate on evaluating oil and gas reserves payout or property value. These issues are important, but even with the best economic situation; a lender is hesitant to loan funds for a purchase having an environmental "cloud" or non-compliance issues. The recommendations contained in this paper are based on an actual acquisition almost stopped in its tracks by a Resource Conservation and Recovery Act question. Introduction In years past, the by-words were "caveat emptor" (let the buyer beware). This situation is changing as the result of lender's reluctance to loan money, if environmental problems might haunt the property and compromise loan repayment. Today, all industrial properties considered for acquisition require a Phase I site assessment (ASTM, 2000) and most likely, a Phase II site assessment (ASTM, 2001). The need for a Phase III assessment is seldom involved in acquisition or divestiture of industrial property, because, if the property must be remediated, the property is not consider worthy of purchase. Phase I Assessment Property acquisition/divestiture commences with a Phase I visual site and record assessment (ASTM, 2000). ASTM E-1527, Phase I site assessment, is Comprehensive Environmental Response, Compensation and Liability Act [CERCLA) driven. This means the assessor concentrates on the surface and sub-surface condition of the property based on observations and records. Even here E-1527–00 is deficient, e.g., Does not define Environmental Professional -the document only provides guidelines; Environmental Professional not obligated to identify mistakes in recorded data; Environmental Professional not required to investigate environmental problem outside of the Phase I process preview, e.g., regulatory compliance Does not require consideration of adjoining property problems; Confusion between "Recognized Environmental Condition (REC) and de minimis condition; Unfortunately, these deficiencies of ASTM E 1527–00 leave the buyer and seller with "business environmental risks" (ESA, 2001a and b). Lenders do not like business risks. This leads to loans being withheld on the basis of the Phase I assessment. Phase II Assessment Phase II site assessment concentrates on sampling and analyses of surface/subsurface soils and waters based on the results of the Phase I assessment, e.g., Select sampling sites Design and install monitoring wells Identify, record and preserve the samples Transport the samples to the laboratory under a Chain of Custody form Request analytical methods for the appropriate contaminants Analyze the laboratory results against an acceptable concentration standard. All of the above issues are important and the Phase II ASTM document E1903–01 provides guidance for all these issues except an "acceptable concentration standard".

Abstract In April 1998, a program for continuous deep disposal of drill cuttings and open pit materials was initiated on the North Slope of Alaska. This ongoing injection project is commonly referred to as GNI, standing for Grind and Inject. Accumulated drilling cuttings and mud slurry is injected into a receptive cretaceous soft sandstone in three wells, GNI-1, GNI-2, and GNI-3. Typical operations involve injecting slurry into one of the three wells continuously for a number of days and then switching injection to another well. The average injection rate is approximately 30,000 barrels per day. As of September 30, 2002, project injection has included 12.7×10 6 barrels of water, 30.9×10 6 barrels of slurry containing 2.0×10 6 tons or 2.2×10 6 cubic yards of excavated frozen reserve pit material and drilling solids and 1.31×10 6 barrels of fluid from ongoing drilling operations. Knowledge of the fate of the drilling and open pit materials during injection is paramount to assure the safe sequestration of the materials without harm to the environment. Numerical modeling, well testing (including step rate and pressure falloff testing) as well as logging surveys were performed periodically to assess the disposal wells' operational integrity and to ensure the safe containment of the disposed waste slurry. The great capacity of these injectors highlighted the mechanisms for slurry being accepted by multiple and branched fractures - part of the slurry went to previous fractures during subsequent batch injections. The current paper will emphasize on how to integrate numerical simulations, well testing/monitoring and operational data to estimate storage capacity and to construct a clear representation of what was happening underground during this grind and injection operation. The work has implications on other large drilling waste injection projects worldwide. Introduction Early drill sites on the North Slope of Alaska were designed with reserve pits for surface storage of mud and cuttings from drilling operations. In 1993, ARCO agreed to remove the mud and cuttings from all reserve pits. Additionally, ARCO and BP discontinued the practice of storing drilling mud and cuttings in surface reserve pits. These waste streams are now managed as they are generated by way of injection, eliminating the need for surface reserve pits. The estimated total volume of reserve pit mud and cuttings to be managed by this process is over 5 million cubic yards (not including drilling mud and cuttings generated from ongoing drilling operations). After reviewing disposal options, slurry injection was selected as the preferred disposal technique to remediate the reserve pits. Drill cuttings injection projects have been operated worldwide since early 1990s. 1–5 However, these projects were generally small in volume. Feasibility evaluation of large scale injection of oily waste injection in Alaska started in late 1980s. 1 This field evaluation test also included a step-rate test, in-situ stress measurements, tilt-meter monitoring of ground surface deflections and a wellbore hydraulic impedance test. 1 Approximately 2 million barrels of slurry, containing crude oil, unused frac sands, drilling muds, unset cement and others, had been injected intermittently into this well at the time of the analysis. The injection rate varied from 500 bpd to 4,000 bpd. The first large scale slurry injection project for the reserve pit closure started in March 1995 on the North Slope of Alaska. A total of 8 million barrels of slurry were injected into this well (well DS 4–19) over two years at approximately 30,000 bpd. 6 Injected slurry contained a total of 413,000 cubic yards or 340,00 tons of excavated frozen mud and drill cuttings. This project demonstrated that Grind and Injection (GNI) is an environmentally safe and cost effective method for disposing the mud and drill cuttings resulted from pit closure on the North Slope of Alaska. It should be noted that the terms of DCI (Drill Cuttings Injection) and GNI are used interchangeably throughout this paper.