In this paper, the pollutant removal efficiency and the reliability of a vertical and horizontal flow hybrid constructed wetland (CW) planted with common reed, manna grass, and Virginia mallow were analyzed. The wastewater treatment plant, located in south-eastern Poland, treated domestic sewage at an average flow rate of 2.5 m³/d. The tests were carried out during five years of its operation (2014–2018). The following parameters were measured: biochemical oxygen demand (BOD₅), chemical oxygen demand (COD), total suspended solids, total nitrogen, and total phosphorus. The results showed that more than 95% of BOD₅, COD, and total phosphorus was removed in the tested CW system. The average effectiveness of removal of total suspended solids and total nitrogen exceeded 86%. A reliability analysis performed using the Weibull probability model showed that the removal reliability in the tested CW was very high for BOD₅, COD, total suspended solids, and total phosphorus (100%). The probability that the total nitrogen concentration in the treated effluents would reach the limit value (30 mg/L) established for effluents discharged from a treatment plant of less than 2000 PE (population equivalent) to standing waters was 94%. The values of all the pollution indicators in wastewater discharged to the receiver were significantly lower than the limit values required in Poland. The investigated hybrid CW system with common reed, manna grass, and Virginia mallow guaranteed stable low values of BOD₅, COD, total suspended solids, and total phosphorus in the treated wastewater, which meant it was highly likely to be positively evaluated in case of an inspection.

The study investigated the efficiency of removal of iron, manganese and indicator bacteria from potable groundwater by using carbonate-silica rock (opoka). The tests were performed in a laboratory in three filter columns supplied with water containing increased concentrations of iron and manganese. Two of the columns were filled with carbonate-silica rock with particle sizes of 2-5 mm; retention time for water in the columns was set at 1 h and 2 h. A third column was filled with 1-2 mm rock particles, with hydraulic retention time set at 1 h. High removal efficiencies were determined for iron, manganese and coliform bacteria and low removal efficiencies for psychro- and mesophilic bacteria. An increase in the alkalinity of the investigated water was also observed.

The paper presents the results of research on the effects of removing pollution from domestic wastewater in two beds of constructed wetland systems with vertical flow. Bed I was planted with common reed ( Phragmites australis Cav. Trin. Ex Steud.), whereas bed II with Glyceria maxima ( Glyceria...

The work presented the assessment of household wastewater treatment plants with drainage systems on the quality of groundwater in dug wells and deep water wells in the area of 3 selected communes (Drelów, Dębowa Kłoda and Urszulin), located in the Lublin province in south-eastern Poland. The...

Hydropower plants in Poland currently use only 19% of the river’s energy potential. Development of hydropower is limited by environmental regulations as well as by economic grounds. From the environmental point of view, it is desirable to build small hydropower plants integrated into the local landscape. This paper presents results of the research aimed at estimating the amount of energy that could be produced in the case of small hydroelectric power plants on weirs existing on the Tyśmienica River. There is also a legal framework that should be adapted at hydropower development. It was calculated that the technical capacity of the small hydropower plants that could be built on 4 existing weirs, is 0.131 MW. These power plants could produce 786 MWh of electricity per year. The economic efficiency of this production is currently difficult to assess, because a new support system for renewable energy sources is currently being implemented, which will be a decisive factor for entrepreneurs. It should be borne in mind that potential investments will be made in protected areas within the Natura 2000 network, which may limit their constructing or impose the obligation to assess their impact on selected environmental elements. Location within the protective area does not eliminate such investments, especially when solutions with the least possible environmental impact are used.

Rational use of surface and underground waters leads to a reduction in their consumption, which is currently one of the fundamental tasks in the field of the conservation of waters, in its broad sense. This includes also the utilisation of water from additional sources, such as e.g. precipitation...