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LSU Health Sciences Center: Preparing for Restoration
 The
Problem
The multi-building campus of the Louisiana State University (LSU)
Health Sciences Center in New Orleans, Louisiana, was one of the
many properties impacted by the storm and floods of Hurricane
Katrina. Though the Health Sciences Center buildings survived, they
required extensive cleaning and remediation. A year after the
storms, questions still remained about the suitability of the
damaged areas for restoration and the potential for hidden damage or
contamination.
Chelsea Group, Ltd., was retained by Duplantier & Meric,
Architects, LLC, on behalf of LSU to observe conditions, collect
samples, and obtain laboratory analysis of materials relevant to the
recovery and future use of areas of the Health Sciences Center
campus that were impacted by Hurricane Katrina. The primary concern
of this project was to verify whether the buildings required further
remediation or cleaning of building assemblies or materials, and to
identify any potential for the presence of chemical or biological
agents that would threaten the future use or pose concerns about
environmental health and safety or disease transmission.
Chelsea Group assembled a team of engineers, materials
scientists, and other experts, including specialists in-house and
from Wiss, Janney, Elstner Associates, a global leader in
construction problem solving. The team gathered at LSU to observe,
conduct field tests, and collect samples for laboratory tests.
Chelsea Group Intervention
The Chelsea team conducted visual observations of both exterior
and interior conditions in the lower floors of the ten buildings.
Initial observation of building surfaces indicated typical and
generally unremarkable debris and dirt. The visual survey
observations included the following:
- Initial remediation after the storm was generally effective
at removing debris and cleaning surfaces.
- Evidence was found of corrosive salt water damage to metal
brackets that support granite panels; if the metal is not
thoroughly cleaned or replaced, the granite panels will
eventually fall off the walls.
- Stains at the flood line on exterior and interior granite do
not appear to affect the structural integrity of the granite.
 Chelsea
Group then began to look for hidden damage. Chelsea Groups protocol
involved destructive sampling and collection of materials from newly
exposed surfaces. For example, all of the granite wall panel samples
were collected from the unexposed side of the panel shortly after
removal from the wall. Similarly, samples of the base material and
mortar beneath the pavers were collected immediately after the paver
core was removed. Samples were collected from hidden water
beneath some of the buildings. Care was taken to avoid the
introduction of contaminants related to removing or exposing the
sampled materials. Focus was on the surfaces not exposed to the
general environment in order to minimize the impact that weathering
and/or cleaning could have had on the residual materials.
The Chelsea team conducted field testing including frost point
testing of insulating glazing units, pull-off strength testing of
coating adhesion, tape adhesion testing of coatings and films,
adhesive bond testing of pavers and tiles, and field chloride
testing. Samples were taken for laboratory material studies
including visual microscopy, petrographic examination, LECO sulfur
testing, X-ray diffraction analysis, Fourier Transform Infrared
Spectroscopy analysis, and water-soluble chloride testing.
 Biological
Sampling
The biological field sampling technique generally involved
swabbing the surface of newly exposed material. In some cases, bulk
samples of sand or mortar were collected for biological analysis.
One bulk sample of flood water that had been recovered from one of
the buildings was available for testing. The target biological
contaminants selected for analysis included fecal bacteria, Shigella
species, hepatitis A virus, Giardia, and Cryptosporidium.
Immediate Results: All samples were reported as none
detected, indicating no significant residual biological or
sewage contamination in the tested buildings.
Chemical Sampling
The Chelsea team collected samples for chemical analysis by
removing material directly from potentially impacted building
components, such as granite wall panels, or material directly
adjacent to the potentially impacted building components, such as
sand from beneath a floor slab. The samples were analyzed for a
slate of possible contaminants based on EPA recommendations, 39
total including 8 metals, 10 volatile organic compounds, 12
semi-volatile organic compounds, 2 common herbicides, and 7
pesticides.
Immediate Results: Tests showed no significant
concentrations of chemical contamination, especially related to
petroleum, agricultural, or industrial sources. Trace amounts of
chromium were detected in a few samples, still significantly
below any noted level of concern for this metal. Chloride was
found in many areas; because it could cause damage to metal
building components, Chelsea Group recommended cleaning or
replacement of those components.
Building Structure Analysis
 Potential
corrosion due to chloride contamination is of particular concern in
many of the buildings. For example, the hollow core steel door at
the first floor level of a parking garage was more heavily corroded
than the similar door at the second floor. It is possible that this
heavier level of corrosion is related to the immersion of this door
during the flood. Since the interior core of the door is filled with
batt insulation, moisture in the core could wick upward, cyclical
condensation could occur on the doors interior, and all interior
surfaces of the door would be exposed to unusual levels of moisture.
The chloride detected here will promote accelerated corrosion of the
steel door.
- Other flood-related defects identified in the buildings
include
- Damage to interior gypsum-based plaster wall finishes
- Localized damage to coatings on wall surfaces
- Staining of granite cladding panels, both interior and
exterior
- Loss of adhesion of opacifier film on spandrel glass
- Scratches in vision glass coatings
- Cracking and spalling of concrete parging
- Damage to wood furring elements in exterior wall
construction
After planned renovations, the buildings can be occupied.
However, without careful cleaning or repair, the long-term service
life of some building materials and systems will be reduced. In some
cases, replacement is recommended.
Final Results
Based on the extensive field assessments and the results of
laboratory analysis of the samples taken at the Health Sciences
Center campus, Chelsea Group found:
- No evidence of significant concentrations of the target
biological agents related to sewage contamination in any of the
materials collected
- No evidence of significant concentrations of residual
contamination from the targeted 39 chemicals and compounds that
would reflect petroleum, agricultural or other industrial
sources impacting the buildings
- No evidence of likely environmental health impact from the
targeted chemical and biological agents by occupancy of the
buildings
- Based on these findings, further remediation would not be
required for the targeted chemical and biological agents in any
ongoing demolition or construction work
Chelsea Group provided some specific recommendations for repair
and renovation:
- Where chloride contaminated metal building components such
as doors and brackets, the components should be removed and
cleaned or replaced
- Plaster finishes should be removed, replaced, and repainted
- Areas of localized paint failure should be cleaned,
spot-primed, and topcoated
- Spandrel glass units with delaminated opacifier film should
be replaced
- Localized areas of damaged parging should be replaced
Chelsea Group reported that there was no evidence of significant
biological or chemical contamination and no need for further
remediation on the Health Sciences Center campus. Building
management could move ahead with plans to renovate and reoccupy the
buildings, and tenants could be assured that they and the buildings
faced no environmental health concerns. However, Chelsea Group
findings related to the damage to window, wall, foundation,
structure, and finish elements pointed to the need for much more
extensive repair of the basic fabric of the buildings. These issues
must be resolved to assure that the renovation will restore the
buildings to their full utility and lifespan.
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