All of Dr. Brenda Bowen's core samples were drilled in fall of 2016. It should also be noted that NOT A SINGLE ONE was drilled on the south side of I-80, so much for any kind of full scientific study of salt inside a valid control volume! Pretty hard to have an inventory of the salt if the primary consumer has relocated a very large percentage of it outside the study area. It may be that the only real study required to determine where all of this salt is going is to look to the south at those tall white piles of granular material.
It is interesting that BLM and Intrepid Potash folks all claim "mass balance" with the return of either 550,000 or 600,000 tons of "waste salt". BLM has advertised the 600,000 figure, Intrepid officially claimed the 550,000 in the Speedweek program, allegedly these figures come from the same instrumentation that records salinity and water flow in the return ditch. I'll leave it to you to decide if either figure makes sense based on physical observation of the track surfaces.
In terms of "mass balance" the BLM uses the claimed mineral removal amount as compared to the returned tonnage. In recent years the Intrepid mineral extraction process has moved away from the traditional surface brine pumped away in collection ditches to deep wells drilled on Intrepid property south of I-80. These mineral quantities are pulled through private property and are not subject to BLM monitoring or royalty payments. Hence the BLM statements that return salt tonnage has exceeded removal. It should be pretty obvious to anyone that has poured any quantity of water onto the salt flats that the dense cemented halite surface dissolves in the water, and that this brine then percolates into the layers below the salt. The current Intrepid wells are then able to recover the brine from the porous sponge like depths below the salt, generating a subsurface flow to the south carrying the minerals to the evaporation basins without lease terms being applied. The various surface barriers have little impact on surface brine when it can flow freely under I-80, Central Pacific Rail, and Highway 40 carrying the minerals dissolved in the water. The water levels and operation of the Intrepid evaporation ponds effectively shelters them from mineral removal by the natural rainfall and surface water coming in from adjacent mountain ranges. The race track surfaces north of I-80 have received large rainfall over the past few years, including huge amounts of collected water flow off the Silver Island Mountains and areas north of the salt flats. All of this water flow onto the salt has increased the amount of dissolved minerals available in the subsurface aquifers, which clearly reduces the available salt to form a usable racing surface.
There were numerous comments from racers this summer suggesting that the salt will get better if left alone. There are two major fallacies in this statement that we should recognize. First is the assumption that there is some natural process that will bring the salt back over time. This is not the case as there is no natural cycle that will move salt from the evaporation ponds south of I-80 back to the race track surface. The only way this salt movement is going to happen is if some industrial scale process like the one operated by Kaiser, Riley, and Intrepid have operated for the last 50 years is implemented. This condition has been created by man made activities, and it will only be corrected by man made actions. Second is the assumption that land speed racing is contributing any significant damage to the salt surface. The amount of salt transported off the surface by our vehicles and shoes is minuscule in comparison to the massive quantities consumed by the mineral leases.
Study the chemical composition of the base minerals in the Bonneville basin, understand the sales quantities leaving the Wendover plant, and make your own comparison to see what "mass balance" is being achieved. I think you will find the return tonnages are small fractions of what is being removed to support the potash and magnesium chloride refining and sales.
