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By Peter J. Tarkoy

A great deal of attention has been directed toward the complexities and inadequacies of exploration and pre-bid geotechnical information for heavy construction projects, differing site conditions, and the adversary relationships which generally develop as a result. The adversary position has been maintained at all cost. The solution is simple, if not easy. The solution requires strict and equal adherence to given principles by all parties involved, throughout the life of the project, from conception to completion. It is necessary to review and redefine some basic concepts, without value judgements, from a context of getting the job done. In a recreated context, the role of truth, judgement, responsibility, and integrity, in exploration, engineering design, construction estimating, and project construction, will be examined. It is suggested that anticipated geotechnical conditions be defined unconditionally. The alternative choice is to give the bidder the opportunity of making the interpretive judgements based on geotechnical data. Similarly, a unilateral method of establishing encountered conditions that are agreeable to both owner and contractor, must be outlined prior to contracting. As anticipated and encountered conditions are firmly and accurately established, significant differences can evaluated based upon limitations specified in the contract documents. Impact of differences on project costs can be fixed by pre-defined methods.

Jan 1, 1983

By G. Robson

"From monitoring gas levels and air quality in coal mines to protection from collisions for large vehicles at mine sites, SICK offers a wide range of sensors and systems to improve safety and to monitor potentially dangerous situations. SICK offers solutions for the analysis and monitoring of underground coal mining atmospheres. These systems supply the coal mine operator valuable safety and ventilation information, as well as data which identify and monitors atmospheres of those production areas within the mine which may or may not be worked, such as Goafs and sealed areas. Underground coal mines contain dangerous gases, which must be monitored and controlled in order to allow productive mining operations to take place and to minimize the risk of explosion. Underground mines are a potentially dangerous place for mine workers. These are the main reasons for using Tube bundle systems SICK has had great success in selling these systems into the Australian and New Zealand Markets and this is helped by the strong drive for mine safety from both the Mine Owners and the Regulatory bodies charged with the responsibility of ensuring Mine Regulations are met. The Australian mining industry uses Tube Bundle Systems at almost all underground sites, even after mining has ceases and the mine is placed in care and maintenance. Sick has been working in international markets for some time now but has had limited success in selling Tube bundle Systems to these markets. However in recent times there has been raised interest in Tube Bundle from China, India and Turkey as these countries strive to improve mine productivity and lessen the risk of explosion or Spontaneous Combustion. Our lack of penetration into International Coal markets has been very much based on the perceived cost of the system, not the benefits to safety and productivity. Unless a mine has had an event such as spon com or a Methane explosion they rarely consider the very low level measurement capability (20 PPM CO & 100 PPM CH4) or the long term trending benefits of the Tube Bundle system. It is only after a catastrophic event the System is considered. Real Time or electrochemical Sensors are commonly used to monitor the Mine Atmosphere, the real problems of methane build up or potential Spon Com in Goafs and sealed areas cannot be monitored using Real Time Sensors as the electrochemical cell deteriorates after approx. 12 months and in sealed areas these cells cannot be maintained or replaced. Whilst the Technique of Tube Bundle Systems is quite old SICK have spent many years redesigning the Tube Bundle System into a cost effective and real value for money product. The system uses state of the art sampling and highly accurate Infra-Red wide Spectrum Analysers."

Jan 1, 2016

By Karl R. Zipf

A tube bundle system (TBS) is a mechanical system for continuously drawing gas samples through tubes from multiple monitoring points located in an underground coal mine. The gas samples are drawn via vacuum pump to the surface and are typically analyzed for oxygen, methane, carbon dioxide and carbon monoxide. Results of the gas analyses are displayed and recorded for further analysis. Trends in the composition of the mine atmosphere, such as increasing methane or carbon monoxide concentration, can be detected early, permitting rapid intervention that prevents problems, such as a potentially explosive atmosphere behind seals, fie or spontaneous combustion. TBS is a well-developed technology and has been used in coal mines around the world for more than 50 years. most longwall coal mines in australia deploy a TBS, usually with 30 to 40 monitoring points as part of their atmospheric monitoring. The primary uses of a TBS are detecting spontaneous combustion and maintaining sealed areas inert. The TBS might also provide mine atmosphere gas composition data after a catastrophe occurs in an underground mine, if the sampling tubes are not damaged. TBSs are not an alternative to statutory gas and ventilation airflowmonitoring by electronic sensors or people; rather, they are an option to consider in an overall mine atmosphere monitoring strategy. This paper describes the hardware, software and operation of a TBS and presents one example of typical data from a longwall coal mine.

