Water Quality Division: Permits: Aquifer Protection Program (APP): Frequently Asked Questions (FAQ)

Aquifer Protection Permit (APP)

How can I get my permit faster?

We encourage all applicants to meet with us before submitting an application to resolve issues that may arise early in the process. Permits can be processed more quickly if an application is submitted that is complete and technically sufficient to meet program requirements. You also have the option to request a review of your application by a consultant under contract to ADEQ.

Will ADEQ help me determine if I qualify for a general permit or exemption?

The department will help you determine if the facility qualifies for a general permit or exemption upon request. The first step is to fill out the Determination of Applicability Form (Revised 07/15/2011) (Word) (PDF). The application fee is $2,000 per request and is non-refundable. Maximum fee is $15,000 as specified under A.A.C. R18-14-102 & 103.

Do I need a permit to close my facility?

Clean closure plans may be approved by ADEQ without issuing a permit for drywells, and facilities that have aquifer protection permits, groundwater protection permits or a notice of disposal on file with the department.

What must be demonstrated to get an individual permit?

There are numerous requirements specified in 18 A.A.C. 9, Article 2. However, the following are the most critical:

  1. BADCT - The applicant must show that the best available demonstrated control technology (BADCT - pronounced "bad cat") will be used by the facility.
  2. The applicant must show that aquifer water quality standards will not be violated in the aquifer at a point of compliance as a result of discharge from the facility. If the level of a pollutant in the aquifer already exceeds the AWQS at the time of permit issuance, the aquifer must not be further degraded.
  3. Financial and technical capability.

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What is a drywell?

A drywell is a bored, drilled, or driven shaft or hole whose depth is greater than its width and is designed and constructed specifically for the disposal of stormwater.

Who needs to register the drywells?

A person who owns an existing or proposed drywell must register the drywell with ADEQ. Persons registering a drywell must complete a Drywell Registration Form supplied by ADEQ, and submit a registration fee of $100 per drywell. Drywells used in conjunction with golf course maintenance do not need to be registered as they are exempted from regulation under the drywell program. However, any vadose zone injection wells (including drywells) that receive stormwater mixed with reclaimed wastewater or groundwater, or both, from manmade bodies of water associated with golf courses, parks and residential areas must be registered. In this situation, a general permit is issued by statute in lieu of an individual permit, provided that six criteria, including registration, are met (A.R.S. § 49-245.02).

How are drywells regulated?

Drywells can only receive stormwater runoff or discharges that are exempted by A.R.S. § 49-250(23). If other fluids have been directed to the drywell, it is subject to the Aquifer Protection Permit (APP) and/or closure requirements and may be considered an underground injection well that requires both ADEQ and U.S. EPA permitting. Spills to the drywell may also trigger permitting, clean closure or enforcement actions.

Regulations governing drywell operation, etc. are found in A.R.S. § 49-331 through 49-336 (laws regulating drywells), A.R.S. § 49-201(5) (clean closure definition), A.R.S. § 49-241 (permit required to discharge) and A.R.S. § 49-245.02 (general permit for certain discharges associated with manmade bodies of water).

An APP is required for any drywell located in an area where hazardous substances, including motor fuels, are used, stored, treated or loaded. The permitting requirement may not apply if the site plan clearly demonstrates that the site is graded or engineered such that drywell(s) can not receive runoff or spills from chemical handling areas.

For other aspects of the drywell program, the agency has developed guidance which should be followed for drywell construction, maintenance, siting, investigation, decommissioning and closure. The available guidance documents are listed below.

When do APP program requirements apply to drywells?

APP program requirements apply to certain drywells and injection wells for operation and closure. An APP is required for drywells draining areas where hazardous substances are used, stored, loaded or treated. If there is question about the status of a drywell, a determination of applicabilty form is available and may be requested to aid in evaluating regulatory requirements.

Also, general APPs are issued to certain drywells by statute, as provided in A.R.S. § 49-245.02. In addition, certain discharges to drywells in combination with stormwater are exempt from the APP requirements. Eight types of discharges other than storm water are listed in statute (A.R.S. § 49-245 and 49-250(23)).

What about drywells in drainage areas where there are hazardous substances?

The APP requirements apply to drywells that drain areas where hazardous substances are used, stored, loaded or treated. An APP is required to ensure that best management practices are followed and hazardous substances are kept from entering the drywells by using the proper engineering design, physical barriers and procedural controls. An APP application requires information about the design of the drywell and development of a Best Management Plan to protect the drywell. The application process also requires sampling of sediment from the settling chamber of the drywell. Generally, initial testing includes TPH, total metals and organic compounds; however, constituents analyzed should be representative of the chemicals or wastes that are or have been used at the site.

