Abstract—Several different cements have been tested to evaluate their potential to leach calcium, chromium and aluminum ions in soft water environment. The research allows comparing some different cements in order to the potential risk of water contamination. This can be done only in the same environment. To reach the results in reasonable short time intervals and to make heavy metals measurements with high accuracy, demineralized water was used. In this case the conditions of experiments are far away from the water supply practice, but short time experiments and measurably high concentrations of elements in the water solution are an important advantage. Moreover leaching mechanisms can be recognized, our experiments reported here refer to this kind of cements evaluation. Keywords—Concrete corrosion, hydrogen sulfide, odors, reinforced concrete sewers, sewerage. I. INTRODUCTION T is important to realize that many renovation methods successfully applied in sewerage are too expensive for water supply systems. This can be simply explained by deeper burial of sanitary sewers and by constructing them below roads while large diameter water mains usually go through green areas and small diameter water pipes go under pavements. Neither demolitions of road surface nor new organizations of road traffic are usually necessary for renovating of water mains. Because of this, only the cheapest methods of renovation are usually utilized for water pipes. The first method is cement mortar lining [1] and the second epoxy spray lining. These two methods are substantially different. Epoxy resin and polyurethane linings adhere strongly to the metal creating a mechanical barrier against diffusion of oxygen and ions. The mortar lining does not attach strongly to the pipe surface. This can be observed in Fig. 1. There is a thin layer of water between the lining and ductile iron. The pH of this water should be between 11 and 13, which is high enough to stop electrochemical corrosion processes. New ductile iron pipes are covered on the inside by cement mortal lining, except small diameter pipes produced for transporting soft waters with low alkalinity. In these unwanted circumstances mechanical protection is chosen. Recently mechanical protection by thin epoxy resin has become a more common choice for renovation of old cast iron pipes because the epoxy adhesive is thinner in comparison with conventional cement M. Zielina is with the Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland (corresponding author: +48 12 6282356; fax: +48 12 628 20 42.; e-mail: mziel@vistula.pk.edu.pl). W. Dabrowski and E. Radziszewska-Zielina are with the Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland (e-mail: wdabrow@pk.edu.pl, eradzisz@izwbit.pk.edu.pl). mortar lining without additives and does not require time for curing, tightening and surface smoothing. However, properly done cement mortar lining creates relatively low friction losses for water flow and its roughness does not increase rapidly resulting in stable or very slow deterioration of flow conditions during the time [2]. Some of the inconveniences of applying mortar lining are a high pH value and a raised concentration of calcium, aluminum and chromium [3], [4], usually in a short time after cast iron cementing or applying new ductile iron pipes, protected inside by cement mortar lining. In long periods of time, lining reduces number of complaints on the quality of drinking water. Fig. 1 A part of a cross section through a ductile iron pipe wall showing the bottom of cement mortar coating and the top of ductile iron cross section. A gap of a few micrometers is highly visible between the metal and the cement mortar lining II. PROPERTIES OF LINING Cement mortar lining produced in factory differs significantly from mortar lining done in the fields. In the first case, it does not matter whether centrifugal lining or spraying is applied. Fast rotation of the pipe sprays the mortar homogeneously and compacts it by the centrifugal force. In this case the inside surface of the mortar is smooth, the porosity of the whole layer is very small and the roughness of the internal surface is quite small. Sand grains are pressed by the centrifugal force towards the pipe’s internal wall surface while cement, in reaction with water, forms smooth surface of low permeability. Cementing of pipes in the field differs significantly from the two methods to be applied in the foundry. In the field after cleaning the pipe, the boom radial spray system is inserted and moves with a constant speed along the pipe ax. The head of Cement Mortar Lining as a Potential Source of Water Contamination M. Zielina, W. Dabrowski, E. Radziszewska-Zielina I World Academy of Science, Engineering and Technology International Journal of Environmental and Ecological Engineering Vol:8, No:10, 2014 723 International Scholarly and Scientific Research & Innovation 8(10) 2014 scholar.waset.org/1307-6892/9999592 International Science Index, Environmental and Ecological Engineering Vol:8, No:10, 2014 waset.org/Publication/9999592