GB2280835A

GB2280835A - Decontamination of soil

Info

Publication number: GB2280835A
Application number: GB9400331A
Authority: GB
Inventors: Julian David Parry
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-01-09
Filing date: 1994-01-10
Publication date: 1995-02-15
Anticipated expiration: 2014-01-10
Also published as: GB2280835B; GB9400331D0

Abstract

The soil treatment uses physical and/or chemical and/or microbiological processes and utilises a number of lances 20 used to suppy fluid (eg compressed air) to a treatment block 21 to treat contaminant therein. As shown, the lances 20 are connected to a unit 22 connected to sources of fluid supply 23, 27, a nutrient source 25 being provided to promote activity of microorganisms. Various lance constructions and arrangements are described (see eg Figures 1B - 3B) involving computer controlled valves, and operation of unit 22 is described in detail. <IMAGE>

Description

SOIL TREATMENT The present invention relates to the treatment of soil. It is particularly, but not exclusively concerned with the bio-remediation of soil, in which micro-organisms are used to degrade contaminants in soil. However the present application is applicable to soil treatment using physical and/or chemical and/or microbiological processes.

The treatment of contaminated soil is an important problem, for health reasons and because contaminants may pass from the soil into the water supply. However it has proved difficult to effectively remove contaminants from many soils, especially where those soils are dense and in particular from cohesive soils such as clay.

There are number of known ways of removing contaminants from some soils, each of which is called a migratory pathway and these include:direct suction, (direct pumping of free flowing fluid contaminants and contaminated groundwater) leaching (infusing another innocuous fluid to displace the contaminant and make it available for extraction by direct pumping).

solubilisation (dissolving of the contaminant in groundwater or another fluid infused for the purpose of separating the contaminant from the soil and making it available for direct pumping.

volatilisation (removing volatile fractions of a contaminant by drawing air through the scil) bio-remediation (removing contaminants by micro-biological means in which soil resident microbial populations of fungi, bacteria and yeasts are encouraged devour or 'metabolise' the contaminants to obtain energy for their own life functions. In so doing the contaminants are changed to new chemical forms which are generally innocuous.

Where bio-remediation is carried out in the absence of oxygen the process is said to be anaerobic. Where the bio-remediation is carried out in the presence of air or oxygen the process is said to be aerobic. Aerobic bio-remediation changes contaminants by a process of oxidation which will usually provide a safe environmental fate for the contaminant provided always that it is suceptible to this form of remediation. In the case of hydrocarbon contamination the environmental fate is to produce carbon dioxide and water.

Where the bio-remediation cannot be achieved utilising indigenous soil resident microbial populations it may be reinforced by the introduction of other microbial populations selectively grown and obtained for the purpose of augmenting the indigenous population.

Such a process is already known and is termed "microbial augmentation".

The larger and more active the microbial population becomes, the more swiftly is the contaminant metabolised and removed. Moreover the reproductive cycle of many micro organisms can range from a few minutes to many hours depending not only upon the ambient conditions of food supply, but also upon the ambient temperature, and pH level. It has been long established that most microbial populations thrive between temperatures of about 15-40 degrees centigrade and further research has shown that many soil borne bacteria thrive best at a pH of about 7.2 The purpose of bio-remediation is exploit all of these features. In this manner the desired microbial population is expanded and stimulated to increase its metabolic rate.

Such stimulation is achieved by creating subterranean conditions conducive to the increased microbial activity (including reproduction) of that co-operative sector of the soil resident population which is capable of metabolising the contaminant. Those subterranean conditions are accomplished by infusing a cocktail of those essential nutrients (often including oxygen but excluding those obtained from the contaminant itself), which are required by the soil resident microbial populations to balance its diet Faced with a new food supply (the contaminant) a microbial population will in time and by natural selection expand that proportion of its population which is disposed to use the contaminant as a source of food or energy.However the increased food supply, provided by such contaminants, will not usually contain all of the nutrients required for microbial activity and a supplement is required. Without such added nutrients to balance the diet the vigour and expansion of the microbial population would be curtailed by limits upon the naturally occurring supply of those other nutrients. Increased soil temperatures by infusing hot air and adjusting the pH balance of the soil by infusing water borne chemical such as hydrated lime in suspension are also actions which can be taken as well as infusing new microbial populations selected to accomplish a specific task for which the indigenous microbial population has an ineffective capacity.

It is evident from the forgoing discussion that many different treatment methods are available. However all of them may be considered as the supply of a fluid be it oxygen in air, oxygen in an aerated or oxygenated fluid, nutrients in a carrier fluid, chemicals in a carrier fluid, surfactants in a carrier fluid, or micro-organisms in a carrier fluid. and the word "fluid" will be used in this present specification to cover all such contaminant treating substances.

Additionally the expression "migratory pathway" will be used in this present specification to cover each and any such means of contaminant removal previously described.

The expression "microbial augmentation" or "augmentation" will be used in this present specification to cover the introduction of each and any non indigenous microbial population to the soil by means of the present invention.

There are a range of contaminants which are susceptible to removal from the soil by microbiological processes. These include, but are not limited to, a wide range of hydrocarbon products emanating from the petro-chemical industry. Where the volume of a contaminant is large or where the concentration of contaminants in the soil exceeds a certain level a proportion of it may be removed by one of the physical migratory pathways including, direct pumping, leaching, solubilisation or even volatilisation. However such physical methods cannot always reduce the contaminant to an acceptable level particularly where the contaminant is sorbed to the soil. In such cases one or other form of bio-remediation must be employed if the soil is to be remediated in situ. Most usually, but not exclusively, this is an aerobic bio-remediation.Where the indigenous microbial population is incapable of the degradation then microbial augmentation must be introduced.

The present invention is concerned with the application of all of these methods of contaminant removal in a coherent and co-ordinated manner ensuring that the contaminants within the volumes of affected soil are exposed to these migratory pathways and by such exposure, their removal is obtain.

It is not satisfactory simply to supply an appropriate fluid to the surface of contaminated soil since it cannot then be insured that the fluid will reach the contaminant and thereby be made available to one or other migratory pathways. Therefore, it is known to provide one or more wells in the contaminated soil supply the fluid thereto. This arrangement enable the fluid to reach a variety of levels in the soil along the entire length of the well. It is also known to use a soil penetrating lance being a rigid tube with an open end, with an appropriate fluid being fed through the lance to the outlet and hence to the soil. The word "lance" will be used in this present specification to cover all such soil penetrating lances.

Whilst the effects of various fluids on the contaminants has been considered in detail, the arrangement by which the fluid is applied to a predetermined volume of soil have not been the subject of analysis and treatment methods have been conducted upon a trial and error basis, largely based upon hydrogeological fortune including the existance of an accessible water table.

The present invention, in its various aspects, arises from a desire to provide a more systematic treatment Also to provide a systematic treatment which is capable of utilising all migratory pathways including all forms of bio-remediation including microbial augmentation The principle feature of the SBS Close Lance system is that it is essentially a delivery system capable of utilising all of the known preferential pathways by delivering the necessary resources to all volumes of soil, within a given a site, in virtually any combination or sequence and to be able to change its programme and therefore mode or emphasis of application as the conditions of the site change in concert with progress of the treatment.

The second feature of the system is the manner in which it utilises compressed air, using it to increase the porosity of the subject soil; provide a motive force for the distribution of fluids; facilitate the newly found phenomena of 'soils massage'. by which pollutants may be squeezed from the soil and be the principle source of oxygen which is an essential ingredient of aerobic bio-remediation.

A third feature is that SBS recognises that microbial populations take time to metabolise the food provided and utilises this factor to enable a relatively large volume of soil to be treated individually by relatively small and mobile sources of essential resources upon a repetetive basis.

A fourth feature of the SBS Close Lance System is that it extends the possibility of bioremediation to soils of considerable density. It also provides a means of treating pollution where it lies (even be it beneath existing buildings and other structures) without risking expansion of the plume of pollution by the effects of its own intervention.

By these means the SBS Close Lance system extends the flexibility of in situ soils remediation and furthers the application of bio remediation te soils where, hitherto, such treatment has not be possible.

The Inventor of the present application has appreciated that such systematic treatment can be achieved by conveying the necessary fluids from a variety of external sources to the contaminants within the soil by means of a piped network connected at one end to the sources of the fluids and a waste container or drain, which resources are then selected measured and distributed through the network to soil penetrating lances at the other end of the network by an intervening system of valves controlled by programmable computer manipulating a system of electrical solenoids, pneumatic pistons, electrical sensors, serving pipes and and chambers or reservoirs, all contained within a casing.

When a fluid passes through the outlet of the lance (this including the sucking of air, or groundwater or contaminant or any treatment fluid) into the lance an effective treatment volume is defined around the outlet region of the lance. That effective treatment volume will have definable limits in each physical dimension, which limits may be predicted from some form of test.

That effective treatment volume will depend upon volume of fluid supplied, the viscosity the fluid supplied, the pressure at which the fluid is supplied, counter-balanced by the type of soil, in particular but not exclusively, the compressive strength of the soil and the tensile strength of the soil which are themselves defined by the density of the soil, the mineralogy of the soil, the grain size of the soil, and from thence, the hydraulic gradient of the soil, the permeability of the soil, and the porosity of the soil, all of which can be determined in known ways.

Thus a first aspect of the present invention proposes that a plurality of lances be inserted into the soil with spacing between pairs of lances such that the horizontal dimensions of the effective treatment volumes overlap.

As was previously mentioned, each lance has a tube and an outlet region at an end thereof.

However the vertical extent of the outlet region defines the vertical extent of the effective treatment volume. It has been realised that it is, in some cases, desirable to apply different treatments comprised of different fluids, to different volumes and in particular to apply such different treatments at different depths as respects the surface of the soil.

Therefore a second aspect of the present invention proposes that a plurality of lances are provided and the outlet regions thereof are at different depths as respects the surface of the soil.

In a further development of this idea, treatment at different depths at the same surface position may be achieved either by providing a plurality of lances at that surface position or by providing a modified lance having a number of outlet regions at different positions spaced out along its length with each such region able to pass a fluid independently of any other outlet region upon the same lance.

A third aspect of the present invention proposes that such a plurality of lances in accordance with the first aspect of this invention are arranged in an array, which array extends in at least the horizontal direction such that the horizontal dimensions of the effective treatment volumes overlap. The array may also extend in the vertical direction if a proportion of the lances forming the array extend to different depths as respects another proportion of the lances within the array in accordance with the second aspect of the present invention. Hence it becomes possible to determine an area, defined in the horizontal plane at the surface of the soil, by the aggregate of the horizontal limits of the effective treatment volumes created by the array.Moreover it becomes possible to determine a volume below that area at the surface of the soil, defined in the vertical plane, by the total depth of the effective treatment volumes created by the array. Then the area so defined by the array at the surface of the soil together with the depth of the volumes of effective treatment of soil also defined by the array beneath that surface area can be considered as a three dimensional self contained volume for the purposes of treatment. Such self contained cumulative volumes of effective treatment created by an array of lances are conveniently termed "treatment blocks" and the expression "treatment blocks" will be used in this present specification to cover each and any such self contained volume created by an array.

