Percolation Test Clauses: Contract for Real Property are clauses included in real estate contracts that require the land to pass a percolation test prior to closing. The purpose of these clauses is to ensure that the property has an adequate drainage and septic system. The percolation test, also known as the per test, is a professional engineering test that measures water percolation rate through the soil, which is needed to determine the suitability of a drain or septic system. There are two main types of Percolation Test Clauses: Contract for Real Property: 1. Seller-Provided Percolation Test Clause: This clause requires the seller to obtain a percolation test prior to closing and provide the results to the buyer. The clause also typically includes language regarding who pays for the test and the timeframe for the test to be completed. 2. Buyer-Requested Percolation Test Clause: This clause requires the buyer to request a percolation test prior to closing and pay for the test. The clause also typically includes language regarding when the test must be completed and the results must be provided to the seller.