The Commission may allow a developer to design and construct any on–site or off–site facility necessary for the developer’s project if the facility is: in the Commission Capital Improvement Program and the 10–year Comprehensive Water Supply and Sewerage System Plan adopted by one of the county councils; a major project included in the Commission Capital Improvement Program; or a project that includes a sewer main or water main that: provides only local service; is 2,000 feet or less; has a diameter of: 15 inches or more if it is a sewer main; or 16 inches or more if it is a water main; and is built to avoid unnecessary and uneconomical duplication when a major project is constructed. A facility constructed under this section shall be designed, constructed, and inspected in accordance with: the standards used by the Commission; and all applicable laws, regulations, and written policies of the Commission. After the Commission approves a facility constructed by a developer under this section, the Commission shall: accept the facility as part of the Commission system; and subject to subsection (d) of this section, grant the developer a credit against any charge imposed under this subtitle in an amount equal to the cost of constructing the facility. The Office of the Inspector General shall review and approve the costs incurred by the developer. The Commission and the developer shall enter into an agreement that incorporates the provisions of this section. If the Commission rejects a developer’s request to design and construct facilities under this section, the Commission shall explain in writing to the developer the reasons for the rejection. The Commission shall submit a report at the end of each fiscal year to the Montgomery County and Prince George’s County Delegations to the General Assembly and to the county councils of Montgomery County and Prince George’s County. The report shall state the number of requests made by developers under this section, including: the number of acceptances and rejections by the Commission; and the justification for any rejections.