Ministry of Environment and Parks

Transcription

1 Province of British Columbia Ministry of Environment and Parks ENVIRONMENTAL Victoria British Columbia V8V 1X5 APPEAL BOARD APPEAL NO. 88/03 WASTE J U D GEM ENT In the appeal of the Cottonwood Community Asociation under the Waste Management Act and the Environment Management Act against the decision of the Director of Waste Management, dated 26 February 1988 granting approval for Gold Ridge Resources Inc., to undertake an in-situ pilot scale injection-recovery test at a site near Wingdam, British Columbia, (Permit SE35253). A P P ELL ANT Cottonwood Community Association p.a. Box 4237 Quesnel, British Columbia V2J 3J3

2 APPEAL NO. 88/03 WASTE PAGE 2 HEARING DETAILS: The hearing was held on May 1988, in Quesne1, British Columbia, before a Panel of the Environmental Appeal Board. Board members in attendance were:- Mr. H.D.C. Hunter Mr. Duncan W. Hedd1e Mrs. Marjorie Ryan - Panel Chairman - Panel Member - Panel Member Mrs. Susan Tyree of PRS (Professional Recording Services) acted as recorder of the proceedings. APPELLANT: Cottonwood Community Association P.O. Box 4237 Quesne1, British Columbia V2J 3J3 Represented by Mrs. Betsy Van Halderen RESPONDENT and PEmfIT HOLDER: Gold Ridge Resources Inc Lodge Road North Vancouver, British Columbia V7R lw7 Represented by Mr. Bryan T. Nethery, P.Eng.

3 APPEAL NO. 88/03 WASTE PAGE 4 This appeal is against approval No. SE35253 dated 26 February 1988 issued by the Director of Waste Management to Gold Ridge Resources Inc. authorising a test injection of an aqueous solution of a cyanide compound into the ground near Wingdam and the recovery thereof by pumping: The appellants are concerned that the cyanide will enter their wells and contaminate them. They are not satisfied that unreasonable damage to the environment will not occur. EVIDENCE: The respondent, Gold Ridge Resources Inc. opened the hearings and presented its case in support of the approval granted to it. Mr. Bryan T. Nethery, P.Eng., Wright Engineers Ltd. and Mr. Andrew Holmes, P.Eng., of Piteau Associates Engineering Ltd. gave evidence. The basal gravels in Lightning Creek, which flows from the Barkerville area to the Cottonwood River and hence to the Fraser River are known to be rich in placer gold. However, the gravels are deep, around 150 to 160 feet below present ground levels, they are thought to be about 8 feet thick and to vary in width. Little is known of the exact dimensions. The basal gravels are overlain by a layer of silty sand, known as 'slum', which is relatively impervious. Above the slum is a layer of silty sand and gravel and above that a layer of gravel. The basal gravels are pervious and are saturated with water under a sufficient artesian head so that at the test site near Wingdam the water will rise through a drill casing to the ground surface. This water under artesian head has foiled numerous attempts to get at the gold by conventional methods. The use of cyanide to leach gold out of gold bearing rock or out of old tailings is not new and is frequently used on the

4 APPEAL NO. 88/03 WASTE PAGE 5 surface. No one has yet used cyanide to leach gold from the gravels still in place underground. The respondent thinks this is feasible and economic and is developing the process. Like any new application of a known principle, development tests must proceed in steps. The proposed test is one such step and is intended to see if gold can be extracted safely and economically by this method. If the proposed test is satisfactory further tests and development will be required before a full scale operation can be undertaken. There are two main aspects to this test:- (a) will the gold be recoverable by this method and (b) will the cyanide be recoverable from the ground and can it then be safely destroyed. There have been two tests already using brine. In the first test, the brine was not all recovered. This was thought to be. due to the use of a very strong solution. A second test using a weaker solution indicated that the brine could be recovered. Tests were also run in a laboratory to show that the cyanide would be recoverable and could be safely neutralized. The first such test indicated that a very significant proportion of cyanide would remain in the ground. On the strength of this test the Waste Management Branch recommended rejection of the application. The Director concurred and the approval was refused. These tests appear to have been improperly performed, indeed were dangerous to the laboratory technicians. These tests were performed by a well known and well respected company. Other tests performed more properly by B.C. Research and Degussa Corporation indicated that a very high percentage of the cyanide would be recovered. On the strength of these further tests the Director issued his approval.

