Invention of Wheel – A Historical Revolution for Science and Civilisation

ABSTRACT

The process of capturing Carbon Dioxide (CO2) from a source that is Stationary ( Power Station may be) , to transport the processed product ( Using a Pipeline may be) and finally to inject it a suitable place ( a Geological formation) is known as Geo Sequestration of CO2. The project under taken mainly focuses on the various process and each stage explanation of understanding how the CO2 can be captured from any source. All kinds of issues and problems that may incur and hinder the process at any stage in developing this product. CO2 once obtained needs to be stored and transported to the subject site where it can be injected for long time. While undertaking all this process there are many risks and issues that may occur in completing this process. All the risks regarding this are identified and are managed in all possible ways using Risk Management procedures. All the project management techniques are identified and discussed in details using all various tools and mechanisms. One of the most suitable ways and technique of project management is to use and follow PMBOK technique.

Using the project management technique to the complete sequestration process and consolidating it as a complete project is discussed in detail and managed as a complete project. All the cost and risks involved in this complete procedure are discussed and taken into account in order to evolve it as a whole some project. All the various project management techniques and ways are considered and applied to the project. The Green House impact is discussed in detail with all its possible processes. All the various types of gases emitted are discussed with all possible ways to control and reduce it.

The Green House gases are extremely injurious to health and may have various dangerous effects oh lungs, skins and physically as well. CO2 as a complete project is a laborious task and involves tedious mechanisms which needs to be undertaken with great care, consideration, and applied and  CO2 sequestration geologically and projects related to it most of the times have several multiple criteria’s and issues to finish it successfully for all the stake holders.

Introduction

Geo Sequestration involves the capture of Carbon Di oxide ( CO2) using any source that is stationary such as any power station source and further transportation using any means such as a pipeline so that it can be injected into a suitable site such as a geological formation. There are several other terms that may be used for sequestration such as Carbon Capture Storage (CSS) or Carbon or Carbon Di oxide Capture and Geological Storage (CCGS) and Carbon Capture and its Geological Sequestration ad Geological Disposal. However, we can conclude that there is no universal word or nomenclature that we can used for Sequestration. The term “Storage” is usually preferred in European Nomenclature. Whereas the storage has the connotation with CO2 that can retrived at some stage , how ever as a matter of fact there is unlikely or technically oreconomically not possible and technically not feasible in almost all the circumstances to retrieve it . The term Storage hwoever doest not encompass the storage from ocean in which the CO2 is stored in deep inside water column of any ocean )  as the geological storage. The term Geological Sequestration is getting increasingly popular in USA  . However , the used term of Geo Sequestration has been taken to incorpaorate the CO2 Capture , Transport and Geologically storing it .

Figure below shows the complete process

There are several reasons because of which the Ocean Storage can not be considered for the Ocean storage. At times it becomes out of scope for many reasons . Furthermore the used technology is immature and probably it is not at a position where it is ready for application. In addition to it there are serious and obvious reasons in which the oceans storage remains an environmentally feasible mitigation option , which may lead to ultimate solidification of the subject ocean with clear negative impact on Marine Fauna . However, the deep geological CO2 storage may be under taken deep under the ocean sea floor , that doesn’t mean that it is ocean storage , since the injected CO2 is not expected to enter even the ocean , it always locks away under the floor of ocean.

However it is important to note that since there are various geological storage sites which are known to occur offshore , which occur under the shelf of continental shelf which may include the Australian Continental Shelf.

Moving on further , the chemical reaction of CO2 with purely finely grounded mineral of rocks such as alumina silicates indicates an advanced storage known as mineral storage. Having many similarities with Geo Sequestration, it may be under taken as a full surface chemical process. While being examined on various occasions , it is not seen and considered as a viable economic option . Mineral Storage how ever is not considered here at all.

Background

Over a last decade there has been a constant concern regarding the increased atmospheric amound and content of Carbon Di oxide (CO2) and other gases emitted because of Green House effect. All these gases have a very serious impact on climate of earth and is growing significantly over the period of time .

There many countries of the world including United states that are fighting to bring in a balance between economic development and meeting a near ending term goals where as to minimize the long term risks related to environment. In process of finding a solution to these grave problems specially the build up of Green House Gases in the Atmosphere, a study conducted and pursued by the United States Department of Energy (DOE) the National Energy Technology Laboratory with its partners related to academics , the sequestration of Carbon Dioxide has been a prime solution to almost all problems related to Green House impact. In this process a permanent storage of CO2 emissions in geological underground formation has been evolved which ultimately avoids CO2 to release in atmosphere and reacting with different gases to produce various harmful by products.

In order to cater for the emissions of Green House Gases particularly fossil fuels fired power plants , the Carbon dioxide sequestration always proves to be one of the most feasible and suitable option. In this process the mechanism is evolved in order to capture the subjected Carbon Dioxide , transport it to the sequestrated site and to inject it multilaterally to the geological formation. Whereas , the process of CO2 sequestrations in geological formations can never be achieved significantly in reducing the Green House Gases emissions till the time it not acceptable to the concerned regulators , the stake holders and the general public that involves that the risks involved are judged to the acceptable limit .

In order to achieve this , there is one tool that can be used to get the acceptance to geological sequestration of CO2 , that is known as Risk Assessment of complete process. Risk assessment has proved itself to manage the hazards objectively the hazardous effects of facilities such as the oil and natural gas fields , the refineries, the used pipelines and different chemical plants in use. In order to cater for the CO2 Sequestration the Probabilistic Risk Assessment (PRA) which has been applied in many other areas has proved itself infancy for this sequestration . .

What are the Issues of Geo-sequestration

The Geo Sequestration of Carbon Dioxide always remains a tedious and complex task. The whole procedure involves a complete chain of events. Starting from the capture of carbon dioxide , its storage , transporting it to the subject poses various problems at different stages. The final stage of injecting it to the suitable formation is the most critical step and always involves a thorough site considerations, suitable temperature conditions and a complex mechanism overall.   The burning of Coal , gas and Oil under standard and suitable circumstances produces the Carbon Dioxide Gas. According to most of the scientists the most largest contributor to Green House effect is Carbon Dioxide which always traps heat that is coming from the Sun in the atmosphere of earth. This causes change in climate. Other gases such as methane , nitro, chlorofluorocarbons (CFCs), Chlorofluorocarbons and and the Sulphur Hexadecimal also adds in to the problem .

Problem Caused by Geo- sequestration

Report Organization

The report regarding Geo Sequestration of Carbon Dioxide will be oraginzed in way that will involve a complete description of this Sequestration Process. The Green House Effect and its impact in atmosphere will be discussed. The greenhouse gases emitted with its various hazards will be considered in detail. The relation between Geo Sequestration and its use to cater for and to reduce the Green House Gases will be discussed in detail. The whole process is taken as a complete project and after discussing in depth all techniques of project management , the PMBOK procedure will be used to manage the complete project. There are various risks involved in managing this project , the complete Risk Management procedure will be used to manage the things in a suitable manner.

Literature Review

1.      The Perennial vegetation in terrestrial carbon sequestration:

In the terrestrial sequestration using the perennial vegetation is the most vital element. It role in the ecosystem dynamics is very known to all. Due to the industrial and technological advancement that has been achieved by the human society with time, the paradoxical related to vegetation has undergone the degradation and destruction in the modern times. Due to this advancement there has been observed a significant emission in Carbon Dioxide as a whole. Therefore, it is an hour of need to deal with this environmental menace that is a constant source of hazard and danger of environment. Carbon Dioxide are produced mostly by the trees since 50 % of their overall standing mass is carbon itself. The importance of carbon sequestration in forested area is well accepted and documented. Similar to frosted tress, the needle leaf vegetation and green fruit trees also have same sequestration of CO2. The most alarming part is that there is no attempt that is made to study and to classify the area that is based to see the quantity of CO2 that is sequester.  Study has been carried out to predict Carbon Sequestration using the cashew and Carina plantation of Tamil Nadu that is used to remote sense and use ecosystem modelling.

