Mining BMPs Could Help Reduce Toxicity of Floodwaters

This is the sixth in a series on Sand Mining Best Management Practices (BMPs) proposed by the Texas Commission on Environmental Quality (TCEQ). BMPs help reduce erosion and prevent pollution, but these don’t address some important issues.

Strengthening them could reduce both the magnitude and toxicity of future floods. By reducing the amount of excess sediment that enters the river, we can help reduce blockages that contribute to flooding. And by better managing fuels, we can help reduce the toxicity of stormwater runoff.

Public comments are due by August 19, 2021.

Equipment at West Fork mine separating sand and gravel.

Sixth in Series

The five previous posts have talked about:

Mining Phase

This post will focus on the actual mining phase. For brevity, I will summarize the BMPs. But here is a link to the exact proposed text. I will also provide suggestions for improvement at the end of this post for those committed individuals still with me.

Large parts of this section describe the mining process. Some have no BMPs. I have summarized the process and tried to condense the BMPs for readability.

As we saw in the post about setbacks, simply having the setback requirement is no guarantee operators will observe it. Likewise with some of these BMPs.

I never really thought about fuel storage at a sand mine until I read these BMPs. Then I reviewed by pictures and found that few mines would comply with these proposed rules.

4.1       Dredging Activities

After stripping away overburden, dredging begins. Suction and pumping send sand and other materials to a wash plant where they are separated using a sizing screen. Water generated during the pumping process can flow back into the pit. Sand is separated from gravel and stockpiled or sent to the pit via a sand flume. Sized aggregate is stockpiled onsite until sale.

4.2       Aggregate Wash Plant Area (Wet Processing)

Process wastewater results from the production, clean-up, or use of any raw material, intermediate product, finished product, byproduct, or waste product. Treatment of wastewater before discharge to alter its characteristics is often required to achieve compliance. Examples of treatment include pH adjustment and removal of solids through either physical or chemical means prior to discharge to surface water.

BMPs required during this portion of the mining process include proper berming and/or ditching of pump water from the dredge to the wash plant and back into the open pit.

Pump water flows back into the pit to avoid unpermitted process water from escaping.

Runoff from the stockpiles must be routed to the open pit. Rainfall runoff from stockpiles must also go to the pit.

Other BMPs include silt fencing, berms, and vegetated buffers to ensure runoff from stockpiles is controlled.

4.3       Aggregate Processing Plant Area (Dry Processing)

Some sand used for fill, bedding, etc. does not require processing, but most does. Processing for specific markets involves the use of different combinations of washers, screens, and classifiers to segregate particle sizes.

After transport to the processing plant, the wet sand (raw feed) is transported to fixed or vibrating scalping screens that separate particle sizes. Oversize material may be directed to a crusher for size reduction to produce manufactured sand. Following crushing, material returns to the screening operation for additional sizing.

Alternatively, oversize material (greater than two inches) may be used for erosion control, reclamation, or other uses.

During screening, water sprayed onto material removes clays and other deleterious material.

After classification, sand is dewatered, then conveyed to storage bins or stockpiles.

4.4       Maintenance Area(s)

Controlling contamination of stormwater is critical. Stormwater quickly picks up pollutants from improperly stored materials or spills.

Train employees to cover toxic materials, channel stormwater, and perform preventative maintenance to reduce pollutant-laden stormwater.

A Spill Prevention Control & Countermeasures (SPCC) Plan must be in place to implement spill prevention and response. Ongoing inspection assures that site management is having the desired effect.

Locate fuel/oil storage/handling facilities away from the main sediment and wash-water retention facility.

Equip all such facilities with approved containment, monitoring, and collection systems.

No containment system here. No runoff provisions. Note rusting 55 gallon drum.

Store fuel above ground.

Route runoff from adjacent surfaces to a retention pond that can be cleaned after a spill.

4.5       Petroleum Product Storage and Handling Area

1.  Regulatory Requirements

Operators must comply with all local, state, and federal requirements for petroleum storage tanks.

TCEQ requires registration of petroleum storage tanks.

EPA requires a written Spill Prevention, Control, and Countermeasure Plan for any facility that stores more than 1,320 gallons in containers 55 gallons or greater.

2. BMPs

Many BMPs address proper storage, handling, and transfer of petroleum products. Some of the more important BMPs include:

  • Signs must be posted instructing drivers to remain with their vehicles at all times to prevent overfill spillage.
  • Fuel delivery drivers must be chock wheels or lock brakes prior to offloading fuel, and ensure all hoses are disconnected prior to departure.
  • All fuel transfer areas must have secondary containment large enough to handle the largest single compartment of any tank truck in the facility. Alternatively, discharged material must be directed to a containment pond through the use of berms and swales.
  • Use drip pans or buckets at disconnection points of hoses and/or piping to collect drippage of oil.
  • Inspect all storage tanks once per month for signs of fatigue or failure that could lead to the spillage. Document these inspections. Promptly repair any leaking, corroded, or deteriorated tanks that could discharge oil.
  • Examine all pollution prevention equipment once per month to ensure it is in good operating condition. Fill out and keep onsite the monthly report.
  • Build secondary containment structures around all bulk oil and lubricant storage tanks. They must have sufficient capacity to contain any spills caused by rupture of the tank.
No containment structures.
  • All secondary containment structures must have 110 percent of the capacity of the largest storage tank and must be constructed of material impervious to tank contents.
Fuel stored out in open with no containment structure.
  • Containment structures must have manually operated gate valves to drain rainwater. Alternatively, keep a portable pump available to drain the containment area. All manually operated valves must be locked closed when not in use.
  • Inspect accumulated rainwater prior to discharge to ensure that there is no petroleum sheen on it. Water with a sheen must never be discharged. It may be pumped for disposal, allowed to evaporate, or removed by some other appropriate method. TCEQ requires documentation the visual inspection.

Oil Discharge Response and Cleanup

When an oil discharge happens within the plant area, all manpower and equipment available must be utilized to prevent the discharge from reaching a navigable waterway. Stop the discharge. Control its impact to the environment.

