How to Dispose of Photo and X-ray Processor Waste

• Method 1: Collect and dispose of silver-rich spent solutions as hazardous chemical waste.
  • Follow the instructions on How to Store and Dispose of Hazardous Chemical Waste.
• Method 2: Have silver-rich spent solutions hauled off-site for recovery or disposal by an approved outside vendor.
• Method 3: Silver-rich spent solutions may be treated on-site at UCSD and poured down the drain, either by a service company or by the department. If you choose an on-site method of disposal, you must do the following:
  • Contact the EH&S Environmental Management Facility, (858) 534-2753.
  • Request written acknowledgement of your treatment and disposal method (2 options are decribed below).
  • Keep the acknowledgement near the process location for review by San Diego County wastewater inspectors.
  • Select 1 of the 2 options below for on-site silver recovery and disposal.
    • Option 1: Have a service company perform recovery and drain disposal.
    • Option 2: Perform silver recovery and drain disposal yourself.
  • Make sure these requirements are met, whether using a service company (Option 1) or performing silver recovery yourself (Option 2):
    • Date all chemical recovery cartridges (CRCs) when first placed into service with a permanent marker.
    • Follow the instructions below appropriate to your equipment and the quantity of silver-rich solution generated:
      • If an average of less than 0.5 gallons per day is generated, use a single CRC with manufacturer-specified flow control to treat the silver-rich solution.
      • If an average of 0.5 to 20 gallons per day is generated, use 2 CRCs in series with manufacturer-specified flow control.
      • If an average of more than 20 gallons per day is generated, use 1 of the 2 methods below:
        1. Use an electrolytic unit, plus 2 or more CRCs with manufacturer-specified flow control.
        2. Use an electrolytic unit, plus a precipitation unit.
    • Test effluent using silver test paper at least every 3 months. Contact the EH&S Environmental Management Facility, (858) 534-2753, for more information about test paper.
    • Install fresh cartridge(s) when test paper turns black.
    • Dispose of the solution down the drain when the test paper result is less than 5 ppm.
    • Keep test results with your treatment acknowledgement available for review by county inspectors.
      • If using a service company, have tests performed every 3 months, with results provided to the department.
      • If the department performs testing, keep a log of test results, signed by the person who performs the test.

Spent developer solutions from most photo processing units can be discharged to the sewer after it's confirmed that they are non-hazardous.

• Check How to Identify Hazardous Chemical Waste to see if your solution's concentration and quantity is hazardous or non-hazardous.
• If your solution is non-hazardous, pour it down the drain.
• If your solution is hazardous, dispose of it as hazardous chemical waste.

These items are usually hazardous waste.

• Check How to Identify Hazardous Chemical Waste to determine if your material is hazardous or non-hazardous waste, and follow appropriate disposal instructions.