What about drywells in other areas?

If a drywell does not drain areas where hazardous substances are used, stored, loaded or treated, APP program requirements typically do not apply. However, unless specifically exempt by statute, if a facility adds any pollutant to a drywell, it may be classified as an injection well and be subject to permitting. Any drywell that is used for industrial wastewater disposal, either solely or in conjunction with stormwater discharge, is an injection well. APP program requirements apply to operation or closure of injection wells. You should contact the ADEQ Industrial and Drywell Unit if hazardous substances have been detected in your drywell, if unauthorized disposal of waste into the drywell has occurred or if spills of hazardous substances have entered your drywell.

What if I want to close a drywell?

If a facility proposes to close a drywell that has drained areas where hazardous substances are used, stored, loaded or otherwise managed, a clean closure application must be submitted to ADEQ for approval. If the facility can demonstrate clean closure of the drywell per ARS § 49-252, an APP will not be required.

For drywells that have not drained such areas but that have received unauthorized spills, ADEQ may request a clean closure application that addresses necessary investigation and remediation.

A drywell that has never drained areas where hazardous materials have been managed and has received only stormwater discharges can be closed at any time.

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Direct Use of Reclaimed Water

When do I need to get a permit?

You need to obtain a reclaimed water individual permit or reclaimed water general permit if you are:

  • An owner or operator of a sewage treatment facility that generates reclaimed water for direct reuse
  • An owner or operator of a reclaimed water blending facility
  • A reclaimed water agent
  • An end user
  • A person who uses gray water
  • A person who directly reuses reclaimed water from a sewage treatment facility combined with industrial wastewater or combined with reclaimed water from an industrial wastewater treatment facility
  • A person who directly reuses reclaimed water from an industrial wastewater treatment facility in the production or processing of a crop or substance that may be used as human or animal food

Are there other requirements?

All wastewater treatment facilities providing reclaimed water for reuse must have an individual Aquifer Protection Permit (APP), or amend their existing APP to contain certification for a particular class (A+, A, B+, B, or C) of reclaimed water. The APP requires monitoring and reporting of reclaimed water quality to ensure that effluent limitations for reclaimed water quality classes are met.

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Biosolids Frequently Asked Questions

What are biosolids and why are they useful?

Biosolids are nutrient-rich organic by-products resulting from wastewater treatment that can be beneficially recycled. They are not raw human waste. At the wastewater treatment plant, solids are separated from the wastewater and transformed into biosolids through the use of physical, chemical, biological and heat processes. These processes reduce the levels of odor and bacteria in the final product, which undergoes testing to ensure effective treatment before it can be used.

Because biosolids contain essential plant nutrients and organic matter, they can be recycled and added to the soil to increase plant production. Plant nutrients are released gradually as the plants need them during the growing season. Organic matter allows soil to breathe as well as hold more water, which results in decreased water runoff and soil erosion. Currently, 46 states, including Arizona, allow for the beneficial re-use of biosolids in agriculture, forestry, and soil improvement projects. Arizona, also allows the use of biosolids to reclaim open mines and gravel pits. Besides application on farm land, other uses of biosolids include application at plant nurseries, parks, golf courses, home lawns and gardens, and highway medians.

In order for biosolids to be used, they must undergo extensive treatment that has resulted from years of scientific research. They must also meet state and federal quality standards for safe application. The amount of treatment depends on what types of biosolids are being applied. Before biosolids may be land applied, the preparer or applicator must treat the biosolids to reduce pathogens (disease causing organisms) and vector attraction (disease-carrying creatures). Exceptional quality biosolids are biosolids that have been treated with a Class A pathogen reduction method and a vector attraction reduction method and meet pollutant concentrations for 10 metals specified in A.A.C. R18-9-1006, R18-9-1010, and R18-9-1005, respectively. Because of the extensive treatment, exceptional quality biosolids, in most cases, are not subject to state requirements for management practices or site restrictions. Biosolids that are not exceptional quality biosolids must have been treated using either a Class A or B pathogen reduction method and a vector attraction reduction method unless the applicator takes steps to reduce the attraction for vectors. Biosolids that are not exceptional quality biosolids are subject to management requirements and site restrictions such as application setbacks, buffer zones and tilling into the soil soon after application. Treated biosolids have significantly fewer pathogens than animal manure.

How many application sites are in Arizona?

Biosolids were applied to approximately 200 application sites within Arizona during 2000. These sites compose more than 11,000 acres.

When were federal biosolids regulations developed?