Where the lances are arranged in an array extending in the horizontal direction, it becomes possible to provide different treatments to the effective treatment volumes, or treatment block, defined by that array. Therefore a fourth aspect of the present invention proposes that it is possible to create regions of different pressures within the treatment block defined by the lances in that array. The regions of different pressures may have the advantage of causing other fluids within the soil such as nutrients, ground water, contaminants, surfactants, or chemicals to move in predetermined directions and in some cases to predetermined extents.

In accordance with the first aspect, the present invention makes use of a plurality of lances.

Those lances then permit a flow of fluid in either direction that is to say either from the lance through the outlet to the soil or from the soil through the outlet into the lance, the actual direction being dependant upon the direction of the motive forces being exerted through the lance at any particular point in time.

As previously mentioned known lances were in the from of ridged tubes with an open end.

It has been found that such an arrangement is undesirable because fluid forced out of the end of the lance tends to push the lance upwards and displace it or even eject it from the ground. Therefore according to a fifth aspect of the present invention it is proposed that each lance shall have at least one outlet region, the outlet region having at least one outlet, which is directed radially of the lance tube. Thus when fluid flows from the lance, the direction of flow is generally horizontal so that there are no horizontal forces tending to move the lance out of the soil.

A lance outlet region may optionally be provided with a series of such outlets directed radially from the lance tube and displaced from each other by a sufficient number of degrees of a circle to accomplish an equal spacing of such outlets around the circumference of the tube and within the overall length of the outlet region along the lance tube. Thus when fluid flows from the lance, the direction of flow is generally horizontal and optionally addressing the surrounding soil through 3600 about the central axis of the lance tube.

Where a single outlet is provided it is normally at the end of the lance. However it is possible to provide a plurality of outlet regions along the length of the lance to provide a multi-stage lance. In each case, the outlet region extends to a predetermined length along the lance.

It is known that lances can be installed into the soil utilising compressed gas directed out of a single orifice at the end positioned within the soil. Where it is desired that lances be provided both with outlets directed radially for operational use and open at the end for installation a sixth aspect of the present invention proposes that the open end outlet surrounding the axis of the lance tube be formed such as to have a slightly smaller internal diameter than the rest of the tube. Once the lance is installed to its appropriate position and depth this open end outlet is blocked by inserting a ball bearing or other suitable spherical synthetic spherical object of appropriate size pressed home with the air of compressed gas leaving only the radially directed outlets available for operational use.

Once the lances are installed and the sources of the fluids are made available the piped network requires a means of selectively causing the required fluid to flow within the system in the appropriate direction, to flow through the appropriate lance or group of lances within the array, and to flow in the required quantity and or for the required time period at the appropriate pressure.

Therefore the piped network may be connected by means of individual hoses, from each lance outlet region to a self contained control unit and thence to the drain, waste container or source of the treatment fluids.

The seventh aspect of the present invention therefore proposes a control unit within the piped network hereinafter termed a Soils Bio-Stimulator and abbreviated to an SBS unit for convenience. The expression "SBS Unit" will be used in this present specification to cover each and any reference to the control unit within the piped network..

The SBS Unit shall have means of connecting to a suitable external electrical supply. There shall also be means of transforming that electrical supply to a lower voltage within the SBS unit casing for reasons of safety. The SBS Unit shall also have a means of providing electrical power to the external suction source under the control of the on-board computer or programmable logical controller.

The eighth aspect of the present invention therefore proposes that the SBS unit contains an internal piped network controlled by a number of valves controlled by an on board computer or programmable logical controller The SBS unit shall also have hose connectable outlets (hereinafter termed a lance-ports) from that internal piped network, dedicated to and compatible with each of the outlet region provided within an array of lances.

Additionally the SBS Unit shall also have hose connectable outlets (hereinafter termed a supply-ports) from that internal piped network, dedicated to and compatible with each of the sources of fluid supply and the drain connection to an external suction pump and thence to a fixed drain or waste container.

It is an essential feature of economic use of the system that fluids shall be supplied to lances in quantities measured by time or volume. The ninth aspect of the present invention proposes that the internal piped network within the SBS Unit shall be provided with and connected to a reservoir of known capacity, mounted internally to the SBS unit casing and controlled by valves upon the internal piped network such that when fluid is to be supplied to a lance it is possible to for the fluid to be drawn into the reservoir by the suction source until it is full, and be expelled therefrom to the lance by supply of high pressure gas to the reservoir from the pressure source.Equally when the reservoir is empty, the high pressure gas may be supplied there through to the lance or the high pressure gas may be diverted to the lance by an alternative route through the internal piped network of the SBS Unit so avoiding the reservoir. This arrangement, using a reservoir of known size which is filled or emptied by the application of one or more of the sources of supply used for other purposes permits the supply of fluid in measured quantities to a plurality of lances to be arranged in a compact manner avoiding the need for separate pumps for each fluid.

The tenth aspect of the present invention further proposes that the internal piped network within the SBS Unit may also be provided at least two additional outlets permitting the connection of an external reservoir of known capacity to the internal reservoir such that any fluid drawn into or expelled from the external reservoir shall be so inducted or expelled at the same time and in similar manner to the fluid in the internal reservoir.

It is often desirable to supply the same fluid to a plurality of lances, for example when the effective treatment volumes about those lances define the boundary of a pressure region within treatment block in accordance with the fourth aspect of the present invention. This can be achieved by the computer simultaneously supplying a fluid to a specified group of lances within the array. The eleventh aspect of the present invention therefore proposes the grouping of a plurality of lance outlets (being a sub-group of the whole array) and their relevant lance ports to a dedicated section of the internal piped network to which supply of a particular fluid may be diverted from the sources independently of any other similar grouping of the lances.

In a development of this arrangement the internal piped network within the SBS unit may consist of separate distribution pipes (one for fluids and one for suction) linked between with mutual branches having one branch for each sub-group of lance ports.

Supply of the appropriate fluid to the appropriate sub-group may be achieved by opening all the lance ports upon the network relevant to that particular sub-group of lances, whilst simultaneously supplying the relevant fluid to that section or branch of the the pipe network serving that sub-group of lance ports. This is acheived independently of any other such sub-group of lance ports by opening the valve isolating the branch from the relevant main distribution pipe containing the fluid or suction desired.

Alternatively the internal piped network may assume a different form wherein a plurality of lances may be connected to a valving arrangement having a plenum chamber, corresponding to a grouping of a plurality of lances within the array, having an inlet and an outlet for the fluids and also a plurality of outlets to the lances. The twelfth aspect of the present invention therefore proposes that the those outlets to the lances are arranged so that there is a moveable plate having a plurality of sealing members thereon, which sealing members are arranged so that there is a position of the plate in which the sealing members may sit against each outlet to a lances or may be lifted therefrom to permit fluid to pass through the plenum chamber to the outlets to the lances.In a development of this aspect the sealing members and outlets to the lances are arranged such that there is a given position of the valve plate at which one outlet to a corresponding lance is open, and the others are sealed.

This may be achieved for example by arranging the outlets to the lances in a circle and having a rotatable disc carrying the sealing members, with those sealing members being arranged equally spaced in a ring with a gap therein, so that the rotation of the disc carrying the sealing members can align with one of the outlets. There would also then need to be a "dummy" outlet which would be sealed by one of the sealing members. When the gap in the sealing members was aligned with the dummy outlet all the outlets to the lances would be closed. With this arrangement axial displacement of the plate away from the plane of the outlets to the lances would open all the outlets to the lances.

The expression "discvalve" will be used in this present specification to cover each and any such means of diverting fluids sealed by means of such a valve with a rotatable and displaceable plate INTENTIONALLY BLANK Embodiments of the present invention will now be described in detail, by way of example, with reference to the drawings in which are listed in the following Table 1

Fig No. Description or title 1A Shows a schematic vertical sectional view of an embodiment of the soils treatment system 1B Shows a plan view of a treatment block illustrating the arrangement of the lances 1C Shows a schematic plan view of an embodiment of the soils treatment system detailing various lance port and supply port connections.

2A Shows a lance for use with the arrangement of Fig 1 2B Shows a sealing arrangement for lance of Fig 2A 3A Shows an alternative lances for use with arrangement of Fig 1 3B Shows a sealing arrangement for the lance of Fig 3A 4 Shows the general arrangement of the fluid supply ports and their connections and controlling valve mechanisms within the basic internal piped network within any SBS unit.

5A. Shows external views of an SBS unit for use in the system of Fig 1 using a valved network in accordance with the eleventh aspect of this invention 5B. Shows the general internal arrangement of an SBS Unit of Fig 4A 5C Shows the nuid distribution network of a soils bio-stimulator of unit of Fig 5A continuing from the network of Fig 4 SD Shows a valve and operating pneumatics for use in the distribution stack of a soils bio stimulator of unit of Fig 5A continuing from the network of Fig 4 6A Shows external views of an SBS unit for use in the system of Fig 1 using a valved network in accordance with the twelfth aspect of this invention 6B Shows the schematic internal arrangement of an SBS Unit of Fig SA 6C Shows the plan view a block containing a discvalve for use in the soils bio-stimulator of unit of Fig 6A continuing from the network of Fig 4 6D Shows a vertical section view a block containing a discvalve for use in the soils bio stimulator of unit of Fig 6A continuing from the network of Fig 4 7 Shows a vertical section view illustrating one arrangement of the lances of the system of fig 1 upon a polluted field.

8 Shows a cross section of a treatment block with lances of fig 3A deployed.

9 Shows and isometric view of a complete system utilising an SBS Unit of fig 6A 10 Shows a detail of a lance influence test rig Shows a plan sectional view of an embodiment of part of the system within a standard container 12 Shows a vertical sectional view of the groundwater recycling and nutrient preparation system all within a standard container 13 Shows the design of the external measuring vessel 24 An embodiment of a soil treatment system according to the present invention will now be described in detail.

Fig 1 shows schematically a vertical section view of the embodiment of the soil treatment system, when mounted in and above polluted ground. In fig 1 the ground has an upper layer or rhizosphere 10, in which living organisms, roots etc. will be present, below which there is a first layer of clay li which itself is above a second, impervious layer of clay 12.

Contaminant, which has been absorbed by the ground at a region 13 forms a plume 14 extending through the rhizosphere 10 and the first permeable clay layer 11, and to the impervious clay layer 12. The soil treatment system seeks to treat the contaminated region corresponding to that plume 14.

