R&D tax credits might be the business relief that dominates accountants\u2019 time but in some ways it\u2019s not as generous as one of the most niche tax benefits going.\r\nRemediation of Contaminated Land (RoCL) tax relief has been around nearly as long as the R&D tax credit scheme \u2014 launched a year later in 2001 \u2014 and it makes up a tiny fraction of the overall number of claims received by HMRC each year.\r\nHowever, it has been specially designed to turn heads because ridding sites of pollution and bringing them back into use is central to the government\u2019s environmental and development strategy.\r\nThe main way the government has made RoCL more generous is by ensuring that 100% of subcontractor costs can be included in claims. This is in recognition of the fact that, unlike R&D, companies rarely have the expertise in-house to be able to do the work themselves.\r\nThis is because most firms will rarely need to consider decontaminating land and therefore have no need to maintain this expertise themselves.\r\nSo, under RoCL provisions, 100% of the qualifying costs borne by the subcontractor are claimable, which encourages companies to undertake this sort of work. In contrast, they are capped at 65% under the R&D tax credit scheme.\r\nThe RoCL is more generous in another way too. Qualifying losses can be surrendered for a tax credit at 16% under RoCL, whereas this falls to 14.5% for the R&D tax credit scheme.\r\nObviously, because claims are less common under RoCL, R&D tax credits will continue to be the biggest source of tax benefits. However, misunderstanding how much RoCL has to offer could influence whether an accountant thinks it is worth recommending a claim to a client at all.\r\nSome remediation works will be minor, while others involve the full range of qualifying costs needed to remove asbestos, Japanese Knotweed, heavy metals, fuel leaks and arsenic.\r\nThe relief was extended in 2009 to include derelict land and qualifying costs also include the removal of old structures, concrete bases and utilities.\r\n\r\nWhat qualifies?\r\nThe cost of materials (i.e. concrete barriers used to contain the contaminant in the ground) and labour both qualify.\r\nEven where staff at a claimant company are involved in RoCL, staff costs for their time are rarely claimed because labour is subject to an 80\/20 rule. This means that, if a staff member spends less than 20% of their time on RoCL, none of their costs can be claimed. Claimant company employees will almost never spend more than 20% of their time on RoCL.\r\nIn rare circumstances where they do, the entire cost of employing that person can be claimed if they spend more than 80% of their time on RoCL. Those staff who spend between 20% and 80% of their time on qualifying activities are claimed for the proportion of time they spent carrying them out.\r\nSpecialist subcontractor staff costs are, of course, claimable alongside professional advice, fencing and security costs incurred as a result of the work. The cost of preparatory work (as long as the remediation goes ahead) also qualifies \u2014 for example, surveys and excavations.\r\nIf any materials or contaminants have been sent to landfill, the landfill tax will not be claimable. Similarly, the hire of plant and machinery is not an allowable expense for relief.\r\nThis is a broad overview of the costs that can be claimed under RoCL, however, there are many more complex rules within the legislation so seek specialist advice if you are unsure in order to maximise a claim.\r\nRemember, land or buildings must be owned by a limited company at the time the remediation work is carried out and it must be owned either as a freehold or a leasehold of at least seven years.\r\nByline by Rachel Brett tax team manager at\u00a0Catax.