Brine Pumping Research Articles

Salt Mining and Associated Subsidence in Mid-Cheshire, England, and its Influence on Planning

Rock salt occurs in the Lower and Upper Keuper Saliferous Beds in Cheshire, the former being 190 m while the latter is 404 m in maximum thickness. Although most of the Triassic rocks in Cheshire are covered by thick superficial deposits, natural brine runs occur at the surface and salt was recovered from these springs as long ago as Roman times. Indeed, most salt was obtained in this way until the end of the seventeenth century. In 1670 salt was discovered at Marbury near Northwich, and the first mine was sunk in 1682. In the succeeding eighteenth and nineteenth centuries, the salt industry expanded enormously and many mines and brine pits were sunk. The mines frequently had a short life and poor mining practices often led to roof collapse and ingress of water. When water entered into a collapsed mine it attacked the pillars and walls and thereby penetrated into adjacent mines. As adjacent mines collapsed subsidence spread until sets of flooded mines formed large underground reservoirs. Associated “rock pit holes” occurred at the surface. In terms of salt production, wild brine pumping became increasingly more important and overtook mining in the nineteenth century. The most successful wild brine pumping occurred on the major pre-existing natural brine runs. Such abstraction accelerated the formation of solution channels and active subsidence was concentrated at the heads and sides of brine runs. Serious subsidences could occur at considerable distances from the point of abstraction (up to 8 km). Flashes, that is, water-filled linear hollows, are probably the most notable features produced by such subsidence. The most disastrous subsidences took place in the second half of the nineteenth century and were due to the development of bastard brine pumping, that is, pumping from abandoned mine workings. These subsidences occurred suddenly and were on a large scale, producing dramatic loss of property and even life. Bastard brine pumping also disturbed brine levels significantly which, in turn, gave rise to sudden local collapses. Because of the unpredictable nature of subsidence due to wild brine pumping, responsibility could not be attributed to any particular wild brine operator. Hence, two Compensation for Subsidence Acts (1891 and 1952) were passed which imposed levies on the operators in order to provide compensation funds for subsidence damage. The latter act primarily extended the compensation district. The number of wild brine pumpers declined throughout the twentieth century, and after 1968 the County Council withheld permission to extend pumping outside the demarcated areas and no permission was given to sink new wild brine wells. It was their intention to phase out wild brine pumping by the 19809s. This has very nearly been accomplished, controlled solution mining now producing 99 percent of the brine in Cheshire. It is alleged that this method of production has given rise to no subsidence.

The Opencast Coal Act 1958: the transition from wartime emergency powers to planning for amenity

The Opencast Coal Act of 1958 features large in every account of the fifty-year history of opencast coal working in the United Kingdom. It marked a crucial stage in the transition from a highly-centralised approach to planning the location, working and restoration of opencast coal sites towards a system that gave greater prominence to the local planning authorities. The three attempts made by government to secure legislation in the 1950s illustrate with particular clarity the political dimensions of deciding how much importance should be attached to property rights and amenity considerations at a time of pressing industrial and energy needs. While statutory land-use planning was first used to protect the environment from the damaging side-effects of mineral development in the inter-war period, it was not until after the Second World War that a closely-defined framework of control began to emerge. In the United Kingdom, a relatively sophisticated approach was set out in the Town and Country Planning Act 1947.1 Additional powers were, however, needed to tackle the special problems raised by individual industries. The Mineral Workings Act 1951 established an Ironstone Restoration Fund to assist in financing the reclamation of opencast workings in the East Midlands ironstone field.2 The Cheshire Brine Pumping (Compensation for Subsidence) Act 1952 introduced a basically similar procedure in the form of a levy on producers of white salt. There were Coal Mining (Subsidence) Acts in 1950 and 1957. Exceptional powers were also required to protect localities and persons from another, and completely new, form of mineral development, namely opencast coal-working. Although the reconciliation of economic and amenity interests in mineral working was an obvious matter for planning authorities, Cullingworth has stressed how it would be far too simplistic to portray planning as a continual battle for the preservation of amenity. In his words, planning was concerned with competing pressures on land and the resolution of those conflicting demands.3 So pressing was the need for adequate coal supplies at economic cost, during and after the war, that government itself acted as planning authority in determining the location and

