Monday, March 27, 2017

Citizens seek action to protect our health, property, and drinking water supply

On March 22, the Acadiana Group of the Sierra Club and the WaterMark Alliance delivered a letter to local Lafayette leaders asking for immediate actions responding to contamination of our Chicot Aquifer water source and abandoned railyard site downtown. An article in The Independent by Wynce Nolley titled Green alliance offers advice to LCG on water contamination describes this letter and provides additional background information.

Express your opinions and concerns to the Lafayette mayor-president and council! Contact them by phone, email, or postal mail. Contact details for all these leaders are available in the previous post titled Who is my council member? Who is the mayor-president? How do I contact them?

The March 22 letter states in part:
"The contaminated railyard site next to our downtown and residential neighborhoods perches above water wells that provide much of our municipal water supply. Beyond the obvious risk to neighbors’ health and property resulting from this un-remediated site, we now see clear evidence that it is contaminating our aquifer. Currently, we are pumping millions of gallons of water every day from the LUS water wells near sites of contamination. This continued pumping poses a threat to our aquifer and the future health and prosperity of our city."
Evidence of contamination appearing in LUS drinking water wells was presented at a January 19 meeting organized by the Sierra Club. The measured concentrations are below EPA Designated Contaminant Levels and are measured before treatment. However, contaminants reaching our water wells “present a warning to the public and our civic leaders that action is needed” said Harold Schoeffler, chair of the Sierra Club Acadian Group. Attention has been focused on the abandoned railyard in downtown Lafayette since DOTD has revived their plan to construct I-49 over the railyard site which is known to be contaminated with toxic substances including some of those being monitored in nearby LUS wells. Schoeffler went on to say that “both property and public health require protection.” A  March 22 letter from the Sierra Club Acadian Group and the WaterMark Alliance to Lafayette Mayor/President Joel Robideaux and Council members makes the following ten recommendations:

  1. Plan and execute a study of surface contamination within the wellhead protection area of our wells. Include sampling for all contaminants that have been monitored in LUS well water, and for contaminants found at other US rail sites which are either undergoing or have been remediated.
  2. Where appropriate, partner with other state and federal agencies.
  3. Intensify sampling of well water by increasing the frequency of sampling and adding contaminants for analysis to include all known or suspected contaminants present on the surface or in the surficial aquifer (groundwater just below the surface).
  4. Make all past and current well monitoring and sampling data easily available for public review and analysis.
  5. Begin contingency planning for shutting down all wells in the vicinity of the North Treatment Plant. Abandoning some or all of these wells may be necessitated in the future to allow aquifer remediation through recovery well operation or other groundwater cleaning technology.
  6. Identify responsible parties and methods to recover ratepayer and taxpayer costs.
  7. The abandoned railyard site is a public hazard and should be posted as such. It is known to be contaminated with arsenic, asbestos, lead, and many other contaminants which endanger public health from dust and direct contact.
  8. Public access and parking of any vehicles on the abandoned railyard site should be immediately prohibited.
  9. Determine new protection measures to be fully integrated into policy.
  10. Ordinances based on LDEQ drinking water protection sample ordinances should be drafted and adopted.

Schoeffler hopes to see a response to these recommendations at future meetings of the Council and Utility Board.

The letter's civic leader recipients were:

  • Joel Robideaux, Mayor-President
  • Kevin Naquin, Council Member District 1
  • Jay Castille,  Council Member District 2
  • Patrick Lewis, Council Member District 3
  • Kenneth P. Boudreaux, Council Member District 4
  • Jared Bellard, Council Member District 5
  • Bruce M Conque, Council Member District 6
  • Nanette Cook, Council Member District 7
  • Liz W. Hebert, Council Member District 8
  • William G. Theriot, Council Member District 9

Copies of the letter were provided to Terry Huval, P.E., Director, LUS, and Craig Gautreaux, Water and Wastewater Operations. Manager, LUS. A copy of the signed letter is attached below or can be viewed online by clicking here.
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Wednesday, March 22, 2017

Who is my council member? Who is the mayor-president? How do I contact them?