May 1, 2013

By R. Krog, M. Valente, R. Ochsner, W. Marchewka, R. Jensen, R. K. Zipf

A tube bundle system (TBS) is a mechanical system for continuously drawing gas samples through tubes from multiple monitoring points located in an underground coal mine for analysis and display on the surface. The U.S. National Institute for Occupational Safety and Health (NIOSH), in collaboration with Signal Peak Energy (SPE), LLC, Bull Mountains No. 1 Mine, operated a TBS during mining of two bleederless, longwall panels. This paper describes the gas analysis data and its interpretation. As verified by the TBS, coal at the SPE mine tends to oxidize slowly. It was known that a reservoir of low-oxygen concentration atmosphere developed about 610 m (2,000 ft) behind the longwall face. A bleederless ventilation system facilitates formation of an inert atmosphere in this longwall gob and decreases the likelihood of spontaneous combustion. Connections of the mine atmosphere to the surface through subsidence cracks could allow airflow into the longwall gob, revive coal oxidation and increase spontaneous combustion risk. The atmospheric composition of the sealed areas was homogeneous, except in the immediate vicinity of suspected ingassing points. The TBS verified that gases within the partially sealed, bleederless longwall gob expanded into the longwall tailgate area when barometric pressure decreased. The concentration of carbon dioxide in the back return airflow at the longwall tailgate was observed to increase by a factor of three and possibly up to 10 times the typical background concentration of 0.5 to 1.0%, depending on the size of the longwall gob and the magnitude of barometric pressure decrease. TBS have the inherent disadvantage of slow response time due to travel time of the gas samples and sequential gas analyses. A TBS or similar continuous monitoring system could be beneficial in detecting and providing warning of potentially hazardous gas concentrations, if the slow response time of the system is always understood.

Jan 1, 2013

"HISTORY Tube bundle systems have been used in the coal mining industry for gas detection since the 1960’s. At the time there were developments were underway for improved gas monitoring systems. The primary gas detection systems in use were the flame safety lamp, colorimetric stain tubes and the taking of samples for analysis by gas chromatography. The MSA D6 hand held methanometer was approved in the UK for statutory methane measurements in 1972 and became very popular due to its smallness and simplicity of use. In 1973 Sieger Limited also developed a BM1 methanometer which could be installed underground and relay methane concentrations to the surface. Similar developments were underway for carbon monoxide detection and one was developed in 1982 by the Yorkshire Regional Laboratory of the NCB commercial development was undertaken by Sieger Limited who named it the ‘SCO1’. The UNOR 1 carbon monoxide and methane analyzers were approved for underground use in the United Kingdom in the late 1960’s.5 The technique was developed by Dr Luft of Bergbau-Forschung Essen and the equipment was manufactured by Maihak in Germany. The apparatus was flame proof and provided an intrinsically safe output which allowed the result to be telemetered to the surface through colliery communication systems. Both analyzers work on the same principal and each of the gases adsorb a certain wavelengths of infrared radiation. The detector measures the residual transmitted radiation and determines the percentage of gas present in the sample. These flameproof versions had proven to be robust and reliable. The UNOR 1 had been used in the Saar region of Germany and Scotland in the UK. The development of tube bundles for hydraulic controls enabled the development of the tube bundle gas monitoring systems we know today. A bundle of tubes are taken underground through a shaft, a borehole or drift then distributed to the required monitoring points. This enabled the ongoing monitoring of the underground environment when the power was isolated at 1.25% CH4. In 1972 the United Kingdom (UK) National Coal Board (NCB) produced a hand book for tube bundle systems which was subsequently updated in 1974. This is a useful guideline into the operational aspects of tube bundles systems at coal mines6. Many of the processes identified are being followed today. The United State Bureau of Mines (USBM) prepared a circular similar to the NCB handbook on tube bundle systems.7 The circular was prepared by Litton C and it was targeted at the design criteria for tube bundle the systems. The circular also states that “pneumatic monitoring systems can be used to monitor for hazards that develop quite quickly”."