Procedure after a discharge:

  • The first person to notice the discharge must immediately notify the plant superintendent; the superintendent, in turn, must simultaneously implement best management practices to capture the discharge.
  • Depending on the volume of the spill, the operator is required to notify TCEQ immediately, or at least within 24 hours. Operators must refer to 30 TAC Chapter 327 for complete rules and regulations regarding spills.
  • If possible, prevent further leakage by plug sources and/or closing valves.
  • A front-end loader must be immediately available to build a berm or dike with dry sand to absorb the discharge if the secondary containment should fail.
  • In the event of a discharge on the concrete in the shop or other hard surface, the following procedure must be used:
    • Absorbents must be used to keep the discharge from leaving the hard surface.
    • Identify the source of the discharge and fix the leak by whatever means necessary.
    • Place used absorbent in a drum (labeled with USED ABSORBENT, NON-HAZARDOUS). The drum must have a lid, which is kept on at all times when not in use. The drum must have the first date the used absorbent was placed in the drum. Keep drums under a roofed structure to prevent stormwater contamination.
  • If any discharged material has left the impervious surface, the media contaminated from the discharge must be properly removed and disposed of in accordance with all applicable local, state, and federal environmental regulations.
  • If the discharge is too large for plant personnel to contain, employ a contractor.

After the leak is repaired, the discharged product must be recovered from the secondary containment and appropriately managed in accordance with current state and federal regulations. If sand or surface soils are contaminated, dispose of them in accordance with current state and federal regulations.

Rehak’s Take

These BMPs address fuel management more than mining. In my opinion, both sections are good as far as they go. But I would like to see at least some BMPs added based on observations of actual practices.

Under dredging:

Operators should not dredge a vertical wall at the edge of buffer zones. This can lead to cave ins at the edges that decrease the width of the buffer zones.

Dredging next to buffer zone can cause cave-ins that reduce buffer’s width, especially when the pond wall is deep and steep. More slope would reduce the chances of buffer collapse.

Under fuel management:

Fuel depots and fuel storage tanks must be located outside of the floodway, on the highest ground possible and as far from rivers as possible. Make sure the location meets Atlas-14 requirements.

Rusting fuel storage tanks in floodway without covers or containment structures. When Atlas 14 maps are released next year, this area will be even further into the floodway.

And two more:

Remove all fuel storage equipment and tanks before abandoning a mine.

Abandoned equipment on East Fork mine has since been removed after a complaint to the TCEQ.

Finally, do not store excavation equipment underwater.

This piece of equipment has been abandoned in this mine for years.

To Submit Public Comments

Please submit your thoughts on Mining and other BMPs to the TCEQ. Email Macayla.Coleman@Tceq.Texas.gov with the subject line “BMPs Guidance Document” before August 19, 2021.

Posted by Bob Rehak on 8/15/2021

1447 Days since Hurricane Harvey

The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.

BMPs for Pre-Mining Phase of Sand Mining Can Help Prevent Erosion that Contributes to Flooding

According to best management practices (BMPs) being proposed by the TCEQ, pre-mining planning is one of the main ways to prevent sediment from leaving a mine.

So much sand piled up in the San Jacinto after Hurricane Harvey that it reduced the conveyance of the river, contributed to flooding, and cost hundreds of millions of dollars to remove.

I consider good sand mining operations so important to the reduction of future flooding that I am publishing a series of articles on these proposed BMPs. This is the fifth. The first provided an overview. Then, I discussed:

This post will discuss BMPs for pre-mining and provide a list of suggestions for public comment at the end.

Life on the edge. Expansion of a West Fork sand mine right up the edge of the river’s cut bank. That will make this future mine especially susceptible to river migration and pit capture. It is probably not a good idea to mine this close to this part of the river. Bad pre-planning!

Pre-Mining

For brevity, I’ll summarize each of the pre-mining BMPs. To see exact text being proposed by the TCEQ, click here.

3.1       Site Evaluation

Miners must begin by evaluating a site for how mining will take place and what will happen to the mine when it closes. This is typically called a Mine Plan and includes:

  • Location of processing plant, office, support facilities, roads, product staging areas, and overburden placement.
  • An evaluation of the soil type(s) in the area planned for mining.

Susceptibility of these soils to erosion must be known when planning. Sands, silts and clays act differently when worked by earthmoving equipment.

3.2       Understanding Site Drainage

It is important to know pre-existing drainage patterns and where concentrated flows want to exit a site. This will determine the selection of structural control BMPs, such as culverts, to minimize adverse impacts.

3.2.1    Surface Water Flow

Identifying the receiving waters (i.e., Lake Houston, the San Jacinto, Spring Creek, Caney Creek, White Oak Creek) is vital before site preparation starts. Operators must determine all appropriate agencies with jurisdiction over the receiving waters. The TCEQ and USEPA Region 6 continuously develop Total Maximum Daily Loads (TMDLs) for water bodies not meeting their designated uses.

If the TMDL has already been developed, it may not allow additional inputs (discharges) to the receiving stream. Therefore, it is important to know which water bodies have had TMDLs developed for them or are scheduled for TMDLs. This information can also be found on the TCEQ’s Index of Water Quality Impairments.

Inspection during or after a rainfall event can provide a substantial amount of information regarding how surface water flows.

3.2.2    Ground Water Conditions

Understand that mining of a potable aquifer can negatively affect the yield of a potable well.

The following BMPs will help guide a ground water preservation effort:

  • When a new sand and gravel operation is being considered, operators must first check the Texas Water Development Board water well reports data and the TCEQ water well report viewer to determine if registered public and private drinking water supply wells are located nearby.
  • Perform a visual check for possible unregistered private wells or abandoned wells in the immediate vicinity of the new sand and gravel pit. If an unregistered private well or abandoned well is discovered, operators must refer to TCEQ’s Regulatory Guidance Landowner’s Guide to Plugging Abandoned Water Wells (RG-347) for more information on the necessary actions which must be taken.
3.3       Site Preparation

Only after surface water drainage and ground water conditions are thoroughly understood may site preparation be initiated.

