INDIANA DEPARTMENT OF ENVIRONMENTAL MANAGEMENT

This nonrule policy document is intended solely as guidance and does not have the effect of law or represent formal Indiana Department of Environmental Management (IDEM) decisions or final actions. This nonrule policy document shall be used in conjunction with applicable laws. It does not replace applicable laws, and, if it conflicts with these laws, the laws shall control. This nonrule policy document may be put into effect by IDEM 30 days after presentation to the appropriate board. Pursuant to IC 13-14-1-11.5, this policy will be available for public inspection for at least 45 days prior to presentation to the appropriate board. If the nonrule policy is presented to more than one board, it will be effective 30 days after presentation to the last. IDEM will submit the policy to the Indiana Register for publication. Revisions to the policy will follow the same procedure of presentation to the board and publication.

Goals of the state regulated wetland program are to promote the net gain in higher quality isolated wetlands (IC 13-18-22-1(c)(1)) and to assure that compensatory mitigation will offset the loss of isolated wetlands allowed by the permitting program (IC 13-18-22-1(c)(2)). However, it is accepted that some wetland loss is unavoidable.

When applicants must impact a wetland, state law generally requires that they replace it with a compensatory mitigation wetland (IC 13-18-22-6). However, studies have found that compensatory wetland mitigation required by state and federal agencies often fails to fully compensate for the wetland loss authorized by the permit, even when compensatory mitigation wetlands are constructed per accepted scientific/engineering parameters.

In addition, a temporal loss of wetland function can occur because it takes many years from the time a wetland is constructed until it fully functions as a wetland or in the manner of the wetland it replaced. To overcome the risk of failure and the temporal loss of function, many state and federal agencies require the area of replacement wetland to be greater than the area of wetland lost. This is known as the mitigation ratio (for example, 2:1 means two acres of compensatory mitigation for each acre of wetland loss). IC 13-18-22-6 sets these ratios ranging from 1:1 to 3:1 for state regulated wetlands, depending on the class of the impacted wetland, whether the impacted wetland was forested or not, and if the replacement wetland is on-site or off-site relative to the permitted wetland loss. IC 13-18-22-6(b) provides an incentive to complete mitigation in advance of creating the impact to a wetland by lowering the required replacement/compensatory wetland mitigation to 1:1.

Since the passage of the isolated wetland statutes in 2004, many have questioned what IC 13-18-22-6(b) meant by "complete". One view has been that "complete" means when construction of the compensatory mitigation site has been finished. Another view has been that "complete" means when the mitigation site reaches a state equivalent to mature examples of the wetland ecosystem being replaced. IDEM has indicated that a wetland compensatory mitigation site is "complete" when it is demonstrated to successfully offset the loss of wetlands authorized by the permit. IDEM determined that the demonstration of "success" occurred through monitoring the site and comparing its performance against a set of success criteria included in an IDEM approved mitigation plan. Thus, IDEM has considered compensatory mitigation sites to be "complete" when the sites have met the success criteria for two consecutive years and a site was then released from additional monitoring.

Defining "complete" as "construction being finished" entails the risk of failure, as identified above. This is in conflict with the stated legislative goals. IDEM acknowledges that failure could still occur after the determination that the success criteria have been met for two consecutive years. However, accepting "complete" as achieving equivalency with examples of mature ecosystems of the type being replaced may require decades of monitoring by the applicant and oversight by IDEM. While this interpretation would pose the least risk of failure, resource constraints make it unworkable. Furthermore, reliance on a set of prespecified success criteria provides the property owner with certainty of a definite end to responsibility within a shorter time period.

Therefore, for the purposes of determining "complete" with respect to compensatory mitigation, "complete" is defined to mean that compensatory wetland mitigation site construction is finished and that the success criteria in the IDEM approved mitigation plan have been achieved for a period of two consecutive years.

The statutory goals of the state regulated wetland program support this definition over the competing interpretation of defining "complete" to mean simply "construction being finished," which would not assure that compensatory mitigation will offset the loss of isolated wetlands allowed by the permitting program.

DIN: 20061004-IR-318060431NRA

Composed: May 07,2024 11:06:04PM EDT

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