Is it possible that the Louisiana DOTD would build an interstate without considering flood impacts?

By examining at some internet photos of last year's flooding you can see clearly that the answer is YES.

Here is a photo of flooding in Baton Rouge provided by Atmosphere Ariel to KTBS in August 2016.

And, from August 17, 2016, this is a photo of I-12 published by WDSU with an article titled "Walker mayor to sue state over I-12 construction."

An article in the Livingston Parish news states
The lawsuit says a 19-mile concrete barrier, from East Baton Rouge Parish to the Walker area in Livingston Parish is “acting as a man-made flood wall that interrupts the natural flow of surface waters.”

Is it possible that DOTD built these lane dividers without considering that they would act as a dam during heavy rain? It appears again that the answer is YES.

Now, the Louisiana DOTD wants to add large amounts of impervious surface in Lafayette by building the I-49 Con. Incredibly, the only mention of flood impacts in their Environmental Impact Statement is that they just plan to drain the roadway into local drainage or directly to the Vermilion. While they have taken decades to plan the I-49 Con, they have given the citizens of Lafayette nothing to gauge its flooding impacts. In past presentations, we have been told to trust them. We have been told that flooding analysis will be part of their final design. But, flood impact analysis should be a central part of the Environmental Impact Statement for public scrutiny and comment. Just ask the mayor of Walker how much he trusts DOTD's flood design expertise!

Proper flood mitigation would likely require construction of a large retention pond on land with an elevation above the highest historic flood height. Any private developer in our parish would be required to build retention/detention, but the DOTD is not constrained by local ordinances. I do not see any available large tract of land available within our urban center to accommodate the retention pond. Bypass alternatives to the east along the Teche Ridge, or west following the proposed LRX route would both have ample rural land available for such mitigation.

The most probable result of waiting until final I-49 Con design to consider flood mitigation is that there will be no flood mitigation.

The Chicot Aquifer "impermeable barrier assumption" has been questioned by geologists for decades.

Dennis Sullivan

This post reprints a comment by Dennis G. Sullivan which was submitted to the DOTD on January 23, 2016. The comment was also published online by the Sierra Club. As a retired well log analyst,  Dennis Sullivan is an expert in the interpretation of geological data. His comment is reprinted with permission. His post cites US Geological Survey research on the inadequacy of the Chicot Aquifer confining layer to protect the source of our Lafayette drinking water from contamination. His comments are now especially relevant since surface contaminants have been monitored in Lafayette's drinking water wells and citizen organizations are recommending that specific actions be taken by our parish leadership which include development of a wellhead protection program to protect the sole-source of our drinking water, the Chicot Aquifer. 

