- Home Updated: 04/10/02 Blackburn Sampling, Inc. is the provider of the Blackburn COLIWASA COmposite LIquid WAste SAmpler and accessories. Tradeshow Announcement We will be a proud exhibitor at WEFTEC 2002, come see us at the show!!! Blackburn Sampling, Inc. is dedicated in providing a safe, cost effective sampling method for industries that follow the standards set forth by the EPA and OSHA .www.blackburnsi.com