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Thu, Aug 06, 2009 01:52 AM
Mold Pervades School Report
by Paul C. Clark Staff Writer
write the author
July 30, 2009
Mold is back on the table as a possible culprit in the
Oak Ridge Elementary School health mystery, as a federal team has found it
in several places in the supposedly mold-free school.
Guilford County Schools announced on July 23 that Oak
Ridge will not open on August 25, and that the school's students will be
sent to Oak Ridge Military Academy (grades two through five), Colfax
Elementary School (kindergarten and first grade) and E.P. Pearce
Elementary School (pre-kindergarten), at an estimated cost of $222,000.
The school system hopes to remediate any problems found at Oak Ridge
Elementary School by the end of October.
Much of the focus of the four-year Oak Ridge Elementary
School saga has been on mold, which was found at the school as early as
May 2005, three months before the official opening of the completely
rebuilt school, and as late as May 2009. Students and teachers at the
school have reported a slew of health symptoms, including headaches,
fatigue, difficulty concentrating, respiratory problems and nosebleeds.
That focus shifted in recent months for two reasons:
the Guilford County Department of Public Health on June 25 released the
final results of its epidemiological study of the symptoms, discounting
mold as a cause of any current symptoms, and recent air-quality tests at
the school found no high mold levels.
That didn't mean Oak Ridge Elementary School hasn't had
a mold problem – mold has been found at the school repeatedly, by Guilford
County Schools employees and outside experts brought in to do tests. But
health department and school officials alike thought the mold problem at
the school had been fixed, and any remaining symptoms were probably caused
by a badly calibrated heating, ventilation and air-conditioning (HVAC)
system that wasn't providing enough fresh air.
The arrival in Guilford County of a federal team from
the National Institute for Occupational Safety and Health (NIOSH), part of
the US Centers for Disease Control and Prevention, on July 14 was intended
to bring a higher level of expertise to the Oak Ridge mystery, and also to
provide a credible independent investigation of the symptoms for parents
and teachers, some of whom felt that Guilford County Schools had
stonewalled them, particularly in the early stages of the saga, before the
symptoms were confirmed by the health department. The school system has
been very open in its recent reporting on the problem.
The NIOSH team released its first report on the
school's environmental problem on Thursday, July 23, and that report is
shot through with mold. The report also lends credence to reports by
people in the Oak Ridge community that there were systemic construction
problems when the school was rebuilt in 2005, and that those problems have
made the school leak-prone, which has contributed to the mold.
The NIOSH team, which spent three days at the school,
consists of at least four NIOSH officials – including Jean Cox-Ganser, an
epidemiologist in NIOSH's Division of Respiratory Disease Studies and an
expert on building contamination; Rachel Bailey, a NIOSH medical officer;
and industrial hygienist Ju-Hyeong Park. It also included Stephen
Caulfield, a senior vice president of the Turner Group, a New
England-based firm that tests and evaluates buildings with suspected
environmental contamination; and Fred McKnight, a mechanical engineer and
industrial hygienist for the same firm. The Turner Group was recommended
to Guilford County Schools by NIOSH.
The team's first report is very preliminary, and
consists of an assessment by Cox-Ganser, Bailey and Park and a more
detailed building analysis by the Turner Group. The team left monitoring
equipment at Oak Ridge Elementary School, and may take up to two months to
issue its final report.
The first thing you notice about the report is that,
for a school that has been repeatedly cleaned of mold and has tested
mold-free, Oak Ridge seems to have a lot of mold.
Cox-Ganser, Bailey and Park noted a "strong, musty,
moldy odor" in the basement and crawl space under the school's library,
and lime on the floor of the crawl space, which is usually a sign of water
intrusion. They also noted a musty smell in the corridor around the
library, and in particular around the school museum.
Since the start of the Oak Ridge environmental problem,
Guilford County Board of Education member Darlene Garrett has suggested
that the air handlers in the HVAC system are contaminated with mold and
may be contributing to the symptoms. The preliminary NIOSH report backs up
Garrett's contention.
"From our initial inspection, it is possible that some
of the coils for the HVAC air handlers may have mold contamination," the
NIOSH team wrote. "As further discussed by the Turner Group, these issues
will have to be addressed."
