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Kitchen waste from vegan households can be a raw material for home or backyard composting. However, the use of waste without components like eggshells or meat can constitute several problems, including the decrease of the process temperature and the content of Ca, N, K, Mg, Mn, Na, and S. The scientific aim of the study was to investigate possibility of production and applicability of vegan compost (VC) produced from kitchen waste during 12-weeks backyard composting. The VC properties have been compared to the traditional compost (TC), made from plant- and animal-origin waste materials. Analyzes showed that VC and TC have similar properties, reaching a pH close to 7.5, respiratory activity AT4

The paper deals with the problem of wastewater treatment with specific physicochemical composition (increased ammonium nitrogen concentration) which were generated in Motor Rest Areas (MRA). Conventional biological wastewater treatment systems with activated sludge were used to purify the wastewater from sanitary equipment used in MRA. On the basis of the research conducted on four MRA, an attempt was made to determine the impact of the wastewater quality on biological wastewater treatment processes. The wastewater supplied to the treatment system was characterized by predominance of biologically non-degradable organic matter (average BOD/COD ratio 4.39 – 10.42) as well as high concentration of ammonium nitrogen 273.9 – 334.55 mgN-NH4/dm3. The wastewater alkalinity determined by high content of ammonium nitrogen had a negative impact on the biological treatment processes. Unequal pollution load and temporary, high hydraulic load caused leaching of solid suspension from settling tank as well as leaching of particles of activated sludge from the reactor’s chamber. The lack of organic matter susceptible to biological decomposition makes it difficult to develop the biocenosis of activated sludge, and the limits of ammonium nitrogen concentration inhibit the nitrification processes.

The rivers of agricultural catchment areas are particularly vulnerable to eutrophication, which causes nitrate nitrogen (N-NO3) that can be easily leached from the cropland. In 1991, the EU implemented the Nitrates Directive (ND) to identify and reduce the negative effects of nitrates in water. According to this regulation, in 2018, the whole territory of Poland was classified as Nitrate Vulnerable Zone (NVZ). The aim of the study was to assess the validity of the introduction of NVZs in large areas of the river catchment level. Statistical data on agricultural changes for individual provinces of Poland and for the whole country were analyzed. A one-way analysis of variance (ANOVA) was used to assess the N-NO3 content in the water at different locations along the river within four rivers in the Odra basin. The results indicated that higher concentrations are observed in the upper part of the studied catchments, which reached a maximum of 25.0 mg N-NO3·dm−3. However, average values rarely exceeded 11.3 mg N-NO3·dm−3, the limit according to the Nitrates Directive. The large variability in N-NO3 content suggests the need to redefine the actual NVZs since it is essential for the appropriate implementation of programs aimed at restoring water quality according to ND.

Wastewater treatment in semi-natural systems, such as a hydroponic lagoon operating as the third stage of purification, is becoming more and more popular because of the efficiency of nutrient removal. Very often treatment processes in hydroponic ditches are supported by algal growth, which can cause an increase in the concentration of total suspended solids in the outflow from the wastewater treatment plant. The aim of this study was to analyse changes in the granulometric composition of particles in the hydroponic lagoon operating as the third stage of wastewater purification in a municipal wastewater treatment plant (WWTP) in Poland. Measurements of the particle sizes were made with the use of the laser diffraction method. The results showed that the size of the particles in the hydroponic lagoon varied from 0.01 to 1000 μm. Analyses of the average diameters D(3.2) and D(4.3) showed that particles have low reactivity but good sedimentation properties and their fractal dimensions are usually higher than 2.0, which indicated that they had well-developed surfaces. Most of the particles flowing out of the WWTP were probably algae or particles that could adsorb other pollutants onto their surfaces. The use of laser granulometry for particle identification might be useful in characterizing the total suspended solids as well as helping to develop cheaper and more efficient methods for its removal.

