Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: czas przepływu wody

Sortuj według:

Ogranicz wyniki do:

Assessment of river water infiltration conditions based on both chloride mass-balance and hydrogeological setting: the Krajkowo riverbank filtration site (Poland)

Gorski Jozef, Dragon Krzysztof, Kruc-Fijalkowska Roksana, Matusiak Magdalena

Geologos

2021

Vol. 27, No. 1

35--41

In the present work measurements of chloride concentrations were used to assess the variability of infiltration conditions and contributions of surface water and local groundwater to the discharge of wells at Krajkowo riverbank filtration site (western Poland). Tests were performed on samples from 26 wells located in a well gallery close to the River Warta. Due to higher chloride concentrations in river water in comparison with local groundwater, significant differences in concentrations in samples from individual wells were noted. In particular, lower chloride concentrations in 11 wells were recorded, which can be linked to the local occurrence of low-permeability deposits in the superficial zone; a locally higher degree of riverbed sediment clogging in the highly convex meandering zone, where strong erosion of the riverbed occurred, which in turn led to increased clogging; the occurrence of a more intensive groundwater inflow into the river valley due to water infiltration from a smaller river entering the River Warta valley, as well as unfavourable conditions for the infiltration of surface water to the lower part of the aquifer with a greater thickness. Differences in chloride concentrations observed were also used to quantify approximately river water contribution to the well production. The average contribution of the River Warta to the recharge of the entire well gallery was estimated at 59.8%.

Niektóre nieprawidłowości w obliczeniach czasu przesączania wody podziemnej przez pakiet warstw w strefie saturacji

Hauryłkiewicz J.

Przegląd Geologiczny

2005

Vol. 53, nr 8

668--672

Legal permits concerning water usage often contain improperly calculated time of vertical seepage through a pack of homogeneous layers in the saturated zone.. Usually the following mistakes against the rules of hydraulics are made: (1) it is assumed that hydraulic gradient in each layer of the package is equal to the gradient corresponding to the package as a whole; (2)the formula used is wrong because it is based on inadequate assumption, (3) the formula is right but is not used in correct way, (4) time duration of flow through the layer of high permeability is neglected, (5) too high value of the active porosity is assumed. An example is shown comparing the incorrect calculations with the ones consistent with the hydraulics laws. Some of the above mistakes result in significant underestimation of the seepage time (up to 60 % in the example used), some others overestimate the time, hence they affect the correctness of implementation of Polish Water Law concerning protection zones of water intakes and lead to improper administrative decisions.