• Word on the Street
• Children with Asthma Are Vulnerable to Low-Level Pollution, Study Finds
• Court Orders EPA to Rethink Policy on Carbon Monoxide Standards
• What Should You Do On An IAQ Investigation?
• What does it mean when I have high levels of basidiospores indoors?
• How to Handle a Sewage Contamination Disaster

IAQA CHAPTER PURSUES CHARITY OPPORTUNITY

Earlier this year the Ft. Lauderdale Chapter of the Indoor Air Quality Association (IAQA) worked with several local businesses to arrange an indoor air quality assessment on the home of a local family whose 5th grade son was diagnosed with cancer.

The chapter networked with other local community leaders and arranged for the complete assessment at no cost.

Shortly after the boy’s diagnosis, a medical team instructed the family on the environmental prerequisites required after his release from the hospital. The child’s elementary school, seeking information about indoor air quality testing and air duct cleaning, contacted Ft. Lauderdale’s IAQA Chapter Director, Maurice Baum, who started searching for solutions immediately.

“Their son’s unanticipated medical condition has imposed an unexpected and devastating emotional and fi nancial hardship on this young family” said Baum. “They are very grateful for the generosity and timeliness of our local professionals in their time of need.”

The Ft. Lauderdale Chapter of IAQA recognized COIT Services, Inc., Environmental and Analytical Management, Inc., and Wisconsin Occupational Health for donating their services to the family.

The Ft. Lauderdale Chapter of IAQA is still collecting donations from anyone who wants to help ease the financial burden of this family through services and/or financial contributions of any amount. To contact the Ft. Lauderdale Chapter of IAQA, call 877-663-5336 or email err2003@bellsouth.net.

Ben Auman is Chapter Relations Director for the Indoor Air Quality Association. He may be reached at (301) 231-8388, ext 11, or bauman@iaqa.org.

BBJ ENVIRONMENTAL ACQUIRED

The assets of BBJ Environmental Solutions, Inc. (BBJ) have been acquired by ACP BBJ, LLC an affiliate of Miami-based private equity firm Americas Capital Partners. BBJ manufactures and distributes a range of industry-leading products used to optimize indoor air quality and the energy efficiency of commercial air conditioning systems. ACP has appointed Robert G. Baker as CEO. Mr. Baker is the founder and former Chairman of BBJ.

According to ACP Senior Vice President David J. Matthes, BBJ came to the attention of ACP because the firm’s commercial real estate division has been using BBJ’s products with outstanding results for many years.

“BBJ makes a great product, our engineers love it. We were delighted when we got the opportunity to acquire this company” said Mr. Matthes. 

WHAT HAPPENS IN VEGAS

With its recent certifi cation by the US Green Building Council, the Palazzo resort in Las Vegas is now considered the largest “green” building in the world. The $1.9 billion, 3,000-room resort is more than four times bigger than any LEED-certified building, according to USGBC, which presented developer Las Vegas Sands Corp. with a Silver LEED (Leadership in Energy and Environmental Design) Certificate at an award ceremony this week. LEED certification is an independent, third-party verification that a building project is environmentally responsible, energy-efficient, and is a healthy place to live and work.

Key features that led to the Palazzo’s certification include: artificial turf, drip irrigation and moisture sensors in planted areas, resulting in a plus-75% reduction in irrigation needs and swimming pools heated with an expansive solar pool heating system. In the summer, the excess solar energy not needed for the pools is directed to the hotel’s hot water system; and air conditioning controls in guest suites automatically setback by several degrees when guests are not present and reset to the desired temperature upon return.

by Tom Scarlett

Children with asthma living in major cities may be particularly vulnerable to air pollution at levels below current air quality standards, including poor indoor air quality, according to new research conducted by the National Institute of Allergy and Infectious Diseases The study analyzes the short-term effects of outdoor pollution levels on asthma symptoms and lung function in children.

Using data collected from (NIAID) Inner-City Asthma Study (ICAS), researchers examined 861 children with persistent asthma, aged 5 to 12 years, living in low-income areas in seven U.S. inner-city communities: Boston, the Bronx, Chicago, Dallas, New York City, Seattle and Tucson. Over two years, the researchers regularly monitored the children's asthma symptoms, breathing function, and school absences, and obtained daily outdoor pollution measurements from the EPA's Aerometric Information Retrieval System. Every six months, they tested lung function twice-daily over a two-week period. They also asked the children's parents for their observations of their children's symptoms.

