The impacts of groundwater heat pumps on urban shallow groundwater quality in Shenyang China

Abstract

In order to assess the impacts of groundwater heat pumps on urban shallow groundwater quality in Shenyang China, the urban groundwater samples from pumping and recharging wells of groundwater heat pumps were collected during heating season in the months of November, September, January, February and March in 2007 and 2008. 17 groundwater quality parameters were analyzed using Chinese state or professional standard laboratory methods and procedures. The results show that temperature, pH and the concentrations of total dissolved solid (TDS), total mineralization of groundwater (TMG), chloride (Cl), total hardness (TH), zinc (Zn), petroleum-related pollutants (PRP) and ferrum (Fe) in pumping water were lower than that in recharging water, while the turbidity, SO₄ and fluoride showed crosscurrent. There were no changes in Mn, Cu, nitrite nitrogen and total coliforms. The total bacterial count was 1/ml average in pumping water and 0/ml average in recharging water. The sampling of urban groundwater quality is higher than Chinese groundwater quality standard grade III. The groundwater heat pumps showed little impacts on urban shallow water quality during the heating season.

Keywords: Urban shallow ground water quality, ground source heat pump, groundwater heat pumps, pumping wells, recharging wells, Shenyang