Exhibit 31.2CERTIFICATIONI, J. Paul Withrow, certify that:1. I have reviewed this quarterly report on Form 10-Q of Synagro Technologies, Inc.; 2. Based on my knowledge, this quarterly report does not contain any untrue statement of amaterial fact or omit to state a material fact necessary to make the statements made, in lightof the circumstances under which such statements were made, not misleading with respect to theperiod covered by this quarterly report; 3. Based on my knowledge, the financial statements, and other financial information included inthis quarterly report, fairly present in all material respects the financial condition,results of operations and cash flows of the registrant as of, and for, the periods presentedin this quarterly report; 4. The registrant’s other certifying officer(s) and I are responsible for establishing andmaintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and15d-15(e)) and internal control over financial reporting (as definedin Exchange Act Rule 13a-15(f) and 15(d)-15(f)) for the registrant and have: a. designed such disclosure controls and procedures, or caused such disclosure controls andprocedures to be designed under our supervision, to ensure that material informationrelating to the registrant, including its consolidated subsidiaries, is made known to us byothers within those entities, particularly during the period in which this quarterly reportis being prepared;  b. designed such internal control over financial reporting, or caused such internal controlover financial reporting to be designed under our supervision, to provide reasonableassurance regarding the reliability of financial reporting and the preparation of financialstatements for external purposes in accordance with generally accepted accountingprinciples; and  c. evaluated the effectiveness of the registrant’s disclosure controls and procedures andpresented in this quarterly report our conclusions about the effectiveness of the disclosurecontrols and procedures as of the end of the period covered by this report based on suchevaluation; and  d. disclosed in this quarterly report any changes in the registrant’s internal control overfinancial reporting that occurred during the registrant’s most recent fiscal quarter (theregistrant’s fourth fiscal quarter in the case of an annual report) that has materiallyaffected, or is reasonably likely to affect, the registrant’s internal control overfinancial reporting; and5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recentevaluation of internal controls over financial reporting, to the registrant’s auditors and theaudit committee of the registrant’s board of directors (or persons performing the equivalentfunction): a. all significant deficiencies and material weaknesses in the design or operation ofinternal controls over financial reporting, which are reasonably likely to adversely affectthe registrant’s ability to record, process, summarize and report financial information; and  b. any fraud, whether or not material, that involves management or other employees who havea significant role in the registrant’s internal controls over financial reporting.     Date: May 5, 2006 /s/ J. Paul Withrow         Chief Financial Officer and Director  
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