The aim of this study was to analyse the impact of velocity in the hydroponic lagoon used as the 3rd stage of municipal wastewater treatment on washing out of the particles suspended in the sewage as well as settled on the bottom of the hydroponic ditch. In order to analyse the flow velocity in the lagoon, 12 cross-sections were determined at points where the speed and motion of particles can change. Wastewater samples were taken in the summer month from each of the 12 sampling points (the depth of 0.1 m) and the basic physicochemical parameters of sewage were determined (BOD5, COD, TOC, TSS, turbidity). In selected cross-sections, a granulometric analysis of particles was made to determine the characteristics of suspended solids in the wastewater flow path. Based on the analysis, it was found that velocities in the lagoon during aeration can be ten times higher (0.070 m·s−1) than those assumed by designers (0.006 m·s−1). Such a large difference means that the sedimentation conditions assumed in the project cannot be met, which may result in an increase in the total suspended solids and organic matter concentrations at the outflow to the receiving water body. During the flow through the hydroponic ditch, the highest efficiency of pollutant removal was indicated for BOD5 — 88.7% and TSS — 80%, while the COD removal occurred with the lowest efficiency — 34.1%. Improving flow conditions as designed in the hydroponic lagoon technological project may increase the efficiency of wastewater treatment at the third stage of treatment.

Effective removal of nitrogen and phosphorus from sewage before its discharge to the receiving water body is now a key task for scientists and technologists around the world. The widespread problem of eutrophication in the watercourses as well as in the seas and oceans obliges to take actions leading to more effective protection of water resources and implementation of sustainable development principles. One of the methods of increased wastewater treatment from nutrients is the use of a third stage of treatment with the use of macrophytes for the uptake of nitrogen and phosphorus. These systems, called hydroponic, under moderate climate conditions show little effectiveness due to the lack of sufficient light intensifying the growth of aquatic plants. The aim of this study was to evaluate the reduction of biogenic compounds concentrations in wastewater where additional lighting of plants was provided by the use of LED (Light Emitting Diodes), in two different conditions of experiment: with aeration and with carbon dioxide supplementation. Analyses show that the effectiveness of purification was higher in the wastewater supplemented with CO

The paper presents the results of research on the quantity and quality of wastewater in municipal wastewater treatment plant in Głogówek in period with and without rainfall. For runoff coefficients, amount of rainwater collected with combined sewerage system was evaluated as well as solutions which could limited the rainwater collected by canalization were proposed. Observations were carried out in the period 2015 – 2017. The amount of wastewater treated in wastewater treatment plant in Głogówek was 884,6 m3d-1 and the maximum value of inflowing wastewater accounted 84,5 % of the project value. The treatment efficiency in research period was high 96,8% for total suspension, 98% for BOD5 and 91,7% for COD respectively. During the observation period, the impact of increased inflow of rainwater on the outflow quality wasn’t observed. The reduction of pollution level in period with increased wastewater inflow was above 90%. The treatments that increased retention of the catchment allow to reduce inflow of rainwater by 41,3%.

The aim of research was to evaluate changes in the particle size distribution in two hydroponic lagoons working as a third stage of wastewater treatment where purification processes are based on plants and algae activity. Wastewater samples were taken during the winter and summer half of the year. In the samples taken from analyzed hydroponic lagoons the range of particles size was very wide (0.01 – 1000.0 μm). In both of the research facilities, the fractal dimension (Df) of particles was close to 2.0 what decides about developed surface of the particles. The results may indicate the predominance of algae cells in the total amount of suspensions. This information may pay a key role in determination the impact of discharged particles on the receiving water bodies quality as well as can be the main factor that allows to improve the system of suspended solids removal.

This paper focuses on the agronomic evaluation of a synthetic NPK (N in the form of urea, P and K in the form of phosphate monopotassium) fertilizers blended with four types of pine (Pinus sylvestris L.) wood biochar prepared at different thermal regimes (300 &deg, C, 400 &deg, C, 600 &deg, C and 700 &deg, C). The evaluation of benefits was done based on crop nutritional status and soil fertility. The pot experiment was set up with fertile Haplic Luvisol fertilized with 1.85 g kg&minus, 1 of blends of biochar (1.25 g) with urea (310 mg) and KH2PO4 (290 mg), which is equivalent to 500 kg ha&minus, 1 (biochar ~67.6%, N ~7.8%, P ~3.6%, K ~4.7%) applied before sowing. Only NPK blends made with biochar containing 75% or 85% carbon increased the biomass of 27-day old wheat seedlings from 12% to 20% in comparison to NPK applied alone. These blends raised the content of Mn and Fe in plants but decreased the contents of Ca and Mg. All the tested mixtures enhanced soil fertility by increasing the content of humic acids. Additionally, the content of potentially phytotoxic phenolic compounds was lower. In general, the addition of biochar to NPK fertilizer did not show a negative effect on crop quality. The overall results of the study suggest that the application of low doses of biochar to synthetic fertilizer can benefit crops and can support soil fertility.