Once initiated, operators must inspect disturbed areas (cleared, graded, or excavated) of the site at least once every seven (7) calendar days for signs of visible erosion.

3.3.1    Construction of Access and Haul Roads

Roads are a necessary component of any sand and gravel mining operation, especially on large pieces of property. Operators must take care to minimize impacts to the environment when constructing roads.

Roads must be designed to drain at all times by using crowning, graveling, compacting, ditching, and/or culverting

Proper construction and maintenance should minimize erosion by rainfall runoff, dust, and normal vehicle use. Where necessary, road surfaces must be graveled if the base does not already contain sufficient aggregate.

Crowning of Roads

Surfaces must be crowned to minimize erosion of the roadbed.

Graveling and Compacting

Graveling and compacting of road surfaces require less maintenance. It minimizes loose sediment runoff or tracking of sediment onto public roads.

Ditching and Culverting

Ditches and culverts carry runoff alongside or underneath a roadbed. They must be:

  • Sized for anticipated rainfall events.
  • Installed at the time of roadway construction
  • Sloped to prevent silting and allow for maintenance (i.e., digging out sediment buildup).
  • Kept free of debris and obstructions.

Typically, ditches can be used for routing surface water flow away from adjacent properties offsite.

Silt Fencing

Silt fencing can aid in soil erosion caused by surface runoff from roadways. The bottom must be secured beneath the ground surface to prevent under-washing.

3.3.2    Land Clearing and Grubbing Activities

Land clearing and grubbing involves removing all trees, stumps, roots and other debris from the site. It may also include removal and disposal of old, unwanted structures. Proper disposal will be discussed in a later post.

Disturb only those areas ready for immediate use. Install sediment holding basins before major site grading. They can catch and hold surface runoff before it leaves the site.

Divert upslope water around an area planned for disturbance.

Plan clearing and grubbing activities for a time of year that minimizes the impact of inclement weather on disturbed areas.

Temporarily stabilize or cover disturbed areas to minimize impacts on the environment.

Operators must only clear and grub acreage needed for activities occurring before the next anticipated storm event.

Clearing or grubbing too much land too early in construction dramatically increases the potential for surface water runoff and the costs to control it.

Operators must schedule grading to protect disturbed areas from stormwater runoff.

A minimum 100-foot buffer zone is required adjacent to perennial streams and water bodies in the State of Texas.

3.3.3    Stripping Activities

“Stripping” describes the removal of overburden on top of valuable sand reserves. Overburden is typically clay, silt, and fine sand. Operators may stockpile these materials for post-mining restoration. But the BMPs also allow disposal by placing them into a pit no longer being used.

Operators must control runoff from stockpiles.

Stockpiles should be located away from concentrated flows of storm water, drainage courses, and inlets, and protected with perimeter sediment barriers.

Operators should be able to effectively control runoff from any areas they disturb. So they should be careful not to strip too large of an area all at once. Stripping to large of an area contributes to excessive buildup of silt or clay in ditches.

Normally, operators will direct surface water to pits to keep the water table high in extended periods of dry weather.

Operators must leave enough undisturbed buffer at property boundaries to provide sufficient lateral support of property lines as determined by the licensed professional engineer or geoscientist certifying BMPs at the site.

Concerns

While I applaud what the TCEQ is trying to do, I still have concerns with several BMPs listed above and plan to make public comments on them.

Section 3.1 – Site Evaluation

This section requires a mine plan, but not approval of the plan. The plan should be approved by the TCEQ.

Most of the mines are at least partially in FEMA defined floodways. But this section makes no mention of that. Hydrologic and hydraulic analyses should be performed by competent and reputable third-party engineers to show that no part of the mine will increase flood levels or erosion upstream, downstream, or to adjoining properties.

FEMA Flood Map shows most Lake Houston Area sand mines are at least partially in floodways (cross-hatched areas).

Section 3.2.1 – Surface Water Flow

Additional erosion controls or increased buffer widths may be needed where river erosion rates are high,

Also, the East Fork, West Fork, Caney Creek, White Oak Creek, Spring Creek and Lake Houston already are listed as impaired. Impairments have to do mostly with bacteria, PCB, and/or dioxin levels. All of the above already have Total Maximum Daily Loads or are scheduled to implement TMDLs soon.

I suspect the TCEQ permits some discharges from sand mines and postpones others to keep the streams under the TMDL limit. But I have also seen many TCEQ reports about un-permitted discharges. I have seen breaches in dikes remain open for months and years. I have seen rivers capture pits during storms.

The West Fork already has a bacteria problem from the Lake Conroe Dam to Lake Houston. Yet people still swim and fish in these waters. And more sand mines are expanding than closing.

2020 Texas Integrated Report Index of Water Quality Impairments. Coincidentally, this reach of the river is where most local sand mines are located.

I wish the TCEQ would step up inspections (especially after heavy rains) and increase fines for un-permitted discharges. Lake Houston, after all, is the source of water for more than 2 million people.

Section 3.2.2 – Ground Water Conditions

This section requires operators to study the impact on adjacent water wells, but specifies nothing to reduce the impact on them. Ooops. I suggest adding: “If present, waste management units must be located a minimum horizontal distance from adjacent water wells, in accordance with 16 Texas Administrative Code Chapter 76.”

Section 3.3.2 – Land Clearing and Grubbing Activities

Diverting upslope water around a planned area for disturbance is good; however, care must be taken to prevent diverted water from increasing downslope flooding. 

When the TCEQ says operators should clear and grub an amount of acreage that they can finish “before the next anticipated storm event,” it gives them an opportunity to clear hundreds of acres at once. Who can anticipate the next large rainfall in Houston? No one. Ask the people of Elm Grove how devastating sheet flow from a large area can be when a large rain hits before additional protections (i.e., detention ponds and berms) are installed.

Section 3.3.3 – Stripping Activities

The stockpile protection measures listed are good. But I would add that stockpiles must be located outside of FEMA-defined floodways.

This mine’s stockpile is located at the confluence of two floodways: for Caney and White Oak Creeks. Note the erosion after Imelda. Photo taken October 6, 2019.

