Xenco Laboratories has once again received an “A” Vendor Grade from TCEQ for our performance. Texas reviews all of its vendors annually. The “A” Grade has been granted because Xenco delivers the best value for service, complies with all specifications and evaluation criteria, and has been in full compliance with TCEQ’s high standards.
Our thoughts are with the countless families and businesses that have suffered in Texas as a result of Hurricane Harvey. During this crisis public health is a major concern. Please reach out to us if we can assist with your environmental testing needs. We are fully operational and ready to support your environmental testing needs in the aftermath of this catastrophic event.
Our Stafford lab in the Houston area is now accepting shipments and walk-ins. Our operations have returned to normal and we are grateful that our facilities were spared during the Harvey Hurricane and subsequent floods. We want to thank all our clients for their patience and support during this event.
Due to continuing extreme flooding in Houston as of Tuesday August 29, we would like to ask all our clients that ship samples to our Stafford laboratory, which is located in a Houston suburb, to ship all samples temporarily to our Dallas lab until Thursday of this week, August 31st. Use this shipping address:
9701 Harry Hines Blvd
Dallas, TX 75220
Our Houston facility has been spared from the flood, thankfully, but due to road conditions, to our employees safety, and to airport closure, we are only keeping an emergency crew that is handling rush and emergency-response samples in our mail lab. Houston airports are expected to reopen on Thursday August 31st, so please wait until that date to start shipping back to our main lab at Stafford.
The expected effects of Hurricane Harvey are very likely to disrupt our operations at Xenco. While we are fully prepared internally to offer regular and emergency services, things outside our control such as disruption in shipment by FedEx, power outages, and serious transportation problems are likely to affect the timeliness of our regular and rush testing. The hurricane is expected to cause problems starting today, Friday the 25th and possible until the middle of next week. We apologize for the inconveniences this may cause our clients.
Bioremediation of hydrocarbons is not difficult. The problem is that bacteria and
fungi have very small stomachs and eat slow. The two components needed for
bioremediation is moisture and nutrients. Moisture should be kept at about 20%
and nitrates at about 20 ppm.
There are plenty of naturally occurring bacteria and fungi in soil to promote
bioremediation. Addition of store bought cultures is not necessary. Often, the
majority of organisms in commercial cultures die when introduced to the
environment because it is foreign to the incubated tanks where they were
developed. Fungi are the main organism doing the remediation, not bacteria.
There are 10,000 times more fungi in soil than bacteria. Little is heard about the
fungi role in bioremediation because fungi are not widely studied, difficult to
culture individually, and there are many species not named. To understand how
aggressive fungi are in bioremediation, look at wood decay in forest due to fungi.
The rotting branches and trunks are due to fungi using them for food. If fungi can
break down wood, they certainly can eat hydrocarbons.
Bioremediation occurs efficiently when the fungi and bacteria (bug) population is
high and thriving. For this to occur they need food, the hydrocarbons, nutrients,
the nitrate, and moisture. The goal is to maximize the bug population and keep
the population high. To do this the nitrate need to be kept at about 20 ppm and
moisture has to be kept at least 20%. When either of these parameters drop, the
bug population drops and the rate of bioremediation decreases. When optimum
conditions return, then the bug populations must regrow in order to have a high
rate of bioremediation. If the nutrients and moisture are constantly bouncing up
and down, bioremediation will be very slow because the bug population does not
maintain a high level.
The bioremediation should be monitored for TPH, nitrates, and moisture every
two weeks or monthly. The material should be mixed by tilling once every month
or two. Depending on the TPH level desired, bioremediation may take 4 mo to
year depending on field conditions. Cooler weather will slow the bioremediation
It is very important that homogeneous, representative samples be taken. The site
should be initially tilled and completely mixed to make as homogeneous as
possible. When sampling, 10 subsamples should randomly be taken and
composited to one sample for testing. It is suggested that the subsamples be
mixed in a plastic bag for the composite before transferring a portion to a 4 oz jar.
The strongest and most representative data would be to take 3 composite
samples, especially on large sites. The data will bounce high and low over time if
representative homogeneous composite samples are not taken