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JUr~-19-1°99 12~T' F.OiNGEF.BE9 JChraSOrisUrONS U07 58 5252 P. 19 •.. • groundwater contamination. Thu contamination would then become the baseline data far future consideration and therefore inaccurately depicts the true characteristic of groundwater quality. During the drilling proc:ss, the zones between the different aqueous zones would be exposed to each other. Without previous study, it would be diffi~vlt w assess whether contamination within these zones has occurrtd. The only method available to protect communication between zones is to case each aqueous zone so that it is isolated and cemented back to the Surface then:by prevenIIng communication between zones. Because cementing to isolate an aqueous lone is dirYicult, it should be tarried out and certified by professional, qualified outfits. Failure to properly rase a well transitioning through an aqueous zone would allow fur cammunicaGOn between the aqueous layers. Case in point, the Agpiitant is planning on converging holes drilled for core sampling to sampling wells (Groundwater and Surface Monitoring Plan: -Appendix A; Completion detail Ameairan Sada -20-10). Once the potential for eommunicatiaa between the aquifers has been minimized the potential for contamination during well development must theft be considered. If the Applicant develops the well without a nitrogen blanket, the opportunity for liquid to dissolve a path up toward the aquifers exist. Even if a nitrogen blanltet is used, the potential still exists for aquifer eonramination. Ia this instance, as the cavern develops out vertically, Iedges of shale could block nitrogen allowing water to dissolve down and around the ledge. Once this occurs, solution is free to dissaive up along the vertical path of any sodium deposit until it makes it way to the aquifer layer. Regardless, since sa little is ]mown about solution mining under the conditions proposed by the Applicant, baseline data must be accurate to protect the aquifers and water quality as defined in the statutory tequiremenU of the Colorado Mined Land Reclamation Act. OT}3ER TECAHICAL GROUNDS FOR O$IECTION Beyond the issues sturonnding concurrent development of wells and proper well completion practices, other conseras exist which jeopardize an accurate baseline chatacierizatiun. We stress once: again, a purpose of the reclamation petrol[ is to protect hydrogeological resources. In order to due so, an accurate charactraization of that resource must be developed first, using proper well completion techniques and free of influences from the proposed futon: mining activities. Our concerns are as follows: 1. [Disposal Well Ialitrmee On Baseline Data) There has been no mentimt of the Applicant's operational disposal well in the AAI l.,mttndwater and SurFar^ Water MDnit01711g Plan err in the original DMG 112 Application. These has been no discussion or response from the DMG related to the fad that the Appli©nt is injecting highly concentrated saline solutions via a disposal well into the Lower Aquifer without any concern far the potential adverse effecu from this practice. Since baseline data has not been developed, this practice is already influencng the baseline against which the Applicant would 6e judged. Furthermore, the impact on water quality and aquifer pressure gradients is not understood. This practice should not be allowed given that the baseline water quality data is not yet developed.