NC0085359_Occurrence Summary_20170307

Sludge Spill at 12 -Mile WRF on 3/7/18 to 3/8/18
On 3/7/18 a sludge spill was found by the night shift operators at 11:45. Following is a summary of
the occurrence.
3/7/18 at 23:45 — Found sludge from the South West Digester running in the road toward the storm
drains. A line out of the out decant pipe that had been used for sampling was broken. It is located
about 10' above the ground near the construction that is under way for the new solids handling building
in a dark area of the plant. It appears that the sludge had been spilling for quite a while.
Patrick Moore and Tim Harrell looked for a ladder to stop the sludge from running and out of the
digester. The only ladder that they saw was in the keep stock cage under lock. They also tried to start
the tractor, but it was not working. Without a way to get to the broken sampling line out of the
digester, they called Jonathan Jordan plant supervisor.
3/8/18 at 00:15 —Jonathan received a call about the solids from the operations staff. He asked them to
stop the flow immediately. They told him they had tried to use the tractor and also looked for a ladder
to reach the broken pipe and that the solids were about to reach a storm drain. Jonathan told them to
stop the flow to the storm drain with whatever they could find and that he would be at the plant as
soon as possible.
3/8/18 at 01:00 —Jonathan arrived at the plant. The operators had put plastic around the storm drains
where the contractor had already placed gravel and block. Jonathan cut the lock on the keep stock
cage, removed the ladder, put on a Tyvex suit to protect himself and told Patrick and Tim to follow him
to the broken line with as many rags from the rag barrel as they could carry and a roll of Duct Tape. He
was able to shove rags into the broken pipe and then tape the pipe closed so that the rags could not pop
back out of the pipe.
3/8/18 at 02:04 —Jonathan called me and let me know what had happened. He asked me about using a
contractor's back hoe to dam up the flow. I told him to go ahead if he could find one to use and that I
would be there as soon as possible.
3/8/18 at 02:45 — I arrived. At this time, Jonathan had placed a dirt dam across the road to prevent any
more sludge from going toward the street. He had also added dirt over the plastic the operators had
placed on the storm drains to prevent solids from going into them. At that time everything that could
be completed to contain the spill was done.
3/8/18 at 05:30 — Contractor from Adams Robinson is on-site. I went to their office to let them know
about the spill that was adjacent to as area they were working at and to let them know about using their
back hoe. The contractor asked if there was anything they could do to assist with containing the spill.

They sent out a back hoe after reviewing the plans and dug a hole in the low area of the spill so that the
solids would collect in that area.
3/8/18 at 07:00 — I called Josh Brooks and asked him if it was possible to get a Vac Truck to clean up the
spilled solids. He was going to contact field ops to let them know about the issue.
3/8/18 at 07:15 — I called Bart Farmer to let him know about the incident and what had been completed
at that time.
3/8/18 at 07:30 — Ron Wallace from Charlotte Water Maintenance was on-site. The pipe that was
broken was the same pipe that he had repaired 3 years ago when it ruptured. He had placed a copper
shark bite valve on the pipe. It was no longer in place. Ron purchased another shark bite valve and with
the assistance of the contractor's crane operator was able to be lifted into place to seal the pipe with
the new valve. At that time we could not find the valve that had been on the pipe.
3/8/18 at 07:45 — Bart Farmer was on-site to see the extent of the spill.
3/8/18 at 08:05 — I called Roberto Scherer with NC-DWR to let them know about the spill and that it was
contained. I also sent him a picture of the break in an email at 09:45. Bart Farmer was copied.
3/8/18 at 08:15 — UCPW on-site with a VAC truck. The spill was cleaned up by starting from the furthest
point and then moving back to the site of the broken pipe that caused the spill. UCPW was on-site until
20:00 on 3/8/18. A second VAC truck was used for about an hour to assist the first truck for about an
hour.
3/9/18 at 09:00 — The spill had been cleaned up to a large extent with the road scrubbed clean and the
only remaining sludge pooling in a small area around the digester. Jonathan and I had both left the
plant the previous day by noon. At this time we started looking for the missing valve. It was found and
brought back to the plant and cleaned. It appears that some of the teeth in the valve had broken off,
and this caused the valve to pop off the pipe resulting in the spill. I have asked Ron Wallace to contact
the manufacturer and determine the anticipated life of this type of valve in a wastewater application.
This is a $30.00 part.
3/9/18 at 13:00 — Daniel Mosely and Wyatt Howell went to Olde Sycamore WRF to pick up several 50
pound bags of sodium bicarbonate (baking soda). This was placed around the southwest digester to
reduce the odor. Sludge at 12 -Mile WRF is high in nitrogen, adding lime would off -gas a horrendous
odor (for a short amount of time) so we chose to use the bi-carb to keep odors down.
Dawn K. Padgett, Operations Manager — Charlotte Water, UC O&M Contract