By Leonard Rydell
Riverbend Landfill is out of control, and the Oregon
Department of Environmental Quality (DEQ) is determined to ensure that, at any cost,
the dump continues to grow. This is not right. Let me explain.
I am a consulting Civil Engineer, Professional Land Surveyor,
and Water Rights Examiner licensed in the State of Oregon, and this year am
celebrating my 40th year of professional practice. I have been following
Riverbend Landfill since 1982 when I laid out the original survey coordinate
system for Riverbend, revised the original construction plans, and -- for a
brief while -- was the Engineer of Record until my concerns
over Riverbend Landfill's failure to meet
the landfill's design and specifications led me to resign.
It was obvious to me even then that Riverbend Landfill was
going to become a major environmental hazard and that the DEQ would be no
help. I laid out Cells 1, 2 and 3. When I measured ground water levels, I learned that ground water would move in and out of garbage placed in those cells. Despite rules that required 95% compaction, DEQ allowed garbage to be placed below ground
water levels in those cells when DEQ's own tests showed compaction
of cell bottoms to be no more than 60% during the first four years.
The original design was for the landfill to rise to a height
of 157 feet above sea level, ie, 7 feet above the surrounding farm fields and Highway
18. After the original Yamhill County and DEQ approvals, I was asked
to revise the plans to steepen the slopes so that the dump could rise 28 feet
above the top of the farm fields on the uplands.
In the 1980's, earthquakes were not even discussed as part of
an engineering design. None of the original 8 cells of Riverbend Landfill
have ever been studied to determine whether they will withstand a major
earthquake (7.5 or larger), yet the DEQ continues to allow garbage to be
added to the landfill, now piled up to 135 feet above surrounding farm fields (yes, that is a 108 foot increase
from 1982).
Cells 4 and 5 have been studied to a 7.25 magnitude
earthquake. A 9.0 magnitude earthquake like the Big One we are expecting is
56.234 times stronger than a 7.25 earthquake but releases 421.696 times the
energy. It is not the same as paying $9.00 for lunch instead of $7.25.
But wait, there is more! The July 1993 study for Cells
4 and 5 for a 7.25 earthquake was based on landfill slopes of 4 feet horizontal
to one foot vertical, yet the DEQ is allowing a steeper 3.5 feet
horizontal to one foot vertical slope and a maximum height 46 feet higher than
that approved by the 1993 study. Recently I asked the DEQ permit engineer when the increase in
height was approved and what the design calculations were. His reply was that a 3.5 foot horizontal to one foot vertical slope is "allowed by administrative rule."
To me, that is like adding four floors to a skyscraper without requiring engineering
calculations because the additional height is allowed under the zoning code.
My concern about the earthquake stability of the landfill
should also be your concern. The 20 July
2015 New Yorker Magazine contains an excellent article about the Cascadia
Subduction Zone Earthquake, the Northwest's "Big One." See http://www.newyorker.com/magazine/2015/07/20/the-really-big-one.
As Kenneth Murphy, FEMA’s Region X (Oregon, Washington,
Idaho, and Alaska) Director says, "Our operating assumption is that
everything west of Interstate 5 will be toast."
DOGAMI's Yumi Wang points out that we must also worry about soil liquefaction. In her
Hospital Report for Yamhill and Lincoln Counties, she says, "In addition to damage to bridges from earthquake shaking, damage would
occur from tsunami flooding to road segments in low lying portions of Highway
101 especially near the Siletz River, from landslides especially toward the
western portion of Highway 18 (ODOT mileposts 13 to 18); and from liquefaction
especially between Sheridan and McMinnville." In case you don't
know, Riverbend Landfill is located on the river side of Highway 18 between
Sheridan and McMinnville.
Look for my next article on water and the dump.
