26 June 2015

Getting and Producing Liquid Natural Gas (LNG)

Getting and Producing Liquid Natural Gas (LNG)

Figure 1: Hydraulic Fracturing4
Natural gas, along with oil, is found in deposits that form below the ground in geological formations that consist of shales, which are tight rock formations that can be a mile or more below the earth’s surface2. To obtain the gas deposits people must drill into the subsurface using a combination of hydraulic fracturing and horizontal drilling.
Before drilling can start scientists use imaging technologies to locate the gas reservoirs2. When the reservoir is located drilling of the well can begin, which takes about 6 to 8 weeks2. Once completed, hydraulic fracturing (Figure 1) is used to release the natural gas from the tight shale formation2. The natural gas is then brought to the surface where it then gets transported to a pipeline to be distributed for processing and use2.
Figure 2: LNG Process5
Natural gas processing consists of several  stages (Figure 2).  First, the gas needs to be treated to remove impurities such as carbon dioxide and organic sulfur compounds since too much CO2 can raise the temperature at which the gas will freeze3.  Once these compounds have been removed, the gas must be dehydrated since the presence of water can cause the gas to freeze during the liquefaction process3.  Mercury is then removed since it is corrosive and can damage the LNG heat exchangers used in the liquefaction process3.
After all of the contaminants are removed, the gas is cooled down by a variety of  processes to a finished temperature of about -260 F (-160 C).  The finished product is then stored at approximately atmospheric pressure and then eventually transported.
The conversion of natural gas to LNG is a process that reduces its volume by about 600 times1. This reduction in volume is beneficial since the resulting product can be easily transported via cargo ships in high abundance. Once delivered to its destination, the LNG is heated to its gaseous state so it can be distributed to homes and businesses1.

Exponents correlate to references

Works Cited

1. Center for Liquefied Natural Gas. (2015). Basics. Retrieved from About LNG.
2. Texas Natural Gas Now. (2015). How We Get It. Retrieved June 24, 2015
3. The University of Oklahoma. (n.d.). Refrigeration Cycles. Retrieved from The University of Oklahoma.
4. Figure 1 taken from Total E&P Denmark B.V. (n.d.). What is Hydraulic Fracturing (fracking)? Retrieved from Total E&P Denmark B.V.: http://en.skifergas.dk/technical-guide/what-is-hydraulic-fracturing.aspx
5. Figure 2 taken from Goldboro LNG. (2012-2015). What is LNG? Retrieved from Goldboro LNG: http://goldborolng.com/about-lng/what-is-lng/

22 June 2015

Brownsville Resaca Watershed Stakeholder Meeting

Rancho Viejo Town Hall

3301 Carmen Ave., Rancho Viejo, Texas 78575

June 25, 2015  5:30 p.m. - 7:30 p.m.


Welcome and Introductions................................................................... Dr. Jude Benavides, UTB


TCEQ Stream Water Quality Program Overview..................................... Tim Cawthon, TCEQ


Determining Group Priorities (Watershed Map Exercise and Discussion) Jaime Flores, TWRI

Questions for Group:

1) What specific water bodies are important to you for protecting or restoring? Why?

2) What water quality concerns do you have for these water bodies?

3) How are these water bodies used and what uses are most important for protecting?

4) Can you describe the general drainage paths of the water bodies in this watershed?


Data Collection....................................................................................... Dr. Jude Benavides, UTB

Current and Planned Monitoring

Other Data Collection – What other data are available?

Data Needs?

Watershed Characterization Progress Update


Public Participation Plan................................................................................. Jaime Flores, TWRI

Watershed Study Area Name

Resaca Definition

Steering Committee Addition to PPP

Stakeholder Coordination Timeline

Other Sections of PPP Discussion

Other Business........................................................................................ Dr. Jude Benavides, UTB

