Green buildup on concrete...fertilizer???

[Aaron Sullivan 14]

we are currently working on a tennis club property restoring two large decks. the manager, today, added the surrouding aggregate as well. we have ran into a stain that runs the length of a section and it appears to be from rain/irrigation runoff. it is green, gritty and pretty thick. hot water won't get it off at all. i am assuming it is fertilizer?! i am not totally sure, but i need to know how to remove it as they want the area sealed as well.

thanks in advance,

aaron sulllivan

alpine pressure washing

nashville, tn

[Aaron Sullivan 14]

anyone???

[One Tough Pressure 580]

How about a picture.

[Aaron Sullivan 14]

no pics as of yet, but someone must know what i am talking about.

COME ON, HELP ME!!!!!!!!

PLEASE!

[newlook 265]

Aaron - is this stain on the deck (wood?) or the concrete?

[newlook 265]

Concrete...my bad!!!

Sounds like something may have etched it. Have you thrown any chemicals at it vs. just hot water?