Abstract

Diesel is used in onshore salt-mining in the Netherlands. A thin layer of diesel is used as a blanket on the brine that is produced by injecting water into layers of salt deep under the ground. This thin layer of diesel prevents the collapse of the caverns that form underground.

As part of the mandatory REACH registration of dossiers for the diesels used in salt-mining, this specific application of diesel is not identified. Under the European regulation on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH), all applications of a chemical should be identified in the dossier for that substance. The absence of this specific application makes it difficult to quantify the risks involved and the risk management measures that are necessary. Another obligation within REACH that is also not met, is the availability of exposure scenarios for each identified use of a substance. Applications of diesel other than those mentioned in the registration dossier and the Safety Data Sheet are not recommended by the suppliers of the diesel used in salt-mining in the Netherlands.

However, this does not mean that the three Dutch companies that use diesel as a blanketing oil in salt-mining have not taken steps to mitigate the risks to the public health, workers and the environment. RIVM advises the Dutch State Supervisor for Mines (SodM) to commission research into the potential risks of the unregistered use of diesel in onshore salt-mining.

SodM has granted permits to three companies in the Netherlands to operate onshore salt mines in this manner. The permits issued state that the permit holders must comply with their obligations under REACH. If the specific application of a substance is not identified by the registrant of that substance, the downstream user must ask the registrant to identify this application by adding it to the registration dossier. For the registrant, this implies an obligation to assess whether that specific application is safe and under which conditions this is the case, as well as the obligation to prepare an exposure scenario (health and environment) for this new application, accompanied by risk management measures to guarantee safe usage.

If the application is not identified by the registrant and the registrant is unwilling or unable to do this, the downstream user must carry out a chemical risk assessment, resulting in a DU-CSR, implement the risk management measures mentioned in the DU-CSR, and notify the European Chemicals Agency ECHA of this DU-CSR for this newly identified application by means of a downstream user report.

In the Netherlands, one of the three permit holders for onshore salt-mining has notified the ECHA of the use of diesel in their solution mining operations. For the other two companies, no downstream user report was available at ECHA.