Results revealed that children had significantly decreased lung function following exposure to higher concentrations of the air pollutants sulfur dioxide, airborne fine particles, and nitrogen dioxide. Higher nitrogen dioxide levels and higher levels of fine particles also were associated with school absences related to asthma, and higher nitrogen dioxide levels were associated with more asthma symptoms. Because nitrogen dioxide is derived mainly from motor vehicle exhaust, these data provide evidence that car emissions may be causing adverse respiratory health effects in these urban children who have asthma.

Previous studies have documented the adverse respiratory effects of very high levels of outdoor pollutants. However, this study involves a larger cohort of inner-city asthmatic children and a more comprehensive evaluation of respiratory health effects than prior studies of this type.

The study's authors report that inner-city children with asthma experience adverse health effects from air pollutants even when air pollution levels are within the current air quality standards of the Environmental Protection Agency. These findings raise questions about the current air quality standards and suggest that part of overall asthma management for children living in inner cities may need to include efforts to reduce exposure to air pollutants.

The study was conducted by the Inner City Asthma Study Group (ICAS). ICAS was started in 1996 to examine environmental interventions in the management of asthma. During its 12-year history, ICAS has contributed to the understanding of childhood asthma and ways to minimize disease consequences.

The study was funded by NIH's National Institute of Allergy and Infectious Diseases (NIAID), National Institute of Environmental Health Sciences (NIEHS), and National Center for Research Resources (NCRR); and by the United States Environmental Protection Agency.

In another asthma-related development, new research suggests that free radical pollution in the air could be a cause of asthma, according to Dr. Duanne Sigmund, based at the University of Melbourne with the ARC Centre of Excellence for Free Radical Chemistry and Biotechnology.

Sigmund and Dr Uta Wille, both chemists at the University of Melbourne, have discovered that the atmospheric nitrate radical irreversibly damages amino acids, which are the building blocks for proteins in the human body. This, they suggest, could be a cause of some respiratory diseases.

The nitrate radical is formed by two common atmospheric pollutants; nitrogen dioxide, which itself is emitted from car exhausts, and ozone, which is an important greenhouse gas that is harmful to humans. During the day the sun’s UV radiation breaks down the nitrate radicals, but the concentrations rise as soon as the sun goes down.

"We were very interested to see what these nitrate radicals do to the human body since we breath them in at night," said Sigmund.

The duo has found that the nitrate radical reacts with amino acids to form compounds such as beta-nitrate esters, beta-carbonyl, and aromatic nitro-compounds. Some of these compounds have been associated with increased immune response in some respiratory diseases, creating worse symptoms.

"Our results suggest that the nitrate radical could be a real culprit for respiratory diseases, yet until this study the nitrate radical has been previously entirely overlooked in regard to causes for diseases such as asthma," says Sigmund.

The research will be published in the upcoming issue of the U.K. Royal Society of Chemistry¹s Chemical Communications.

by Tom Scarlett    

A U.S. District Court judge in San Francisco has decided that the Environmental Protection Agency violated the law and must reevaluate its standards relating to human exposure to carbon monoxide in the air.

The judge found that EPA violated a nondiscretionary duty to take a fresh look at the standards every five years. He gave the agency a deadline of May 2011 to come up with the new standards.

An EPA spokeswoman told Indoor Environment Connections that the agency believes the judge’s decision is wrong, and that it plans to appeal the case.

The appeal would go to the Ninth Circuit Court of Appeals in San Francisco, which is known for favoring claims filed by environmentalists and other liberal advocacy groups. The petition in this case was filed by four environmental groups. The decision could ultimately be reviewed by the U.S. Supreme Court. 

The 1990 revisions to the Clean Air Act require the agency to look at pollution limits, known as national ambient air quality standards, every five years and decide whether revision of the standards is needed to protect human health.

The EPA last reviewed carbon monoxide standards in 1994 and last revised the limits in 1971.

The agency admitted that it missed the five-year deadline, but began a review process last year and proposed to finish the review by October 2012.

White ruled, however, that it would be feasible for the EPA to finish the process by May 2011.

Carbon monoxide is created by the burning of fossil fuels in car engines and industrial plants. It is lethal at high levels and at lower levels can contribute to cardiovascular, nervous system and developmental problems.

Representatives of the groups that sued the EPA last year praised the ruling and urged the EPA to strengthen the standards.

Jeremy Nichols, director of Rocky Mountain Clean Air Action, said, "Sadly, current health standards allow our children to be exposed to dangerous levels of carbon monoxide across the country."

Shana Lazerow, a lawyer with Oakland-based Communities for a Better Environment, said, "Poor people and people of color suffer most from carbon monoxide, which is spewed by the refineries and power plants located in our communities, as well as the congested highways in our backyards."

Other groups participating in the lawsuit were the Coalition for a Safe Environment and Physicians for Social Responsibility.

In addition to setting a final deadline of May 2011, White ruled he has the authority to require interim deadlines in the review process.