Jan 1, 2016

By J. D. Decker, T. E. Norman

Introduction Grinding is the reduction of ore and similar raw materials to particle sizes below the practical limits of commercial crushing ma¬chines. This size is about 36 in. (1 cm), in most cases, although some finer crushing machines are in regular use. The feed size to grinding machines may range upward to S in. in rod mills, and 12 in. or more in autogenous mills. The finest particle sizes produced in mineral processing operations result from grinding. Ordinary grinding of brittle materials is the result of impacting, rolling, and abrasion of heavy bodies, moving freely under the influ¬ence of gravity. These falling and rolling grinding bodies, which are usually of metal, must be much heavier and larger than the ore parti¬cles they break. This weight relationship is usually in excess of 100: 1. The sustained fall of the grinding bodies is obtained by placing them, together with the rock particles they grind, in a rotating drum or cylinder with horizontal axis, called a tumbling mill. The mill is nearly half full of grinding bodies and ore particles, which may be fed into one end and exit from the other through hollow trunnions which usually serve as the mill bearings. The mill lining must be thick to absorb wear and rough to prevent excessive slippage of the charge. The breakage of brittle rock or ore is accomplished by compression. The compression may be a rapid impact, from the fall and roll of a grinding ball, or it may result from the relatively slow and constrained motion as in a jaw crusher. Breakage by shear is a secondary result of the compressive motion. Ordinary rock has an extremely heterogenous structure with innumerable zones of weakness in which cracks, fractures, and breakages can form. When a rock is subjected to com¬pression it deforms. If the compressive force exceeds a certain critical value an incipient crack appears in the most fragile zones of weakness. This crack tip may first form on the particle surface or in its interior. When the first crack tip forms the compressive stresses immediately surrounding it flow to it, and this concentration of forces extends the crack and splits the rock. Other adjacent cracks may form during this extremely rapid process. Because of the nature of brittle particles, the work done in breaking them consists essentially of the work input required to compress them to the point at which the first crack tip forms. Breakage requires no appreciable additional energy input be¬yond that required for the deformation, since the stress energy already imported to the rock flows to the crack tip and extends it to breakage. Types of Tumbling Mills The general term tumbling mill includes the rod mill, ball mill, pebble mill, autogenous mill, and tube mill. It is of cylindrical or cylindro-conical shape and rotates about its horizontal axis. Rotational speed, liner type, and size and shape of tumbling media are selected to provide the desired operating conditions for the specific grinding application. Openings are provided through the mill ends for feed and discharge of the material being ground. A common feature of tumbling mills is the use of tumbling media

Jan 1, 1985

By Donald I. Bleiwas

The U.S. Bureau of nines evaluated the potential availability of tungsten from 57 tungsten mines and deposits in 19 market economy countries (1). The 38 properties that were producing at the time this study was performed contain approximately 375,000 tons1 of W03 (tungsten trioxide). The total estimated recoverable resource from all properties studied, both producers and nonproducers, was 1.2 million tons W03 (demonstrated level). Approximately 143,000 tons of W03 is recoverable from producing properties with costs at or below the January 1983 market prices. The study indicates that by 1990 production from currently operating mines in market economy countries will decrease as their demonstrated resources become exhausted. Some of this potential decline may be offset by lower than anticipated levels of market demand, discoveries of additional resources at producing mines, development of other known deposits, and/or discoveries of new deposits. Development of new tungsten resources in market economy countries will likely result in costs higher than exist at currently producing properties. The People's Republic of China has been steadily increasing production and export of tungsten in various form and currently supplies about 25 pct of U.S. imports. China's tungsten mines are large, high-grade operations capable of producing at relatively low cost. These factors, coupled with China's apparent need for foreign exchange, could lead to further expansions of production and exports from China, with a consequent increased dependence by market economy countries on China for tungsten requirements and a threat to the survival of the market economy countries' tungsten industries.