W pracy przedstawiono prawne aspekty budowy przydomowych oczyszczalni ścieków przede wszystkim w świetle przepisów miejscowych planów zagospodarowania przestrzennego, jak również w kontekście procesu budowlanego. Autorzy szczególną uwagę poświęcają orzeczeniom sądów administracyjnych wydanych na skutek toczących się postępowań administracyjnych o wydanie pozwolenia na budowę, jak i postępowań administracyjnych toczących się po złożeniu przez organ administracyjny sprzeciwu od zgłoszenia budowy przydomowej oczyszczalni ścieków. Sądy administracyjne w ramach sprawowanej kontroli w tym zakresie oceniały również postanowienia miejscowych planów zagospodarowania przestrzennego w kontekście dopuszczalności budowy przydomowych oczyszczalni ścieków. Ewentualne ograniczenia budowy przydomowych oczyszczalni ścieków stanowią wyjątek od zasady nienaruszalności prawa własności właściciela nieruchomości i z tego powodu winny być w sposób szczególny uzasadnione. W takim przypadku względy ekonomiczne są w sposób oczywisty niewystarczające i tym samym każdy zakaz w tym zakresie winien być zgodny z konstytucyjna zasadą proporcjonalności.

A digital terrain model of the Strzelin granite quarry was created from ISOK project data obtained from airborne laser scanning (ALS). Based on 2009, 2012, and 2014 data, the volume of water in the Strzelin quarry’s two excavations were determined. Additionally, the predicted volume of retained water after mining ceases was calculated, assuming a water level of 150.0 m a.s.l. In 2014, the two reservoirs retained, respectively, ≈ 0.14 and 0.01 million m3 of water. If the two pits are eventually connected, ≈ 6.6 million m3 of water could be retained. Including the 2014 water volume as a small-scale retention basin would increase the volume of retained water in the Śleza catchment and Strzelin County by 19.0%, and 34.2%, respectively. The hypothetical reservoir created after mining ends would increase small-scale (reservoir and pond) retention ≈ 8 times in the Śleza catchment and ≈ 15 times in the County, constituting a significant improvement.

The paper presents the results of the research concerning the amount of wastewater influent to the wastewater treatment plant in Sława through sewerage system as well as the amount of wastewater delivered by the sanitation fleet. The research was conducted between January 2013 – Septemper 2017. In this period, the daily wastewater inflow to the wastewater treatment plant and monthly sums of wastewater delivered by the sanitation fleet were evaluated. The average volume of the treated sewage was compared to the designed value. The average measured wastewater inflow in the research period was 1971.1 m 3 ·d -1 and constituted about 66% of the designed inflow to the wastewater treatment plant. Additionally, the percentage share of wastewater delivered by sanitation fleet was estimated in comparison to total amount of treated wastewater. The seasonal changes concerning the quantity of wastewater delivered be the sanitation fleet, resulting from the touristic characteristic of region was taken into account. The seasonal variation had an influence on increasing the percentage of wastewater from septic tanks, cesspools compared to wastewater from sewerage system. In the summer months (July, August), in the analysed period, the percentage share was from 17.1% to 19.9%. Significantly, the shares of the delivered wastewater by sanitation fleet in the summer period, compared to wastewater amount from the sewerage system, could cause technological problems as well as influence the treatment efficiency.

This work presents the outcomes from two independent studies evaluating the chemical quality of groundwater in agricultural areas irrigated with wastewater from sugar and yeast industries. The evaluation was determined using chemical parameters representing typical contaminants of sugar industry wastewater (SIWW) and yeast industry wastewater (YIWW), and characterising the content of organic matter (BOD5), nutrients (NH4-N, NO3-N, TN and TP) and salts (Cl, SO4, Na and K). The studies reveal that food industry wastewater constitutes a valuable water-nutrient-rich medium that can be reused in agricultural applications as an alternative water resource for irrigation and nutrients for fertilisation. Furthermore, the reuse facilitates the sustainable discharge of wastewater through a soil-aquifer zone to the natural environment. This does not affect chemical quality of groundwater, which was comparable in areas irrigated and non-irrigated with SIWW and YIWW. Although some parameters (NO3-N, NH4-N, SO4, Cl and Na) displayed higher concentrations in groundwater from the fields irrigated with wastewater, these contents were within recommended health-based guideline limits defined in either the groundwater quality standards or the drinking water quality norms. Only the contents of K revealed an exclusive groundwater impact from wastewater irrigation. This was confirmed in statistical tests employing the Ward’s hierarchical clustering method, which exposed excessive amounts of K introduced into groundwater through irrigation with both SIWW and YIWW. However, this parameter is not considered to pose any health risk to humans or the environment, and its content is not restricted by quality guideline values for either groundwater or drinking water.