Lafayette City-Parish Council

Do you know your Lafayette Parish Council district number and your council member's name? If not, the city-parish makes it easy to find out. Follow this link to the Lafayette Parish Council web site and click on Council Districts map or to find your Council Member

Once you know your district number, you can find contact information from the Clerk of Council handout shown here 

Mayor-president Joel Robideaux
Now, how about our mayor-president? Our current mayor-president is Joel Robideaux, His contact information from his LCG web site is:
Phone: (337) 291-8300
Mailing Address: PO Box 4017-C, Lafayette, LA 70502

When you do meet, phone, write, or email our civic leaders, I suggest that you start the exchange on a positive note. Thank them sincerely for their time and/or service to the community. Perhaps mention other areas where their support has helped you or the community. Then, ask for their help and support on the specific issue that led to you contacting them. Even when you do not succeed in getting their support, you may at least soften their opposition by showing that you have well thought out ideas.

If you do contact our leaders, and if you choose to share your experience, please tell us about it in a comment to this post.


Congressman Clay Higgins can be reached at his local office at 337-849-1662, and by email at His government web page is and Facebook page is

Tuesday, March 14, 2017

More Evidence of Chicot Aquifer Contamination: USGS Monitoring

SUMMARY: The United States Geological Survey (USGS) established a monitoring well at our Lafayette North Water Treatment Plant in 2001. This well was drilled to a depth to sample the top of the Chicot Aquifer. The water plant and monitoring well are located near known surface contamination. Data collected from this well since 2001 demonstrate that in spite of the existence of a clay confining layer above the Chicot Aquifer, contaminants flowed down into the aquifer which is our sole source for drinking water in Lafayette Parish. These findings are consistent with other evidence, and support the recommendation that action is urgently needed to protect our Chicot Aquifer.

Old rail lines and railroad maintenance and switching yards are typically contaminated with a long list of toxic substances including arsenic which was extensively used at rail sites as a preservative for railroad ties, poles and structures, as a weed killer, and as a pesticide. Citizens are concerned because our north drinking water treatment plant and many of our Lafayette Utilities System municipal water wells are adjacent to the old rail line and just north of the former Lafayette railyard.  

Lafayette's municipal wells draw our drinking water from the Chicot Aquifer which has been designated as our sole-source aquifer. Parish citizens have been assured that our local geology protects our sole-source of drinking water from contamination because an impermeable clay confining layer separates the contaminated surface from our water well intakes deep in the Lower Sand formation of the Chicot Aquifer. This assertion of protection has been made for decades despite clear evidence that it isn’t true. I will provide additional evidence of this contamination in a future post. Here, I describe observations of Chicot Aquifer arsenic contamination in samples from the monitoring well at the downtown Lafayette North Water Treatment Plant.

USGS Monitoring Wells
In 2001 through 2002, the United States Geological Survey installed 28 shallow monitoring wells throughout Lafayette Parish (Figure 1) to survey levels of shallow groundwater contamination (Fendick and Tollett, 2004). Wells were placed in urban, residential, and light commercial areas. These wells were drilled to a depth that reached the top of the upper sand of the Chicot Aquifer (Figure 2). This monitoring was a part of the USGS National Water Quality Assessment Program.

Figure 1. Lafayette Parish monitoring well locations from Fendick and Tollett (2004).

Cover1-Fendick+Tollett-2003-report-4118.jpg  Cover2-Fendick+Tollett-2003-report-4118.jpg
Figure 2. Photos of monitoring well installation from Fendick and Tollett (2004).

One of these wells designated well number 116 in the report (USGS site 301355092005601) was installed at the Lafayette North water treatment plant. The well was drilled to sample water from 55 to 65 feet below surface in the Upper Sand of the Chicot Aquifer. This site is near several of our municipal water wells, and is within a few hundred feet of railroad track which has been in use for over a century (Figure 3).