U.S. EPA first developed biosolids management regulations under the 1972 Federal Water Pollution Control Act. In 1977, Congress amended the act to develop regulations containing guidelines to identify alternatives for biosolids use and disposal, identify concentrations of pollutants that would interfere with each use and specify what factors must be accounted for in determining the methods and practices applicable for each identified use. In 1987, Congress established a timetable for developing biosolids use and disposal guidelines. U.S. EPA promulgated the standards for the use and disposal of sewage sludge (Code of Federal Regulations, Title 40, Part 503) in 1993.

When were Arizona biosolids regulations developed?

Arizona's rules on biosolids (18 A.A.C. 9, Article 10) initiates standards to be used when biosolids are applied to the land as a fertilizer or a beneficial soil amendment. The standards establish biosolids quality and management practices that protect the public health and the environment.

ADEQ registers sites using the applications submitted by people who wish to apply biosolids. ADEQ also reviews annual reports submitted by the applicators to ensure compliance with state rules and responds to public inquiries about the use and application of biosolids. Biosolids annual reports are due to ADEQ by February 19 of each year.

How do I register to apply biosolids in Arizona?

Those interested in applying biosolids in Arizona must complete a biosolids land application and supplemental request form. In addition to the information on the form, the applicator must submit proof of public notice of the potential use of the site for land application of biosolids. See A.A.C. R18-9-1004(C)(5)(g).

Biosolids Land Application and Supplemental Request Form

The applicator must complete and submit the form to ADEQ and receive registration notification from ADEQ before applying biosolids on any land application sites. The completed registration package must be submitted to:

Arizona Department of Environmental Quality
Biosolids Coordinator
Water Quality Division - Water Quality Compliance Section
1110 West Washington Street
Phoenix, Arizona 85007

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What is pretreatment?

Pretreatment is any biological, chemical, or physical treatment process applied to an industrial wastewater stream before it is mingled with sanitary wastewater and/or released into a sanitary sewer collection system for ultimate treatment at a centralized treatment works. The Arizona Pretreatment Program is based on the federal Pretreatment program described at 40 Code of Federal Regulations (CFR) Part 403. This program applies only to discharges to sanitary sewer collection systems that ultimately reach a publicly-owned treatment works (POTW).

What is an Industrial User?

An industrial user (IU) is a source of indirect discharge (A.R.S. 49-255(4)). Indirect discharge means the introduction of pollutants into a POTW from any nondomestic source that is regulated under the Clean Water Act (A.R.S. 49-255(3)). An IU is any industrial or commercial facility that discharges its "waste water" from industrial or nondomestic processes into the sewer system.

What substances are prohibited from discharging to a sewer?

Prohibited substances to the sewer collection system include: substances with extreme pH, heavily-concentrated metal solutions, solvents, flammable liquids, and toxic chemicals (i.e., pesticides, herbicides).

Why must we have a state pretreatment program?

Pretreatment is an integral component of the federal NPDES permit program and now the Arizona Pollutant Discharge Elimination System (AZPDES) to protect the "waters of the U.S." Pretreatment protects the infrastructure investment (i.e., treatment plant and collection system pipes, pumps, valves and other appurtenances) from physical damage (i.e., corrosion from low pH,); protects the operation & maintenance (O&M) workers health and safety; and protects the centraliralized treatment plant operation process from upset, interference, and/or pass-. Lastly, pretreatment protects the quality of the biosolids produced by the centralized treatment works to meet the standards for beneficial reuse.

What is upset, interference and pass-through?

There are four situations that may require the POTW to initiate a pretreatment program regardless of plant flow rate. In addition to plant upset, interference, and pass-through, the production of a poor quality biosolids that cannot meet beneficial reuse criteria, may each, individually require the POTW to take action to protect the utility from the sewer system users.

The most commonly used secondary treatment processes (activated sludge) at centralized wastewater treatment plants in North America today are biological in nature. Huge populations of microorganisms are concentrated in a controlled environment to remove the pollutants from the wastestream prior to final disposal. Just as in nature, the biological organisms are susceptible to environmental, potentially lethal conditions (i.e., extreme pH, concentrated heavy metals, and toxic chemicals). Should the influent to a biological treatment process exceed the normally satisfactory environment in which the microorganisms thrive, there can be immediate, lethal effects to the biological community, resulting in inadequate treatment.

If the cause lasts for a short duration (i.e., a slug-load release from a batch-release, chrome plating operation), the effect may be at least acute, (the microbe population not being entirely killed off), with recovery occurring. This situation describes a treatment plant process "up-set" condition, and may require a short period (i.e., 7 to 10 days), for the process to recover to its normal treatment efficiency. However, if the influent environmental factors remain outside the normal operational range for an extended period, it becomes a chronic condition, and the microbial population may not recover its normal treatment operational efficiency. In such a situation, the degraded treatment process is said to be experiencing, "interference." Unchecked, this condition may carry-on until the POTW final effluent further degrades and exceeds the permitted effluent limits. When this occurs, the treatment plant has violated its operating permit and is liable for possible ADEQ enforcement actions.

