Subsea works, underwater UXO clearance and hyperbaric operations.
SEMTEC, the subsea subsidiary of DEMINETEC Group, brings underwater inspection, marine UXO clearance and hyperbaric works expertise to the port and industrial community of Jakarta (Indonesia). Our Class II commercial divers — certified under French Decree 2011-45 (hyperbaric class B) and trained to NEDEX/EOD standards — operate on harbours, marine structures, ships' hulls and coastal areas contaminated by 20th-century conflicts.
Jakarta — then Batavia — was occupied by Imperial Japanese forces from March 1942 to August 1945. The Battle of the Java Sea (February 1942), Allied air raids in 1944-1945 and the Indonesian War of Independence (1945-1949) against Dutch forces left a significant unexploded-ordnance legacy in the harbour of Tanjung Priok, the former Dutch military estates and along the Java Sea coast.
Indonesia's vast EEZ contains numerous WWII naval wrecks loaded with ordnance — including HMS Exeter, HMS Encounter, HMNLS De Ruyter, HMNLS Java and several Japanese transports — which remain documented underwater UXO hazards. Indonesian Navy EOD units (Dinas Penyelaman Bawah Air, Yon Taifib) handle clearance in territorial waters.
Jakarta's mega-projects — MRT North-South Line phase 2, LRT extensions, the planned capital relocation to Nusantara in East Kalimantan, Patimban deep-sea port, offshore oil and gas projects (Sakakemang, Tangguh) — increasingly require UXO desk studies and underwater magnetometric surveys aligned with IMAS standards and French Decree 2005-1325.
In-water survey by qualified divers, ultrasonic thickness through paint, 3D photogrammetry, IACS-class survey report for calls at Jakarta.
Magnetometer and gradiometer survey, target identification, controlled neutralisation or recovery in coordination with local authorities.
Wet welding, oxy-arc cutting, underwater concreting, sheet-pile and quay repair.
Refloating of sunken vessels, recovery of submerged plant, crane-assisted lifting operations.
On-site recompression chamber deployment, compliant with French Decree 2011-45 and IMCA D guidance.
In the strategic port of Jakarta, SEMTEC mobilises divers, observation ROVs and marine magnetometers to secure basins, jetties, approach channels and anchorages where 20th-century munitions still routinely lie on the seabed.
SEMTEC operates in Jakarta and across Indonesia from our French bases at La Seyne-sur-Mer (Var) and Wancourt (Pas-de-Calais), our Belgian office in Bruges and our Ukrainian site in Kyiv. Diving spread and naval logistics are mobilised on demand.
Depending on Indonesia's history, port seabeds typically conceal sea mines (German EMC, British Mark XVII), submerged aerial bombs (250 kg–500 kg), torpedoes, large-calibre naval shells and depth charges. The preliminary EHT pinpoints the expected typology for Jakarta.
Our Class II hyperbaric-class-B divers work to 50 m on air, and we coordinate longer-duration tasks down to 90 m through saturation partners. Observation ROVs extend reconnaissance to 300 m.
A standard UWILD/IWS on a commercial vessel takes 8–24 dive hours depending on hull length, complexity, coating condition and class requirements. SEMTEC issues the class report within 5 days.
Decree 2011-45 governs hyperbaric work in France. Internationally, SEMTEC uses it as a benchmark alongside IMCA D standards and the local regulations applicable in Indonesia.
For any survey, inspection or subsea intervention in Jakarta, contact our teams:
Tel: +33 (0)9 52 51 00 63
Email: contact@semtec-france.com