Thank-you DOTD for the opportunity to submit a comment into the record today.  I would like to begin by thanking you for the resources made available on the internet at your Connector website.  In the course my investigations there I found the following document particularly useful:  Water Resources Technical Report No. 73: Thickness of the Chicot Aquifer System Surficial Confining Unit and location of Shallow Sands, Southwestern Louisiana.  This is a study written by B. Pierre Sargent of the U.S. Geological Survey in 2004.  It appears to have been commissioned by DOTD.  In layman’s terms it’s a study of the surface clays that function to “seal” the top of our primary source of drinking water in Southwestern Louisiana, The Chicot Aquifer fresh water sand.  This paper gathers data from well logs and recorded well screen depths of registered water wells to estimate how thick the protective clays (called the surficial confining unit) are and how prevalent shallow sands might be within this stratum.  Among the things that I found interesting were the following quoted items:
“…interbedded sands are collectively known as the shallow sands of the Chicot Aquifer system.  The shallow sands occur irregularly throughout the confining unit and may be hydraulically connected to underlying sediments (Chicot).”  p. 1
“The impermeable barrier assumption has been reconsidered in recent years because of various incidents of subsurface contamination. Trudeau, 1994 p. 2, Hanor, 1993 showed that the effective vertical hydraulic conductivity of surficial clay at a hazardous waste disposal site in southeastern Louisiana was as much as four orders of magnitude higher than reported laboratory measurements of clay core samples taken from the site.  Hanor attributed the difference to the presence of minor sand beds and to secondary porosity and fracturing that occurred during deposition and aerial weathering of the clay beds.”  p. 2
“Although the thickness of the confining unit may be relatively uniform across large areas, interbedded sands of varied areal extent and thickness are present within the confining unit.  These sands are collectively known as the shallow sands of the Chicot aquifer system.”  P. 2
“Jones and others (1956) described two areas where the depth to major sand is less than 50 ft. thick.  One area is in southern Vernon and Rapides Parishes…and the other follows the course of the Vermilion River through Lafayette, St. Martin, and Vermilion Parishes.” p. 5
“An exception to the southward thickening (of the surficial confining unit – dgs) occurs in parts of Vermilion and Lafayette Parishes along the approximate route of the Vermilion River (fig. 1) where the confining unit thins to between 40 and 80 ft. thick (fig. 3).”  p. 9
“In Lafayette Parish, wells screened in shallow sands are at depths less than 50 ft. in the eastern and central parts of the parish…” p. 22
“This report provides a basis for collection of more detailed information about the transmissivity of the confining unit and the nature of the interconnection and relation between the confining unit and the deeper hydrogeological units of the aquifer.”  p. 4
A 2007 legal decision (No. 06-30570, Consolidated Companies, Inc. v. Union Pacific Railroad Co, et. al) has indicated that past railroad activities have allowed soils to become contaminated to varying depths including the 8 ft. and the 20 ft. levels in a substantial area of the planned footprint of the elevated Connector.
There is therefore reason, I believe, to exercise special caution in the construction of an elevated Connector through this area of known pollution.  Considering the Chicot Aquifer’s importance as the primary source of drinking water for the majority of the residents of the City of Lafayette and all residents of Southwestern Louisiana, I respectfully request that the construction requirements for the Connector be elevated above “industrial” to the highest standard of precaution in all construction activities involving sub surface excavation of any kind.  To do anything less would be foolhardy and potentially dangerous to the health and safety of the citizens of our city and state.


Sargent, B. Pierre (2004) Thickness of the Chicot Aquifer system surficial confining unit and location of shallow sands, Southwestern Louisiana. Louisiana Department of Transportation and Development in cooperation with the US Geological Survey, Water Resources Technical Report No. 73.

Public comment from 16 years ago documents our citizens' struggle against the I-49 Con

Click on letter to enlarge.
The following comment by Kelly Roberts Caldwell dated April 30, 2001 was included in the FEIS, Volume II, page 299.  

Today, citizens continue to "battle a proposal that is, on its face, senseless." Now the senseless plan is called the I-49 Con.  

Secretary Kam Movassaghi
Department of Transportation & Development
P.O. Box 94245
Baton Rouge, LA 70804
Dear Sir:

The citizens of Lafayette fully support the extension of I-49 South. We strongly support a
Lafayette eastern bypass and are deeply opposed to an elevated interstate thru the heart of
our city. In July, 1992, a public meeting was held after an EIS was distributed of the Evangeline
Thruway corridor plan. Citizens voiced overwhelming opposition resulting in its withdrawal. In
1997, the project was restarted by DOTD at the urging of the chamber of Commerce leadership
who have relentlessly pursued the Evangeline Thruway placement. New strategy! Lead the
public to believe that other alternatives are being considered. Many reasonably assumed that the
1992 official public rejection eliminated Evangeline Thruway. Wrong! Residents realized very
late thai the "alternatives" were all simply "variations" of the previously rejected Thruway plan.

