Section 53.14 - Modification of a reference or equivalent method(a) An applicant who offers a method for sale as a reference or equivalent method shall report to the EPA Administrator prior to implementation any intended modification of the method, including but not limited to modifications of design or construction or of operational and maintenance procedures specified in the operation manual (see § 53.9(g) ). The report shall be signed by an authorized representative of the applicant, marked in accordance with § 53.15 (if applicable), and addressed as specified in § 53.4(a) .(b) A report submitted under paragraph (a) of this section shall include:(1) A description, in such detail as may be appropriate, of the intended modification.(2) A brief statement of the applicant's belief that the modification will, will not, or may affect the performance characteristics of the method.(3) A brief statement of the probable effect if the applicant believes the modification will or may affect the performance characteristics of the method.(4) Such further information, including test data, as may be necessary to explain and support any statement required by paragraphs (b)(2) and (b)(3) of this section.(c) Within 90 calendar days after receiving a report under paragraph (a) of this section, the Administrator will take one or more of the following actions: (1) Notify the applicant that the designation will continue to apply to the method if the modification is implemented.(2) Send notice to the applicant that a new designation will apply to the method (as modified) if the modification is implemented, submit notice of the determination for publication in the FEDERAL REGISTER, and revise or supplement the list referred to in § 53.8(c) to reflect the determination.(3) Send notice to the applicant that the designation will not apply to the method (as modified) if the modification is implemented and submit notice of the determination for publication in the FEDERAL REGISTER.(4) Send notice to the applicant that additional information must be submitted before a determination can be made and specify the additional information that is needed (in such cases, the 90-day period shall commence upon receipt of the additional information).(5) Send notice to the applicant that additional tests are necessary and specify which tests are necessary and how they shall be interpreted (in such cases, the 90-day period shall commence upon receipt of the additional test data).(6) Send notice to the applicant that additional tests will be conducted by the Administrator and specify the reasons for and the nature of the additional tests (in such cases, the 90-day period shall commence 1 calendar day after the additional tests are completed).(d) An applicant who has received a notice under paragraph (c)(3) of this section may appeal the Administrator's action as follows: (1) The applicant may submit new or additional information pertinent to the intended modification.(2) The applicant may request the Administrator to reconsider data and information already submitted.(3) The applicant may request that the Administrator repeat any test conducted that was a material factor in the Administrator's determination. A representative of the applicant may be present during the performance of any such retest.62 FR 38784, July 18, 1997, as amended at 80 FR 65460 , Oct. 26, 2015