Treatment of wastewater produced in Service Areas (SA) located on expressways and highways is a worldwide problem because of increasing amount of roads and specific composition of those kinds of sewage. Insufficient removal of pollutants from wastewater discharged into surface water may cause serious environmental problems. In the present study efficiency of treatment of wastewater with high ammonium concentration in biological membrane system used on SA was investigated. Concentrations of ammonia nitrogen in wastewater flowing into bioreactor in none of the tested objects did not fall below 99.0 mg of N-NH4·dm−3. Because of high ammonium content in sewage and high pH reaching value about 9, it is almost impossible to create favorable conditions for microorganisms that run purification processes resulting in low efficiency of phosphorus and nitrogen removal (reduction of biogenic compounds did not exceed 15%). Treatment of wastewater consisting mainly of urine with commonly used biological membrane technology has to be widely tested to perform suitable quality of discharged wastewater, to provide safety of surface water environment.

The study presents the legal requirements concerning the quality of wastewater discharged to waterbodies and to soil after treatment in household wastewater treatment plants located in agglomerations or outside them. The procedure of stopping the operation of a household treatment plant that doesn’t meet the statutory wastewater treatment efficiency was presented. The decision ordering to stop the use of a household wastewater treatment plant has to be preceded by a decision ordering to take measures to limit its adverse impact on the environment. The clarification procedure has to determine the adverse impact on the environment in a doubtless manner and it has to be reflected in the documentation. The assessment of adverse impact should take into account the binding standards of use of the environment. Stopping the operation of a household wastewater treatment plant may result in issuing a decision ordering the user to connect to the sanitary sewage system.

The paper presents information related to the use of hydrophytic technology combined with traditional activated sludge solution for wastewater treatment in areas without central sewage system. The analyzed wastewater treatment plant (WWTP) was operated in activated sludge technology with hybrid activated sludge reactor where biomass is kept in settled and suspended form. Treatment system was completed with hydroponic lagoon. Hydroponic lagoon has been used as tertiary treatment, in which the self-cleaning processes with the participation of the plant has come to an additional reduction of nutrients. Analyzed three stage treatment plant is located in the municipality of Nowa Sól. Only domestic wastewater delivered by slurry tanks are treated there in amount of 60 m3/d. During the observation high average concentrations of total nitrogen (201.0 mgN/dm3) was observed and organic matter expressed by COD reaching 1341.5 mgO2/dm3 and BOD5 on the level of 246.3 mgO2/dm3 were noted. A characteristic feature of an object designed for wastewater treatment delivered by slurry tanks is high irregularity of wastewater supply and high instantaneous loads of pollutants (the system does not provide expansion tank). The biggest inequality factor of the flow to the reactor was observed in December 2014 (Nd=3.9). During the observations also occurred days with no inflow of sewage. The study shows the dynamics of changes in the amount of delivered domestic wastewater and sewage flowing out of treatment plant including inequality factor. Information about quality of wastewater was used to determine the reduction of concentrations of pollutants like organic matter, suspended solids, nitrogen and phosphorus.

In Poland about 40% of the population lives in a rural areas and despite of the great technical progress in the infrastructure, there are still areas without water supply system where portable water is drawn from the well. The subject of this work was to evaluate the quality of shallow well water (98–604 cm), which is a source of water for consumption. Studies covered 8 wells in the Gorzyce commune. The following chemical components: pH, dissolved oxygen, electrolytic conductivity, BOD5, nitrogen, total phosphorus and phosphates, and ions of SO4-, Na, K+, Ca++ and Mg++ were analyzed. The results of the studies are described by the mean concentrations of components in analyzed period of time. The results confirm the fact that, poorly protected wells have a worse quality of water. Moreover a few cases, the average concentration of the analyzed indexes exceed acceptable standards for drinking water.