I am a spokesperson for a campaign by The Sierra Club, Citizens Speak Out, Sterling Grove
Historic Association, Tree Society of Acadiana, Annabelle Subdivision Association, and others
joined to promote an I-49 eastern bypass. Our petition has over 1000 signatures with more added
each day. Lafayette citizens arc now at risk from the 50,000 vehicles per day on Evangeline
Thruway, many hauling hazardous materials. Why plan to increase the risk with 100,000 daily
estimated for completed I-49? Proponents insist an eastern bypass was studied and rejected.
Rejected by whom? Where are the studies? Why choose this destruction and danger to our
community? ls it simply a price the local power structure is willing to pay to keep the project all
within Lafayette Parish - avoid sharing with our neighbor, St. Martin?

We are told a Lafayette eastern bypass would impact wetlands (though their plan requires moving
a runway at our airport into wetlands). Harold Schoeffler, a well known businessman and
environmentalist and Pierce Meleton, respected architect, and others actually mapped out a route
to the east between Breaux Bridge and Lafayette into St. Martin. It runs beyond Cypress Island
Swamp but west of the beautiful Teche thru sugar cane fields and pasture land coming back into
90 below Broussard. Destroys no homes or businesses. Gives St. Martin needed interstate
access and avoids the adverse impacts in Lafayette. Be vastly superior for evacuation- with two
highways out rather than the one sure to become an elevated trap in Lafayette. When taken to
highway engineers cost estimates were about half that of cutting thru lafayette. Likely you were
sent the St. Martin resolution asking that the Teche Ridge alternative be considered.

Citizens must battle to save themselves from a proposal that is, on its face, senseless? Impacts
to the human and natural environment so enormous that governments' talk of "mitigation" is a
joke in the community. An elevated federal interstate alongside a national historic district?
Elderly, poor and minorities disproportionately impacted? Their sector of the city walled of!?
Please do what you can.

Kelly Roberts Caldwell

A manufactured gas plant in Lafayette? And why Lafayette needs a drinking water protection program?

You know the idiom "carrying coals to Newcastle." It refers to taking something to a place where it already exists in abundance. It seems that this would apply to manufacturing gas from coal and/or oil in Louisiana, so let me explain.
By 1900, Lafayette's residents had both water and electricity as residential utilities. However, in the early 1920's there was still no natural gas pipeline carrying gas to Lafayette, and no residential or industrial gas utility available. To respond to this demand, the Louisiana Public Service Company built a manufactured gas plant and ran pipes to service Lafayette residences in 1926 (Griffin, 1959).  The gas plant was located north of the railyard (Figure 1). In 1931, a natural gas pipeline reached Lafayette from Northern Louisiana, and operation of the manufactured gas plant was discontinued.

While this history is interesting, you may be wondering "how is a former manufactured gas plant site related to the I-49 Connector issues?" It is another likely source of contamination endangering the Chicot Aquifer which is designated as the sole-source of drinking water for Lafayette Parish. Before we design or construct this interstate over our water wells and sites of contamination we need to quantify the threat and plan how to deal with it for ourselves and our children.

Figure 1. Louisiana Public Utilities Company gas plant as mapped in 1928 (clipped from 1928 Sanborn map of Lafayette, Louisiana from electronic copy available through the Lafayette Public Library).

Figure 2. Contemporary view of the LPUC former gas plant location (red oval) mapped by Google Earth (saved on April 10, 2017). The LUS North Water Treatment Plant (blue rectangle) and LUS water well #16 (small blue oval) are also highlighted.
Throughout North America, high levels of soil and groundwater contamination have been discovered at former manufactured gas plant (FMGP) sites. The USEPA has listed former manufactured gas sites in its priority site list (, undated), and this includes a site in Lake Charles, Louisiana (page 1004, Hathaway, A.W., 2011). Significant quantities of waste "tar" was produced during the gas manufacturing process, and this waste was often simply disposed of on-site in open pits. Waste products created by the manufacturing process that are now associated with FMGP sites include (Heritage Research Center, 2007):