Buffer widths between mines and adjoining properties are good. But I would add that “Additional buffer width or structures may be required where pipeline or utility corridors are located.

Pipelines carrying highly volatile liquids dangerously exposed by erosion from sand-mining activities on both sides of a utility corridor. This was easily preventable.

To Submit Public Comments

Please submit your thoughts on pre-mining and other BMPs to the TCEQ. Email Macayla.Coleman@Tceq.Texas.gov with the subject line “BMPs Guidance Document” before August 19, 2021.

Posted by Bob Rehak on 8/14/2021

1446 Days since Hurricane Harvey

The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.

Sand-Mine Structural Control BMPs Could Make Difference in Next Flood

In an effort to reduce sediment escaping into the San Jacinto River from sand mines, the Texas Commission on Environmental Quality (TCEQ) has issued Draft Guidelines on Best Management Practices (BMPs). Yesterday, I discussed vegetative controls for erosion. Today, I will discuss structural control. The two types often work together or in sequence.

At the very end of this post, I make some recommendations to strengthen BMPs, and describe how to submit public comments.

Structural Controls

Structural controls do several things:

  • Divert runoff away from disturbed areas
  • Reduce runoff velocities
  • Filter sediment
  • Remove sediment by ponding.

They include the following.

Temporary Structures (Section 2.2.1)

Installed before and during construction. After removing temporary stormwater controls the areas disturbed by the temporary structures must be revegetated.

Permanent Structures (Section 2.2.2)

Permanent structures remaining after construction. Once construction of areas outside of the sand-mining pit has ceased, permanent structural control BMPs must be implemented and operational.

Diversion Ridges, Berms or Channels of Stabilized Soil (Section 2.2.3)

These divert runoff into “sediment basins.” If they remain in place more than 30 days, they must be covered with temporary or permanent vegetation. Maximum allowable drainage area is five acres.

Silt Fences (Section 2.2.4)

Silt fences capture sediment from sheet flow. Six to eight inches of the fence material must be buried in a trench about four inches deep and four inches wide. Silt fences that are not buried have no useful function. They must never be installed across streams. Fencing must be removed when sediment deposits reach one-half the fence height.

Straw Bales (Section 2.2.4 Continued)

Can also be used as sediment barriers in small areas. Maximum grade: 3:1. Water depth must not exceed one foot at any point. Bales with bindings must be entrenched a minimum of four inches and anchored with stakes. Straw bales that are not buried are improperly installed.

Sediment Basins (Section 2.2.5)

Allow retention of sediment “prior to discharge” or recycling. Side slopes must be 2:1 or less. Sediment must be removed when the volume has been reduced to 27 cubic yards per acre of drainage area. Dikes must be well compacted and vegetated. Installed prior to construction but not in flowing streams. Use diversions to direct drainage to basins.

Better structural controls might have prevented a sand mine upstream from discharging 56,000 million gallons of white sludge into the West Fork in 2019.
Riprap Outlet Protection (Section 2.2.6)

Riprap outlet protection must be placed at the outlet end of culverts or channels to reduce the depth, velocity, and energy of water so that the flow will not erode the receiving stream.

Check Dams (Section 2.2.7)

Small dams across swales or drainage ditches that reduce flow velocity and erosion. Not used in flowing streams. Maximum height: two feet. Center must be at least six inches lower than the outer edges to prevent erosion around the edges. The maximum spacing between dams must be such that the toe of the upstream dam is at the same elevation as the top of the downstream dam.

Accumulated sediment must be removed from behind the check dams when it reaches one half the dam height. Erosion around dam edges must be corrected immediately, ensuring that the dam center is six inches lower than the edges.

 Construction Entrance/Exits (Section 2.2.8)

Aggregate must stabilize entrances and exits to reduce sediment tracked onto public roads. Aggregate must be at least six inches thick and 50 feet long. Tire washing may also be needed.

Housekeeping Practices (Section 2.2.9)

Petroleum products, paints, solvents, litter, debris, sanitary waste, and sediment from unstabilized areas, TCEQ BMPs specify:

  • Designated areas for equipment maintenance and repair;
  • Waste receptacles at convenient locations;
  • Regular collection of waste;
  • Protected storage areas for chemicals, paints, solvents, fertilizers, and other potentially toxic or hazardous materials; and
  • Adequately maintained sanitary facilities.
Post-Construction/Stormwater-Management Measures (Section 2.2.10)

Control measures must be installed to control pollutants in stormwater after construction is complete. These controls include, but are not limited to:

  • Retention ponds. Minimum volume is the first inch or half inch of stormwater runoff containing the first flush of pollutants.
  • Vegetated Swales and Natural Depressions. There are grass-lined areas that filter sediments from runoff, thus helping to prevent erosion. Vegetated swales must have side slopes of 4:1 or less.

General

As with vegetative controls, operators must inspect structural controls once every seven (7) calendar days. That includes controls in areas used for storage of materials; maintenance areas; plus site entrances and exits.

Operators must replace or modify ineffective or damaged structural controls “in a timely manner, but no later than the next anticipated storm event.”

Recommendations for Public Comment Structural Controls

As we saw in yesterday’s post on vegetative controls, I have often seen gaps between real and ideal. However, for this post, I realized in looking back through thousands of aerial photos today, that I have never photographed one:

  • Stabilized channel
  • Silt fence
  • Straw bale
  • Check dam
  • Outlet stabilized by riprap or
  • Vegetated swale

…on a sand mine site. Period. Let alone one that met these requirements.

I’m not saying they don’t exist. I’m just saying that I’ve never seen them on the days I flew over.

Maybe operators feel they don’t need them. Or maybe they’re just not using them for other reasons.

So once again, I recommend that you write the TCEQ and ask them to put teeth into their BMP requirements.