Carbon dioxide sequestration and its long-term immobilisation in biomass is recently an extremely significant problem. Its greatest reserves occur in forests growing all over the globe. A human being, through their conscious action, ought to affect, among other things, the amount of carbon dioxide discharged into the atmosphere and its rational management. Here, quite a good solution seems to be the immobilisation of CO2in biomass of plants, and in particular, in trees, characterised by their longevity, which are used most frequently for that purpose.Such carbon dioxide management allows for its several-decade immobilisation within living plants, while a further processing of wood mass allows for halting it for consecutive years in products manufactured. Additionally, in the case when within a selected land planted with trees the effluent irrigation is being carried out, simultaneous sewage treatment is also an advantage. By using plants characterised by intense increment in biomass within facilities, also biogens occurring in effluents may be effectively removed.In the analysed case, sewage treatment consisted in entry of household sewage into a prepared surface which was previously subject to mechanical purification. All the sections were sown with grass mixture and plantings of poplar were used. Observations were made during the period of 17 years. The effluents entered onto the surface of the sections and the effluents outflowing from the facility were subject to a physicochemical analysis in order to determine the operational efficiency of a plant - soil treatment system. Also, a threefold inventory of a forest stand was made in order to determine the increment in trees.The last inventory was made in 2014. Based on dendrological characteristics, the average volume of wood mass obtained from the land irrigated with effluents was assessed.A rational management of effluents on the grounds without any central drainage allows for a parallel solution to some problems. First of all, purification of effluents in a natural environment by closing the matter cycle, and additionally contributing to the limitation of carbon dioxide emission by its halting in plant biomass.

The latest research focused on the analysis of algal growth and the dynamics of their growth use the laser diffraction technique, enabling determination of the volume fraction of suspended particles with specific diameters in aqueous solution as well as their fractal dimensions. This study focuses on the possibility of using a laser granulometer to assess the growth dynamics of algae growing in treated wastewater in a hydroponic system, supported by artificial lighting with the use of light-emitting diodes (LEDs). On the basis of the measurements, the fractal dimension (Df) of algae was determined. An attempt was made to apply the modified Avrami equation describing the crystallization process for the analysis of algae growth dynamics in wastewater. Presented results show that the fractal dimension of suspended matter, largely created by algae, in the case of additional lighting of the hydroponic system at night, takes lower values (Df ~ 1.0) than in sewage without additional light source (Df ~ 2.0). In each measurement series, the fractal dimension of particles in the tank with lighting in the end of the experiment was about 33-43% lower than in the tank without LEDs. The analysis of changes in particle diameters calculated on the basis of Avrami equation largely corresponds with the stages of algae growth. During the measurement series with lower air temperatures, the growth of algae in the tank with additional light was faster than in the tank without LEDs. The obtained information can be the basis for determining the effective method of removing algae from wastewater treated in the hydroponic system, before they are discharged to the receiver in order to prevent the outflow of increased concentrations of total suspended solids.

The subject of the study was to estimate the quality of shallow groundwater from wells which are the source of drinking water. The study included 8 wells located in the municipality of Gorzyce. The results are presented as medium concentrations of the analyzed components during one year of observation. The results confirm that poorly protected wells are characterized by poorer quality water. In most of the analyzed cases, the average concentration of pollution indexes (this applies particularly to iron and manganese concentration) exceed the limits established for drinking water.

Municipal wastewater is characterized by diverse microbial content, largely dependent on their sources as well as many other factors like condition and health of their producer, but also environmental factors. The number and share of individual bacterial population in wastewater is changing during the process of their treatment in wastewater treatment plants. The microbial content of treated wastewater is significantly affected by the type of technology used for wastewater treatment. The paper presents the results of the species composition of bacteria present in the wastewater at various stages of treatment for the two different technologies. Samples of wastewater from hydroponic wastewater treatment plant and from the plant which technology is based on biofilters were analysed. A key mechanism for wastewater treatment in both cases is biological treatment, using microbial activity that decomposes pollutants in the wastewater, which significantly contributes to changes in the species composition of bacteria comparing to microbiological composition of sewage flowing into the treatment plant. Analyses of microbial composition showed that in the objects consisting of preliminary tank and biofilter, composition of bacteria species is changing, but many species isolated from raw sewage is also found in treated wastewater. In the plant with hydroponic lagoon after wastewater treatment throughout the process system, bacteria present in raw sewage or in wastewater after biological treatment were not identified in the outlet.