He ordered the EPA to come with a proposed schedule of interim steps by July 7.

The judge wrote, "Given how many years have passed since the EPA's mandatory deadline has expired, the court is wary of merely providing the EPA a long-term deadline without any oversight or review."

The current primary ambient air standards for human exposure to carbon monoxide are an eight-hour average of nine parts per million and a one-hour average of 35 parts per million.

Communities for a Better Environmental said recent research studies have shown that exposure of fetuses to carbon monoxide levels as low as 1.4 parts per million over three months is linked to low birth weight, which in turn can lead to developmental problems.

The current national standard was set in 1971. Federal law requires a reassessment every five years, but the EPA last reviewed the standard in 1994 and made no changes, said Lazerow.

Environmental groups in the lawsuit cited two reports in the journal Environmental Health Perspectives, published in 2001 and 2005, both found low birth weights among children born to women who were exposed to carbon monoxide at levels far below those allowed by the 1971 standard.

The EPA says it has come up with a new approach to clean-air regulation that will streamline the process while incorporating the latest scientific information. But White, in his ruling, noted that the agency's own advisory panel of independent scientists called the new procedures "entirely unsuitable" in January, saying they failed to provide timely information about the contents of proposed regulations.

The decision comes at a time of increasing litigation against builders, landlords and others with claims relating to carbon monoxide exposure.

Eight lawsuits have been filed against companies involved with the heating system that malfunctioned at the Redstone Apartment complex near the University of Vermont in 2005, killing one person and sickening others.

When asked to write on the above topic, I realized that I could go off on many tangents.  Many of these directions are the subject of vigorous debate within the industry.  At this point, there appears to be little agreement on many of these issues.  Witness the difficulty IESO is having arriving at a workable Assessment Standard. 

So, I am writing this article from the basis of “my opinion”.  The value of which I will clarify with a quote from my old red-neck Uncle Jim:  “Opinions are like back-sides, we all have one.” 

I have always attempted to use the concepts of “best industry practices” or “standards of care”, and “best available science” in performing my inspections, writing remediation protocols, and giving advice.  But, with the differences of opinion in our industry, what are “best industry practices”? 

My practice as an IAQ Consultant as evolved over the years and I find myself involved more and more in litigation support (See the April 2008 issue of IE Connections).  This has recently led me to a concept that has impacted every area of my practice: 

“Creating a legally defensible position”.

The concept is simple, but far reaching.  It encompasses every aspect of business.  The question is simple:  Am I creating a legally defensible position for me, for my Company, and for my Client?  If yes, go forward.   If no, stop and re-think my approach.  I go forward only with a legally defensible position.

I had a very good Attorney tell me very early in my business career that contract law was simple:  “Say what you are going to do; and more importantly what you are not going to do.  Then, for God’s Sake, DO what you said you were going to do; and DON’T DO what you said you weren’t going to do!  If you follow those principals, how can you have created damages for someone to win a lawsuit against you?”

For the IAQ Consultant, the process of creating a legally defensible position starts by defining the scope of work for our services; which begins with the initial Client Interview, often started over the phone and completed at the first meeting.  What does the Client want?  Why do they want it?  What is their situation?  Who is involved?  What is their budget?  Is what is requested and what is actually needed?  Are other experts needed for the project?  Can I actually do what is requested?  These are important questions that must be answered in detail, often with follow-up questions needed to get the necessary detail.  And sometimes, you just have to walk away!

Let’s look at a couple of case studies and see how this concept of a legally defensible scope of work can be developed: 

CASE STUDY 1:  Potential Client (PC):  “Do you do mold testing?”

Frank Dean (FD):  “Yes, why do you want mold testing?”

PC:  “I’m on the Cleveland Clinic’s lung transplant list and my Doctor wants to know if my house is contributing to my lung condition.”  (Medical Condition, will have to sample for viable mold and bacteria, not just spore traps.)

FD:  “How long have you lived in the house?”  (Check for possible lawsuit against previous Owner or Builder.)

PC:  “About six years.”  (OK, probably no lawsuit.)

FD:  “When did your lung condition begin, or when did you start to notice symptoms?”  (Looking for some event that might be significant.)

OUTCOME:  I found, date coincident with the start of her illness, that they had replaced he furnace.  No one had told them that the humidifier on the furnace needed to be periodically cleaned, as it could be a breeding ground for mold and bacteria.  Also, they kept the old A-coil, now covered with six years of mold and bacterial growth.  Additional reservoirs of mold growth were found in both bathrooms.  Mold and bacteria were found to be blowing back into the laundry room from a blocked dryer vent.  Several deposits of guano were found in the attic surrounding bird’s nests.  I wrote a remediation protocol reflecting the above.  The house was successfully remediated by a remediation contractor.  A PRV inspection and sample set showed the areas had been successfully remediated.

