ALLWASTE <ALWS.O> TO ACQUIRE FIRM Allwaste Inc said it entered into an agreement in principle to buy Tank Cleaning Co, a privately-held company that cleans tank trailers, in exchange for about 1.3 mln shares or Allwaste common. Allwaste said that Tank Cleaning earned about one mln dlrs before taxes last year and had about 1.5 mln dlrs in pre-tax income for the nine months ended September 30.