As shown in Fig.1 a plurality of lances 20 are inserted into the ground, to define an array of lances within a predetermined region 21 which region is known as a treatment block. As will be described in more detail later the lances 20 are used to supply suitable fluids to the treatment block 21 to treat the contaminant therein. The lances 20 may then be removed and used to define a further treatment block 21, so that all of the contaminated region 14 may be treated. Alternatively a plurality of treatment blocks may be defined by a plurality of arrays of lances 20 sufficient to cover an area of the contaminated region with a plurality of treatment blocks 21 in which the lances 20 are left in situ for subsequent treatments of those individual treatment blocks which they define.

Then lances 20 are connected to a Soils -Bio Simulator (hereinafter and SBS Unit 22) which in turn is connected to sources of fluid supply including an air compressor 23, a suction pump 27, a nutrient source 25, a drain or waste container 26, and optionally an external measuring vessel connected to the internal pipe network of the SBS unit 60.

As will be described in more detail later, nutrient which promotes the activity of microorganisms in the ground which eliminate the contaminant may be pumped from the nutrient source 25 by the suction action of the suction pump 27, so that nutrient passes from the nutrient source 25 to the SBS Unit 22. From the SBS Unit 22 the nutrient may then be expelled under the influence of the compressor 23 and one ore more of the lances 20,. In a similar way, material can be withdrawn from the ground via the lances 20, to pass via the SBS Unit to the waste container 26. Additionally air alone can be allowed to pass from the compressor 23 to the lances 20 without passing through any vessel other than the piped network.

The compressor used in this embodiment may have for example a capacity of approximately 0.2 cubic metres per second at a pressure of approximately 1 mPa. It may also be noted that the SBS Unit 22 may contain an appropriate computer system for controlling the compressor 23 and the pump 27 and the internal valving arrangement within the SBS Unit 22.

As shown in Fig 1, the lances 20 extend to different depths in the ground, and each lance has one or more outlets for the passage there through of fluid to or from the SBS Unit 22.

A lance 20 with a single such outlet region is hereinafter referred to as a single stage lance and a lance with a plurality of such outlet regions is herein referred to as a multiple-stage lance. The stages in any individual treatment block may be numbered in sequence from the surface of the soil such that the upper most stage is satge 1, the stage immediately below stage 1 is stage 2 and so on in sequence to the lowest most stage in any given sytem and this method on numbering shall be used hereinafter in this application.

It is important in any embodiment of the soils treatment system that lances shall be identified as to their position and carefully connected to the appropriate port on the SBS Unit 22 Fig 1A details the sequence of such connections where a lance in the array with denoted by an upper case letter must connect to a lance port denoted by the same letter in lower case script.

Where a two stage lance system is used the sixteen ports required to service the sixteen lance stages of stage one would be directly adjacent to the ports serving stage two on each SBS Unit 22 and each lance in the stage 2 frames would be denoted by the same letter as for the stage one frames and would be similarly connected exclusively to the stage two outlet region to permit proper co-ordination of the supply and direction of flow of the fluids used in the treatment of the contaminated land 14.

The SBS Unit 22 is provided with outlets serving the internal piped network cf the SBS Unit 22 such that the sources of supply of fluids for the treatments can be supplied from the compressor 23, or suction from the the pump 27, or the nutrient supply 25, or the external measuring vessel 24 by means of suitable hoses which can be conveniently attached or detached to allow transportation of the SBS Unit 22. Each of these ports (herein after termed a supply port) is dedicated to the supply of only one fluid such that supply port 132 is dedicated to attachment to the suction pump 27, the supply ports 133 and 134 are both dedicated to the attachment of the external measuring vessel 24, the supply port 135 is dedicated to connection to the nutrient source and the supply port 136 is dedicated to the attachment of the high pressure air supply form the compressor 23.

Fig 2A shows a single stage lance 30, made of tubing of a diameter of approximately 15 20 mm and of sufficient thickness and substance of sufficient strength to withstand the operating pressures of the system and to withstand the stress of installation however that may be accomplished. The lance 30 is made in sections comprising an outlet section 31 and tubular extensions which may have male and female threads cut into them 33,34. At the top of the lance 30 a connector compatible with high pressure air hose is fitted.

The outlet region of the outlet section has side outlets drilled radially to the central axis of the length of the tube. Typically it would have three holes drilled around the circumference of the tube 1200 apart. Those holes would each be of the order of 2-5 mm in diameter dependant upon site specific design related to the depth, density permeability and porosity of the soil and the spacing of the lances. There would typically be twelve rows of these holes each set equidistantly from its neighbour which distance would typically be of the order of 5 cms. between rows. Each row would be offset 100 in a particular direction from the row before. In use, the fluid flows horizontally over a predetermined range of depths.

An outlet section 31 may also be a boring section with an additional outlet 37 formed in the end of the tube 3. The outlet 37 is made slightly smaller than the internal diameter of the lance 30 by swaging or other means to create a slight restriction but the outlet 37 is considerably larger than individual outlets 36.

To drill the lance into the site compressed air is blown through the outlet at sufficient pressure , typically 1.5 mPa, which has the effect of displacing the soil immediately in front of the outlet 37. When the lance has been inserted to sufficient depth, a ball bearing or other spherical object 38 of sufficient substance and size is inserted at the end of the lance tube 30 above the surface of the soil 10 and pressed to the outlet end 37 of the tube 31 under the influence of high pressure gas, thus sealing the outlet 37 With the outlet 37 sealed the lance is thus relieved of any vertical reaction forces created by the high pressure gas and all materials flowing through the lance 30 are diverted to flow through the outlets 36 which have been bored radially to the long axis of the lance 30.This has the advantage over multiple stage lances 50, in that multiple stage lances need to be at least partially drilled into the soil.

Single stage lances can be used singly, or in pairs, or in more complex arrangements to provide the appropriate coverage of several depths.

The Lance 30 of Fig 2A is sealed to the ground surface by passing it through a locking tube 40 in a ground sealing plate 41. The lance 30 is secured in the locking tube with a locking bolt 42. The sealing plate 41 is secured to the surface of the soil with a large diameter tube 43, typically 100mm in diameter and 100mm long, which is welded at one end to the underside of the sealing plate 41 and provided with a chisel edge at the other end which is pressed into the soil, as shown in Fig 2B.

Alternatively a two stage lance 50 as shown in Fig 3A may be used. Two stage lances are useful in event of emergency or for treating spills which lie close to the surface (within 2-3 metres) of the soil and where a semi-permanent installation is not required. They are reusable but their use is labour intensive.

A Multiple stage lance 50 comprises an upper region 51 and a lower outlet region 52 and may additionally have several intermediate outlet regions (not shown) each of which is hereinafter termed "a stage".. In the two stage design illustrated, the upper outlet region 51 is a canister (typically of 2 mm thick mild steel) approximately 50 mm in diameter, and the lower outlet region is a pipe (typically of mild steel) of approximately 20 mm diameter The upper stage is made as long as necessary, dependant on the depth of the plume of pollution, the porosity of the soil and the radius of lance influence 145 but the length is a compromise with other factors, such as the need to be portable and the fact that fluids will be blown out of this and every other stage under the influence of compressed air and may also be pulled through the soil by suction delivered from other lances and all will be effective provided that the radii of influence intersect.

A typical length for a unit which is manhandleable would be from 300 mm to 1000 mm excluding the length of the extension lance to the lower stage 52 and the handle 54. The upper stage is connected to a lance-hose 28 via an inlet pipe 56 which openly discharges within the upper stage canister within approximately 30 mm from the bottom of the canister to facilitate the removal of fluids sucked into the canister when the stage is used in a suction mode. The inlet tube is evenly deformed at the other end to provide a lip over which the hose 28 is forced so that a jubilee clip may used to fasten the hose to the inlet tube 56 and yet be retained in position when the hose is under internal pressure form the compressed air passed through it.A drain point of small diameter (typically 2mm) is provided in the bottom if the canister to ensure that all fluids can be discharged from the canister during use.

The lower lance 49 is screwed into a threaded boss 58 on the bottom of the upper stage. The connection to the hose inlet attachment 55 is by a slender pipe (typically mild steel tube 12 mm in diameter) running through the upper stage and welded into the boss 58 at one end.

The other end of the inlet pipe 55 is evenly deformed to form a pipe securing lip in similar manner as for the hose attachment end of the inlet pipe 56.

The pipe forming the lower stage is cut to length to suit site specific requirements having regard to the depth of the water table, the position of the plume of contamination 14 and the radius of lance influence herein after termed " site specific factors".

The depth at which the upper stage is positioned within the ground will also be a compromise of site specific factors and will require an adjustable means of positive positioning in the vertical plane. Therefore a handle 54 composed of drain rods is attached to the central position of the top of the canister. These may be extended in one metre increments.

When holes drilled in the soil an left unsupported there is often a tendency for the sides to collapse or distort under the pressure of the earth around the sides of the hole. They can also be difficult to locate without there being some form of visual marker. Additionally multiple stage lances 50 which are re-used require sealing to the ground surface to prevent the escape of treatment fluids by what is effectively a short cut up the sides of the lance and thence to the surface of the soil. Fig 3B details a means of overcoming these three separate issues with one common technique. The sides of the hole drilled into the soil is supported with a length of pipe 57 of a durable material of sufficient strength and suitable diameter.

Typically 62 mm PVC rainwater pipe may be used for this purpose. Such pipe may be inserted in lengths cut to suit site specific factors terminating at a point close to the desired outlet the first stage below ground level of a multiple stage lance 50. Such pipes may be moved sequentially from treatment block to treatment block but would more usually be left in position. The multiple stage lances 50 may now be inserted and are sealed to the plastic bore liners 57 by a sealing ring of rubber or similar synthetic material 53 clamped to the top of the canister of the upper stage by a metal clamping ring 48 screwed into position.. This arrangement allows the lance to be withdrawn for re-use in an alternative treatment block 21.

The spacing of lances is dependant upon the radii of lance influence. Whilst there are ways of calculating this by formulae using data from the results of known tests there is a need for positive identification and this may be discovered by execution of a test shown in Fig 11 where by a test lance 180 composed of galvanised iron pipe of approximately 15 mm internal diameter screwed together with a standard air line bayonet connector 183 affixed to an end at right angles to the main lance iube to prevent torture of the airline whilst in use and with a plugged tee 182 in the end of the tube to allow access for later cleanir.g Another branch 181 to the main pipe 180 is provide some 300 mm away from the air hose tee fitting 182.This branch 181, 188 terminates in another four way branch fitting 184 from a reducer 188 to allow the fitting 184 to be of approximately 30 mm nominal bore.

The three open ends 185,186,187 of this four way fitting are sealed with standard iron plugs. One of these plugs shall be drilled out to accept stout steel electrical conductors 191 in a heat-proof insulator. With the electrical conductors and relevant plugs in place the third plug is removed to allow a loose plug of fine wire wool 192 is placed in contact with the two electrodes A standard drains testing smoke pellet 190 is placed amongst the wire wool and the third plug 187 replaced to seal the equipment. When used the smoke test reveals the extent of lance influence and the speed of travel of compressed at across the site.