Potentials for disaster:  You just do the requested mold sampling and don’t do a thorough inspection to find the other reservoirs of contamination.  The lady gets really sick.  They bring in another IAQ Consultant who finds the all the reservoirs of microbial contamination that you didn’t find.  Have you created a legally defensible position?

CASE STUDY 2:  PC:  “Do you do mold testing?”

FD:  “Yes, why do you want mold testing?”

PC:  “We just bought a house from that #@%&#!* Builder and the finished basement leaked during the last rain and there is Black Mold all over the drywall, and they don’t want to fix anything.”  (Probable lawsuit!)

FD:  “Who is the Builder.”

PC:  “It’s that no good #@%*@%&# XYZ Building Co.”

FD:  “Well, I’m on retainer with the XYZ Building Co. and I’m afraid that I cannot offer you further advice.”

OUTCOME:  I called the Divisional President of the XYZ Building Co. and told him about the call.  He overrode the Service Department and ordered that they fix the problem quickly.  Lawsuit avoided.

Potentials for Disaster:  You don’t find out who the Builder is before you take on the project.  Now you have a definite conflict of interest, and will probably lose the Builder as a Client.  Because you have an agreement with the Builder, it is possible that your report for the Homeowner will not be admissible and the Homeowner might be very upset.  Have you created a legally defensible position?

CASE STUDY3:  PC:  “Do you do mold testing?”

FD:  “Yes, why do you want mold testing?”

PC:   “I bought a condo from ABC Builders and we have numerous defects that have not been satisfactorily repaired under warranty, and now my wife and two year old son are noticing health symptoms.  We want to find out if these defects have caused mold to grow and cause our health issues.  (Probable lawsuit.  Wants determination that mold is in the building[OK, I can do that.], and that mold is causing the adverse health symptoms [Oh Darn, I can’t do that!  In a case decided last fall, the Ohio’s Supreme Court decided that only a Medical Doctor can determine or comment upon medial causality.  Not being a MD, I cannot comment on health issues!])

FD:  “ABC Builders is not a Client, so I can do the investigation and sampling that you are requesting.  But, you will need a Medical Doctor to comment upon the health issues.  Do you have a good Medical Doctor?   And, have you retained an Attorney?

PC:  “Yes, our allergist is Dr. Suzie Smith, and our attorney is Mr. John Howe, with the firm: Dewey, Cheetam and Howe.

FD:  “May I have your permission to contact Mr. Howe and discuss the particulars of the case.”

PC:  “Yes, I will call him and let him know it’s OK to discuss the case with you.”

OUTCOME:  I did a thorough investigation of the condo and found several construction defects that caused water intrusion and mold growth.  This mold growth was documented with air and surface samples (spore tramps and viables).  The Client’s Allergist said that it was highly probable that the mold caused the wife and small boy’s symptoms because they were allergic to several of the mold species found in the condo and the onset of their symptoms correlated with their move to the condo.  ABC Builders decided that it was to their advantage to settle the case and they bought back the condo.

Potentials for Disaster:  You do an inadequate sample set (in this case, no viables) and the MD doesn’t have the data she needs to determine causality.  Or, you are a “One-Day-Wonder”, someone who has taken a one day mold class and passes himself off as a mold expert, and you then you can’t pass muster as an expert witness (the Daubert challenge), so all of your data is inadmissible as evidence in Court.  Mr. Howe would not be pleased as he now has no case.  Have you created a legally defensible position? 

I have only presented three case studies to this point, but the possibilities for problems are endless.   I hope that you see other pitfalls in not completely determining and communicating your scope of work and knowing all of the parties involved before you take on the project.  All of the calls started with the same question, but went in totally different directions.

As part of your scope of work, you will have to decide:  “To sample, or not to sample?  That is the question.”  There seems to be a vigorous debate on the subject.  For me, it is simple.  The question is:  “How do you document that there is, or in the case of the PRV is not, mold present unless you test?”  Without documentation, you do not have a legally defensible position.

But, any sampling protocol must be based on a sound hypothesis.  What are you trying to find out?  What are you trying to prove?  This development of a sound sampling hypothesis and the resultant sampling protocol has been the subject of several articles in IE Connections by Dr. Harriet Burge, and others.  Find them and read them.  If you cannot state your sampling hypothesis clearly, so that any Jury can understand it, you are not operating from the point of good science, and do not have a legally defensible position.

CASE STUDY4:  PC:  “Hi Frank, I need to have some mold sampling done.”

