Green’s Dictionary of Slang

(US campus) very.

1989		P. Munro Sl. U. 106: You’re still studying at this hour? It’s hecka late.
2002		Teen Lingo: The Source for Youth Ministry 🌐 hecka adv. used in conjunction with another word as an intensifier. Examples include: hecka-cool, hecka-stupid, hecka-crazy, or hecka-funny.