HAVERHILL — Lawrence-Scioto Solid Waste Management District officials knew the household hazardous waste collection event Saturday would be large — after all, they started 20 minutes early because the cars were already lined up at the Dow Chemical plant entrance gates.

By the time the event was over at 1 p.m. Saturday, 322 vehicles had wound their way through the collection drop off area — slightly less than 80 cars an hour.

Not only was the car tally an increase over last year, but the tally for everything else was, too.

In 2010, the event collected 962 tires; this year 1,231 tires were loaded up to be recycled. Last year people brought 1,000 pounds of oil; this year that figure was 3,200 pounds. In 2010, 10,000 pounds of paint was collected; this year the paint total was 21,000 pounds.

“That’s more than double (last year),” Palmer said. “I think people are becoming more aware of what we’re doing. And the district is happy to provide this, free of charge and we want to encourage people to participate.”

In spite of this spring’s prescription medication takeback event, people brought 138 pounds of pills and liquid medicine. Lawrence County Sheriff Jeff Lawless said he’s pleased this medicine was disposed of safely.

“This is a great way for people to dispose of medication in a safe manner. It was incinerated yesterday. This ensures the medication didn’t end up in the wrong hands or flushed down a toilet and eventually in our waterways,” Lawless said.

Some other items and amounts collected: 44 pounds of propane tanks were collected, 45 pounds of fluorescent bulbs, 300 pounds of toxic solids, 500 pounds of flammable liquids and 5 pounds of mercury.

Of the 322 cars that participated, 190 were from Lawrence County. Of the 190 Lawrence County participants, 90 were from Ironton, 19 from Proctorville, 16 from Chesapeake, 5 from Coal Grove, 4 from Deering, 17 from Kitts Hill, 5 from Pedro, 26 from South Point, 4 from Willow Wood and 2 each from Wilgus and Waterloo.

“People keep asking me if we’re going to do this again,” Palmer said. “And the answer is yes, we are. We’re definitely having this (collection event) again next year.”