Data for: particle size analysis and contamination indices

Twenty-one soil samples taken from nine historic abandoned gold mine solid waste dump sites in the Witwatersrand Basin of South Africa were screened from a depth of 30-120 cm. On average, the particle size was 60% sand, 13% silt and 27% clay (Table S1). Metal content (mg/kg) was measured using inductively coupled plasma emission spectroscopy and reported as Pb (774.02) > As-metalloid (52.01) > U (13.89) > Ag (8.73) > Sn (2.09) > Tl (1.94) > Cd (0.20). Hg (331.61) > Au (17.84) were measured in µg/kg. The average values (mg/kg) of soluble inorganic anions were SO42- (3726.17) > NO3- (903.56) > CN- (t) (64.68) > PO43- (10.74) > NO2- (7.22). The average pH was measured at 3.89 and the EC was measured at 222.94 mS/m.

Contamination factor (CF) and pollution load index (PLI) were calculated from elemental data. CF varied between various elements, from just 0.003 in one tailing to 333.500 in the next (Table S2). PLI varied from 0.289 to 2.128 between tailing dumps (Table S2). Uncontaminated sites include CF < 1 and PLI < 0. Soil screening values (SSV) (mg/kg) are Pb (2.20-7070), As (0.20-11), Hg (0.06 –2630), U (1–69), SO42- (951–8355) and CN- ( 0.51–488.25), and exceeded international soil intervention standards. NO3- (5–16,000 mg/kg) exceeded South Africa's protective water resource and informal residential area recommendations. Descriptive statistics are shown in Table S3, with the standard deviation changing significantly from 0.34 to 2149.52.

在南非维特瓦特斯兰德盆地的九处历史废弃金矿固体废物堆场，共采集了二十一份土壤样本，深度介于30-120厘米之间。平均而言，样本的颗粒组成中60%为沙，13%为粉砂，27%为粘土（见表S1）。金属含量（mg/kg）通过电感耦合等离子体发射光谱法进行测定，报告结果为Pb（774.02）> As-金属（52.01）> U（13.89）> Ag（8.73）> Sn（2.09）> Tl（1.94）> Cd（0.20）。Hg（331.61）> Au（17.84）的测量值为µg/kg。可溶性无机阴离子的平均含量（mg/kg）为SO42-（3726.17）> NO3-（903.56）> CN-（t）（64.68）> PO43-（10.74）> NO2-（7.22）。平均pH值为3.89，电导率（EC）为222.94 mS/m。