2-methylnapthalene, Acenaphthylene, Ancenapthene, Anthracene, Arsenic., Benzene, Benzo(a)anthracene, Benzo(a)pyrene, Benzo(b)fluoranthene, Benzo(k)fluoranthene, Chromium, Chrysene, Cyanide, Dibenzo(a,h)anthracene, Dibenzofuran, Ethylbenzene, Fluoranthene, Fluorene, Indeno(1,2,3-cd)pyrene, Lead, Methylphenol, Napthalene, Phenanthrene, Phenols, Polynuclear / Polycyclical Aromatic Hydrocarbons (PAHs), Pyrene, Semi-Volatile Organic Compounds (SVOCs), Toluene, Volatile Organic Compounds (VOCs), Xylenes
The proximity of the FMGP site to our Lafayette drinking water wells (Figure 2) heightens the already existing  concern over contamination of our Chicot Aquifer. Monitoring has already clearly established that surface contaminants are finding their way into our wells (Connector Comments, 2017a, and 2017b).

In a letter proposing recommended actions to our local political leadership, the Acadiana Group of the Sierra Club and the WaterMark Alliance recommendation #10 was to draft and adopt ordinances based on LDEQ drinking water protection sample ordinances. The presence of yet another risk to our drinking water further demonstrates the need for a Lafayette drinking water protection plan, an ongoing program, and protective ordinances. The Chicot Aquifer beneath Lafayette is a plentiful source of water, but its quality can be compromised for present and future generations if we fail to protect it.


Connector Comments (2017a). Y-49 takes a turn: Public meeting summary and video, January 19, 2017. published 1/29/2017.

Connector Comments (2017b). Contamination of our Chicot Aquifer.  What do we know? How do we know? What should be done? published 4/3/2017.

Hathaway, Allen W. (2011). Remediation of Former Manufactured Gas Plants and Other Coal-Tar Sites. CRC Press, 1398 pages., (undated) Former Manufactured Gas Plants. accessed April 2017.

Heritage Research Center (2007) Manufactured Gas - The Genie’s Legacy

Contamination of our Chicot Aquifer: April 3, 2017, CCGG Meeting

The Concerned Citizens for Good Government (CCGG) held its regular 1st meeting of the month on Monday, April 3, 2017 at Alesi’s Pizza House in Lafayette, LA.  Guest speaker was Michael Waldon, PhD, and retired licensed professional environmental engineer. The title of the presentation was: Contamination of our Chicot Aquifer.  What do we know? How do we know? What should be done? WaterMark Alliance spokesperson Kim Goodell also gave an update to pending litigation and the I-49 Project. As always, there was an opportunity to ask pertinent questions at the end of the presentation.

If you missed the meeting, you can still participate. Click the following links to learn more about the meeting"

Additionally, you can still participate by sharing to Facebook or other media using the share buttons below, and by adding your ideas and questions in the comments section. If you feel strongly about the issue, please contact our political leaders. Our local leaders' contact information is available by clicking HERE.

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.
Page 1

Page 2

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

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.

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.

Y-49 takes a turn: Public meeting summary and video, January 19, 2017

This post compiles information from the Y-49 public meeting held on January 19, 2017 at the Lafayette Public Library. Roughly 100 citizens attended this meeting. Video of the meeting was produced by the Acadiana Open Channel (AOC), and the full two hour meeting video is available through YouTube.

In the summary that follows, direct links to the beginning of each speaker's presentation are provided for your convenience.
Meeting announcement.

Woody Martin welcomed the public on behalf of the Acadiana Group of the Sierra Club, and provided introductions of the evening's speakers.

Bill Goodell has been an environmental attorney for over 30 years. He shared some of the results of his investigations into contamination from the abandoned Union Pacific Railyard in downtown Lafayette, which sits above the Chicot Aquifer, Lafayette's drinking water source. His information came primarily from publicly available records. Goodell focused attention on p-dichlorobenzene (p-DCB or simply DCB) which has been monitored for several years in LUS water wells beneath the railyard. DCB does not occur naturally; it must originate at the surface. Because DCB is one of many known contaminants at the abandoned site the legal presumption is that the contamination originates from the contaminated railyard site. In 1974, the Louisiana constitution required conservation of our environmental resources and protection of the public. Public bodies have a duty to uphold this constitutional requirement, referred to as the public trust doctrine.