1. The Terrestrial Carbon Sequestration potential in India:

According to one of the estimate , the standing biomass in India was equal to 8376 meter in the year 1985, and the storage is expected tone 4280 meter. The carbon that is stored in the forests that includes soil as well , estimates to about 9570 meters. Whereas, the emissions of carbon from the fossil fuels based on energy production and its related consumption activates in India amounts to about 150- 230 meter annually. The estimates given by different scientists and ecologists vary quite differently from each and other. Agricultural activates that includes burning of fuel ranges from 40 to 120 meters . The present rate of reforestation is being balanced by the current emission of carbon by the agricultural industry and forestry sectors . As  a result of it , the entire fossil fuel industry remains unabated. According to one of the estimates , in various areas in area , the experiments regarding sequestration of carbon proved to be successful and were proved to be successful in the tears to come . These experiments paved a new way towards development and much greater progress.

Greenhouse Effects

The Earths climate is powered by Sun in which the radiations from sun are emitted at very short wavelengths. The spectrum that is produced remains visible or nearly visible that is Ultraviolet rays being the part of Spectrum . According to one of the studies being carried out , nearly one third of the solar energy in the form of rays that reaches the earths atmosphere top, is reflected back to space. Where as the remaining the third portion remains absorbed by the surface and up to a lesser extent is absorbed by the atmosphere.  In order to balance out this phenomenon as a whole, as a general principle, the Earth in turn must also radiate the same amount of energy back into the space. Since the Earth in comparison is much more colder than the sun , it radiates much more longer wavelengths , that are in particular in infra red spectrum . The radiations emitter by the Land and ocean are the thermal radiations that may also include clouds and they are therefore re-radiated backwards towards the Earth. The process involved as a whole is known as Green House Effect. In the Green House , the glass wall helps to reduce the airflow and ultimately increases the temperature of the whole air inside. The average temperature at the surface of earth remains below the freezing point of water , without the natural greenhouse effect .

The possibility if life on the planet earth is possible because of Earths Natural Green house effect . However, the activates of human beings on earth because an ever going increase in industrial revolution and the burning of the fossil fuels that involves almost every step , have immensely increased and intensifier the naturally occurring green house effects and is contributing significantly towards the most commonly known phenomenon of Global Warming. As far as atmosphere is concerned , the most abundant gases that are present in atmosphere are Nitrogen (making 78 % of dry atmosphere ) and oxygen that ( makes almost 21 %) of gases exerts nearly no green house effect. The molecules that are a  bit more complex and are less common , instead, comes from the Green house effect. The vapours of Water remains the most significant content and carbon diode remains on the second most important greens house gas. Nitro-us oxide , the Methane gas and many other gases that are present in atmosphere in very small amount also contributes towards the Green house effect.

Greenhouse Gases

Carbon dioxide

Using Flask measurements located at Mauna Lua Laboratory in Hawaii , in 1958 , a very high quality concentrations of CO2 began and started with a new discovery. In the experiments carried out it was clearly visible that annual content concentration of CO2 present in atmosphere raised to an amount from 320 ppmv (parts per million of volume ) in 1959 to round about 345 ppmv in 1998. In the Northern Hemisphere , It has been observed to have a clear annual cycle in Mauna Loa Dara which corresponded to an annual cycle plant of respiration in the Hemisphere of Northern Region. The content of CO2 concentration always increased in the Fall and Winter and after wards declined during the season of summer and Spring. In the Southern Hemisphere , however, the complete cycle followed the growth and its through die back of vegetation, and it then disappeared completely in data measurement near the Equator.

Methane

Over the last complete decade, the rate of increase in abundance of methane has been at the declining end , and became more significant dramatically from 1990 to 1993 , however it showed an apparent increase in the growth rate particularly in late 1995. As a whole , the average trend from 1981 to 1991 was about 14 ppbv/year ( parts per billion by volume /year)

Nitrous oxide

The average growth rate over the last almost 4 decades was about 0.27 % per year. The troposphere concentration of Nitrous Oxide NO2 was about 316 to 218 ppbv.

Fluoridated gases

In industrial applications , the family of man made gases are commonly known as Fluoridated Gases. Their major use is as an Ozone Depleting Substances since they ever damage the ozone layer present in atmosphere. Hence , the F- gases have proved to be very powerful green house gases , with global warming up to 24000 times greater than Carbon Dioxide. However, their emissions are increasing rapidly.

Greenhouse Gases Emissions

The Green house gases emitted are already discussed in the above section . All these gases have adverse effect on atmosphere and its effect is increasing at a dramatic rate which is ultimately contributing towards a complete catastrophic situation . The gases emitted particularly because of burning of various types of fossil fuels remains a very dangerous concern. Furthermore , due to a continuous advancement in technology the use of Chlorofluorocarbons have been significantly increased which is now creating a complete menace for not only humanity but in particular the major portion of population living in urban areas.

Emissions Causes and Sources

The greenhouse gases such as methane are produced by carrying out agricultural practices such as manure management of livestock that remains a prime concern because of an ever growing increase in population and to cater for day to any human needs. Other gases such as Carbon Dioxde , CO2, comes for the natural process of respiration and furthermore from the fossils fuel like oil, gas and coal burning which remains a necessity of an ever growing industrial growth as a whole . 70 percent of the electricity produced in United states of america comes from Sulphur Oxide emissions which shows the hazardous effect it has on environment. In addition to it the electricity production also includes about 13 % of nitrogen oxide emissions  and 45 percent of Carbon Dioxide emissions that comes from natural atmosphere.

One of the other major cause is the cutting of trees and bigger plants that are use to produce heat or various wood related products, they release the carbon dioxide that is stored in all such products during the process of photosynthesis. According to the Global Forest Resource recent Assessment, there has been a nearly billion ton production of carbon because of various reasons and causes.

According to the research undertaken by EPA ,it has been observed that the gases emitted by green house effect , can offset the effect when a forestation practice is carried out at a large scale. The Replication of tress at a large scale helps to increase and build up the Carbon Dioxide content in atmosphere , as it is growing and the tress semester the carbon dioxide through the process of photosynthesis. The Atmospheric carbon dioxide is first of all converted , and then stored in vegetation and other soil formations of any forest. Furthermore it has been observed that , the forests being created cannot alone sequester the Carbon Dioxide that is emitted to the atmosphere by the burning of the fossil fuels and ultimately a reduction in emission of the gasses is still very vital and necessary to avoid its major build up in the complete atmosphere.

The output of Green house effect gases is a prime and grave concern now a days throughout the whole world. With  a very rapid increase in industrialization from the year in particular from 2009 , the level of Carbon Dioxide have been increased to almost 40 percent and the production of methane have been increased dramatically to the amount of about 139 #%. According to the research department, NASA, the major portion of increase has been due in the past 50 years of world history . After 1998, because of the menace of Global Warming , the year of 2014, was recorded as the most warmest year of the world and furthermore the 10 most hottest years have come after 1997.

“The warming we observe affects atmospheric circulation, which impacts rainfall patterns globally. This will lead to big environmental changes, and challenges, for people all across the globe,” Josef Werne, an associate professor in the department of geology and planetary science at the University of Pittsburgh, told Live Science.

According to the scientists and various researchers , it has been found that, the worst effects of global warming may have the worst effects ever that may include

1. Extreme in weather conditions
2. A sudden rise in sea level
3. Extinction of plants and Animals
4. Acidificaion of oceans
5. Major shifts in climate
6. Unprecedented upheaval in society

Burning of fossil fuel

The Burning of fossil fuels remains a prime concern in the rapid increase in gases that emitted in the atmosphere because of green house effect. There are various gases that are emitted because of this forces out of which the CO2 is the most significant of all . The hazardous effects and impact of Carbon Dioxide remains a prime concern and need serious efforts to resolve it like using the technique of Geo sequestration of CO2.

Deforestation

A research published by the Duke University it has been observed and proved through various experiments under taken that the second cause of CO2 release is the deforestation that is increasing significant through out the world due to an ever increase in not only population but a rapidly increasing industry growth as well .

One of the other major cause is the cutting of trees and bigger plants that are use to produce heat or various wood related products, they relase the carbon dioxide that is stored in all such products during the process of photosynthesis. According to the Global Forest Resource recent Assessment, there has been a nearly billion ton production of carbon because of various reasons and causes.

