Credit trades may occur with or without the participation of an aggregator or broker. In the event of a default in a trade contract, expiration of a credit, or suspension or revocation of a credit, the buyer using the credit remains responsible for complying with any NPDES and State discharge permit or other regulatory requirement that the credit was intended to satisfy. Ratios Applicable to All Trades. Uncertainty Ratio. An uncertainty ratio of 1:1 shall be applied to trades involving credits generated by nonpoint sources and acquired by stormwater point sources or other nonregulated sources. An uncertainty ratio of 1:1 shall be applied to trades involving implementation of BMPs for land conservation that includes protection through an irrevocable conservation easement or other instrument attached to the property deed and recorded with the local circuit court. An uncertainty ratio of 2:1 shall be applied to trades involving credits generated by nonpoint sources and acquired by wastewater point sources, unless the generator, seller, or buyer of the credit is able to demonstrate to the Department that a lower ratio is justified and protective of water quality standards. Edge of Tide Ratio. An EoT numeric adjustment factor shall be applied to all applicable credits to normalize loads based on delivery to the mainstem of the Chesapeake Bay. The appropriate factor shall be calculated using assessment tools consistent with the Chesapeake Bay Program modeling tools and accepted by the Department. EoT adjustment factors for credits from wastewater point sources shall be determined by the Department based on the latest Chesapeake Bay Model used by the Department in issuing permits with trades. Reserve Ratio. A reserve ratio shall be applied to each credit when it is certified to create a reserve pool of credits that may be used by the Department to: Cover the loss of certified credits from a BMP damaged by events arising from sudden and reasonably unforeseeable events beyond the control of the person responsible for the maintenance of the BMP, including acts of God; Replace purchased credits that become unavailable due to the failure or underperformance of a BMP; Address a lack of readily available credits; or Improve the overall water quality during a year when the credits in the reserve pool are not used to support other purposes detailed in this chapter. Lifespan of Certified Credits. A BMP may only generate credits when it is installed and placed into operation and all operational and maintenance guidelines are followed. Credits may be certified for more than 1 year but shall be applied annually. The Department shall include the number of years a credit is generated as part of the credit certification. Local Water Quality. The use of a credit may not cause nor contribute to local water quality impairments or prevent the attainment of local water quality standards. Credits used within any impaired waters must be generated within such impaired waters or upstream of the credit user's discharge. Prohibitions. At its discretion, the Department may prohibit the following persons from generating credits: A permittee in noncompliance with permit terms; A nonregulated source or owner of an on-site sewage disposal system that is not in compliance with COMAR 26.04.03, 26.17.01, 26.17.02, 26.17.04, 26.23, or 26.24, if applicable; An agricultural operation that is not in compliance with COMAR 15.20.12; or A person who has previously violated any provision of the Environment Article or any regulation adopted under the Environment Article.