The SBS Unit 22, controls the selective distribution of treatment fluids (including suction) to and from the appropriate lances 20 in the array of lances. Those treatment fluids are compressed air, nutrients, suction of air and materials and other chemicals.

To keep the design compact and avoid the need for further pumps, the treatment fluids are drawn into the SBS Unit 22 by flowing through an initial network of pipes shown in Fig 4.

Operation of valves upon the network 60 in fig 4 and any other internal valving arrangement within the SBS Unit 22 is achieved by computer control of electro-pneumatic or electro mechanical valves The sources of the fluids are connected by hose to the SBS unit upon following connectors mounted upon the SBS Unit.

Connection Fluid resource and flow direction Source and now path Number 132 suction pump 27 direct to connection 132 133 Suction from or high pressure gas into Suction pump 27 via valve 65 and 64 or the external measuring tank 24 compressed air from compressor 23 via valves 61, 62 & 64 134 Fluid inflow to SBS unit reservoir and Nutrient barrel or bowser 25 via the internal distribution system. Nutrient flows reservoir 77 or the non return valve 71 within from the external measuring tank 24 the SBS Unit 22 135 Nutrient or other liquid inwards to From Nutrient supply 25 SBS Unit 22 136 Compressed air inwards to SBS Unit From Air compressor 23 22 During the operation of the present configuration of an SBS Unit fluid resources are drawn through a hose to connection 135 and thence through a non return valve 72 into a measuring vessel of fixed volume 77 under the influence of suction form the external suction pump 27 via the pneumatically operated three port ball valves 65 and 64. Where ball valve 64 is turned to open towards port 133 that same suction is applied to the external measuring vessel 24 and fluid simultaneously flows into the external measuring vessel 24 via non return valve 71 at the same time as it is drawn into the internal measuring vessel 77. via non return valve 72 Due to level difference the vessel 77 will fill later than the measuring vessel 24. since suction from valve 65 is applied to the top of the vessel 77 and is above the top of the external meansuring vessel 24. Meanwhile (for the purpose of this example) valve 61 is open and high pressure air is flowing through valve 62 to valve 63 and thence to the distribution pipe 86.

Once the vessel 77 is full this is sensed by the level sensor 76 which sends a signal to the computer 103. The computer now switches off the pump and turns the valves 65 to its alternative position. Valve 64 is left with an open path towards the closed aspect of valve 65 but remains open via the branch pipe shown to the top of vessel 77. and thence to the closed aspect of valve 62.

Now the computer turns valve 62 to open towards the vessel 77 and away from valve 63.

High pressure air is now forced into top of the vessel 77 and the top of external measuring vessel 24 creating a piston effect within both vessels. Fluid within vessel 77 is now forced out through a bottom connection on vessel 77 through non return valve 74 and thence to the distribution pipe 86. Fluid in the external measuring vessel 24 is also forced out via non return valve 73 and then through non return valve 74 thence to the distribution pipe 86.

The non return valve 71 prevents fluid ejected from the external measuring vessel 24 being forced back to the supply point 25 and the non return valve 72 prevents fluid ejected from the internal vessel 77 being forced back to the supply point 25. The non return valve 73 prevents fluid ejected from the internal vessel 77 from being forced back to the external measuring vessel 24. When the vessel 77 is empty the measuring vessel 24 is also as empty as it can be depending upon its level positioning. Efficiency here depends upon positioning the floor of the measuring vessel 24 to be slightly higher than the floor of the vessel 77.

The opening into the top of the vessel 77 is also restricted such that there is less air flowing into vessel 77 than into measuring vessel 24 ensuring a swifter emptying of measuring vessel 24 which is required since measuring vessel 24 is much larger than vessel 77. The height of measuring vessel 24 is always less than the height of vessel 77 such that the floor of 24 can be at a level above the floor of 77 yet the ceiling of 24 is never as high as the ceiling of 77 where it is connected to the air supply.

As soon as vessel 77 is empty the level sensor 76 reports this to the computer which now proceeds to the next part of its programme.

The computer now operates valve 62 to supply valve 63. Valve 63 continues to supply compressed air to the distribution pipe 86 which forces the fluid outward through the remainder of the system, which is later described, and thence to the appropriate lance or group of lances. At the same time the computer switches valve 65 to suction from pump 27 which begins to refill the vessels 24 and 77 to supply another charge of fluid to the appropriate lance or group of lances.

In the present embodiment the SBS Unit 22 has thirty two lance ports, which are capable of serving, for example, sixteen two stage lances. There is one additional port 79 dedicated to a suction action only and this is exclusively used to drain any centre bore 146 of any treatment block 21.

If a small system of thirty three such ports was to be arranged such that all treatment fluids and suction (hereinafter described as "resources") were to be made instantly available to all lance stages then the SBS system would become unwieldy and not suitable for use within buildings or other places featuring difficult access. Accordingly there is a need to subdivide the network into smaller groupings of lance ports to which a particular resource can be commonly supplied at any given time without influencing any other such branch or grouping of lance ports 84.

Moreover, it is essential, to the system of proposed treatment, that the system has the capability to create regions of different pressure within a treatment block 21. Such pressure regions can be created using an array of lances within a treatment block 21 as in Fig 1A where sixteen lances lettered A-P are set out in an array of two concentric square. The outer square has twelve lances whilst the inner square has four lances. In such a system of sixteen two stage lances the first stage is displaced above the second and deeper stage by an amount based and calculated upon the radii of influence 145 of the lances 20.Such a configuration generates four identifiable squares of lances (herein after termed "frames" which can each be separately identified and named as upper outer, upper inner, lower outer, lower inner. or in the alternative Outer stage 1 Inner stage 1, Outer stage 2, Inner stage 2. These squares are an effective basis upon which to subdivide the treatment pattern and about which to create the desired regions of differential pressure Consequently they are an effective basis upon which to sub-divide the network The valving is thus much reduced and the internal distribution system of the present configurations of an SBS Unit 22 are sub-divided to reflect that pattern of four displaced or concentric squares within the treatment block.This sub division is reflected in the branch subdivisions 80,81,82,83 of Fig 5C and the four separate plenum chambers 159 of the newly envisaged discvalve block 150 in Fig. 6C.

Fig SC is a schematic embodiment of the general internal pipe layout forming the piped distribution network (connected to and following on from the induction network shown in fig 4) of an SBS Unit 22 of the type shown in Fig 5A and also shown in sectional view in fig 5B.

In this present configuration the distribution pipe 86 is reserved for the dispensing of fluids, the distribution pipe 85 is reserved for the supply of suction. The pipe 86 is isolated from any branch containing any outlet ports by four independently operable valve 88 and similarly the distribution pipe 85 is isolated from any branch containing any outlet ports by four independently operable valve 87 When it is required that either a fluid or suction are required within any particular frame 147, or 148 within an array of lances 20 forming a treatment block 21 the appropriate isolation valve 87 or 88 is opened to allow that required resource to flow into the branch serving the appropriate group of lance ports within the array.Flow from the branch to a particular lance is controlled by manipulation of an electro-mechanical or pneumatic valve directly controlling each individual lance port 84 In the present configuration the distribution pipes 85 and 86 and the branch pipes 80, 81,82,83 are all 32 mm internal diameter of copper or ABS plastic.

In order to keep the weight of the machine to manageable and manhandleable proportions it is essential that the weight of the lance port valves is reduced to a minimum. But an industry standard valve weighs about 1.2 kg. and Fig 5D shows the arrangement of a newly envisage lightweight valve Those valves 90 constructed in ABS weigh approximately 10 grams each. They are constructed from known components being standard pitcher tees end caps and reducers to form the body 90 leading from the branch 80,81,82,83 to a connector to external hose 84. The valve is operated by the application of pneumatic pressure to a double acting cylinder 93 having a piston rod 92 of sufficient length of thrust to cross the depth between the end cap and the face of the reducer where it restricts the orifice of the the pitcher tee 90.The rod 92 also supports a sealing member 91 composed of a 28mm diameter stainless steel washer of 3 mm thickness supporting a stout neoprene or plastic or rubber or syntheic rubber washer all held in place by two stainless steel nuts tightened against each face to secure the assembly upon the threaded end of the piston rod 92.

The valves 90 are normally maintained in the closed position (not allowing fluid to pass to or from the lance) by the application of compressed air (hereinafter termed the "control air") which is obtained from an air reservoir 99 via a pressure regulating device 97 which allows the air in the tube 95 to be maintained at a constant pressure of about 800 kPa by a regulator 97. This air is applied to the plain face of the piston (without any rod protruding) which face has a known area and therefore creates a known force. The control air supply is itself controlled by a known electro-mechanical 3 port normally open 3/2 pneumatic valve 98 positioned within the airline 95 and venting to outlet 75.

Air pressure is also applied to the 'rod face' of the piston in the pneumatic cylinder 93 and this is also obtained from the air reservoir 99. This air is controlled by regulator 96 and constantly supplied to the pneumatic cylinder 93 at a pressure of 700 kPa. to provide a continuing withdrawal force upon the piston and the valve sealing assembly 91, 92, which pressure is herein after termed 'spring air'.

When the computer programme requires the valve 90 to open it delivers a direct 24 volt signal from within itself to the appropriate solenoid valve in the array of solenoid valves 98 there being one such solenoid valve and airline assembly for each such valve within the SBS Unit 22. The effect of this signal is to operated the solenoid closing off the control air to the pneumatic cylinder 93 and venting the line 95 lying between the valve 98 and the pneumatic cylinder 93 to vent 75 The piston and rod 92 in the pneumatic cylinder 93 now withdraws under the influence of the spring air so apening the vales to alow air flow from the barcnches 80,81,82 or 83 to the lances 20 by means of hoses 28.

The air pressure within the branches 80,81,82,83 can be at substantial and equal to that of the compressor output at 1 mPa if all outlets are closed, but tests demonstrate that the usual back pressure during treatment is in the region of only 80 - 100 kPa Accordingly a 10 mm pneumatic cylinder will achieve operation of the lance port valves 90 provided that the computer programme arranges for one valve 90 to open before the previously opened valve is closed. In this manner there is at least one lance discharging to the ground at any given time ensuring that the backpressure is at or below 100 kPa. This can be achieved in the programming with a programme script known as a cut throat timer and this can be applied to a cascade of valves opening and closing in sequence.In the event that the backpressure is too great for the valev to open then the main air valve 61 is operated to interrupt the flow and the computer programme is written to fail safe in this regard.

Air for both spring air and control air systems is obtained via pressure regulators 96 or 97 from an air supply reservoir 99. The reservoir 99 obtains its supply of air from an known air straining and lubricating set 101. The air straining and lubricating set obtains its supply of compressed air from a branch off the the main incoming airline 86 which branch is connected at a point upon the distribution pipe 86 lying between supply port 136 and the main air service shut of valve 61. The air is then ducted via a regulating valve 107 which maintains the air pressure at not more than 1 mPa through a non return valve 102 before entering the reservoir 99.