FD:  “Why don’t you do it yourself?”  (The caller is a friend who is the Safety and Hazardous Materials Officer for a large hospital in a nearby city.)

PC:  “Can’t, I’ve got an employee complaining about his mold allergies.  It happened right after he got transferred into an office he doesn’t like.  He has written a complaint to OSHA with a letter from a Doctor, and I need an outside consultant to run the tests to avoid a conflict of interest.  I figure we will need 5 or 6 spore traps and 5 or 6 viables.

FD:  “What did the Doctor say about his allergies?”

PC:  “Doctor said the guy was allergic to Alternaria.”

FD:  “Great, Alternaria has a large, distinct spore.  We don’t need the viable samples to make the case.  It will cost you a lot less.”

OUTCOME:  I took spore traps at the guy’s desk, in the adjoining offices on both sides, in the hallway outside his office, and outside the building for control.  There was no Alternaria in any of the samples.  The complaint and complainer went away.

Potentials for Disaster:  Limited, because the Client was a friend.  But, because I saved her Hospital money, I’ll be first on her list to call in the future.

CASE STUDY 5:  Last year I developed and taught a mold class for a large corporate relocation company.  At one office, they told the story of a Seller who had mold problem.  He called his friend, an Industrial Hygienist, who advised him that since the US EPA and New York City Guidelines both assess a project by square feet of visible mold, he should make sure that there was no mold visible.  Then, when there is no visible mold, the Seller should call in the IH and he, the IH, would write a letter stating that on his inspection he saw no visible mold.  The relocation company used this report provided by the Seller, prepared by his friend, the IH, saying that there was no visible mold.  The relocation company bought the house for $240,000.00.

OUTCOME:  The corporate relocation company now owned the house.  A prospective Buyer hired an IAQ Consultant run air samples.  There were very high levels of airborne mold in the house.  Further evaluation found mold growth on the back of almost all of the basement drywall, and in two bathrooms.  Total costs to remediate, rebuild, hold and re-sell the house exceeded $160,000.00.  The relocation company now requires air samples for all the houses it buys. 

Potentials for Disaster:  You did a visual inspection for the relocation company and took no samples.  The company later finds a mold problem.  Their attorney calls you.  Do you have a legally defensible position?

Now, there may be some of you who have read to this point who are thinking it’s not like that out there.  What’s with all this focus on Law, we are not Lawyers.  We are IAQ Consultants.  Let me suggest that you might be more naive than you need to be. 

To some Attorneys, hopefully a minority, the practice of law is “blood sport”.  To them, the concept of fairness, morality, right and wrong are secondary to winning the case.  Some Attorney’s will do whatever it takes to win for their Client.

Since we never know when our reports will end up in Court; all of our reports should be written as though they will end up in Court.  This means that our inspections, any sample sets, and the report itself must be able to stand up to the highest levels of scientific and legal scrutiny.  You must realize that a good Attorney will get an independent IAQ Consultant to go over your report line by line, looking for ammunition to discredit you and your report.  I have been on both sides of this process, and it is not pleasant!  (Although, I must admit to getting some perverse pleasure from destroying a Home Inspector that has taken a one day sampling class who then does an inadequate, minimal sample set and doesn’t know why he has taken the samples or what the lab report means.)

Why did you do what you did?  What was your hypothesis for your inspection, and your sample set?  Are they scientifically valid?  Are they responsive to what your Client needs and wants?  Is your report “bulletproof”?  If you cannot answer these questions; have you created a legally defensible position?   

BIO:  Frank B. Dean, CIE, is an IAQ consultant based in Columbus, Ohio, doing IAQ assessments, training, consulting and litigation support throughout the Midwest.  His company, The PDF Group, LLC is an approved course provider for the IAQA.  Mr. Dean has spoken on IAQ issues nationally, including at the IAQA convention.  He is a frequent contributor to IE Connections.  He can be reached by phone at:  614-846-7100, or by email at:  pdfgrp@earthlink.net

Basidiospores are produced by all fungi in the class basidiomycetes.  The spores are the result of sexual reproduction, and are produced on small pegs on the surface of a club-shaped cell called a basidium.  The pegs are called sterigmata, which, in many cases, are specially designed to forcibly shoot the spore into the air.  The spores that are released in this way are bilaterally symmetric (instead of being radially symmetric as are most other kinds of spores).  Because of this bilateral symmetry we can recognize basidiospores as a class under the microscope.  Remember, however, that basidiospores that are not forcibly discharged do not have this distinctive shape, and generally are not recognized.  Fortunately, few if any of these are important in indoor air.

