On the link above you find the common answers.
To use limestone is no problem. And I can not see any problem with using limestone from industrial production if it free from any kind of poison. Which depends what kind of process it has gone through. But of course Dolomit or natural limestone is to prefer.
Copper sulphate is poison used towards fungus. I will say it is not correct to use that in ecological farming.
It is better to use natural anti-fungu like:
Plants and other organisms have a chemical defense
gives them an edge against microorganisms such as fungi.
Some of these chemical compounds can be used as
Tea tree oil 
Cinnamon Oil (essential oil) 
Milk  
Ampelomyces quisqualis AQ10, CNCM I-807  
Some live or dead organisms, can be used for
to effectively kill or inhibit fungi, and thus
used as a fungicide:
The bacterium Bacillus subtilis
Kelp (dried and powdered kelp is fed to livestock for
to protect them from fungus in the grass)
But if the grapes or vegetables will be attacked by fungus or insects or whatever. The soil is bad, the enviromental situation is bad. It is to much mon-culture etc. Something is wrong. It is ok if some procents of the vegetables are attacked and destroyed. That is a kind of harmony. But if it is too much destruction - you have made some wrong. And it can be many things.
Many "ecological" farmers think chemical. That is also total wrong. Look instead at nature. There is balance and harmony.
Som ecolgical rules are not correct. You are allowed to castrate bulls and take away their horns in ecological farming. That should be forbidden. A bull has not much life than to be just a bull. And if you must take away the horns because they can hurt you - lokk for another job. I do not know if the Bordeaux-mix is allowed in ecological farming. If so - the rule is wrong.
Farming can be excological or not ecological. Not 95% ecological.