The reservoir 99 is fitted with a pressure sensor attuned to both the required maximum and the required minimum reservoir air pressure. It is a known device capable of emitting a signal upon pressure falling to a minimum and emitting a different signal upon pressure reaching a maximum. These signals are supplied to the computer 103 by cable 104 and 108.

Upon receiving a signal indicating that pressure in the reservoir has fallen below the minimum threshold then the computer halts the main programme and closes the main compressed air shut off valve 61 by signal through cable 105. Since the compressor is shutr of from ay other part of the system by valve 61 it delivers air at full compressor pressure (which is a higher pressure than the upper limit in the reservoir 99) and since the ambient pressure within the reservoir is now at or below the pressure of the lower limit in the reservoir 99 the available air is now fed into the reservoir 99 via the regulator 107, non return valve 102, and the air strainer and lubricator 101 to the maximum pressure allowed by the regulator 107.

Upon the reservoir reaching the required pressure the sensor 100 issues a signal indicating maximum pressure has been detected and the computer 103 now open valve 61 and allows the main programme to resume from the point where it was halted. The pressure in the distribution pipe 86 now falls below the pressure in the reservoir. This pressure is retained in the reservoir by the non-return valve 107. As the air pressure a the regulator 107 is now higher on the reservoir suide than on the supply side no further air can flow into the reservoir and will not do so until more of that air has been expended operating the valves in the SBS Unit 22 internal systems An alternative embodiment of the distribution system will now be described. In order to achieve the groupings a new valving device has been conceived and is termed the disc valve 150.To accommodate four fences within the treatment block 21 four separate discvalves 155 in four separate plenum chambers 159 are set into a single block 150 of non corrodable metal or high strength plastic (with or without stailess steel liners) which forms the heart of the SBS Unit distribution system.

Each discvalve shown in Fig 6C and 6D consists of a circular plate 155 within a plenum chamber 159. There are two inlets ports 152, 156 to each plenum chamber 159, one is for suction and the other for fluids including compressed air and nutrients. These inlets are connected to the distribution pipes 85 for suction and 86 for fluids emanating from the induction pipe network in Fig 4. The flow of each resource into the plenum chamber is controlled by a separate shut off valve for each supply 87 for suction or 88 for fluids and those valves shall serve only one discvalve with a block of discvalves. The disc is a circular metal plate 155 with shaped synthetic rubber, or plastic or neoprene stoppers 154 which fit the output positions 157 irrespective of the position to which the disc is rotated. There is an area of the plate cut away 153 so that there is no "stopper".Extra outlet points 161 are fitted as spares and blanked of as "Stopall" positions When the programme requires a disc valve to operate, the resource flow is interrupted by a valve 87 or a valve 88. The disc 155 is lifted of its seating either by electro magnet 160 or a pneumatic piston. It is rotated to the desired position by a stepper motor and gearbox 159 and re-seated by the electro magnet or pneumatic cylinder 160. If the programme calls for all ports within a frame to be opened simultaneously the disc 155 is lifted clear of it seating by the electro magnet or pneumatic piston 160 for the desired length of time as determined by the computer programme. The Plenum chamber has a shelf 166 beyond which the plate 155 travels away from its seating, allowir,g resources to flow evenly around the plate.To allow the stepper motor gear and the electro magnet or pneumatic cylinder to work together the centre boss 158 of the disc plate 155 is manufactured as a female splined orifice into which the male splined shaft, being the final output of the stepper motor gear box, can be inserted.

The Fig 6a shows the exterior of an SBS unit configured to utilise a discvalve system.

There are a plurality of ways of configuring the output pattern to ensure consistency and accuracy of site connection.

Fig 6B shows a schematic cross section of an SBS Unit 22, embodying a discvalve system.

The induction pipe network and fluid measuring vessels 24 and 77 shown in fig 4 will be required whichever embodiment of the SBS Unit 22 is considered but the outlet valves 90 and supporting pneumatic system would not be necessary. However the newly envisaged SBS Unit employing a Discvalve would require an air reservoir 99 and supporting system of strainer lubricator 101, non return valve 102, pressure regulator 107, pressure sensor 100, main air shut off valve 61, air line 86 and connector 136 plus the computer 103, and cables 105 andl04 and 108 The computer could have a reduced memory capacity and if using a programmable logical controller may not require a memory extension unit. Internal supply pipe within the network after the discvalves may, if desired, be constructed of reinforced plastic air hose line.

Where a discvalve system is used then further compactness may be achieve by arranging for the fluid measuring cylinder and / or the air reservoir to rise through the centre of the plate.

The SBS Unit requires and electrical supply from an external source, typically a 110v supply either transformed from a mains supply or from a smoothed site generated supply.

The electrical connection 138 is dedicated to connection to a means of reasonably smooth electrical power from an external source 131. Where there is no alternative but to use site generated electrical power a means of smoothing the supply must also be provided which device which may be external or internal to the SBS Unit 22 and its casing 125. An unsmoothed supply from a generator is not usually suitable as it is incompatible with the operation of most computers.

Each SBS Unit 22 requires an internal waterproof electrical compartment 120 The computer 103 can be separately placed as can the array of solenoid valves 98 which lie at the heart of the pneumatic valve control system. Such an array 98 will not be required in an SBS Unit 22, as shown in Fig 6A 6B, 6C, 6D, where such a unit is controlled by the sole use of electromagnetic equipment.

An electrical transformer 121 is provided to reduce the voltage to 24 volts. Means of rectifying the current to 24 volts DC are also incorporated to be compatible with a variety of relay and computer systems. Such systems need to be selected to be of sufficient robustness to withstand site shock. The Mitsubishi F1 Programmable Logical Controller which was selected for the prototype SBS Unit using Melsoc Medoc software for programming purposes. The computer language used in the prototype is known as 'Ladder'.

The SBS Unit 22 is provided with an electrical relay 122 operating at 24 volts and delivering 130 volts. This is provided to allow the computer to control the actions of the external suction pump 27. The pump 27 is connected by its own electrical supply lead through a splash proof connection 137 upon the SBS Unit 22.

A start button 139 is required to enable a operative to initiate a treatment cycle and such a button is inserted into a circuit operating at 24 volts by which means an initial input signal may be delivered to the computer so to commence the programme.

Each connection from an output terminal or input terminal upon the Programmable Logical Controller must be properly terminated and bound in a loom to carry signals from the input sensors and controls to the computer and from the computer to solenoid control valves and or other electro-magnetic or electro-mechanical equipment within the casing 125 of the SBS Unit 22 There must be provide an emergency stop button 140 which can be lockable for security reasons. The emergency stop is installed in the circuitry to cut off the 1 10v supply immediately inside the electrical compartment Optionally a rotating light beacon or air horn can be fitted to indicate completion of a cycle Instrumentation is relatively simple with much reliance being placed upon the computer to cater for events and quality control.

Instrumentation may incorporate a number of pressure gauges to register internal operating pressures within the reservoir, the main network, the control air supply or the spring air supply. Similarly pressure gauges might be installed within the suction section of the network to indicate pressure reductions achieved.

Two counters 123 are always provided which counters may be separately incremented by the computer. One counter is used to measure successful programmes the other to measure the number of nutrient discharges accomplished.

The timing of all actions is dependant upon internal clock mechanism and the 'timers and or counters' made available within the computer programme.

A description of initial site investigations and their effect will now be described.

Following initial inspection samples of soil taken from the site are subjected to a bio-assay and soils laboratory testing to BS 1377 part 6, in order to produce a map of the site, its topography, soils profile and the contaminant plume.

The soils tests will crucially reveal the Voids Ratio of the soil from which the amount of free air space within a treatment block 21 can be calculated. The amount of air one can exchange within a treatment block is a measure of the amount of oxygen which the soil can accept in any single treatment (hereinafter termed a "pass") The amount of available oxygen usually determines the mass of contaminant which can be metabolised as a result of a single treatment pass. This in turn determines the amount of balancing nutrients which are required at any single pass.

The soil tests will, additionally, reveal saturated density and dry mass soil classification particle size moisture content limits hydraulic gradient, permeability and porosity from which the radii of influence may be calculated from known formulae or adaptations thereof.

In the alternative the radii of lance influence may next be discovered by execution of a test using a simple pipe system shown in Fig 11 The three open ends of this four way fitting are sealed with standard iron plugs. With the electrical conductors and relevant plugs in place the third plug is removed to allow a loose plug of fine wire wool is placed in contact with the two electrodes A standard drains testing smoke pellet is placed amongst the wire wool and the third plug replaced to seal the equipment. The airline is now attached at connection 183 and the lance inserted into the ground under the influence of comprtessed air 'drilling' to the find the depth specified for each test. The air is allowed flow at full pressure for about a minute.The ground is now usually cracked to its practical limit in respect of the immediate impact and effective lance influence will have been reached.

With the compressed air still flowing the electrodes 189 are now connected to a 12 volt battery. The electrical flow will treat the wire wool as a resistance and it will heat it to the point where it will effectively burn. This will ignite the smoke pellet which will in its turn produce about 85 cubic metres of smoke. . The smoke will be drawn into the air flow and injected into the ground at the design depth. The smoke will ultimately issue from the surface of the soil.

The moment of ignition is timed and recorded and the following events are also timed and recorded The timing of the first sight should be recorded. The smoke will continue to issue forth from the soil at greater and greater radii from the lances tube. The rate of increase in distance over time may he measured and recorded at 1 minute intervals until the last trace of smoke disappear. The data so revealed can then be analysed to indicate the radii of influence as well as the speed of delivery and transmission through the ground. From this test a practical observation can be made and that data can be compared to data generated by formulae resulting from laboratory soils tests. These comparisons will enable site specific correction factors to be evaluated for future reference.

Using all of this data and knowing the average concentration of a particular contaminant within a treatment block, it is possible to at least estimate the minimum number of passes which will be required, to clear the pollutant to the acceptable level laid down by the regulatory authorities. The size of and severity of the plume having been discovered during the early survey work, the minimum time and cost of treatment of the plume can now be assessed. The amount of nutrient required can also be estimated and checked against the proposed number of passes to ensure that any single treatment in any pass will not breach authoritative limits nor limits upon concentration of nutrients in any innoculum. Beyond such levels it is possible to harm the very micro-organisms the system hopes to exploit.

A description of the issues raised in protocol design will now be described.

Optimising the development of the population of soil resident microbes by making that population 'comfortable' is the essence of bio-remediation.

It is known that bio-remediation is not successful with some contaminants where the concentration of contaminatipn in the soil is overwhelming. For example hydrocarbon pollution of greater than about 5% by dry weight of soil is often toxic to the microbes expected to metabolise it. Similarly nitrates although they are a principle nutrient resource required by the microbes, innoculum strengths containing nitrates at concentrations greater than 300 part per million can have a toxic effect upon the microbial poulation. Too much nitrate can also breach permitted ground water and drinking water limits.

