How to control salt water brine as an ingredient?

So, this is a curly one and I'd appreciate your help.

Beverage manufacturing (non-carbonated, non-alcoholic); we mainly produce juices and sports drinks.

We have a (potential) customer that has access to an underground salt/mineral aquifer/lake. Currently he pumps this salt water/brine up from about 40mtr underground and uses it for a variety of personal care products such as hand creams and lotions. He has now decided to branch out into beverages - which for us as a company would mean adding some of his salt water to our sports drinks, and marketing it as an electrolyte/mineral replenishment style drink. 

The qualification of electrolyte (or not) is something I can manage, but I am at an absolute loss on how we are even going to control this salt water as an ingredient.

The process is as basic as a pipe in the ground on a farm property from which the water gets pumped up, no further processing, just straight into an IBC. How can we guarantee that there is no contamination from pesticides from surrounding farmland or contamination from animal feaces through groundwater? How do we ensure that salt and mineral content is consistent? Customer has no food safety program in place, no controls etc. Other than testing each and every batch that is pumped up for not just the 15 minerals he claims, but also for a very wide range of contaminants will be a lengthy and very costly exercise.

Personally, I think the risk here is too great to proceed, but would be interested on hearing your opinions.

In a different way we had a similar situation with a customer that just discovered a natural spring and wanted our client to accept tankers of it for their beverages.

What our client did was require them to go thru the approved supplier program which of course requires a full blown food safety program. Etc etc.

They will never qualify unless they remake their entire operation into a commercial enterprise.

This is what our client did and their customer did not qualify and continued to stay a customer of our client to this day... I think they also got more respect for our client as well from a safeguarding standpoint. 

Thanks Glenn, I will take exactly that route.

I tend to overthink sometimes - this is really the most basic (and likely most effective) solution to my problem and it's been staring me in the face all along.

Most excellent, yeah, simply solutions are always great!

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The process is as basic as a pipe in the ground on a farm property from which the water gets pumped up, no further processing, just straight into an IBC. How can we guarantee that there is no contamination from pesticides from surrounding farmland or contamination from animal feaces through groundwater? How do we ensure that salt and mineral content is consistent? Customer has no food safety program in place, no controls etc. Other than testing each and every batch that is pumped up for not just the 15 minerals he claims, but also for a very wide range of contaminants will be a lengthy and very costly exercise.

 

Personally, I think the risk here is too great to proceed, but would be interested on hearing your opinions.

The risk is high, and the testing is necessary.  Perhaps after some number of batches or test results you can reevaluate the level of risk and reduce testing, but it is all necessary in the beginning.