Basidiospores are abundant in outdoor air and are released from Basidiomycetes such as mushrooms, puffballs, shelf fungi, and others that produce large fruiting bodies.  Rusts and smuts also produce basidiospores.  In these groups, the basidiospores are very small, colorless, and thin-walled, and are easily missed on air samples.  Finally, there is a third group of fungi that produce basidiospores: the basidiomycetous yeasts.  These include the very common yeasts Sporobolomyces and Rhodotorula.  As with the rusts and smuts, yeast basidiospores are small, colorless and thin-walled.   

Now to the real question:  Do any of these fungi grow indoors?  The answer is “yes” and, in fact, some are relatively common indoors.  The most common are the basidiomycetous yeasts.  Both grow in wet places such as humidifiers, drip pans where water is cool, and continuously wet materials.  I have seen Sporobolomyces basidiospores as the most abundant spore type in a building, with concentrations exceeding 10,000/m3 of air using cultural sampling.  Actual spore concentrations were probably much higher.  Another group of Basidiomycetes that grows indoors is the wood rotting fungi such as Serpula and Poria.  These are in the same group as the “shelf” fungi that you see on trees in the woods.  Serpula produces brown curtain-like fruiting bodies, while Poria produces a thin white fruiting body that looks somewhat like paint.  Both of these fungi produce distinctive spores that could be identified specifically by a well-trained analyst.  Finally, in really wet environments such as might occur following a severe flood mushrooms may grow into the occupied space.  I have seen rows of mushrooms growing out of the baseboard in flooded buildings in Michigan.

This case study discusses a 3,400 square foot- condominium unit that became contaminated with sewage, the challenges that were posed, the testing methods used to determine effectiveness of remediation, and some unusual remediation methods that were eventually required.

Building and damage

The penthouse unit has three bedrooms and four bathrooms, and is located on the 20^th floor of a Florida Gulf Coast complex built in 2002. The present owners purchased the unit in December of ‘04.  Extensive remodeling began in April of ‘05 and was completed in March of ‘06. 

In all four bathrooms the new finish floor was travertine tile installed over the original ceramic tile.  The various layers of flooring materials in the bathrooms at this point consisted of:

o   Concrete slab

o   Adhesive

o   Cork

o   Thin set

o   Original ceramic tile

o   Cement board

o   Adhesive

o   Cork

o   Thin set

o   Travertine tiles.

By the time construction was completed, the new bathroom floors were elevated well above the original floor and flange connection to the commode drain lines.

Commodes were installed in September of 2005 and were in use from then until the discovery of the leaks.

The family moved in during March of 2006.  On May 13^th, they noticed wet drywall behind the commode in the master bathroom. 

A plumber investigated, looking first for plumbing leaks in the wall.  None were found. On detaching the commode, he found multiple stacked extenders had been used to compensate for the added floor height, rather than extending the drain line.

This assembly had been leaking for some time, probably since installation, as completely saturated flooring materials were found. The same condition was eventually determined to affect all four commodes.

Contamination

Commode installations had leaked at their connection to the flange.  Each time a commode flushed, contaminated water seeped out and began spreading on top of the concrete subfloor, under the multiple layers of flooring materials. By the time of discovery, “black water” had directly affected an irregular area of 100 to 250 square feet around each of the four commodes.

When water penetrated under walls into adjacent areas, contamination wicked up into wall materials and also affected the black walnut hardwood strip flooring in the rest of the unit.  This flooring had also been installed over previous materials, resulting again in multiple layers of flooring being affected.

Sewage composition

A wide variety of organisms are found in sewage.  Some are human pathogens. Many pathogens may be present, including bacteria (Salmonella, Shigella, Staphyloccocus), protozoa (Giardia, Entamoeba), parasites (worms and flukes), and viruses (norovirus, echoviruses).  Sewage pathogens vary in their characteristics, including resistance to desiccation, to changes in temperature or pH, and to contact with biocides.  After leaving the digestive tract, some die quickly. Others may be able to survive for weeks or even years in the right conditions.

Investigation

IET was retained to develop a scope of work and protocol for the necessary remediation. A primary concern of the homeowners was that they didn’t want to cover up still-contaminated materials when new materials were installed. They insisted on thorough documentation of return to sanitary conditions before reconstruction.

Various parties had input into the project, which led to IET performing several inspections to address different issues between June and December of 2006.

Sewage screen testing indicated the presence of indicator organisms (see discussion of sewage remediation testing below) on various materials, including concrete slab subfloors, in all the areas where flooring showed elevated moisture content. Finish flooring, hardwood and travertine, as well as the various layers beneath, had to be removed in order to access and decontaminate the concrete slab subfloor, while using appropriate precautions to prevent the spread of contaminants and to protect worker health. Wall materials were contaminated by sewage in some areas, and extensive mold growth not discussed in this article, were also issues.

