Year of release:
The movie is based on the manga "Kuroi Ame ni Utarete" by Keiji Nakazawa, published in 1967. It's a work about the atomic bomb catastrophe in Hiroshima in 1945 and the aftermath. This is the second anime Kitaro wrote the music for.
The anime is available in Japan only. The DVD is in Japanese without subtitles. So it's not easy to understand the storyline. The music is based on the typical Kitaro sound of 1984. Interesting: the last piece is played by Kitaro together with a Japanese female singer. It seems that a soundtrack was never released. Very often the music is just background music and disturbed by noises in the movie.