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Dental Offices

Dental Office Regulations

On June 14, 2017, the United States Environmental Protection Agency (USEPA) promulgated pretreatment standards to reduce discharges of mercury from dental offices into publicly owned treatment works (POTWs). The Dental Office Category regulation is codified at 40 CFR Part 441.

All dental offices within the DELCORA service area that place or remove amalgam must operate and maintain an amalgam separator and must not discharge scrap amalgam or use certain kinds of line cleaners.  Please note, this regulation applies to all dental offices that may not be direct customers of DELCORA but whose wastewater ultimately flows to DELCORA for treatment.

The amalgam separator must comply with one of the following:

  • American National Standards Institute (ANSI) American National Standard/American Dental Association (ADA) Specification 108 for Amalgam Separators (2009) with Technical Addendum (2011)
  • International Organization for Standardization (ISO) 11143 Standard (2008)
  • Subsequent versions – as long as the separator achieves at least 95% removal efficiency

The following offices are exempt from installing an amalgam separator:

  • Offices that exclusively practice at least one of these specialties: oral pathology; oral & maxillofacial radiology; oral & maxillofacial surgery; orthodontics; periodontics; prosthodontics
  • Mobile dental units or offices that discharge wastewater into a private septic system
  • Offices that do not place amalgam and only remove amalgam in limited, emergency or unanticipated circumstances (estimated less than 5% of procedures per year)

Offices with installed amalgam separators are also required to comply with the following:

  • Monitor the separator according to manufacturer’s guidelines
  • Inspect separators at least once a month to ensure proper operation and maintenance of the separator
  • Replace/Repair any malfunctioning separators according to manufacturer instructions within 10 business days of discovering the defect
  • Maintain separators by replacing amalgam retaining cartridges, separator canisters or units as directed by the manufacturer, or annually, whichever comes first
  • Do not discharge waste amalgam from chair-side traps, screens, vacuum pump filters, dental tools, cuspidors, or collection devices to a POTW. In other words, no flushing waste down the drain.
  • Do not use oxidizing, acidic cleaners when flushing dental unit water lines, chair-side traps and vacuum lines. Do not use bleach, chlorine, iodine or peroxide cleaning agents that have a pH of lower than 6 or higher than 8.
  • Install the separator unit so that it receives all amalgam process wastewater and that it is sized to incorporate all wastewater than may pass through it.

In addition, dental practices must retain any records of the following for a 3 year time period:

  • Any reports filed
  • Visual inspection log – including the date, person(s) conducting the inspection, the results of each inspection and a summary of follow-up actions (if needed)
  • Any repair or replacement- including the date, person(s) making the repair/replacement, a description of the repair/replacement and documentation of the amalgam retaining container replacement (including date)
  • Disposal records – including all dates that collected dental amalgam is picked up or shipped for proper disposal, and the name of the permitted or licensed treatment, storage or disposal facility receiving the amalgam retaining containers
  • Manufacturer’s current operating manual for the device in place

To verify compliance with this requirement, DELCORA has developed a mandatory one-time compliance reporting form that must be submitted by all new and existing dental offices.  Once the form is completed and returned to DELCORA, the DELCORA pretreatment staff will evaluate its completeness to determine the need for follow-up evaluation and/or an onsite inspection.  Completeness of this form is imperative and failure to submit may result in further regulatory oversight and requirements.  A copy of the one-time compliance reporting form must also be retained onsite.

Dental offices existing before June 14, 2017 that are subject to this regulation must achieve compliance no later than July 14, 2020.  Newly constructed or purchased dental offices established after July 14, 2017, must have achieved compliance immediately and submit a one-time compliance report no later than 90 days of operation.