5 APPEAL NO. 88/03 WASTE PAGE 6 The tests will allow about 10 lbs. of the cyanide compound to be injected into the gravels. It will remain there for a period and will then be pumped out again over a period. There are test wells close to the injection well which will show the dispersion of the cyanide. An interceptor well upstream will reduce the pressure in the test area so that the flow of water will stop. When the pumping out begins, the cyanide solution will be relatively strong, but as the pumping continues, the inflow of the surrounding water to the injection well will cause the solution to be weakened. The rate of dilution is one of the objects of these tests. The extracted solution will be put into fibreglass tanks and treated, on site, to reduce the cyanide concentration to an acceptable level. After treatment the solution will be put into a tank truck. It will be carried about one-quarter mile to the exfiltration pond where it will seep through the gravel to Lightning Creek. Test wells have been installed near this exfiltration pond to monitor the seepage. The approval specifies the maximum strength to go into the exfiltration pond and the rate of inflow which is related to the flow in Lightning Creek nearby. The approval also requires the pumping to continue until the solution has been reduced to 0.3 ppm, which is less than one third of the concentration permitted to be placed in the exfiltration pond. Mr. Holmes provided two very important pieces of evidence. First he stated that the water in the gravels had a large percentage of iron in it and no dissolved oxygen and therefore is not potable. It was clear that none of the wells in the area were fed from this aquifer. Secondly although the gravels were very pervious and the water flowed through them readily, this was a relative term. The brine test indicated a flow velocity of about five metres per day. The rate of flow has no relation to the speed of flow in Lightning Creek.

6 APPEAL NO. 88/03 WASTE PAGE 7 Mrs. Betsy Van Halderen gave evidence herself and called many witnesses. Much of her evidence was directed against a full scale operation rather than a single test. She also sought to discredit the procedures leading to the approval. Plainly the first test results were suspect, but witnesses from the Federal Department of the Environment and from the Water Management Branch did not object to this trial. Their lack of objection to the test did not in any way indicate that approval for a full scale operation would be easy. Mr. Topham, a school teacher in the area read extracts from reports in the Ministry of Mines. They showed that many attempts had been made over the last century to mine the gold. In every case tunnels or raises had been flooded and abandoned. The exact extent and location of these various tunnels, shafts and raises was not known. Their presence would facilitate the escape of cyanide and speed its transfer. Mr. L. Struik of the Geological Survey of Canada stated that little was known of the bedrock geology in the area. Little is known of faulting or brittle structures all of which could cause a relative increase in permeability. Mr. Myers, a mining consultant, gave evidence of the general lack of knowledge of faults, tunnels, etc. in the area and presented alternative methods of mining the gold. Members of the Association expressed their concerns at the possibility of contamination of their wells and of contamination of Lightning Creek due to accidents. The Board visited the test site and were impressed with its size, a mere 20 metres by 30 metres. The company also demonstrated the effectiveness of the interceptor well, by closing the discharge. The water levels in the test wells and injection well rose and began

7 APPEAL NO. 88/03 WASTE PAGE 8 to flow in minutes, but the injection well stopped flowing as soon as the valve on the interceptor well was re-opened. The exfiltration pond was also viewed. There is some risk in trucking the recovered solution from the site to the pond along a public road.

8 APPEAL NO. 88/03 WASTE PAGE 9 DECISION: It must be recognized that the appeal is against an approval not a permit. The approval is for a single test or a series of tests with a stated limited amount of cyanide and for a short period. The approval itself stresses that there is no guarantee whether a further approval or a permit will be granted. The company knows that this test is only one step in a complicated process before any commercial mining by this method can begin. The Board is only concerned with the problems of this one single test. It is however well aware of some of the problems which the company will have to address satisfactorily before it will obtain a full operation permit. The Board is satisfied that.the local inhabitants will not be put at risk by this test. However, they are entitled to assurances that their concerns are being watched. Community The Board therefore rejects the appeal of the Cottonwood Association. The Board directs the Director of Waste Management to amend the approval given on 26 February 1988 in the following manner:- 1. Delete the third paragraph on page 1 of the approval and substitute: - "The test shall be carried out during the period from 20 June 1988 to 01 October 1988 and the following conditions shall apply." 2. Add as condition 8(k):- "Subject to obtaining the consent of the owner, the domestic wells of Mrs. McGuire, Mrs. Anderson and Mrs. Van Halderen, shall be monitored before the test begins, once every two weeks after the test begins for six months, and once per month for a further six months."

9 APPEAL NO. 88/03 WASTE PAGE Add as clause 9:- All chemicals on the test site or laboratory shall be kept under lock and key and the site shall not be left unmanned at any time from the time cyanide is brought onto the site until the pumpout test is completed. 4. Add as clause 10:- The analysis of the wells required by Clause 8(k) shall be given promptly to the well owner. A copy of the approved contingency plan shall be provided to the Cottonwood Community Association and the Association shall be notified when the pumping out is completed. H.D.C. Hunter Panel Chairman Environmental Appeal Board Victoria, British Columbia 20 June 1988