In addition, I recommend you request:

  • Stronger wording on the general requirement to fix damaged or ineffective structural controls in a “timely manner.” That’s just too subjective. It lets operators defer maintenance way past the point it may be needed.
  • Clarification on “prior to discharging” in section 2.2.5. Are operators capturing sediment only to discharge it into the river at a later time? What do they mean by discharge? Where?
  • Detention ponds big enough to catch an inch of rain in an area where Atlas 14 requirements specify 16.9 inches of rain in 24 hours? (Section 2.2.10) That seems wholly inadequate. Harris County Flood Control District recommends minimum detention volumes for developments at .65 acre feet per acre for areas up to 640 acres. That’s about 8 inches of rainfall.

Please submit your thoughts on structural control and other BMPs to the TCEQ by emailing Macayla.Coleman@Tceq.Texas.gov with the subject line “BMPs Guidance Document” before August 19, 2021.

The house you save could be your own.

Posted by Bob Rehak on 8/13/2021

1445 Days since Hurricane Harvey

The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.

How Vegetative Controls Can Help Sand Mines Reduce Erosion and Flooding

During Harvey, millions of cubic yards of sediment moved downstream. Some came from river bank erosion. But some also came from exposed sediment in sand mines that flank both sides of the West Fork like the one below.

West Fork Sand Mine photographed May 5, 2021. Such mines occupy 20 square miles in a 20 mile stretch between I-45 and I-69.

It’s exceedingly difficult to determine the percentages that came from various sources. Regardless, sediment built up at key places, blocking both the West Fork and its tributaries. Those blockages backed water up into thousands of homes and businesses.

The mouth bar of the West Fork (photographed after Harvey) is now gone thanks to three years and more than $100 million of dredging. Ten feet of sediment was deposited in this area during Harvey, severely restricting the conveyance of the river and contributing to the flooding of thousands of homes and businesses.

Ever since then, the Lake Houston Area Flood Prevention Initiative has lobbied the Texas Commission on Environmental Quality and the Texas Aggregate and Concrete Association to adopt a comprehensive and improved set of best management practices (BMPs).

In yesterday’s post, I discussed setbacks from rivers, a major improvement in the new BMPs now being considered. Today, I will discuss vegetative controls in the Draft of Proposed BMPs, now in the public comment period. If observed, they could reduce sedimentation and flooding. If not, we could have more problems right here in River City. So please get involved.

Section 2.1 Vegetative Controls

Vegetative controls play a major role in minimizing soil exposure, erosion and runoff.

A large part of the new BMPs, Section 2.1, deals with vegetative controls. I summarize and liberally quote from that section below so that boaters, neighbors and community officials will know what the TCEQ expects mines to do. Also, the wording in one section should be strengthened to eliminate ambiguity. I will call it out below for readers so you can request the TCEQ to improve the language.

How Vegetation Helps Reduce Erosion

According to the TCEQ, “Vegetation is an inexpensive and effective way to protect soil from erosion. It also decreases erosion from flowing water by reducing its velocity. Roots hold soil and increase infiltration. In areas that are outside the active sand mining operation and not expected to handle vehicle traffic, vegetative stabilization of disturbed soil is required using the BMPs described below.”

Only Plants Appropriate for Region

“Vegetative controls must consist of plants appropriate for the ecoregion where the site is located and must not include any noxious or invasive species.” They then provide links to several acceptable lists.

Weekly Inspection Required

“Site operators must inspect and document disturbed areas of the site where vegetative controls have been implemented once every seven (7) calendar days. Operators must inspect all vegetative controls to ensure that they are installed properly, appear to be operational, and minimizing pollutants in discharges, as intended.”

A sentence farther down can be improved. “Operators must replace or modify controls [that have failed] in a timely manner, but no later than the next anticipated storm event.”

Opportunity for Improvement:

TCEQ never defines the “next anticipated storm event.” For the last month, widely scattered thunderstorms have caused street flooding in parts of Houston will leaving others untouched. No one can predict with certainty whether one of those storms will park over a sand mine. This gives the sand miners an opportunity to delay repairs almost indefinitely.

See suggested change at end of post.

2.1.1  Vegetative Buffer Zones

“Vegetative buffer zones are continuous undisturbed or planted vegetated areas that surround a development, land disturbance activity or that border an intermittent stream or permanent water body. Buffer zones aid in sediment filtration and removal by blowing surface water flow through these areas. Construction site runoff must be dispersed over the entire buffer zone if possible. A minimum 100-foot buffer zone is required adjacent to perennial streams greater than 20 feet in width, 50 feet for perennial streams less than 20 feet in width, and 35 feet for intermittent streams.”

Lack of a vegetated buffer zone allows sand from this stockpile to erode into White Oak Creek. Notice large swirls of sand cascading down the slopes into the creek.

2.1.2  Sod Stabilization

Sod stabilization involves establishing long-term stands of grass with sod on exposed surfaces. When installed and maintained properly, sodding can be more than 99 percent effective in reducing erosion.

During May 2021 floods, the East Fork San Jacinto swept through the abandoned Texas Concrete Sand & Gravel Plum Grove Mine. The area circled in red was exposed to floodwaters. See below.
Close up of area above taken two months earlier, but still after site was abandoned. No sod.

Protection of Trees

“Protection of trees involves preserving and protecting selected trees that exist on the site prior to development. Mature trees provide extensive canopy and root systems that hold soil in place. Shade trees also keep soils from drying rapidly and becomingsusceptible to erosion, as well as increasing property value. Consideration must be given to the tree root structure.”

“If trees die or are no longer viable for soil stabilization for any reason, then they must be replaced within 30 days with any equivalent or better soil-stabilizing tree.” 

2.1.3  Temporary Seeding

“Temporary seeding is the planting of fast-growing annual grasses to hold the soil in areas that will not be disturbed again for 30 or more days. For long-term protection (greater than one year), permanent seeding must be initiated. Mulching helps ensure seed growth and maintains soil moisture and helps prevent erosion. It is essential when slopes are steep, the weather is hot or dry, and soil conditions are not favorable.”

Ooops. Note steep, unvegetated banks on this West Fork dike in foreground which breached multiple times.

“Tillage, with lime and fertilizer, to maintain adequate soil pH and nutrient content, may be important before seeding.”

