let's just dump the sewage on the ground

Sanitary district discontinuing septic waste and grease disposal
By Teresa McQuerrey, Roundup staff reporter
Friday, April 4, 2008
The Northern Gila County Sanitary District has plans to discontinue the receiving of septic and grease trap wastes at its facilities on July 1. This change will result in homeowners with septic tanks and businesses with grease interceptors spending more money for their disposal needs.
For 20 years the district has accepted these waste materials at its facilities, but with the area's population growth, a need to preserve treatment plant capacity, the potential for adverse impact on the district's facilities and compliance with regulations and permits has forced the change.
Joel Goode, general manager, said the Buckhead Mesa Landfill's operating permits from the state and federal government don't allow it to take liquid waste. It was because of those restrictions the sanitary district board agreed to provide disposal services.
The district and septic haulers have had yearly agreements to accommodate the waste material, but as of June 30, those agreements will not be renewed, Goode said.
He said the way waste is intended to decompose in a septic system and the manner in which that same waste is processed in the plant are incompatible. The septic wastes add tremendous load or demand on the system. In order to put the septic waste into the plant's treatment process, extra steps and treatment components are needed. Waste from grease trap interceptors is put in drying beds to eliminate enough moisture for it to be acceptable material at the landfill. This process is labor intense and costly, Goode said. Currently the district dries and hauls the material to Waste Management's transfer facility for disposal off-site in its private landfill, he said. Business owners will need to explore all the alternatives of grease disposal, Goode said.
The district is assisting Gila County and the local haulers explore alternatives to lessen the economic impact to residents and businesses.

I remember well when the City of Phoenix (COP) took a similar course of action some years ago and closed their septage receiving facility located at their 23rd Ave wastewater treatment plant (wwtp). At this time I operated a septic pumping operation so this action had a definite impact upon not only me but my customers and numerous other septages pumping companies’ state wide that relied upon this COP facility for the lawful disposal of septage. I underline lawful as I will return to its salient importance a bit later. COP took this action after spending millions of your tax dollars to upgrade and put into operation that at the time was a “state-of-art” septage receiving facility which included a reasonably accurate “cradle to grave” reporting format.

It is quite understandable in an era when all municipal as well as quasi-public-private wastewater treatment plants are facing increased challenges on many fronts, financial as well as the volume, types and strength of sewage they are required to treat that eliminating a vexing source such as septage from their mix is a course they would certainly consider.

There is no denying that addition of septage as a portion of the sewage which smaller sewage treatment facilities receive increases their operational challenges. Correspondingly it makes it far more difficult for them to achieve the “magic” sewage discharge parameters established by EPA, et. al. That these “magic” sewage discharge parameters are solely the result of backroom deal making between regulators, vendors, for-profit-operators, politicians, consulting engineers and selected academia is a topic for another day. “We” – that’s you and me – and Green Peace and other proactive environmental groups are not invited to these backroom inner-sanctum dealing making activities. Care to speculate why…?

Everyone needs to be made aware that all sewage treatment plants regardless of size, configuration, location, treatment process utilized are designed based upon conditions deemed appropriate for that environment by regulators, engineers, contractors, politicians. Again, you and I are not asked to be part of that equation. The usual and customary parameters for municipal sewage treatment plants principally designed to accept residential sewage is in the range of 500 mg/l of BOD influent (and I’m being generous). This is an agreed upon technical measure used to determine the strength of the sewage which the facility is designed to treat to the appropriately predetermined sewage discharge level. Another piece of data is valuable to you. Residential sewage usually ranges from 200 – 300 mg/l, so I am being quite conservative with my 500 mg/l design parameter. In fact I am being extremely generous as older facilities were designed at the upper parameter of 300 mg/l. Another factor which will assist you in understanding this discussion is that most normal residential sewage is treated based on the introduction of a specified amount of oxygen over a specified amount of time predetermined to reduce its “strength” and other constituents to a level permitting discharge into the ground or a receiving water body.

Here’s the “kicker” as septage in the form of septic tank waste and liquid from commercial restaurant grease traps, car washes, laundry lint interceptors, etc have an influent strength exponentially greater than normal residential sewage. This increased strength contained in a small volume creates for the operators of smaller wastewater treatment facilities, in particular, appreciable headaches resulting in noncompliance and exceeding their discharge parameters and greater operating costs.

So, on the one hand it can make clear economic and financial sense to eliminate, if possible, all forms of septage from any small wastewater treatment plant. And, why do I keep emphasizing small…? Well, here’s another factor which – you’re – not suppose to know. One rather simple way to negate the distortion created by the introduction of septage into any sewage treatment plant is to either meter it over time or dilute it in a substantively greater quantity of relatively “weak” sewage. In either case … “dilution is the solution” … though were you to mention this as a form of treatment to any regulator, engineer, plant operator they would immediately scoff and rebuke you. But don’t kid yourself its employed everyday worldwide, including here in Arizona.

But the salient point is, if “we” do not want septage to be disposed of and treated in our current existing wastewater treatment facilities, where do “we” want this form of liquid waste – lawfully – to be disposed of and properly treated. Returning for a moment to the days prior to the closure of the COP 23rd Ave WWTP one provision they imposed, which at first the industry fought, was a “manifest” system. Every load disposed of at this facility noted the name and the location of the generator (the site where this liquid was pumped), the amount, the date, and the type of sewage. Then each load was initially tested for pH as well as certain standard factors before the load could be disposed of into the COP receiving facility. During this period of time appreciable attention was being paid on many fronts including by industry itself to “illegal” (desert dumping) or the omnipresent “mid-night” dumpers into city manholes, etc. This universal manifest system utilized by both the COP and Maricopa County was instrumental in beginning to “clean up” what at one time was a pirate dominated industry.

The COP facility closed, most notably in response to political pressure by former owners of the Phoenix Suns. These gentlemen opened their “for-profit” receiving facility, which coincidentally still dumps its residual effluent into the COP waste stream going to the COP 91st Ave wwtp. Since then other “for-profit” facilities have opened all of whom dump their residuals into sewer lines terminating generally at the 91st Ave wwtp operated by the COP.
So, I ask again, if “we” don’t want septage to be lawfully disposed of in our wwtp, where do “we” want it to be disposed…? In lieu of providing a lawful disposal site for septage, we are only encouraging a return to “illegal” dumping and disposal…?

In the final analysis the choice is clearly in our hands.