This movie was made by a high school, and not a rich one at that. Ayer High School in Milpitas, CA made this movie. At that time, Milpitas was a small suburb of San Jose. The movie was actually a big deal for the town and many had a blast making it, being extras and then watching it in our little theater.
Sure, as a movie, it's nothing great. But it was made for practically nothing by high school kids equipment that was not very modern at the time.
Ecology as it was known was just becoming a big thing back then, and this movie is about a monster spawned from pollution.