2.1.4  Permanent Seeding

“Permanent seeding is the use of perennial grass (with trees and shrubs) to stabilize the soil. Vegetation is often not fully established until one year from planting. Inspect, repair and re-seed as needed, evaluating choice of seed and quantities of lime and fertilizer. Use temporary seeding if the time of year is not appropriate for permanent seeding.”

2.1.6  Mulching

“Mulching is the placement of hay, grass, wood chips, straw, or synthetic material on the soil. Mulch holds moisture, lessens temperature extremes, and retards erosion on steep slopes during seed establishment. Soils that cannot be seeded due to the season must be mulched to provide temporary protection. Operators must apply the mulch in an appropriate manner that prevents the mulch from leaving the site during heavy rain events.”

2.1.7  Erosion and Sediment Control Blankets

“Erosion and Sediment Control Blankets are machine-produced mats of straw or other fibers held together with netting that provide temporary or permanent stabilization in critical areas, such as slopes or channels, so that vegetation may be established. These blankets often contain seeds to help establish vegetation.”

The Artavia Development in Montgomery County appears to be routing its main drainage ditch through this old sand mine. This area perpetually eroded. This swale covered by what appears to be an erosion blanket may help reduce that in the future. Note erosion already existing to left of blanket.

2.1.8  Surface Roughening

“Surface roughening, using heavy equipment, creates horizontal grooves across the slope which reduces runoff velocity/erosion and aid the growth of seed. Roughened slopes must be immediately seeded and mulched.”

To make this work, the slopes would need to be gentle enough to catch rainwater on its way to the pond or river. Unfortunately, you don’t often see gentle slopes in San Jacinto mines, if at all.

Summary and Call to Action

Virtually all of these BMPs call for regular inspections and maintenance. The most troubling part of them is the sentence highlighted above about the next “anticipated storm.” A sand miner could build a case for ignoring virtually all of these by claiming he didn’t anticipate storms anytime soon. But by the time a storm like Harvey or Imelda approaches, or even one of the May storms that dumped 7 inches of rain on Kingwood in three hours, it would be too late to replant vegetation. It needs time to regrow.

I suggest replacing “next anticipated storm” with “must repair or replace controls immediately when damage is noted during weekly inspections.”

Please submit your thoughts on this and other BMPs to the TCEQ by emailing Macayla.Coleman@Tceq.Texas.gov with the subject line “BMPs Guidance Document” before August 19, 2021.

Posted by Bob Rehak on 8/12/2021

1444 Days since Hurricane Harvey

The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.

We Must Strengthen Sand-Mining BMPs: Minimum Setbacks Just Part of Solution

At long last, the State of Texas could soon adopt minimum setbacks from rivers for sand mining.

The Lake Houston Area Flood Prevention Initiative has been working with the Texas Aggregate and Concrete Association (TACA) and the Texas Commission on Environmental Quality (TCEQ) for two years to create a set of Best Management Practices (BMPs). The BMPs would apply only to sand-mining operations in the San Jacinto River Watershed.

The TCEQ has published a draft of proposed regulations and is now seeking public comment. Comments are due by August 19.

The proposed regulations are a great step forward in one sense. They plug some gaping holes that Texas has compared to other states. However, I believe they can and should be stronger.

Texas Currently Has No Minimum Setbacks

For instance, take minimum setbacks from rivers. Right now, Texas has no minimum setback. Some mines can and do mine right up to the edge of rivers, leaving only the width of a flimsy dike made out of sand between them and a raging river when floodwaters rise.

  • Most states define 100 feet as the minimum setback.
  • Alaska sets the minimum from a public water supply at 1,000 feet.
  • But other states, such as Arizona, take another approach altogether. Instead of specifying fixed widths, they define “erosion hazard zones.”

Erosion Hazard Zones Substituted for Defined Distances in Some States

Erosion hazard zones would take into account factors such as whether mining occurred on the eroding side of a river or on the side where sand is building up. An erosion hazard zone might also take into account the steepness of the surrounding slopes. Such zones are based on site assessments by engineers and may even take into account rates of river migration.

An erosion hazard zone might also take into account being downstream from the Lake Conroe Dam which released 80,000 CFS on top of Harvey’s already prodigious floodwaters. By itself, 80,000 CFS would have been the ninth largest flood in West Fork history.

The draft regulations currently under consideration specify a minimum 100-foot buffer zone adjacent to perennial streams wider than 20 feet, 50 feet for perennial streams less than 20 feet wide, and 35 feet for intermittent streams.

To learn more about how other states and countries handle setbacks, see the links on the Sand Mining page.

Minimum Setbacks By Themselves Are Only Part of Solution

Since Harvey, I have flown up and down the East and West Forks of the San Jacinto dozens of times and taken more than 27,000 photographs.

I have witnessed many dike breaches. Sometimes they are intentional.

Sometimes a large storm causes rivers to erode into pits – a phenomenon called pit capture.

Here, one mine leaks into a second mine (abandoned in lower right), which in turn leaks into West Fork 1200 feet away.
Breach in 400-foot wide buffer zone that happened sometime after Harvey. Exact date unknown.
This mine along Caney Creek had a 150-foot-wide vegetated buffer, that held just fine through Harvey, but miraculously couldn’t survive the unnamed flood of May 2019.
Stream level photo of breach above. Note the trackhoe marks on the side of the breach.

The point is this. Even with 100 foot setbacks, many breaches still occur. If a mine wants to get rid of wastewater, it will find a way.

It can always just pump water over the side of a dike.

One of many pumping operations I have documented.

Some put pipes through dikes to ensure wastewater never exceeds a certain level.

One of many pipes I have documented.

Or they can build dikes out of materials designed to fail under pressure.

Former dike at Triple PG mine being sued by Texas Attorney General

The hundred foot setbacks would, however, make many of these practices more difficult by making them more conspicuous.

And the requirement to have the buffer zone vegetated (another BMP), would eliminate situations like the narrow strip below.

Easily erodible, unvegetated buffer strip with steep sides at mine on West Fork (foreground).

