At 0710hrs, EPA was notified of a spill at the Mirant Kendall Power Plant that resulted in a sheen to the Charles River, which is in the Coast Guard zone. EPA began coordination with the USCG duty officer and responder. USCG and MADEP arrived on scene around 0830hrs and integrated into incident command. At that time, the facility notified their Oil Spill Response Organization (OSRO). As the response effort progressed, EPA continued to coordinate with those on scene.
At 1315hrs the USCG and the MADEP responders requested EPA presence for response coordination, coordination with the facility, and information regarding the status of the facility which is regulated by EPA.
OSC Lipson arrived on scene at approximately 1430hrs and integrated into the incident command system. MADEP and company officials relayed the events of the day, which consisted of deploying boom in locations around the outfall area of the facility (Charles River), cleaning the lubrication oil house where the discharge occured, recovering product and debris from the plant intake area beneath the lube oil house, checking the systems at the facility to discover the failure point, and determining the next steps to rectify the issue.
The release of oil began during a routine cleaning of a condenser. A high pressure water seal was compromised which led to system water displacing oil in one of the Bowser units, where purification of the lubrication oil takes place. This caused the tank to overflow, releasing oil and water into the lube oil house. The oil and water mixture overflowed from the structure into a catch basin which led to the plant cooling water intake. Since the intake area was operational at the time, it sucked the oil and water back through the plant and discharged it to the outfall. When the release was discovered, the system was immediately shut down and response efforts began. Due to the nature of the spill, it was difficult to determine an exact spill amount. The facility estimates the release to be between 50 gallons and 350 gallons (the maximum contents of the tank).
After the oil which had affected the Broad Canal and the Charles River was contained, recovery efforts began at the intake area. Approximately 2200 gallons of oily water and debris was collected via vacuum truck. The facility also had their contractor patrolling the Charles River in their response boat. They were tasked with performing recovery via absorbent booms and pads where a sheen was evident and checking for additional effected areas along the shoreline.
EPA, MADEP, and USCG all issued the Responsible Party Notice's of Responsibility which the facility accepted.
Unified Command decided that there would be no further response efforts during the night and that operations would resume in the morning.
OSC Lipson reported back to the facility on Monday, November 23 at 0800hrs and attended an incident briefing. It was decided that prior to flushing the system through to the outfall, all efforts would be made to recover as much residual oil as possible. Internal pumps were used to move water back to the intake screens where any visible sheens were captured and contractor personnel made confined space entries into interior plant manholes to mop up any residual found there. A staged start-up procedure was then developed, approved by the involved agencies, and scheduled to begin the following morning.
On November 24, after the outfall was sufficiently boomed, the circulating pumps were slowly brought up to speed one at a time to flush out any remaining oil in the system. As expected, sheening was seen within the hard and absorbent boom, but nothing was seen beyond the boom. By the end of the day, all of the pumps were operating at 100%.
On November 25, the circulating pumps and steam turbines were all restarted and the effluent continuously monitored. Approval was given by MADEP and USCG for the outfall boom to be removed on December 2, 2009.
