Land available for port development can fall into five main categories:
- A greenfield is green, clean and pristine land that has never been developed, such as woodland, wetland and farmland. However, farmland might not be considered as greenfields if pesticides and herbicides have been used intensively for a longer period of time.
- A brownfield is a property of which the expansion, redevelopment, or reuse may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant. Thus, a brownfield is a set of neglected and underused land that was used in the past for industrial or commercial purposes and has therefore been damaged or contaminated to such an extent that it can only be (re)used by means of structural measures.
- Blackfields are also underused areas where redevelopment is needed, but where – unlike brownfields – the soil is so heavily contaminated that project developers and investors no longer see the possibility of a profitable project. In these cases, it is therefore up to the government to take initiatives, otherwise no redevelopment or regeneration of these lands will take place. Thus, the difference between blackfields and brownfields can be seen in the question of who can carry out the remediation. In the case of blackfields, the contamination is so severe that a private party will never invest because the remediation costs are too high.
- Greyfields are areas that have been developed and then abandoned. The difference between a greyfield and a brownfield is that environmental liabilities are likely not a concern.
- Bluefields are waterfront sites alongside rivers, oceans, or lakes, with high flooding risks and subjected to extensive ecological laws. As bluefield areas are subjected to flooding and stormwater issues, reviving or reusing these sites may face issues such as soil instability, continued flooding, or property reuse restrictions.
Considering the above, three main approaches can be followed in view of the remediation of a contaminated port site: (a) the government or public agency solves the problem such as in the case of blackfields; (b) the problem is solved through cooperation between public and private partners; (c) the contamination is solved entirely using private means.