Figure 3. Google maps image showing the approximate location of monitoring well 116 as red marker in upper right of the image (personal communication, Rolland Tollett, 2017). Note the proximity of the well with the railroad track which parallels Sherman St.

Arsenic Contamination
Among all the 28 Lafayette Parish monitoring wells, well #116 at the Lafayette North Water Treatment Plant had the highest measured arsenic concentration (Figure 4.). Arsenic and creosote are the most common contaminants associated with rail operations that occurred from the 1800s up to the 1960s (Connector Comments, 2017). Arsenic was used as a wood preservative for rail ties and other wood, for killing weeds, and for killing pests. Arsenic contamination is also a legacy contaminant in areas that were cotton fields in the 1800s and first half of the 1900s. It is not the topic of discussion here, but it is interesting to note that well #113 which has the second highest arsenic concentration (Figure 4) is located at the LUS South Water Treatment Plant. The South Treatment Plant is surrounded by agricultural fields which may have legacy arsenic from pesticide applications, and has a total water production capacity similar to the North Water Treatment Plant. Pumping at both plants may be increasing the rate with which contaminants are drawn into the Chicot Aquifer.

Figure 4. Well ID numbers are displayed on the vertical axis. Arsenic concentration measured from 2001 to 2002 in micrograms per liter as arsenic from the 28 Lafayette Parish monitoring wells in Lafayette Parish show well 116 (solid red bar) had the highest concentration of 5.7 ug/L  (Fendick and Tollett, 2004).

Figure 5. Arsenic concentrations at well #116 continue to be elevated throughout all available monitoring history  (Fendick and Tollett, 2004).

Frederick and Tollett (2004) also used CFC concentrations and other data to estimate the apparent age of the groundwater in the Upper Sand of the Chicot Aquifer in Lafayette Parish. They found the apparent age of the groundwater varied with water level and ranged from about 12 to 50 years with a median of less than 32 years. Well #116 at the LUS North Water Treatment Plant had an apparent groundwater age of 41 years. Water age estimates the average time that water has been present in the underground formation. Therefore, the contaminated water contributing arsenic to the mix is probably much younger than the average age which should include at least some very old water. These CFC age estimates are further discussed by Darling (2005). Those findings provided clear evidence that groundwater recharge from surface water is common throughout Lafayette Parish, and this local recharge can lead to groundwater contamination.

Well Water Level
Data shows that the water level (termed the static head which is a measure of the pressure in the aquifer) in well #116 is dropping over time. Water level in this well in November 2001 when it was first measured was 45.72 feet below land surface. In the most recent available measurement taken in April 2014, the water level had fallen to 48.56 feet below ground surface. The observed head confirms that the well is indeed sampling within the Upper Sand of the Chicot Aquifer, and that there is a strong hydrologic connection between this sand and the Lower Sand below it where most of our drinking water is withdrawn. The large difference in head (i.e. pressure) between the surface aquifer above and the Upper Sand of the Chicot aquifer below it drives a flux of water and contaminants moving into the Upper Sand. A future post may provide further interpretations of Chicot Aquifer groundwater head measurement data.

Figure 6. Head of water observed in well #116 in feet below the ground surface is plotted. Elevation of the ground surface at the well is 39 feet (1929 NGVD). The solid red line is an Excel generated trend line through the data points which is dropping at approximately 2.6 feet per decade.

Lafayette Parish inherited a plentiful and sustainable drinking water resource in the Chicot Aquifer. The findings presented here, as well as numerous other lines of evidence, lead to the conclusion that the Chicot Aquifer in Lafayette is at risk. Although a confining layer may impede flow, it does not stop surface contaminants from entering and contaminating the aquifer. Data from USGS monitoring well #116 demonstrates that surface contamination in the vicinity of a number of our Lafayette municipal water wells has and does reach the Chicot Aquifer.

