coolant leak, water pump maybe?

[fiveohpatrol]

i've just noticed a small amount of coolant on my garage floor so i have a leak somewhere, i dont think its a big leak but i wanna find it anyway cause i can't stand seeing my car bleed any color when i jacked my car up i noticed theres quite a bit of coolant mostly on the underside of the lower radiator and some more around that area, so i started the engine to see if i could see the leak but it wouldnt do it, maybe it only leaks when i get back from runnin it pretty hard, anyway when i was underneath it looking for a leak i saw white smoke coming off the top of the waterpump, could the pump be causing the leak? is there a valve in the pump that opens when the pump goes bad? how much does a replacement pump cost? i think i may replace mine sooner or later because it looks like its original and will probably go out soon if it isnt already i dont know much about cooling systems and need some help, thanks everyone

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88 Notchback 5.0, 3.73's, pulleys, BBK headers, off-road H-pipe, flowmasters, subframe connectors, 65mm TB, shift kit, March ram air kit, motorsport wires, MSD coil, upper and lower control arms, 155lph fuel pump, cheap 2800 stall, Crane Adj.FPR, best time- 13.99@99.75, not yet tested times after 1.7RR install