Anatomy of a Modern Marine Sabkha in a Rift Valley Setting, Northwest Gulf of California, Baja California, Mexico: ABSTRACT

An extensive sabkha, 100 by 20 km (62 by 12 mi), caps Holocene siliciclastic tidal flats along the coast of Baja California in the northwest Gulf of California structural trough. This sabkha, bounded on the west by alluvial fans, is a complex of sand flat, saline mud flat, gypsum-halite pan, and supratidal mud flat subenvironments. The sand flat, transitional between the fans and the sabkha, consists of horizontally to wavy laminated sand washed onto the flats by sheetfloods from the fans under upper-flow-regime conditions. The sand flat passes into saline mud flats characterized by massive mud crowded with discoidal gypsum crystals grown within the sediment, destroying the layering. This intrasediment growth of gypsum is driven by evaporative pumping of brine from a shal ow subsurface brine body. A gypsum pan occupies a wide, shallow depression within the saline mud flat. After storm flooding (either marine or meteoric) the pan becomes a temporary saline lake with an algal mat overgrowing a siliciclastic storm layer. Precipitation of gypsum needles from the open lake brine and bottom growth of gypsum prisms produce a gypsum layer that mimics the algal mat topography. Evaporation of the lake leads to (1) vadose diagenetic growth of gypsum that distorts and polygonally disrupts the gypsum layers (2) deposition of a surface halite layer in the center of the pan. These layered pan deposits are the evaporites of the sabkha. Seaward of the saline mud flats are supratidal mud flats underlain by millimeter-thick laminites with deep prism cracks, sheet cracks, an scattered gypsum discoid crystals. Pervasive mud cracking during long periods of nondeposition completely disrupts layering, creating a massive arid soil. A beach ridge separates this sabkha complex from the burrowed and ripple cross-laminated intertidal sediments. End_of_Article - Last_Page 460------------

Experience in commissioning large desalination plants in the Middle East

Aspects of the design and construction of three major seawater MSF installations, with some 14 evaporators each producing about 5 mgd (22,000 m 3/day) are briefly reviewed. Initial problems were encountered with brine weir design at high brine rates, and painting. Remedial action was successfully incorporated in later plants in spite of the short timescale available. Recirculating brine pump sizing criteria and the performance of the on-load tube cleaning systems, and an external deaerator, are discussed. After-condenser corrosion on air ejector systems is also reviewed. Some modifications to plant specifications are suggested in the light of experience gained with these units.

Depositional History of Paleocene--Lower Eocene Flagstaff Limestone and Coeval Rocks, Central Utah

The Flagstaff Limestone of Paleocene and early Eocene age, and coeval rocks of the North Horn and Colton Formations of central Utah, were deposited in the Lake Flagstaff lacustrine-alluvial complex. The Flagstaff lake basin formed in response to postorogenic deformation along the Sevier thrust belt and Laramide basement uplifts that blocked drainage. The Flagstaff Limestone of the Wasatch Plateau consists of three members; the lower member, designated Ferron Mountain, and the upper, the Musinia Peak, represent major high stands of the lake. They consist of mudstone, brecciated and massive carbonate rock with rootlets and pedogenic features, laminated and structureless limestone, fossiliferous limestone, and oncolitic and sandy limestone. During deposition of the Ferron Mo ntain Member, the eastern margin of the lake was vegetated, very shallow, and episodically exposed. In contrast, a relatively steep, high-energy shoreline along active structural elements bounded the west side of the lake. The middle member, designated Cove Mountain, consists of mud-cracked dolomicrite, mudstone, and bedded and nodular gypsum. These beds reflect repeated contractions and expansions of the lake across a broad carbonate mud flat. Freshwater limestones that were deposited during expansions of the lake probably were altered to dolomicrite during contractions by evaporative pumping of brine on mud flats.

