California Department of Resources Recycling and Recovery (CalRecycle) 

Compostable Materials

Example Odor Complaint Investigation Procedures

The following suggestions are for informational purposes. The Complaint Response and Odor Monitoring procedures were developed by Riverside Co. LEA and are over 10 years old. The LEA no longer uses these procedures because the monitoring had no effect or usefulness on preventing or reducing the odors. In the case of Riverside Co. LEA's experience, the climate had the greatest effect. Riverside Co. LEA also found that it was difficult to determine the difference in the odor on a 1- 5 scale especially between "2", "3" and "4" . However, the odor monitoring and complaint response procedures below may offer a framework for a LEA that wishes to create a program to respond to odor complaints or for verification that a site's Odor Impact Minimization Plan is effective.

Odor Complaint Response Procedures

Responding to complaints should have top priority over any other routine work. 

Whether “on-call” or conducting an odor monitoring circuit you must respond to an odor complaint as soon as practicable.

When you arrive at the location from where the complaint was called in you should immediately contact the complainant(s) to verify the presence of the alleged odor and make the following determinations:

Is there an odor at the location?

If yes, ask the complainant if it is the odor that prompted him/her to call in the complaint.

If no, ask the complainant if they still detect the odor. It may be advisable to stay in the vicinity for a few minutes to allow for a change in the wind direction to see if the odors return. If the complainant insists that they detect the odor but you cannot detect it record this information in your complaint report. Discretely let the complainant know that you cannot detect the odor.  Conclude the complaint investigation.

Is the odor, in your best estimation, attributable to a compostable materials handling site?

If yes, document your observations and estimate the wind direction using your magnetic compass. Conduct your observations in the following manner.

Is the complaint location downwind from the compostable materials handling site?

Check the vicinity downwind from the complaint location for potential odor sources.

Check known potential odor sources that are upwind from the complaint location and from the compostable materials handling site that may be contributing to the odor event. (Other potential odor sources are the underlined stops on the odor circuit form.)

If the complaint occurs during normal business hours, proceed to the compostable materials handling site and notify responsible on-site personnel of the verified complaint.

Record the activities that were taking place at the time the complaint was registered.

If complaint can be attributed to the compostable materials handling site, document in the report how you came to this determination. Include wind direction in your report.

Is the odor not attributable to the compostable materials handling site?

What characteristics about the perceived odor cause you to believe it to be from some other source?

What is the wind direction? Is the wind from some other direction than the compostable materials handling site?

If the odor cannot be attributed to the compostable materials handling site refer the matter to the local Air District.

Odor Monitoring Procedures--Conducting An Odor Monitoring Circuit

The following procedures shall be addressed when conducting the odor circuit:

  • A route should be established with designated stops for monitoring odors around a compostable materials handling site that has received odor complaints. The route should include locations within the alleged impacted neighborhood as well as close to the compostable materials handling site.
  • The time, odor intensity, odor characteristics (type of odor), and wind direction should be recorded at each monitoring location. Even if odors are not detected indicate the time and wind direction regardless of the presence of odors. The odor intensity may be a 0-5 scale with 0 being “non-detected” and 5 being extremely intense. The odor characteristics may be a short list of words such as “rotten eggs, musty, ammonium etc” which could be circled when applicable and/or a blank space to allow for a description of the odor.
  • All inspectors should use the same log when recording data during odor monitoring circuit. The log should include space for the time, numerical codes for odor intensity and a small list of odor characteristics or a blank space, and a space for wind direction.
  • If the odor intensity is 0 or “not detectable” then it is assumed that the odor characteristic is “N/A”. Results should be documented completely even though it may seem unnecessary or repetitious.
  • The results of the odor circuit at each location may be entered into a database if there are numerous complaints so that the information may be analyzed and available to the public and the site operator.
  • The inspector’s vehicle should be shut off so that exhaust fumes do not influence the ability to detect odors. Exhaust or dust from nearby vehicles should be cleared before conducting the odor monitoring at the location.
  • If a magnetic compass is being used to determine wind direction, the inspector should stand at least ten feet away from the vehicle to assure that the metal does not deflect the compass’ needle reading. Also, other metal objects such as clipboards, flashlights and overhead power lines may effect the compass and should be avoided when taking a reading.
  • At least two to three minutes should be spent at each stop on the odor monitoring circuit to allow for minor wind shifts that may transport odors either toward or away from the location.
  • Important: If an inspector discovers an odor attributable to the compostable materials handling site, the operator of the site should be notified immediately. The odor impact minimization plan must be reviewed and revised as necessary.
  • If citizens approach an inspector while conducting the odor monitoring circuit to complain about the odor at that location, the citizen’s complaint should be taken in the field by the inspector regardless if the inspector verifies the odor at that location.

The following equipment should be available when conducting an odor monitoring circuit:

  1. Odor Monitoring Log Sheet
  2. Magnetic Compass
  3. Cellular Phone and phone number(s) of the compostable material handling sites
  4. Flashlight (for nighttime evaluations)
  5. Complaint Form in case citizens are in the area and approach the inspector to make a complaint

Odor Complaint Investigations | Odor Home

Last updated: October 30, 2008
Compostable Materials, http://www.calrecycle.ca.gov/SWFacilities/Compostables/
Martin Perez: Martin.Perez@calrecycle.ca.gov (916) 323-0834