Should the situation include heavy metals or other pollutants such as organic chemicals, the accumulated pollutant concentrations in the biosolids may exceed allowable standards and prevent the beneficial reuse of the biosolids. In some cases, the biosolids accumulated levels of toxic chemicals may even be defined as, a "hazardous waste." The disposal costs for hazardous wastes will likely far exceed the disposal costs for the beneficial reuse for the biosolids.

What will the department do about industrial pretreatment for satellite collection systems?

The department, (through the SPC), is evaluating how these satellite collection systems (sewer collection systems that deliver sewerage from an area outside the political jurisdiction where the centralized treatment plant is located), are being regulated at present by U.S. EPA and other states where the NPDES authorization has already been delegated. The Arizona implementation will be consistent with both the federal and other state-delegated programs. Even with NPDES program approval, Arizona will still refer the issues relative to the tribal lands satellite collection systems to the U.S. EPA, due to their sovereign nation status. Regarding the non-;tribal satellite collection systems such as the Sub-Regional Operating Group (SROG) , the NPDES Permittee (Phoenix) will remain the central focus of the SPC attention. Nevertheless, each of the Multi-Cities operating satellite collection systems (i.e., the cities of Mesa, Tempe, Scottsdale, Peoria and Glendale) in their own jurisdiction, will be evaluated independently by the SPC, for compliance with the requirements of each approved IPP. Each satellite collection system should be subject to the POTW permitted control authority conditions for the treatment provided through either a negotiated permit or contract.

Is there a means to protect the POTW from home-based businesses which may violate pretreatment standards?

ADEQ encourages municipalities to develop an education and outreach program to notify homeowners of the prohibitions. If resources allow, municipalities may wish to set up "monitoring"; programs at key locations in your sewer system to determine the quality of the sewage from isolated areas.

As used in the pretreatment program, is it correct to include "privately owned treatment works" along with "publicly owned treatment works"?

No. Do not include privately owned treatment works in the same category as publicly-owned treatment-works (POTW) when discussing pretreatment. Privately-owned plants do not get the same "privileges"as a POTW. Particularly, the Domestic Sewage Exclusion regarding the receipt of hazardous waste. The generic term of privately owned treatment works can mean the industrial treatment process at an industrial plant as well as the sewage plant at that industry.

A privately owned sewage plant also goes by the generic term, "Treatment works treating domestic sewage"or "TWTDS." "TWTDS" is defined in 40 CFR 122.2 and includes both publicly-owned and privately-owned sewage plants. 40 CFR 403.3(o) defines POTW (Publicly-Owned Treatment Works or "POTW"). This term includes all of the collection system as well as the plant and storage facilities. 40 CFR 403.3(p) defines "POTW Treatment Plant"to mean just the treatment, recycling, and reclamation part of the system, i.e., not the conveyance systems. 40 CFR 122.2 contains definitions for "Publicly-owned treatment works," "Privately-owned treatment works," and "TWTDS." The POTW definition in 40 CFR 122 refers you back to 40 CFR 403. The definition for "Privately owned treatment works" includes the clause, ;not a POTW."

What is the Domestic Sewage Exclusion?

The Domestic Sewage Exclusion (DSE) - RCRA Section 1004(27) - codified in 40 CFR 261.4(a)(1) - provides that solid or dissolved material in domestic sewage is not a solid or a hazardous waste under RCRA. The exclusion allows industries to discharge hazardous wastes to POTW sewers containing domestic sewage without having to comply with many RCRA requirements, such as manifesting and reporting, that otherwise apply to facilities that generate hazardous waste. Moreover, POTWs receiving DSE wastes are not deemed to receive hazardous wastes and, therefore, are not subject to RCRA requirements for hazardous waste treatment, storage, and disposal facilities (TSDFs).

How will the ADEQ define the term, "significant noncompliance" (SNC)?

ADEQ adopted the entire federal pretreatment rule (40 CFR 403) by reference (R18-9-A905 and R18-9-A906). The U.S. EPA defines "significant noncompliance" [40 CFR 403.8(f)(2)(vii)] as, "a violation which remains uncorrected 45 days after notification of noncompliance; which is part of a pattern of noncompliance over a twelve month period which involves a failure to accurately report noncompliance; or which resulted in the POTW exercising its emergency authority under paragraph (f)(1)(vi)(B) of this section." The ADEQ definition is the same as the above U.S. EPA definition.

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