NC0059251_LM-2020-0074 Response_20210125

January 4, 2020
Lon T. Snider, Regional Supervisor
Water Quality Regional Operations Section
Winston-Salem Regional Office
Division of Water Resources,NCDEQ
Subject: Notice of Violation & Intent to assess Civil Penalty RECEIVED
Tracking Number: NOV-2020-LM-0074
Permit Number NC0059251 JAN 2 5 2021
Quail Acres Mobile Home Park
Rockingham County NCDEQ/DWR/NPDES
Mr. Snider,
Thank you for allowing Quail Acres Mobile Home Park the opportunity to respond to the Notice of
Violation dated November 4, 2020; received December 30, 2020. Below we address the following
infractions that occurred during the month of May, 2020.
During the May 2020 period, total ammonia nitrogen exceeded the allowable monthly average limit, as
well as total influent flow. Over 5 inches of rainfall accumulated over the course of the month. The
increase in flow impacted the performance of the treatment system. The increased hydraulic loading on
the filter media presented operational challenges not allowing for intermittent loading of the sand [e.g.
short circuiting] and the filter bed became hydraulically overloaded. The intermittent loading is
important for nitrification as it provides a mechanism for air to penetrate the sand granules allowing
nitrifier growth. The high flow increased the number of loading events, thus, reducing the time between
loading creating an environment of reduced oxygen that impacted the performance of the filter media.
Optimal conditions occur when the media is loaded in or around 48 times per day.
The daily ammonia nitrogen results of 5.8 mg/l, and 5.1 mg/1 - while below the daily maximum limit,
were high enough to cause a monthly average violation. It is important to understand that the
assimilative capacity of the stream increases with increased stream flow. This situation occurred during
a period when stream flows were significantly higher than the stream flows used to derive the permit
limits [e.g. drought condition flow(7Q10)]. Thus, while not absolving the issues related to the
performance of the treatment plant, the assimilative capacity of the receiving stream was sufficient to
assimilate the additional ammonia loading.
In addition, to the monthly average violation, the operator failed to record a dissolved oxygen result for
the week of 4/26 - 5/2. In response to this violation, the operator was interviewed and additional
training and protocols have been implemented to both help the operator and allow for additional review
so that this type of violation does not occur in the future.
The actions taken demonstrate our commitment to being a good neighbor, as it is always the goal of
Quail Acres Mobile Home Park to remain in compliance with regulations set forth by the Division of
Water Resources. It is our request that our cooperation and action in these matters be considered by the
Division when proceeding with enforcement.
Sincerely,,

Lee Simaan
CC:
Robert White, Envirolink
Joshua Powers, Envirolink