My Take

All things considered, when the penalty for non-compliance averages $800 per incident, some will continue to ignore BMPs. Not all. But some.

As of August 2018, TCEQ had raised a half-million dollars in fines for more than 13,000 incidents statewide during the previous five years. If you look just at the last half of 2017 (after Harvey), the TCEQ levied about $140,000 in fines STATEWIDE – far less than it cost to repair ONE average home in Kingwood as a result of Harvey.

That’s why I say that by itself, the width of a buffer strip will help, but not solve the problem.

How do you feel? $220 million of your tax dollars are going toward dredging. Please share your feelings with the TCEQ.

How to Make a Public Comment

Submit written comments on BMPs to Macayla.Coleman@Tceq.Texas.gov with the subject line “BMPs Guidance Document” before August 19, 2021.

Posted by Bob Rehak on 8/11/2021

1443 Days since Hurricane Harvey

The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.

Harris County Commissioners Approve Atascocita Drainage Study

Harris County Commissioners today approved a drainage study for Atascocita. The agenda item read, “Recommendation to initiate and proceed with planning, right-of-way acquisition, design and construction of general drainage improvements in the Atascocita area. (San Jacinto River Watershed, Bond ID F-15, HCFCD Unit G103-00-00, Precincts 2 and 4). The bond allocates $10 million for all of that.

Project Area and Scope

Atascocita project area. Roughly half is in Precinct 2 and half in Precinct 4.

Sources at HCFCD say that the project will follow the model of the Kingwood Drainage Assessment. It will identify where the worst flooding occurs and where to attack first.

People in Atascocita have waited a long time for this project to kick off. We’re now about two weeks from the fourth anniversary of Hurricane Harvey.

When complete, this project will identify streams, channel types, ownership, current level of service, improvements, rights of way needed, cost estimates and detention estimates for all the projects considered in the Atascocita area.

One of Last Projects in Flood Bond to Start

The project had been deferred until now because it fell into the fourth quartile of the equity prioritization framework. Accordingly, the Atascocita study will be one of the last projects to be initiated in the bond program. Sources at HCFCD say that soon, all projects will have started – a major milestone.

Posted by Bob Rehak on 8/10/2021

1442 Days since Hurricane Harvey

FEMA Awards Nearly $250 Million to HCFCD for Sediment Removal

This morning, Harris County Flood Control District (HCFCD) announced an award of nearly $250 million from the Federal Emergency Management Agency (FEMA) to remove accumulated sediment from eight watersheds. They include:

  • Willow Creek
  • White Oak Bayou
  • Spring Creek
  • Little Cypress Creek
  • Greens Bayou
  • Cypress Creek
  • Barker Reservoir
  • Addicks Reservoir
Cypress Creek erosion near TC Jester. Photographed on 7/24/2021.

Removing More than 2 Million Cubic Yards Deposited by Harvey

Extreme flooding from Hurricane Harvey deposited the sediment when banks eroded and in some cases collapsed.

“This award allows us to continue the huge task of removing sediment from Flood Control District channels. It is estimated that more than 2.13 million cubic yards of sediment accumulated in multiple watersheds during the storm – enough to fill 213,000 dump trucks,” said Alan Black, Harris County Flood Control District Interim Executive Director. 

$6.25 Million Leverages Almost a Quarter Billion

“It will take several years to complete construction, but this award will allow us to make repairs to the drainage system and to restore the facility back to pre-disaster design, capacity and function. The federal cost share for this project is 90 percent, which allows our local taxpayer dollars to go further. We are extremely thankful to FEMA and TDEM (Texas Division of Emergency Management),” he continued.

The Flood Control District will be responsible for the remaining 10 percent of the project cost.  However, thanks to legislation passed by the Texas State Legislature in 2019, which established the Texas Infrastructure Resiliency Fund – Hurricane Harvey Account, the State of Texas is expected to reimburse up to 75 percent of that local share, bringing the total cost to the Flood Control District down to approximately $6.25 million.  

Construction to Start in Late 2022

According to Black, the cutting edge methods used by the Flood Control District team have rarely, if ever, been used on such a scale and took several years of close collaboration with TDEM and FEMA to receive approval.

As we have seen with other projects since Harvey, this is a complex process involving multiple steps. The money first has to work its way down from Washington. Then HCFCD must get it from TDEM. After that come preliminary engineering, final engineering, permitting, bidding, and approvals.

HCFCD expects first construction to start sometime in late 2022.

Posted by Bob Rehak on 8/9/2021

1441 Days since Hurricane Harvey

Tropical Wave 94L Approaching Barbados This Morning

The National Hurricane Center (NHC) is currently tracking two tropical disturbances in the Atlantic Basin. The one closest to the Caribbean rates a 70% chance of development. The system is not currently a threat to the Gulf of Mexico but you should keep your eye on it.

Invest 94L is the red.

Invest 94L

According to the NHC, showers and thunderstorms have become more concentrated this morning in association with a low pressure system located about 150 miles east of Barbados.

Environmental conditions favor additional development. A tropical depression will likely form later today or tonight while the low moves west-northwestward at 10 to 15 mph.

The disturbance will reach portions of the Lesser Antilles tonight. It will move near the Virgin Islands and Puerto Rico on Tuesday and reach Hispaniola around the middle of this week. Tropical storm watches or warnings could be required today with shorter-than-normal lead times for portions of the Lesser Antilles, the Virgin Islands, and Puerto Rico.

In addition, heavy rains and flooding are likely for the Leeward Islands, Virgin Islands, and Puerto Rico.

Radar from Barbados along with satellite images show a broad and elongated area of low pressure with scattered to numerous areas of disorganized convection. Details on the exact track will be important as to determine how much the system will interact with the island chain.

Jeff Lindner, Harris County’s meteorologist warns that, “While the system is currently no immediate threat to Texas, residents should at least keep an eye on the forecast for updates over the next week.”

Second Area Less of a Threat

Disorganized showers and thunderstorms have changed little in association with an elongated low pressure area located several hundred miles east of the Lesser Antilles. Development of this system is becoming less likely during the next few days while it moves toward the west or west-southwest at around 10 mph. Formation chance through 5 days…low…20 percent.