Jan 1, 1984

By I. S. Parrish

This article offers one of the infrequent looks at Chinese mining. It includes a brief review by Parrish of a tungsten symposium held there and his comments on and impressions of the mines he visited. In early Oct. 1981, a Symposium on the Geology of Tungsten was held in the Peoples Republic of China. There were approximately 100 participants. Half of them were Chinese. The remainder included representatives of the United Nations, geologists from other nations in Southeast Asia, and 10 invited specialists from other countries. The invited guests included K.F.G. Hosking of the Camborne School of Mines, United Kingdom; C.S. Hutchinson of the University of Malaysia; K. Mattson of LKAB Int. AB, Sweden; T. Kwak of Latrobe University, Australia; K. Sato and S. Ishihara of the Geological Survey of Japan; M. Clarke of the Department of Mineral Resources, Indonesia; P. Bateman of the US Geological Survey; and the author. R. Horsnail of Amax was also invited but was unable to attend because of delayed visa clearance. The meeting was noteworthy because the Chinese were presenting more than half the papers. In addition, following the formal session, everyone was taken to the famed Jiangxi tungsten district and toured four mines there. Organization and Background The idea for a symposium on tungsten geology was brought up in late 1979 during a visit to China by the Economic and Social Commission for Asia and the Pacific (ESCAP) and, in particular, by members of the Regional Mineral Resources Development Centre (RMRDC) of the United Nations. Discussions continued and in the spring of 1981 invitations were sent to selected geologists throughout the world. China's Ministry of Geology handled arrangements, scheduling, and logistics. Travel to China and all correspondence before the symposium were coordinated by the Bandung, Indonesia Bureau of RMRDC. All costs in China were met by the Peoples Republic of China. Airfares and "per diem" enroute for participants were paid by respective governments, sponsors, or individuals. On Oct. 10, visiting participants entered China from Hong Kong. The author and a few others traveled by train to Guangzhou (Canton). Most of the group flew in the next day. The entire group was then taken to Nanchang, traveling by sleeper train and arriving on Oct. 11. The symposium group stayed at the Kiangsi Hotel, where the meetings were held. Meetings Oct. 11 was a day of orientation and rest. The group was taken to an art museum and treated to a Chinese opera movie. The formal meetings began on Monday, Oct. 12. Simultaneous translations aided presentations, though more than half the Chinese speakers delivered their talks in English. The acoustics and sound system were excellent, and the Chinese provided 35-mm and overhead projectors. There was no screen, however, and the yellow, painted wall that was used detracted from projection clarity. In general, the Chinese papers were detailed, thoughtful, and professional. Some, naturally, were stronger than others. Taking them as a unit, one derives the following sequence to the Chinese approach to tungsten exploration: (1) Geologic investigations with mapping at a scale of 1:200,000 accompanied by only minor geochemical or geophysical work. (2) Geophysical investigation with regional gravity and magnetic surveys directed toward identifying deep, tectonic systems and seeking granites in thick, crustal environments. (3) Geochemical sampling in-

Jan 6, 1982

By Y. Guo, C. Cao

"China is rich in tungsten resource, but they are mainly associated minerals. The similar flotability of scheelite, fluorite, and calcite resulted in the difficult separation by flotation. This work summarized the current situation and the development of flotation reagents, technological process, and mineral processing equipments in China. Fatty acid served as the collector and water glass was the depressant to expand the flotability differences in traditional flotation technology. However the water glass inevitably influenced the flotation of tungsten minerals to a large extend, and the suppressed fluorite was difficult to recover by flotation. Abundant water glass lead to the bad settleability of the tailings and the tail water was difficult to circulate, resulted in serious environmental problems. Recent study proved that the selectivity of benzene armour hydroxyl oxime acid (BAHA) salts was adequate for the separation of tungsten minerals from fluorite, calcite and most silicate minerals without any depressant. By this way, sodium silicate was canceled completely in tungsten flotation, greatly improving the recovery of tungsten and the environmental problems caused by tail water treatment would be solved fundamentally. TUNGSTEN RESOURCES AND DISTRIBUTION IN CHINA China is rich in tungsten resources and the proved reserves accounted for 60% of the world's reserves [1]. However the wolframite has been dried up and the scheelite resources had become the main resource of the tungsten metal. Table 1 showed the most large and superlarge scheelite deposits in China. China has more than 40 large and superlarge scheelite deposits and the total metallic deserves is more than 3 million ton [2]. But most of the deposits were low-grade and the associated relationship was complicated. For example, scheelite was usually associated with wolframite, molybonite, bismuthinite, pyrite, fluorite, and calcite in Shizhuyuan and Yaogangxian mine."

