Questions and answers from the information meeting about gas extraction and subsidence

This approach is difficult because various disciplines are involved and it concerns a long chain of calculations. Therefore, damage assessment cannot always be done comprehensively. However, in cases with a specific cause, such as subsidence due to gas extraction, the context will be taken into account. Gas extraction is a major cause of subsidence, especially in areas such as Groningen and Tytsjerksteradiel. An integral investigation then seems necessary.

Land subsidence due to gas extraction affects the water level. This is called the 'relative groundwater level'. When land subsides, the groundwater does not sink with it, and therefore comes closer to the surface. Land subsidence is therefore a combination of factors: Gas extraction causes land subsidence, and the effect of this is that the relative groundwater level changes.

The direct damage from gas extraction itself is negligible. Damage that occurs in the context of gas extraction is often caused indirectly. This usually happens in the shallow subsurface, for example, due to changes in the groundwater level or water management. In some cases, the water board applies water level lowering. These indirect effects can lead to damage, but are related to the subsidence caused by gas extraction.

The size of a gas field does indeed influence the relative displacements (the movement) of the soil. In a large gas field, the differences in soil movement are smaller, meaning the displacements are less significant. Smaller fields contain less gas, leading to land subsidence. However, because these fields are more localized, the relative displacements in that specific area can be relatively larger. Overall, the impact remains limited.

Certainly. Given the situation in Groningen, we understand the concern when activities take place in the deep subsurface. That is why we assess each initiative separately, based on the specific circumstances. The entire context is considered. The necessary expertise is used to carefully map the expected effects. The minister only approves an extraction plan if it is truly safe.

See answer to the next question.

It is the responsibility of the Water Board to determine how they manage the groundwater level. If the Water Board wants to approach it differently, we will take that into account. In that case, it will have to be reconsidered what is and is not possible. The advisors will then assess the effects, including the impact on the groundwater level. 

The ministry has drawn up an assessment framework for this.

Assessment framework for winning plans

• Assessment based on the following aspects:
  • Systematic management of the subsurface
  • The expected subsidence.
  • The expected seismic risk.
  • The potential consequences of soil movement for people, buildings, and infrastructure.
  • There are adverse effects on nature and the environment.
• Permit/consent only if it can be done safely.

No risk doesn't really exist. We can never guarantee 100% safety. You always take as many factors into account as possible. If you do something, there is always a possible effect or consequence. It is important to look at which risk category something falls into, for example, whether the risk is negligible or whether only cosmetic damage is to be expected.

There can be several reasons to refuse a permit. An example is when the seismic risk, such as the chance of earthquakes, becomes too great. This is, for example, the reason for not granting a permit in Groningen.

The ministry only assesses the land subsidence that is estimated to result from gas extraction when processing the permit application. We do not take into account land subsidence due to peat shrinkage or oxidation. 

Shallow subsidence due to peat shrinkage or lowering of water levels by water boards, which exposes peat to air and causes further subsidence, is beyond our assessment. We only focus on the effects of gas extraction.

This falls under the responsibility of Vermilion. They are responsible for compensating the costs and damages resulting from gas extraction. In Friesland, this is assessed by the Commission for Soil Subsidence due to Natural Gas Extraction in Fryslân.

The Netherlands aims to be climate neutral by 2050. Gradually, there will be a transition from fossil fuels to sustainable energy. Currently, there is insufficient sustainable energy available. 80% of households still use natural gas, as does a large part of Dutch industry. By extracting gas in the Netherlands, we are less dependent on other countries. In addition, this causes less CO₂ emissions than imported gas during extraction and transport.

In the Netherlands, gas is extracted from approximately 200 gas fields. This contributes 30% to the national gas consumption. 

In Friesland, we have the Commission on Subsidence due to Natural Gas Extraction in Friesland (CBAF), which any government agency can join. If measures are needed because the municipality, the water board, or the province needs to carry out repair work and Vermilion is the cause or partial cause, they can submit a claim to the commission. The Commission then provides binding advice on which part of the costs will be borne by the gas producer. This damage is then actually compensated.

Mining companies no longer play a role in the claims process. Vermilion and NAM are excluded from the claims handling procedure during the submission, assessment, and settlement phases. The only role they still have is when a ruling is made and the claimant is successful. In that case, Vermilion must compensate the damage, and Vermilion has committed to this.

Vermilion is preparing a new extraction plan for a small field in the area, in which water-related issues play a role. There have been intensive preliminary consultations with the water board* to clarify the details. 

*However, this consultation took place before the Water Board had adopted the new position.

72 cents of every euro goes to the Minister of Finance (currently even more, 82 cents, due to the levy related to the energy crisis). A portion goes to the gas extraction company and another to the government, where it ends up in the general funds and is used for the Netherlands' budget.

We are now looking with the mining companies at how we will deal with the benefits and burdens in the future.

There are 2 types of zero measurements:

1. Baseline measurements were prescribed for a long time in the mining plan, whereby Vermilion was responsible for carrying out baseline measurements at various locations. The ministry, partly on the advice of experts, has stopped including this condition because, in the event of damage, the causal link between the damage and the activity must always be demonstrated. This role now lies with the Mining Damage Commission or the CABF.
2. When Vermilion carries out heavy transport operations – such as with TID-200 – the vibrations from the traffic are monitored, and baseline measurements of infrastructure and buildings are still taken.

It is good to know that this existed. You can have a good overview of the damage now and from before, but this alone does not say anything about the causes. Whether or not a zero measurement has been carried out, it is always important to first investigate whether something has happened in the subsurface that could have caused the mining damage. If it is possible within the broadly defined margins, we will have experts carefully examine every crack.

An expert can also demonstrate that an earthquake (due to mining) has aggravated existing damage. If it cannot be established that the damage was caused by other causes and we have seen in the soil that something was wrong (such as an earthquake), the decision is usually in favor of the damage reporter.

Doesn't say much. In 4 years, 500 reports have been received, with approximately 50 related to Ekehaar, Drenthe. This is the first time the commission has determined that damage was caused or worsened by a mining-related earthquake in October 2023. This has led to compensation being awarded in 14 cases, ranging from 800 to 16,000 euros. No (direct) damage from mining has yet been found due to subsidence.