Fig. 1. Distribution of the sampling points in the abandoned shipyard area (site A). X: sediment sample; ○: soil sample; □: subsoil sample (3–20 m depth below ground). Site B, Sai Kung.

Fig. 2. Ammonium bicarbonate-diethylenetriaminepentaacetic acid (DTPA)-extractability of metals in the abandoned shipyard and Sai Kung coastal soil.

Fig. 3. The in vitro acute toxicities of the abandoned shipyard soils on plants, bacteria and fungi.

Physio-chemical properties of the soil samples of the abandoned shipyard area and clean coastal soil

Samples 1–6: surface soil; 7–9: subsoil dredged at 3, 10 and 20 m depth, respectively. SK: clean coastal (surface) soil collected in Sai Kung, New Territories, Hong Kong. Five soil samples were collected in a sampling point.

Total metal contents of the soil samples of the abandoned shipyard area and clean coastal soil

Sampling point, number, site in abandoned shipyard area; SK, Sai Kung coastal soil. Five soil samples were collected in a sampling point.

^*Chromium (III) + chromium (IV) contents.

RBC, Risk-based concentration for soil corresponding to the target risk or hazard quotient (USEPA; http://www.epa.gov/reg3hwmd/risk/human/index.htm).

Region III SSLs, Region III Superfund site soil screening levels (SSLs) for soil-to-groundwater migration (USEPA).

Dutch New List for intervention values for immediate remediation.

Organopollutants of soil samples of the abandoned shipyard area

RBC, Risk-based concentration for soil corresponding to the target risk or hazard quotient (USEPA; http://www.epa.gov/reg3hwmd/risk/human/index.htm).

Region III SSLs, Region III Superfund site soil screening levels (SSLs) for soil-to-groundwater migration (USEPA).

Dutch levels: B, potential pollution present and requires further investigation or remediation; C, Pollution which requires remediation. Dutch New List for target values and intervention values (mg kg⁻¹) for soil with organic matter <10%: total PAHs, 1, 40; ∑DDT, 0.01, 4.

TCLP metals of the abandoned shipyard soil

TCLP, a toxicity characteristic leaching procedure (USEPA Test method); UTS, the Universal Treatment Standards of U.S. Resources Conservation and Recovery Act to remediate metal contaminants.

(a) Basic physio-chemical properties of the sediment samples of the abandoned shipyard site and (b) total and ammonium bicarbonate-diethylenetriaminepentaacetic acid (DTPA)-extractable metals in sediments

Sediment criteria: LCEL, lower chemical exceedance level; UCEL, upper chemical exceedance level (Dawes, 2001).