Jan 1, 2016

By P. B. Altringer

The Bureau of Mines conducted laboratory tests to develop a process for recovering a marketable grade of tungsten from the brine of Searles Lake, Calif. The brine contains only 56 parts per million of tungsten (70 ppm WO3). Using ion exchange resins synthesized by Bureau chemists, 98 percent of the tungsten was extracted from the brine and 92 percent of the tungsten vas recovered as a marketable iron-tungsten concentrate containing 44 percent tungsten as tungsten trioxide. Although major technical problems have largely been resolved, research is progressing to escalate testing in a process investigation unit to provide more reliable data for an economic appraisal.

Jan 1, 1978

By Gordon T. Clark, Stephen H. Gleaton

This paper discusses the conceptual design of cut-and-cover tunnels currently being considered as one of the replacement options for the earthquake damaged, elevated double-deck highway and seawall built in downtown Seattle 50 years ago. The 4.8 km (3 mile) long, 6-lane improvement consists of 1.6 km (1 mile) of at-grade roadway with aerial interchanges, 1.6 km (1 mile) of large two-level cut-and-cover tunnels along the Elliott Bay waterfront, and retrofit of the 50-year old, 1.6 km (1 mile)long Battery Street tunnel and north transition to grade. Construction of deep cut-and-cover tunnels, in complex glacial geology overlain by hydraulically placed fill immediately adjacent the existing sea wall, will require extensive use of concrete diaphragm walls, ground improvement and dewatering. The potential liquefaction and lateral spreading of the fill materials in this active seismic region pose significant design challenges and risk.

Jan 1, 2003

By L. A. Garfield

Since the start of mining operations at White Pine in 1953, over 22 miles of drifts have been driven for the purpose of developing the ore body. The drifts, normally driven in multiples of three or five headings, serve as conveyor belt routes, ventilation ducts, equipment and haulage roads, and initial access to mining blocks. Development openings in the flat-lying, bedded ore body are driven in rectangular section from 16 to 32 feet wide and from 8. 5 to 16 feet high. The floor level normally coincides with the bottom limit of the chalcocite values and the roof or back is carried at the most competent stratum adjacent to the top of the ore. A development front consisting of five headings and associated crosscuts is advanced at an average rate of about 100 feet per month using conventional drill and blast techniques and equipment. The cyclic nature of the functions involved in driving the openings and the need to include them in production schedules preclude significant improvements in advance rates using current drill, blast, muck, and haul sequencing.

Jan 1, 1969

By J. J. Scott, G. H. Bennett

INTRODUCTION Friction Rock Stabilizers, commonly called Split Sets,tm* have been under development since early 1973. Five years of intensive laboratory and field testing led to their introduction to the metal mines in the United States in the fall of 1976. Actual sales started in February of 1977 and, to date, over five million units have been marketed to metal mines. The present rate of useage is near 3 1/2 million units per year which is approximately 50 per cent of all roof fixtures used in the United States metal mining industry. Mr. Richard Hoppe, Senior Editor of Engineering & Mining Journal, in an article of the February, 1979, issue, entitled "Winning the Battle Against Bad Ground", said, "In hardrock mining operations in the western U.S., particularly underground uranium mines where exceedingly difficult ground is common, no roof support system has been accepted more quickly than the Split Set friction bolt invented by Dr. James J. Scott and developed by Ingersoll-Rand Co." This paper describes how Friction Rock Stabilizers function and presents technical data to show the uniqueness of the Friction Stabilizer system. SPLIT SET STABILIZERS The Split Set System is a revolutionary development in the field of ground control. The system produces an interior reinforcement to a rock mass which: *Trade Mark of Ingersoll-Rand Co.

Jan 1, 1979

By Marco Sonnenschein

Belt conveyors for tunnelling are industry standard and key to high performance of TBM drives. Conveyors reduce traffic in the tunnel and increase safety in the tunnelling process. This paper will illustrate the state of the art of tunnel belt applications in very long and curvy tunnels like the Coxwell Bypass Tunnel Project in Toronto, Canada.

Jun 23, 2024

By Clayr Alexander

Stillwater Mining Co. (SMC) is engaged in developing, extracting, processing and refining palladium, platinum and associated metals (PGM)from the J-M Reef. This geological formation is located in Stillwater, Sweet Grass and Park counties in southern Montana. Associated byproduct metals include rhodium, gold, silver, nickel and copper. SMC’s current mining operations are near Nye, MT. The company is currently developing a second underground palladium and platinum mine, the East Boulder project, about 21 km (13 miles) west of the Nye operations. A 5,650-m (18,550-ft) tunnel is required to gain access to the ore-bearing horizon (J-M Reef).

