Limnology; Water quality; Abandoned quarries
Limnological conditions were studied in two abandoned granite quarries in George Friedrich Park, St. Cloud, Minn. These quarries were excavated from 1886 to 1890 and left shallow due to inadequate water pumping systems at the time. The quarries were less than one hectare in area and had mean depths of 7.3 and 8.2 m. The annual heat budget was about the same for both quarries, 10,535 gm. cal/cm•. Concentrations of [chemical symbols] were determined. Very low concentrations of nitrate nitrogen were found ([chemical symbols]). The hypomimia of both quarries contained hydrogen sulfide throughout the study. Data show West Quarry to be meromictic while East Quarry was holomictic. With no outlet, except seepage, salts accumulated through the years, partially accounting for the eutrophic nature and chemical concentration of the quarries. Eutrophication was essentially artificial, from the addition of debris.
Knutson, K. M.
Morphology and Water Quality in Three Abandoned Granite Quarries.
Journal of the Minnesota Academy of Science, Vol. 35 No.2, 107-110.
Retrieved from https://digitalcommons.morris.umn.edu/jmas/vol35/iss2/14