Over population

Because of an ever growing increase in population there has been an abrupt development in all types of industries and a sudden shift from rural to urban areas. The population increase is the root cause of all problems . A lot of serious efforts needs to be done on this issue so that we can not only control the over population but also most of the problems that may occur due to this menace to entire humanity .

Agriculture and farming landfills

With the sudden increase in population , there has been a gradual increase in agricultural development and production . The world is facing problems because of shortage of the agricultural products. The various process involved in agricultural growth and landfills of farming lands are the major contributor towards this grave hazard.

Greenhouse Gases Impact on Biodiversity

Climate Change

The relation ship between the change in climate the impact of Green house gases is well known  . All the gas emitted because of various reasons contribute significantly towards a major change in climate and may impact the human life in a very harmful manner. Efforts done in order to reduce the impact of greenhouse effect seems useless. The various dangerous hazards caused by this phenomenon remains a grave concern of all scientists and efforts are made to control the temperature as much as possible .

Threats to Biodiversity

The effect of green houses gases is very imminent to biodiversity . The various gasses emitted due to this process are extremely dangerous for bio diversity . The impact is not only dangerous but diverse as well . It encompasses all biological products that are dealt under this dimension.

Temperature Spikes

The abrupt change in climate remains a concern for the human beings living on the globe. Because of green house effect there has been a visible spike in temperature in all dimensions. The various gases emitted from burning of fossil fuels and cutting of trees remains a prime source and concern which as a whole plays a very vital part in causing temperature variation making human life uncomfortable on planet earth.

Changes in Rainfall

Moreover, this meanness of Green houses gases have also effected the trends in rainfall . There has been a visible change in amount of rainfall through the world and the researchers and scientists have proved through studies and experiments that the major roles has been played by the greenhouses gases emitted because if an ever increasing industrial growth and development.

Rise in sea level

It has been observed throughout the in addition to various other problems posed in , the rise of sea level remains a great concern. It is not increasing the land covered by the sea water but also adds in to death tolls every year because of its hazardous impact on whole man kind.

Greenhouse Gases Health Issues

The worst effects of global warming are numerous in nature and huge in danger. Its impact on globe, human life , plant life and on animals is quite obvious and visible . Moreover, the predicted impact of global warming on human life and environment remains varied and very grave in nature. It is considered that It is difficult to attribute specifically any natural phenomena for a ling term in order to solve issues related to health being caused by global warming . It is an hour of need to analyze this problem seriously to solve this menace to humanity .

Skin Diseases

Heart and Lung Diseases

Infectious Diseases

Water and Food Quality

As the climate warms, it changes the nature of global rainfall, evaporation, snow, stream flow and other factors that affect water supply and quality. Freshwater resources are highly sensitive to variations in weather and climate. Climate change is projected to affect water availability. In areas where the amount of water in rivers and streams depends on snow melting, warmer temperatures increase the fraction of precipitation falling as rain rather than as snow, causing the annual spring peak in water runoff to occur earlier in the year. This can lead to an increased likelihood of winter flooding and reduced late summer river flows. Rising sea levels cause saltwater to enter into fresh underground water and freshwater streams. This reduces the amount of freshwater available for drinking and farming. Warmer water temperatures also affect water quality and accelerate water pollution

Food scarcity is a major key for many populations and is one of the prominent concerns with the changing climate. Currently, 1/6 of the global population are without adequate food supply.^[69] By 2050, the global population is projected to reach 9 billion requiring global food productions to increase by 50% to meet population demand.

Greenhouses Gases Reduction Method

What is Geo-sequestration of CO₂

CO₂ Capture and Storage

Current short-, medium- and long-term projections for global energy demand still point to fossil fuels being combustive in quantities incompatible with levels required to stabilise greenhouse gas (GHG) concentrations at safe levels in the atmosphere.

All technologies along the CCS chain are known. They have been in operation in various industries for decades, although at relatively small scale. However, for the sole purpose of limiting climate change, these technologies have been put together in industrial scale (>1Mt CO₂ captured and stored per year) in only a small number of installations.

Process of Geo-sequestration

The process of capturing and storing carbon dioxide from major industrial and energy-related sources (such as power stations) underground. Another term for geosequestration is Carbon Capture and Storage (CCS). In a typical geosequestration process, carbon dioxide (CO2) is captured at an industrial facility, compressed and transported by pipeline to a suitable storage location. There, it is injected into a deep geological formation beneath the Earth’s surface where it is intended that the CO2 will be stored in isolation from the atmosphere for a very long time.

CO₂ Capturing

The starting point for geosequestration is storage of relatively pure CO2. In a few instances, industrial processes emit fairly pure CO2 and that CO2 can be captured and separated relatively cheaply. Such processes include the manufacture of some fertilizers and natural gas processing. The latter is especially significant because it provides a relatively pure stream of CO2 at little additional incremental cost. The reason for this is that CO2 must be separated from methane to meet sales gas specifications. It is also for this reason that some of the earliest geosequestration projects are based on natural gas activities (Sleipner in Norway; In Salah in Algeria). In Australia the Gorgon LNG project is currently planned to be the first large scale commercial geosequestration project in Australia.

The issue of separation of CO2 from natural gas is likely to be significant to Australia in the future, as approximately half of our identified natural gas resources have high concentrations of CO2. This means virtually all natural gas used for liquefied natural gas (LNG) will need to have the CO2 removed. Domestic gas sales have higher sales gas specifications for CO2, but in many cases in the future will still have unacceptable CO2 concentrations. Therefore, as natural gas production increases so will the amount of pure CO2 separated at the production facility. For these reasons, natural gas processing is a potential “early mover” in the application of geosequestration in Australia.

CO₂ Transportation

Unless the source of separated CO2 lies directly above or adjacent to a site for injection, it is necessary to transport the CO2 to the injection site, usually by pipeline (Figure 1). In this case, the CO2 is compressed to a dense fluid prior to transport, and water (and possibly some contaminants) will be removed. The pipeline transport of CO2 is a well understood and practiced activity. In the USA, for example, there are several thousand kilometres of CO2 pipelines, used to transport CO2 for use in enhanced oil recovery. In Australia, transport by pipeline is accepted, and widely used for natural gas. Therefore, pipeline transport of CO2 in Australia is likely to be acceptable to the community.

Transport by road or rail may be technically feasible for small scale projects but is likely to be prohibitively expensive. Transport by ship may be feasible in some circumstances. At the present time there is at least one European vessel dedicated to the transport of high purity CO2 for food processing. In the same way that LNG is transported around the world it would be technically feasible to transport large quantities of CO2 from a coastal emission source to an offshore storage site. The costs of such a scheme are likely to be high; nonetheless it cannot be completely dismissed and may represent an option for the future. However for the foreseeable future, transport of CO2 by pipeline is the most practical and economic option.

The issue of transport does have potential implications to the future siting of power stations. At the present time, siting of a power station depends on factors such as the market for the electricity, the source of the fossil fuel (usually coal), the location of cooling water and the planning regime. In the future, consideration will also have to be given to the location of a potential geosequestration site. Indeed it would be prudent for all future power stations in Australia to be sited with full consideration being given to future geosequestration options.

CO₂ Injection

CO2 injection was completed over a 16-day period, beginning on March 10, 2009, and ending on March 26, 2009. The impacts of various injection pressures and temperatures on the CO2 injection rate were investigated. The overall approach consisted of an initial injection of CO2 at the maximum allowable pressure of

CO₂ Storage

Prior to storage, the emitted gas stream is concentrated to 95% or more of CO2 and compressed to a dense super critical fluid – a liquid which has a density (depending on the pressure) of around 0.5 -0.7 grams/cc (water has a density of 1gm/cc). Provided the CO2 is injected to a depth of 800 m or more, it will remain in this dense form, which means that far more CO2 can be stored than if it were to be injected in a gaseous state.

The storage of CO2 involves keeping the CO2 secured deep underground in an appropriate geological formation. The main geological conditions for this include a porous and permeable reservoir rock, a trap, and an impermeable caprock. Expertise in locating such geological formations is well established within the oil and gas industry, and geoscientists and engineers utilise mature technology to identify and evaluate specifi c sites for their geosequestration potential. Each site is evaluated for its potential storage volume as well as to ensure that conditions for safe and effective long-term storage are present.