The Chicot Aquifer is a resource which could provide water resources for many future generations. It is our responsibility to protect this inheritance. However, neglect and mismanagement can rapidly destroy this legacy.
The data presented here were downloaded from the USGS online National Water Information System (NWIS) public data server. Except where cited, all interpretations and opinions are those of the author, Michael Waldon.


Fendick Jr, R. B., and Tollett, R. W. (2004). "Quality of Water from Shallow Wells in Urban Residential and Light Commercial Areas in Lafayette Parish, Louisiana, 2001 Through 2002." Water-Resources Investigations Report 2003-4118, US Geological Survey.

Thursday, March 2, 2017

Why are there high levels of arsenic in some Acadiana soils?

Figure 1. "4 Sources of Arsenic You’d Never Expect"

Introduction - The issue of arsenic contamination may at first appear to fall outside the scope of I-49 Connector (The Con) questions. However, arsenic contamination of our soils is an issue that does intersect with The Con's issues. In this post I will give some background about how elevated arsenic came to be in our parish soil, how it can impact us, and what we need to do about it.

If you recall the periodic table from your school days, arsenic is chemical element number 33 with the symbol As. Arsenic falls in the table just below phosphorus in column 15, and this means that arsenic may react in ways that are similar to phosphorus and disrupt some chemical reactions that are essential to life.

Sources of arsenic contamination - Arsenic was used for many purposes in the past, but is much less widely used today. In the southern US, arsenic pesticides in the form of lead arsenate dust and other formulations were regularly used on cotton crops to control boll weevils prior to the development of organic pesticides like DDT in the middle of the 20th century (Figure 2).
Figure 2.  Dusting cotton from"A is for arsenic" Wired 6/19/2012

Figure 3. "Arsenic and Old Railyards" F. Harrison
Along side sugar cane and livestock, cultivation of cotton provided an economically important income for Lafayette farmers since the earliest days of our town then named Vermilionville (Griffin, 1959).  Cotton farming has now come to an end in Lafayette Parish (Soil Survey of Lafayette Parish, LA, 1916Soil Survey of Lafayette Parish, LA, 1977NRCS Web Soil Survey, 2017), but in many places the legacy of arsenic pesticide use remains in our soil. Today in Acadiana, many sugar cane and rice fields cover the ground where cotton once grew, and the legacy of arsenic contaminates our rice crops (C. Poterra, 2007; B. Goodman, 2011;  T. Greenaway, 2012Consumer Reports, 2012). Recent spreading of suburban development on our former cotton fields may also lead to routine but unrecognized exposure of Acadiana families to arsenic.

Arsenic was also used routinely in railroad operations to preserve rail ties and other wood, and to kill weeds along the right-of-way (MADEP, undated) so that engineers had an unobstructed view ahead and along each side of the tracks. Planned "rails-to-trails" projects have been complicated or even blocked by by the discovery of elevated soil arsenic levels leading to unanticipated clean-up costs (Ciabotti et al, 2004). The Rails-to-Trails Conservancy has published a compilation of case studies and guidance related to understanding contamination issues (Ciabatti et al, 2004), and the State of Massachusetts has recognized that repurposing of abandoned railroad routes poses a risk, and have published guidance in the form of Best Management Practices (BMPs) for the development of rail-trails (Massachusetts DEP, undated).

The railroad was completed to Vermilionville in 1880, and today continues to run through our city which is now named Lafayette. The arrival of the railroad connecting New Orleans and Houston brought jobs, growth, prosperity, and commerce to our city. Steam trains which burned bunker oil had limited range, and all trains passing through Lafayette had to stop for refueling and to take on water and sand. The Lafayette railyard grew to be a major facility employing up to 1000 workers and providing complete maintenance service for the early steam engines (Griffin, 1959). There is now concern that the downtown railyard which was abandoned in the mid 1960s (Louisiana DOTD Draft Phase I ESA, 2016) will contaminate the Chicot Aquifer and our municipal water wells (C. Taylor, 2016).