Kim Goodell leads the local WaterMark organization. She provided a history of citizen opposition to the I-49 Connector project and discussed the need for our political leaders to integrate the public trust doctrine into their actions. She stated that because of the public trust doctrine our local and state officials are expected to not simply be reactive, but be proactive in protecting the public from risks like drinking water contamination. Why have our local officials been less than aggressive in carrying out their constitutional duty?

Michael Waldon, PhD, is a retired from a career as an environmental engineer, hydrologist, and professor at LSU and UL-Lafayette. Dr. Waldon described the Louisiana DOTD Phase I Environmental Site Assessment (ESA) of contamination within the footprint of the proposed I-49 Connector. This includes the heavily contaminated railyard. Of the 195 properties in the footprint of the I-49 project, DOTD consultants recommend that 24 properties including the railyard need further evaluation. Although a year old, this study has not been publicly released for review, and was obtained only through a Freedom of Information Act disclosure. While we agree with the recommendation that more study is needed, the report has numerous deficiencies and failed to report important publicly available information. The report failed to discover monitoring data that show that surface contamination has reached Lafayette's water wells.

Harold Schoeffler is a leader with the Sierra Club and other civic organizations. Mr Schoeffler gave a brief history of the railroad in Lafayette. The Sabine was the first steam engine to arrive in Lafayette in 1875. Since the later 1800's the Lafayette railyard was a site for trains to take on water, sand, and fuel. Lafayette was also a major site for engine maintenance. The roundhouse, constructed in 1882, serviced steam engines for many decades. Maintenance often involved washing trains with the organic solvent trichloroethane (TCE), and removal of asbestos which was disposed of in ponds on-site. Every form of waste was dumped into the disposal ponds. The roundhouse operated until 1962. The railyard at times employed over one thousand people, and was a major source of employment in Lafayette. Mr. Schoeffler concludes that the railyard should have been cleaned up in the 1960s when it was closed. Today the wastes remain and the abandoned site still needs to be cleaned up.

Public comments and questions were solicited. Questions included what quantitative information is available and whether any political leaders or government employees were in attendance. The geographic extent of the impact was also discussed. Commenters suggested that attendees express their concern to our local political leaders. People were concerned about the status of compliance with Louisiana DEQ and US EPA requirements - were these agencies protecting the public? Finally, the US EPA EJScreen environmental and social justice mapping tool was suggested as a useful source for comparing the railroad site with other sites across the US.

Other links related to the meeting:
Article by Wynce Nolley, The Independent, January 20, 2017.  "Sierra Club: contamination in LUS water supply"

Article by Kendra Chamberlain, Louisiana Uncovered, January 27, 2017. "Lafayette citizens meet over concerns about alleged water well contamination - While city council members are MIA"

Dr. Waldon's slide presentation is separately available through

The current LUS drinking water quality summary report is available for download at

Airport angles and increased risk

SUMMARY: Because this is an unusually long post, you may wish to skip first to the SUMMARY at the end of this post before reading the entire post.

A LOT has been written on the topic of "things you just should never do."  One of these "never do" actions is to build tall structures next to your airport. This is precisely the DOTD plan for extending I-49 through Lafayette.

In an earlier post I talked in general about the problems associated with the Connector plans relative to the Lafayette Airport. In this post. I want to get down to specifics.

Figure 1.  Google Earth image of the northwest end of runway 11-29 in relation to the intersection of Evangeline Thruway, University Ave, and Surrey St.  

Federal safety guidance defines the maximum height that objects should not exceed in the vicinity of airports. This definition is based on a number of imaginary surfaces through which no objects sitting on the ground should penetrate. Keeping aircraft above the imaginary surfaces, and all terrestrial objects below, provides for safe landings and takeoffs.