The study presents the results of the treatment of domestic and industrial wastewater with respect to the reduction of nitrogen and phosphorus compounds. The analysis encompasses the results of physical and chemical tests of effluents from two facilities based on hydroponic technology: wastewater treatment plants with hydroponic lagoons using the BIOPAX technology – Paczkow, Poland and the Organica technology – Szarvas, Hungary. Monthly treatment effectiveness was determined basing on these analyses. The composition of wastewater flowing into the lagoon (after mechanical treatment) and wastewater discharged to the collector in 2009–2011 was subject to physical and chemical analysis in both facilities. The effluent quality was determined basing on the concentration of total phosphorus, total nitrogen and ammonium nitrogen. Mean annual results of the operation of both objects were high. For the wastewater treatment plant in Paczkow, operating in the BIOPAX technology, the effectiveness of treatment with respect to total nitrogen throughout the analysed period ranged from 76.9–84.4%. Total phosphorus was eliminated from wastewater with an effectiveness of 96.4–98.0%. Such high reduction level was caused by the application of additional precipitation process in the chambers of activated sludge reactor. The hydroponic plant in Szarvas (Organica technology) was characterised by a high effectiveness of reduction with respect to ammonium nitrogen: 92.0–93.0%, while the reduction of total phosphorus fell into the range 49.3–55.3%.

The use of plants and natural processes for wastewater treatment is an issue that arouses interest among technologists and scientists around the world. The aim of the article was to analyze the influence of the air temperature and insolation on the removal of nitrate nitrogen from the wastewater treated in the hydroponic system, under greenhouse conditions. Samples of sewage for its quality tests were taken from a wastewater treatment plant (WWTP) located in the southwestern part of Poland. Data regarding daily sunshine duration and average daily air temperature values in selected periods of 2013–2016 come from a meteorological station located 30 km from WWTP. The conducted research and analyses of the results clearly indicate that under moderate climate conditions, the amount of solar radiation reaching the Earth’s surface is insufficient to ensure the year-round, effective wastewater treatment process in the hydroponic system. In the case of air temperature, no correlation was found between the tested parameters, which indicates the lack of temperature influence on the efficiency of NO3 removal from the wastewater by macrophytes growing in the lagoon.

Due to a lack of centralized water supply network on rural areas, the main source of water for household use are shallow dug wells. The quality of water taken in this way is not a subject of law regulations in Poland which are connected with quality of water taken for human consumption, which is the reason why this kind of water do not often meet the standards. Wells that are no longer exploited by taking water for living purposes because of households’ connection to the central water supply, are becoming a problem The paper presents the results of physicochemical composition of water samples taken from shallow dug wells located on the rural areas. The concentrations of mineral forms of nitrogen, i.e. nitrates, nitrites further the concentrations of ammonia nitrogen and phosphate were analysed. Additionally, changes of pH and conductivity were measured. In the case of nitrate and nitrite highest concentrations exceeding the standards contained in the Regulation of the Minister of Health were observed in wells 1 and 3. During the study period, seasonal variation of concentrations of ammonium nitrogen were observed as reflected in the increase of the parameter in winter months. Ammonium was also an indicator whose concentrations exceeded regulated norms at least once during the research period in each of the tested wells. Phosphates concentrations in the analyzed samples were at the level 0.12–0.17 mg PO4/dm3.

In this article distribution of monthly phosphorus loads flowing out of two agricultural catchments which are located in different physiographic conditions of Lower Silesia was analysed. Loads of phosphorus runoff from the catchment located in the piedmont part of Lower Silesia in each month rarely exceed 0.10 kg P ∙ ha-1. The size of annual load is determined by loads obtained in two months of early spring. Much lower loads obtained for lowland catchment, located near Wroclaw. Values ​​calculated for each month rarely exceed the value of 0.01 kg P ∙ ha-1. Culmination of loads bringing away is a bit more extended in a time compared to the catchment located on Sudety Mts. Foreland. Much higher loads are observed during the period from January to April – this period has a major impact on the size of phosphorus load that flows out from this catchment during whole hydrological year. The obtained results clearly indicate that the threat of watercourses and water reservoirs supply in phosphorus compounds from agricultural land is periodic and it is particularly high during early spring. Phosphorus load flowing out from the analyzed catchments is very diverse. From facility located on Sudety Foothill in hydrological year, during research period, flowed away average 0.81 kg P ∙ ha-1. Significantly lower values were obtained for second facility and it was average 0.15 kg P ∙ ha-1 during a year. The size of load discharged during a year is largely determined by amount of phosphorus load flowing out during winter half of the year (from XI to IV). In case of foothill catchment in this period flowed out average 0.56 kg P ∙ ha-1, which presents 69% of annual load and in lowland catchment this percentage was even slightly higher and was 73%.