For more information, please contact the DELCORA pretreatment department via email at

Additional References

The Academy of General Dentistry: Read More Here »

The American Dental Association (ADA): Read More Here »

United States Environmental Protection Agency (USEPA): Read More Here »

Compliance Awards Program

Compliance Awards Program (CAP)

The Compliance Awards Program (CAP) was established to recognize those DELCORA pretreatment permittees with exemplary compliance and, by doing so, ultimately help DELCORA achieve our mission of providing environmentally responsible and cost effective wastewater management services.  Please download the COMPLIANCE AWARDS PROGRAM form for information.

Compliance Awards Program Form



Do I need a Wastewater Discharge Permit?

  • Not every industrial discharger is required to have a permit, but all dischargers must be in compliance with the DELCORA Standards, Rules and Regulation of 2011 (Resolution No. 2011-04). Permits are issued to the following commercial and industrial facilities:
    • Federally regulated industries (Categorical Industrial Users). These industries are subject to technology-based limitations on pollutant discharges to POTWs promulgated by EPA in accordance with Section 307 of the Clean Water Act that apply to specified process wastewaters of particular industrial categories [see 40 CFR 403.6 and 40 CFR Parts 405- 471]. Go to
    • Dischargers with volumes of process wastewater greater than 25,000 gallons per day (Significant Industrial Users).
    • Any discharger with the potential to negatively impact the sanitary sewer system.
  • If you fall under these conditions, you must obtain a wastewater discharge permit or submit a wastewater discharge permit application. If you are unsure, submit a wastewater survey to the DELCORA Pretreatment Department for evaluation. 


What does the wastewater discharge permitting process entail?

  • Complete a wastewater survey and application. Once the application is submitted, a fee will be invoiced for processing the application. After receipt of the fee, the pretreatment department will begin its assessment of the application and will issue a draft permit. The pretreatment staff may do on-site evaluation of the physical address to verify reported information and determine needs. The final permit will be issued following a 30-day comment period.


How long does it take to obtain a wastewater discharge permit?

  • The permitting process takes approximately 1.5 – 5 months, depending on the completeness of the application and the complexity of the industrial processes on site.


Are there any fees associated with the permitting process?

  • There is a permit application fee, which is assessed with new permits and permit renewals. Additionally, there is an annual maintenance fee for pretreatment services. Please see Resolution No. 2014-11 for the most current fee schedule. This Resolution also establishes fees for permit modifications and temporary permits.


What are your discharge limits?

  • DELCORA is divided into two sewer service areas and discharge limits are specific to the wastewater treatment plant that an industry’s wastewater flows to. See discharge limits/regulations.


What is the difference between a “West” and “East” industrial user?

  • The Industrial Users in the West discharge wastewater to the DELCORA Western Regional Treatment Plant located Chester, Pennsylvania and Industrial Users in the East discharge wastewater to the City of Philadelphia Southwest Water Pollution Control Plant located in Philadelphia, Pennsylvania.  Industrial Users are subject to different local limits depending the West or East designation because the local limits are specific to each facility.  To view a list of municipalities and the respective West and East designations, click here.


In the event of a spill or a process upset, who should I contact?

  • DELCORA should be immediately notified of any spill or process upset affecting the sewer system. Please notify the shift foreman at 610-876-5523, extension 214 (24 hours/day) and the Pretreatment Manager at 610-876-5523, extension 213 (8:30AM – 4:30PM).


Where can I dispose of groundwater from excavation or remediation projects?

  • Groundwater from remediation projects is not allowed into the sanitary sewer unless approved by DELCORA. Groundwater can be disposed of in the sewer after obtaining a permit from the DELCORA Pretreatment Department. If the project is outside the City of Chester or Marcus Hook’s jurisdiction, you must contact the local municipality for additional approval.


I have an industrial wastewater discharge permit. When are my reports to DELCORA due?

  • Monthly reports are due on the 28th day of the following month (i.e. July’s self-monitoring report is due August 28th).
  • Quarterly reports are due on the 28th day of the month following the completion of the quarter (i.e. 2nd quarter report is due July 28th).
  • Semi-annual reports are due on the 28th day of the month following the completion of the reporting period (i.e. January through June reports are due July 28th).