The lowest of these imaginary surfaces, the primary surface, is a rectangle at the elevation of the runway. The primary surface extends 200 feet beyond each end of the runway and 500 feet on each side of the runway centerline. Beyond each end of the primary surface there is an approach surface. The approach surface begins at the primary surface elevation and rises, for runway 11-29, at a slope of 34:1 (termed a 3% slope). That is, for every 34 feet of center-line distance the surface rises 1 foot.  At their intersection, the width of the approach surface is the same as the primary surface, 1000 feet, and is centered on the runway center-line. The approach surface widens to 4000 feet at 10,000 feet ground distance from the primary surface. That is, the approach surface width is 1000+0.3x, where x is the ground distance along the center-line away from the primary surface. There are other defined surfaces (transitional surface, horizontal surface, conical surface), but only the primary and approach surfaces are relevant to the issue of runway displacement for 11-29.

The 2002 Final EIS asserts in numerous locations that the Lafayette Regional Airport runway 11-29 will need to be displaced 350 feet to the southeast toward Bayou Tortue and Cypress Island Swamp from its present location to meet minimum federal safety requirements for an approach surface slope of 34:1 and a 17 foot margin of safety (FEIS exhibit 4-4). While the FEIS makes the assertion that the 350 foot displacement is required, it does not show the underlying data or rationale needed to support the claim. I have therefore been forced to attempt to recreate these calculations. My calculations, however, do not agree with the conclusion in the FEIS. Lacking documentation of the FEIS methods, I conclude that the 350 foot assertion is likely in error.

A history and general information about the Lafayette Regional airport may be found in the Wikipedia article titled "Lafayette Regional Airport." Additional information on the airport That web page also includes a link to a useful Airport Diagram. The diagram shows that runway 11-29 is 5401 feet long and 148 feet wide. Elevation at the northeastern end (designated 11) is 37 feet; elevation at the southeastern end (designated 29) is 35 feet.

Figure 1 is an image captured from Google Earth of the northwest end (designation 11) of runway 11-29. It illustrates that the runway does end quite close to the current highway. Measurement shows that the runway currently ends roughly 600 feet from Evangeline Thruway (Hwy 90), and roughly 700 feet from the intersection of the Evangeline Thruway, Surrey St, and University Ave.

Figure 2. This image is extracted from the FEIS Plate 2a2. North in this figure is to the right, and distance along the horizontal extent of the roadway in hundreds of feet is given on the horizontal axis; elevation in feet (NGVD 29 datum) is plotted on the vertical axis. The roadway is charted as the solid black line. The 40 foot elevation is highlighted by a dotted red line. Peak roadway height at the interchange is estimated to be 45 feet. 

Finally, it is necessary to estimate the height of objects above the roadway. This could include signs, streetlights, and aircraft warning lights. The FEIS does mention this, and suggests that special signage and lighting may be necessary. Thus, I will assume that the height of the vehicles on the roadway will be the tallest objects above the roadway. There is no Federal vehicle height requirement for commercial motor vehicles (CMVs). Most eastern states, including Louisiana, set a CMV height limit of 13.5 feet on most highways. Louisiana does allow heights of 14 feet on designated highways, and oversize permits can be routinely issued for heights up to 16 feet 5 inches. Without specific guidance from the Louisiana DOTD, it is unclear what height should be assumed. Here, I will simply assume a maximum height of 15 feet for all vehicles and objects on the roadway.

Assuming the peak height at the interchange structure controls the required runway displacement, the calculation of length for the approach surface is now straightforward.  The interchange height plus object height has an elevation of 60 feet (45+15). Adding the FAA 17 foot margin of safety gives a total elevation of 77 feet. Subtracting the runway height which defines the primary surface elevation then gives a height of 40 feet (77-37). At a slope of 34:1, the length of the approach surface to the primary surface is 1,360 feet (34x40). At this point along the approach surface, the approach surface width is 1408 feet (1000 + 0.3x1,360), or 704 feet on each side of the extended runway center-line (Figure 3). Adding the 200 foot width of the primary surface at the end of the runway gives a total distance form the peak of the interchange of 1,560 feet. The present distance is estimated to be 700 feet, so the total runway displacement required would be 860 feet (Figure 4). This is 510 feet longer than the value asserted in the FEIS. This difference significantly brings into question the economic, environmental, and engineering feasibility of the displacement.