Jan 1, 1999

By Cherie M. Tilley

The Stillwater Mining Company has acquired a Tunnel Boring Machine to expedite the mine development operations at its Stillwater Mine. The machine purchased by Stillwater was previously owned by Melbourne Metropolitan Board of Works, Melbourne, Australia. The machine was manufactured by Robbins Co. of Kent, Washington. The Stillwater Mine has an extensive system of footwall laterals which are required by the mine development scheme. The initial mine plan called for in excess of 30,500 linear meters (100,000 linear feet) of footwall lateral drifts at a cross section of approximately 3.0 meters in width by 3.75 meters in height (10 feet x 12 feet). A Tunnel Boring Machine was selected for this work. The Robbins machine number is 146-193. This machine is approximately 4 meters (13 feet 5 inches) in diameter. The machine was modified extensively prior to commencing operation at the Stillwater Mine.

Jan 1, 1989

By M. Grun, A. C. Marlowe, I. Littleford

SYNOPSIS A Wirth tunnel borer owned by Anglo American Corporation completed a 1150m long tunnel some years ago and was subsequently extensively modified by Technical Development Services. In 1982 this borer provided new and particularly interesting information In the field of hard rock boring. The abrasive quartzltes traversed proved to be a challenge to the cutter manufacturer and the project team. This paper examines the problems faced, the solutions found and the lessons learnt.

Jan 1, 1983

By Rock M. Poulin, Bruce G. Moulton, Daniel E. Nowak, David T. Cass

The Yacambu Irrigation Tunnel Project of 34 km, 5 meter diameter circular and horseshoe section, has been under construction since the early 1970's. Notable among the excavation challenges is high ground cover of 3,000m creating large lithostatic pressures in the tunnel alignment with subsequent plastic flow of the ground in the tunnel walls. The tunnel may converge from small amounts to 1 or more meters of diameter over long sections. Several excavation techniques have been attempted but all without desired results. The paper proposes a new machine concept that uses the history of ground experience as its basis for design.

Jan 1, 1995

By Martin Herrenknecht

Tunnel boring machine (TBM) development continues to take on not only larger diameters, but also more difficult ground conditions. Ground conditions consisting of unstable faces with water pressures up to 15 bar have required innovative design approaches. A systems approach has been required to produce tunneling machines that can safely excavate the tunnel in an efficient, cost-effective manner that stresses production and labor saving approaches. This article reviews the current design developments and present recent projects where these most recent principles have been applied. The world?s growing population and rapidly proceeding urbanization are boosting an enormous demand for new and high-capacity infrastructures to secure the mobility of goods and people. Densely populated areas face the challenge of providing efficient traffic infrastructure such as a modern public transport system. At the same time, the maintenance and modernization of supply and disposal structures for water, sewage, energy and communication are essential. Last but not least, are supra-regional transportation routes such as long distance water diversion schemes. All of these projects are as demanding and are characterized by a tight time schedule. In this context, the demand for efficient tunnels for traffic and utility lines is increasing, as new infrastructures often leads underground because of limited space above ground. Also, tunnels are the obvious choice to cross natural barriers like mountain ranges. To handle the complex and variable geological conditions and other constraints, such as low overburden, high water pressure or long tunnel drives while facing increasing demand of a quick completion of a project, mechanized tunneling sets standards regarding safety, profitability and environmental protection in traffic tunneling projects as well as in the trenchless construction of utility tunnels. Different machine types and working principles have been developed to master various geological and hydrogeological requirements. Continuous activity in research and development leads to constant improvement of the mechanized tunneling process.

Jan 1, 2008

By Martin Herrenknecht

Tunnel boring machines continue to develop to take on not only larger and larger diameters but also more difficult ground conditions. Ground conditions consisting of unstable faces with water pressures up to 15 bar has required innovative design approaches. A systems approach has been required to produce tunnelling machines that can not only safely excavate the tunnel but do so in an efficient, cost effective manner that stresses production and labor saving approaches. This paper will review the current design developments and present recent projects where these most recent principles have been applied.

Jan 1, 2008