Since the injected CO2 is less dense than the formation water, it will slowly rise to the top of the geological reservoir, and a geological trap is needed to ensure that it does not escape and reach the surface or potable groundwater. The most common traps found in Australia are structural (e.g. an anticline), stratigraphic (“pinchout” of a reservoir rock) or hydrodynamic (CO2 entrained in the formation water). An overlying impermeable top seal is required to keep the CO2 within the storage formation. Such seals are generally very fi ne grained rocks with low porosity and low permeability. The seal must be of sufficient thickness to prevent microfractures and through-going faults from developing as possible CO2 leakage pathways.

Depleted oil and natural gas fields, which generally have proven geologic traps, reservoirs and seals are potentially excellent sites for storage of injected CO2.  In some circumstances it may be possible to combine geological storage of CO2 with enhanced oil recovery or enhanced gas recovery. This has not been carried out to date in Australia but is an area of research for CO2CRC because of the potential to beneficially combine geosequestration with increased production of hydrocarbons. CSIRO, the University of Queensland and CO2CRC are also undertaking reseacrh into the use of CO2 storage to enhance the production of coal bed methane. When injecting into a depleted fi eld care must be taken that all existing well-bores are adequately cemented before sequestration operations begin, to ensure that there is no leakage of CO2 from old wells.

Techniques of Project Management Method

What is Project

Nearly every activity within an organization could be labelled as a project possessing unique characteristics and varying levels of importance to the organization. A project is defined as a planned undertaking of related activities to reach an objective that has a beginning and an end.[16] All projects solve some type of problem, but projects may also be established simply to determine and define feasible alternative solutions to problems. Seven primary characteristics of a project include:[11]

1. Objective: Each has a specific goal to reach.
2. Schedule: Point in time in which they must be accomplished.
3. Complexity: Does the technology exist to achieve the project objectives?
4. Size and Nature of Task: Step-by-step plan of action.
5. Resources: Labor, personnel, equipment, materials, facilities, etc.
6. Organizational Structure: The ‘meshing’ of project requirements into the existing organization.
7. Information and Control Systems: These must be structured to handle problems through the typical lines of authority (Prin. of Project Mgmt)

What is Project Management

In the past, a company typically decided to undertake a project effort, assigned the project and the “necessary” resources to a carefully selected individual and assumed they were using some form of project management. Organizational implications were of little importance. Although the basic concepts of project management are simple, applying these concepts to an existing organization is not. Richard P. Olsen, in his article “Can Project Management Be Defined?” defined project management as “…the application of a collection of tools and techniques…to direct the use of diverse resources toward the accomplishment of a unique, complex, one-time task within time, cost, and quality constraints. Each task requires a particular mix of these tools and techniques structured to fit the task environment and life cycle (from conception to completion) of the task.” [11]

Employing project management technologies minimizes the disruption of routine business activities in many cases by placing under a single command all of the skills, technologies, and resources needed to realize the project. The skills required depend on each specific project and the resources available at that time. The greater the amount of adjustments a parent organization must make to fulfill project objectives, the greater chance exists for project failure. The form of project management will be unique for every project endeavor and will change throughout the project.[11]

The project management process typically includes four key phases: initiating the project, planning the project, executing the project, and closing the project.

Project Management Process

Initiating the Project
The project management techniques related to the project initiation phase include: [16]

1.      Establishing the project initiation team. This involves organizing team members to assist in carrying out the project initiation activities.

2.      Establishing a relationship with the customer. The understanding of your customer’s organization will foster a stronger relationship between the two of you.

3.      Establishing the project initiation plan. Defines the activities required to organize the team while working to define the goals and scope of the project.

4.      Establishing management procedures. Concerned with developing team communication and reporting procedures, job assignments and roles, project change procedure, and how project funding and billing will be handled.

5.      Establishing the project management environment and workbook. Focuses on the collection and organization of the tools that you will use while managing the project.

Planning the Project
The project management techniques related to the project planning phase include:[16]

1.      Describing project scope, alternatives, and feasibility. The understanding of the content and complexity of the project. Some relevant questions that should be answered include:

o    What problem/opportunity does the project address?

o    What results are to be achieved?

o    What needs to be done?

o    How will success be measured?

o    How will we know when we are finished?

2.      Divide the project into tasks. This technique is also known as the work breakdown structure. This step is done to ensure an easy progression between tasks.

3.      Estimating resources and creating a resource plan. This helps to gather and arrange resources in the most effective manner.

4.      Developing a preliminary schedule. In this step, you are to assign time estimates to each activity in the work breakdown structure. From here, you will be able to create the target start and end dates for the project.

5.      Developing a communication plan. The idea here is to outline the communication procedures between management, team members, and the customer.

6.      Determining project standards and procedures. The specification of how various deliverables are produced and tested by the project team.

7.      Identifying and assessing risk. The goal here is to identify potential sources of risk and the consequences of those risks.

8.      Creating a preliminary budget. The budget should summarize the planned expenses and revenues related to the project.

9.      Developing a statement of work. This document will list the work to be done and the expected outcome of the project.

10.  Setting a baseline project plan. This should provide an estimate of the project’s tasks and resource requirements.

Executing the Project
The project management techniques related to the project execution phase include:[16]

1.      Executing the baseline project plan. The job of the project manager is to initiate the execution of project activities, acquire and assign resources, orient and train new team members, keep the project on schedule, and assure the quality of project deliverables.

2.      Monitoring project progress against the baseline project plan. Using Gantt and PERT charts, which will be discussed in detail further on in this paper, can assist the project manager in doing this.

3.      Managing changes to the baseline project plan.

4.      Maintaining the project workbook. Maintaining complete records of all project events is necessary. The project workbook is the primary source of information for producing all project reports.

5.      Communicating the project status. This means that the entire project plan should be shard with the entire project team and any revisions to the plan should be communicated to all interested parties so that everyone understands how the plan is evolving.

Closing Down the Project
The project management techniques related to the project close-down phase include:[16]

1.      Closing down the project. In this stage, it is important to notify all interested parties of the completion of the project. Also, all project documentation and records should be finalized so that the final review of the project can be conducted.

2.      Conducting post project reviews. This is done to determine the strengths and weaknesses of project deliverables, the processes used to create them, and the project management process.

3.      Closing the customer contract. The final activity is to ensure that all contractual terms of the project have been met.

What is Project Management Methodology

Project management is the discipline of initiating, planning, executing, controlling, and closing the work of a team to achieve specific goals and meet specific success criteria. A project is a temporary endeavor designed to produce a unique product, service or result with a defined beginning and end (usually time-constrained, and often constrained by funding or deliverables) undertaken to meet unique goals and objectives, typically to bring about beneficial change or added value.^[1][2] The temporary nature of projects stands in contrast with business as usual (or operations),^[3] which are repetitive, permanent, or semi-permanent functional activities to produce products or services. In practice, the management of these two systems is often quite different, and as such requires the development of distinct technical skills and management strategies.^[4]

The primary challenge of project management is to achieve all of the project goals within the given constraints.^[5] This information is usually described in a user or project manual, which is created at the beginning of the development process. The primary constraints are scope, time, quality and budget.^[6] The secondary — and more ambitious — challenge is to optimize the allocation of necessary inputs and integrate them to meet pre-defined objectives.

Types of Project Management

Following are the most frequently used project management methodologies in the project management practice:

1 – Adaptive Project Framework

In this methodology, the project scope is a variable. Additionally, the time and the cost are constants for the project. Therefore, during the project execution, the project scope is adjusted in order to get the maximum business value from the project.

2 – Agile Software Development

Agile software development methodology is for a project that needs extreme agility in requirements. The key features of agile are its short-termed delivery cycles (sprints), agile requirements, dynamic team culture, less restrictive project control and emphasis on real-time communication.

3 – Crystal Methods

In crystal method, the project processes are given a low priority. Instead of the processes, this method focuses more on team communication, team member skills, people and interaction. Crystal methods come under agile category.