Figure 3. The more northern half of the new approach surface (black outlined trapezoid) begins with a width which is 500 feet on either side of the extended runway centerline, and 200 feet beyond the new runway end (orange line). The distance to the centerline extends to 704 feet at the proposed elevated interchange.

The calculated extension will require very roughly the destruction of 45 acres of the Cypress Island Swamp west of the airport (Figure 4), and more if embankments in the swamp must be longer than existing embankments. This considerably exceeds the 5 acres estimated in the FEIS (p 4-92).


Figure 4. The upper figure (a) shows the current airport runway at the southeast end of runway 11-29. The lower figure (b) is the same image with an 860 foot length of runway and associated area is copied onto the current end of the runway. The original image was printed from Google Earth. 
Construction would require significant fill, and consolidation of the underlying wetland soil will further aggravate the existing problems of soil stability at this end of runway 11-29.  The FEIS on page 2-10 states that "a prior runway extension of about 200' constructed in 1967 has subsided up to approximately four feet and has been removed from service." This fill will encounter even greater engineering challenges.

The new extension into the swamp will need to deal with a very significant drop in elevation (Figure 5). As much as 35 feet of fill will be required for the extension. If earthen embankments are used at the sides of the filled area, considerably more than the estimated 35 acre area of wetland may be required in order to accommodate the more extensive embankment areas.

Figure 5. In (a), the center line of the runway (red line) is extended at the southwest end of runway 11-29. The green bar indicates 860 feet from the end of the center line, and the thin white lie crossing the center line is 860 feet from the runway end. Figure (b) graphs elevation along the center line from 39 ft to 4 ft.  

Options: What are our options? They include:
  1. The No Build alternative should always be considered. If the currently planned I-49 Connector project is abandoned, it could be replaced by upgrades to the current Evangeline Thruway, and bypass to the east along the Teche-Ridge, west using the LRX alignment, or both to form an urban loop.
  2. Build the connector project as decided in the FEIS and ROD, and extend runway 11-29 as required to meet minimum FAA guidelines. This will require land acquisition and a Corps of Engineers wetland permit. Likely this alternative will further require wetland mitigation and flood mitigation.
  3. Build the connector project as decided in the FEIS and ROD, and request an FAA exemption from airport approach obstacle safety requirements.
  4. Abandon use of runway 11-29.
  5. Revise the design in of the selected alternative to eliminate roadway elevation in the vicinity of the 11-29 runway approach surface.

SUMMARY: The I-49 Connector FEIS identified unacceptable risk due to failure to meet FAA flight path obstruction guidance, resulting from the proposed interchange construction adjacent to the Lafayette Regional Airport. Without documenting calculations or rationale, the FEIS stated that in order to meet these minimum safety requirements, airport runway 11-29 would need to be displaced 350 feet southeast toward Bayou Tortue and the Cypress Island Swamp.

My calculations, based on FAA guidance, arrive at runway displacement considerably longer than that presented in the FEIS. Here, following FAA guidance, I calculated that the required displacement is 860 feet. This significant difference brings into question the economic, environmental, and engineering feasibility of the displacement. Impact of this displacement on flooding, wildlife, and wetlands should be carefully addressed and documented by DOTD.

The public attitude toward airport safety should always be conservative and circumspect. The Airport's 1975 Master Plan concludes "Conditions at the airport's periphery make expansion of its land area difficult or expensive or both." Even beyond the impacts of runway displacement discussed above, it is simply inappropriate to choose to construct any tall structures on the periphery of our airport which is already severely constrained at its location. Tall structures like the University and Kaliste Saloom interchanges constrain future airport runway alignment adjustments, and impact the ability to meet current requirements and future safety requirements should FAA guidance on safety margins or approach slopes change for any reason.