The following video is brought to you courtesy of the Sky News YouTube Channel. Click the video below to watch it now.
Sky News has investigated just how corrosive these pits are – and why nothing is being done about them.
SUBSCRIBE to our YouTube channel for more videos: http://www.youtube.com/skynews
Follow us on Twitter: https://twitter.com/skynews and https://twitter.com/skynewsbreak
Like us on Facebook: https://www.facebook.com/skynews
Follow us on Instagram: https://www.instagram.com/skynews
Sky News videos are now available in Spanish here/Los video de Sky News están disponibles en español aquí https://www.youtube.com/channel/skynewsespanol
For more content go to http://news.sky.com and download our apps: