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A large class of explicit hyperbolic monopole solutions can be obtained from JNR instanton data, if the curvature of hyperbolic space is suitably tuned. Here we provide explicit formulae for both the monopole spectral curve and its rational map in terms of JNR data. Examples with platonic symmetry are presented, together with some one-parameter families with cyclic and dihedral symmetries. These families include hyperbolic analogues of geodesics that describe symmetric monopole scatterings in Euclidean space and we illustrate the results with energy density isosurfaces. There is a metric on the moduli space of hyperbolic monopoles, defined using the abelian connection on the boundary of hyperbolic space, and we provide a simple integral formula for this metric on the space of JNR data.

Thames Water operates about 400 sewage works in the catchment area of the River Thames, over half of these serve populations of less than 2000. These small works are mainly biological filter works but also include oxidation ditches and reed beds. Most of these works discharge to the headwaters of salmonid rivers which are used as drinking water sources and therefore have to meet high standards including in many cases full nitrification and low suspended solids. The paper describes the consent standards set for the works. Currently a number of small works do not meet these standards so Thames Water has committed itself to having all works operating within standards by 1992. There are a number of reasons for failure which include, overloading due to increase in population and water use, trade effluent discharges, and operational problems. Small works may also fail to meet their standards because they are unmanned apart from infrequent maintenance visits, and thus any plant failure may go unnoticed for some days. Thames Water is adopting a two fold strategy to overcome these problems. Firstly, so that operational problems may be identified quickly a simple cost effective system of automation and telemetry is being installed and secondly, to overcome operational and facility deficiencies, a Project Management team has been set up to identify the causes of failure, to prioritise remedial work, to recommend alternative operational strategies, if appropriate, to design and build extensions or new works if appropriate, and, if remedial works cannot be built quickly enough, to install temporary plant to ensure compliance with effluent standards.

Technical control of sewage sludge disposal to sea is carried out primarily to maintain the quality of the receiving environment and this paper discusses the control in the context of England and Wales. Control is exercised in several ways and by several bodies. There are international conventions and national legislation governing sludge dumping, the national legislation is enforced by the Ministry of Agriculture Fisheries and Food, who stipulate the required quality and quantity of sludge. The sludge is produced and disposed of by regional water authorities who must control the quality of their sludge and use trade effluent legislation to control effluent from industry. In turn industrialists must control their effluents to meet water authority standards and this usually requires the installation of water treatment equipment or even change of process. At all stages scientific methods are used to check the effect of the legislative control. It is important that the technical controls used to protect the environment are not over-stringent so that an economic and practicable method of sludge control is not wasted.