Source Trial Policy
This guidance document is advisory in nature but is binding on an agency until amended by such agency. A guidance document does not include internal procedural documents that only affect the internal operations of the agency and does not impose additional requirements or penalties on regulated parties or include confidential information or rules and regulations made in accordance with the Administrative Procedure Act. If you believe that this guidance document imposes additional requirements or penalties on regulated parties, you may request a review of the document.

Form #:  18-010
Guidance Documents
Revised: 3/5/20


The following policy is intended to clarify how the NDEE’s Air Quality Division (AQD) assesses a source request to conduct a trial to evaluate new process materials or methods or changes to controls. The AQD supports owner and operator interests in production and efficiency improvements in their processes, but it is the sources’ responsibility to be in continuous compliance with any applicable emission limitation or standard and determine whether any physical or operational changes made effects their compliance status. Trials may also be requested by a source when notification under the general conditions of a construction or operating permit is required for physical or operational changes made to an emissions unit or associated control equipment that may cause an increase in emissions. However, please note that if there is a reasonable expectation that a proposed trial will violate any applicable emission limitation, State or Federal regulation, then the trial cannot be accepted. If the proposed trial would violate an operational or control equipment limit, specific identification of the limit and AQD approval would need to be obtained before starting the trial. If data becomes available during the trial period that may indicate non- compliance with the permit or federal rule, the source trial should cease and notification by phone to the AQD should occur. Note, sources that have an operating permit will need to evaluate whether data that may indicate non-compliance is reportable as credible evidence in their deviation and certification of compliance reports.

The AQD recommends the following procedure when a source requests to conduct a trial without triggering a subsequent review by the AQD under Chapter 34. A source requesting a trial will submit to the AQD, at least 30 days before the start of the trial, a written request that provides a detailed description of the scope and objectives along with the proposed length of the trial. The request should detail if the trial is to be continuous or in stages, if test data is going to be obtained and at what point(s) in the trial. A schedule for conducting performance testing within the first 60 days during the trial must be included if the trial is scheduled to last longer than 30 days. If engineering emission data is obtained during the initial 30 day trial period, the AQD will consider whether to waive the performance testing requirement. The waiver will only be considered if the information is submitted by the 30th day of the trial.

Within 60 days following completion of the trial, the source must provide a report to the AQD detailing results of the objectives of the trial and whether the source intends to implement the trial change going forward or if returning back to the operating parameters prior to the trial. The report must also include any emissions and operational parameters data gathered during the trial. We encourage sources to contact the NDEE after completion of the trial, to determine if any modifications to construction or operating permits is necessary before implementing any permanent changes.

For any new trials being conducted within 12 months of a previous trial, compliance testing may be required during the trial regardless of trial length.

This trial policy does not apply to emission units using a certified CEM system for pollutants potentially affected by the trial. Other source or NDEE identified changes will be evaluated by NDEE under Title 129, Chapter 34 Section 001 to determine if prior testing would still be considered representative as well as whether additional performance testing is needed. Nothing in this policy waives the right of the AQD to require testing under Title 129, Chapter 34. This trial policy does not supersede or replace any regulatory requirement to apply for and obtain a permit.


Produced by: Nebraska Department of Environment and Energy, P.O. Box 98922, Lincoln, NE 68509-8922; phone (402) 471-2186. To view this, and other information related to our agency, visit our web site at http://dee.ne.gov.