Accordingly care must be taken to prepare the polluted soil by in a number of ways. The principal method is the physical removal of the free-phase (free running) pollutants before remediation can start. This can be achieved by direct pumping, soils massage and leaching with an innocuous fluid such as plain water. Chemical including surfactants can also be infused if so desired to aid leaching . The soil may also be heated by pre-heating the compressed air which is also used as the principal physical force and the principal aeration agent within the SBS System The best microbial populations for use in bio-remediation are the indigenous populations since they are acclimatised to site specific factors and have developed a tolerance of local site conditions which an augmenting microbial population may not pcssess.Nevertheless the SBS Close Lance System. is capable of deploying such imported micro-organisms where necessary by substituting those micro-organisms in a carrier fluid and dispensing them in the same manner as nutrients Whichever microbes are employed, whilst they are very tolerant of some extremes (particularly pressure) they clearly have preferred environments and it has been shown by experiments in America that a pH level of 7.2 is most favourable. The soil pH levels can be adjusted by the infusion of certain chemicals not least a suspension of hydrated lime in water on acidic soils. Again such fluids can be dispensed in the same manner as nutrients Temperature is also an important factor and it is possible to heat the air before it is infused.

Figs 10 and 11 show a means 221 whereby the waste heat from an enclosed compressor 23 In this embodiment the air compressor is electrcially driven and rated at 55 kW to produce 0..2 cubic metres of air per second at 1mPa. The waste heat from the compressor amounts to 85% of the nominal input energy and raises the air temperature by 170C. This waste heat can be ducted through a heat exchanger over a heating coil mounted after the compressor output. can be used to pre-heat the air after it has been compressed. Essentially this is a coil of SOrnm galvanised iron piping in a 'coil' composed of stright pipe and elebows screwed together. It is atached to the output of the compressor since the ingoing air must be cool to avoid the compressor shutting down due to thermal overload.

The hot air flow remaining can then be ducted around the water recycling tanks 202, (aerated cleaned water) 203 (water settlement tank) 204 (oil separation tank), and the nutrient mixing bath 205 in order to raise the temperature of those facilities and promote microbial growth within the innoculums whilst they are being stored prior to use.

Soil moisture content is another factor and again experiments in America have shown that a soils moisture content of 15% by weight is conducive even optimal for microbial activity.

'Soils massage' can be utilised to drive out groundwater and coupled with regular site pumping can successfully reduce the moisture content where necessary.

The compressed air also provides oxygen to newly fractured ground and this provides an enhanced source of oxygen. A saturated site exhibits oxygen concentrations of only 8 part per million. Aerated water will provide 50 ppm. Oxygenated water 80-100 ppm.

Hydrogen peroxide has also been used in the prior art but has been found to cause pore clogging (Moragn and Watson 1991) and be ineffective in many cases. Plain air contains 21% oxygen or over 200,000 part per million and pore clogging is abated as airways are kept clear.

The oxygen in the air will allow the aerobic microbial population to metabolise contaminants. It is already known that for example oil requires oxygen at a ratio of 3.1 to 1 by weight to permit metabolisation. In other words it takes 3.1 grams of oxygen to allow the microbial population to metabolise 1 gram of oil. Similarly nutrients such as nitrates are required at ratios of 1 to 160 where 1 gram of nitrate will support the microbial metabolisation of 160 grams of oil. An amount of phosphate, sulphates and trace elements are also required and specialist companies have developed such nutrient materials, However it has been found that some commercially available liquid fertilisers are just as effective in practice and cost less.

The next decision is how long a time each 'treatment pass' should take. The amount of time spent infusing air into a treatment block 21 is a function of the size of the treatment block and its voids ratio. Such volumes can be delivered very swiftly and the critical issue is therefore not just how swiftly one can infuse sufficient air to replace all of the existing soil gases within the accessible voids. but how quickly the air can penetrate the macro and micro pores in those blocks of soil left in homogenous sections between the preferential pathways the air blast have created As the breaking up of soil with compressed air is not part of the prior art of bio-remediation there is no clear data on the subject although it is clear that it works.

One of the discoveries leading to the present application is the discovery by the inventor that ground water and free phase contaminants are also displaced by high pressure air injected directly into the soil and where a ring of such lances are set to discharge simultaneously they have the effect of squeezing polluted water out of the ground (hereinafter termed soils massage) and directing it to extraction points from which it can be recovered by way of the extraction port 79 on the SBS Unit 22. The collection of such fluids is one of the reasons for the use of a central bore 146 within a treatment block 21 The subject of laminar flows through packed media is a documented subject dating back to Darcy (1858) and then to Kozeny (1925) and to Carmen who published a paper on air flows through packed media in 1985. However there is nothing found on turbulent flow in air fractured soil.

Nevertheless a research paper by Dineen, Slater, Hicks, Holland, and Clendening (page 177 in Kostecki and Calabrese Petroleum Contaminated Soils Volume 3 ) shows that in their experiments they used 50 feet deep wells with air at only 3.5 psi or 25 kPa, (as opposed to close spaced lances working initially at 1 mPa). They reported breakthrough speeds in the macro pores of 0.8 cms per second and in the micro pores 0.006 cms per second. They claimed their results compared well with Hazen's equation which would suggest they were working with relatively sandy soil since Hazen's equation is not suitable for application to clay soils.If one assesses the speed of air through such micro pores then at 100 kPa over 300 mm then it would suggest that the application of that pressure for 20-30 minutes would achieve a reasonable penetration and Dineen et al. reported that a significant proportion of the air delivered passed in that time but it took much longer to pass all of it..

Nutrients are fed to the site in measured quantity diluted in a carrier fluid most often recycled groundwater recovered from boreholes 146 and thence filtered or allowed to settle for a specified period. Where there is no groundwater to recover or recycle then there would be a need to use activated carbon filters to remove chlorine from any imported water before use in an innoculum.

Any nutrient (or leaching fluid or chemical or surfactant) required is forced through the site under the influence of high pressure gas (usually compressed air) which insures complete treatment of all parts of a polluted site. The ability to deliver such moisture is another novel feature of SBS Close Lance System since no other known system in the prior art has the capacity to positively deliver such moisture to all parts of a dry site.

The next decision is how long should be left between passes. Each treatment 'pass' delivers a set amount of oxygen and nutrients sufficient to 'slice' a portion of pollution away. A critical issue is determining the frequency of passes or the time span left between treatments. It is clear that this is a function of the speed with which the micro-organisms metabolise the oxygen supplied and it is a dynamic value which changes as the population of soil resident micro-organisms develops. And that population will grow exponentially provided always that it has sufficient nutrition freely available and it is in other ways (and for the want of a better word) comfortable.

A protocol is now calculated and transcribed into a programme suitable for use in the choice of computer used in the SBS Unit available whichever embodiment it might be. Part of that protocol will also refer to the radii of lance influence, (derived from site test or calculated from the soils laboratory results). The size of treatment block 21 is then established from a formula and transferred to a setting out drawing of the site drawn to scale.

The calculation procedure is best done by a short computer programme which will calculate from the data, the size of treatment block, the maximum volume of nutrient fluid to be injected, the time that the compressed air is likely to take to spread to all soil volumes within the treatment block 21 and the number of nutrient injections needed having regard to the size of external measuring vessel 24 which can be made available. The aim of the programmer is to limit the programme to about half an hour such that sixteen to twenty treatment passes might be accomplished within a working day.

The size of the contaminant plume 14 will have been established from site survey and thus the number of treatment blocks will be known. The amount of nutrient to be injected will limited by maximum permitted concentration and this is likely to be the limiting factor in determining the amount of pollution one expects to "slice off' at each pass. Since the concentration of contamination is known, or can be interpolated for each block, the minimum number of passes can be estimated and this estimate can be translated into a minimum overall period of treatment. The reason for the estimate beoing a minmium treatment period is that the actual vigourt of the microbial population will not become wholly apparent for a some time.

A known test can be conducted in the laboratory to indicate oxygen demand which in turn will indicate the extent of microbial activity and from thence the ideal time to be allowed between passes or 'dwell time'. The actual 'dwell time' will be a compromise with other factors not least the availability of machinery and resources.

All of this information is written to a formal protocol and example of which is shown in Table 2.

A description of the method of application will now be described.

By reference to the protocol ands site plan the site is marked out in a regular grid to reflect the protocol The lances 20 are installed to reach the plume of contamination 14. Fig. 7 illustrates the cross section on a pollution field where multiple single stages lances 30 are employed to form a multi-stage access to the plume 14. Such configurations are site specific but could be more regular in depth with a uniform programme or they can have an irregular lance format with a more regular programme which accounts for the characteristics of each treatment block 21.

The lances 20 are connected to the appropriate SBS unit lance-ports 84 by hoses 28 which may be wire reinforced PVC hose or nylon braided hose sufficient to withstand the maximum operating pressures of the system and of sufficient internal diameter to (being a minimum of 12 mm) to be compatible with the designed delivery speed of the protocol and the programme. Connections to the lances shall be by jubilee clip or similar device.

The supply port connections 132,133,134,135,136, shall be byknown high pressure air hose or braided or wire reinforced PVC hose where appropriate. All hose connections to the SBS unit shall be industry standard bayonet or plug in connections. They may be configured with the ends on certain hose to be compatible or mutually exclusive so as to reduce the opportunity for error upon connection.

There will be a case for implementing an in-line extension system with quick release connections to assist with speed of manual site movement of the SBS Unit.

For swiftness of use in a manual or free-phase operation two sets of re-usable lances 20 may be employed. to allow one treatment block to be prepared whilst another is being treated. Alternatively standard copper pipe to BS 2781 table X or similar may be used in the manner of lances 30 to create a treatment volume which is permanently or semipermanently installed to allow for repeated treatments or passes over a period of time.

Figure 8 shows a layout of an array of lances 20, which are arranged in "close formation" Fig 8 also indicates the lines of the outer frames 148, and the inner frames 147, the areas of overlap where radii of influence intersect 149. The size of the treatment block 21 both on plan and in depth is dependant upon the radii of influence 145 A treatment block 21 may also be centred upon a central pumping bore 146 into which ground water may be moved under the influence of compressed gas or air administered through the lances 20 in groupings denoted by the frames 148 and 147.

The SBS Unit will in each and every case follow the precise instruction of the computer in the SBS Unit 22. Those instructions will initially seek to clear each lance and to recover any free flowing ground water from each outlet region of each lance and suction is applied 'lance by lance' and 'frame by frame' so that a relatively small pump may be used and shared by each outlet region. Applying a particular resource to each lance sequentially or lance by lance is hereinafter termed a 'cascade' The next action is with a short blast of air using the whole of the compressor capacity and power concentrated upon a single lance in turn in a cascade of each of the frames.