Salt and subsidence in Cheshire, England

Rock salt occurs in the Keuper Marl Series of Cheshire. There are two saliferous beds, the lower being 190 m and the upper 404 m thick. However, most of the Triassic rocks in Cheshire are covered by thick superficial deposits. Nevertheless natural brine springs occur at the surface and salt has been evaporated from these springs since pre-Roman times. Subsidence occurs as a result of wild brine pumping. Gradual collapse takes place above the subterranean brine runs giving rise to cambered depressions at the surface, the flanks of which are often interrupted by tension scars. Flashes occupy many of these depressions. The most disastrous subsidences occurred towards the end of the nineteenth century due to bastard brine pumping, that is, pumping, with reckless abandon, from old mine workings. The associated subsidences were rapid and caused the destruction of many buildings. One of the awkward characteristics of subsidence in salt due to wild brine pumping is that it is unpredictable, indeed subsidence may occur several kilometres from the point of extraction. This means that an individual brine pumper could not and still cannot be proved responsible for subsidence. Accordingly, the Cheshire Brine Subsidence Compensation Board was established by act of Parliament at the end of the nineteenth century which obliged each brine pumper to contribute towards the compensation fund. Because controlled solution mining has not given rise to subsidence in its 40 years of operation this form of extraction is eventually to be extended throughout the whole of the salt field, another field is now being developed. It is hoped to phase out wild brine pumping by the 1980's.

Some Problems of Subsidence and Land Use in the Mid-Cheshire Industrial Area

Industrial devastation is a major problem of all mining areas which undoubtedly warrants the incre sing attention being paid to it by geographers.1 A geographical approach to the study of derelict land, subsidence, and the disposal of industrial waste is valuable in providing data on the evolution of industrial landscapes and, more important, forms a basis for planned reclamation and restoration. In a paper previously published in the Journal% the unique subsidence phenomena of the mid-Cheshire saltfield were dicussed mainly from the standpoint of morphology and historical evolution. This short paper forms a sequel in which it is intended to amplify some of the points then raised, but not fully explored, relating to the effects of subsidence on human activities; in particular it draws attention to some new features of the land use problems of the saltfield which it was not permissible to publish when the original paper was prepared in 1954. Subsidence in its more violent forms is now rarely experienced in mid-Cheshire; the cataclysmic upheavals of the late nineteenth and early twentieth centuries have given way to a more insidious form of subsidence which works stealthily to the same end?dereliction. The change is to be explained largely by the adoption of different techniques of salt working, and by shifts in the location of salt manufacture. An important result of this latter change has been the appearance of subsidence in new areas within the saltfield, mainly near Sandbach. Subsidence was first experienced in this area during the eighteen-nineties, and was probably caused by the pumping of brine at the Wheelock salt and chemical works; it was then relatively insignificant in comparison with the great havoc wrought at Winsford and Northwich, the dominant centres of salt and chemical manufacture. However, after the First World War there were significant changes in the organization and distribution of the mid-Cheshire salt industry, which resulted in the virtual disappearance of salt manufacture from Northwich, the stagnation of the industry at Winsford, and its rapid expansion at Middlewich and Sandbach. 3 The consequent changes in the distribution and character of industrial dereliction can be seen from a comparison of the two maps (Fig. 1: a, b), which show the several elements of the industrial landscape in 1932 and 1957 respectively. The growth of the salt industry at Middlewich and Sandbach was accompanied by the formation of several large subsidence flashes within the area (Fig. 2a). Most of these were of the trough-like variety associated with natural brine pumping and, as they often lay in the valleys of rivers and small streams, the troughs were soon permanently flooded. It is unfortunate that the growth of salt manufacture in this part of the saltfield antedated the introduction of controlled brine pumping for, although most of the damage has occurred in unpopulated areas, this southward expansion of subsidence is a disturbing feature which shows little sign of abatement.4 Just as the expansion of salt manufacture at Middlewich and Sandbach has had unfortunate repercussions, so the almost complete decay of the salt industry at Winsford has appreciably reduced the incidence of subsidence. The great flashes to the south of the town have grown but little since the nineteen-thirties (Fig. 1: a, b) and have begun to silt up in part. In the Northwich area the introduction of controlled brine pumping by the chemical industry, the abandonment of the brine shafts which tapped the bastard reserves in the flooded rock-salt mines, and the contraction of the salt industry have combined to make subsidence much less virile than it formerly was. This does not mean to say that subsidence is no longer a problem over much of