4 – Dynamic Systems Development Model (DSDM)

This is the successor of Rapid Application Development (RAD) methodology. This is also a subset of agile software development methodology and boasts about the training and documents support this methodology has. This method emphasizes more on the active user involvement during the project life cycle.

5 – Extreme Programming (XP)

Lowering the cost of requirement changes is the main objective of extreme programming. XP emphasizes on fine scale feedback, continuous process, shared understanding and programmer welfare. In XP, there is no detailed requirements specification or software architecture built.

6 – Feature Driven Development (FDD)

This methodology is more focused on simple and well-defined processes, short iterative and feature driven delivery cycles. All the planning and execution in this project type take place based on the features.

7 – Information Technology Infrastructure Library (ITIL)

This methodology is a collection of best practices in project management. ITIL covers a broad aspect of project management which starts from the organizational management level.

8 – Joint Application Development (JAD)

Involving the client from the early stages with the project tasks is emphasized by this methodology. The project team and the client hold JAD sessions collaboratively in order to get the contribution from the client. These JAD sessions take place during the entire project life cycle.

9 – Lean Development (LD)

Lean development focuses on developing change-tolerance software. In this method, satisfying the customer comes as the highest priority. The team is motivated to provide the highest value for the money paid by the customer.

10 – PRINCE2

PRINCE2 takes a process-based approach to project management. This methodology is based on eight high-level processes.

11 – Rapid Application Development (RAD)

This methodology focuses on developing products faster with higher quality. When it comes to gathering requirements, it uses the workshop method. Prototyping is used for getting clear requirements and re-use the software components to accelerate the development timelines.

In this method, all types of internal communications are considered informal.

12 – Rational Unified Process (RUP)

RUP tries to capture all the positive aspects of modern software development methodologies and offer them in one package. This is one of the first project management methodologies that suggested an iterative approach to software development.

13 – Scrum

This is an agile methodology. The main goal of this methodology is to improve team productivity dramatically by removing every possible burden. Scrum projects are managed by a Scrum master.

14 – Spiral

Spiral methodology is the extended waterfall model with prototyping. This method is used instead of using the waterfall model for large projects.

15 – Systems Development Life Cycle (SDLC)

This is a conceptual model used in software development projects. In this method, there is a possibility of combining two or more project management methodologies for the best outcome. SDLC also heavily emphasizes on the use of documentation and has strict guidelines on it.

16 – Waterfall (Traditional)

This is the legacy model for software development projects. This methodology has been in practice for decades before the new methodologies were introduced. In this model, development lifecycle has fixed phases and linear timelines. This model is not capable of addressing the challenges in the modern software development domain.

Sequential Methodology

In a sequential methodology, informally known as the waterfall, the analysis phase comes first, then the design phase, followed by the implementation phase, and finally by the testing phase. The team that does each phase may be different, and there may be a management decision point at each phase transition.

PMBOK Methodology

While it may be debatable whether this is a true project management methodology, you will find organizations that say they use the PMI or PMBOK method for managing projects. What this simply means is they break down their projects into the five process groups agreed upon by the Project Management Institute (PMI) and documented in the Guide to the Project Management Body of Knowledge (PMBOK), namely: initiating, planning, executing, controlling, and closing.

Project management purists however insist that PMBOK is not so much a methodology as it is an agreed upon set of standards and conventions for managing projects. A similar analogy is that the dictionary is not a method for creating books, but it collects the agreed-upon vocabulary used to write books.

The Change Management Methodology

There are the methodologies that deal with managing projects but with an extra focus on change management especially planning for risks and taking control of change when it happens. Notable methods include:

+ Event Chain Methodology (ECM)

The underlying idea behind event chain methodology is that there are potential risks that often lie outside the project’s scope. It’s important to prepare for these risks and plan what to do if they occur. Why? Unexpected events will impact your project’s schedule, deliverables, and potentially its success.

+ Extreme Project Management (XPM)

Extreme project management (XPM) is the opposite of Waterfall in that it offers you a way to manage massive change and still move forward to project completion. In XPM, you can alter the project plan, budget, and even the final deliverable to fit changing needs, no matter where the project is. It’s the perfect way to manage projects that have a short timeline of anywhere from a few weeks to mere days.

PDCA Methodology

PDCA (plan–do–check–act or plan–do–check–adjust) is an iterative four-step management method used in business for the control and continual improvement of processes and products. It is also known as the Demingcircle/cycle/wheel, Shewhartcycle,control circle/cycle, or plan–do–study–act (PDSA). Another version of this PDCA cycle is OPDCA. The added “O” stands for observation or as some versions say “Grasp the current condition.” This emphasis on observation and current condition has currency with Lean manufacturing/Toyota Production System literature.^[1]

PLAN

Establish the objectives and processes necessary to deliver results in accordance with the expected output (the target or goals). By establishing output expectations, the completeness and accuracy of the specification is also a part of the targeted improvement. When possible start on a small scale to test possible effects.

DO

Implement the plan, execute the process, make the product. Collect data for charting and analysis in the following “CHECK” and “ACT” steps.

CHECK

Study the actual results (measured and collected in “DO” above) and compare against the expected results (targets or goals from the “PLAN”) to ascertain any differences. Look for deviation in implementation from the plan and also look for the appropriateness and completeness of the plan to enable the execution, i.e., “Do”. Charting data can make this much easier to see trends over several PDCA cycles and in order to convert the collected data into information. Information is what you need for the next step “ACT”.

ACT

If the CHECK shows that the PLAN that was implemented in DO is an improvement to the prior standard (baseline), then that becomes the new standard (baseline) for how the organization should ACT going forward (new standards are enACTed).

Risks Involved in CO₂ Geo-sequestration

Environmental Risks

Carbon dioxide is part of the atmosphere we breathe and is essential to all life forms. It is odourless and non-toxic. However, as it is denser than air, if it accumulates in low-lying areas in high concentrations then it can prove harmful to humans and animals.

The most substantial risk associated with CCS is the leakage of CO2 from storage sites. While there is some experience with geological storage of CO2 and natural gas for periods of approximately 10-20 years, long term storage over many hundreds or thousands of years

has not been proven.

However, as argued by CSIRO, the ongoing study of naturally occurring underground accumulations of CO2 has increased knowledge and confidence in the viability of CO2 storage.

The IPCC Special Report on CCS suggests that the environmental risks associated with CO2 capture and storage are low. As the IPCC stated: …well-selected geological formations are likely to retain over 99% of their storage over a period of 1,000 years. Overall, the risks of CO2 storage are comparable to the risks in similar existing industrial operations such as underground natural gas storage and [EOR].

Furthermore, according to many submissions, the safety, health and environmental risks associated with CCS are similar to, or less than, those already experienced in the oil and gas industry.21  5.25 Nevertheless, concerns have been expressed regarding the long term storage of CO2. Two types of CO2 leakage that may occur are: „ abrupt leakage through injection well failure or leakage up an abandoned well; and  „ gradual leakage, through undetected faults, fractures or wells.

Abrupt leakage

Abrupt or catastrophic leaks of CO2 could have serious consequences to the environment, potentially causing the death of humans and animals.23 Leakages have been known to occur naturally, such as at Lake Nyos in Cameroon in 1986.

There is the potential for CO2 that is sequestered as part of the CCS processes to leak from storage points. Such leakage could occur if the well seal at the point of storage failed thereby resulting in the release of sequestered CO2.  5.28 Evidence to the Committee from Greenpeace and the Australian Government also suggested that pressure built up by injected CO2 could trigger small seismic events.25 5.29 In his submission Dr Maddison also raised potential risks associated with CCS, stating that: carbon dioxide sequestration is poorly conceived, cannot guarantee sequestration of gas forever as is necessary and has potential for great harm due to accidental or deliberate release.26 5.30 It has been suggested that CO2 storage sites may become potential terrorist targets or that failure of the seal could result in catastrophic release. Greenpeace points out that concentration of CO2 greater than 7-10 per cent by volume in the air puts the lives and health of people in the vicinity in immediate danger.27 5.31 However, evidence suggests that if storage sites are carefully selected, the chances of a catastrophic leak would be minimal. Current demonstration projects, such as the Otway Demonstration Project, extend understanding of the scientific processes and risk minimisation associated with the selection, sequestration and monitoring of CO2 in an Australian context.

