The budget for this project can be estimated based on the scope of work, which includes excavation, drainage, new soil delivery, compaction, leveling, old soil removal, and disposal for two softball fields. The cost of materials and labor for such a project can vary depending on the location, soil type, and equipment required. However, a rough estimate for a similar project in the United States could be around $50,000 to $200,000, considering the cost of materials, labor, and equipment. Since the project is located in Japan, the cost may be different due to variations in labor costs, material prices, and other factors. Therefore, a ballpark estimate for this project could be around ¥5,000,000 to ¥20,000,000 (approximately $45,000 to $180,000 USD), assuming an exchange rate of 1 USD = 110 JPY. The actual budget will depend on the contractor's quote and the government's evaluation of the proposal.