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Now the existing impact to the Madison Aquifer, a major aquifer for not only the Black Hills but a larger multi-state area, are measurements showing it down in some test sites as much as 60-feet, he said.
Some test sites show less impact for the Madison such as a test well near the Wyoming-South Dakota state line in the Black Hills National Forest, he said.
Up against the '89 drought, the current impacts are about two-thirds as severe, said Driscoll. The USGS will continue to monitor the drought, which is not showing any certain signs of abating, to determine on-going impacts to the Madison and other aquifers such as the Minnelusa and Minnekahta, said Driscoll.
On another matter, both Driscoll and co-worker Larry Putnam held a brief discussion with Lawrence County Commisssionres Tuesday of some of the results of dye injection into areas near Spearfish Creek's "loss zone."
In this loss zone, the creek waters go underground and enter a complex system of water travel still being figured out through testing by the USGS and partners Lawrence County and Spearfish.
In one test, the dye showed up in a well in Mountain Plains II subdivision in the extremely fast time of only six days, said Putnam.
The USGS and Lawrence County in partnership with Spearfish have spent approximately three years doing an aquifer vulnerability study of a great deal of Lawrence County. The results of that study were given to the county and Spearfish approximately two years ago, said Driscoll.
One of the many uses of the study was to help planners and policy makers avoid development in areas where aquifers are most vulnerable. In one case there is a large area of rock outcropping that is a massive re-charge area for the Madison Aquifer.
Besides industrial contaminants, one of the areas of concern is the impact of large numbers of septic tanks and the contamination factors they can bring in greater concentrations.
At present, Driscoll and Putnam are seeking continued funding for a partnership project between Lawrence County, Spearfish and the USGS. The county and Spearfish would each contribute $25,000 which is matched dollar for dollar by the USGS.
There is also funding needed to continue monitoring stream gauges at three places with one of the most important being on Crow Creek, said Driscoll.
The Crow Creek water system is extremely complex and very, very large, said Driscoll. Impacts from any changes to the system having repercussions not only all over the county but out into other counties and even states, said Putnam.
While the County Commission made no formal approval move with the USGS at Tuesday's meeting, it is likely the issue will come up for official funding allocation action at a meeting of the board in the near future.