A blast of 0.2 cubic metres of air at 1 mPa delivered through a single lance has a remarkable effect upon the earth. In essence it inflates it and the surface of the earth can be seen to rise even with a single lance delivering air at a depth of several metres. The initial blast has considerable force and will usually clear any obstructions in the lances or any material which may have built up since last use it will also crack the subsoil. This is hereinafter termed soils fracturing and the effect is to open up the subsoil into smaller subsections with perhaps 300 mm or so between fractures dependant upon the soil in question.

With the soils porosity increased (generally by the creation of preferential pathways) attention can be paid to driving out more groundwater and with it some of the dissolved contaminant or contaminant in suspension. It can also dislodge caches of such contaminants.

Pressure is now applied to the upper inner frame 147 with suction either continuously applied to all other frames or cascaded to all other lances 20 frame by frame 147 148. This may be done simultaneously or sequentially but if sequentially then reasonable rapidly to avoid spreading the plume of contamination under the effects of the central high pressure air..

The combined effect of central pressure with peripheral suction is to drive moisture out of the treatment block 21 to the peripheral suction points or to the central bore 146 where suction can also be applied by virtue of the suction port 79. This will continue for a time specified by the protocol which time will have been defined by site test of the average time taken to complete the clearance of a treatment block of that size on that site.

With the groundwater removed compressed air may be infused again high pressure in the upper centre frame 147 upper or stage 1, is countcrbalanced by suction applied to all other frames. In this way the infused air can be recovered together with any soil gases (including those produced by volatilisation of the contaminant). Where the suction pump has insufficient capacity then air may be drawn of using a known compressed air venturi pumping system attached to the same lances 20 through the SBS Unit 22. The gases so recovered may be collected or flared off from a point 250 to achieve satisfactory discharge or recovery as approved by the regulatory authority.This is shown in fig 12 Once the contaminant is reduced such that the volatile fractions are recovered then a full positive air pressure regime may be introduced by varying the protocol and changing the computer programme which is written to an EPROM ready for use by exchange to the base unit of the Programmable Logical Controller 103. Now air can be infused evenly from each lance 20 if desired.

With air flowing through these fractures or preferential channels (at approximately the same pressure as is measured as back pressure in the system in operation) a steady stream of air is brought to bear upon subterranean material which has not generally received such aeration.

This aeration serves now to create conditions where the subsoil becomes an aerobic rather than anaerobic domain. Such aeration now continues for a specified period.

With the aeration time complete the nutrient injection cycle commences and nutrient fluid carefully prepared to be sufficiently dilute and containing all required nutrient and hopefully a population of micro-organisms. This can be injected on a lance by lance and frame by frame basis with suction forces being used to assist positive air pressure. Later on during the treatment conditions will change yet again and it is then possible to proceed utilising air pressure alone,injecting fluid through all lances at once since risk of such action causing a spread of the plume will have abated as all the free phase contaminants have by that time been recovered.

After each nutrient charge is applied to a lance an amount of compressed air is sent through the distribution system behind it to obtain the best possible dispersal.

With the nutrient dose fully delivered a final cascade of individual air blasts to all frames clears all lances and lines before a beacon or horn sound to indicate completion. Now the SBS Unit 22 may be moved or connected to the next treatment block and the process restarted.

Such a labour intensive phase as is described above will last for a finite length of time.

Ultimately it is possible to couple more and more lances such that frames are treated collectively and then only one port of an SBS Unit 22 needs to be devoted to one frame 146,147. In such a case an SBS Unit could serve 8 treatment blocks at a time in each 'pass'. In a further development only two ports and then only one port will be required per treatment block 21 such that ultimately in the later stages of treatment and SBS Unit would be capable of serving 32 treatment blocks simultaneously. The length of time taken to arrive at this scenario is a site specific issue.

Ultimately the contamination will be reduced by the combined effects of all migratory pathways sufficient for the site to be audited by a final bio-assay from which it is hopefully possible to certify that the site has been cleaned to a background level of contamination approved by the regulatory authority.

Claims

Claims relating to the SBS Close Lance Svstem

1. An soils decontamination system comprising a number of soil penetrating lances connected by a piped network to external sources supplying fluids and motive forces.

Related Issue - Main system

2. A soils decontamination system as claimed in Claim 1 wherein the soil penetrating lances are installed in the soil in an array with the same or similar spacing between lance centres.

Related Issue - Lance spacin

3. A soils decontamination system as claimed in Claim 1 or Claim 2 wherein a number of soil penetrating lances each lance having a number of independent outlet regions is installed in the soil spaced between pairs of outlet regions such that the effective treatment volumes defined around each such outlet region overlap.

Related Issue - overlap

4. A soils decontamination system as claimed in Claim 1 or Claim 2 or Claim 3 wherein the soil penetrating lances are individually connected to a variety of external sources of fluids or motive forces by means of a piped network controlled by a system of valves operated by computer control .

Related Issue - valve control

5. A soils decontamination system as claimed in Claim 1 or Claim 2 or Claim 3 wherein all of the lance outlet regions are each connected to the piped network in a manner which permits the supply of any fluid to any lance outlet region independantly of any other lance outlet region.

Related issue - Systematic connection

6. A soils decontamination system as claimed in Claim 1 or Claim 2 or Claim 3 wherein the supply of fluids from external sources may be supplied simultaneously to a group of lance outlets regions being a proportion of the lances in the array of lances independently of any supply of fluids to any other grip of lance outlets regions.

Related Issue - Sub-group supply Claims relating to external connections to tlance design

7. A soils decontamination system as claimed in Claim 1 or Claim 2 or Claim 3 wherein a lance consists of a single tube, extendable by the introduction in short lengths of similar tube with a smooth means of connection between the sections each lance having an outlet region towards one end of the lance and a connection to an airline at the other.

Related Issue - Single lance

8. A soils decontamination system as claimed in Claim 1 or Claim 2 or Claim 3 and wherein a lance consists of a multiple tubes extendable by the introduction in short lengths of similar tube with a means of connection between the sections each lance each such tube having an outlet region towards one end of the lance and a connection to an airline at the other independant of any other tube within the lance..

Related Issue - multiple lanc

9. A soils decontamination system as claimed in Claim 1 or Claim 2 or Claim 3 Or claim 7 or claim 8 wherein the outlet regions to each lance consists of at least one oultet drilled radially to the long axis of the tube forming the lance.

Related Issue - radial outlets

10. A soils decontamination system as claimed in Claim 1 or Claim 2 or Claim 3 or claim 7 wherein one end of the lance, being the end inserted to the soil, is formed with an orifice smaller than the internal diameter of the tube forming the lance, which orifice remains open during installation accomplished by the ejection of high pressure gas through the orifice and is closed by a spherical object blown down the tube forming the lance when the lance is installed to its desired position.

Related Issue - boring tip Claims relating to the SBS Unit

11. A soils decontamination system as claimed in Claim 1 or Claim 2 or Claim 3 wherein the valves controlling the piped network are all contained within an independent casing.

Related Issue - SSBS Unit a valves

12. A soils decontamination system as claimed in Claim 11 wherein there is connected a suitable computer system dedicated to the management and control of the vales controlling the piped network.

Related Issue - Computer

13. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon a means of connection to each lance outlet region.

Related Issue - connect lanc

14. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon a means to each source of fluid supply or motive power.

Related Issue - supply ports

15. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon there are facilities for connecting the pipe network to an external supply of compressed gas.

Related Issue - connection compressed 7. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon there are facilities for connecting the drain of the internal pipe network to an external suction pump.

Related Issue - pipe connection pump 8. A soils decontamination system as claimed in Claim 11 or claim 12whereon there is an external connection for a pipe to extend suction to a borehole within a treatment block.

Related Issue - Pumping b suction connection Claims relating to controls upon the SBS Unit 10. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon there is a start button for physical engagement and commencement of the computer system.

Related Issue - Start button 11. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon there is an emergency stop button for physical disengagement of the external electrical supply from the internal electrical connections.

Related Issue - Emergency stop 12. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon inclusive whereon there are facilities for Related Issue - Bypass 13. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon there are facilities for sensing the pressure of the air controling the operation of the valves controling the piped network.

Related Issue - Control press 14. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon there are facilities for Related Issue - Spring air pr 15. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon there are facilities for automatically counting events within the operation of the system bya counter incremented by the computer.

Related Issue - Counters

16. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon whereon there is a means, operated by a computer, of indicating, by sound or visual signal to indicate a particular event within a computer programme.

Related Issue - Beacon or ho Claims relating to electrical systems within the SBS Unit

17. A soils decontamination system as claimed in Claim 11 or Claim 12 whereon there is an industry standard facilities connection for an external electrical power supply 130.

Related Issue - connection power

18. A soils decontamination system as claimed in Claim 11 or Claim 12 wherein there is a transformer for reducing the voltage within the casing to 24 volts for internal purposes.

Related Issue - 110v -2 trans

19. A soils decontamination system as claimed in Claim 11 or Claim 12 wherein there are are facilities for connecting the internal electrical supply within the SBS unit to the external suction pump through a relay activated by the computer at the time called for in the active computter programme.

Related Issue - electrical control of suction pum Claims relating to the SBS distibution valving systems

20. A soils decontamination system as claimed in Claim 11 or Claim 12 wherein a plurality of piped cross connections between the distribution pipes arranged into separate cross connections to match the number of sub-groups determined in each array of soil penetrating lances.

Related Issue - SBS U Cross connection and frames the lance arr

21. A soils decontamination system as claimed in Claim 11 or Claim 12 or Claim 20 wherein a piped network with each such cross connection having a valve to control input to the lance connection ports spaced along the length of the cross connection together with a number of pneumatically powered valves controlling outputs to or inputs from each individual lance.

Related Issue - SBS UNIT Model 1 w stack p system

22. A soils decontamination system as claimed in Claim 20 consisting of a network of pipes branched from main distribution pipes via a system of plenum chambers with outlets to the supply of fluids and motive forces and outlets to the lance outlet refgions, each such plenum chamber having at its centre a substantial disc with a number of sealing members thereon each such sealing member arranged in a ring upon the disc which is also a rotatable plate which can also be moved in a lateral direction normal to the plane of rotation all manipulated by stepper motors and eletro magnets themselves under the control of the computer.

Related Issue - SBS UNIT Model 2 w discvalve a plenum syste Claims relating to the reservoir svstem

23. A soils decontamination system as claimed in Claim 11 or Claim 12 or Claim 20 within which a vessel of fixed known volume into which fluid resources may be drawn and from which they may be under the influence of a high pressure gas.

Related Issue - Chamber 77

24. A soils decontamination system as claimed in Claim 23 within which a system of valves manipulatted under computer control and capable of moving g the inducted fluids and resources within the piped network under the influence of suction or negative pressure.

Related Issue - Lances un suction Claims relating to lances and arrays

25. A soils decontamination system as claimed in Claim 6 wherein lances with independent regions of discharge at differing depths but similar surface position.

