Thousands of dollars for disintegrating driveways -- all over our area. The question: Whose fault is it? Our Call 4 Action volunteers first brought this story to the I-Team: customers and contractors who say a big concrete company didn't give them what they paid for. Over the years, Sussex contractor Jim Mukerheide has poured more concrete driveways than he can count, but the number now falling apart is adding up. "[This] is a perfect example, where it's just turning to powder," Mukerheide complained at one job site. "There's nothing left of the top. It just comes right off." Crumbling. Cracking. Scaling. The driveway Mukerheide poured for his neighbor, James Moran, looks like the surface of the moon after just a couple years. Moran paid $9,200 for it. "Look at it," Moran exclaimed. "This is embarrassing for gosh sakes, people come over, what the heck? What's going on?" It's something Mukerheide wanted to know, too, because the same thing is happening to at least a half-dozen other driveways he put in back in 2006 and 2007 -- no problems before or since. "Every day I walk over here it makes me sick," said Mukerheide. "If I look at my driveway, and I look at the driveway I poured down the road in 2005, they're fine. There's not a mark on them." That's when Mukerheide started to question the quality of the concrete itself. It came from Milwaukee's Central Ready Mixed. They're taking no responsibility," said Mukerheide. Convinced his work wasn't the problem, Mukerheide drilled out core samples from some of the bad driveways, and paid a lab in Texas thousands of dollars to test them. "I am a responsible contractor that is taking notice," Mukerheide said. "I don't want my customers out there going through this. I mean, this is just wrong. This is not the way concrete's supposed to be." It sure isn't. The I-Team obtained invoices from Central that show Mukerheide ordered what's called a six bag mix -- six bags of Portland cement in every cubic yard of concrete. The lab found the concrete Mukerheide bought from Central and poured in James Moran's driveway only had about four-and-a half bags. "Lab tests don't lie," said Al Rusch, a long-time masonry instructor with Waukesha County Technical College. Rusch reviewed the lab reports and said Mukerheide didn't get what he ordered, which he feels may have caused the driveways to crumble. Reporter: "What was the first red flag you noticed? Rusch: "Strength. Strength of concrete went down." In addition to being light on Portland, the lab also found Central's concrete "lacked proper air-entrainment." Air-entrained concrete has been treated with a chemical that, when it sets, creates millions and millions of tiny air bubbles. Those air bubbles protect concrete poured outdoors from freezing and thawing. Concrete without proper air-entrainment can result in scaling and cracking. "The amount of air-entrained additive that should have went into this concrete didn't look like it was there at all," explained Rusch That's why James Moran now wants Central, not Mukerheide, to pay for a new driveway. Vince Cochran does, too. The lab found the core Mukerheide pulled out of his disintegrating driveway "appears to have been contaminated by diesel oil from the machinery used in making the concrete" and "there was no entrained air noted in the concrete." Tests also showed the concrete had nearly as many fillers as it did actual cement -- again, not what he paid for. "We put our trust in them to give us the material we ordered," said Mukerheide. The only way to really fix the driveways is for Mukerheide to rip them all out and start over. "I appreciate his integrity," said Cochran. "He's been standing by his work, and he's willing to do what it takes, but that's out of his pocket then." And Mukerheide can't afford rip out and replace every driveway he poured over those couple years. "All my customers, I feel bad for them," admitted Mukerheide. "They spent all their hard-earned money, especially these times right now, this is what they got in then end, is they got concrete that looks like it's 50 years old." Mukerheide isn't the only one who has a beef with Central Ready Mixed. A Pewaukee-based contractor recently filed a lawsuit claiming breach of contract and negligence. We tried, but no one from Central would talk to us about any of this, after their lawyer told them not to. In the end, we have no idea how many more customers got bad driveways, but the I-Team spoke to several other contractors who all feel the same way -- they got bad concrete.