Table of Contents

Exhibit31.1

CERTIFICATION PURSUANT TO SECTION 302 OFTHESARBANES-OXLEY ACT OF 2002

I, William H. Joyce,certify that:

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| 1.  | I have reviewed thisquarterly report on Form 10-Q of Nalco Holdings LLC; |

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| 2.  | Based on my knowledge, this report doesnot contain any untrue statement of material fact or omit to state amaterial fact necessary to make the statements made, in light of thecircumstance under which such statements were made, not misleading withrespect to the period covered by this report; |

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| 3.  | Based on my knowledge, the financialstatements, and other financial information included in this report,fairly represent in all material respects the financial condition,results of operations and cash flows of the registrant, as of, and for,the periods presented in this report; |

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| 4.  | The registrant’s othercertifying officer and I are responsible for establishing andmaintaining disclosure controls and procedures (as defined in ExchangeAct Rules 13a-15(e) and 15d-15(e)) and internal control over financialreporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f))for the registrant and have: |

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|  | (a)  | Designed such disclosure controlsand procedures, or caused such disclosure controls and procedures to bedesigned under our supervision, to ensure that material informationrelating to the registrant, including its consolidated subsidiaries, ismade known to us by others within those entities, particularly duringthe period in which this report is being prepared; |

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|  | (b)  | Designed such internal control overfinancial reporting, or caused such internal control over financialreporting to be designed under our supervision, to provide reasonableassurance regarding the reliability of financial reporting and thepreparation of financial statements for external purposes in accordancewith generally accepted accounting principles; |

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|  | (c)  | Evaluated the effectiveness of theregistrant’s disclosure controls and procedures and presented inthis report our conclusions about the effectiveness of the disclosurecontrols and procedures, as of the end of the period covered by thisreport based on such evaluation; and |

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|  | (d)  | Disclosed in this report any changein the registrant’s internal control over financial reportingthat occurred during the registrant’s most recent fiscal quarterthat has materially affected, or is reasonably likely to materiallyaffect, the registrant’s internal control over financialreporting; and |

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| 5.  | Theregistrant’s other certifying officer and I have disclosed,based on our most recent evaluation of internal control over financialreporting, to the registrant’s auditors and the audit committeeof the registrant’s board of directors (or persons performingthe equivalent functions): |

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|  | (a)  | Allsignificant deficiencies and material weaknesses in the design oroperation of internal control over financial reporting which arereasonably likely to adversely affect the registrant’s abilityto record, process, summarize and report financial information; and |

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|  | (b)  | Any fraud, whether or not material,that involves management or other employees who have a significant rolein the registrant’s internal control over financialreporting. |

Date: May  10,  2006

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| /s/ WILLIAM H. JOYCE                                                                                                       |  |   |
| Name:    William H.JoyceTitle:      Chairman and Chief Executive Officer |  |   |
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