The Turner Group's report was more specific, saying
that the dirt-floor crawl space under the old wing of the building is a
likely source of mold. The company based that finding on an inspection of
the crawl space and on reports from occupants of the school.
The Turner Group recommended that a flexible vapor
barrier be constructed to seal off the crawl space, and that the crawl
space itself be depressurized.
Another thread throughout the NIOSH and Turner Group
reports is that Oak Ridge has pressure problems. Modern buildings are
designed with the air pressure in specific rooms, hallways, attics and
other spaces carefully calibrated to limit or control airflow. Air flows
from areas with high air pressure, called positive pressure, to areas of
low pressure, called negative pressure. That can be a problem with
contaminated buildings, because contaminants in an area with positive
pressure can travel to areas with negative pressure.
The NIOSH team found airflow issues between rooms and
spaces. The NIOSH team said that classrooms should generally have positive
pressure compared to hallways, and bathrooms should have negative pressure
compared to outer rooms.
"This was not always the case," the team reported.
"During the day, the attic was under positive pressure in regard to the
exterior of the building. However, at night, when the dehumidifier (which
serves the classroom wings) was turned off, this resulted in the attic
being under negative pressure in regard to the outside of the building.
This allowed outside humid air to enter the attic."
If there is a mold problem at Oak Ridge Elementary
School, it's also a water problem. Mold only grows in the presence of
moisture. Another recurring theme at Oak Ridge is that the school has had
persistent low-level leaks in its roof, walls and floors. The NIOSH report
highlighted two possible causes of water getting into the school: moist
air getting into the school because of HVAC problems and direct
infiltration through the roof, walls and concrete foundation slab.
The NIOSH team reported that the foam roof on the old
section of the school had multiple damaged areas, and there did not appear
to be adequate flashing – metal sheets added to building components to
prevent water intrusion – at the junction between Room 206 and the
school's gymnasium. The team also, using an infrared camera, found
moisture in a recently repaired exterior wall next to the gym's bleachers.
The team said the roof and the flashing should be repaired.
The NIOSH team found that the inadequate flashing at
the junction of the gym wall and Room 206 was the probable cause of mold
found in the carpets in that room. The team reported that the flashing
appears to be mounted on the surface of the wall, rather than continuing
through the gym wall to prevent drainage. The team recommended that
Guilford County Schools install through-wall flashing at the junction. The
team also reported that flashing outside Room 400, which had already been
repaired, had resulted in leakage and caused mold to grow in that wall.
Flashing mounted on the surface, rather than in the
wall, may be a sign of flashing slapped on at the last minute, which fits
with the records of the project team that monitored the reconstruction of
the school in 2005.
Documents generated by the Oak Ridge Elementary School
project team show that the mold and moisture problems predate the school's
opening – and that at least some flashing in the school had not been done
by May 2005, when there were already students in the building and when
heavy rains caused several leaks in the brand-new roof of the building,
resulting in wet inside walls and puddles of water on hallway floors.
At that time, Chris Roth, the representative for HICAPS
Construction Management Services, which was managing the construction
project, reported that scuppers – drains to let water out of exposed parts
of buildings – had not been flashed to prevent leaks. Roth said the
contractor – Lyon Construction of Winston-Salem, or its subcontractor –
was trying to identify and fix the leaks, and that the roof was covered by
a warranty. Sources at the school say the contractor was called to the
school to fix roof leaks under warranty several times after 2005. The roof
is no longer under warranty.
The NIOSH team's preliminary report also suggested that
water could be leaking into the school's concrete foundation slab,
something that had been suggested by parents and teachers. The team found
surface drainage issues around the school, particularly between two of the
school's wings, and that a storm drain outside the library was blocked and
full of standing water.
"Such issues may lead to water infiltrating the
concrete slab," the team found.
The finding of new mold at Oak Ridge Elementary School
doesn't of necessity mean that the mold is causing the current health
problems at the school, or that the health department's fresh-air theory
is wrong. But it disproves the theory that the mold and problems and water
leaks at the school have all been solved. |