Arsenic contamination of old railyards and rail lines has been found across the US. The abandoned Union Pacific Railroad Ashland site in Oregon is likely typical (Harrison, 2008). This railyard has similarities in age and past uses to the abandoned Lafayette yard, but the Ashland site is roughly half its size and poses little risk to water supply wells or local groundwater below the surficial level. The UPRR-Ashland site operated as a locomotive maintenance and refueling station from 1887 until 1986. Also, in contrast to Lafayette, the UPRR is actively working to remediate the Ashland site.

Figure x. Cultural Thoughts
Health impacts of arsenic - Despite the fact that arsenic has been used as a poison for centuries, the more subtle chronic health impacts from long-term exposure were often not recognized in the past, to the extent that low doses of arsenic were often used as a medicine or tonic (Wikipedia-Arsenic Poisoning History). It is now recognized that chronic exposure to arsenic can cause many ailments including thickening of the skin, darker skin, abdominal pain, diarrhea, heart disease, numbness, stroke, diabetes, chronic respiratory disease, and cancers of the skin, lung liver, and kidney. There is no evidence based treatment for chronic exposure; therefore, management must be focused on reducing exposure (Ratnaike, 2003).

Arsenic standards, levels, and limits - The USEPA sets standards for allowable concentration of contaminants in drinking water. These are called Maximum Contaminant Levels or simply MCLs. In setting an MCL, EPA first determines what concentration of contaminant would cause no health effect, and terms this concentration the Maximum Contaminant Level Goal or MCLG. In setting the MCL, EPA considers the cost and practicality of treatment weighed against the public health risk for the specific contaminant. The MCLG for arsenic is zero, meaning that there is no minimum concentration below which there is no health risk. In 2000, the EPA initially proposed an MCL of 5 ug/L (micrograms of AS per liter), but considered other levels of 3, 5, 10, and 20. After comments were received and reviewed, the final and current MCL for arsenic was set at 10 ug/L with an MCLG of zero.

In the US, public water suppliers are required to test for arsenic and meet standards after treatment. However, many private wells may be untested and can be a significant risk to adults and especially to children. The short 10-minute film In Small Doses: Arsenic gives useful background information on the risks from arsenic and discusses the risk of arsenic exposure from private wells in New England.

Beyond the concern for exposure to arsenic through rice which was mentioned above, other foods can be a pathway for exposure and risk. A 2012 study by Consumer Reports provides much useful information. The FDA does not currently regulate the amount of arsenic that can be present in our food. However, Dartmouth University's Children's Health web site recommends that we should: (1) limit rice consumption, choose white rather than brown rice (2) limit apple juice consumption, drink other juices, or skip drinking fruit juice (3) read labels because rice sweetener in the form of brown rice syrup is used in many foods. Dartmouth also recommended always rinsing rice before cooking, but recent research reported by the FDA shows that rinsing rice before cooking results in very little arsenic reduction, but does reduce some valuable nutrients. Gardening on arsenic contaminated soil can present concerns. The Washington State Cooperative Extension has published guidelines for gardening on lead and contaminated soils (F. Peryea, 1999). One simple recommendation is to carefully wash garden fruits and vegetables to remove all traces of soil before eating.

In addition to arsenic exposure from food and drinking water, exposure from breathing contaminated air must be limited. For employees, OSHA sets exposure limits based on an 8-hour average concentration of arsenic in air. OSHA sets the arsenic action level at 5 micrograms of AS per cubic meter of air. Personnel working on the abandoned railyard property and along the rail line should take care to limit their exposure to contaminated soil and dust. Lawn mowing and weed control, for example, may produce dust contaminated with arsenic and other soil contaminants. And, it follows that the public needs to be assured that they are protected from dust blowing from these sites through careful management of all activities on the sites which may create dust leaving the property boundaries.