IET developed a written protocol for the work and an experienced local mold remediation contractor was retained to do the work.

Remediation

To prevent cross-contamination of unaffected areas, containment was erected and negative pressure generated in the work zones. Any wall or flooring materials indicating elevated moisture content were removed down to the studs or concrete slab, which was then cleaned and treated with an EPA-registered biocide.  All surfaces inside the containments were thoroughly cleaned and treated with biocide.

IET was then contacted to perform a post-remediation evaluation.

Sewage remediation testing methods

As noted above, many pathogens can be present in sewage.  For a number of reasons, testing for all of them is impractical:

o   Many of the pathogens may be present in low concentration. However, it may require only a few to cause disease.

o   The statistical likelihood of detecting a low concentration of a pathogen in a sample from a small area is low.

o   Testing methods for particular pathogens may detect only one or a few pathogen types. Testing for all potential pathogens would require many tests, at high expense, even assuming tests were available for all of them.

For these reasons and others, sewage remediation testing is usually done by testing for "indicator organisms,” easily detectable bacteria usually found in a sewage-contaminated environment. While some bacteria in an indicator organism group may be pathogenic, indicator organisms are also used to extrapolate whether other less easily detected pathogenic organisms are present. 

In other words, testing is done to determine the level of cleanliness or sanitation. If indicator organisms are absent or are present at very low levels, we assume the level of sanitation is adequate. Typically, IET uses total and/or fecal coliform bacteria and Escherichia coli (E. coli) as indicator organisms.

Proper sewage remediation methods rely primarily on aggressive cleaning to physically remove contaminants, rather than on the use of biocides to kill pathogens.  One reason is that Gram-negative bacteria, very common in sewage-contaminated environments, may release endotoxins when they die, with potentially serious human health effects. Physically removing bacteria by thorough cleaning helps prevent release of endotoxins.

Nevertheless, biocides are extremely useful in sewage remediation, especially those biocides which provide both cleaning and biocidal capabilities.

Coliform bacteria

Coliform bacteria are often used as indicator organisms. A number of genera make up this group of rod-shaped, Gram-negative, non-spore forming bacteria. They include many human pathogens, as well as bacteria that form a normal part of a healthy intestinal flora and bacteria found in the general environment. The presence of coliform bacteria should not be considered a direct indicator of sewage contamination. However, the absence of coliforms on a surface that was previously contaminated with fecal material is an excellent indication that remediation has been effective and that a sanitary environment has been re-established at the point sampled.

Fecal coliforms

This subgroup of coliform bacteria is more directly associated with fecal contamination and is also used as an indicator organism for sewage contamination.

Escherichia coli: E. coli is one species of the coliform group and is another indicator organism IET uses when testing for sewage contamination.  It is found primarily in the intestinal tracts of mammals and on surfaces contaminated with feces. E. coli can sometimes survive outside the body for extended periods. Most strains of E. coli are not pathogenic and indeed form a normal part of human intestinal flora.  E. coli can even be beneficial to human health by producing vitamin K and limiting the establishment of pathogenic bacteria.

When testing for residual contamination after sewage remediation, the presence of E. coli is considered a direct indication of human fecal contamination, although there are other potential sources. 

Screening vs. quantitative analysis

Most of the time, IET uses a “Coliform and E.coli screen.” This qualitative analysis determines the presence or absence of E. coli and of total coliform bacteria.  It provides no data about how many of these organisms were present. This means it is possible for a quantity slightly above the lower detection limit, an amount that doesn’t necessarily indicate a significantly contaminated environment, to generate what is in effect a false positive.

A quantitative “Sewage Assessment/Clearance” analysis provides more information and is usually used for the final post-remediation evaluation. It may quantify total coliforms, fecal coliforms and E. coli, allowing the consultant to make decisions about whether the numbers found indicate a contaminated surface or environment.

Results of post-remediation evaluation (PRE) and follow-up work

After about two months of remediation work in early 2007, which addressed mold remediation as well as sewage contamination, remediators contacted IET to perform a post-remediation evaluation.

February 27 (PRE) inspection:  Mold remediation was successful.  Sewage remediation testing, using screening methods, showed that remediation had been successful in some areas, but not in others.  IET made suggestions to the remediators on appropriate remediation methods and additional work was completed.

March 15 (PRE) inspection:  Sewage remediation testing, using screening methods, found that remediation had been effective in some more areas, but other areas were still contaminated. IET again discussed appropriate remediation methods with the remediators and additional work was done.

April 02 (PRE) inspection:  Sewage remediation testing, using screening (presence/absence) methods indicated successful remediation in additional areas, but other samples still showed contamination.  After discussion with the owners, it was decided to use quantitative analysis in case the qualitative screening was producing what “false positives” by showing the presence of coliforms when they were present only at very low levels.

