The La Rocque borehole recently drilled for research purposes was a success would the Minister advise what the drilling of the borehole has achieved and its future usefulness

2.2   Deputy G.C.L. Baudains of St. Clement of the Minister for Planning and Environment regarding the borehole at La Rocque drilled for research purposes:

Following the Minister's statement that he is satisfied that the La Rocque borehole recently drilled for research purposes was a success, would he inform Members precisely what the drilling of the borehole has achieved and its future usefulness?

Senator F.E. Cohen (The Minister for Planning and Environment):

The La Rocque borehole was part of an investigation. It was discussed in detail and agreed by all members of the Deep Groundwater Advisory Group within a signed formal agreement. The Deep Groundwater Advisory Group was tasked to take this evidence-based approach as to the origin and magnitude of Jersey's deep groundwater resources by the former Environment and Public Services Committee, an action that I fully support. This followed a recommendation from the Shadow Scrutiny Panel in their report on the Draft Water Resources (Jersey) Law. The British Geological Survey and Entec U.K. Limited who had contributed to the Shadow Scrutiny Panel were appointed by the Deep Groundwater Advisory Group to oversee and quality-assure the investigation. Mr. George Langlois and Mr. Lewis de la Haye are both valued members of the group. They agreed to identify 2 sites where underground streams entering the Island could be intercepted. The identified sites were at La Rocque and St. Catherine. During drilling, all parameters that may indicate the presence of an underground stream were recorded and sampled. Once the borehole was complete hydraulic testing took place to determine the yield with, again, exhaustive sampling being undertaken. The investigation at La Rocque clearly showed that: (1) no significant increase in groundwater flow or underground stream was found at any depth; (2) the underground water at depth was hydraulically connected to shallow underground waters; (3) the isotopic signatures and the inorganic chemistry of the groundwater did not change at any depth and were consistent with a groundwater source originating as rain in Jersey. The results are confirmed and supported by findings at the St. Catherine test borehole. The investigation, therefore, concludes there is no evidence to suggest the existence of a separate deepwater resource that flows from outside the Island. The information obtained from this deep groundwater investigation has allowed a conclusion to the debate. Regarding the question as to the future usefulness of the bore, the borehole is on private land; the future use would be a matter for the landowner. Finally, I would draw Deputy Baudains' attention to the summary report of this work which all Members have

received and to the more detailed technical report which is available by request from my

department or from our website. Thank you.

1. Deputy G.C.L. Baudains:

Would the Minister confirm that the La Rocque borehole is 55 metres deep but completely blocked with debris approximately two-thirds of the way down and, therefore, cannot be used to supply water, and probably unlikely to be able to supply useful samples either? Would he further confirm

that the methodology chosen to determine whether water comes from France to Jersey is incapable of making that differentiation? Perhaps the Minister would also give us his definition of the word "success".

Senator F.E. Cohen:

I can confirm that the La Rocque borehole was drilled to a final depth of 55.5 metres and, for further clarification, that the St. Catherine borehole was drilled to a depth of 79.5 metres. The borehole was not blocked at the time that the tests were carried out. I understand that one of the boreholes required clearing to allow the hydraulic tests to be carried out, which was a secondary measure, but both the British Geological Survey and Entec are entirely satisfied that the tests are satisfactory and the results are conclusive. I am satisfied that the methodology used and approved by the British Geological Survey and Entec was the best possible methodology to bring this matter to a conclusion. While I accept that the Deputy has long held views in relation to water connections with France, and that others hold similar views, I believe that having spent public money on delivering these tests and having had a conclusive result that it is time to move on now and preserve our water resources for future generations.

2. Deputy G.C.L. Baudains:

The conclusive result which the Minister refers to, would he confirm that the isotopic signature of the water at La Rocque is the same as that of nearby France?

Senator F.E. Cohen:

I can only confirm that the isotopic signature at the bottom of the borehole is virtually identical to the isotopic signature at the top of the borehole and that the conclusion of the British Geological Survey and Entec Limited have been that this indicates with certainty that the water at the bottom of the borehole came from the same source as the water at the top of the borehole. Therefore, their conclusion is that it is rainwater that fell on the surface of Jersey.

3. Deputy S.C. Ferguson of St. Brelade :

Would the Minister like to confirm that he has had a reply from Entec and the B.G.S. (British Geological Society) on the age of the water in the bores? Would he not agree that more work on the quantity of water below the Island needs to be done, particularly in view of the fact that a small number of 750 foot boreholes supply 100,000 people in France? It does look as if we need some deeper bores to ascertain how much water there is.

Senator F.E. Cohen:

I can confirm that the final aging reports have not been received and the information that I was provided with yesterday indicates that this will be available within 2 weeks. As soon as it is

available I will of course immediately distribute it to all States' Members. As to the question of more work required, the Deep Groundwater Advisory Group agreed that these would be definitive tests in that the water diviners were given the opportunity of choosing the particular sites that they believed would allow us to drill into the deep underground streams they believed existed from France.  We carried out the tests. Entec and the British Geological Survey are entirely satisfied that the results conclusively show there is no water connection but, very clearly, if we were to do additional testing that additional testing would provide further information but I certainly do not believe that it would add to the conclusions or change in any way the conclusions of the British Geological Survey or Entec which are 100 per cent unequivocal.

4. Senator S. Syvret (Minister for Health and Social Services):

Would the Minister agree with me that we now have a definitive answer to this issue and the time has arrived for us to stop wasting taxpayers' money chasing pixies around the bottom of the garden and to stop wasting the time of this Assembly and finally put this matter to bed?

Senator F.E. Cohen:

I think that we have a 100 per cent test.  I think that the results of that test are very clear to all. That is, that the British Geological Survey and Entec both agree that there are no underground water connections with France. I will, therefore, be pressing forward as soon as possible with a Water Resources Law, albeit that it will be significantly changed from the previous draft, in that domestic boreholes will be entirely exempt from any licensing and fees and that the thresholds will be very significantly increased. The current proposal is around 15 cubic metres per day. But, yes, I agree, Sir, it is time to move on. I do, however, accept and I understand and respect the views of Deputy Baudains and others that having spent public money and having had a conclusive result it is time to move on.

5. Deputy G.C.L. Baudains:

Unfortunately the Minister neglected to answer a previous question. I asked whether he could confirm that the isotopic signature for the water in the La Rocque bore was the same as the isotopic signature of water  from nearby France. He did tell us, Sir, that the signature was the same apparently at the top and the bottom of the hole although I noticed a chemical analysis is entirely different. Could he confirm that in actual fact the signature is the same as water from nearby France?

Senator F.E. Cohen:

I am not able to confirm that because I do not have the figures to hand. I will get the exact figures and I will ensure that the Deputy has them within the next 24 hours. But I think that the question is not whether the isotopic signature is the same as a particular area in France or any other particular area. It is a question of the combined tests. The combined tests clearly show, as supported by Entec and the British Geological Survey, that there is no underground water connection with France.  I am sure that aging, when we get the results, will add to this information.