FACT SHEETSeptic Systems Permitting in Luna Lake/Alpine - Summer 2008

WATER QUALITY INVESTIGATIONS IN THELUNA LAKE AREA

Alpine is an eastern Arizona community of about 600residents, located in the vicinity of Luna Lake at the junctionof U.S. 180 and U.S. 191. Alpine is just 6 miles west of theArizona-New Mexico border and about 60 miles southeastof Pinetop-Lakeside, Arizona (see map below).

A study published by the Arizona Department ofEnvironmental Quality (ADEQ) in 2000 identified waterquality impairments at Luna Lake. This ADEQ study, knownas a Total Maximum Daily Load (TMDL) study, determinesthe maximum amount of pollutants that a stream or lake canreceive and still meet Surface Water Quality Standards(SWQS). A TMDL identifies the pollutants, the sources ofthe pollutants causing the water quality impacts, and thepotential reductions that would be required for the waterbody to attain and maintain SWQS. The investigation identi-fied the pollutants of concern at Luna Lake as pH, dissolvedoxygen, total nitrogen, and total phosphorous. The studyattributes, in approximate numbers, 36 percent of totalnitrogen entering Luna Lake to septic system discharges, 20percent to agriculture activities, 11 percent to elk herds,and the balance to forestry and other activities. ADEQ isworking with the Arizona Game and Fish Department onimproving management of the lake, including dredging, andwith the Arizona Department of Agriculture and the U.S.Forest Service on improved land management practices.

Septic systems remain a significant contributor of totalnitrogen to Luna Lake that need to be addressed. Highconcentrations of total nitrogen above the regulatory stan-dards have the potential to impact public health and theenvironment, and to spoil the natural beauty of the lake.

This impact could potentially limit the recreational andresidential activities of this pristine area, and have thepotential to lower property values in the area if notaddressed. Luna Lake provides a wide array of recreationalopportunities, and the impacts to these activities, such asboating, fishing, hunting, waterfowl watching and sightseeingwould be impaired if nitrogen loading to the lake is noteffectively controlled.

WHAT IS THE IMPACT OF SEPTIC SYSTEMS ON LUNA LAKE?

Excessive levels of nitrogen and phosphorus introducedinto Luna Lake can increase production of algae and cause arapid growth of lake vegetation. Algal blooms and largeamounts of decaying algae consume oxygen in the lakewater and can cause fish kills. Further, decomposition of thelake vegetation growing as a result of the nutrient inputsconsumes large amounts of oxygen resulting in fish kills, anincrease in pH and consequently formation of ammoniawhich is highly toxic to fish and aquatic life. Excess totalnitrogen can also leach into the groundwater and affectdrinking water wells.

Conventional septic systems use antiquated, 19th centurytreatment technologies. Wastewater enters the first chamberof a septic tank, allowing solids to settle and scum to float(see septic system diagram). Liquid waste flows through adividing wall into a second chamber of the tank wherefurther settlement takes place, with excess liquid thendraining from the outlet into the leach field. From the leachfield, contaminants in the liquid waste seep into the soil andcan negatively impact local groundwater and connected

Publication Number: FS 08-10

surface waters. Conventional septic systems do not adequatelytreat wastewater or otherwise remove contaminants suchas total nitrogen. In contrast, there exist several alternativenitrogen-reducing onsite wastewater treatment systemsthat effectively reduce the nitrogen and bacteria, thus limitingadverse water quality impacts.

LONG TERM MITIGATION STRATEGYADEQ is working with the Apache County Health

Department and the Alpine Sanitary District (proposed to bethe Alpine Domestic Water Improvement District), to put inplace regulatory measures that would restrict the amount ofnitrogen discharged in or near Luna Lake and the SanFrancisco River. The long term goal is to reduce the totalnitrogen impact from septic systems by connecting as manyresidential and commercial facilities to the sewer collectionsystem for the District’s wastewater treatment facility aspossible. The Alpine DWID is currently developing a sewermaster plan that will allow many previously unsewered areasin the region to be connected to sewer and to limit furthernitrogen discharges.

INTERIM MITIGATION STRATEGYADEQ is currently recommending that any new develop-

ments in the Luna Lake area be connected to the existingsewer collection system if possible. If the opportunity toconnect to sewers is not available, any new septic systemsshould incorporate the use of nitrogen reducing technologiesto limit the impacts to Luna Lake. This voluntary effort to

adopt nitrogen-reducing onsitewastewater treatment systemsinstead of traditional septic systemswill require the cooperation of theentire community, including lotowners and developers. Thereview and permitting of all nitro-gen-reducing onsite wastewatertreatment systems in the pre-scribed assessment area definedby ADEQ (see Alpine region mapon left) will be conducted byADEQ. Please send all applica-tions for such permits within thisassessment area to:ADEQ: Water Quality DivisionEngineering Review Desk1110 W. Washington St.Phoenix, AZ 85007

All permit applications mustinclude the appropriate form, feeand a detailed site investigationperformed by a qualified person

that incorporates the following information:

• Slopes, rock outcropping, and fill material

• A floodplain analysis

• A setback analysis

• Appropriate system selection

• Soil characterization (down to 12 feet)

• Percolation test method

• Seepage performance test method

• Seasonal high water table data

The ADEQ site investigation form can be obtained atwww.azdeq.gov/environ/water/permits/download/investigation.pdf

ADEQ CONTACTS

Byron JamesCommunity Liaison(928) 337-3565 E-mail: bfj@azdeq.gov

David BurchardManager, Wastewater & Subdivision Unit(602) 771-4298 E-mail: db2@azdeq.gov

Web site: www.water.azdeq.gov