April 05 (PRE) inspection:  Quantitative analysis using the Sewage Assessment and Clearance method found fecal coliform bacteria in significant quantity in some samples.

We were not expecting these results, especially considering the extended time, about 9 months, since additional contamination had stopped. Previous sewage remediation projects had been successfully remediated using the techniques specified. One possible explanation is that micro-organisms had been able to form biofilms, complex microbial communities attached to a surface and encased in a slime matrix. Microbes in a biofilm may be much more resistant to desiccation, to mechanical disruption, and to detergents and biocides.

As repeated attempts to decontaminate surfaces had not been fully effective, IET decided to directly supervise further remediation work. The remediation contractor provided workers and equipment, and IET located specialized equipment for use on a rental basis.

Remediation processes used

1.  Thorough cleaning: IET used a large rotary scrubber with a stiff bristle brush to scrub the concrete aggressively.  The solution used was a quaternary ammonium based cleaner/disinfectant. It was not EPA-registered for sewage remediation and was used primarily for its cleaning potential.  Any biocidal effect was a welcome bonus.

Rationale: Previous cleaning attempts may not have been aggressive enough to disrupt possible biofilms. The porous surface of concrete, as well as paint and adhesive residues, provide crevices in which bacteria can “hide,” and into which biocides and cleaners may not be able to penetrate effectively. Aggressive cleaning methods might be more effective at disrupting biofilms, dislodging sewage organisms and/or encouraging penetration of biocides into pores.

2.  Through rinsing and extracting: IET used a high-pressure washing/extraction system designed for cleaning floor tile.  900 psi rotary spray jets “flushed” contaminants out of pores. The spray jets were enclosed in a vacuum hood, so there was no overspray with its potential to aerosolize contaminants.  Soils and contaminants were collected by the vacuum system before they could sink back into the concrete pores. To prevent aerosolization of contaminants, vacuums exhausted to the exterior.  Dehumidification controlled humidity.

Rationale:  Effectively removing suspended soils and contaminants from a porous surface is difficult, since after being suspended in a cleaning solution soils often redeposit before they can be extracted or absorbed.

Normally, a tool of this type connects to a truck-mounted carpet cleaning machine providing high heat, water pressure and vacuum.  This was impractical for this project, located on the 20^th floor.  IET rented a portable extraction machine capable of operating the equipment.

3.  True steam cleaning:  After rotary extraction, the surface of the floor was allowed to dry, and then a rented “true steam” cleaning machine was used.  This professional unit generates a significant volume of steam at 350°F. Steam is even more effective at penetrating surface pores of concrete than high-pressure rotary extraction and may also have direct biocidal effects.  Micro-fiber towels over the steam jets absorbed soils released from the surface. 

4.  Application of disinfectant solution:  IET used a phenolic-based product EPA-registered for sewage remediation. The product was applied in compliance with label instructions and allowed to dry for several hours.

            Sample results showed that all areas sampled were below the lower detection limit of the analysis.  IER was able to contact the owners and inform them that the environment had now tested as sanitary and that reconstruction could begin.

Lessons learned

When a concrete slab has been soaking in sewage for weeks or months, thorough cleaning and sanitation can be challenging. It is possible that biofilms can form and significantly increase resistance to desiccation, detergents and biocides.

Aggressive cleaning, including the use of efficient methods for removing suspended soils and contaminants before they redeposit, is essential.  Aggressive remediation using methods such as those described, even when rental of specialty equipment is required, is likely to be a good deal more cost-effective than repetitive ineffective remediation attempts combined with repeated sampling.

Mold remediation is usually done under conditions that are as “dry” as possible to help prevent further amplification.  This approach may be counter-productive in sewage remediation, for which aggressive cleaning methods with large volumes of water may be more effective.  The remediator’s challenge is to use enough water for effective cleaning while still controlling it well enough to prevent wetting of adjacent materials or the development of excessive humidity.

Timothy D. Toburen is an Indoor Environmental Consultant for Indoor Environmental Technologies, based in Clearwater, Florida.  He has worked in the restoration, remediation and environmental consulting industries for over 35 years, serving on the committees that produced both the IICRC S520-2003 Mold Remediation and S500-2006 Water Damage Restoration standards.  He can be reached by e-mail at ttoburen@ietbuildinghealth.com or by phone at (727) 446-7717.

Will Spates is President of Indoor Environmental Technologies, based in Clearwater, Florida. He has over 20 years of experience in the environmental consulting industry. He can be reached by e-mail at wspates@ietbuildinghealth.com or by phone at (727) 446-7717.