APRIL 27, 2015
TOMALES BAY, CALIFORNIA
Caltrans crews worked Sunday to clean up roughly 6,000
gallons of milk and 100 gallons of diesel fuel that spilled near Tomales Bay earlier
in the day, according to the California Highway Patrol and Marin County fire
officials.
Both directions of state Highway 1 were closed as of around
5:30 p.m. so Caltrans crews could assess the scene, CHP Officer Damian Cistaro
said.
Officers responded to a report of an overturned tanker on
state Highway 1 roughly a mile north of Nick’s Cove around 11:45 a.m., CHP
Officer Andrew Barclay said.
Barclay said 6,000 gallons of the big-rig’s roughly
10,000-gallon tank spilled into the street, while the rest remained in the
tanker.
The driver of the truck suffered minor injuries and was
transported to the hospital, according to officials with the Marin County Fire
Department.
Fire officials said the truck, which was heading south near
Nick’s Cove, failed to negotiate a turn and landed on its side along the
highway. Firefighters were able to use absorbent materials to sop up the
spilled milk and diesel fuel.
Crews were monitoring the spill to ensure it does not
threaten bay waters, fire officials said.
A Sig-alert was issued around 1:10 p.m. for both directions
of Highway 1 and was lifted around 1:45 p.m. before authorities closed the
highway again for Caltrans crews, Cistaro said.
As of around 5:30 p.m., Cistaro said the roadway was
expected to be closed for one hour.
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THE ROLLOVER RISKS OF TRUCKS:
FAILURE TO NEGOTIATE A TURN, EVEN SMALL
OVERCORRECTIONS CAN RESULT IN ROLLOVERS.
We have written many times before about the rollover risks
of trucks. Here is of the earlier blogs.
Dynamic Stability of a Vehicle Carrying Bulk Liquid and
Driving Over a Bump or Negotiating a Turn
The forces generated by the sloshing of bulk liquid carried
in tanker trucks can cause accidents.
The roll-over tendency of a vehicle can be measured in terms of how many
"g" (gravitational acceleration) that vehicle can withstand in
cornering.
The higher this value, the
safer the vehicle. For example, full
size passenger cars can withstand around 1.2 g.
For a loaded semi-truck the number is 0.4, and for half empty tanker
truck it can be as low as 0.15.
Tanker
trucks are used for transporting milk, water and a number of liquid fuels. The trucks sometimes need to operate on rough
terrain at relatively high speeds. This
exposes the truck to a roll-over risk. If the tanker is partially empty, the
risk of roll-over becomes much higher.
//-------------------////
THE ROLLOVER RISKS OF TWO-TANK TANKERS ARE TOO GREAT TO
CONTINUE TO ALLOW THEM CARRYING HAZARDOUS MATERIALS WITHOUT ADDITIONAL SAFETY
MEASURES
The recent rollover of a two-car tanker in Los
Angeles reminds how dangerous these two-tank tankers are for carrying flammable
liquids.
The fluid slosh can definitely throw you around if
you're not expecting it. You have to be smooth with your inputs. If the
driver was being stupid/distracted/whatever he could have easily steered/braked
too quickly and caused the slosh to tip him over.
Tankers are actually the hardest commercial vehicle to
control. Any tanker that has to be completely cleaned out between loads
cannot have baffles. Imagine the kind of things that would grow in a tanker
full of milk if you could never wash it out. There are also still older tankers
out there that move things such as fuel that have baffles today, but did not
always have them in the past.
No question its the driver's fault, but he really could have had some surging
that contributed to the incident.