I have an industrial wastewater discharge permit. What Laboratory should I use for my self-monitoring requirements?  

  • The DELCORA Standards, Rules and Regulations of 2011 (Resolution No. 2011-04, Section 327) prescribes that all analyses be conducted at an accredited PADEP or NELAC accredited laboratory with demonstrated competency in water and wastewater testing. While DELCORA does operate an accredited laboratory onsite at the POTW, these laboratory services are not available to industrial users.


I have an industrial wastewater discharge permit and I just became aware of a permit violation. What should I do next?

  • If the results of the Permittee’s wastewater analysis indicate an effluent limit exceedance has occurred, the Permittee must:
    • Inform DELCORA of the violation within 24 hours of awareness of result; and
    • Repeat the sampling and pollutant analysis and submit, in writing, the results of this second analysis within thirty days of becoming aware of the first violation.
  • The industrial user is not required to resample if:
    • The Control Authority performs sampling at the industrial user at a frequency of at least once per month.
    • The Control Authority performs sampling at the Permittee’s location between the time when the Permittee performs the initial sampling and the time when the Permittee receives the results of this sampling.


Local Limits for Discharge at DELCORA Facilities: This document describes local limitations and substance restrictions for discharge to DELCORA facilities under the industrial pretreatment program.

DELCORA Standards, Rules, and Regulations of 2011: This document details standards, rules, and regulations governing the proper disposition of all wastewaters introduced into the DELCORA wastewater management system, including: the acceptance and connection to DELCORA facilities; establishing the procedures, enforcement provisions and fee system to administer the regulations; and other related matters.

United States Environmental Protection Agency (EPA) Pretreatment Program: This link will take you to the website for the National Pretreatment Program under EPA’s National Pollutant Discharge Elimination System.

Pretreatment Forms

Please download the appropriate Pretreatment Forms. Please submit completed forms by email to pretreatment@delcora.orgor by mail to:

Attention: Pretreatment
P.O. Box 999
Chester, PA 19016-0999


Self-Monitoring Checklist East – A form to assist permitted Industrial Users in the Eastern Service Area to ensure compliance with the monitoring requirements of the industrial discharge permit.

Self-Monitoring Checklist West – A form to assist permitted Industrial Users in the Western Service Area to ensure compliance with the monitoring requirements of the industrial discharge permit.

 Industrial User Survey – A form that enables DELCORA to evaluate any potential industrial users that may require permitting under DELCORA’s pretreatment program.

Site Inspection Form – DELCORA performs routine inspections of permitted industrial users using this form.

Spill Slug Form East – Every permittee in the Eastern Service Area is required to develop a Spill/Slug Prevention Plan and this form assist industrial users fulfill the specific conditions detailed in every wastewater discharge permit.

Spill Slug Form West – Every permittee in the Western Service Area is required to develop a Spill/Slug Prevention Plan and this form assist industrial users fulfill the specific conditions detailed in every wastewater discharge permit.

Wastewater Discharge Permit Application – The application required by DELCORA to evaluate industrial users and to subsequently issue site specific wastewater discharge permits.


Program Overview

DELCORA’s Industrial Pretreatment Program (IPP) was established in accordance with the Clean Water Act (CWA) to fulfill the following objectives:

  • To prevent the introduction of pollutants into Publicly Owned Treatment Works (POTWs), which will interfere with the operation of a POTW, including interference with its use or disposal of municipal sludge.
  • To prevent the introduction of pollutants into POTWs, which will pass through the treatment works or otherwise be incompatible with such works.
  • To improve opportunities to recycle and reclaim municipal and industrial wastewaters and sludges.

To achieve these objectives, DELCORA issues Wastewater Discharge Permits to all significant, categorical, and high impact industrial users prior to discharge. These permits strictly adhere to the regulations and protocols established in 40 CFR 403 and DELCORA Resolution No. 2011-04. This system enables DELCORA to work with industrial users to facilitate compliance and preserve the quality of the Delaware River Estuary.