Questions and Answers: In-Vessel Digestion Regulations

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Question 1: Should Enforcement Agencies (EA) and operators respond to verbal and anonymous complaints?

Answer 1: Title 14, California Code of Regulations (CCR), 18302 and 18303 outlines the documentation necessary for a written complaint as well as the criteria for what an odor complaint investigation shall include. Note that CalRecycle considers any complaints received through the CalEPA complaint system or referred in writing to the EA by another agency as written complaints.
The EA may investigate verbal and anonymous complaints at their own discretion. The EA may set their own procedures for handling complaints, as described in regulation and their enforcement program plan.
Operators are required prepare, implement, and maintain a site-specific odor impact minimization plan (OIMP), which includes a protocol for receiving and responding to complaints, and is described in 14 CCR 17863.4 (for compostable material handling facilities and operations) or 14 CCR 17896.31 (for in-vessel digestion facilities or operations).

Question 2: What is the reason for noting an intensity rating on the odor circuit form?

Answer 2: Title 14 CCR 18302(d)(3) describes the requirements for odor complaint investigations. Specifically, subsection (3)(C) states that the EA shall, “document odor characteristics, intensity, and duration at the complainant’s location, the solid waste facility/operation, and other odor sources adjacent to the solid waste facility/operation.”
Documenting odor intensity will help to verify a complaint as well as to develop data on the specific types of odors observed in and around a compostable material handling activity. The data will assist the EA better identify the source of odors and what operational activities contribute to changes in odor intensity.

Question 3: Who has jurisdiction over odors from licensed rendering facilities?

Answer 3: The California Department of Food and Agriculture (CDFA) and local air districts regulate rendering facilities, including animal food manufacturers. They are not subject to solid waste facility regulations pursuant to Title 14 sections 17855 and 17896.6.

Question 4: Who is responsible to inspect odor complaints at rendering facilities?

Answer 4: Odor complaints regarding a rendering activity should be investigated by the local air district.

Question 5: Is there a scenario where an EA can cite a violation for the Odor Impact Mitigation Plan (OIMP) even if there are no odor complaints?

Answer 5: Yes, an EA can cite a violation if they determine that the facility or operation is not following the procedures established in the OIMP pursuant to 14 CCR 17863.4 and 17896.3. All compostable material handling facilities and operations and in-vessel digestion facilities and operations are required to prepare, implement, and maintain a site-specific OIMP as described in Title 14 CCR 17863.4 and 17896.31, respectively. The OIMP shall describe the facility design and operation and be reviewed annually and revised, as necessary.

Question 6: Does the EA need to verify odor complaints in person with the complainant? What if a EA is unable to verify a complaint?

Answer 6: CalRecycle recommends that EAs confirm odors directly with a complainant’s participation, but it is not required. However, if the complainant is claiming that the odor is interfering with their use and comfortable enjoyment of life or property, their statement (written or verbal), should be documented consistent with and as described in 14 CCR 18302 (d)(3)(B). While verifying the odor complaint, the EA should observe at or near the complainant’s location. The EA should make every attempt to verify a complaint. However, if the EA cannot verify the compliant, the EA should document and file the attempts in the investigation record.

Question 7: To whom should the EA refer odor complaints regarding agricultural activities?

Answer 7: EAs must investigate complaints regarding a compostable material handling activity. In addition, 14 CCR, Article 8 – Agricultural Solid Waste Management Standards, beginning with section 17801 et seq, provide the EA with authority to investigate agricultural operations relative to excessive vectors, odor, dust, or feathers.
The EA should refer all other odor complaints to the air districts.

Question 8: If an operation is not required to have an OIMP, is it required to comply with Title 14 state minimum standards?

Answer 8: Yes.

Question 9: Can EA’s use air district findings to “verify” odor complaints?

Answer 9: An EA can use the air district staff inspector findings to assist them in their own investigation of odor complaints. However, the EA cannot rely entirely on air district findings to support their own determination of the validity of a complaint.

Question 10: Does the EA tell the operator what to include in their OIMP?

Answer 10: No, it is the responsibility of the operator to submit an OIMP that is consistent with the requirements in 14 CCR 17863.4 (for composting) or 17896.31 (for in-vessel digestion).

Question 11: When is an Odor Best Management Practices Feasibility Report needed?

Answer 11: An operators can voluntarily develop an Odor Best Management Practice Feasibility Report at any time, and EA may require a report after consecutive or chronic odor violations pursuant to Title 14 Section 17863.4(f) (for composting) or 17869.31(f) (for in-vessel digestion).

Question 12: Does an OIMP violation require more than one complaint to the EA?

Answer 12: There is no threshold relative to complaints and findings of noncompliance with the requirements to implement an OIMP. At any time that an EA finds that an OIMP is not effective in minimizing odors, they can cite the operator and require a corresponding revision to the OIMP. The EA finding that the OIMP is not effective is not dependent on verified odor complaints.

Question 13: Are EAs responsible for addressing odor issues associated with facilities and operations that handle compostable materials but do not meet the definition of a compostable material handling operation or facility or in-vessel facility?

Answer 13: EAs are only responsible for investigating odor complaints for Title 14 compostable material handling facilities and operations, such as composting, chippers and grinders, and in-vessel digesters

Question 14: Can other regulatory agencies, such as local air districts, have access to operating documents, such as an Odor Impact Minimization Plan (OIMP), for a specific compost facility? Can other regulatory agencies have access to best management practices used at compostable materials handling facilities and operations?

Answer 14: Yes, OIMPs are part of the operating record of compostable material handling activities and are available to the public.

Regulatory Tiers

Question 1: Pursuant to the exclusions in Title 14 California Code of Regulations (14 CCR) Section 17896.6(a)(2), digestate that is not composted may not be given away or sold. Is digestate that has been shown to meet pathogen reduction requirements, maximum metal concentration requirements, and physical contamination limits allowed to given away or sold?

Answer 1: In-vessel digested agricultural material that has been analyzed and shown to meet the requirements for metal concentration pursuant to 14 CCR 17896.59, pathogen density pursuant to 14 CCR 17896.60(b)(1), and physical contamination pursuant to 14 CCR 17896.61 can be considered compost produced from digestate and up to 1,000 cubic yards of such material may be given away or sold annually under the exemptions in 14 CCR 17896.6(a)(2).