Are you set on jet grouting, or are you exploring alternatives needing cost estimates? Most of the real expertise in jet grouting belongs to the contractors who do the work, and a few consultants who do it a lot. All the contractors have their own proprietary equipment and methods. If by "parameters" you mean cement content, column diameters, etc., the answer is particular to the soils in question and the contractor's tools. Test sections prior to bidding or prior to production grouting are common and very helpful, and for a small dam, the cost of test sections, equipment mobilization, quality assurance-quality control, and other startup tasks could make JG less attractive.
Remember that for a dam's stability, you may need the jet grout to provide lateral resistance in addition to bearing capacity, which requires high strength on horizontal surfaces under the slopes. Therefore, any continuous weak horizontal layers could be a problem for a dam, even if they are not such a big deal for other structures that just need bearing capacity or control of settlement. This is not as easy to accomplish. You may also need good column overlap to be able to mobilize the lateral resistance (complementary shear on vertical surfaces).
Use Google etc. to search for papers on jet grouting at Tuttle Creek Dam, Kansas, and Wickiup Dam, Oregon, which were modified for earthquake problems.