Preparedness

The peak of hurricane season is just a little more than a month away. This is the time of year when you should become serious about preparedness if you haven’t already done so.

Posted by Bob Rehak on 8/9/2021 based on information from the NHC and HCFCD

1441 Days since Hurricane Harvey

Comments Due to TCEQ on Sand-Mining BMPs by August 19

A couple weeks ago, I posted about rules governing the application of sand mining best management practices (BMPs). Now the Texas Commission on Environmental Quality (TCEQ) is accepting public comments on the BMPs themselves. Think of the difference this way: how/when to enforce guidelines vs the guidelines themselves.

More than 90 people responded to the enforcement question. Thank you. The TCEQ left so many “outs,” it was doubtful whether sand mines would ever have had to follow any of the BMPs.

Comments Coming Due on BMPs, Not Just Rules Governing Them

Now it’s time to consider the content of the BMPs themselves and provide public comment.

We have more time this time – until August 19. So I will publish a series of posts about different aspects of the BMPs that I believe could be improved.

Here is a draft of the 24-page document listing all BMPs that the TCEQ is considering.

Today, I will simply give you an overview of the major categories of recommendations. In coming days, I will discuss major areas of concern. These will be things where, in my opinion, the sand mines in the San Jacinto watershed fall short of ideal practices in ways that directly contribute to flooding.

Some Caveats

Having said that, let me also qualify that last statement three ways:

  1. Not all sand mines are bad actors, but some are.
  2. We need sand to make concrete.
  3. Sediment comes from both man-made and natural sources. While massive amounts of sand clogged our river after Harvey, it’s unclear what proportion of that came from sand mines.

It’s easy to see that floodwaters eroded stockpiles, breached levees, and swept sediment downstream. It’s also easy to see how suboptimal sand mining practices contributed to those issues.

Sand mining increased the width of the exposed sediment adjacent to the river by an average of 33X.

USGS calculations, photographs, and first responder reports during Harvey also indicate that the velocity of the river was sufficient to transport not just sand, but large chunks of gravel.

However, it’s not clear how much suboptimal sand mining practices contributed to blockages, such as the East and West Fork Mouth Bars, Sand Island, and the giant side bar that blocked the Kingwood Diversion Ditch. Some likely also came from erosion of the river bed itself as well as upstream developers with suboptimal practices of their own.

It will take someone smarter than me to figure that how much came from where.

The Public Policy Question

It is clear, however, that we’re investing $222 million in dredging to eliminate sediment blockages that contribute to flooding. And many sand mines have shown, in my opinion, a callous disregard for the cleanup costs they externalize to the public sector. One is even currently being sued by the Texas Attorney General.

Scope of BMPs Being Proposed

The BMPs being considered by the TCEQ have to do with:

  • Vegetative and Structural Controls to help reduce erosion
  • Pre-Mining site evaluation, drainage studies and site preparation
  • Mining activities, such as dredging, processing, maintenance, and the handling of petroleum products
  • Post-Mining site stabilization, debris removal, and property grading
  • Requirements for a final stabilization report.

I will discuss each of these in coming days before the deadline. I will also show photos that illustrate how current practices fall short of BMPs and contribute to sedimentation.

Sand mine pumping wastewater directly into San Jacinto West Fork
Another sand mine discharging wastewater directly into the West Fork.

Two things ARE clear, however. We can and must do better if we want to reduce:

  • Financial hemorrhaging
  • Flooding from man-made blockages that clog our rivers.

How to Make a Public Comment

Submit written comments on BMPs to Macayla.Coleman@Tceq.Texas.gov with the subject line “BMPs Guidance Document” before August 19, 2021.

More details to follow in the coming days.

Posted By Bob Rehak on 7/8/2021

1440 Days since Hurricane Harvey

The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.

Improved TexasFlood.org Website Shows Spread of Floodwaters and Inundated Buildings by Gage Height

The Texas Water Development Board (TWDB) has reorganized the sea of flood-related information and redesigned the TexasFlood.org website to provide a more user-friendly resource for Texans who want to increase their flood awareness and preparedness.

Given the deadly nature of flood events and the rapid timeframe in which they can occur, remaining flood-ready is essential.

One Feature Shows Flood Spread and Inundated Buildings by Gage Height

TexasFlood.org provides fundamental information on emergency preparation for and recovery from flood events, as well as web tools to better understand flood risk, in a format that is easy to access and easy to understand.

One of the most useful new features is an interactive map that shows the spread of floodwaters based on the gage height.

Select a gage and a height and see instantly how far the floodwaters will spread. This shows spread based on the USGS Gage at FM1485 and the East fork.

I selected the height of the highest gage reading during the May floods this year at FM1485 and the East Fork. Then I zoomed in and found that 36 structures were in danger of being inundated. You can even see their locations!

Information like this is not only useful when considering purchasing a building, but also when considering whether to evacuate.

Other Useful Features

TexasFlood.org also features resources and tools that allow users to:

  • Review lake levels and river heights
  • Check current precipitation totals and weather conditions
  • Evaluate potential flood risk
  • See the impacts of different hypothetical flooding scenarios
  • Identify and connect with their local floodplain administrator
  • Learn the primary types of flooding and basics of flood insurance

The website highlights the reasons why emergency preparedness is vital to proper flood preparedness, including the importance of floodproofing and awareness of second-order damages after a flood event.

One-Stop Information Shop

The TWDB has gathered important information from other local, state, and federal entities to provide the most relevant information for Texans in one convenient online location. Hurricane season runs through November 30 each year. And historically speaking, 80% of the storms for this year are still in front of us. Just today, the National Hurricane Center highlighted another area of concern in the Atlantic, bringing the active total to three.

So TWDB encourages all Texans to check out the revamped TexasFlood.org. Learn how to pack a flood kit, download resources to prepare family, review individual flood risk, plan an evacuation route, and more.

Posted by Bob Rehak on 8/7/2021 based on a press release by TWDB

1439 Days since Hurricane Harvey