Gradual leakage 5.32 Gradual leakage could occur as a result of incorrect site selection and inadequate preparation.28 This leakage would compromise the initial objective of removing the CO2 from the atmosphere. 5.33 Other dangers associated with gradual leakage have also been highlighted. According to the International Association of Hydro-geologists, CCS is a potential environmental risk to overlying fresh groundwater resources and therefore CCS should only be considered in geological formations which are not potential groundwater resources i.e. aquifers which are not connected with active groundwater flow systems.29   5.34 In terms of assessing the probability of leakage and escape of CO2, Greenpeace points out that little is known about the behaviour of large quantities of CO2. Greenpeace suggests that, because of the complex geology of each individual storage site, evaluation can only be conducted on a case by case basis.  5.35 Greenpeace states that storing CO2 underground can dissolve the minerals that help stop the gas from escaping. The results from tests that injected CO2 into saline aquifers in Texas showed that sequestration made aquifer water more acidic. This acidity attacked the surrounding rock formations, causing them to dissolve and thereby potentially allowing the gas to leak into the water table.30  5.36 In his evidence, Dr Maddison expresses similar concerns regarding potential leakage. He contends that there may be problems associated with the use of depleted gas fields, including rocks cracking as gas is removed causing structural changes which may result in the rock structure no longer being able to hold their contents for long periods of time. Furthermore, problems also exist in association with the re-pressurising of rocks when injecting CO2 and the integrity of the well plug. Dr Maddison states that ‘there is no proof that once a field is filled with carbon dioxide, the plug can or will remain intact over the rest of time.’31

Risk Management

Rigorous risk mitigation strategies should be developed and implemented in order to reduce the risk of CO2 leakage. For example, in evidence to the Committee it was noted that the risks of leakage during pipeline transportation can be reduced if care is taken that the water content of the CO2 stream is kept low. This will avoid corrosion of the carbon manganese steel used in most pipe construction Greenpeace raised concerns about the relative lack of experience with CCS risk mitigation strategies and the need for long term monitoring techniques.33  5.39 The CSIRO states that proper regulation is necessary to ‘ensure that operators are competent, sites are appropriately chosen, and that wells are properly cemented.’34   5.40 CSIRO contends that catastrophic leakage is unlikely if sites are well selected, operators are competent and wells are properly sealed.35 Rigorous site selection, diligent monitoring and management of the injection site are all critical factors and it is important that these activities are appropriately regulated.36 Likewise, Chevron stated that ‘the most effective way to mitigate the risk of containment failure is through rigorous site selection and management of injection operations’

Project Management Selection

Consider a scenario in which the organization you are working for has been handed a number of project contracts. But due to resource constraints, the organization cannot take up all the projects at once. Therefore, a decision has to be made as to which project needs to be taken up to maximize profitability.

This is where Project Selection Methods come into play. There are various methods to help you choose a project. These can be divided into two categories, namely:

1. Benefit Measurement Methods
2. Constrained Optimization Methods

PMBOK Methodology

The Project Management Body of Knowledge collects set processes, best practices, terminologies, and guidelines that are accepted as standards within the project management industry.

Overview of PMBOK Methodology

The Project Management Body of Knowledge (PMBOK) covers nine elements of managing projects. These areas are:

• Project Integration Management
• Scope Management
• Time Management
• Cost Management
• Quality Management
• Human Resources Management
• Communications Management
• Risk Management
• Procurement Management

These nine areas are outlined with strategies on how to implement them.

·         Integration Management

Project integration management is a collection of processes that outline the project so that the venture is successful. Project integration management consists of seven steps:

1. Developing the project charter
2. Developing the preliminary project scope
3. Developing the project plan
4. Executing the project and producing deliverables
5. Monitoring the progress of the project
6. Integrating change controls in the project
7. Closing the project

·         Scope Management

Scope management deals with five processes meant to ensure that the project is self-contained and does not meander. The scope element section includes:

1. Information on writing the scope statement
2. Scope defining
3. Creating work breakdown structures
4. Verifying the scope
5. Controlling the scope

·         Time Management

A third element of project management PMBOK covers is time management. This element includes processes for:

• Defining activity
• Sequencing activity
• Estimating the duration of activities
• Estimating resource activities
• Developing schedules
• Controlling schedules

·         Cost Management

Cost management deals with resources and budgeting. Processes included under cost management consist of:

• Estimating costs
• Budgeting costs
• Controlling costs in a project

·         Quality Management

Quality management has to do with the deliverables of the project. The goal of project managment is to produce quality deliverables. Processes of quality management include planning quality, assuring quality, and controlling quality.

·         Human Resource Management

This element deals with all aspects of managing human resources, from resource planning to acquiring, developing, and managing the project team. Many articles on human resource management can be found on Bright Hub’s Project Management Channel including Gary’s “Employing Effective Resource Management at Your Company.”

·         Communication Management

Effective communication is very important during the project management process. This element of PMBOK deals with who needs to know what, when. Processes covered by communication management include:

• Communications planning
• Information distribution
• Reporting performance
• Stakeholder management

·         Risk Management

Risk Management is a crucial element of managing a successful project. Risk management processes in PMBOK literature include:

• Risk management planning
• Identification of risks
• Qualitative and quantitative risk analysis
• Planning risk response
• Risk monitoring and control

Bright Hub has a wealth of information on risk management in project management including Joe Taylor’s Risk Management Series.

·         Procurable Management

Managing Procurables is the final element of PMBOK project managing. This element includes six processes. These six processes are:

• Planning purchases
• Acquisitions
• Plan contracting
• Requesting responses from sellers
• Selecting sellers
• Administering contracts, and closing contracts

Project Evaluation Review Technique (PERT)

The Program Evaluation and Review Technique (PERT) is a widely used method for planning and coordinating large-scale projects. As Harold Kerzner explained in his book Project Management, “PERT is basically a management planning and control tool. It can be considered as a road map for a particular program or project in which all of the major elements (events) have been completely identified, together with their corresponding interrelations’¦. PERT charts are often constructed from back to front because, for many projects, the end date is fixed and the contractor has front-end flexibility.” A basic element of PERT-style planning is to identify critical activities on which others depend. The technique is often referred to as PERT/CPM, the CPM standing for “critical path method.”

PERT was developed during the 1950s through the efforts of the U.S. Navy and some of its contractors working on the Polaris missile project. Concerned about the growing nuclear arsenal of the Soviet Union, the U.S. government wanted to complete the Polaris project as quickly as possible. The Navy used PERT to coordinate the efforts of some 3,000 contractors involved with the project. Experts credited PERT with shortening the project duration by two years. Since then, all government contractors have been required to use PERT or a similar project analysis technique for all major government contracts.

Gantt Chart

A Gantt chart is a type of bar chart, devised by Henry Gantt in the 1910s, that illustrates a project schedule. Gantt charts illustrate the start and finish dates of the terminal elements and summary elements of a project. Terminal elements and summary elements comprise the work breakdown structure of the project. Modern Gantt charts also show the dependency (i.e., precedence network) relationships between activities. Gantt charts can be used to show current schedule status using percent-complete shadings and a vertical “TODAY” line as shown here.

Although now regarded as a common charting technique, Gantt charts were considered revolutionary when first introduced.^[1] This chart is also used in information technology to represent data that has been collected.

Planning

Scope

Time Frame

Resources

Implementation

Network Chart

What are Network Diagrams?

A Network Diagram is a visual representation of a project’s schedule. Well known complements to network diagrams include the PERT and Gantt charts. A network diagram in project management is useful for planning and tracking the project from beginning to finish. It represents a project’s critical path as well as the scope for the project.

A good network diagram will be a clear and concise graphic representation of a project.

