[Nitrogen compounds in the well water of Sokołów Podlaski district].

In the year 2002 the quality of well waters was monitored in the area of Sokołów Podlaski district. Water samples collected four times per year from twenty once dug and drilled wells were examined for : NO3-, NO2-, NH4+, PO4(3-), Cl-, pH, total hardness and electrolytic conductivity. These studies showed that 58% out of all the analyzed water wells did not meet the requirements of standards related to nitrogen compounds content. During the whole period of the studies only 2 wells among 21 investigated met all the required standards as far as the examined parameters. These were the drilled wells of relevant localization and well enough isolated from all the sources of pollution.