Related Issue - discharging different dep

26. A soils decontamination system as claimed in Claim 6 and wherein lances each having at least one horizontally oriented outlet region directed radially from the centre of the lance.

Related Issue - radial outlet lances

27. A soils decontamination system as claimed in Claim 6 wherein lances each having a plurality of independent outlet regions with each region having at least one horizontally oriented outlet regions directed radially form the centre of the lance.

Related Issue - multiple outl Claims relating to oPeration of the svstem under computer control

28. A soils decontamination system as claimed in Claim 6 wherein means of recovering pollutants and groundwater and other fluids from the soil by means of suction through the network and lances.

Related Issue - direct recov of polluta and pollu groundwat er

29. A soils decontamination system as claimed in Claim 6 wherein means of utilising compressed gas to break up dense soils to permit treatment to proceed.

Related Issue - compressed used to br up soils

30. A soils decontamination system as claimed in Claim 6 wherein means of distributing chemicals in a carrier fluid throughout the effective treatment volumes of soil by use of compressed gas (including air).

Related Issue - chemical

31. A soils decontamination system as claimed in Claim 6 wherein means of distributing nutrients in a carrier fluid throughout the effective treatment volumes of soil by use of compressed gas (including air).

Related Issue - nutrient

32. A soils decontamination system as claimed in Claim 6 wherein means of distributing oxygen throughout the effective treatment volumes of soil by use of compressed gas (including air).

Related Issue - oxygen 32. A soils decontamination system as claimed in Claim 6 wherein means of distributing micro-organisms in a carrier fluid, throughout the effective treatment volumes of soil by use of compressed gas (including air) Related Issue - augment

33. A soils decontamination system as claimed in Claim 6 wherein means of distributing suction throughout the effective treatment volumes of soil by the use and control of an external suction pump.

Related Issue - suction

34. A soils decontamination system as claimed in Claim 6 wherein means of and claim 28 and claim 29 and claim 30 and claim 31 and claim 32 an/or any combination of Claims 1 or claim 6 or claim 20 and claim 28 and claim 29 and claim 30 and claim 31 and claim 32 a co-ordinated quantified and time manner.

Related Issue - combination resources Claims relating to explouitation of multiple migratory pathways

35. A soils decontamination system as claimed in Claim 6 wherein means capable of utilising any or all of the migratory pathways (direct pumping, leaching, solubilisation, volatilisation bio-remediation) singly or in any combination by virtue of setting and re-setting the valves of the network.

Related Issue - Combination migratory pathways

36. A soils decontamination system as claimed in Claim 6 wherein valves positions set and subsequently revised to utilise more than one migratory pathway either simultaneously or sequentially.

Related Issue - Similtaneous sequential of multi pathways

37. A soils decontamination system substantially as described herein with reference to figures 1-4 5A-5D, 6A-6D and 7-12 of the accompanying drawings and any other like device.

Amendments to the claims have been filed as follows 1 A device (22) having the purpose and capability of selectively controlling the distribution of multiple fluid resources, through a piped network to a system of soil penetrating lances that has been separately contrived for the in situ treatment of soil 2 A device as Claim 1 capable of concurrent connection to a variety of external sources of fluid resources (23,24,25,26), and the distribution of those fluid resources (23,24,25,26), by means of an internal piped distribution network (80,81,85,86) connected by pipes externally (28) to an array (21) of soil penetrating lances (20) contrived for the in situ decontamination of soil 3 A device as Claim 1-2 containing a multiplicity of valves (87,88,90) connected within the internal piped network (80,81,84,85,86) 4 A device as Claim 1 or Claim 2 or Claim 3 or any combination of Claims 1-3 inclusive, containing a programmable computer (66) 5 A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or any combination of Claims 1-4 inclusive, containing a plurality of valves (87,88,90) connected by electro-pneumatic or any other means to the computer 66 in a manner enabling control of the internal piped network (80,88,90) by the computer 66 6 .A device as Claim 1-4 wherein the valves (87,88,90) controlling the internal network (80,81,84,85,86) are manipulated by the programme running within the computer (66) 7 A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 having the capability of selectively inducting and / or distributing fluid resources through the internal piped network (80,81,84,85,86) 8 A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or Claim 7 having the capability of selectively controlling the movement of fluid resources propelled through the internal piped network (80,81,84,85,86) by means of a compressed gas.

9 A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or Claim 7 having the capability of selectively controlling the movement of fluid resources propelled through the piped network (80,81,84,85,86)) by means of suction obtained from an external source 10 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or Claim 7 or Claim 8 or Claim 9, wherein each alternate pathway through an internal piped network (80,81,84,85,86) may be subjected to an increase in ambient pressure, by the diversion of an external source of compressed gas delivering a pressure greater than 1 atmosphere, connected to the device (22) 11 .A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or Claim 7 or Claim 8 or Claim 9, wherein each alternate pathway through an internal piped network (80,81,84,85,86) may be subjected to an decrease in ambient pressure, by the diversion of an extemal source of suction delivering a pressure of less than 1 atmosphere, connected to the device (22) 12 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 having the capability of selectively inducting fluid resources through the piped network (80,81,84,85,86) by means of selecting alternate pathways of reduced ambient pressure.

13 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, having the capability of selectively moving fluid resources through the piped network (80,81,84,85,86) by means of selecting alternate pathways of increased ambient pressure.

14 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, having the capability of selectively inducting and / or distributing fluid resources through the internal piped network (80,81,84,85,86), in measured quantities..

15 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, having the capability of selectively inducting measured quantities of fluid resources through the piped network (80,81,84,85,86), such quantities being measured by timers within the computer programme 16 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, having the capability of selectively inducting and / or distributing fluid resources through the internal piped network (80,81,84,85,86) in measured quantities..

17 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 whereon there are facilities for connecting the lance ports (84) of the network to hoses or pipes (28) serving an array of soil penetrating lances (21) 18 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 whereon there are facilities for connecting the internal pipe network (80,81,82,83,84,85,86) to an external supply of a fluid. (25) 19 .A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, whereon there are facilities for connecting the internal pipe network (80,81,82,83,84,85,86) to an external supply of compressed gas (23) 20 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, whereon there are facilities for connecting the drain of the internal pipe network (80,81,82,83,84,85,86) to an external source of suction or pressure reduced below 1 atmosphere(24).

21 A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, whereon there is a start button for physical engagement and commencement of the computer system.

22 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, whereon there is a stop button for physical disengagement of the external electrical supply from the internal electrical connections.

23 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, whereon there is a facility for the connection of an external electrical power supply 130.

24 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, wherein there is a transformer for reducing the voltage within the SBS unit to 24 volts for all internal purposes 25 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 whereon there are facilities for connecting the internal electrical supply within the device (22) to the external suction resource through an internal relay activated by the computer (66).

26 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, wherein is contained a piped network (80,81,82,83,84,85,86) having main distribution pipes 85 (for fluids) and 86 (for suction) and 80,81,82,83 for the induction and diversion of resources with input connections for each, external any casing 84 27 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, having a plurality of piped cross connections 80,81,82,83, between the distribution stacks 85 and 86 arranged into separate cross connections to match the number of frames in each treatment block defined within the array 21 of soil penetrating lances 20; 28 .A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, containing a piped network (80,81,82,83,84,85,86) with each such cross connection 80,81,82,83 having a valve 87,88 to control input to the lance connection pipes 84 spaced along the length of the cross connections 80,81,82,83, together with a number of pneumatically powered valves 90 controlling outputs to or inputs from each individual lance.

29 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, consisting of a network of pipes XX branched from main distribution stacks 85 and 86 via a system of four plenum chambers each with a "Disc valve" system (150) powered by stepper motors and electro magnets.

30 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable, by means of the manipulation of the valves (90, 87,88) or discvalve 150 controlling the internal piped network (80,81,82,83,84,85,86), of the simultaneous diversion of increased and / or reduced ambient pressures, within individual and separated pathways within the internal network (80,81,82,83,84,85,86) each pathway independently connected to selected groupings of soil penetrating lances 20 by means of hoses 28 31 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of directly recovering pollutants and groundwater and other fluids from the soil by means of suction through the network (80,81,82,83,84,85,86) and soil penetrating lances. 20 and hoses 28 32 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of diverting high pressure compressed gas at more than 0.75 MPa via a piped network (80,81,82,83,84,85,86) to soil penetrating lances 21 in order to physically break up dense soils to permit in situ bio-remediation to proceed.

33 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of diverting and distributing chemicals in a carrier fluid throughout the piped network to soil penetrating lances by the diversion and release of a compressed gas (including air) through selected pathways within the internal piped network (80,81,82,83,84,85,86).

34 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of diverting and distributing nutrients in a carrier fluid throughout the piped network to soil penetrating lances by the diversion and release of a compressed gas (including air) through selected pathways within the internal piped network (80,81,82,83,84,85,86) 35 .A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of diverting and distributing oxygen in a carrier fluid via the piped network 80 to soil penetrating lances, by the diversion and release of compressed air through selected pathways within the internal piped network (80,81,82,83,84,85,86) 36 .A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of diverting and distributing nutrients in a carrier fluid via the piped network to soil penetrating lances, by the diversion and release of a compressed gas (including air) through selected pathways within the internal piped network (80,81,82,83,84,85,86) 37 .A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of diverting and distributing micro-organisms in a carrier fluid via the piped network to soil penetrating lances, by the diversion and release of a compressed gas (including air) through selected pathways within the internal piped network (80,81,82,83,84,85,86) 38 .A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of diverting and distributing suction in the form of air at less than a pressure of 1 atmosphere a piped network from soil penetrating lances, by the diversion and release of an externally supplied suction capability through selected pathways within the internal piped network (80,81,82,83,84,85,86) 39 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of the distribution of fluid resources in a simultaneous, co-ordinated quantified and timed manner.

40 A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of utilising all OR any migratory pathways (direct pumping, leaching, solubilisation, volatilisation or bio-remediation) singly or in any combination by virtue of setting and re setting the valves 90, 87,88, within the internal network (80,81,82,83,84,85,86).

41 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, capable of sequentially opening and closing valves 90,87,88 set so as to utilise more than one migratory pathway (direct pumping, leaching, solubilisation, volatilisation bio-remediation) either simultaneously or sequentially.

42 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, utilising pneumatically operated valves 90, 93 to control the network (80,81,82,83,84,85,86) 43 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, utilising a disc-valve and plenum chamber system. (150) 44 . A device as Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6 or claim 7 or Claim 8 or Claim 9 or Claim 10 or Claim 11 and/or any combination of Claims 1 - 11 inclusive, utilising a reservoir (77) or reservoirs for the containment and measurement of fluid resources prior to distribution to soil penetrating lances 20 45 A device as Claims 1 to Claim 45 inclusive and/or any combination of Claims 1 - 45 inclusive, or any other like device.