S-Curve

“A display of cumulative costs, labor hours or other quantities plotted against time. The name derives from the S-like shape of the curve, flatter at the beginning and end and steeper in the middle, which is typical of most projects. The beginning represents a slow, deliberate but accelerating start, while the end represents a deceleration as the work runs out.”[1]

Types of S-curves

There are a variety of S-curves that are applicable to project management applications, including:

• Man Hours versus Time S-curve
• Costs versus Time S-curve
• Baseline S-curve
• Actual S-curve
• Target S-curve
• Value and Percentage S-curves

Applying Project Management for Geo-sequestration of CO₂

Project Management Risk Management

One tool that can be used to achieve acceptance of geologic sequestration of CO2 is risk assessment, which is a proven method to objectively manage hazards in facilities such as oil and natural gas fields, pipelines, refineries, and chemical plants.  Although probabilistic risk assessment (PRA) has been applied in many areas, its application to geologic CO2 sequestration is still in its infancy.

The most significant risk from geologic carbon sequestration is leakage of CO2. Two types of CO2 releases are possible— atmospheric and subsurface. High concentrations of CO2 caused by a release to the atmosphere would pose health risks to

humans and animals, and any leakage of CO2 back into the atmosphere negates the effort expended to sequester the CO2.  Subsurface risks, attributable to subsurface releases, arise from the displacement of fluids by the injected CO2 that could damage nearby hydrocarbon resources or trigger small seismic events. There is also the potential for sequestered CO2 to leak into non-saline formations, which could cause problems with potable uses of this water.  However, overall, risks from CO2 sequestration are believed to be small.

Implementation of CO2 sequestration is being approached in phases.  The DOE is currently sponsoring a series of pilot tests to generate important data that will elucidate the risks involved in geologic sequestration and lead to the development of risk management protocols. This phased approach should ensure that potential sources of leakage are identified, consequences are quantified, events with the potential to cause harm are analyzed to estimate their frequency and associated risk, and safeguards are put in place to further reduce risks for an operation for which risks already appear to be low.

Risk Assessment

Concern about increasing atmospheric concentrations of carbon dioxide (CO2) and other greenhouse gases (GHG) and the potential impact of these increases on the earth’s climate has grown significantly over the last decade.  Many countries, including the United States, wrestle with balancing economic development and meeting critical near-term environmental goals while minimizing long-term environmental risks.  One promising solution being pursued by the U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) and its industry and academic partners is carbon sequestration—a process of permanent storage of CO2 emissions in underground geologic formations, thus avoiding CO2 release into the atmosphere.  This option looks particularly attractive for point source emissions of GHGs, such as fossil fuel fired power plants.  In this case, CO2 would be captured, either pre- or post-combustion, compressed to a dense fluid, transported, most likely by pipeline, to a storage site, and sequestered in an appropriate geologic formation, such as a depleted oil or natural gas field, a saline formation, or an unmineable coal seam [1].

The most significant risk from geologic carbon sequestration is leakage of CO2. Two types of CO2 releases are possible— atmospheric and subsurface. These may be caused by slow leaks through slightly permeable cap rock or catastrophic releases due to rupture of a pipeline, failure of a field well, or opening of a fault. In general, CO2 is not classified as a toxic material; however, high concentrations of atmospheric releases pose health risks to humans and animals.  Additional risks are attributable to subsurface release of injected CO2. Although methodologies exist to estimate and report leakage from storage sites, further development is needed.

One tool that can be used to achieve acceptance of CO2 sequestration is risk assessment, an essential step in risk management. Risk management involves selecting appropriate prevention and control options, policies, and processes to manage risks.  Evaluating risk is a proven method to manage hazards objectively in facilities such as oil and natural gas fields, refineries, and chemical and pharmaceutical plants.  Although probabilistic risk assessment (PRA) has been applied in these areas, its application to geologic CO2 sequestration is still in its infancy.  A PRA evaluates both the likelihood and the impact of an unplanned event.  Use of PRAs allows decisions to be made on the most cost effective risk reduction and management options.

Prudent handling and management of CO2 are required to offset potential health hazards. Implementation of CO2 sequestration is being approached in a series of phases. This should ensure that potential sources of leakage are identified, consequences are quantified, events with the potential to cause harm are analyzed to estimate their frequency and associated risk, and safeguards are put in place to reduce risk to an acceptable level.

Risk Identification

As national policy makers, project developers, and investors begin to evaluate potential investment opportunities and technology options for undertaking emissions reduction activities, evaluation of the cost and overall environmental effectiveness of each technology option is necessary.  Moreover, any analysis of applicable technologies must take into account the siting, energy, resource, and policy constraints of the region, state, or city in question.  A critical component of this type of evaluation is assessing the risks associated with a particular technology and/or practice.  With geologic sequestration, risk assessment will primarily focus on the probability and consequences of CO2 leakage from a geologic storage site over time and the potentially adverse effects of this leakage on health, safety, the environment, and public policy. This paper addresses these questions.

Risk Analysis

Risk involves two factors—the probability (frequency) of a specified hazardous event and the severity of the consequences from that event.  Risk can be defined as the product of these two factors:

Risk = Frequency x Consequences

Thus, one can have the same level of risk for a frequent event with a low level of damage as for a rare event with a very high level of damage.  Therefore, in developing a risk assessment, one must evaluate both frequency and potential damage from an event.  Risk assessment can address public safety, employee safety, property damage, revenue loss, and environmental damage. This methodology, called probabilistic risk assessment (PRA), is the industry standard.

PRAs use probability distributions to characterize variability or uncertainty in risk estimates.  In a PRA, one or more variables in the risk equation are defined as probability distributions rather than as single values.  Similarly, the output of a PRA is a range or probability distribution of risks. Geologic storage of CO2 is well suited to analysis using PRAs because sequestration is a process-driven problem occurring over a long period of time.

Risk Evaluation

In general, the major risks associated with the operation of an underground CO2 storage project are related to leakage from the formation.  CO2 leakage from the formation may migrate into potable aquifers or even to the surface, which could result in a significant safety risk.  To evaluate this risk requires an improved understanding of formation properties and how the injected CO2 spreads and interacts with the rock matrix and reservoir fluids.  Geologic formations typically consist of layers of rock with different porosities, thicknesses, and chemical compositions.  All of these factors affect the suitability of the formation as a site for CO2 sequestration.  Porosity and thickness determine the storage capacity of the formation, and chemical composition determines the interaction of CO2 with the minerals in place.  Also, an impervious cap rock is necessary to prevent the sequestered CO2 from migrating to the surface.  Finally, if the formation consists of a series of aquifers, it is necessary to ensure that CO2 stored in a saline formation does not migrate to a potable aquifer.

For geologic sequestration to be a viable technical option for climate change mitigation, the risks associated with this activity must be evaluated, including environmental, health and safety, and economic risks.  By identifying which aspects of geologic sequestration present potential risks, appropriate actions can be taken prior to the commencement of injection activities to obviate the occurrence of problems.

Risk Estimation

Environmental Risks

From an environmental point of view, leakage is the most serious potential problem.  First, leakage to the atmosphere negates the effort expended in sequestering the CO2.  Leakage serves as a CO2 source and increases atmospheric CO2, as well as representing an economic loss.  Another potential problem is accumulation of CO2 in pockets on the surface of the earth.  Furthermore, CO2 could migrate into other strata, with the potential for contaminating fresh water or causing other problems. If the formation into which CO2 is being injected is below the ocean, leakage of CO2 into the marine environment could affect ocean chemistry and have potentially serious consequences for marine life. Additional risks arise from potential damage to nearby hydrocarbon resources caused by the displacement of fluids by the injected CO2, such as saline water production at wells that had been producing oil or gas.  Finally, if a project does not operate within prescribed injection rates and pressures, there is some potential for initiating seismic activity.

Injected CO2 may interact with formation minerals, which may have beneficial or detrimental effects.  At this time, mineral interactions are not as well understood as transport processes. The interactions may be beneficial by permanently sequestering the CO2 or may be harmful by plugging the formation and reducing permeability. There is some evidence that CO2 injected into coal seams causes the coal to swell, which could affect overlying strata.

Health and Safety Risks Information on the responses of animals and vegetation to elevated and potentially hazardous levels of CO2 and low levels of oxygen (O2) can be found in the literature related to physiology, respiratory physiology, comparative physiology, plant physiology, botany, food preservation, and aerospace. Ecosytem impacts resulting from high CO2 concentrations are less well known than impacts on humans.

