Lots of blue liquid leaking from underneath the car

[emc2]

I discovered a huge pool of blue liquid underneath my car about 1/3 of the way from the rear and perhaps a bit to the right of centre. I took it in to the mechanic a week later (unfortunately he was on vacation last week). He was not able to find any leaks and showed me that the entire undercarriage of the car was dry. He said it could not have been windshield washer fluid as that line does not run underneath the car, but runs internally through the car. Also, the anti-freeze in my car is orangey pink so it could not have been that either. I drove through some rain storms the past couple of days so maybe that is why the undercarriage was dry and he could not locate the leak? When I sweeped the liquid away with a broom I noticed that it pooled into droplets above the dirt instead of soaking into the dirt like water. Also, it has left a large stain in the floor of my garage (sort of like oil) and not completely dried out even though it's been a week since the leak was discovered.
Has anyone had this experience before? I wonder what this liquid could possibly be and where it is leaking from.

 

[cidsamuth]

"1/3 of the way from the rear." The only fluid lines running from the rear are brake fluid and fuel. You'd smell it if it was fuel, so check your brake fluid level.

 

[SteveS]

Although in the US I would say that there is no blue fluid in the car except windshield washer fluid, in Canada blue brake fluid is a thing. I'd be really checking for brake fluid before driving the car at all.

 

[M-Sport fan]

They can still buy the Ate Super Blue Racing DOT4 brake fluid up in the northlands??

(But yes, it could be old fluid changed over to the Ate stuff long before it was totally banned here south of the border.)