According to the remediation completion report, it was determined that the remediation programs had largely been implemented; however, the process was not fully concluded due to residual point-source contamination.

Additional analyses and precise cost estimation (2018) In 2018

The City of Šibenik engaged the company OIKON d.o.o. Zagreb to conduct new investigative works and analyses at sites identified in the 2014 report as having contamination levels exceeding permissible limits.

The analysis results showed the following:

• Identified sites: Two instances of residual point-source contamination failing to meet requirements were identified (the tar pit site and its surrounding area);
• Financial estimate: The costs for completing the remediation were estimated at between €76,881 and €121,131;
• Fund reservation: Batižele d.o.o. reserved the maximum estimated amount of €121,131 in its balance sheet.

On April 16, 2018, the Ministry of Environmental Protection and Energy confirmed that all previously issued documents remained valid and that there was no need to adopt a new remediation program.

Cooperation with the EBRD and independent international analysis (2023)

The issue of completing the zone's remediation was integrated into the terms of reference for Phase II – Urban regeneration of the Šibenik brownfield site. Within the scope of this project, Batižele d.o.o. prepared an international, competitive, and transparent tender in cooperation with the European Bank for Reconstruction and Development (EBRD) and a team of consultants.

The EBRD engaged the independent, internationally recognized consultancy firm ARUP, which conducted an updated analysis of the land. Fieldwork (sampling of seawater, sediment, soil, groundwater, and slag) was carried out by Geotehnički studio from Zagreb.

The report from May 2023 confirmed the following:

• No significant soil contamination was found that would require additional excavation and removal of material from the site;
• Due to the natural presence of metals and polycyclic aromatic hydrocarbons (PAHs), ARUP recommended applying a new, clean layer of soil to all open (green) areas where no buildings or solid surfaces are planned.

Final remediation works and standards

According to the ARUP analysis, the final remediation works specifically comprise:

1. Slag removal: Removal of approximately 30,000 m³ of slag from the site;
2. Remediation of three specific locations: Additional soil works detailed in the Oikon report (2018), accompanied by verification of compliance, to meet all regulatory requirements;
3. Ongoing monitoring: Removal of any localized contamination detected during the construction works themselves
4. Green areas: Covering all soft landscaping areas with a clean, imported soil layer to a minimum depth of 600 mm.

These works are defined in accordance with international best practice and the reference standards of the Kingdom of the Netherlands (Dutch Soil Remediation Circular, 2013), which was also the standard required in the tender documentation.