Human exposure to elevated levels of CO2 can be hazardous in two ways—by a reduction in the oxygen content of the ambient air causing hypoxia or through direct CO2 toxicity.  The National Institute of Occupational Safety and Health (NIOSH) confined-space-hazard classification system defines CO2 as a nontoxic, inert gas that displaces oxygen [2].  In most cases of hazardous CO2 exposure, the gas is presumed to act as a simple asphyxiant.  However, extensive research indicates that exposure to elevated CO2 concentrations (>3 percent) has significant effects before oxygen dilution becomes physiologically significant. As O2 concentration drops below 17 percent, increasingly severe physiological effects occur until below six percent O2, loss of consciousness is rapid, and death takes place within minutes.

Another safety problem results from the potential for accidents from working around the facilities required to capture, condense, transport, and inject the CO2.  If hydrogen sulfide (H2S) is sequestered along with CO2, health risks are significantly increased, as H2S is highly toxic.

Economic Risks Regardless of the formation chosen for carbon storage, it is essential that its use be economically feasible. Large-scale application of CO2 injection for enhanced oil recovery (EOR) is considered a commercially proven process; however, there are still issues that need to be addressed, a key area of concern being the economic risk of implementing geologic sequestration. It is quite expensive to capture and transport anthropogenic CO2. Retrofitting existing pulverized coal (PC) fired units with currently available CO2 post-combustion capture and storage technologies could increase the cost of electricity by as much as 65 percent. In the case of integrated gasification combined cycle (IGCC) plants with pre-combustion capture, cost increases are expected to be in the 20-30 percent range (with an ultimate target of only a 10 percent increase).

Aside from the issue of the effect on power costs, there are other economic risks that need to be considered.  Economic liability could result if, for example, a pipeline were to rupture and cause injury or death.  Such risks are routinely faced by industry and are typically covered by purchasing insurance. Also, a sequestration project might fail to operate as planned.  For example, it might be discovered that the site is unsuitable because of the presence of an undetected fault, thus requiring abandoning the project and forfeiting the investment.

There are also risks associated with potential leakage from a storage site.  If such leakage were to result in a high enough CO2 concentration to cause harm, liability could result.  CO2 leakage could result in other types of economic liability.  If, for example, a carbon tax were instituted, then CO2 leakage might be treated as a CO2 source and the sequestration project operator might have to pay a tax on the CO2 leakage to the atmosphere. Economic liability could also arise if CO2 leaked into a potable aquifer and caused problems, or if injected CO2 caused water to be produced at a hydrocarbon well that had been producing oil or natural gas.

Risk Control

As indicated above, one of the major risks associated with CO2 sequestration is the potential for leakage.  In order to reduce this risk, technologies are needed for the measurement, mitigation, and verification (MMV) of stored CO2.  MMV is concerned with the capability to measure the amount of CO2 stored at a specific sequestration site, map its spatial disposition, develop techniques to mitigate potential leakage, and verify that the CO2 is stored or isolated as intended and will not adversely impact the host ecosystem.  MMV for geologic sequestration consists of three areas: modeling and analysis of the geologic structure before injection occurs, subsurface monitoring of the movement of the CO2 plume, and above-surface measurements that verify that the CO2 remains sequestered [3].

Modeling and Simulation Prior to Injection Prior to initiating a CO2 injection project, the target geologic structure must be thoroughly understood, and the movement of the injected CO2 must be reasonably well predicted in order to properly site above-ground measurement equipment.  A number of models and simulation software packages currently exist to track the movement of underground fluids; however, none are designed for geologically sequestered CO2 plumes.   Modifications to any existing models and simulators to accommodate CO2 were done for EOR analysis.  To effectively model underground CO2 behavior, three basic types of models are available:

• Standard reservoir simulator

• Geomechanical simulator

• Geochemical simulator

Which one or combination of these are used will depend on the geological attributes of the storage site and the major risks. These simulators can be tailored to meet the unique needs of CO2 injection and geologic sequestration. Significant understanding of candidate geologic sequestration sites already exists; however, gaps still remain in understanding how CO2 will behave at these sites.  Application of MMV simulators to CO2 injection will improve the knowledge base and provide greater accuracy of detecting CO2 movement in underground structures.

Subsurface Measurement of CO2 Plume Movement Geophysical tools, such as fluid movement monitoring and seismic studies, will be used to monitor injected CO2 behavior in targeted structures.  These tools will validate and/or calibrate the pre-injection models and simulations and also provide locations of potential above-ground leakage.

Surface Verification That CO2 Remains Sequestered Surface verification that the injected CO2 remains sequestered will take place near or above the surface of the underground formation.  These surface MMV methods involve the direct detection and measurement of the CO2 or, in some cases, of tracer substances moving with the injected CO2.  However, large-scale surface verification detection systems have not been tested to determine if they have sufficient accuracy.

Risk Monitoring

The Mountaineer Project consists of drilling a 9,200 foot well in the Ohio River Valley to determine if the geology of this region is suitable for the injection of CO2 into saline formations.  The site for the project is American Electric Power’s (AEP) Mountaineer plant near New Haven, WV.  Prior to drilling the well, seismic studies were conducted to characterize the area. The Ohio River Valley is believed to be an ideal candidate for carbon capture and sequestration because of the nature of the geology of the area and because the region is home to many fossil fuel-fired electric generation plants.  The data generated by this project are being used for CO2 sequestration simulations, risk assessments, permit applications, and the design of monitoring facilities for future CO2 injection projects.  Based on the site characterization results, several potential CO2 injection zones have been identified.

Risk assessment is an important part of this project.  This includes site characterization, storage and migration modeling, identification of potential hazards and their risk, and final risk assessment.  This information will be evaluated to develop risk management procedures.  The conceptual site framework is being used with the reservoir models to simulate injection scenarios for various injection well designs and injection rates.  Atmospheric and aqueous dispersion models may be used to evaluate the impact of any CO2 buildup in shallow water or air and to design monitoring systems.  The site information and simulation results are put into a risk assessment framework which includes hazard identification/analysis, dose-response assessment, exposure assessment, and consequence assessment.

Discussion

Performance assessments and projects that have been conducted have shown that geologic settings are highly suitable for longterm subsurface storage of CO2.  These studies have highlighted the significant capacity of the geosphere to effectively store CO2 and prevent its migration to the biosphere.  Suitable formations include depleted oil and natural gas formations, unmineable coal seams, and saline formations.

Health effects should be minimal from slow leakage of CO2, since low levels of CO2 are nontoxic.  The major risk to life would appear to be from a massive leak of CO2, such as might occur from a pipeline rupture, a well blowout, or the opening of a fault.  Years of pipeline operations with natural gas and, to a lesser extent, CO2 should provide the experience needed for the safe design, operation, and management of CO2 pipelines.  However, there is always the chance that seismic or construction activity could lead to pipeline rupture.  The Weyburn risk analysis indicated that the most probable path for transmission of CO2 from one stratum to another or to the biosphere is along a well bore. Therefore, wells must be carefully drilled and monitored.  If CO2 sequestration is practiced in depleted oil and natural gas fields, then the presence of abandoned wells could cause problems. These wells will need to be effectively plugged and monitored. If H2S, sulfur oxides (SOx), or nitrogen oxides (NOx) are sequestered along with CO2, then potential health risks from slow leakage are considerably greater.

The largest uncertainty about leakage may come from sequestration in saline formations, since the presence of an impermeable cap rock is not as certain as in the case of depleted oil and natural gas reservoirs.  CO2 in coal seams should be

relatively stable as long as the seam is otherwise undisturbed.  The methane in coal seams has been kept in place for perhaps millions of years, and there is no reason that CO2 cannot be sequestered for at least thousands of years.

In addition to health and environmental risks, there are technical risks.  The major technical risk is that the injected CO2 will affect the strata into which it is being injected in such a way that permeability and/or porosity is decreased, thus limiting the rate or quantity of CO2 that can be injected.  Decreased permeability can be overcome to some extent by increasing injection pressure, but this increases cost, and there is a limit to injection pressure to avoid fracturing the cap rock.  These risks will be decreased by employing the data generated by pilot projects, but the risks will need to be included in project risk assessments.  Ultimately, the risks associated with geologic sequestration identified in this paper, which are believed to by already low will be further mitigated by effective and comprehensive risk management strategies.