Five pipelines carrying highly volatile liquids (HVL) through the utility corridor that crosses the LMI River Road sand mine in Conroe have been buried again. Repairs have almost finished. Last Friday, crews were removing construction equipment and cleaning up. This significantly reduces risk to the public from a pipeline leak, rupture or explosion.
Erosion Triggered by Mining Too Close to Utility Corridor
In the last month, workers made progress on pipeline bed repairs to two area sand mines. But repairs at one sand mine look substantial. At another, they look superficial. Triple PG in Porter is still edging into the danger zone.
Exposed by Erosion When Mining Came Too Close
In December and January, I posted about pipelines exposed when sand miners mined too close to them. Floodwaters then swept through the mines and undercut the pipelines, creating safety hazards.
Several HVL (highly volatile liquid) pipelines (above) and one natural gas pipeline (below) were affected at mines in Conroe and Porter.
Here’s where things stand on repairs at both mines as of last week..
Triple PG Mine in Porter: Another Big Cover Up
The Triple PG Mine in Porter has covered up the exposed natural gas pipeline with sand. As of 2/13/2020, Triple PG had made no other visible attempts to stabilize the area, which is subject to repeated erosion. Harvey first exposed the pipeline, which Triple PG subsequently covered. Then Imelda re-exposed it. And Triple PG re-covered it.
Readers may remember that after Harvey, Kinder Morgan tunneled 75 feet under the mine and spliced in a replacement for the section that had been exposed. They then filled the cutoff section with inert gas. So the exposed section was not active.
Still, without further stabilization, the pipeline will likely be exposed again and again by future storms.
Triple PG still has made no attempt to stabilize erosion creeping toward the HVL pipelines that cross the mine in a utility corridor. The same erosion that exposed the natural gas pipeline will threaten those in future storms.
Liberty Materials Mine in Conroe: Fix Nearing Completion
At a Liberty Materials Mine in Conroe, a much more substantial fix is underway by the pipelines. The mine spanned both sides of the utility corridor. Water from one side, trying to get to the river on the other, washed under several HVL pipelines, exposing them.
Repairs began in January and were well under way in February. Crews first expanded the washed out area under the pipelines. Then they placed two giant culverts under the pipelines to allow water to move from one side to the other. They also cemented the culverts in place and drove vertical steel reinforcements in the ground to prevent re-exposure of the pipelines.
As of 2/13/2020, crews were filling dirt in under, around and over the pipelines.
The repairs here appear much more substantial than in the Triple PG mine. I just hope the volume of sand washing from one section of the mine to the other does not clog the culverts. The steel reinforcements will protect the pipelines in this location, but water has a habit of flowing around obstacles.
Posted by Bob Rehak on 2/23/2020
908 Days after Hurricane Harvey 157 since Imelda
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/02/20200213-RJR_7697.jpg?fit=1200%2C800&ssl=18001200adminadmin2020-02-23 10:43:352020-02-23 10:57:20Progress on Pipeline Repairs at Sand Mines