Rover to the rescue
One of our technicians called me out one day for assistance. He had been on the job site for several hours with a trailer jetter and could not clear a commercial drain stoppage. It was a strip mall with seven food establishments and they were all flooding from their floor sinks and floor drains. These were all heavy grease users: a fried chicken take-out, a pizzeria, a donut shop, a Chinese restaurant, a bread bakery, and two more large eateries. Everyone was panicking because they had to close their businesses and they were losing money. The owner of the mall was there too. He was getting frustrated and anxious — he wasn't seeing any progress. I jumped in as the rover and went to work.

This was a long sewer line without any clean outs close to the stoppage. The jetter would bind almost 300 ft. downstream. Old grease in a restaurant sewer looks like hard cheese. It can be as hard-as-a-rock and can impact itself over long lengths of pipe. This grease was very hard and too much for our jetter to break through. Every time we pulled the jetter hose out of the pipe, the hose was covered with old, smelly grease. I advised the owner that we would need to locate the stoppage and cut the pipe; I knew it would be deep. The owner was reluctant but I took the "expert" posture and the job was approved. We strapped our locating transmitter to the jetter hose with several tightly wound layers of electrical tape, about three feet behind the jetter-head and allowed our jetter to pull the transmitter to the sticking point. I located the pipe to be 8 ft. deep under a heavily traveled, six-lane boulevard and it was rush-hour. This was a $10,000 repair, just for openers.

The backhoe and my crew were digging within 2 hours. A pumper was called to take the greasy water as soon as we cut the line. After several feet of the pipe was exposed, the backhoe driver scooped out a pot-hole on both sides of the pipe, deep inside the trench directly alongside the spot we wanted to make our first cut to purge the system. The narrow partition of dirt between these adjacent holes, (the dirt directly below the pipe the backhoe can't get) was knocked down with shovels, creating a larger, singular catch basin below the sewer. The makeshift basin was then lined with plastic drop cloths.

The pumper positioned his hose into the now, protected basin we created and stood ready. We snapped — the water rushed out — and he pumped; all in one choreographed motion. Hundreds of gallons of greasy water were collected safely, leaving us a clean trench to work in. We would always take precautions to prevent a trench from filling with greasy water.

Grease in a trench is not only putrid smelling; it is also a chemically hazardous condition. Inspectors don't like to see evidence of grease in a trench — it becomes an environmental issue. Any contaminated soil you encounter or create, whether it's under the street or under a restaurant kitchen during a repair; is treated as hazardous-waste material and disposed of accordingly, like an oil spill. You can't put it back in the trench for back-fill. When that happens, use sand to make up the missing volume needed. Sand is selfcompacting and packs itself into soil fissures and voids.