Senate committee substitute makes the following changes to the 1st edition.

Amends the proposed definition of professionally supervised dam removal in GS 143-215.25 to define the term as the removal of a low- or intermediate-hazard dam that is not operated primarily for flood control or hydroelectric power generation purposes and is designed and supervised by a qualified engineer.

Amends the proposed new subsection (c) in GS 143-215.27, providing that a professionally supervised dam removal that complies with the specified requirements is not subject to the procedures set forth in subsection (a) of the statute. Modifies and adds to the specified requirements to include: (1) a qualified engineer must certify that the dam is a low- or intermediate-hazard dam; (2) the person proposing to remove the dam must notify the director of the Division of Energy, Mineral, and Land Resources of the Department of Environmental Quality (DEQ) of the proposed removal at least 60 days prior to removal (was, 30 days prior), and the notice must include the qualified engineer's name, NC license number, and notarized certification from the owner of the dam that the dam is a low- or intermediate-hazard dam not currently operated for the purposes of flood control or hydroelectric power generation; and (3) the person who proposes to remove the dam must notify the NC Floodplain Mapping Program of the Department of Public Safety, the NC Department of Transportation, adjacent property owners of the dam and reservoir, and all impacted local governments of the proposed removal at least 60 days prior to the removal (previously, did not include a time limitation for this notice, and did require notice be given to NC DOT or adjacent property owners), and the notice must also include a qualified engineer's determination that the removal will not increase impacts to downstream bridges or road crossings. Makes clarifying changes. 

Combines and modifies the proposed provisions in GS 143-215.28A to set the fee for notification of a professionally supervised dam removal under GS 143-215.27(c)(1) to be $500, to be paid to DEQ (was, not to exceed the lesser of 0.5% of the actual cost of removal or $500).

Eliminates the provisions recodifying and amending GS 143-215.32(a) and GS 143-215.32(a1) (pertaining to an owner's duty to inspect dams).

Makes clarifying change to the act's provisions directing the Environmental Management Commission to implement the Sediment Criteria Rule, measuring the height of a dam for purposes of dam size classification from the lowest point on the crest of the dam to the lowest point on the downstream toe, for implementing professionally supervised dam removals. 

Deletes the proposed new subdivision in GS 143B-135.234(c), which allowed funds to be appropriated from the Clean Water Management Trust Fund for the purposes of removing obsolete and unwanted dams where removal would enhance or restore ecological functions or improve water quality. 

Modifies the study of the dam removal process in the state to be conducted by DEQ to require the Department of Public Safety to jointly conduct the study with DEQ. Postpones the date the joint report must be submitted to the Environmental Commission to March 1, 2020 (was, March 1, 2018).