British Food Journal Volume 51 Issue 10 1949

Although a comparatively rare disease in Great Britain, cases of trichinosis have been reported from different parts of the country from time to time. Statistics show that during the present century only 59 cases were reported prior to the Wolverhampton outbreak in 1941. Trichinosis is a parasitic disease. The Trichina spiralis lives in the small intestine, the female measuring about ⅛ in. in length and the male 1/16 in. The ova emerge as minute hair‐like embryos which burrow from the intestines to the musculature of the host. Thus if man consumes pork containing live trichinæ the larvæ are freed from their capsules by the action of the gastric juices, and maturity is attained in the small intestine. The female grows rapidly and at the end of a week gives rise to a swarm of a hundred or so embryos. The burrowing process starts again, and this boring into muscles produces intense muscular pains, swelling and tenderness, high fever, and other symptoms. The effects of cooking and preserving on infected meat are described by Mr. C. R. A. Martin, who says that thorough cooking for twenty minutes at a temperature above 150° F. is sufficient to destroy all trichinæ, providing the whole of the meat is subjected to this temperature for a similar period. It is obvious, therefore, that in domestic cookery boiling would be preferable to roasting in order to kill live parasites. Only very low temperatures (0°–5° F.) applied for three weeks have any effect on the vitality of trichinæ. Dry salting will kill all trichinæ in surface layers of the meat after exposure to the salt for fourteen days, but in the case of large bacon or hams a much longer exposure of eight to twelve weeks would be necessary, together with brine pumping of the thicker parts. Pickling in brine, if the brine is sufficiently strong, is a surer method of destroying larvæ. Smoking, partly through heat and partly the resinous products of burning pine sawdust, also has a slight effect on their vitality. It has, howver, been suggested that Memo. 62/Foods issued by the Ministry of Food, which recommends that a carcase affected with trichinosis should be condemned, is out of date and that there should be no grounds for ignoring the possibility of the disease during the ordinary routine meat inspections. In this connection, the recent circular dealing with outbreaks of cysticercus bovis infestation of cattle in different parts of the country should serve as a warning. A further warning is given in a letter to the British Medical Journal in which the writer deplores the way in which corned beef is served to the public. The procedure in the majority of shops, says the writer, is to open a large tin of corned beef and place the contents on a wooden cutting board. The same knife used for cutting uncooked sausages, uncooked beef, uncooked pork, and slabs of sausage meat is used, without any attempt at cleaning it, for cutting slices of corned beef. The writer goes on to say that the corned beef is then placed on the weighing machine plate, which quite normally in a butcher's shop is covered with blood. Further contact between the uncooked meat and corned beef is made when the wrapped (and sometimes unwrapped) corned beef is placed on top of the raw meat. Should parasitic worms or cysts which have evaded the eye of the meat inspector be present in the raw meat, they will be transferred to the corned beef by knives, by butchers' hands, by scales, and by direct contact with the raw meat. Many veterinarians have pressed for the detailed examination of pig carcases for trichinosis which would necessitate the removal of suspected muscle by means of a trichinoscope, but no such instrument is in existence in the abattoirs of this country. The whole operation, which is carried out as a matter of routine inspection in many Continental abattoirs, takes only a few minutes. Should simple safeguards in feeding and inspection be adopted, it seems fairly evident that the absence of a trichinoscope need not be regarded as a serious gap in our public health services, but the rarity of outbreaks of the disease in this country must not lead to complacency or to ignoring the possibility of its presence during the normal course of meat inspection.