ENFORCE23038

• Permit No: C1982056
• IBM Index Class Name: Enforcement
• Doc Date: 6/6/2005
• Doc Name: Operator Comment Letter
• From: Twentymile Coal Company
• To: DMG
• Violation No.: CV2005006
• Media Type: D
• Archive: No

"1
Jerry Nettleton To [e-mail]
05/05/2005 08:42 AM Delbert Lobb/TWMlPeabody@PeabodyEnergy,
cc [e-mail],
[e-mail], Dave
bcc
Subject Twentymile Coal - OSMRE Oversight Inspection Issues
Byron -
I was disappointed, as I'm sure you were, that we had the two issues identified in the field during our
inspection. As you know, we have been working diligently to make sure that things are in good order and
full compliance. In order to both understand why the observed problems occurred and to address them
appropriately in a timely manner, I am proceeding with an internal inquiry, and have obtained the following
additional relevant information:
Discharge at Northwest Mains Ventilation Fan Installation
On Monday night during graveyard shift (prior to our inspection on Tuesday morning), we had a roll seal
fail on our underground mine water system. Our mine water system supplies cooling and dust control
water to both the longwall and the continuous miners used for development work Because of the volume
of water required, the system operates at high pressures (300 - 700 psi, compare with a typical pressure
washer at 250 - 500 psi). When the roll-seal (which is a pressure accumulator device) failed, pressure in
the system built-up and started causing pipe joints to fail and separate. When this was discovered, valves
were shut-off to minimize damage to the water system and prevent uncontrolled flow underground
The pipe that we observed at the Northwest Mains Vent Fan is connected to the mine water system and is
designed to function as a pressure relief and accumulator. As I understand it, the approximately 1,000'
column of air in the pipe serves as a buffer to minimize air-hammer in the system with pressure changes
and has functioned effectively for some time. With failure of the roll-seal and closure of valves
underground, pressure in the water system built-up to well above normal levels and was sufficiently high
to allow water to push the column of air out the relief pipe, resulting in surface discharge. Until it was
discovered early Tuesday morning that there was discharge from the pipe, flows as high as 200 gpm may
have occurred. When we visited the site, I was unaware of the underground water problems and related
surface discharge, but as I indicated to you and Mitch, was suspicious that the localized surface flooding
that we were seeing was due to something other than normal runoff It was during the subsequent part of
the inspection that I was able to talk with Mike Berdine (on the road to the 18-Right Shaft) and find out
what had happened.
The discharge that resulted in the observed problem was due to unanticipated operational(upset)
conditions, and discharge volumes far exceeded the design storm runoff for this area and for the designed
drainage and sediment control structures, Fortunately, discharge was contained within the immediate and
adjacent areas by the designed system and natural topographic features, resulting in little or no discharge
to Fish Creek. Discharge flows were also clean mine water that is not sediment laden like typical
disturbed area runoff. Under normal surface runoff conditions, the designed system has function
effectively to control surface runoff and sediment
On Tuesday, a valve was installed on the accumulator pipe to prevent further or future discharge I am
meeting with our Mine Manager, Chief Engineer, Surface Foreman, Electrical Foreman, and Underground
Maintenance Foreman this morning to go look at the problem area, discuss what occurred and why, and
define specific steps and schedule to both address the immediate problem and assure that it does not
occur again at this or any other location.
18-Right Intake Shaft Access Road
I talked with both our Surface Foreman and the Contractor, who has done most of the work on the