Table 2.

Metal content in the tested water extract samples (for the ratio of sediment mass to water volume reaching 1:10, according to PN-G-11010:1993 under static conditions, at a temp. of 20 ± 1 °C)

Sample	Parameter	Leaching agent	Unit	Day 1	Day 7	Day 14	Day 21
Sample no. 1 Ca(OH)2 + NaOH conventional treatment	Cr	Sea water	mg/L	$69.1\pm 10.4$	$66.8\pm 10.0$	$69.7\pm 10.5$	$71.8\pm 10.8$
		Acid rain	mg/L	$63.8\pm 9.6$	$72.2\pm 10.8$	$71.8\pm 10.8$	$70.7\pm 10.6$
	Ni	Sea water	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
		Acid rain	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
	Cd	Sea water	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
		Acid rain	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
	Co	Sea water	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
		Acid rain	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
	Pb	Sea water	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
		Acid rain	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
	Cu	Sea water	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
		Acid rain	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
Sample no. 4 Ca(OH)2 + NaOH + Na2CS3	Cr	Sea water	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
		Acid rain	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
	Ni	Sea water	mg/L	$367\pm 55$	$386\pm 58$	$438\pm 66$	$466\pm 70$
		Acid rain	mg/L	$556\pm 84$	$590\pm 89$	$646\pm 97$	$724\pm 109$
	Cd	Sea water	mg/L	$1720\pm 258$	$1820\pm 273$	$1762\pm 264$	$1821\pm 273$
		Acid rain	mg/L	$1320\pm 198$	$1078\pm 162$	$952\pm 143$	$1004\pm 151$
	Co	Sea water	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
		Acid rain	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
	Pb	Sea water	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
		Acid rain	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
	Cu	Sea water	mg/L	< 0.02	< 0.02	< 0.02	< 0.02
		Acid rain	mg/L	< 0.02	< 0.02	< 0.02	< 0.02