Letter regarding STEP tank
City of Yelm
Community Development Department
105 Yelm Avenue West
P.O. Box 479
Yelm, WA 98597
October 11, 2007
Sherlita Kennedy, Manager
Yelm Wal-Mart
17100 SR 507 SE
Yelm, WA 98597
Sherlita:
As you may be aware, the City of Yelm has been closely monitoring the STEP tank at Wal-Mart since early September at which time our Public Works staff had noted that the system was not
working as designed.
Specifically, on September 6, the City pumped the STEP tank as the screens were partially blocked by paper products and rubber gloves and flows from the side sewers were much greater
than anticipated by water usage calculations developed by Wal-Marts engineer during the preparation of civil engineering plans.
After pumping the tank, the City monitored sewage flows and it appeared that the flows on September 6 were extraordinary and may have been caused by a blockage in the side sewer from
the inappropriate materials found in the tank (paper products and rubber gloves). At that time, the City believed that the problems were most likely caused during the initial stocking
of the store from employees flushing the materials that caused the blockage at the STEP tank screens.
However, the Public Works Department inspected the STEP tank again on October 9th and found the condition to be similar to that found in September, with the screen plugged and the pumps
constantly cycling. The City will again have to pump this tank at a cost of approximately $1,600, not including staff time.
This condition is not acceptable and needs to be addressed immediately. Specifically, the following remedial steps will be required:
All invoices for pumping the STEP tank will be forwarded to Wal-Mart for payment until the problem is solved.
Each toilet in every restroom, both public and employee, must be signed with a placard that warns against the introduction of inappropriate material into the sewer system.
No later than October 31, 2007, Wal-Mart shall submit to the City Community Development Department a peer report from a licensed engineer with experience with STEP sewer systems (not
PACLAND, Inc.) analyzing the operation of the STEP tank and the size of the STEP tank related to peak flows into the tank. If the report concludes that the tank is not operating as
designed or undersized, it shall include a recommendation for repair or replacement of the tank. All recommendations of the report approved by the City shall be implemented no later
than November 15th.
Thank you for your immediate attention to this matter.
Sincerely,
Grant Beck, Director
Department of Community Development
c. Tim Peterson, Public Works Director
Jon Yanasak, Sewer Treatment Plant Manager
Jim Gibson, Development Review Engineer
Allen Seay, Wal-Mart Stores, Inc.
Mike Beach, PACLAND, Inc.