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Thank you for the information, Mason.
Please proceed with implementing both of your proposed changes if possible.
Kind regards,
![[20260407_19d68e55e45d_image001.jpg]]
Mychal Jones
Plant Superintendent/Chief Plant Operator
Phone 805-489-6666 ext. 103
Web https://sslocsd.org/ Email mychal@sslocsd.us
1600 Aloha Place, Oceano, CA. 93445
From: Mason Radke <mason@autosysnet.com>
Sent: Tuesday, April 7, 2026 9:43 AM
To: Mason Radke <mason.radke@gmail.com>; Mike Arias <arias@sslocsd.us>
Cc: Mychal Jones <mychal@sslocsd.us>; Kevin Seifert <kevin@autosysnet.com>
Subject: Re: SCADA investigation
WAS Pumping System — Unplanned Shutdown Summary
April 5, 2026
I looked into the unexpected WAS pumping shutdown that occurred at 11:58 AM on April 5. All trend values dropped at the exact same moment with no fault, interlock, or other automated condition that would explain it. The only alarm that fired was a low flow deviation on FIC4610, which was simply a result of the pumps stopping and not the cause. Based on everything we saw, the most likely explanation is that the SCADA Stop button was hit accidentally.
To prevent this from happening again, two small changes are proposed:
1. Log the Stop command — Every time the WAS Stop button is pressed, a timestamped entry will be recorded in the data log. This gives a clear record to reference if something like this comes up again.
2. Add a confirmation step — A popup confirmation will be added to the Stop button so operators have a chance to cancel before the shutdown executes. This makes an accidental press a non-issue.
Neither change requires any modifications to the PLC or field equipment. Please let me know if you would like me to spend time on this. I estimate 1-2 hours to get those changes implemented and tested.
Mason Radke
Autosys, LLC
From: Mason Radke <mason.radke@gmail.com<mailto:mason.radke@gmail.com>>
Date: Monday, April 6, 2026 at 2:05 PM
To: Mike Arias <arias@sslocsd.us<mailto:arias@sslocsd.us>>
Cc: Kevin Seifert <kseifert@nviro.com<mailto:kseifert@nviro.com>>, Mason Radke <mason@autosysnet.com<mailto:mason@autosysnet.com>>, Mychal Jones <mychal@sslocsd.us<mailto:mychal@sslocsd.us>>
Subject: Re: SCADA investigation
i can take a look this afternoon. i'll let you know if theres enough information logged to tell you for sure. would you like a confirmation pop up on that button? to help prevent it from being accidentally hit again?
On Mon, Apr 6, 2026 at 1:59 PM Mike Arias <arias@sslocsd.us<mailto:arias@sslocsd.us>> wrote:
Good Afternoon Gentlemen,
Yesterday, 4/5/26 at approximately 11:58am our WAS pump shut down. We think we know what happened but are wondering if either one of you could confirm this for us? We believe that an Operator may have hit the stop button for the WAS pump. From the Aeration screen/button to the Secondary Clarifier and WAS button, then to setpoints. We believe that when the Operator was entering the wasting gallons for the day that the WAS pump Stop button was inadvertently pressed. Any was that you could confirm this for us? Thank you.
Best regards,
Michael Arias
Michael J. Arias
Operations Supervisor
Grade III Operator
South San Luis Obispo County Sanitation District
1600 Aloha Place, Oceano, Ca.
805-489-6666
[South San Luis Obispo County Sanitation District]
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-Mason