The aim of the study was to determine the changes in suspension particle size identified in biologically treated wastewater, which was then treated in hydroponic system with use of engineering lighting by the light-emitting diodes (LED). The study was subjected to wastewater purified under laboratory conditions, in a hydroponic system using the effect of macrophytes Pistia stratiotes and growing algae. Measurement of particle size was made using a laser granulometer. Analysis of the results showed that the additional lighting of the hydroponic system with LED can significantly influence the ability of the suspension particles to agglomerate and, consequently, determine their sedimentation properties. In hydroponic system supported by additional lighting, more particles were observed with equivalent diameter D(3.2) smaller than 10 μm than those in the tank without additional lighting, indicating a higher reactivity of the particles. Determining the size of equivalent diameters D(4.3) allowed us to observe that in hydroponic system, particles of relatively small size predominate, which negatively affects the sedimentation process of the suspensions. Determination of particle size of suspensions consisting mainly of algae and the dynamics of their changes are the basis for specification of an effective method of removing particles from the system to protect the receiver from excessive suspension concentrations.

The paper presents results of research concerning operating of five small wastewater treatment plants working in two different technologies: hydrobotanical wastewater treatment plant and constructed wetland. Each object was designed for the treatment of domestic sewage after preliminary mechanical treatment in a septic tank. Hydrobotanical wastewater treatment plants and one of constructed wetland beds were built for treating sewage produced in educational institutions and resort. In the article attention is paid to possibility of exceeding the maximum allowable concentration of pollutants for three main indicators of pollution: BOD5, COD, and total suspension. The reduction of these indices is required by the Regulation of the Minister of Environment [14] for wastewater treatment plants with PE < 2000. In addition, the paper presents the effects of wastewater treatment to reduce biogens. The best quality of outflow was reached by outflows from constructed wetland treatment plants. None of the observed objects fulfilled the requirements in terms of allowable concentrations for total suspension. The most effective were objects operating in technology of “constructed wetland”.

The paper presents the impact assessment of the plant-soil treatment plant on the groundwater quality. The physicochemical composition of groundwater was analysed. The samples were collected form the piezometer network located in the irrigated area and around it. Water quality tests were carried out in 2014 with the frequency of the month. Changes in the physicochemical composition of groundwater were determined with reference to quality of domestic wastewater used for irrigation. The obtained results were also referred to groundwater parameters limits before the facility’s operation started. As a result of many years of exploitation the groundwater quality under the irrigated area has changed. The boundary of individual segments of wastewater treatment plant is clearly marked by the change in concentrations of the observed pollution indicators. The highest values of organic matter expressed by BOD and COD were observed in the groundwater the I segment (respectively 6.9 gO2·m-3 and 66.2 gO2·m-3). This was the results of a change in the irrigation regime. As the result of irrigation, an increase of nitrate (V) and nitrate (III) was also observed in comparison to their pre-operational values. Plant-soil treatment plant prove high effectiveness of work. However, due to their significant impact on the groundwater quality their operating should be gradually reduced.

Constructed wetlands, commonly known as ground filters, are well suited mostly for wastewater treatment in areas with no central sewage system. The basic difficulty with exploitation of constructed wetlands is connected with irregular hydraulic overload of its surface. However, irregular wastewater inflow can be reduced by cyclical irrigation which increases efficiency. The unquestionable advantage of the constructed wetlands is inexpensive construction and exploitation as well as low energy consumption. The constructed wetlands also fit very well in surrounding area. The investigation concerned the analysis of two constructed wetlands which are composed of mechanical separation (septic tank) and a filter bed with subsurface flow. The research has been undertaken in a period from July to December 2008, with regard to concentration distribution of nitrogen compounds in municipal sewage after constructed wetlands. The preliminary investigation on constructed wetland which has been exploited for 10 years showed variable removal efficiency of nitrogen compounds. The continuation of the research can indicate the efficiency of wastewater treatment in summer and winter season.