在所有符合生者者責任制度延伸的回收政策裡，押退保證金制度被公認為是一個有效率的制度。然而，在實際應用中，由於繳費的生產者與收費的回收業者對象不一致，此制度常面臨預算短缺的現象。本研究旨在探討一個專款專用的押退保證金回收制度，目的在檢驗此政策在哪些狀況之下較易產生預算短缺的問題。本研究發現，當回收成本相對高、環境邊際損害溫和以及產品市場越趨近於完全競爭時，專款專用的押退保證金制度的資源配置接近社會最適。這意味著在相反的情況之下，此回收政策較容易產生預算短缺的現象，亦即當回收成本相對較低、環境邊際損害大以及產品市場為不完全競爭時，實施專款專用押退保證金制度的社會福利會低於社會最適。

Amongst the recycling policies that carry the property of extended producer responsibilities, deposit-refund (D-R) is recognized an ideal policy as it can achieve a socially optimal outcome. In reality however, D-R often runs into a budget deficit. To correct for this void, we take the budget balance constraint into account in this paper, and re-examine the features of an earmarked D-R in recycling and output markets. Specifically, we investigate the circumstances under which a D-R runs into a budget deficit and examine the highest social welfare that an earmarked D-R can achieve. It is found that when recycling cost is relatively high, marginal environmental damage is mild, and the output market is competitive, the social welfare of an earmarked D-R is close to the social optimum. Under alternative conditions however, i.e., when recycling cost is low, marginal environmental damage is large, and output market is imperfect, it is more likely for a D-R to run into a financial deficit; this implies that the welfare of an earmarked D-R is less than the social optimum.