Bulgarian municipality of Oryahovo said it has opened 7.5 mln levs ($4.5 million/3.8 million euro) tender for construction of a pre-treatment waste plant and a composting facility for sorted waste.The pre-treatment waste plant will have a capacity of 15,300 tonnes and composting plant's capacity will amount to 4,500 tonnes, the municipality said in a statement on Saturday.The works on the project should be completed in 660 days.Offers should be submitted by August 31.(1 euro = 1.95583 levs)