Documents to stakeholders prior to next meeting

Next meeting-proposed meeting locations, dates and times

Topics for next meeting

12 June 2015

White Paper on Understanding Your Drinking Water Quality Report

Understanding Your Drinking Water Quality Report
            If you buy water for domestic use, each year you should receive an annual report from the water supplier. A water quality report is designed to let the consumer know of any contaminants in the local drinking water and how the contaminants may affect your health. Every report must contain certain information such as the source of drinking water, the susceptibility of the source of water to contamination, potential health effects of the contaminants that violate Environmental Protection Agency (EPA) health standards, information regarding Cryptosporidium and other microbial contaminants, contact information for the water system and EPA’s Safe Drinking Water Hotline (Food & Water Watch, 2008). Some water quality reports are hard to read and require knowledge to be able to decipher the jargon. This paper is designed to help water users understand their annual report. .
The levels of contaminants allowed in drinking water are set by the EPA. Once studies regarding the health effect of the contaminants are reviewed the EPA sets a Maximum Contaminant Level Goal (MCLG), which is ”the maximum level of a contaminant in drinking water at which no known or anticipated adverse effect on the health of persons would occur” (U.S. EPA 2013e). These are non-enforceable public health goals (U.S. EPA, 2013e). Since MCLGs consider only public health and not the limits of detection and treatment technology, sometimes they are set at a level which water systems cannot meet. The enforceable standard is known as Maximum Contaminant Level (MCL), which is ”the maximum permissible level of a contaminant in water which is delivered to any user of a public water system” (U.S. EPA, 2013e).  When there is no reliable method that is economically and technically feasible to measure a contaminant at low concentrations, a Treatment Technique (TT) is set rather than an MCL. A treatment technique is an ‘enforceable procedure or level of technological performance’ (U.S. EPA, 2013e) that ensures the control of a contaminant.
Table 1 Inorganic Contaminant

The above table was taken from the 2013 Annual Drinking Water Quality Report from a local city.  This report only provides information regarding the source of contaminants but not any information regarding the contaminants themselves. It is important to be aware of the health effects of any contaminants within your drinking water.
Arsenic- Linked to cancer of the bladder, lungs, skin, kidney, nasal passages, liver, and prostate (U.S. EPA, 2013a). Other effects can include thickening and discoloration of the skin, stomach pain, nausea, vomiting; diarrhea; numbness in hands and feet; partial paralysis; and blindness (U.S. EPA, 2013a).
Barium- Consumption of barium in excess of the maximum contaminant level (MCL) for many years could experience an increase in their blood pressure (U.S. EPA, 2013b).
Fluoride- Excessive consumption of fluoride may lead to increased chance of bone fractures in adults, and may result in effects on bone leading to pain and tenderness (U.S. EPA, 2013c). Children aged 8 years and younger with high exposure have increased chance of developing pits in the tooth enamel, along with a range of cosmetic effects to teeth (U.S. EPA, 2013c).
Nitrate- In infants below six months exposure above the MCL could become seriously ill and, if untreated, may die; symptoms are shortness of breath and blue baby syndrome (U.S. EPA, 2014).

Table 2 Radioactive Contaminants

The above table was also taken from the 2013 Annual Drinking Water Quality Report from the City of Edinburg.  This report does not provide background information about the listed contaminants, the following is a quick overview of the contaminants. Alpha particles, beta particles and gamma rays are three major types of ionizing radiation; which is when an unstable atom becomes more stable by emitting energy (U.S. EPA, 2013d). This emitted energy in the form of energy rays or high speed particles can displace electrons in the human body (U.S. EPA, 2013d). With prolong exposure of the above radioactive contaminants in excess of the MCL, the risk of cancer increases (U.S. EPA, 2013d).
Being able to interpret a water quality report helps people understand what is in the water that is consumed on a daily basis.  While water quality reports are meant to help people make informed choices about the drinking water these reports may be difficult to understand. Understanding your report and knowing about the listed contaminants may be beneficial to ones health.


Food & Water Watch. (2008, July). How to Read Your Water Quality Report. Retrieved May 29, 2015, from http://documents.foodandwaterwatch.org/doc/How%20to%20Read%20Your%20Water%20Quality%20Report.pdf#_ga=1.169948000.1335000660.1432925832
U.S. EPA. (2013a). Arsenic in Drinking Water. Retrieved May 29, 2015, from http://water.epa.gov/lawsregs/rulesregs/sdwa/arsenic/index.cfm
U.S. EPA. (2013b). Basic Information about Barium in Drinking Water. Retrieved May 29, 2015, from http://water.epa.gov/drink/contaminants/basicinformation/barium.cfm#
U.S. EPA. (2013c). Basic Information about Fluoride in Drinking Water. Retrieved May 25, 2015, from http://water.epa.gov/drink/contaminants/basicinformation/fluoride.cfm#
U.S. EPA. (2013d). Basic Information about Radionuclides in Drinking Water. Retrieved May 29, 2015, from http://water.epa.gov/drink/contaminants/basicinformation/radionuclides.cfm#
U.S. EPA. (2013e). Regulating Public Water Systems and Contaminants Under the Safe Drinking Water Act. Retrieved May 29, 2015, from http://water.epa.gov/lawsregs/rulesregs/regulatingcontaminants/basicinformation.cfm
U.S. EPA. (2014). Basic Information about Nitrate in Drinking Water. Retrieved May 29, 2015, from http://water.epa.gov/drink/contaminants/basicinformation/nitrate.cfm